Al-Qurtas-Islamic-bank-The-.../src/base/ftstroke.c

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/***************************************************************************/
/* */
/* ftstroke.c */
/* */
/* FreeType path stroker (body). */
/* */
/* Copyright 2002-2006, 2008-2011, 2013, 2014 by */
/* David Turner, Robert Wilhelm, and Werner Lemberg. */
/* */
/* This file is part of the FreeType project, and may only be used, */
/* modified, and distributed under the terms of the FreeType project */
/* license, LICENSE.TXT. By continuing to use, modify, or distribute */
/* this file you indicate that you have read the license and */
/* understand and accept it fully. */
/* */
/***************************************************************************/
#include <ft2build.h>
#include FT_STROKER_H
#include FT_TRIGONOMETRY_H
#include FT_OUTLINE_H
#include FT_INTERNAL_MEMORY_H
#include FT_INTERNAL_DEBUG_H
#include FT_INTERNAL_OBJECTS_H
2004-12-14 00:16:59 +01:00
/* documentation is in ftstroke.h */
FT_EXPORT_DEF( FT_StrokerBorder )
FT_Outline_GetInsideBorder( FT_Outline* outline )
{
FT_Orientation o = FT_Outline_Get_Orientation( outline );
return o == FT_ORIENTATION_TRUETYPE ? FT_STROKER_BORDER_RIGHT
[ftstroke] Major revision. The main problems ----------------- o If FT_STROKER_LINEJOIN_BEVEL was specified, unlimited miter joins (not bevel joins) were generated. Indeed, the meanings of `miter' and `bevel' were incorrectly reversed (consistently) in both the code and comments. o The way bevel joins were constructed (whether specified explicitly, or created as a result of exceeding the miter limit) did not match what is required for stroked text in PostScript or PDF. The main fixes -------------- o The behaviour of FT_STROKER_LINEJOIN_BEVEL has been corrected. o A new line join style, FT_STROKER_LINEJOIN_MITER_FIXED, has been introduced to support PostScript and PDF miter joins. o FT_STROKER_LINEJOIN_MITER_VARIABLE has been introduced as an alias for FT_STROKER_LINEJOIN_MITER. Additionally, a variety of stroking errors have been fixed. These would cause various artifacts (including points `at infinity'), especially when stroking poor quality fonts. See http://lists.gnu.org/archive/html/freetype-devel/2011-07/msg00001.html for example documents. The FreeType stroker now produces results very similar to that produced by GhostScript and Distiller for these fonts. Other problems -------------- The following problems have been resolved: o Inside corners could be generated incorrectly. Intersecting the inside corner could cause a missing triangular area and other effects. The intersection point can only be used if the join is between two lines and both lines are long enough. The `optimization' condition in `ft_stroker_inside' has been corrected; this requires the line length to be passed into various functions and stored in `FT_StrokerRec'. o Incorrect cubic curves could be generated. The angle calculations in `FT_Stroker_CubicTo' have been corrected to handle the case of the curve crossing the +/-PI direction. o If the border radius was greater than the radius of curvature of a curve, then the negative sector would end up outside (not inside) the border. This situation is now recognized and the negative sector is circumnavigated in the opposite direction. (If round line joins are being used, this code is disabled because the line join will always cover the negative sector.) o When a curve is split, the arcs may not join smoothly (especially if the curve turns sharply back on itself). Changes in direction between adjacent arcs were not handled. A round corner is now added if the deviation from one arc to the next is greater than a suitable threshold. o The current direction wasn't retained if a the outline contained a zero length lineto or a curve that was determined to be `basically a point'. This could cause a spurious join to be added. o Cubics with close control points could be mishandled. All eight cases are now distinguished correctly. Other improvements ------------------ o Borders for cubic curves could be too `flat'. FT_SMALL_CUBIC_THRESHOLD has been reduced a little to prevent this. o The handling and use of movable points has been simplified a little. o Various values are now computed only if the results are actually needed. o The directions of the outer and inner borders have been swapped, as recommended by Graham Asher. * src/base/ftstroke.c: Revised. * include/freetype/ftstroke.h: Updated.
2011-07-02 12:09:52 +02:00
: FT_STROKER_BORDER_LEFT;
}
2004-12-14 00:16:59 +01:00
/* documentation is in ftstroke.h */
FT_EXPORT_DEF( FT_StrokerBorder )
FT_Outline_GetOutsideBorder( FT_Outline* outline )
{
FT_Orientation o = FT_Outline_Get_Orientation( outline );
return o == FT_ORIENTATION_TRUETYPE ? FT_STROKER_BORDER_LEFT
[ftstroke] Major revision. The main problems ----------------- o If FT_STROKER_LINEJOIN_BEVEL was specified, unlimited miter joins (not bevel joins) were generated. Indeed, the meanings of `miter' and `bevel' were incorrectly reversed (consistently) in both the code and comments. o The way bevel joins were constructed (whether specified explicitly, or created as a result of exceeding the miter limit) did not match what is required for stroked text in PostScript or PDF. The main fixes -------------- o The behaviour of FT_STROKER_LINEJOIN_BEVEL has been corrected. o A new line join style, FT_STROKER_LINEJOIN_MITER_FIXED, has been introduced to support PostScript and PDF miter joins. o FT_STROKER_LINEJOIN_MITER_VARIABLE has been introduced as an alias for FT_STROKER_LINEJOIN_MITER. Additionally, a variety of stroking errors have been fixed. These would cause various artifacts (including points `at infinity'), especially when stroking poor quality fonts. See http://lists.gnu.org/archive/html/freetype-devel/2011-07/msg00001.html for example documents. The FreeType stroker now produces results very similar to that produced by GhostScript and Distiller for these fonts. Other problems -------------- The following problems have been resolved: o Inside corners could be generated incorrectly. Intersecting the inside corner could cause a missing triangular area and other effects. The intersection point can only be used if the join is between two lines and both lines are long enough. The `optimization' condition in `ft_stroker_inside' has been corrected; this requires the line length to be passed into various functions and stored in `FT_StrokerRec'. o Incorrect cubic curves could be generated. The angle calculations in `FT_Stroker_CubicTo' have been corrected to handle the case of the curve crossing the +/-PI direction. o If the border radius was greater than the radius of curvature of a curve, then the negative sector would end up outside (not inside) the border. This situation is now recognized and the negative sector is circumnavigated in the opposite direction. (If round line joins are being used, this code is disabled because the line join will always cover the negative sector.) o When a curve is split, the arcs may not join smoothly (especially if the curve turns sharply back on itself). Changes in direction between adjacent arcs were not handled. A round corner is now added if the deviation from one arc to the next is greater than a suitable threshold. o The current direction wasn't retained if a the outline contained a zero length lineto or a curve that was determined to be `basically a point'. This could cause a spurious join to be added. o Cubics with close control points could be mishandled. All eight cases are now distinguished correctly. Other improvements ------------------ o Borders for cubic curves could be too `flat'. FT_SMALL_CUBIC_THRESHOLD has been reduced a little to prevent this. o The handling and use of movable points has been simplified a little. o Various values are now computed only if the results are actually needed. o The directions of the outer and inner borders have been swapped, as recommended by Graham Asher. * src/base/ftstroke.c: Revised. * include/freetype/ftstroke.h: Updated.
2011-07-02 12:09:52 +02:00
: FT_STROKER_BORDER_RIGHT;
}
[ftstroke] Major revision. The main problems ----------------- o If FT_STROKER_LINEJOIN_BEVEL was specified, unlimited miter joins (not bevel joins) were generated. Indeed, the meanings of `miter' and `bevel' were incorrectly reversed (consistently) in both the code and comments. o The way bevel joins were constructed (whether specified explicitly, or created as a result of exceeding the miter limit) did not match what is required for stroked text in PostScript or PDF. The main fixes -------------- o The behaviour of FT_STROKER_LINEJOIN_BEVEL has been corrected. o A new line join style, FT_STROKER_LINEJOIN_MITER_FIXED, has been introduced to support PostScript and PDF miter joins. o FT_STROKER_LINEJOIN_MITER_VARIABLE has been introduced as an alias for FT_STROKER_LINEJOIN_MITER. Additionally, a variety of stroking errors have been fixed. These would cause various artifacts (including points `at infinity'), especially when stroking poor quality fonts. See http://lists.gnu.org/archive/html/freetype-devel/2011-07/msg00001.html for example documents. The FreeType stroker now produces results very similar to that produced by GhostScript and Distiller for these fonts. Other problems -------------- The following problems have been resolved: o Inside corners could be generated incorrectly. Intersecting the inside corner could cause a missing triangular area and other effects. The intersection point can only be used if the join is between two lines and both lines are long enough. The `optimization' condition in `ft_stroker_inside' has been corrected; this requires the line length to be passed into various functions and stored in `FT_StrokerRec'. o Incorrect cubic curves could be generated. The angle calculations in `FT_Stroker_CubicTo' have been corrected to handle the case of the curve crossing the +/-PI direction. o If the border radius was greater than the radius of curvature of a curve, then the negative sector would end up outside (not inside) the border. This situation is now recognized and the negative sector is circumnavigated in the opposite direction. (If round line joins are being used, this code is disabled because the line join will always cover the negative sector.) o When a curve is split, the arcs may not join smoothly (especially if the curve turns sharply back on itself). Changes in direction between adjacent arcs were not handled. A round corner is now added if the deviation from one arc to the next is greater than a suitable threshold. o The current direction wasn't retained if a the outline contained a zero length lineto or a curve that was determined to be `basically a point'. This could cause a spurious join to be added. o Cubics with close control points could be mishandled. All eight cases are now distinguished correctly. Other improvements ------------------ o Borders for cubic curves could be too `flat'. FT_SMALL_CUBIC_THRESHOLD has been reduced a little to prevent this. o The handling and use of movable points has been simplified a little. o Various values are now computed only if the results are actually needed. o The directions of the outer and inner borders have been swapped, as recommended by Graham Asher. * src/base/ftstroke.c: Revised. * include/freetype/ftstroke.h: Updated.
2011-07-02 12:09:52 +02:00
/*************************************************************************/
/*************************************************************************/
/***** *****/
/***** BEZIER COMPUTATIONS *****/
/***** *****/
/*************************************************************************/
/*************************************************************************/
#define FT_SMALL_CONIC_THRESHOLD ( FT_ANGLE_PI / 6 )
[ftstroke] Major revision. The main problems ----------------- o If FT_STROKER_LINEJOIN_BEVEL was specified, unlimited miter joins (not bevel joins) were generated. Indeed, the meanings of `miter' and `bevel' were incorrectly reversed (consistently) in both the code and comments. o The way bevel joins were constructed (whether specified explicitly, or created as a result of exceeding the miter limit) did not match what is required for stroked text in PostScript or PDF. The main fixes -------------- o The behaviour of FT_STROKER_LINEJOIN_BEVEL has been corrected. o A new line join style, FT_STROKER_LINEJOIN_MITER_FIXED, has been introduced to support PostScript and PDF miter joins. o FT_STROKER_LINEJOIN_MITER_VARIABLE has been introduced as an alias for FT_STROKER_LINEJOIN_MITER. Additionally, a variety of stroking errors have been fixed. These would cause various artifacts (including points `at infinity'), especially when stroking poor quality fonts. See http://lists.gnu.org/archive/html/freetype-devel/2011-07/msg00001.html for example documents. The FreeType stroker now produces results very similar to that produced by GhostScript and Distiller for these fonts. Other problems -------------- The following problems have been resolved: o Inside corners could be generated incorrectly. Intersecting the inside corner could cause a missing triangular area and other effects. The intersection point can only be used if the join is between two lines and both lines are long enough. The `optimization' condition in `ft_stroker_inside' has been corrected; this requires the line length to be passed into various functions and stored in `FT_StrokerRec'. o Incorrect cubic curves could be generated. The angle calculations in `FT_Stroker_CubicTo' have been corrected to handle the case of the curve crossing the +/-PI direction. o If the border radius was greater than the radius of curvature of a curve, then the negative sector would end up outside (not inside) the border. This situation is now recognized and the negative sector is circumnavigated in the opposite direction. (If round line joins are being used, this code is disabled because the line join will always cover the negative sector.) o When a curve is split, the arcs may not join smoothly (especially if the curve turns sharply back on itself). Changes in direction between adjacent arcs were not handled. A round corner is now added if the deviation from one arc to the next is greater than a suitable threshold. o The current direction wasn't retained if a the outline contained a zero length lineto or a curve that was determined to be `basically a point'. This could cause a spurious join to be added. o Cubics with close control points could be mishandled. All eight cases are now distinguished correctly. Other improvements ------------------ o Borders for cubic curves could be too `flat'. FT_SMALL_CUBIC_THRESHOLD has been reduced a little to prevent this. o The handling and use of movable points has been simplified a little. o Various values are now computed only if the results are actually needed. o The directions of the outer and inner borders have been swapped, as recommended by Graham Asher. * src/base/ftstroke.c: Revised. * include/freetype/ftstroke.h: Updated.
2011-07-02 12:09:52 +02:00
#define FT_SMALL_CUBIC_THRESHOLD ( FT_ANGLE_PI / 8 )
#define FT_EPSILON 2
#define FT_IS_SMALL( x ) ( (x) > -FT_EPSILON && (x) < FT_EPSILON )
static FT_Pos
ft_pos_abs( FT_Pos x )
{
[ftstroke] Major revision. The main problems ----------------- o If FT_STROKER_LINEJOIN_BEVEL was specified, unlimited miter joins (not bevel joins) were generated. Indeed, the meanings of `miter' and `bevel' were incorrectly reversed (consistently) in both the code and comments. o The way bevel joins were constructed (whether specified explicitly, or created as a result of exceeding the miter limit) did not match what is required for stroked text in PostScript or PDF. The main fixes -------------- o The behaviour of FT_STROKER_LINEJOIN_BEVEL has been corrected. o A new line join style, FT_STROKER_LINEJOIN_MITER_FIXED, has been introduced to support PostScript and PDF miter joins. o FT_STROKER_LINEJOIN_MITER_VARIABLE has been introduced as an alias for FT_STROKER_LINEJOIN_MITER. Additionally, a variety of stroking errors have been fixed. These would cause various artifacts (including points `at infinity'), especially when stroking poor quality fonts. See http://lists.gnu.org/archive/html/freetype-devel/2011-07/msg00001.html for example documents. The FreeType stroker now produces results very similar to that produced by GhostScript and Distiller for these fonts. Other problems -------------- The following problems have been resolved: o Inside corners could be generated incorrectly. Intersecting the inside corner could cause a missing triangular area and other effects. The intersection point can only be used if the join is between two lines and both lines are long enough. The `optimization' condition in `ft_stroker_inside' has been corrected; this requires the line length to be passed into various functions and stored in `FT_StrokerRec'. o Incorrect cubic curves could be generated. The angle calculations in `FT_Stroker_CubicTo' have been corrected to handle the case of the curve crossing the +/-PI direction. o If the border radius was greater than the radius of curvature of a curve, then the negative sector would end up outside (not inside) the border. This situation is now recognized and the negative sector is circumnavigated in the opposite direction. (If round line joins are being used, this code is disabled because the line join will always cover the negative sector.) o When a curve is split, the arcs may not join smoothly (especially if the curve turns sharply back on itself). Changes in direction between adjacent arcs were not handled. A round corner is now added if the deviation from one arc to the next is greater than a suitable threshold. o The current direction wasn't retained if a the outline contained a zero length lineto or a curve that was determined to be `basically a point'. This could cause a spurious join to be added. o Cubics with close control points could be mishandled. All eight cases are now distinguished correctly. Other improvements ------------------ o Borders for cubic curves could be too `flat'. FT_SMALL_CUBIC_THRESHOLD has been reduced a little to prevent this. o The handling and use of movable points has been simplified a little. o Various values are now computed only if the results are actually needed. o The directions of the outer and inner borders have been swapped, as recommended by Graham Asher. * src/base/ftstroke.c: Revised. * include/freetype/ftstroke.h: Updated.
2011-07-02 12:09:52 +02:00
return x >= 0 ? x : -x;
}
static void
ft_conic_split( FT_Vector* base )
{
FT_Pos a, b;
base[4].x = base[2].x;
b = base[1].x;
a = base[3].x = ( base[2].x + b ) / 2;
b = base[1].x = ( base[0].x + b ) / 2;
base[2].x = ( a + b ) / 2;
base[4].y = base[2].y;
b = base[1].y;
a = base[3].y = ( base[2].y + b ) / 2;
b = base[1].y = ( base[0].y + b ) / 2;
base[2].y = ( a + b ) / 2;
}
static FT_Bool
ft_conic_is_small_enough( FT_Vector* base,
FT_Angle *angle_in,
FT_Angle *angle_out )
{
FT_Vector d1, d2;
FT_Angle theta;
FT_Int close1, close2;
d1.x = base[1].x - base[2].x;
d1.y = base[1].y - base[2].y;
d2.x = base[0].x - base[1].x;
d2.y = base[0].y - base[1].y;
close1 = FT_IS_SMALL( d1.x ) && FT_IS_SMALL( d1.y );
close2 = FT_IS_SMALL( d2.x ) && FT_IS_SMALL( d2.y );
if ( close1 )
{
if ( close2 )
[ftstroke] Major revision. The main problems ----------------- o If FT_STROKER_LINEJOIN_BEVEL was specified, unlimited miter joins (not bevel joins) were generated. Indeed, the meanings of `miter' and `bevel' were incorrectly reversed (consistently) in both the code and comments. o The way bevel joins were constructed (whether specified explicitly, or created as a result of exceeding the miter limit) did not match what is required for stroked text in PostScript or PDF. The main fixes -------------- o The behaviour of FT_STROKER_LINEJOIN_BEVEL has been corrected. o A new line join style, FT_STROKER_LINEJOIN_MITER_FIXED, has been introduced to support PostScript and PDF miter joins. o FT_STROKER_LINEJOIN_MITER_VARIABLE has been introduced as an alias for FT_STROKER_LINEJOIN_MITER. Additionally, a variety of stroking errors have been fixed. These would cause various artifacts (including points `at infinity'), especially when stroking poor quality fonts. See http://lists.gnu.org/archive/html/freetype-devel/2011-07/msg00001.html for example documents. The FreeType stroker now produces results very similar to that produced by GhostScript and Distiller for these fonts. Other problems -------------- The following problems have been resolved: o Inside corners could be generated incorrectly. Intersecting the inside corner could cause a missing triangular area and other effects. The intersection point can only be used if the join is between two lines and both lines are long enough. The `optimization' condition in `ft_stroker_inside' has been corrected; this requires the line length to be passed into various functions and stored in `FT_StrokerRec'. o Incorrect cubic curves could be generated. The angle calculations in `FT_Stroker_CubicTo' have been corrected to handle the case of the curve crossing the +/-PI direction. o If the border radius was greater than the radius of curvature of a curve, then the negative sector would end up outside (not inside) the border. This situation is now recognized and the negative sector is circumnavigated in the opposite direction. (If round line joins are being used, this code is disabled because the line join will always cover the negative sector.) o When a curve is split, the arcs may not join smoothly (especially if the curve turns sharply back on itself). Changes in direction between adjacent arcs were not handled. A round corner is now added if the deviation from one arc to the next is greater than a suitable threshold. o The current direction wasn't retained if a the outline contained a zero length lineto or a curve that was determined to be `basically a point'. This could cause a spurious join to be added. o Cubics with close control points could be mishandled. All eight cases are now distinguished correctly. Other improvements ------------------ o Borders for cubic curves could be too `flat'. FT_SMALL_CUBIC_THRESHOLD has been reduced a little to prevent this. o The handling and use of movable points has been simplified a little. o Various values are now computed only if the results are actually needed. o The directions of the outer and inner borders have been swapped, as recommended by Graham Asher. * src/base/ftstroke.c: Revised. * include/freetype/ftstroke.h: Updated.
2011-07-02 12:09:52 +02:00
{
/* basically a point; */
/* do nothing to retain original direction */
}
else
[ftstroke] Major revision. The main problems ----------------- o If FT_STROKER_LINEJOIN_BEVEL was specified, unlimited miter joins (not bevel joins) were generated. Indeed, the meanings of `miter' and `bevel' were incorrectly reversed (consistently) in both the code and comments. o The way bevel joins were constructed (whether specified explicitly, or created as a result of exceeding the miter limit) did not match what is required for stroked text in PostScript or PDF. The main fixes -------------- o The behaviour of FT_STROKER_LINEJOIN_BEVEL has been corrected. o A new line join style, FT_STROKER_LINEJOIN_MITER_FIXED, has been introduced to support PostScript and PDF miter joins. o FT_STROKER_LINEJOIN_MITER_VARIABLE has been introduced as an alias for FT_STROKER_LINEJOIN_MITER. Additionally, a variety of stroking errors have been fixed. These would cause various artifacts (including points `at infinity'), especially when stroking poor quality fonts. See http://lists.gnu.org/archive/html/freetype-devel/2011-07/msg00001.html for example documents. The FreeType stroker now produces results very similar to that produced by GhostScript and Distiller for these fonts. Other problems -------------- The following problems have been resolved: o Inside corners could be generated incorrectly. Intersecting the inside corner could cause a missing triangular area and other effects. The intersection point can only be used if the join is between two lines and both lines are long enough. The `optimization' condition in `ft_stroker_inside' has been corrected; this requires the line length to be passed into various functions and stored in `FT_StrokerRec'. o Incorrect cubic curves could be generated. The angle calculations in `FT_Stroker_CubicTo' have been corrected to handle the case of the curve crossing the +/-PI direction. o If the border radius was greater than the radius of curvature of a curve, then the negative sector would end up outside (not inside) the border. This situation is now recognized and the negative sector is circumnavigated in the opposite direction. (If round line joins are being used, this code is disabled because the line join will always cover the negative sector.) o When a curve is split, the arcs may not join smoothly (especially if the curve turns sharply back on itself). Changes in direction between adjacent arcs were not handled. A round corner is now added if the deviation from one arc to the next is greater than a suitable threshold. o The current direction wasn't retained if a the outline contained a zero length lineto or a curve that was determined to be `basically a point'. This could cause a spurious join to be added. o Cubics with close control points could be mishandled. All eight cases are now distinguished correctly. Other improvements ------------------ o Borders for cubic curves could be too `flat'. FT_SMALL_CUBIC_THRESHOLD has been reduced a little to prevent this. o The handling and use of movable points has been simplified a little. o Various values are now computed only if the results are actually needed. o The directions of the outer and inner borders have been swapped, as recommended by Graham Asher. * src/base/ftstroke.c: Revised. * include/freetype/ftstroke.h: Updated.
2011-07-02 12:09:52 +02:00
{
*angle_in =
*angle_out = FT_Atan2( d2.x, d2.y );
}
}
[ftstroke] Major revision. The main problems ----------------- o If FT_STROKER_LINEJOIN_BEVEL was specified, unlimited miter joins (not bevel joins) were generated. Indeed, the meanings of `miter' and `bevel' were incorrectly reversed (consistently) in both the code and comments. o The way bevel joins were constructed (whether specified explicitly, or created as a result of exceeding the miter limit) did not match what is required for stroked text in PostScript or PDF. The main fixes -------------- o The behaviour of FT_STROKER_LINEJOIN_BEVEL has been corrected. o A new line join style, FT_STROKER_LINEJOIN_MITER_FIXED, has been introduced to support PostScript and PDF miter joins. o FT_STROKER_LINEJOIN_MITER_VARIABLE has been introduced as an alias for FT_STROKER_LINEJOIN_MITER. Additionally, a variety of stroking errors have been fixed. These would cause various artifacts (including points `at infinity'), especially when stroking poor quality fonts. See http://lists.gnu.org/archive/html/freetype-devel/2011-07/msg00001.html for example documents. The FreeType stroker now produces results very similar to that produced by GhostScript and Distiller for these fonts. Other problems -------------- The following problems have been resolved: o Inside corners could be generated incorrectly. Intersecting the inside corner could cause a missing triangular area and other effects. The intersection point can only be used if the join is between two lines and both lines are long enough. The `optimization' condition in `ft_stroker_inside' has been corrected; this requires the line length to be passed into various functions and stored in `FT_StrokerRec'. o Incorrect cubic curves could be generated. The angle calculations in `FT_Stroker_CubicTo' have been corrected to handle the case of the curve crossing the +/-PI direction. o If the border radius was greater than the radius of curvature of a curve, then the negative sector would end up outside (not inside) the border. This situation is now recognized and the negative sector is circumnavigated in the opposite direction. (If round line joins are being used, this code is disabled because the line join will always cover the negative sector.) o When a curve is split, the arcs may not join smoothly (especially if the curve turns sharply back on itself). Changes in direction between adjacent arcs were not handled. A round corner is now added if the deviation from one arc to the next is greater than a suitable threshold. o The current direction wasn't retained if a the outline contained a zero length lineto or a curve that was determined to be `basically a point'. This could cause a spurious join to be added. o Cubics with close control points could be mishandled. All eight cases are now distinguished correctly. Other improvements ------------------ o Borders for cubic curves could be too `flat'. FT_SMALL_CUBIC_THRESHOLD has been reduced a little to prevent this. o The handling and use of movable points has been simplified a little. o Various values are now computed only if the results are actually needed. o The directions of the outer and inner borders have been swapped, as recommended by Graham Asher. * src/base/ftstroke.c: Revised. * include/freetype/ftstroke.h: Updated.
2011-07-02 12:09:52 +02:00
else /* !close1 */
{
[ftstroke] Major revision. The main problems ----------------- o If FT_STROKER_LINEJOIN_BEVEL was specified, unlimited miter joins (not bevel joins) were generated. Indeed, the meanings of `miter' and `bevel' were incorrectly reversed (consistently) in both the code and comments. o The way bevel joins were constructed (whether specified explicitly, or created as a result of exceeding the miter limit) did not match what is required for stroked text in PostScript or PDF. The main fixes -------------- o The behaviour of FT_STROKER_LINEJOIN_BEVEL has been corrected. o A new line join style, FT_STROKER_LINEJOIN_MITER_FIXED, has been introduced to support PostScript and PDF miter joins. o FT_STROKER_LINEJOIN_MITER_VARIABLE has been introduced as an alias for FT_STROKER_LINEJOIN_MITER. Additionally, a variety of stroking errors have been fixed. These would cause various artifacts (including points `at infinity'), especially when stroking poor quality fonts. See http://lists.gnu.org/archive/html/freetype-devel/2011-07/msg00001.html for example documents. The FreeType stroker now produces results very similar to that produced by GhostScript and Distiller for these fonts. Other problems -------------- The following problems have been resolved: o Inside corners could be generated incorrectly. Intersecting the inside corner could cause a missing triangular area and other effects. The intersection point can only be used if the join is between two lines and both lines are long enough. The `optimization' condition in `ft_stroker_inside' has been corrected; this requires the line length to be passed into various functions and stored in `FT_StrokerRec'. o Incorrect cubic curves could be generated. The angle calculations in `FT_Stroker_CubicTo' have been corrected to handle the case of the curve crossing the +/-PI direction. o If the border radius was greater than the radius of curvature of a curve, then the negative sector would end up outside (not inside) the border. This situation is now recognized and the negative sector is circumnavigated in the opposite direction. (If round line joins are being used, this code is disabled because the line join will always cover the negative sector.) o When a curve is split, the arcs may not join smoothly (especially if the curve turns sharply back on itself). Changes in direction between adjacent arcs were not handled. A round corner is now added if the deviation from one arc to the next is greater than a suitable threshold. o The current direction wasn't retained if a the outline contained a zero length lineto or a curve that was determined to be `basically a point'. This could cause a spurious join to be added. o Cubics with close control points could be mishandled. All eight cases are now distinguished correctly. Other improvements ------------------ o Borders for cubic curves could be too `flat'. FT_SMALL_CUBIC_THRESHOLD has been reduced a little to prevent this. o The handling and use of movable points has been simplified a little. o Various values are now computed only if the results are actually needed. o The directions of the outer and inner borders have been swapped, as recommended by Graham Asher. * src/base/ftstroke.c: Revised. * include/freetype/ftstroke.h: Updated.
2011-07-02 12:09:52 +02:00
if ( close2 )
{
*angle_in =
*angle_out = FT_Atan2( d1.x, d1.y );
}
else
{
*angle_in = FT_Atan2( d1.x, d1.y );
*angle_out = FT_Atan2( d2.x, d2.y );
}
}
theta = ft_pos_abs( FT_Angle_Diff( *angle_in, *angle_out ) );
return FT_BOOL( theta < FT_SMALL_CONIC_THRESHOLD );
}
static void
ft_cubic_split( FT_Vector* base )
{
FT_Pos a, b, c, d;
base[6].x = base[3].x;
c = base[1].x;
d = base[2].x;
base[1].x = a = ( base[0].x + c ) / 2;
base[5].x = b = ( base[3].x + d ) / 2;
c = ( c + d ) / 2;
base[2].x = a = ( a + c ) / 2;
base[4].x = b = ( b + c ) / 2;
base[3].x = ( a + b ) / 2;
base[6].y = base[3].y;
c = base[1].y;
d = base[2].y;
base[1].y = a = ( base[0].y + c ) / 2;
base[5].y = b = ( base[3].y + d ) / 2;
c = ( c + d ) / 2;
base[2].y = a = ( a + c ) / 2;
base[4].y = b = ( b + c ) / 2;
base[3].y = ( a + b ) / 2;
}
[ftstroke] Major revision. The main problems ----------------- o If FT_STROKER_LINEJOIN_BEVEL was specified, unlimited miter joins (not bevel joins) were generated. Indeed, the meanings of `miter' and `bevel' were incorrectly reversed (consistently) in both the code and comments. o The way bevel joins were constructed (whether specified explicitly, or created as a result of exceeding the miter limit) did not match what is required for stroked text in PostScript or PDF. The main fixes -------------- o The behaviour of FT_STROKER_LINEJOIN_BEVEL has been corrected. o A new line join style, FT_STROKER_LINEJOIN_MITER_FIXED, has been introduced to support PostScript and PDF miter joins. o FT_STROKER_LINEJOIN_MITER_VARIABLE has been introduced as an alias for FT_STROKER_LINEJOIN_MITER. Additionally, a variety of stroking errors have been fixed. These would cause various artifacts (including points `at infinity'), especially when stroking poor quality fonts. See http://lists.gnu.org/archive/html/freetype-devel/2011-07/msg00001.html for example documents. The FreeType stroker now produces results very similar to that produced by GhostScript and Distiller for these fonts. Other problems -------------- The following problems have been resolved: o Inside corners could be generated incorrectly. Intersecting the inside corner could cause a missing triangular area and other effects. The intersection point can only be used if the join is between two lines and both lines are long enough. The `optimization' condition in `ft_stroker_inside' has been corrected; this requires the line length to be passed into various functions and stored in `FT_StrokerRec'. o Incorrect cubic curves could be generated. The angle calculations in `FT_Stroker_CubicTo' have been corrected to handle the case of the curve crossing the +/-PI direction. o If the border radius was greater than the radius of curvature of a curve, then the negative sector would end up outside (not inside) the border. This situation is now recognized and the negative sector is circumnavigated in the opposite direction. (If round line joins are being used, this code is disabled because the line join will always cover the negative sector.) o When a curve is split, the arcs may not join smoothly (especially if the curve turns sharply back on itself). Changes in direction between adjacent arcs were not handled. A round corner is now added if the deviation from one arc to the next is greater than a suitable threshold. o The current direction wasn't retained if a the outline contained a zero length lineto or a curve that was determined to be `basically a point'. This could cause a spurious join to be added. o Cubics with close control points could be mishandled. All eight cases are now distinguished correctly. Other improvements ------------------ o Borders for cubic curves could be too `flat'. FT_SMALL_CUBIC_THRESHOLD has been reduced a little to prevent this. o The handling and use of movable points has been simplified a little. o Various values are now computed only if the results are actually needed. o The directions of the outer and inner borders have been swapped, as recommended by Graham Asher. * src/base/ftstroke.c: Revised. * include/freetype/ftstroke.h: Updated.
2011-07-02 12:09:52 +02:00
/* Return the average of `angle1' and `angle2'. */
/* This gives correct result even if `angle1' and `angle2' */
/* have opposite signs. */
static FT_Angle
ft_angle_mean( FT_Angle angle1,
FT_Angle angle2 )
{
return angle1 + FT_Angle_Diff( angle1, angle2 ) / 2;
}
static FT_Bool
ft_cubic_is_small_enough( FT_Vector* base,
FT_Angle *angle_in,
FT_Angle *angle_mid,
FT_Angle *angle_out )
{
FT_Vector d1, d2, d3;
FT_Angle theta1, theta2;
FT_Int close1, close2, close3;
d1.x = base[2].x - base[3].x;
d1.y = base[2].y - base[3].y;
d2.x = base[1].x - base[2].x;
d2.y = base[1].y - base[2].y;
d3.x = base[0].x - base[1].x;
d3.y = base[0].y - base[1].y;
close1 = FT_IS_SMALL( d1.x ) && FT_IS_SMALL( d1.y );
close2 = FT_IS_SMALL( d2.x ) && FT_IS_SMALL( d2.y );
close3 = FT_IS_SMALL( d3.x ) && FT_IS_SMALL( d3.y );
[ftstroke] Major revision. The main problems ----------------- o If FT_STROKER_LINEJOIN_BEVEL was specified, unlimited miter joins (not bevel joins) were generated. Indeed, the meanings of `miter' and `bevel' were incorrectly reversed (consistently) in both the code and comments. o The way bevel joins were constructed (whether specified explicitly, or created as a result of exceeding the miter limit) did not match what is required for stroked text in PostScript or PDF. The main fixes -------------- o The behaviour of FT_STROKER_LINEJOIN_BEVEL has been corrected. o A new line join style, FT_STROKER_LINEJOIN_MITER_FIXED, has been introduced to support PostScript and PDF miter joins. o FT_STROKER_LINEJOIN_MITER_VARIABLE has been introduced as an alias for FT_STROKER_LINEJOIN_MITER. Additionally, a variety of stroking errors have been fixed. These would cause various artifacts (including points `at infinity'), especially when stroking poor quality fonts. See http://lists.gnu.org/archive/html/freetype-devel/2011-07/msg00001.html for example documents. The FreeType stroker now produces results very similar to that produced by GhostScript and Distiller for these fonts. Other problems -------------- The following problems have been resolved: o Inside corners could be generated incorrectly. Intersecting the inside corner could cause a missing triangular area and other effects. The intersection point can only be used if the join is between two lines and both lines are long enough. The `optimization' condition in `ft_stroker_inside' has been corrected; this requires the line length to be passed into various functions and stored in `FT_StrokerRec'. o Incorrect cubic curves could be generated. The angle calculations in `FT_Stroker_CubicTo' have been corrected to handle the case of the curve crossing the +/-PI direction. o If the border radius was greater than the radius of curvature of a curve, then the negative sector would end up outside (not inside) the border. This situation is now recognized and the negative sector is circumnavigated in the opposite direction. (If round line joins are being used, this code is disabled because the line join will always cover the negative sector.) o When a curve is split, the arcs may not join smoothly (especially if the curve turns sharply back on itself). Changes in direction between adjacent arcs were not handled. A round corner is now added if the deviation from one arc to the next is greater than a suitable threshold. o The current direction wasn't retained if a the outline contained a zero length lineto or a curve that was determined to be `basically a point'. This could cause a spurious join to be added. o Cubics with close control points could be mishandled. All eight cases are now distinguished correctly. Other improvements ------------------ o Borders for cubic curves could be too `flat'. FT_SMALL_CUBIC_THRESHOLD has been reduced a little to prevent this. o The handling and use of movable points has been simplified a little. o Various values are now computed only if the results are actually needed. o The directions of the outer and inner borders have been swapped, as recommended by Graham Asher. * src/base/ftstroke.c: Revised. * include/freetype/ftstroke.h: Updated.
2011-07-02 12:09:52 +02:00
if ( close1 )
{
if ( close2 )
{
[ftstroke] Major revision. The main problems ----------------- o If FT_STROKER_LINEJOIN_BEVEL was specified, unlimited miter joins (not bevel joins) were generated. Indeed, the meanings of `miter' and `bevel' were incorrectly reversed (consistently) in both the code and comments. o The way bevel joins were constructed (whether specified explicitly, or created as a result of exceeding the miter limit) did not match what is required for stroked text in PostScript or PDF. The main fixes -------------- o The behaviour of FT_STROKER_LINEJOIN_BEVEL has been corrected. o A new line join style, FT_STROKER_LINEJOIN_MITER_FIXED, has been introduced to support PostScript and PDF miter joins. o FT_STROKER_LINEJOIN_MITER_VARIABLE has been introduced as an alias for FT_STROKER_LINEJOIN_MITER. Additionally, a variety of stroking errors have been fixed. These would cause various artifacts (including points `at infinity'), especially when stroking poor quality fonts. See http://lists.gnu.org/archive/html/freetype-devel/2011-07/msg00001.html for example documents. The FreeType stroker now produces results very similar to that produced by GhostScript and Distiller for these fonts. Other problems -------------- The following problems have been resolved: o Inside corners could be generated incorrectly. Intersecting the inside corner could cause a missing triangular area and other effects. The intersection point can only be used if the join is between two lines and both lines are long enough. The `optimization' condition in `ft_stroker_inside' has been corrected; this requires the line length to be passed into various functions and stored in `FT_StrokerRec'. o Incorrect cubic curves could be generated. The angle calculations in `FT_Stroker_CubicTo' have been corrected to handle the case of the curve crossing the +/-PI direction. o If the border radius was greater than the radius of curvature of a curve, then the negative sector would end up outside (not inside) the border. This situation is now recognized and the negative sector is circumnavigated in the opposite direction. (If round line joins are being used, this code is disabled because the line join will always cover the negative sector.) o When a curve is split, the arcs may not join smoothly (especially if the curve turns sharply back on itself). Changes in direction between adjacent arcs were not handled. A round corner is now added if the deviation from one arc to the next is greater than a suitable threshold. o The current direction wasn't retained if a the outline contained a zero length lineto or a curve that was determined to be `basically a point'. This could cause a spurious join to be added. o Cubics with close control points could be mishandled. All eight cases are now distinguished correctly. Other improvements ------------------ o Borders for cubic curves could be too `flat'. FT_SMALL_CUBIC_THRESHOLD has been reduced a little to prevent this. o The handling and use of movable points has been simplified a little. o Various values are now computed only if the results are actually needed. o The directions of the outer and inner borders have been swapped, as recommended by Graham Asher. * src/base/ftstroke.c: Revised. * include/freetype/ftstroke.h: Updated.
2011-07-02 12:09:52 +02:00
if ( close3 )
{
/* basically a point; */
/* do nothing to retain original direction */
}
else /* !close3 */
{
*angle_in =
*angle_mid =
*angle_out = FT_Atan2( d3.x, d3.y );
}
}
[ftstroke] Major revision. The main problems ----------------- o If FT_STROKER_LINEJOIN_BEVEL was specified, unlimited miter joins (not bevel joins) were generated. Indeed, the meanings of `miter' and `bevel' were incorrectly reversed (consistently) in both the code and comments. o The way bevel joins were constructed (whether specified explicitly, or created as a result of exceeding the miter limit) did not match what is required for stroked text in PostScript or PDF. The main fixes -------------- o The behaviour of FT_STROKER_LINEJOIN_BEVEL has been corrected. o A new line join style, FT_STROKER_LINEJOIN_MITER_FIXED, has been introduced to support PostScript and PDF miter joins. o FT_STROKER_LINEJOIN_MITER_VARIABLE has been introduced as an alias for FT_STROKER_LINEJOIN_MITER. Additionally, a variety of stroking errors have been fixed. These would cause various artifacts (including points `at infinity'), especially when stroking poor quality fonts. See http://lists.gnu.org/archive/html/freetype-devel/2011-07/msg00001.html for example documents. The FreeType stroker now produces results very similar to that produced by GhostScript and Distiller for these fonts. Other problems -------------- The following problems have been resolved: o Inside corners could be generated incorrectly. Intersecting the inside corner could cause a missing triangular area and other effects. The intersection point can only be used if the join is between two lines and both lines are long enough. The `optimization' condition in `ft_stroker_inside' has been corrected; this requires the line length to be passed into various functions and stored in `FT_StrokerRec'. o Incorrect cubic curves could be generated. The angle calculations in `FT_Stroker_CubicTo' have been corrected to handle the case of the curve crossing the +/-PI direction. o If the border radius was greater than the radius of curvature of a curve, then the negative sector would end up outside (not inside) the border. This situation is now recognized and the negative sector is circumnavigated in the opposite direction. (If round line joins are being used, this code is disabled because the line join will always cover the negative sector.) o When a curve is split, the arcs may not join smoothly (especially if the curve turns sharply back on itself). Changes in direction between adjacent arcs were not handled. A round corner is now added if the deviation from one arc to the next is greater than a suitable threshold. o The current direction wasn't retained if a the outline contained a zero length lineto or a curve that was determined to be `basically a point'. This could cause a spurious join to be added. o Cubics with close control points could be mishandled. All eight cases are now distinguished correctly. Other improvements ------------------ o Borders for cubic curves could be too `flat'. FT_SMALL_CUBIC_THRESHOLD has been reduced a little to prevent this. o The handling and use of movable points has been simplified a little. o Various values are now computed only if the results are actually needed. o The directions of the outer and inner borders have been swapped, as recommended by Graham Asher. * src/base/ftstroke.c: Revised. * include/freetype/ftstroke.h: Updated.
2011-07-02 12:09:52 +02:00
else /* !close2 */
{
[ftstroke] Major revision. The main problems ----------------- o If FT_STROKER_LINEJOIN_BEVEL was specified, unlimited miter joins (not bevel joins) were generated. Indeed, the meanings of `miter' and `bevel' were incorrectly reversed (consistently) in both the code and comments. o The way bevel joins were constructed (whether specified explicitly, or created as a result of exceeding the miter limit) did not match what is required for stroked text in PostScript or PDF. The main fixes -------------- o The behaviour of FT_STROKER_LINEJOIN_BEVEL has been corrected. o A new line join style, FT_STROKER_LINEJOIN_MITER_FIXED, has been introduced to support PostScript and PDF miter joins. o FT_STROKER_LINEJOIN_MITER_VARIABLE has been introduced as an alias for FT_STROKER_LINEJOIN_MITER. Additionally, a variety of stroking errors have been fixed. These would cause various artifacts (including points `at infinity'), especially when stroking poor quality fonts. See http://lists.gnu.org/archive/html/freetype-devel/2011-07/msg00001.html for example documents. The FreeType stroker now produces results very similar to that produced by GhostScript and Distiller for these fonts. Other problems -------------- The following problems have been resolved: o Inside corners could be generated incorrectly. Intersecting the inside corner could cause a missing triangular area and other effects. The intersection point can only be used if the join is between two lines and both lines are long enough. The `optimization' condition in `ft_stroker_inside' has been corrected; this requires the line length to be passed into various functions and stored in `FT_StrokerRec'. o Incorrect cubic curves could be generated. The angle calculations in `FT_Stroker_CubicTo' have been corrected to handle the case of the curve crossing the +/-PI direction. o If the border radius was greater than the radius of curvature of a curve, then the negative sector would end up outside (not inside) the border. This situation is now recognized and the negative sector is circumnavigated in the opposite direction. (If round line joins are being used, this code is disabled because the line join will always cover the negative sector.) o When a curve is split, the arcs may not join smoothly (especially if the curve turns sharply back on itself). Changes in direction between adjacent arcs were not handled. A round corner is now added if the deviation from one arc to the next is greater than a suitable threshold. o The current direction wasn't retained if a the outline contained a zero length lineto or a curve that was determined to be `basically a point'. This could cause a spurious join to be added. o Cubics with close control points could be mishandled. All eight cases are now distinguished correctly. Other improvements ------------------ o Borders for cubic curves could be too `flat'. FT_SMALL_CUBIC_THRESHOLD has been reduced a little to prevent this. o The handling and use of movable points has been simplified a little. o Various values are now computed only if the results are actually needed. o The directions of the outer and inner borders have been swapped, as recommended by Graham Asher. * src/base/ftstroke.c: Revised. * include/freetype/ftstroke.h: Updated.
2011-07-02 12:09:52 +02:00
if ( close3 )
{
*angle_in =
*angle_mid =
*angle_out = FT_Atan2( d2.x, d2.y );
}
else /* !close3 */
{
*angle_in =
*angle_mid = FT_Atan2( d2.x, d2.y );
*angle_out = FT_Atan2( d3.x, d3.y );
}
}
}
[ftstroke] Major revision. The main problems ----------------- o If FT_STROKER_LINEJOIN_BEVEL was specified, unlimited miter joins (not bevel joins) were generated. Indeed, the meanings of `miter' and `bevel' were incorrectly reversed (consistently) in both the code and comments. o The way bevel joins were constructed (whether specified explicitly, or created as a result of exceeding the miter limit) did not match what is required for stroked text in PostScript or PDF. The main fixes -------------- o The behaviour of FT_STROKER_LINEJOIN_BEVEL has been corrected. o A new line join style, FT_STROKER_LINEJOIN_MITER_FIXED, has been introduced to support PostScript and PDF miter joins. o FT_STROKER_LINEJOIN_MITER_VARIABLE has been introduced as an alias for FT_STROKER_LINEJOIN_MITER. Additionally, a variety of stroking errors have been fixed. These would cause various artifacts (including points `at infinity'), especially when stroking poor quality fonts. See http://lists.gnu.org/archive/html/freetype-devel/2011-07/msg00001.html for example documents. The FreeType stroker now produces results very similar to that produced by GhostScript and Distiller for these fonts. Other problems -------------- The following problems have been resolved: o Inside corners could be generated incorrectly. Intersecting the inside corner could cause a missing triangular area and other effects. The intersection point can only be used if the join is between two lines and both lines are long enough. The `optimization' condition in `ft_stroker_inside' has been corrected; this requires the line length to be passed into various functions and stored in `FT_StrokerRec'. o Incorrect cubic curves could be generated. The angle calculations in `FT_Stroker_CubicTo' have been corrected to handle the case of the curve crossing the +/-PI direction. o If the border radius was greater than the radius of curvature of a curve, then the negative sector would end up outside (not inside) the border. This situation is now recognized and the negative sector is circumnavigated in the opposite direction. (If round line joins are being used, this code is disabled because the line join will always cover the negative sector.) o When a curve is split, the arcs may not join smoothly (especially if the curve turns sharply back on itself). Changes in direction between adjacent arcs were not handled. A round corner is now added if the deviation from one arc to the next is greater than a suitable threshold. o The current direction wasn't retained if a the outline contained a zero length lineto or a curve that was determined to be `basically a point'. This could cause a spurious join to be added. o Cubics with close control points could be mishandled. All eight cases are now distinguished correctly. Other improvements ------------------ o Borders for cubic curves could be too `flat'. FT_SMALL_CUBIC_THRESHOLD has been reduced a little to prevent this. o The handling and use of movable points has been simplified a little. o Various values are now computed only if the results are actually needed. o The directions of the outer and inner borders have been swapped, as recommended by Graham Asher. * src/base/ftstroke.c: Revised. * include/freetype/ftstroke.h: Updated.
2011-07-02 12:09:52 +02:00
else /* !close1 */
{
[ftstroke] Major revision. The main problems ----------------- o If FT_STROKER_LINEJOIN_BEVEL was specified, unlimited miter joins (not bevel joins) were generated. Indeed, the meanings of `miter' and `bevel' were incorrectly reversed (consistently) in both the code and comments. o The way bevel joins were constructed (whether specified explicitly, or created as a result of exceeding the miter limit) did not match what is required for stroked text in PostScript or PDF. The main fixes -------------- o The behaviour of FT_STROKER_LINEJOIN_BEVEL has been corrected. o A new line join style, FT_STROKER_LINEJOIN_MITER_FIXED, has been introduced to support PostScript and PDF miter joins. o FT_STROKER_LINEJOIN_MITER_VARIABLE has been introduced as an alias for FT_STROKER_LINEJOIN_MITER. Additionally, a variety of stroking errors have been fixed. These would cause various artifacts (including points `at infinity'), especially when stroking poor quality fonts. See http://lists.gnu.org/archive/html/freetype-devel/2011-07/msg00001.html for example documents. The FreeType stroker now produces results very similar to that produced by GhostScript and Distiller for these fonts. Other problems -------------- The following problems have been resolved: o Inside corners could be generated incorrectly. Intersecting the inside corner could cause a missing triangular area and other effects. The intersection point can only be used if the join is between two lines and both lines are long enough. The `optimization' condition in `ft_stroker_inside' has been corrected; this requires the line length to be passed into various functions and stored in `FT_StrokerRec'. o Incorrect cubic curves could be generated. The angle calculations in `FT_Stroker_CubicTo' have been corrected to handle the case of the curve crossing the +/-PI direction. o If the border radius was greater than the radius of curvature of a curve, then the negative sector would end up outside (not inside) the border. This situation is now recognized and the negative sector is circumnavigated in the opposite direction. (If round line joins are being used, this code is disabled because the line join will always cover the negative sector.) o When a curve is split, the arcs may not join smoothly (especially if the curve turns sharply back on itself). Changes in direction between adjacent arcs were not handled. A round corner is now added if the deviation from one arc to the next is greater than a suitable threshold. o The current direction wasn't retained if a the outline contained a zero length lineto or a curve that was determined to be `basically a point'. This could cause a spurious join to be added. o Cubics with close control points could be mishandled. All eight cases are now distinguished correctly. Other improvements ------------------ o Borders for cubic curves could be too `flat'. FT_SMALL_CUBIC_THRESHOLD has been reduced a little to prevent this. o The handling and use of movable points has been simplified a little. o Various values are now computed only if the results are actually needed. o The directions of the outer and inner borders have been swapped, as recommended by Graham Asher. * src/base/ftstroke.c: Revised. * include/freetype/ftstroke.h: Updated.
2011-07-02 12:09:52 +02:00
if ( close2 )
{
if ( close3 )
{
*angle_in =
*angle_mid =
*angle_out = FT_Atan2( d1.x, d1.y );
}
else /* !close3 */
{
*angle_in = FT_Atan2( d1.x, d1.y );
*angle_out = FT_Atan2( d3.x, d3.y );
*angle_mid = ft_angle_mean( *angle_in, *angle_out );
}
}
else /* !close2 */
{
if ( close3 )
{
*angle_in = FT_Atan2( d1.x, d1.y );
*angle_mid =
*angle_out = FT_Atan2( d2.x, d2.y );
}
else /* !close3 */
{
*angle_in = FT_Atan2( d1.x, d1.y );
*angle_mid = FT_Atan2( d2.x, d2.y );
*angle_out = FT_Atan2( d3.x, d3.y );
}
}
}
theta1 = ft_pos_abs( FT_Angle_Diff( *angle_in, *angle_mid ) );
theta2 = ft_pos_abs( FT_Angle_Diff( *angle_mid, *angle_out ) );
return FT_BOOL( theta1 < FT_SMALL_CUBIC_THRESHOLD &&
theta2 < FT_SMALL_CUBIC_THRESHOLD );
}
[ftstroke] Major revision. The main problems ----------------- o If FT_STROKER_LINEJOIN_BEVEL was specified, unlimited miter joins (not bevel joins) were generated. Indeed, the meanings of `miter' and `bevel' were incorrectly reversed (consistently) in both the code and comments. o The way bevel joins were constructed (whether specified explicitly, or created as a result of exceeding the miter limit) did not match what is required for stroked text in PostScript or PDF. The main fixes -------------- o The behaviour of FT_STROKER_LINEJOIN_BEVEL has been corrected. o A new line join style, FT_STROKER_LINEJOIN_MITER_FIXED, has been introduced to support PostScript and PDF miter joins. o FT_STROKER_LINEJOIN_MITER_VARIABLE has been introduced as an alias for FT_STROKER_LINEJOIN_MITER. Additionally, a variety of stroking errors have been fixed. These would cause various artifacts (including points `at infinity'), especially when stroking poor quality fonts. See http://lists.gnu.org/archive/html/freetype-devel/2011-07/msg00001.html for example documents. The FreeType stroker now produces results very similar to that produced by GhostScript and Distiller for these fonts. Other problems -------------- The following problems have been resolved: o Inside corners could be generated incorrectly. Intersecting the inside corner could cause a missing triangular area and other effects. The intersection point can only be used if the join is between two lines and both lines are long enough. The `optimization' condition in `ft_stroker_inside' has been corrected; this requires the line length to be passed into various functions and stored in `FT_StrokerRec'. o Incorrect cubic curves could be generated. The angle calculations in `FT_Stroker_CubicTo' have been corrected to handle the case of the curve crossing the +/-PI direction. o If the border radius was greater than the radius of curvature of a curve, then the negative sector would end up outside (not inside) the border. This situation is now recognized and the negative sector is circumnavigated in the opposite direction. (If round line joins are being used, this code is disabled because the line join will always cover the negative sector.) o When a curve is split, the arcs may not join smoothly (especially if the curve turns sharply back on itself). Changes in direction between adjacent arcs were not handled. A round corner is now added if the deviation from one arc to the next is greater than a suitable threshold. o The current direction wasn't retained if a the outline contained a zero length lineto or a curve that was determined to be `basically a point'. This could cause a spurious join to be added. o Cubics with close control points could be mishandled. All eight cases are now distinguished correctly. Other improvements ------------------ o Borders for cubic curves could be too `flat'. FT_SMALL_CUBIC_THRESHOLD has been reduced a little to prevent this. o The handling and use of movable points has been simplified a little. o Various values are now computed only if the results are actually needed. o The directions of the outer and inner borders have been swapped, as recommended by Graham Asher. * src/base/ftstroke.c: Revised. * include/freetype/ftstroke.h: Updated.
2011-07-02 12:09:52 +02:00
/*************************************************************************/
/*************************************************************************/
/***** *****/
/***** STROKE BORDERS *****/
/***** *****/
/*************************************************************************/
/*************************************************************************/
2008-05-29 00:17:28 +02:00
typedef enum FT_StrokeTags_
{
FT_STROKE_TAG_ON = 1, /* on-curve point */
FT_STROKE_TAG_CUBIC = 2, /* cubic off-point */
FT_STROKE_TAG_BEGIN = 4, /* sub-path start */
FT_STROKE_TAG_END = 8 /* sub-path end */
} FT_StrokeTags;
[ftstroke] Major revision. The main problems ----------------- o If FT_STROKER_LINEJOIN_BEVEL was specified, unlimited miter joins (not bevel joins) were generated. Indeed, the meanings of `miter' and `bevel' were incorrectly reversed (consistently) in both the code and comments. o The way bevel joins were constructed (whether specified explicitly, or created as a result of exceeding the miter limit) did not match what is required for stroked text in PostScript or PDF. The main fixes -------------- o The behaviour of FT_STROKER_LINEJOIN_BEVEL has been corrected. o A new line join style, FT_STROKER_LINEJOIN_MITER_FIXED, has been introduced to support PostScript and PDF miter joins. o FT_STROKER_LINEJOIN_MITER_VARIABLE has been introduced as an alias for FT_STROKER_LINEJOIN_MITER. Additionally, a variety of stroking errors have been fixed. These would cause various artifacts (including points `at infinity'), especially when stroking poor quality fonts. See http://lists.gnu.org/archive/html/freetype-devel/2011-07/msg00001.html for example documents. The FreeType stroker now produces results very similar to that produced by GhostScript and Distiller for these fonts. Other problems -------------- The following problems have been resolved: o Inside corners could be generated incorrectly. Intersecting the inside corner could cause a missing triangular area and other effects. The intersection point can only be used if the join is between two lines and both lines are long enough. The `optimization' condition in `ft_stroker_inside' has been corrected; this requires the line length to be passed into various functions and stored in `FT_StrokerRec'. o Incorrect cubic curves could be generated. The angle calculations in `FT_Stroker_CubicTo' have been corrected to handle the case of the curve crossing the +/-PI direction. o If the border radius was greater than the radius of curvature of a curve, then the negative sector would end up outside (not inside) the border. This situation is now recognized and the negative sector is circumnavigated in the opposite direction. (If round line joins are being used, this code is disabled because the line join will always cover the negative sector.) o When a curve is split, the arcs may not join smoothly (especially if the curve turns sharply back on itself). Changes in direction between adjacent arcs were not handled. A round corner is now added if the deviation from one arc to the next is greater than a suitable threshold. o The current direction wasn't retained if a the outline contained a zero length lineto or a curve that was determined to be `basically a point'. This could cause a spurious join to be added. o Cubics with close control points could be mishandled. All eight cases are now distinguished correctly. Other improvements ------------------ o Borders for cubic curves could be too `flat'. FT_SMALL_CUBIC_THRESHOLD has been reduced a little to prevent this. o The handling and use of movable points has been simplified a little. o Various values are now computed only if the results are actually needed. o The directions of the outer and inner borders have been swapped, as recommended by Graham Asher. * src/base/ftstroke.c: Revised. * include/freetype/ftstroke.h: Updated.
2011-07-02 12:09:52 +02:00
#define FT_STROKE_TAG_BEGIN_END ( FT_STROKE_TAG_BEGIN | FT_STROKE_TAG_END )
typedef struct FT_StrokeBorderRec_
{
FT_UInt num_points;
FT_UInt max_points;
FT_Vector* points;
FT_Byte* tags;
[ftstroke] Major revision. The main problems ----------------- o If FT_STROKER_LINEJOIN_BEVEL was specified, unlimited miter joins (not bevel joins) were generated. Indeed, the meanings of `miter' and `bevel' were incorrectly reversed (consistently) in both the code and comments. o The way bevel joins were constructed (whether specified explicitly, or created as a result of exceeding the miter limit) did not match what is required for stroked text in PostScript or PDF. The main fixes -------------- o The behaviour of FT_STROKER_LINEJOIN_BEVEL has been corrected. o A new line join style, FT_STROKER_LINEJOIN_MITER_FIXED, has been introduced to support PostScript and PDF miter joins. o FT_STROKER_LINEJOIN_MITER_VARIABLE has been introduced as an alias for FT_STROKER_LINEJOIN_MITER. Additionally, a variety of stroking errors have been fixed. These would cause various artifacts (including points `at infinity'), especially when stroking poor quality fonts. See http://lists.gnu.org/archive/html/freetype-devel/2011-07/msg00001.html for example documents. The FreeType stroker now produces results very similar to that produced by GhostScript and Distiller for these fonts. Other problems -------------- The following problems have been resolved: o Inside corners could be generated incorrectly. Intersecting the inside corner could cause a missing triangular area and other effects. The intersection point can only be used if the join is between two lines and both lines are long enough. The `optimization' condition in `ft_stroker_inside' has been corrected; this requires the line length to be passed into various functions and stored in `FT_StrokerRec'. o Incorrect cubic curves could be generated. The angle calculations in `FT_Stroker_CubicTo' have been corrected to handle the case of the curve crossing the +/-PI direction. o If the border radius was greater than the radius of curvature of a curve, then the negative sector would end up outside (not inside) the border. This situation is now recognized and the negative sector is circumnavigated in the opposite direction. (If round line joins are being used, this code is disabled because the line join will always cover the negative sector.) o When a curve is split, the arcs may not join smoothly (especially if the curve turns sharply back on itself). Changes in direction between adjacent arcs were not handled. A round corner is now added if the deviation from one arc to the next is greater than a suitable threshold. o The current direction wasn't retained if a the outline contained a zero length lineto or a curve that was determined to be `basically a point'. This could cause a spurious join to be added. o Cubics with close control points could be mishandled. All eight cases are now distinguished correctly. Other improvements ------------------ o Borders for cubic curves could be too `flat'. FT_SMALL_CUBIC_THRESHOLD has been reduced a little to prevent this. o The handling and use of movable points has been simplified a little. o Various values are now computed only if the results are actually needed. o The directions of the outer and inner borders have been swapped, as recommended by Graham Asher. * src/base/ftstroke.c: Revised. * include/freetype/ftstroke.h: Updated.
2011-07-02 12:09:52 +02:00
FT_Bool movable; /* TRUE for ends of lineto borders */
FT_Int start; /* index of current sub-path start point */
FT_Memory memory;
FT_Bool valid;
} FT_StrokeBorderRec, *FT_StrokeBorder;
static FT_Error
ft_stroke_border_grow( FT_StrokeBorder border,
FT_UInt new_points )
{
FT_UInt old_max = border->max_points;
FT_UInt new_max = border->num_points + new_points;
2008-09-16 19:32:02 +02:00
FT_Error error = FT_Err_Ok;
if ( new_max > old_max )
{
FT_UInt cur_max = old_max;
FT_Memory memory = border->memory;
while ( cur_max < new_max )
cur_max += ( cur_max >> 1 ) + 16;
if ( FT_RENEW_ARRAY( border->points, old_max, cur_max ) ||
FT_RENEW_ARRAY( border->tags, old_max, cur_max ) )
goto Exit;
border->max_points = cur_max;
}
2008-09-16 19:32:02 +02:00
Exit:
return error;
}
static void
ft_stroke_border_close( FT_StrokeBorder border,
FT_Bool reverse )
{
FT_UInt start = border->start;
FT_UInt count = border->num_points;
FT_ASSERT( border->start >= 0 );
/* don't record empty paths! */
if ( count <= start + 1U )
border->num_points = start;
else
{
/* copy the last point to the start of this sub-path, since */
/* it contains the `adjusted' starting coordinates */
border->num_points = --count;
border->points[start] = border->points[count];
if ( reverse )
{
/* reverse the points */
{
FT_Vector* vec1 = border->points + start + 1;
FT_Vector* vec2 = border->points + count - 1;
for ( ; vec1 < vec2; vec1++, vec2-- )
{
FT_Vector tmp;
tmp = *vec1;
*vec1 = *vec2;
*vec2 = tmp;
}
}
/* then the tags */
{
FT_Byte* tag1 = border->tags + start + 1;
FT_Byte* tag2 = border->tags + count - 1;
for ( ; tag1 < tag2; tag1++, tag2-- )
{
FT_Byte tmp;
tmp = *tag1;
*tag1 = *tag2;
*tag2 = tmp;
}
}
}
border->tags[start ] |= FT_STROKE_TAG_BEGIN;
border->tags[count - 1] |= FT_STROKE_TAG_END;
}
border->start = -1;
2008-09-16 19:32:02 +02:00
border->movable = FALSE;
}
static FT_Error
ft_stroke_border_lineto( FT_StrokeBorder border,
FT_Vector* to,
FT_Bool movable )
{
2008-09-16 19:32:02 +02:00
FT_Error error = FT_Err_Ok;
FT_ASSERT( border->start >= 0 );
if ( border->movable )
{
/* move last point */
border->points[border->num_points - 1] = *to;
}
else
{
[ftstroke] Major revision. The main problems ----------------- o If FT_STROKER_LINEJOIN_BEVEL was specified, unlimited miter joins (not bevel joins) were generated. Indeed, the meanings of `miter' and `bevel' were incorrectly reversed (consistently) in both the code and comments. o The way bevel joins were constructed (whether specified explicitly, or created as a result of exceeding the miter limit) did not match what is required for stroked text in PostScript or PDF. The main fixes -------------- o The behaviour of FT_STROKER_LINEJOIN_BEVEL has been corrected. o A new line join style, FT_STROKER_LINEJOIN_MITER_FIXED, has been introduced to support PostScript and PDF miter joins. o FT_STROKER_LINEJOIN_MITER_VARIABLE has been introduced as an alias for FT_STROKER_LINEJOIN_MITER. Additionally, a variety of stroking errors have been fixed. These would cause various artifacts (including points `at infinity'), especially when stroking poor quality fonts. See http://lists.gnu.org/archive/html/freetype-devel/2011-07/msg00001.html for example documents. The FreeType stroker now produces results very similar to that produced by GhostScript and Distiller for these fonts. Other problems -------------- The following problems have been resolved: o Inside corners could be generated incorrectly. Intersecting the inside corner could cause a missing triangular area and other effects. The intersection point can only be used if the join is between two lines and both lines are long enough. The `optimization' condition in `ft_stroker_inside' has been corrected; this requires the line length to be passed into various functions and stored in `FT_StrokerRec'. o Incorrect cubic curves could be generated. The angle calculations in `FT_Stroker_CubicTo' have been corrected to handle the case of the curve crossing the +/-PI direction. o If the border radius was greater than the radius of curvature of a curve, then the negative sector would end up outside (not inside) the border. This situation is now recognized and the negative sector is circumnavigated in the opposite direction. (If round line joins are being used, this code is disabled because the line join will always cover the negative sector.) o When a curve is split, the arcs may not join smoothly (especially if the curve turns sharply back on itself). Changes in direction between adjacent arcs were not handled. A round corner is now added if the deviation from one arc to the next is greater than a suitable threshold. o The current direction wasn't retained if a the outline contained a zero length lineto or a curve that was determined to be `basically a point'. This could cause a spurious join to be added. o Cubics with close control points could be mishandled. All eight cases are now distinguished correctly. Other improvements ------------------ o Borders for cubic curves could be too `flat'. FT_SMALL_CUBIC_THRESHOLD has been reduced a little to prevent this. o The handling and use of movable points has been simplified a little. o Various values are now computed only if the results are actually needed. o The directions of the outer and inner borders have been swapped, as recommended by Graham Asher. * src/base/ftstroke.c: Revised. * include/freetype/ftstroke.h: Updated.
2011-07-02 12:09:52 +02:00
/* don't add zero-length lineto */
if ( border->num_points > 0 &&
FT_IS_SMALL( border->points[border->num_points - 1].x - to->x ) &&
FT_IS_SMALL( border->points[border->num_points - 1].y - to->y ) )
return error;
/* add one point */
error = ft_stroke_border_grow( border, 1 );
if ( !error )
{
FT_Vector* vec = border->points + border->num_points;
FT_Byte* tag = border->tags + border->num_points;
vec[0] = *to;
tag[0] = FT_STROKE_TAG_ON;
border->num_points += 1;
}
}
border->movable = movable;
return error;
}
static FT_Error
ft_stroke_border_conicto( FT_StrokeBorder border,
FT_Vector* control,
FT_Vector* to )
{
FT_Error error;
FT_ASSERT( border->start >= 0 );
error = ft_stroke_border_grow( border, 2 );
if ( !error )
{
FT_Vector* vec = border->points + border->num_points;
FT_Byte* tag = border->tags + border->num_points;
[ftstroke] Major revision. The main problems ----------------- o If FT_STROKER_LINEJOIN_BEVEL was specified, unlimited miter joins (not bevel joins) were generated. Indeed, the meanings of `miter' and `bevel' were incorrectly reversed (consistently) in both the code and comments. o The way bevel joins were constructed (whether specified explicitly, or created as a result of exceeding the miter limit) did not match what is required for stroked text in PostScript or PDF. The main fixes -------------- o The behaviour of FT_STROKER_LINEJOIN_BEVEL has been corrected. o A new line join style, FT_STROKER_LINEJOIN_MITER_FIXED, has been introduced to support PostScript and PDF miter joins. o FT_STROKER_LINEJOIN_MITER_VARIABLE has been introduced as an alias for FT_STROKER_LINEJOIN_MITER. Additionally, a variety of stroking errors have been fixed. These would cause various artifacts (including points `at infinity'), especially when stroking poor quality fonts. See http://lists.gnu.org/archive/html/freetype-devel/2011-07/msg00001.html for example documents. The FreeType stroker now produces results very similar to that produced by GhostScript and Distiller for these fonts. Other problems -------------- The following problems have been resolved: o Inside corners could be generated incorrectly. Intersecting the inside corner could cause a missing triangular area and other effects. The intersection point can only be used if the join is between two lines and both lines are long enough. The `optimization' condition in `ft_stroker_inside' has been corrected; this requires the line length to be passed into various functions and stored in `FT_StrokerRec'. o Incorrect cubic curves could be generated. The angle calculations in `FT_Stroker_CubicTo' have been corrected to handle the case of the curve crossing the +/-PI direction. o If the border radius was greater than the radius of curvature of a curve, then the negative sector would end up outside (not inside) the border. This situation is now recognized and the negative sector is circumnavigated in the opposite direction. (If round line joins are being used, this code is disabled because the line join will always cover the negative sector.) o When a curve is split, the arcs may not join smoothly (especially if the curve turns sharply back on itself). Changes in direction between adjacent arcs were not handled. A round corner is now added if the deviation from one arc to the next is greater than a suitable threshold. o The current direction wasn't retained if a the outline contained a zero length lineto or a curve that was determined to be `basically a point'. This could cause a spurious join to be added. o Cubics with close control points could be mishandled. All eight cases are now distinguished correctly. Other improvements ------------------ o Borders for cubic curves could be too `flat'. FT_SMALL_CUBIC_THRESHOLD has been reduced a little to prevent this. o The handling and use of movable points has been simplified a little. o Various values are now computed only if the results are actually needed. o The directions of the outer and inner borders have been swapped, as recommended by Graham Asher. * src/base/ftstroke.c: Revised. * include/freetype/ftstroke.h: Updated.
2011-07-02 12:09:52 +02:00
vec[0] = *control;
vec[1] = *to;
tag[0] = 0;
tag[1] = FT_STROKE_TAG_ON;
border->num_points += 2;
}
[ftstroke] Major revision. The main problems ----------------- o If FT_STROKER_LINEJOIN_BEVEL was specified, unlimited miter joins (not bevel joins) were generated. Indeed, the meanings of `miter' and `bevel' were incorrectly reversed (consistently) in both the code and comments. o The way bevel joins were constructed (whether specified explicitly, or created as a result of exceeding the miter limit) did not match what is required for stroked text in PostScript or PDF. The main fixes -------------- o The behaviour of FT_STROKER_LINEJOIN_BEVEL has been corrected. o A new line join style, FT_STROKER_LINEJOIN_MITER_FIXED, has been introduced to support PostScript and PDF miter joins. o FT_STROKER_LINEJOIN_MITER_VARIABLE has been introduced as an alias for FT_STROKER_LINEJOIN_MITER. Additionally, a variety of stroking errors have been fixed. These would cause various artifacts (including points `at infinity'), especially when stroking poor quality fonts. See http://lists.gnu.org/archive/html/freetype-devel/2011-07/msg00001.html for example documents. The FreeType stroker now produces results very similar to that produced by GhostScript and Distiller for these fonts. Other problems -------------- The following problems have been resolved: o Inside corners could be generated incorrectly. Intersecting the inside corner could cause a missing triangular area and other effects. The intersection point can only be used if the join is between two lines and both lines are long enough. The `optimization' condition in `ft_stroker_inside' has been corrected; this requires the line length to be passed into various functions and stored in `FT_StrokerRec'. o Incorrect cubic curves could be generated. The angle calculations in `FT_Stroker_CubicTo' have been corrected to handle the case of the curve crossing the +/-PI direction. o If the border radius was greater than the radius of curvature of a curve, then the negative sector would end up outside (not inside) the border. This situation is now recognized and the negative sector is circumnavigated in the opposite direction. (If round line joins are being used, this code is disabled because the line join will always cover the negative sector.) o When a curve is split, the arcs may not join smoothly (especially if the curve turns sharply back on itself). Changes in direction between adjacent arcs were not handled. A round corner is now added if the deviation from one arc to the next is greater than a suitable threshold. o The current direction wasn't retained if a the outline contained a zero length lineto or a curve that was determined to be `basically a point'. This could cause a spurious join to be added. o Cubics with close control points could be mishandled. All eight cases are now distinguished correctly. Other improvements ------------------ o Borders for cubic curves could be too `flat'. FT_SMALL_CUBIC_THRESHOLD has been reduced a little to prevent this. o The handling and use of movable points has been simplified a little. o Various values are now computed only if the results are actually needed. o The directions of the outer and inner borders have been swapped, as recommended by Graham Asher. * src/base/ftstroke.c: Revised. * include/freetype/ftstroke.h: Updated.
2011-07-02 12:09:52 +02:00
2008-09-16 19:32:02 +02:00
border->movable = FALSE;
[ftstroke] Major revision. The main problems ----------------- o If FT_STROKER_LINEJOIN_BEVEL was specified, unlimited miter joins (not bevel joins) were generated. Indeed, the meanings of `miter' and `bevel' were incorrectly reversed (consistently) in both the code and comments. o The way bevel joins were constructed (whether specified explicitly, or created as a result of exceeding the miter limit) did not match what is required for stroked text in PostScript or PDF. The main fixes -------------- o The behaviour of FT_STROKER_LINEJOIN_BEVEL has been corrected. o A new line join style, FT_STROKER_LINEJOIN_MITER_FIXED, has been introduced to support PostScript and PDF miter joins. o FT_STROKER_LINEJOIN_MITER_VARIABLE has been introduced as an alias for FT_STROKER_LINEJOIN_MITER. Additionally, a variety of stroking errors have been fixed. These would cause various artifacts (including points `at infinity'), especially when stroking poor quality fonts. See http://lists.gnu.org/archive/html/freetype-devel/2011-07/msg00001.html for example documents. The FreeType stroker now produces results very similar to that produced by GhostScript and Distiller for these fonts. Other problems -------------- The following problems have been resolved: o Inside corners could be generated incorrectly. Intersecting the inside corner could cause a missing triangular area and other effects. The intersection point can only be used if the join is between two lines and both lines are long enough. The `optimization' condition in `ft_stroker_inside' has been corrected; this requires the line length to be passed into various functions and stored in `FT_StrokerRec'. o Incorrect cubic curves could be generated. The angle calculations in `FT_Stroker_CubicTo' have been corrected to handle the case of the curve crossing the +/-PI direction. o If the border radius was greater than the radius of curvature of a curve, then the negative sector would end up outside (not inside) the border. This situation is now recognized and the negative sector is circumnavigated in the opposite direction. (If round line joins are being used, this code is disabled because the line join will always cover the negative sector.) o When a curve is split, the arcs may not join smoothly (especially if the curve turns sharply back on itself). Changes in direction between adjacent arcs were not handled. A round corner is now added if the deviation from one arc to the next is greater than a suitable threshold. o The current direction wasn't retained if a the outline contained a zero length lineto or a curve that was determined to be `basically a point'. This could cause a spurious join to be added. o Cubics with close control points could be mishandled. All eight cases are now distinguished correctly. Other improvements ------------------ o Borders for cubic curves could be too `flat'. FT_SMALL_CUBIC_THRESHOLD has been reduced a little to prevent this. o The handling and use of movable points has been simplified a little. o Various values are now computed only if the results are actually needed. o The directions of the outer and inner borders have been swapped, as recommended by Graham Asher. * src/base/ftstroke.c: Revised. * include/freetype/ftstroke.h: Updated.
2011-07-02 12:09:52 +02:00
return error;
}
static FT_Error
ft_stroke_border_cubicto( FT_StrokeBorder border,
FT_Vector* control1,
FT_Vector* control2,
FT_Vector* to )
{
FT_Error error;
FT_ASSERT( border->start >= 0 );
error = ft_stroke_border_grow( border, 3 );
if ( !error )
{
FT_Vector* vec = border->points + border->num_points;
FT_Byte* tag = border->tags + border->num_points;
vec[0] = *control1;
vec[1] = *control2;
vec[2] = *to;
tag[0] = FT_STROKE_TAG_CUBIC;
tag[1] = FT_STROKE_TAG_CUBIC;
tag[2] = FT_STROKE_TAG_ON;
border->num_points += 3;
}
[ftstroke] Major revision. The main problems ----------------- o If FT_STROKER_LINEJOIN_BEVEL was specified, unlimited miter joins (not bevel joins) were generated. Indeed, the meanings of `miter' and `bevel' were incorrectly reversed (consistently) in both the code and comments. o The way bevel joins were constructed (whether specified explicitly, or created as a result of exceeding the miter limit) did not match what is required for stroked text in PostScript or PDF. The main fixes -------------- o The behaviour of FT_STROKER_LINEJOIN_BEVEL has been corrected. o A new line join style, FT_STROKER_LINEJOIN_MITER_FIXED, has been introduced to support PostScript and PDF miter joins. o FT_STROKER_LINEJOIN_MITER_VARIABLE has been introduced as an alias for FT_STROKER_LINEJOIN_MITER. Additionally, a variety of stroking errors have been fixed. These would cause various artifacts (including points `at infinity'), especially when stroking poor quality fonts. See http://lists.gnu.org/archive/html/freetype-devel/2011-07/msg00001.html for example documents. The FreeType stroker now produces results very similar to that produced by GhostScript and Distiller for these fonts. Other problems -------------- The following problems have been resolved: o Inside corners could be generated incorrectly. Intersecting the inside corner could cause a missing triangular area and other effects. The intersection point can only be used if the join is between two lines and both lines are long enough. The `optimization' condition in `ft_stroker_inside' has been corrected; this requires the line length to be passed into various functions and stored in `FT_StrokerRec'. o Incorrect cubic curves could be generated. The angle calculations in `FT_Stroker_CubicTo' have been corrected to handle the case of the curve crossing the +/-PI direction. o If the border radius was greater than the radius of curvature of a curve, then the negative sector would end up outside (not inside) the border. This situation is now recognized and the negative sector is circumnavigated in the opposite direction. (If round line joins are being used, this code is disabled because the line join will always cover the negative sector.) o When a curve is split, the arcs may not join smoothly (especially if the curve turns sharply back on itself). Changes in direction between adjacent arcs were not handled. A round corner is now added if the deviation from one arc to the next is greater than a suitable threshold. o The current direction wasn't retained if a the outline contained a zero length lineto or a curve that was determined to be `basically a point'. This could cause a spurious join to be added. o Cubics with close control points could be mishandled. All eight cases are now distinguished correctly. Other improvements ------------------ o Borders for cubic curves could be too `flat'. FT_SMALL_CUBIC_THRESHOLD has been reduced a little to prevent this. o The handling and use of movable points has been simplified a little. o Various values are now computed only if the results are actually needed. o The directions of the outer and inner borders have been swapped, as recommended by Graham Asher. * src/base/ftstroke.c: Revised. * include/freetype/ftstroke.h: Updated.
2011-07-02 12:09:52 +02:00
2008-09-16 19:32:02 +02:00
border->movable = FALSE;
[ftstroke] Major revision. The main problems ----------------- o If FT_STROKER_LINEJOIN_BEVEL was specified, unlimited miter joins (not bevel joins) were generated. Indeed, the meanings of `miter' and `bevel' were incorrectly reversed (consistently) in both the code and comments. o The way bevel joins were constructed (whether specified explicitly, or created as a result of exceeding the miter limit) did not match what is required for stroked text in PostScript or PDF. The main fixes -------------- o The behaviour of FT_STROKER_LINEJOIN_BEVEL has been corrected. o A new line join style, FT_STROKER_LINEJOIN_MITER_FIXED, has been introduced to support PostScript and PDF miter joins. o FT_STROKER_LINEJOIN_MITER_VARIABLE has been introduced as an alias for FT_STROKER_LINEJOIN_MITER. Additionally, a variety of stroking errors have been fixed. These would cause various artifacts (including points `at infinity'), especially when stroking poor quality fonts. See http://lists.gnu.org/archive/html/freetype-devel/2011-07/msg00001.html for example documents. The FreeType stroker now produces results very similar to that produced by GhostScript and Distiller for these fonts. Other problems -------------- The following problems have been resolved: o Inside corners could be generated incorrectly. Intersecting the inside corner could cause a missing triangular area and other effects. The intersection point can only be used if the join is between two lines and both lines are long enough. The `optimization' condition in `ft_stroker_inside' has been corrected; this requires the line length to be passed into various functions and stored in `FT_StrokerRec'. o Incorrect cubic curves could be generated. The angle calculations in `FT_Stroker_CubicTo' have been corrected to handle the case of the curve crossing the +/-PI direction. o If the border radius was greater than the radius of curvature of a curve, then the negative sector would end up outside (not inside) the border. This situation is now recognized and the negative sector is circumnavigated in the opposite direction. (If round line joins are being used, this code is disabled because the line join will always cover the negative sector.) o When a curve is split, the arcs may not join smoothly (especially if the curve turns sharply back on itself). Changes in direction between adjacent arcs were not handled. A round corner is now added if the deviation from one arc to the next is greater than a suitable threshold. o The current direction wasn't retained if a the outline contained a zero length lineto or a curve that was determined to be `basically a point'. This could cause a spurious join to be added. o Cubics with close control points could be mishandled. All eight cases are now distinguished correctly. Other improvements ------------------ o Borders for cubic curves could be too `flat'. FT_SMALL_CUBIC_THRESHOLD has been reduced a little to prevent this. o The handling and use of movable points has been simplified a little. o Various values are now computed only if the results are actually needed. o The directions of the outer and inner borders have been swapped, as recommended by Graham Asher. * src/base/ftstroke.c: Revised. * include/freetype/ftstroke.h: Updated.
2011-07-02 12:09:52 +02:00
return error;
}
#define FT_ARC_CUBIC_ANGLE ( FT_ANGLE_PI / 2 )
static FT_Error
ft_stroke_border_arcto( FT_StrokeBorder border,
FT_Vector* center,
FT_Fixed radius,
FT_Angle angle_start,
FT_Angle angle_diff )
{
FT_Angle total, angle, step, rotate, next, theta;
FT_Vector a, b, a2, b2;
FT_Fixed length;
2008-09-16 19:32:02 +02:00
FT_Error error = FT_Err_Ok;
/* compute start point */
FT_Vector_From_Polar( &a, radius, angle_start );
a.x += center->x;
a.y += center->y;
total = angle_diff;
angle = angle_start;
rotate = ( angle_diff >= 0 ) ? FT_ANGLE_PI2 : -FT_ANGLE_PI2;
while ( total != 0 )
{
step = total;
if ( step > FT_ARC_CUBIC_ANGLE )
step = FT_ARC_CUBIC_ANGLE;
else if ( step < -FT_ARC_CUBIC_ANGLE )
step = -FT_ARC_CUBIC_ANGLE;
next = angle + step;
theta = step;
if ( theta < 0 )
theta = -theta;
theta >>= 1;
/* compute end point */
FT_Vector_From_Polar( &b, radius, next );
b.x += center->x;
b.y += center->y;
/* compute first and second control points */
length = FT_MulDiv( radius, FT_Sin( theta ) * 4,
( 0x10000L + FT_Cos( theta ) ) * 3 );
FT_Vector_From_Polar( &a2, length, angle + rotate );
a2.x += a.x;
a2.y += a.y;
FT_Vector_From_Polar( &b2, length, next - rotate );
b2.x += b.x;
b2.y += b.y;
/* add cubic arc */
error = ft_stroke_border_cubicto( border, &a2, &b2, &b );
if ( error )
break;
/* process the rest of the arc ?? */
a = b;
total -= step;
angle = next;
}
return error;
}
static FT_Error
ft_stroke_border_moveto( FT_StrokeBorder border,
FT_Vector* to )
{
/* close current open path if any ? */
if ( border->start >= 0 )
2008-09-16 19:32:02 +02:00
ft_stroke_border_close( border, FALSE );
[ftstroke] Major revision. The main problems ----------------- o If FT_STROKER_LINEJOIN_BEVEL was specified, unlimited miter joins (not bevel joins) were generated. Indeed, the meanings of `miter' and `bevel' were incorrectly reversed (consistently) in both the code and comments. o The way bevel joins were constructed (whether specified explicitly, or created as a result of exceeding the miter limit) did not match what is required for stroked text in PostScript or PDF. The main fixes -------------- o The behaviour of FT_STROKER_LINEJOIN_BEVEL has been corrected. o A new line join style, FT_STROKER_LINEJOIN_MITER_FIXED, has been introduced to support PostScript and PDF miter joins. o FT_STROKER_LINEJOIN_MITER_VARIABLE has been introduced as an alias for FT_STROKER_LINEJOIN_MITER. Additionally, a variety of stroking errors have been fixed. These would cause various artifacts (including points `at infinity'), especially when stroking poor quality fonts. See http://lists.gnu.org/archive/html/freetype-devel/2011-07/msg00001.html for example documents. The FreeType stroker now produces results very similar to that produced by GhostScript and Distiller for these fonts. Other problems -------------- The following problems have been resolved: o Inside corners could be generated incorrectly. Intersecting the inside corner could cause a missing triangular area and other effects. The intersection point can only be used if the join is between two lines and both lines are long enough. The `optimization' condition in `ft_stroker_inside' has been corrected; this requires the line length to be passed into various functions and stored in `FT_StrokerRec'. o Incorrect cubic curves could be generated. The angle calculations in `FT_Stroker_CubicTo' have been corrected to handle the case of the curve crossing the +/-PI direction. o If the border radius was greater than the radius of curvature of a curve, then the negative sector would end up outside (not inside) the border. This situation is now recognized and the negative sector is circumnavigated in the opposite direction. (If round line joins are being used, this code is disabled because the line join will always cover the negative sector.) o When a curve is split, the arcs may not join smoothly (especially if the curve turns sharply back on itself). Changes in direction between adjacent arcs were not handled. A round corner is now added if the deviation from one arc to the next is greater than a suitable threshold. o The current direction wasn't retained if a the outline contained a zero length lineto or a curve that was determined to be `basically a point'. This could cause a spurious join to be added. o Cubics with close control points could be mishandled. All eight cases are now distinguished correctly. Other improvements ------------------ o Borders for cubic curves could be too `flat'. FT_SMALL_CUBIC_THRESHOLD has been reduced a little to prevent this. o The handling and use of movable points has been simplified a little. o Various values are now computed only if the results are actually needed. o The directions of the outer and inner borders have been swapped, as recommended by Graham Asher. * src/base/ftstroke.c: Revised. * include/freetype/ftstroke.h: Updated.
2011-07-02 12:09:52 +02:00
border->start = border->num_points;
2008-09-16 19:32:02 +02:00
border->movable = FALSE;
2008-09-16 19:32:02 +02:00
return ft_stroke_border_lineto( border, to, FALSE );
}
static void
ft_stroke_border_init( FT_StrokeBorder border,
FT_Memory memory )
{
border->memory = memory;
border->points = NULL;
border->tags = NULL;
border->num_points = 0;
border->max_points = 0;
border->start = -1;
2008-09-16 19:32:02 +02:00
border->valid = FALSE;
}
static void
ft_stroke_border_reset( FT_StrokeBorder border )
{
border->num_points = 0;
border->start = -1;
2008-09-16 19:32:02 +02:00
border->valid = FALSE;
}
static void
ft_stroke_border_done( FT_StrokeBorder border )
{
FT_Memory memory = border->memory;
FT_FREE( border->points );
FT_FREE( border->tags );
border->num_points = 0;
border->max_points = 0;
border->start = -1;
2008-09-16 19:32:02 +02:00
border->valid = FALSE;
}
static FT_Error
ft_stroke_border_get_counts( FT_StrokeBorder border,
FT_UInt *anum_points,
FT_UInt *anum_contours )
{
2008-09-16 19:32:02 +02:00
FT_Error error = FT_Err_Ok;
FT_UInt num_points = 0;
FT_UInt num_contours = 0;
FT_UInt count = border->num_points;
FT_Vector* point = border->points;
FT_Byte* tags = border->tags;
FT_Int in_contour = 0;
for ( ; count > 0; count--, num_points++, point++, tags++ )
{
if ( tags[0] & FT_STROKE_TAG_BEGIN )
{
if ( in_contour != 0 )
goto Fail;
in_contour = 1;
}
else if ( in_contour == 0 )
goto Fail;
if ( tags[0] & FT_STROKE_TAG_END )
{
in_contour = 0;
num_contours++;
}
}
if ( in_contour != 0 )
goto Fail;
2008-09-16 19:32:02 +02:00
border->valid = TRUE;
Exit:
*anum_points = num_points;
*anum_contours = num_contours;
return error;
Fail:
num_points = 0;
num_contours = 0;
goto Exit;
}
static void
ft_stroke_border_export( FT_StrokeBorder border,
FT_Outline* outline )
{
/* copy point locations */
FT_ARRAY_COPY( outline->points + outline->n_points,
border->points,
border->num_points );
/* copy tags */
{
FT_UInt count = border->num_points;
FT_Byte* read = border->tags;
FT_Byte* write = (FT_Byte*)outline->tags + outline->n_points;
for ( ; count > 0; count--, read++, write++ )
{
if ( *read & FT_STROKE_TAG_ON )
*write = FT_CURVE_TAG_ON;
else if ( *read & FT_STROKE_TAG_CUBIC )
*write = FT_CURVE_TAG_CUBIC;
else
*write = FT_CURVE_TAG_CONIC;
}
}
/* copy contours */
{
FT_UInt count = border->num_points;
FT_Byte* tags = border->tags;
FT_Short* write = outline->contours + outline->n_contours;
FT_Short idx = (FT_Short)outline->n_points;
for ( ; count > 0; count--, tags++, idx++ )
{
if ( *tags & FT_STROKE_TAG_END )
{
*write++ = idx;
outline->n_contours++;
}
}
}
[ftstroke] Major revision. The main problems ----------------- o If FT_STROKER_LINEJOIN_BEVEL was specified, unlimited miter joins (not bevel joins) were generated. Indeed, the meanings of `miter' and `bevel' were incorrectly reversed (consistently) in both the code and comments. o The way bevel joins were constructed (whether specified explicitly, or created as a result of exceeding the miter limit) did not match what is required for stroked text in PostScript or PDF. The main fixes -------------- o The behaviour of FT_STROKER_LINEJOIN_BEVEL has been corrected. o A new line join style, FT_STROKER_LINEJOIN_MITER_FIXED, has been introduced to support PostScript and PDF miter joins. o FT_STROKER_LINEJOIN_MITER_VARIABLE has been introduced as an alias for FT_STROKER_LINEJOIN_MITER. Additionally, a variety of stroking errors have been fixed. These would cause various artifacts (including points `at infinity'), especially when stroking poor quality fonts. See http://lists.gnu.org/archive/html/freetype-devel/2011-07/msg00001.html for example documents. The FreeType stroker now produces results very similar to that produced by GhostScript and Distiller for these fonts. Other problems -------------- The following problems have been resolved: o Inside corners could be generated incorrectly. Intersecting the inside corner could cause a missing triangular area and other effects. The intersection point can only be used if the join is between two lines and both lines are long enough. The `optimization' condition in `ft_stroker_inside' has been corrected; this requires the line length to be passed into various functions and stored in `FT_StrokerRec'. o Incorrect cubic curves could be generated. The angle calculations in `FT_Stroker_CubicTo' have been corrected to handle the case of the curve crossing the +/-PI direction. o If the border radius was greater than the radius of curvature of a curve, then the negative sector would end up outside (not inside) the border. This situation is now recognized and the negative sector is circumnavigated in the opposite direction. (If round line joins are being used, this code is disabled because the line join will always cover the negative sector.) o When a curve is split, the arcs may not join smoothly (especially if the curve turns sharply back on itself). Changes in direction between adjacent arcs were not handled. A round corner is now added if the deviation from one arc to the next is greater than a suitable threshold. o The current direction wasn't retained if a the outline contained a zero length lineto or a curve that was determined to be `basically a point'. This could cause a spurious join to be added. o Cubics with close control points could be mishandled. All eight cases are now distinguished correctly. Other improvements ------------------ o Borders for cubic curves could be too `flat'. FT_SMALL_CUBIC_THRESHOLD has been reduced a little to prevent this. o The handling and use of movable points has been simplified a little. o Various values are now computed only if the results are actually needed. o The directions of the outer and inner borders have been swapped, as recommended by Graham Asher. * src/base/ftstroke.c: Revised. * include/freetype/ftstroke.h: Updated.
2011-07-02 12:09:52 +02:00
outline->n_points = (short)( outline->n_points + border->num_points );
FT_ASSERT( FT_Outline_Check( outline ) == 0 );
}
[ftstroke] Major revision. The main problems ----------------- o If FT_STROKER_LINEJOIN_BEVEL was specified, unlimited miter joins (not bevel joins) were generated. Indeed, the meanings of `miter' and `bevel' were incorrectly reversed (consistently) in both the code and comments. o The way bevel joins were constructed (whether specified explicitly, or created as a result of exceeding the miter limit) did not match what is required for stroked text in PostScript or PDF. The main fixes -------------- o The behaviour of FT_STROKER_LINEJOIN_BEVEL has been corrected. o A new line join style, FT_STROKER_LINEJOIN_MITER_FIXED, has been introduced to support PostScript and PDF miter joins. o FT_STROKER_LINEJOIN_MITER_VARIABLE has been introduced as an alias for FT_STROKER_LINEJOIN_MITER. Additionally, a variety of stroking errors have been fixed. These would cause various artifacts (including points `at infinity'), especially when stroking poor quality fonts. See http://lists.gnu.org/archive/html/freetype-devel/2011-07/msg00001.html for example documents. The FreeType stroker now produces results very similar to that produced by GhostScript and Distiller for these fonts. Other problems -------------- The following problems have been resolved: o Inside corners could be generated incorrectly. Intersecting the inside corner could cause a missing triangular area and other effects. The intersection point can only be used if the join is between two lines and both lines are long enough. The `optimization' condition in `ft_stroker_inside' has been corrected; this requires the line length to be passed into various functions and stored in `FT_StrokerRec'. o Incorrect cubic curves could be generated. The angle calculations in `FT_Stroker_CubicTo' have been corrected to handle the case of the curve crossing the +/-PI direction. o If the border radius was greater than the radius of curvature of a curve, then the negative sector would end up outside (not inside) the border. This situation is now recognized and the negative sector is circumnavigated in the opposite direction. (If round line joins are being used, this code is disabled because the line join will always cover the negative sector.) o When a curve is split, the arcs may not join smoothly (especially if the curve turns sharply back on itself). Changes in direction between adjacent arcs were not handled. A round corner is now added if the deviation from one arc to the next is greater than a suitable threshold. o The current direction wasn't retained if a the outline contained a zero length lineto or a curve that was determined to be `basically a point'. This could cause a spurious join to be added. o Cubics with close control points could be mishandled. All eight cases are now distinguished correctly. Other improvements ------------------ o Borders for cubic curves could be too `flat'. FT_SMALL_CUBIC_THRESHOLD has been reduced a little to prevent this. o The handling and use of movable points has been simplified a little. o Various values are now computed only if the results are actually needed. o The directions of the outer and inner borders have been swapped, as recommended by Graham Asher. * src/base/ftstroke.c: Revised. * include/freetype/ftstroke.h: Updated.
2011-07-02 12:09:52 +02:00
/*************************************************************************/
/*************************************************************************/
/***** *****/
/***** STROKER *****/
/***** *****/
/*************************************************************************/
/*************************************************************************/
#define FT_SIDE_TO_ROTATE( s ) ( FT_ANGLE_PI2 - (s) * FT_ANGLE_PI )
typedef struct FT_StrokerRec_
{
[ftstroke] Major revision. The main problems ----------------- o If FT_STROKER_LINEJOIN_BEVEL was specified, unlimited miter joins (not bevel joins) were generated. Indeed, the meanings of `miter' and `bevel' were incorrectly reversed (consistently) in both the code and comments. o The way bevel joins were constructed (whether specified explicitly, or created as a result of exceeding the miter limit) did not match what is required for stroked text in PostScript or PDF. The main fixes -------------- o The behaviour of FT_STROKER_LINEJOIN_BEVEL has been corrected. o A new line join style, FT_STROKER_LINEJOIN_MITER_FIXED, has been introduced to support PostScript and PDF miter joins. o FT_STROKER_LINEJOIN_MITER_VARIABLE has been introduced as an alias for FT_STROKER_LINEJOIN_MITER. Additionally, a variety of stroking errors have been fixed. These would cause various artifacts (including points `at infinity'), especially when stroking poor quality fonts. See http://lists.gnu.org/archive/html/freetype-devel/2011-07/msg00001.html for example documents. The FreeType stroker now produces results very similar to that produced by GhostScript and Distiller for these fonts. Other problems -------------- The following problems have been resolved: o Inside corners could be generated incorrectly. Intersecting the inside corner could cause a missing triangular area and other effects. The intersection point can only be used if the join is between two lines and both lines are long enough. The `optimization' condition in `ft_stroker_inside' has been corrected; this requires the line length to be passed into various functions and stored in `FT_StrokerRec'. o Incorrect cubic curves could be generated. The angle calculations in `FT_Stroker_CubicTo' have been corrected to handle the case of the curve crossing the +/-PI direction. o If the border radius was greater than the radius of curvature of a curve, then the negative sector would end up outside (not inside) the border. This situation is now recognized and the negative sector is circumnavigated in the opposite direction. (If round line joins are being used, this code is disabled because the line join will always cover the negative sector.) o When a curve is split, the arcs may not join smoothly (especially if the curve turns sharply back on itself). Changes in direction between adjacent arcs were not handled. A round corner is now added if the deviation from one arc to the next is greater than a suitable threshold. o The current direction wasn't retained if a the outline contained a zero length lineto or a curve that was determined to be `basically a point'. This could cause a spurious join to be added. o Cubics with close control points could be mishandled. All eight cases are now distinguished correctly. Other improvements ------------------ o Borders for cubic curves could be too `flat'. FT_SMALL_CUBIC_THRESHOLD has been reduced a little to prevent this. o The handling and use of movable points has been simplified a little. o Various values are now computed only if the results are actually needed. o The directions of the outer and inner borders have been swapped, as recommended by Graham Asher. * src/base/ftstroke.c: Revised. * include/freetype/ftstroke.h: Updated.
2011-07-02 12:09:52 +02:00
FT_Angle angle_in; /* direction into curr join */
FT_Angle angle_out; /* direction out of join */
FT_Vector center; /* current position */
FT_Fixed line_length; /* length of last lineto */
FT_Bool first_point; /* is this the start? */
FT_Bool subpath_open; /* is the subpath open? */
FT_Angle subpath_angle; /* subpath start direction */
FT_Vector subpath_start; /* subpath start position */
FT_Fixed subpath_line_length; /* subpath start lineto len */
FT_Bool handle_wide_strokes; /* use wide strokes logic? */
FT_Stroker_LineCap line_cap;
FT_Stroker_LineJoin line_join;
[ftstroke] Major revision. The main problems ----------------- o If FT_STROKER_LINEJOIN_BEVEL was specified, unlimited miter joins (not bevel joins) were generated. Indeed, the meanings of `miter' and `bevel' were incorrectly reversed (consistently) in both the code and comments. o The way bevel joins were constructed (whether specified explicitly, or created as a result of exceeding the miter limit) did not match what is required for stroked text in PostScript or PDF. The main fixes -------------- o The behaviour of FT_STROKER_LINEJOIN_BEVEL has been corrected. o A new line join style, FT_STROKER_LINEJOIN_MITER_FIXED, has been introduced to support PostScript and PDF miter joins. o FT_STROKER_LINEJOIN_MITER_VARIABLE has been introduced as an alias for FT_STROKER_LINEJOIN_MITER. Additionally, a variety of stroking errors have been fixed. These would cause various artifacts (including points `at infinity'), especially when stroking poor quality fonts. See http://lists.gnu.org/archive/html/freetype-devel/2011-07/msg00001.html for example documents. The FreeType stroker now produces results very similar to that produced by GhostScript and Distiller for these fonts. Other problems -------------- The following problems have been resolved: o Inside corners could be generated incorrectly. Intersecting the inside corner could cause a missing triangular area and other effects. The intersection point can only be used if the join is between two lines and both lines are long enough. The `optimization' condition in `ft_stroker_inside' has been corrected; this requires the line length to be passed into various functions and stored in `FT_StrokerRec'. o Incorrect cubic curves could be generated. The angle calculations in `FT_Stroker_CubicTo' have been corrected to handle the case of the curve crossing the +/-PI direction. o If the border radius was greater than the radius of curvature of a curve, then the negative sector would end up outside (not inside) the border. This situation is now recognized and the negative sector is circumnavigated in the opposite direction. (If round line joins are being used, this code is disabled because the line join will always cover the negative sector.) o When a curve is split, the arcs may not join smoothly (especially if the curve turns sharply back on itself). Changes in direction between adjacent arcs were not handled. A round corner is now added if the deviation from one arc to the next is greater than a suitable threshold. o The current direction wasn't retained if a the outline contained a zero length lineto or a curve that was determined to be `basically a point'. This could cause a spurious join to be added. o Cubics with close control points could be mishandled. All eight cases are now distinguished correctly. Other improvements ------------------ o Borders for cubic curves could be too `flat'. FT_SMALL_CUBIC_THRESHOLD has been reduced a little to prevent this. o The handling and use of movable points has been simplified a little. o Various values are now computed only if the results are actually needed. o The directions of the outer and inner borders have been swapped, as recommended by Graham Asher. * src/base/ftstroke.c: Revised. * include/freetype/ftstroke.h: Updated.
2011-07-02 12:09:52 +02:00
FT_Stroker_LineJoin line_join_saved;
FT_Fixed miter_limit;
FT_Fixed radius;
FT_StrokeBorderRec borders[2];
FT_Library library;
} FT_StrokerRec;
2004-12-14 00:16:59 +01:00
/* documentation is in ftstroke.h */
FT_EXPORT_DEF( FT_Error )
FT_Stroker_New( FT_Library library,
FT_Stroker *astroker )
{
2012-07-13 23:52:43 +02:00
FT_Error error; /* assigned in FT_NEW */
FT_Memory memory;
FT_Stroker stroker = NULL;
if ( !library )
return FT_THROW( Invalid_Argument );
memory = library->memory;
if ( !FT_NEW( stroker ) )
{
stroker->library = library;
ft_stroke_border_init( &stroker->borders[0], memory );
ft_stroke_border_init( &stroker->borders[1], memory );
}
[ftstroke] Major revision. The main problems ----------------- o If FT_STROKER_LINEJOIN_BEVEL was specified, unlimited miter joins (not bevel joins) were generated. Indeed, the meanings of `miter' and `bevel' were incorrectly reversed (consistently) in both the code and comments. o The way bevel joins were constructed (whether specified explicitly, or created as a result of exceeding the miter limit) did not match what is required for stroked text in PostScript or PDF. The main fixes -------------- o The behaviour of FT_STROKER_LINEJOIN_BEVEL has been corrected. o A new line join style, FT_STROKER_LINEJOIN_MITER_FIXED, has been introduced to support PostScript and PDF miter joins. o FT_STROKER_LINEJOIN_MITER_VARIABLE has been introduced as an alias for FT_STROKER_LINEJOIN_MITER. Additionally, a variety of stroking errors have been fixed. These would cause various artifacts (including points `at infinity'), especially when stroking poor quality fonts. See http://lists.gnu.org/archive/html/freetype-devel/2011-07/msg00001.html for example documents. The FreeType stroker now produces results very similar to that produced by GhostScript and Distiller for these fonts. Other problems -------------- The following problems have been resolved: o Inside corners could be generated incorrectly. Intersecting the inside corner could cause a missing triangular area and other effects. The intersection point can only be used if the join is between two lines and both lines are long enough. The `optimization' condition in `ft_stroker_inside' has been corrected; this requires the line length to be passed into various functions and stored in `FT_StrokerRec'. o Incorrect cubic curves could be generated. The angle calculations in `FT_Stroker_CubicTo' have been corrected to handle the case of the curve crossing the +/-PI direction. o If the border radius was greater than the radius of curvature of a curve, then the negative sector would end up outside (not inside) the border. This situation is now recognized and the negative sector is circumnavigated in the opposite direction. (If round line joins are being used, this code is disabled because the line join will always cover the negative sector.) o When a curve is split, the arcs may not join smoothly (especially if the curve turns sharply back on itself). Changes in direction between adjacent arcs were not handled. A round corner is now added if the deviation from one arc to the next is greater than a suitable threshold. o The current direction wasn't retained if a the outline contained a zero length lineto or a curve that was determined to be `basically a point'. This could cause a spurious join to be added. o Cubics with close control points could be mishandled. All eight cases are now distinguished correctly. Other improvements ------------------ o Borders for cubic curves could be too `flat'. FT_SMALL_CUBIC_THRESHOLD has been reduced a little to prevent this. o The handling and use of movable points has been simplified a little. o Various values are now computed only if the results are actually needed. o The directions of the outer and inner borders have been swapped, as recommended by Graham Asher. * src/base/ftstroke.c: Revised. * include/freetype/ftstroke.h: Updated.
2011-07-02 12:09:52 +02:00
*astroker = stroker;
[ftstroke] Major revision. The main problems ----------------- o If FT_STROKER_LINEJOIN_BEVEL was specified, unlimited miter joins (not bevel joins) were generated. Indeed, the meanings of `miter' and `bevel' were incorrectly reversed (consistently) in both the code and comments. o The way bevel joins were constructed (whether specified explicitly, or created as a result of exceeding the miter limit) did not match what is required for stroked text in PostScript or PDF. The main fixes -------------- o The behaviour of FT_STROKER_LINEJOIN_BEVEL has been corrected. o A new line join style, FT_STROKER_LINEJOIN_MITER_FIXED, has been introduced to support PostScript and PDF miter joins. o FT_STROKER_LINEJOIN_MITER_VARIABLE has been introduced as an alias for FT_STROKER_LINEJOIN_MITER. Additionally, a variety of stroking errors have been fixed. These would cause various artifacts (including points `at infinity'), especially when stroking poor quality fonts. See http://lists.gnu.org/archive/html/freetype-devel/2011-07/msg00001.html for example documents. The FreeType stroker now produces results very similar to that produced by GhostScript and Distiller for these fonts. Other problems -------------- The following problems have been resolved: o Inside corners could be generated incorrectly. Intersecting the inside corner could cause a missing triangular area and other effects. The intersection point can only be used if the join is between two lines and both lines are long enough. The `optimization' condition in `ft_stroker_inside' has been corrected; this requires the line length to be passed into various functions and stored in `FT_StrokerRec'. o Incorrect cubic curves could be generated. The angle calculations in `FT_Stroker_CubicTo' have been corrected to handle the case of the curve crossing the +/-PI direction. o If the border radius was greater than the radius of curvature of a curve, then the negative sector would end up outside (not inside) the border. This situation is now recognized and the negative sector is circumnavigated in the opposite direction. (If round line joins are being used, this code is disabled because the line join will always cover the negative sector.) o When a curve is split, the arcs may not join smoothly (especially if the curve turns sharply back on itself). Changes in direction between adjacent arcs were not handled. A round corner is now added if the deviation from one arc to the next is greater than a suitable threshold. o The current direction wasn't retained if a the outline contained a zero length lineto or a curve that was determined to be `basically a point'. This could cause a spurious join to be added. o Cubics with close control points could be mishandled. All eight cases are now distinguished correctly. Other improvements ------------------ o Borders for cubic curves could be too `flat'. FT_SMALL_CUBIC_THRESHOLD has been reduced a little to prevent this. o The handling and use of movable points has been simplified a little. o Various values are now computed only if the results are actually needed. o The directions of the outer and inner borders have been swapped, as recommended by Graham Asher. * src/base/ftstroke.c: Revised. * include/freetype/ftstroke.h: Updated.
2011-07-02 12:09:52 +02:00
2012-07-13 23:52:43 +02:00
return error;
}
2004-12-14 00:16:59 +01:00
/* documentation is in ftstroke.h */
FT_EXPORT_DEF( void )
FT_Stroker_Set( FT_Stroker stroker,
FT_Fixed radius,
FT_Stroker_LineCap line_cap,
FT_Stroker_LineJoin line_join,
FT_Fixed miter_limit )
{
stroker->radius = radius;
stroker->line_cap = line_cap;
stroker->line_join = line_join;
stroker->miter_limit = miter_limit;
[ftstroke] Major revision. The main problems ----------------- o If FT_STROKER_LINEJOIN_BEVEL was specified, unlimited miter joins (not bevel joins) were generated. Indeed, the meanings of `miter' and `bevel' were incorrectly reversed (consistently) in both the code and comments. o The way bevel joins were constructed (whether specified explicitly, or created as a result of exceeding the miter limit) did not match what is required for stroked text in PostScript or PDF. The main fixes -------------- o The behaviour of FT_STROKER_LINEJOIN_BEVEL has been corrected. o A new line join style, FT_STROKER_LINEJOIN_MITER_FIXED, has been introduced to support PostScript and PDF miter joins. o FT_STROKER_LINEJOIN_MITER_VARIABLE has been introduced as an alias for FT_STROKER_LINEJOIN_MITER. Additionally, a variety of stroking errors have been fixed. These would cause various artifacts (including points `at infinity'), especially when stroking poor quality fonts. See http://lists.gnu.org/archive/html/freetype-devel/2011-07/msg00001.html for example documents. The FreeType stroker now produces results very similar to that produced by GhostScript and Distiller for these fonts. Other problems -------------- The following problems have been resolved: o Inside corners could be generated incorrectly. Intersecting the inside corner could cause a missing triangular area and other effects. The intersection point can only be used if the join is between two lines and both lines are long enough. The `optimization' condition in `ft_stroker_inside' has been corrected; this requires the line length to be passed into various functions and stored in `FT_StrokerRec'. o Incorrect cubic curves could be generated. The angle calculations in `FT_Stroker_CubicTo' have been corrected to handle the case of the curve crossing the +/-PI direction. o If the border radius was greater than the radius of curvature of a curve, then the negative sector would end up outside (not inside) the border. This situation is now recognized and the negative sector is circumnavigated in the opposite direction. (If round line joins are being used, this code is disabled because the line join will always cover the negative sector.) o When a curve is split, the arcs may not join smoothly (especially if the curve turns sharply back on itself). Changes in direction between adjacent arcs were not handled. A round corner is now added if the deviation from one arc to the next is greater than a suitable threshold. o The current direction wasn't retained if a the outline contained a zero length lineto or a curve that was determined to be `basically a point'. This could cause a spurious join to be added. o Cubics with close control points could be mishandled. All eight cases are now distinguished correctly. Other improvements ------------------ o Borders for cubic curves could be too `flat'. FT_SMALL_CUBIC_THRESHOLD has been reduced a little to prevent this. o The handling and use of movable points has been simplified a little. o Various values are now computed only if the results are actually needed. o The directions of the outer and inner borders have been swapped, as recommended by Graham Asher. * src/base/ftstroke.c: Revised. * include/freetype/ftstroke.h: Updated.
2011-07-02 12:09:52 +02:00
/* ensure miter limit has sensible value */
if ( stroker->miter_limit < 0x10000 )
stroker->miter_limit = 0x10000;
/* save line join style: */
/* line join style can be temporarily changed when stroking curves */
stroker->line_join_saved = line_join;
FT_Stroker_Rewind( stroker );
}
2004-12-14 00:16:59 +01:00
/* documentation is in ftstroke.h */
FT_EXPORT_DEF( void )
FT_Stroker_Rewind( FT_Stroker stroker )
{
if ( stroker )
{
ft_stroke_border_reset( &stroker->borders[0] );
ft_stroke_border_reset( &stroker->borders[1] );
}
}
2004-12-14 00:16:59 +01:00
/* documentation is in ftstroke.h */
FT_EXPORT_DEF( void )
FT_Stroker_Done( FT_Stroker stroker )
{
if ( stroker )
{
FT_Memory memory = stroker->library->memory;
ft_stroke_border_done( &stroker->borders[0] );
ft_stroke_border_done( &stroker->borders[1] );
stroker->library = NULL;
FT_FREE( stroker );
}
}
[ftstroke] Major revision. The main problems ----------------- o If FT_STROKER_LINEJOIN_BEVEL was specified, unlimited miter joins (not bevel joins) were generated. Indeed, the meanings of `miter' and `bevel' were incorrectly reversed (consistently) in both the code and comments. o The way bevel joins were constructed (whether specified explicitly, or created as a result of exceeding the miter limit) did not match what is required for stroked text in PostScript or PDF. The main fixes -------------- o The behaviour of FT_STROKER_LINEJOIN_BEVEL has been corrected. o A new line join style, FT_STROKER_LINEJOIN_MITER_FIXED, has been introduced to support PostScript and PDF miter joins. o FT_STROKER_LINEJOIN_MITER_VARIABLE has been introduced as an alias for FT_STROKER_LINEJOIN_MITER. Additionally, a variety of stroking errors have been fixed. These would cause various artifacts (including points `at infinity'), especially when stroking poor quality fonts. See http://lists.gnu.org/archive/html/freetype-devel/2011-07/msg00001.html for example documents. The FreeType stroker now produces results very similar to that produced by GhostScript and Distiller for these fonts. Other problems -------------- The following problems have been resolved: o Inside corners could be generated incorrectly. Intersecting the inside corner could cause a missing triangular area and other effects. The intersection point can only be used if the join is between two lines and both lines are long enough. The `optimization' condition in `ft_stroker_inside' has been corrected; this requires the line length to be passed into various functions and stored in `FT_StrokerRec'. o Incorrect cubic curves could be generated. The angle calculations in `FT_Stroker_CubicTo' have been corrected to handle the case of the curve crossing the +/-PI direction. o If the border radius was greater than the radius of curvature of a curve, then the negative sector would end up outside (not inside) the border. This situation is now recognized and the negative sector is circumnavigated in the opposite direction. (If round line joins are being used, this code is disabled because the line join will always cover the negative sector.) o When a curve is split, the arcs may not join smoothly (especially if the curve turns sharply back on itself). Changes in direction between adjacent arcs were not handled. A round corner is now added if the deviation from one arc to the next is greater than a suitable threshold. o The current direction wasn't retained if a the outline contained a zero length lineto or a curve that was determined to be `basically a point'. This could cause a spurious join to be added. o Cubics with close control points could be mishandled. All eight cases are now distinguished correctly. Other improvements ------------------ o Borders for cubic curves could be too `flat'. FT_SMALL_CUBIC_THRESHOLD has been reduced a little to prevent this. o The handling and use of movable points has been simplified a little. o Various values are now computed only if the results are actually needed. o The directions of the outer and inner borders have been swapped, as recommended by Graham Asher. * src/base/ftstroke.c: Revised. * include/freetype/ftstroke.h: Updated.
2011-07-02 12:09:52 +02:00
/* create a circular arc at a corner or cap */
static FT_Error
ft_stroker_arcto( FT_Stroker stroker,
FT_Int side )
{
FT_Angle total, rotate;
FT_Fixed radius = stroker->radius;
2008-09-16 19:32:02 +02:00
FT_Error error = FT_Err_Ok;
FT_StrokeBorder border = stroker->borders + side;
rotate = FT_SIDE_TO_ROTATE( side );
total = FT_Angle_Diff( stroker->angle_in, stroker->angle_out );
if ( total == FT_ANGLE_PI )
total = -rotate * 2;
error = ft_stroke_border_arcto( border,
&stroker->center,
radius,
stroker->angle_in + rotate,
total );
2008-09-16 19:32:02 +02:00
border->movable = FALSE;
return error;
}
[ftstroke] Major revision. The main problems ----------------- o If FT_STROKER_LINEJOIN_BEVEL was specified, unlimited miter joins (not bevel joins) were generated. Indeed, the meanings of `miter' and `bevel' were incorrectly reversed (consistently) in both the code and comments. o The way bevel joins were constructed (whether specified explicitly, or created as a result of exceeding the miter limit) did not match what is required for stroked text in PostScript or PDF. The main fixes -------------- o The behaviour of FT_STROKER_LINEJOIN_BEVEL has been corrected. o A new line join style, FT_STROKER_LINEJOIN_MITER_FIXED, has been introduced to support PostScript and PDF miter joins. o FT_STROKER_LINEJOIN_MITER_VARIABLE has been introduced as an alias for FT_STROKER_LINEJOIN_MITER. Additionally, a variety of stroking errors have been fixed. These would cause various artifacts (including points `at infinity'), especially when stroking poor quality fonts. See http://lists.gnu.org/archive/html/freetype-devel/2011-07/msg00001.html for example documents. The FreeType stroker now produces results very similar to that produced by GhostScript and Distiller for these fonts. Other problems -------------- The following problems have been resolved: o Inside corners could be generated incorrectly. Intersecting the inside corner could cause a missing triangular area and other effects. The intersection point can only be used if the join is between two lines and both lines are long enough. The `optimization' condition in `ft_stroker_inside' has been corrected; this requires the line length to be passed into various functions and stored in `FT_StrokerRec'. o Incorrect cubic curves could be generated. The angle calculations in `FT_Stroker_CubicTo' have been corrected to handle the case of the curve crossing the +/-PI direction. o If the border radius was greater than the radius of curvature of a curve, then the negative sector would end up outside (not inside) the border. This situation is now recognized and the negative sector is circumnavigated in the opposite direction. (If round line joins are being used, this code is disabled because the line join will always cover the negative sector.) o When a curve is split, the arcs may not join smoothly (especially if the curve turns sharply back on itself). Changes in direction between adjacent arcs were not handled. A round corner is now added if the deviation from one arc to the next is greater than a suitable threshold. o The current direction wasn't retained if a the outline contained a zero length lineto or a curve that was determined to be `basically a point'. This could cause a spurious join to be added. o Cubics with close control points could be mishandled. All eight cases are now distinguished correctly. Other improvements ------------------ o Borders for cubic curves could be too `flat'. FT_SMALL_CUBIC_THRESHOLD has been reduced a little to prevent this. o The handling and use of movable points has been simplified a little. o Various values are now computed only if the results are actually needed. o The directions of the outer and inner borders have been swapped, as recommended by Graham Asher. * src/base/ftstroke.c: Revised. * include/freetype/ftstroke.h: Updated.
2011-07-02 12:09:52 +02:00
/* add a cap at the end of an opened path */
static FT_Error
ft_stroker_cap( FT_Stroker stroker,
FT_Angle angle,
FT_Int side )
{
2008-09-16 19:32:02 +02:00
FT_Error error = FT_Err_Ok;
if ( stroker->line_cap == FT_STROKER_LINECAP_ROUND )
{
/* add a round cap */
stroker->angle_in = angle;
stroker->angle_out = angle + FT_ANGLE_PI;
[ftstroke] Major revision. The main problems ----------------- o If FT_STROKER_LINEJOIN_BEVEL was specified, unlimited miter joins (not bevel joins) were generated. Indeed, the meanings of `miter' and `bevel' were incorrectly reversed (consistently) in both the code and comments. o The way bevel joins were constructed (whether specified explicitly, or created as a result of exceeding the miter limit) did not match what is required for stroked text in PostScript or PDF. The main fixes -------------- o The behaviour of FT_STROKER_LINEJOIN_BEVEL has been corrected. o A new line join style, FT_STROKER_LINEJOIN_MITER_FIXED, has been introduced to support PostScript and PDF miter joins. o FT_STROKER_LINEJOIN_MITER_VARIABLE has been introduced as an alias for FT_STROKER_LINEJOIN_MITER. Additionally, a variety of stroking errors have been fixed. These would cause various artifacts (including points `at infinity'), especially when stroking poor quality fonts. See http://lists.gnu.org/archive/html/freetype-devel/2011-07/msg00001.html for example documents. The FreeType stroker now produces results very similar to that produced by GhostScript and Distiller for these fonts. Other problems -------------- The following problems have been resolved: o Inside corners could be generated incorrectly. Intersecting the inside corner could cause a missing triangular area and other effects. The intersection point can only be used if the join is between two lines and both lines are long enough. The `optimization' condition in `ft_stroker_inside' has been corrected; this requires the line length to be passed into various functions and stored in `FT_StrokerRec'. o Incorrect cubic curves could be generated. The angle calculations in `FT_Stroker_CubicTo' have been corrected to handle the case of the curve crossing the +/-PI direction. o If the border radius was greater than the radius of curvature of a curve, then the negative sector would end up outside (not inside) the border. This situation is now recognized and the negative sector is circumnavigated in the opposite direction. (If round line joins are being used, this code is disabled because the line join will always cover the negative sector.) o When a curve is split, the arcs may not join smoothly (especially if the curve turns sharply back on itself). Changes in direction between adjacent arcs were not handled. A round corner is now added if the deviation from one arc to the next is greater than a suitable threshold. o The current direction wasn't retained if a the outline contained a zero length lineto or a curve that was determined to be `basically a point'. This could cause a spurious join to be added. o Cubics with close control points could be mishandled. All eight cases are now distinguished correctly. Other improvements ------------------ o Borders for cubic curves could be too `flat'. FT_SMALL_CUBIC_THRESHOLD has been reduced a little to prevent this. o The handling and use of movable points has been simplified a little. o Various values are now computed only if the results are actually needed. o The directions of the outer and inner borders have been swapped, as recommended by Graham Asher. * src/base/ftstroke.c: Revised. * include/freetype/ftstroke.h: Updated.
2011-07-02 12:09:52 +02:00
error = ft_stroker_arcto( stroker, side );
}
else if ( stroker->line_cap == FT_STROKER_LINECAP_SQUARE )
{
/* add a square cap */
FT_Vector delta, delta2;
FT_Angle rotate = FT_SIDE_TO_ROTATE( side );
FT_Fixed radius = stroker->radius;
FT_StrokeBorder border = stroker->borders + side;
FT_Vector_From_Polar( &delta2, radius, angle + rotate );
FT_Vector_From_Polar( &delta, radius, angle );
delta.x += stroker->center.x + delta2.x;
delta.y += stroker->center.y + delta2.y;
2008-09-16 19:32:02 +02:00
error = ft_stroke_border_lineto( border, &delta, FALSE );
if ( error )
goto Exit;
FT_Vector_From_Polar( &delta2, radius, angle - rotate );
FT_Vector_From_Polar( &delta, radius, angle );
delta.x += delta2.x + stroker->center.x;
delta.y += delta2.y + stroker->center.y;
2008-09-16 19:32:02 +02:00
error = ft_stroke_border_lineto( border, &delta, FALSE );
}
else if ( stroker->line_cap == FT_STROKER_LINECAP_BUTT )
{
/* add a butt ending */
FT_Vector delta;
FT_Angle rotate = FT_SIDE_TO_ROTATE( side );
FT_Fixed radius = stroker->radius;
FT_StrokeBorder border = stroker->borders + side;
FT_Vector_From_Polar( &delta, radius, angle + rotate );
delta.x += stroker->center.x;
delta.y += stroker->center.y;
error = ft_stroke_border_lineto( border, &delta, FALSE );
if ( error )
goto Exit;
FT_Vector_From_Polar( &delta, radius, angle - rotate );
delta.x += stroker->center.x;
delta.y += stroker->center.y;
[ftstroke] Major revision. The main problems ----------------- o If FT_STROKER_LINEJOIN_BEVEL was specified, unlimited miter joins (not bevel joins) were generated. Indeed, the meanings of `miter' and `bevel' were incorrectly reversed (consistently) in both the code and comments. o The way bevel joins were constructed (whether specified explicitly, or created as a result of exceeding the miter limit) did not match what is required for stroked text in PostScript or PDF. The main fixes -------------- o The behaviour of FT_STROKER_LINEJOIN_BEVEL has been corrected. o A new line join style, FT_STROKER_LINEJOIN_MITER_FIXED, has been introduced to support PostScript and PDF miter joins. o FT_STROKER_LINEJOIN_MITER_VARIABLE has been introduced as an alias for FT_STROKER_LINEJOIN_MITER. Additionally, a variety of stroking errors have been fixed. These would cause various artifacts (including points `at infinity'), especially when stroking poor quality fonts. See http://lists.gnu.org/archive/html/freetype-devel/2011-07/msg00001.html for example documents. The FreeType stroker now produces results very similar to that produced by GhostScript and Distiller for these fonts. Other problems -------------- The following problems have been resolved: o Inside corners could be generated incorrectly. Intersecting the inside corner could cause a missing triangular area and other effects. The intersection point can only be used if the join is between two lines and both lines are long enough. The `optimization' condition in `ft_stroker_inside' has been corrected; this requires the line length to be passed into various functions and stored in `FT_StrokerRec'. o Incorrect cubic curves could be generated. The angle calculations in `FT_Stroker_CubicTo' have been corrected to handle the case of the curve crossing the +/-PI direction. o If the border radius was greater than the radius of curvature of a curve, then the negative sector would end up outside (not inside) the border. This situation is now recognized and the negative sector is circumnavigated in the opposite direction. (If round line joins are being used, this code is disabled because the line join will always cover the negative sector.) o When a curve is split, the arcs may not join smoothly (especially if the curve turns sharply back on itself). Changes in direction between adjacent arcs were not handled. A round corner is now added if the deviation from one arc to the next is greater than a suitable threshold. o The current direction wasn't retained if a the outline contained a zero length lineto or a curve that was determined to be `basically a point'. This could cause a spurious join to be added. o Cubics with close control points could be mishandled. All eight cases are now distinguished correctly. Other improvements ------------------ o Borders for cubic curves could be too `flat'. FT_SMALL_CUBIC_THRESHOLD has been reduced a little to prevent this. o The handling and use of movable points has been simplified a little. o Various values are now computed only if the results are actually needed. o The directions of the outer and inner borders have been swapped, as recommended by Graham Asher. * src/base/ftstroke.c: Revised. * include/freetype/ftstroke.h: Updated.
2011-07-02 12:09:52 +02:00
error = ft_stroke_border_lineto( border, &delta, FALSE );
}
Exit:
return error;
}
/* process an inside corner, i.e. compute intersection */
static FT_Error
ft_stroker_inside( FT_Stroker stroker,
[ftstroke] Major revision. The main problems ----------------- o If FT_STROKER_LINEJOIN_BEVEL was specified, unlimited miter joins (not bevel joins) were generated. Indeed, the meanings of `miter' and `bevel' were incorrectly reversed (consistently) in both the code and comments. o The way bevel joins were constructed (whether specified explicitly, or created as a result of exceeding the miter limit) did not match what is required for stroked text in PostScript or PDF. The main fixes -------------- o The behaviour of FT_STROKER_LINEJOIN_BEVEL has been corrected. o A new line join style, FT_STROKER_LINEJOIN_MITER_FIXED, has been introduced to support PostScript and PDF miter joins. o FT_STROKER_LINEJOIN_MITER_VARIABLE has been introduced as an alias for FT_STROKER_LINEJOIN_MITER. Additionally, a variety of stroking errors have been fixed. These would cause various artifacts (including points `at infinity'), especially when stroking poor quality fonts. See http://lists.gnu.org/archive/html/freetype-devel/2011-07/msg00001.html for example documents. The FreeType stroker now produces results very similar to that produced by GhostScript and Distiller for these fonts. Other problems -------------- The following problems have been resolved: o Inside corners could be generated incorrectly. Intersecting the inside corner could cause a missing triangular area and other effects. The intersection point can only be used if the join is between two lines and both lines are long enough. The `optimization' condition in `ft_stroker_inside' has been corrected; this requires the line length to be passed into various functions and stored in `FT_StrokerRec'. o Incorrect cubic curves could be generated. The angle calculations in `FT_Stroker_CubicTo' have been corrected to handle the case of the curve crossing the +/-PI direction. o If the border radius was greater than the radius of curvature of a curve, then the negative sector would end up outside (not inside) the border. This situation is now recognized and the negative sector is circumnavigated in the opposite direction. (If round line joins are being used, this code is disabled because the line join will always cover the negative sector.) o When a curve is split, the arcs may not join smoothly (especially if the curve turns sharply back on itself). Changes in direction between adjacent arcs were not handled. A round corner is now added if the deviation from one arc to the next is greater than a suitable threshold. o The current direction wasn't retained if a the outline contained a zero length lineto or a curve that was determined to be `basically a point'. This could cause a spurious join to be added. o Cubics with close control points could be mishandled. All eight cases are now distinguished correctly. Other improvements ------------------ o Borders for cubic curves could be too `flat'. FT_SMALL_CUBIC_THRESHOLD has been reduced a little to prevent this. o The handling and use of movable points has been simplified a little. o Various values are now computed only if the results are actually needed. o The directions of the outer and inner borders have been swapped, as recommended by Graham Asher. * src/base/ftstroke.c: Revised. * include/freetype/ftstroke.h: Updated.
2011-07-02 12:09:52 +02:00
FT_Int side,
FT_Fixed line_length )
{
FT_StrokeBorder border = stroker->borders + side;
FT_Angle phi, theta, rotate;
[ftstroke] Major revision. The main problems ----------------- o If FT_STROKER_LINEJOIN_BEVEL was specified, unlimited miter joins (not bevel joins) were generated. Indeed, the meanings of `miter' and `bevel' were incorrectly reversed (consistently) in both the code and comments. o The way bevel joins were constructed (whether specified explicitly, or created as a result of exceeding the miter limit) did not match what is required for stroked text in PostScript or PDF. The main fixes -------------- o The behaviour of FT_STROKER_LINEJOIN_BEVEL has been corrected. o A new line join style, FT_STROKER_LINEJOIN_MITER_FIXED, has been introduced to support PostScript and PDF miter joins. o FT_STROKER_LINEJOIN_MITER_VARIABLE has been introduced as an alias for FT_STROKER_LINEJOIN_MITER. Additionally, a variety of stroking errors have been fixed. These would cause various artifacts (including points `at infinity'), especially when stroking poor quality fonts. See http://lists.gnu.org/archive/html/freetype-devel/2011-07/msg00001.html for example documents. The FreeType stroker now produces results very similar to that produced by GhostScript and Distiller for these fonts. Other problems -------------- The following problems have been resolved: o Inside corners could be generated incorrectly. Intersecting the inside corner could cause a missing triangular area and other effects. The intersection point can only be used if the join is between two lines and both lines are long enough. The `optimization' condition in `ft_stroker_inside' has been corrected; this requires the line length to be passed into various functions and stored in `FT_StrokerRec'. o Incorrect cubic curves could be generated. The angle calculations in `FT_Stroker_CubicTo' have been corrected to handle the case of the curve crossing the +/-PI direction. o If the border radius was greater than the radius of curvature of a curve, then the negative sector would end up outside (not inside) the border. This situation is now recognized and the negative sector is circumnavigated in the opposite direction. (If round line joins are being used, this code is disabled because the line join will always cover the negative sector.) o When a curve is split, the arcs may not join smoothly (especially if the curve turns sharply back on itself). Changes in direction between adjacent arcs were not handled. A round corner is now added if the deviation from one arc to the next is greater than a suitable threshold. o The current direction wasn't retained if a the outline contained a zero length lineto or a curve that was determined to be `basically a point'. This could cause a spurious join to be added. o Cubics with close control points could be mishandled. All eight cases are now distinguished correctly. Other improvements ------------------ o Borders for cubic curves could be too `flat'. FT_SMALL_CUBIC_THRESHOLD has been reduced a little to prevent this. o The handling and use of movable points has been simplified a little. o Various values are now computed only if the results are actually needed. o The directions of the outer and inner borders have been swapped, as recommended by Graham Asher. * src/base/ftstroke.c: Revised. * include/freetype/ftstroke.h: Updated.
2011-07-02 12:09:52 +02:00
FT_Fixed length, thcos;
FT_Vector delta;
2008-09-16 19:32:02 +02:00
FT_Error error = FT_Err_Ok;
[ftstroke] Major revision. The main problems ----------------- o If FT_STROKER_LINEJOIN_BEVEL was specified, unlimited miter joins (not bevel joins) were generated. Indeed, the meanings of `miter' and `bevel' were incorrectly reversed (consistently) in both the code and comments. o The way bevel joins were constructed (whether specified explicitly, or created as a result of exceeding the miter limit) did not match what is required for stroked text in PostScript or PDF. The main fixes -------------- o The behaviour of FT_STROKER_LINEJOIN_BEVEL has been corrected. o A new line join style, FT_STROKER_LINEJOIN_MITER_FIXED, has been introduced to support PostScript and PDF miter joins. o FT_STROKER_LINEJOIN_MITER_VARIABLE has been introduced as an alias for FT_STROKER_LINEJOIN_MITER. Additionally, a variety of stroking errors have been fixed. These would cause various artifacts (including points `at infinity'), especially when stroking poor quality fonts. See http://lists.gnu.org/archive/html/freetype-devel/2011-07/msg00001.html for example documents. The FreeType stroker now produces results very similar to that produced by GhostScript and Distiller for these fonts. Other problems -------------- The following problems have been resolved: o Inside corners could be generated incorrectly. Intersecting the inside corner could cause a missing triangular area and other effects. The intersection point can only be used if the join is between two lines and both lines are long enough. The `optimization' condition in `ft_stroker_inside' has been corrected; this requires the line length to be passed into various functions and stored in `FT_StrokerRec'. o Incorrect cubic curves could be generated. The angle calculations in `FT_Stroker_CubicTo' have been corrected to handle the case of the curve crossing the +/-PI direction. o If the border radius was greater than the radius of curvature of a curve, then the negative sector would end up outside (not inside) the border. This situation is now recognized and the negative sector is circumnavigated in the opposite direction. (If round line joins are being used, this code is disabled because the line join will always cover the negative sector.) o When a curve is split, the arcs may not join smoothly (especially if the curve turns sharply back on itself). Changes in direction between adjacent arcs were not handled. A round corner is now added if the deviation from one arc to the next is greater than a suitable threshold. o The current direction wasn't retained if a the outline contained a zero length lineto or a curve that was determined to be `basically a point'. This could cause a spurious join to be added. o Cubics with close control points could be mishandled. All eight cases are now distinguished correctly. Other improvements ------------------ o Borders for cubic curves could be too `flat'. FT_SMALL_CUBIC_THRESHOLD has been reduced a little to prevent this. o The handling and use of movable points has been simplified a little. o Various values are now computed only if the results are actually needed. o The directions of the outer and inner borders have been swapped, as recommended by Graham Asher. * src/base/ftstroke.c: Revised. * include/freetype/ftstroke.h: Updated.
2011-07-02 12:09:52 +02:00
FT_Bool intersect; /* use intersection of lines? */
rotate = FT_SIDE_TO_ROTATE( side );
[ftstroke] Major revision. The main problems ----------------- o If FT_STROKER_LINEJOIN_BEVEL was specified, unlimited miter joins (not bevel joins) were generated. Indeed, the meanings of `miter' and `bevel' were incorrectly reversed (consistently) in both the code and comments. o The way bevel joins were constructed (whether specified explicitly, or created as a result of exceeding the miter limit) did not match what is required for stroked text in PostScript or PDF. The main fixes -------------- o The behaviour of FT_STROKER_LINEJOIN_BEVEL has been corrected. o A new line join style, FT_STROKER_LINEJOIN_MITER_FIXED, has been introduced to support PostScript and PDF miter joins. o FT_STROKER_LINEJOIN_MITER_VARIABLE has been introduced as an alias for FT_STROKER_LINEJOIN_MITER. Additionally, a variety of stroking errors have been fixed. These would cause various artifacts (including points `at infinity'), especially when stroking poor quality fonts. See http://lists.gnu.org/archive/html/freetype-devel/2011-07/msg00001.html for example documents. The FreeType stroker now produces results very similar to that produced by GhostScript and Distiller for these fonts. Other problems -------------- The following problems have been resolved: o Inside corners could be generated incorrectly. Intersecting the inside corner could cause a missing triangular area and other effects. The intersection point can only be used if the join is between two lines and both lines are long enough. The `optimization' condition in `ft_stroker_inside' has been corrected; this requires the line length to be passed into various functions and stored in `FT_StrokerRec'. o Incorrect cubic curves could be generated. The angle calculations in `FT_Stroker_CubicTo' have been corrected to handle the case of the curve crossing the +/-PI direction. o If the border radius was greater than the radius of curvature of a curve, then the negative sector would end up outside (not inside) the border. This situation is now recognized and the negative sector is circumnavigated in the opposite direction. (If round line joins are being used, this code is disabled because the line join will always cover the negative sector.) o When a curve is split, the arcs may not join smoothly (especially if the curve turns sharply back on itself). Changes in direction between adjacent arcs were not handled. A round corner is now added if the deviation from one arc to the next is greater than a suitable threshold. o The current direction wasn't retained if a the outline contained a zero length lineto or a curve that was determined to be `basically a point'. This could cause a spurious join to be added. o Cubics with close control points could be mishandled. All eight cases are now distinguished correctly. Other improvements ------------------ o Borders for cubic curves could be too `flat'. FT_SMALL_CUBIC_THRESHOLD has been reduced a little to prevent this. o The handling and use of movable points has been simplified a little. o Various values are now computed only if the results are actually needed. o The directions of the outer and inner borders have been swapped, as recommended by Graham Asher. * src/base/ftstroke.c: Revised. * include/freetype/ftstroke.h: Updated.
2011-07-02 12:09:52 +02:00
theta = FT_Angle_Diff( stroker->angle_in, stroker->angle_out ) / 2;
/* Only intersect borders if between two lineto's and both */
/* lines are long enough (line_length is zero for curves). */
if ( !border->movable || line_length == 0 )
intersect = FALSE;
else
[ftstroke] Major revision. The main problems ----------------- o If FT_STROKER_LINEJOIN_BEVEL was specified, unlimited miter joins (not bevel joins) were generated. Indeed, the meanings of `miter' and `bevel' were incorrectly reversed (consistently) in both the code and comments. o The way bevel joins were constructed (whether specified explicitly, or created as a result of exceeding the miter limit) did not match what is required for stroked text in PostScript or PDF. The main fixes -------------- o The behaviour of FT_STROKER_LINEJOIN_BEVEL has been corrected. o A new line join style, FT_STROKER_LINEJOIN_MITER_FIXED, has been introduced to support PostScript and PDF miter joins. o FT_STROKER_LINEJOIN_MITER_VARIABLE has been introduced as an alias for FT_STROKER_LINEJOIN_MITER. Additionally, a variety of stroking errors have been fixed. These would cause various artifacts (including points `at infinity'), especially when stroking poor quality fonts. See http://lists.gnu.org/archive/html/freetype-devel/2011-07/msg00001.html for example documents. The FreeType stroker now produces results very similar to that produced by GhostScript and Distiller for these fonts. Other problems -------------- The following problems have been resolved: o Inside corners could be generated incorrectly. Intersecting the inside corner could cause a missing triangular area and other effects. The intersection point can only be used if the join is between two lines and both lines are long enough. The `optimization' condition in `ft_stroker_inside' has been corrected; this requires the line length to be passed into various functions and stored in `FT_StrokerRec'. o Incorrect cubic curves could be generated. The angle calculations in `FT_Stroker_CubicTo' have been corrected to handle the case of the curve crossing the +/-PI direction. o If the border radius was greater than the radius of curvature of a curve, then the negative sector would end up outside (not inside) the border. This situation is now recognized and the negative sector is circumnavigated in the opposite direction. (If round line joins are being used, this code is disabled because the line join will always cover the negative sector.) o When a curve is split, the arcs may not join smoothly (especially if the curve turns sharply back on itself). Changes in direction between adjacent arcs were not handled. A round corner is now added if the deviation from one arc to the next is greater than a suitable threshold. o The current direction wasn't retained if a the outline contained a zero length lineto or a curve that was determined to be `basically a point'. This could cause a spurious join to be added. o Cubics with close control points could be mishandled. All eight cases are now distinguished correctly. Other improvements ------------------ o Borders for cubic curves could be too `flat'. FT_SMALL_CUBIC_THRESHOLD has been reduced a little to prevent this. o The handling and use of movable points has been simplified a little. o Various values are now computed only if the results are actually needed. o The directions of the outer and inner borders have been swapped, as recommended by Graham Asher. * src/base/ftstroke.c: Revised. * include/freetype/ftstroke.h: Updated.
2011-07-02 12:09:52 +02:00
{
/* compute minimum required length of lines */
FT_Fixed min_length = ft_pos_abs( FT_MulFix( stroker->radius,
FT_Tan( theta ) ) );
intersect = FT_BOOL( min_length &&
stroker->line_length >= min_length &&
[ftstroke] Major revision. The main problems ----------------- o If FT_STROKER_LINEJOIN_BEVEL was specified, unlimited miter joins (not bevel joins) were generated. Indeed, the meanings of `miter' and `bevel' were incorrectly reversed (consistently) in both the code and comments. o The way bevel joins were constructed (whether specified explicitly, or created as a result of exceeding the miter limit) did not match what is required for stroked text in PostScript or PDF. The main fixes -------------- o The behaviour of FT_STROKER_LINEJOIN_BEVEL has been corrected. o A new line join style, FT_STROKER_LINEJOIN_MITER_FIXED, has been introduced to support PostScript and PDF miter joins. o FT_STROKER_LINEJOIN_MITER_VARIABLE has been introduced as an alias for FT_STROKER_LINEJOIN_MITER. Additionally, a variety of stroking errors have been fixed. These would cause various artifacts (including points `at infinity'), especially when stroking poor quality fonts. See http://lists.gnu.org/archive/html/freetype-devel/2011-07/msg00001.html for example documents. The FreeType stroker now produces results very similar to that produced by GhostScript and Distiller for these fonts. Other problems -------------- The following problems have been resolved: o Inside corners could be generated incorrectly. Intersecting the inside corner could cause a missing triangular area and other effects. The intersection point can only be used if the join is between two lines and both lines are long enough. The `optimization' condition in `ft_stroker_inside' has been corrected; this requires the line length to be passed into various functions and stored in `FT_StrokerRec'. o Incorrect cubic curves could be generated. The angle calculations in `FT_Stroker_CubicTo' have been corrected to handle the case of the curve crossing the +/-PI direction. o If the border radius was greater than the radius of curvature of a curve, then the negative sector would end up outside (not inside) the border. This situation is now recognized and the negative sector is circumnavigated in the opposite direction. (If round line joins are being used, this code is disabled because the line join will always cover the negative sector.) o When a curve is split, the arcs may not join smoothly (especially if the curve turns sharply back on itself). Changes in direction between adjacent arcs were not handled. A round corner is now added if the deviation from one arc to the next is greater than a suitable threshold. o The current direction wasn't retained if a the outline contained a zero length lineto or a curve that was determined to be `basically a point'. This could cause a spurious join to be added. o Cubics with close control points could be mishandled. All eight cases are now distinguished correctly. Other improvements ------------------ o Borders for cubic curves could be too `flat'. FT_SMALL_CUBIC_THRESHOLD has been reduced a little to prevent this. o The handling and use of movable points has been simplified a little. o Various values are now computed only if the results are actually needed. o The directions of the outer and inner borders have been swapped, as recommended by Graham Asher. * src/base/ftstroke.c: Revised. * include/freetype/ftstroke.h: Updated.
2011-07-02 12:09:52 +02:00
line_length >= min_length );
}
[ftstroke] Major revision. The main problems ----------------- o If FT_STROKER_LINEJOIN_BEVEL was specified, unlimited miter joins (not bevel joins) were generated. Indeed, the meanings of `miter' and `bevel' were incorrectly reversed (consistently) in both the code and comments. o The way bevel joins were constructed (whether specified explicitly, or created as a result of exceeding the miter limit) did not match what is required for stroked text in PostScript or PDF. The main fixes -------------- o The behaviour of FT_STROKER_LINEJOIN_BEVEL has been corrected. o A new line join style, FT_STROKER_LINEJOIN_MITER_FIXED, has been introduced to support PostScript and PDF miter joins. o FT_STROKER_LINEJOIN_MITER_VARIABLE has been introduced as an alias for FT_STROKER_LINEJOIN_MITER. Additionally, a variety of stroking errors have been fixed. These would cause various artifacts (including points `at infinity'), especially when stroking poor quality fonts. See http://lists.gnu.org/archive/html/freetype-devel/2011-07/msg00001.html for example documents. The FreeType stroker now produces results very similar to that produced by GhostScript and Distiller for these fonts. Other problems -------------- The following problems have been resolved: o Inside corners could be generated incorrectly. Intersecting the inside corner could cause a missing triangular area and other effects. The intersection point can only be used if the join is between two lines and both lines are long enough. The `optimization' condition in `ft_stroker_inside' has been corrected; this requires the line length to be passed into various functions and stored in `FT_StrokerRec'. o Incorrect cubic curves could be generated. The angle calculations in `FT_Stroker_CubicTo' have been corrected to handle the case of the curve crossing the +/-PI direction. o If the border radius was greater than the radius of curvature of a curve, then the negative sector would end up outside (not inside) the border. This situation is now recognized and the negative sector is circumnavigated in the opposite direction. (If round line joins are being used, this code is disabled because the line join will always cover the negative sector.) o When a curve is split, the arcs may not join smoothly (especially if the curve turns sharply back on itself). Changes in direction between adjacent arcs were not handled. A round corner is now added if the deviation from one arc to the next is greater than a suitable threshold. o The current direction wasn't retained if a the outline contained a zero length lineto or a curve that was determined to be `basically a point'. This could cause a spurious join to be added. o Cubics with close control points could be mishandled. All eight cases are now distinguished correctly. Other improvements ------------------ o Borders for cubic curves could be too `flat'. FT_SMALL_CUBIC_THRESHOLD has been reduced a little to prevent this. o The handling and use of movable points has been simplified a little. o Various values are now computed only if the results are actually needed. o The directions of the outer and inner borders have been swapped, as recommended by Graham Asher. * src/base/ftstroke.c: Revised. * include/freetype/ftstroke.h: Updated.
2011-07-02 12:09:52 +02:00
if ( !intersect )
{
FT_Vector_From_Polar( &delta, stroker->radius,
stroker->angle_out + rotate );
delta.x += stroker->center.x;
delta.y += stroker->center.y;
[ftstroke] Major revision. The main problems ----------------- o If FT_STROKER_LINEJOIN_BEVEL was specified, unlimited miter joins (not bevel joins) were generated. Indeed, the meanings of `miter' and `bevel' were incorrectly reversed (consistently) in both the code and comments. o The way bevel joins were constructed (whether specified explicitly, or created as a result of exceeding the miter limit) did not match what is required for stroked text in PostScript or PDF. The main fixes -------------- o The behaviour of FT_STROKER_LINEJOIN_BEVEL has been corrected. o A new line join style, FT_STROKER_LINEJOIN_MITER_FIXED, has been introduced to support PostScript and PDF miter joins. o FT_STROKER_LINEJOIN_MITER_VARIABLE has been introduced as an alias for FT_STROKER_LINEJOIN_MITER. Additionally, a variety of stroking errors have been fixed. These would cause various artifacts (including points `at infinity'), especially when stroking poor quality fonts. See http://lists.gnu.org/archive/html/freetype-devel/2011-07/msg00001.html for example documents. The FreeType stroker now produces results very similar to that produced by GhostScript and Distiller for these fonts. Other problems -------------- The following problems have been resolved: o Inside corners could be generated incorrectly. Intersecting the inside corner could cause a missing triangular area and other effects. The intersection point can only be used if the join is between two lines and both lines are long enough. The `optimization' condition in `ft_stroker_inside' has been corrected; this requires the line length to be passed into various functions and stored in `FT_StrokerRec'. o Incorrect cubic curves could be generated. The angle calculations in `FT_Stroker_CubicTo' have been corrected to handle the case of the curve crossing the +/-PI direction. o If the border radius was greater than the radius of curvature of a curve, then the negative sector would end up outside (not inside) the border. This situation is now recognized and the negative sector is circumnavigated in the opposite direction. (If round line joins are being used, this code is disabled because the line join will always cover the negative sector.) o When a curve is split, the arcs may not join smoothly (especially if the curve turns sharply back on itself). Changes in direction between adjacent arcs were not handled. A round corner is now added if the deviation from one arc to the next is greater than a suitable threshold. o The current direction wasn't retained if a the outline contained a zero length lineto or a curve that was determined to be `basically a point'. This could cause a spurious join to be added. o Cubics with close control points could be mishandled. All eight cases are now distinguished correctly. Other improvements ------------------ o Borders for cubic curves could be too `flat'. FT_SMALL_CUBIC_THRESHOLD has been reduced a little to prevent this. o The handling and use of movable points has been simplified a little. o Various values are now computed only if the results are actually needed. o The directions of the outer and inner borders have been swapped, as recommended by Graham Asher. * src/base/ftstroke.c: Revised. * include/freetype/ftstroke.h: Updated.
2011-07-02 12:09:52 +02:00
2008-09-16 19:32:02 +02:00
border->movable = FALSE;
}
else
{
[ftstroke] Major revision. The main problems ----------------- o If FT_STROKER_LINEJOIN_BEVEL was specified, unlimited miter joins (not bevel joins) were generated. Indeed, the meanings of `miter' and `bevel' were incorrectly reversed (consistently) in both the code and comments. o The way bevel joins were constructed (whether specified explicitly, or created as a result of exceeding the miter limit) did not match what is required for stroked text in PostScript or PDF. The main fixes -------------- o The behaviour of FT_STROKER_LINEJOIN_BEVEL has been corrected. o A new line join style, FT_STROKER_LINEJOIN_MITER_FIXED, has been introduced to support PostScript and PDF miter joins. o FT_STROKER_LINEJOIN_MITER_VARIABLE has been introduced as an alias for FT_STROKER_LINEJOIN_MITER. Additionally, a variety of stroking errors have been fixed. These would cause various artifacts (including points `at infinity'), especially when stroking poor quality fonts. See http://lists.gnu.org/archive/html/freetype-devel/2011-07/msg00001.html for example documents. The FreeType stroker now produces results very similar to that produced by GhostScript and Distiller for these fonts. Other problems -------------- The following problems have been resolved: o Inside corners could be generated incorrectly. Intersecting the inside corner could cause a missing triangular area and other effects. The intersection point can only be used if the join is between two lines and both lines are long enough. The `optimization' condition in `ft_stroker_inside' has been corrected; this requires the line length to be passed into various functions and stored in `FT_StrokerRec'. o Incorrect cubic curves could be generated. The angle calculations in `FT_Stroker_CubicTo' have been corrected to handle the case of the curve crossing the +/-PI direction. o If the border radius was greater than the radius of curvature of a curve, then the negative sector would end up outside (not inside) the border. This situation is now recognized and the negative sector is circumnavigated in the opposite direction. (If round line joins are being used, this code is disabled because the line join will always cover the negative sector.) o When a curve is split, the arcs may not join smoothly (especially if the curve turns sharply back on itself). Changes in direction between adjacent arcs were not handled. A round corner is now added if the deviation from one arc to the next is greater than a suitable threshold. o The current direction wasn't retained if a the outline contained a zero length lineto or a curve that was determined to be `basically a point'. This could cause a spurious join to be added. o Cubics with close control points could be mishandled. All eight cases are now distinguished correctly. Other improvements ------------------ o Borders for cubic curves could be too `flat'. FT_SMALL_CUBIC_THRESHOLD has been reduced a little to prevent this. o The handling and use of movable points has been simplified a little. o Various values are now computed only if the results are actually needed. o The directions of the outer and inner borders have been swapped, as recommended by Graham Asher. * src/base/ftstroke.c: Revised. * include/freetype/ftstroke.h: Updated.
2011-07-02 12:09:52 +02:00
/* compute median angle */
phi = stroker->angle_in + theta;
thcos = FT_Cos( theta );
length = FT_DivFix( stroker->radius, thcos );
FT_Vector_From_Polar( &delta, length, phi + rotate );
delta.x += stroker->center.x;
delta.y += stroker->center.y;
}
2008-09-16 19:32:02 +02:00
error = ft_stroke_border_lineto( border, &delta, FALSE );
return error;
}
/* process an outside corner, i.e. compute bevel/miter/round */
static FT_Error
ft_stroker_outside( FT_Stroker stroker,
[ftstroke] Major revision. The main problems ----------------- o If FT_STROKER_LINEJOIN_BEVEL was specified, unlimited miter joins (not bevel joins) were generated. Indeed, the meanings of `miter' and `bevel' were incorrectly reversed (consistently) in both the code and comments. o The way bevel joins were constructed (whether specified explicitly, or created as a result of exceeding the miter limit) did not match what is required for stroked text in PostScript or PDF. The main fixes -------------- o The behaviour of FT_STROKER_LINEJOIN_BEVEL has been corrected. o A new line join style, FT_STROKER_LINEJOIN_MITER_FIXED, has been introduced to support PostScript and PDF miter joins. o FT_STROKER_LINEJOIN_MITER_VARIABLE has been introduced as an alias for FT_STROKER_LINEJOIN_MITER. Additionally, a variety of stroking errors have been fixed. These would cause various artifacts (including points `at infinity'), especially when stroking poor quality fonts. See http://lists.gnu.org/archive/html/freetype-devel/2011-07/msg00001.html for example documents. The FreeType stroker now produces results very similar to that produced by GhostScript and Distiller for these fonts. Other problems -------------- The following problems have been resolved: o Inside corners could be generated incorrectly. Intersecting the inside corner could cause a missing triangular area and other effects. The intersection point can only be used if the join is between two lines and both lines are long enough. The `optimization' condition in `ft_stroker_inside' has been corrected; this requires the line length to be passed into various functions and stored in `FT_StrokerRec'. o Incorrect cubic curves could be generated. The angle calculations in `FT_Stroker_CubicTo' have been corrected to handle the case of the curve crossing the +/-PI direction. o If the border radius was greater than the radius of curvature of a curve, then the negative sector would end up outside (not inside) the border. This situation is now recognized and the negative sector is circumnavigated in the opposite direction. (If round line joins are being used, this code is disabled because the line join will always cover the negative sector.) o When a curve is split, the arcs may not join smoothly (especially if the curve turns sharply back on itself). Changes in direction between adjacent arcs were not handled. A round corner is now added if the deviation from one arc to the next is greater than a suitable threshold. o The current direction wasn't retained if a the outline contained a zero length lineto or a curve that was determined to be `basically a point'. This could cause a spurious join to be added. o Cubics with close control points could be mishandled. All eight cases are now distinguished correctly. Other improvements ------------------ o Borders for cubic curves could be too `flat'. FT_SMALL_CUBIC_THRESHOLD has been reduced a little to prevent this. o The handling and use of movable points has been simplified a little. o Various values are now computed only if the results are actually needed. o The directions of the outer and inner borders have been swapped, as recommended by Graham Asher. * src/base/ftstroke.c: Revised. * include/freetype/ftstroke.h: Updated.
2011-07-02 12:09:52 +02:00
FT_Int side,
FT_Fixed line_length )
{
FT_StrokeBorder border = stroker->borders + side;
FT_Error error;
FT_Angle rotate;
if ( stroker->line_join == FT_STROKER_LINEJOIN_ROUND )
error = ft_stroker_arcto( stroker, side );
else
{
[ftstroke] Major revision. The main problems ----------------- o If FT_STROKER_LINEJOIN_BEVEL was specified, unlimited miter joins (not bevel joins) were generated. Indeed, the meanings of `miter' and `bevel' were incorrectly reversed (consistently) in both the code and comments. o The way bevel joins were constructed (whether specified explicitly, or created as a result of exceeding the miter limit) did not match what is required for stroked text in PostScript or PDF. The main fixes -------------- o The behaviour of FT_STROKER_LINEJOIN_BEVEL has been corrected. o A new line join style, FT_STROKER_LINEJOIN_MITER_FIXED, has been introduced to support PostScript and PDF miter joins. o FT_STROKER_LINEJOIN_MITER_VARIABLE has been introduced as an alias for FT_STROKER_LINEJOIN_MITER. Additionally, a variety of stroking errors have been fixed. These would cause various artifacts (including points `at infinity'), especially when stroking poor quality fonts. See http://lists.gnu.org/archive/html/freetype-devel/2011-07/msg00001.html for example documents. The FreeType stroker now produces results very similar to that produced by GhostScript and Distiller for these fonts. Other problems -------------- The following problems have been resolved: o Inside corners could be generated incorrectly. Intersecting the inside corner could cause a missing triangular area and other effects. The intersection point can only be used if the join is between two lines and both lines are long enough. The `optimization' condition in `ft_stroker_inside' has been corrected; this requires the line length to be passed into various functions and stored in `FT_StrokerRec'. o Incorrect cubic curves could be generated. The angle calculations in `FT_Stroker_CubicTo' have been corrected to handle the case of the curve crossing the +/-PI direction. o If the border radius was greater than the radius of curvature of a curve, then the negative sector would end up outside (not inside) the border. This situation is now recognized and the negative sector is circumnavigated in the opposite direction. (If round line joins are being used, this code is disabled because the line join will always cover the negative sector.) o When a curve is split, the arcs may not join smoothly (especially if the curve turns sharply back on itself). Changes in direction between adjacent arcs were not handled. A round corner is now added if the deviation from one arc to the next is greater than a suitable threshold. o The current direction wasn't retained if a the outline contained a zero length lineto or a curve that was determined to be `basically a point'. This could cause a spurious join to be added. o Cubics with close control points could be mishandled. All eight cases are now distinguished correctly. Other improvements ------------------ o Borders for cubic curves could be too `flat'. FT_SMALL_CUBIC_THRESHOLD has been reduced a little to prevent this. o The handling and use of movable points has been simplified a little. o Various values are now computed only if the results are actually needed. o The directions of the outer and inner borders have been swapped, as recommended by Graham Asher. * src/base/ftstroke.c: Revised. * include/freetype/ftstroke.h: Updated.
2011-07-02 12:09:52 +02:00
/* this is a mitered (pointed) or beveled (truncated) corner */
FT_Fixed sigma = 0, radius = stroker->radius;
FT_Angle theta = 0, phi = 0;
FT_Fixed thcos = 0;
FT_Bool bevel, fixed_bevel;
rotate = FT_SIDE_TO_ROTATE( side );
[ftstroke] Major revision. The main problems ----------------- o If FT_STROKER_LINEJOIN_BEVEL was specified, unlimited miter joins (not bevel joins) were generated. Indeed, the meanings of `miter' and `bevel' were incorrectly reversed (consistently) in both the code and comments. o The way bevel joins were constructed (whether specified explicitly, or created as a result of exceeding the miter limit) did not match what is required for stroked text in PostScript or PDF. The main fixes -------------- o The behaviour of FT_STROKER_LINEJOIN_BEVEL has been corrected. o A new line join style, FT_STROKER_LINEJOIN_MITER_FIXED, has been introduced to support PostScript and PDF miter joins. o FT_STROKER_LINEJOIN_MITER_VARIABLE has been introduced as an alias for FT_STROKER_LINEJOIN_MITER. Additionally, a variety of stroking errors have been fixed. These would cause various artifacts (including points `at infinity'), especially when stroking poor quality fonts. See http://lists.gnu.org/archive/html/freetype-devel/2011-07/msg00001.html for example documents. The FreeType stroker now produces results very similar to that produced by GhostScript and Distiller for these fonts. Other problems -------------- The following problems have been resolved: o Inside corners could be generated incorrectly. Intersecting the inside corner could cause a missing triangular area and other effects. The intersection point can only be used if the join is between two lines and both lines are long enough. The `optimization' condition in `ft_stroker_inside' has been corrected; this requires the line length to be passed into various functions and stored in `FT_StrokerRec'. o Incorrect cubic curves could be generated. The angle calculations in `FT_Stroker_CubicTo' have been corrected to handle the case of the curve crossing the +/-PI direction. o If the border radius was greater than the radius of curvature of a curve, then the negative sector would end up outside (not inside) the border. This situation is now recognized and the negative sector is circumnavigated in the opposite direction. (If round line joins are being used, this code is disabled because the line join will always cover the negative sector.) o When a curve is split, the arcs may not join smoothly (especially if the curve turns sharply back on itself). Changes in direction between adjacent arcs were not handled. A round corner is now added if the deviation from one arc to the next is greater than a suitable threshold. o The current direction wasn't retained if a the outline contained a zero length lineto or a curve that was determined to be `basically a point'. This could cause a spurious join to be added. o Cubics with close control points could be mishandled. All eight cases are now distinguished correctly. Other improvements ------------------ o Borders for cubic curves could be too `flat'. FT_SMALL_CUBIC_THRESHOLD has been reduced a little to prevent this. o The handling and use of movable points has been simplified a little. o Various values are now computed only if the results are actually needed. o The directions of the outer and inner borders have been swapped, as recommended by Graham Asher. * src/base/ftstroke.c: Revised. * include/freetype/ftstroke.h: Updated.
2011-07-02 12:09:52 +02:00
bevel =
FT_BOOL( stroker->line_join == FT_STROKER_LINEJOIN_BEVEL );
fixed_bevel =
FT_BOOL( stroker->line_join != FT_STROKER_LINEJOIN_MITER_VARIABLE );
if ( !bevel )
{
[ftstroke] Major revision. The main problems ----------------- o If FT_STROKER_LINEJOIN_BEVEL was specified, unlimited miter joins (not bevel joins) were generated. Indeed, the meanings of `miter' and `bevel' were incorrectly reversed (consistently) in both the code and comments. o The way bevel joins were constructed (whether specified explicitly, or created as a result of exceeding the miter limit) did not match what is required for stroked text in PostScript or PDF. The main fixes -------------- o The behaviour of FT_STROKER_LINEJOIN_BEVEL has been corrected. o A new line join style, FT_STROKER_LINEJOIN_MITER_FIXED, has been introduced to support PostScript and PDF miter joins. o FT_STROKER_LINEJOIN_MITER_VARIABLE has been introduced as an alias for FT_STROKER_LINEJOIN_MITER. Additionally, a variety of stroking errors have been fixed. These would cause various artifacts (including points `at infinity'), especially when stroking poor quality fonts. See http://lists.gnu.org/archive/html/freetype-devel/2011-07/msg00001.html for example documents. The FreeType stroker now produces results very similar to that produced by GhostScript and Distiller for these fonts. Other problems -------------- The following problems have been resolved: o Inside corners could be generated incorrectly. Intersecting the inside corner could cause a missing triangular area and other effects. The intersection point can only be used if the join is between two lines and both lines are long enough. The `optimization' condition in `ft_stroker_inside' has been corrected; this requires the line length to be passed into various functions and stored in `FT_StrokerRec'. o Incorrect cubic curves could be generated. The angle calculations in `FT_Stroker_CubicTo' have been corrected to handle the case of the curve crossing the +/-PI direction. o If the border radius was greater than the radius of curvature of a curve, then the negative sector would end up outside (not inside) the border. This situation is now recognized and the negative sector is circumnavigated in the opposite direction. (If round line joins are being used, this code is disabled because the line join will always cover the negative sector.) o When a curve is split, the arcs may not join smoothly (especially if the curve turns sharply back on itself). Changes in direction between adjacent arcs were not handled. A round corner is now added if the deviation from one arc to the next is greater than a suitable threshold. o The current direction wasn't retained if a the outline contained a zero length lineto or a curve that was determined to be `basically a point'. This could cause a spurious join to be added. o Cubics with close control points could be mishandled. All eight cases are now distinguished correctly. Other improvements ------------------ o Borders for cubic curves could be too `flat'. FT_SMALL_CUBIC_THRESHOLD has been reduced a little to prevent this. o The handling and use of movable points has been simplified a little. o Various values are now computed only if the results are actually needed. o The directions of the outer and inner borders have been swapped, as recommended by Graham Asher. * src/base/ftstroke.c: Revised. * include/freetype/ftstroke.h: Updated.
2011-07-02 12:09:52 +02:00
theta = FT_Angle_Diff( stroker->angle_in, stroker->angle_out );
if ( theta == FT_ANGLE_PI )
{
theta = rotate;
phi = stroker->angle_in;
}
else
{
theta /= 2;
phi = stroker->angle_in + theta + rotate;
}
thcos = FT_Cos( theta );
sigma = FT_MulFix( stroker->miter_limit, thcos );
/* is miter limit exceeded? */
if ( sigma < 0x10000L )
{
/* don't create variable bevels for very small deviations; */
/* FT_Sin(x) = 0 for x <= 57 */
if ( fixed_bevel || ft_pos_abs( theta ) > 57 )
bevel = TRUE;
}
}
[ftstroke] Major revision. The main problems ----------------- o If FT_STROKER_LINEJOIN_BEVEL was specified, unlimited miter joins (not bevel joins) were generated. Indeed, the meanings of `miter' and `bevel' were incorrectly reversed (consistently) in both the code and comments. o The way bevel joins were constructed (whether specified explicitly, or created as a result of exceeding the miter limit) did not match what is required for stroked text in PostScript or PDF. The main fixes -------------- o The behaviour of FT_STROKER_LINEJOIN_BEVEL has been corrected. o A new line join style, FT_STROKER_LINEJOIN_MITER_FIXED, has been introduced to support PostScript and PDF miter joins. o FT_STROKER_LINEJOIN_MITER_VARIABLE has been introduced as an alias for FT_STROKER_LINEJOIN_MITER. Additionally, a variety of stroking errors have been fixed. These would cause various artifacts (including points `at infinity'), especially when stroking poor quality fonts. See http://lists.gnu.org/archive/html/freetype-devel/2011-07/msg00001.html for example documents. The FreeType stroker now produces results very similar to that produced by GhostScript and Distiller for these fonts. Other problems -------------- The following problems have been resolved: o Inside corners could be generated incorrectly. Intersecting the inside corner could cause a missing triangular area and other effects. The intersection point can only be used if the join is between two lines and both lines are long enough. The `optimization' condition in `ft_stroker_inside' has been corrected; this requires the line length to be passed into various functions and stored in `FT_StrokerRec'. o Incorrect cubic curves could be generated. The angle calculations in `FT_Stroker_CubicTo' have been corrected to handle the case of the curve crossing the +/-PI direction. o If the border radius was greater than the radius of curvature of a curve, then the negative sector would end up outside (not inside) the border. This situation is now recognized and the negative sector is circumnavigated in the opposite direction. (If round line joins are being used, this code is disabled because the line join will always cover the negative sector.) o When a curve is split, the arcs may not join smoothly (especially if the curve turns sharply back on itself). Changes in direction between adjacent arcs were not handled. A round corner is now added if the deviation from one arc to the next is greater than a suitable threshold. o The current direction wasn't retained if a the outline contained a zero length lineto or a curve that was determined to be `basically a point'. This could cause a spurious join to be added. o Cubics with close control points could be mishandled. All eight cases are now distinguished correctly. Other improvements ------------------ o Borders for cubic curves could be too `flat'. FT_SMALL_CUBIC_THRESHOLD has been reduced a little to prevent this. o The handling and use of movable points has been simplified a little. o Various values are now computed only if the results are actually needed. o The directions of the outer and inner borders have been swapped, as recommended by Graham Asher. * src/base/ftstroke.c: Revised. * include/freetype/ftstroke.h: Updated.
2011-07-02 12:09:52 +02:00
if ( bevel ) /* this is a bevel (broken angle) */
{
[ftstroke] Major revision. The main problems ----------------- o If FT_STROKER_LINEJOIN_BEVEL was specified, unlimited miter joins (not bevel joins) were generated. Indeed, the meanings of `miter' and `bevel' were incorrectly reversed (consistently) in both the code and comments. o The way bevel joins were constructed (whether specified explicitly, or created as a result of exceeding the miter limit) did not match what is required for stroked text in PostScript or PDF. The main fixes -------------- o The behaviour of FT_STROKER_LINEJOIN_BEVEL has been corrected. o A new line join style, FT_STROKER_LINEJOIN_MITER_FIXED, has been introduced to support PostScript and PDF miter joins. o FT_STROKER_LINEJOIN_MITER_VARIABLE has been introduced as an alias for FT_STROKER_LINEJOIN_MITER. Additionally, a variety of stroking errors have been fixed. These would cause various artifacts (including points `at infinity'), especially when stroking poor quality fonts. See http://lists.gnu.org/archive/html/freetype-devel/2011-07/msg00001.html for example documents. The FreeType stroker now produces results very similar to that produced by GhostScript and Distiller for these fonts. Other problems -------------- The following problems have been resolved: o Inside corners could be generated incorrectly. Intersecting the inside corner could cause a missing triangular area and other effects. The intersection point can only be used if the join is between two lines and both lines are long enough. The `optimization' condition in `ft_stroker_inside' has been corrected; this requires the line length to be passed into various functions and stored in `FT_StrokerRec'. o Incorrect cubic curves could be generated. The angle calculations in `FT_Stroker_CubicTo' have been corrected to handle the case of the curve crossing the +/-PI direction. o If the border radius was greater than the radius of curvature of a curve, then the negative sector would end up outside (not inside) the border. This situation is now recognized and the negative sector is circumnavigated in the opposite direction. (If round line joins are being used, this code is disabled because the line join will always cover the negative sector.) o When a curve is split, the arcs may not join smoothly (especially if the curve turns sharply back on itself). Changes in direction between adjacent arcs were not handled. A round corner is now added if the deviation from one arc to the next is greater than a suitable threshold. o The current direction wasn't retained if a the outline contained a zero length lineto or a curve that was determined to be `basically a point'. This could cause a spurious join to be added. o Cubics with close control points could be mishandled. All eight cases are now distinguished correctly. Other improvements ------------------ o Borders for cubic curves could be too `flat'. FT_SMALL_CUBIC_THRESHOLD has been reduced a little to prevent this. o The handling and use of movable points has been simplified a little. o Various values are now computed only if the results are actually needed. o The directions of the outer and inner borders have been swapped, as recommended by Graham Asher. * src/base/ftstroke.c: Revised. * include/freetype/ftstroke.h: Updated.
2011-07-02 12:09:52 +02:00
if ( fixed_bevel )
{
/* the outer corners are simply joined together */
FT_Vector delta;
[ftstroke] Major revision. The main problems ----------------- o If FT_STROKER_LINEJOIN_BEVEL was specified, unlimited miter joins (not bevel joins) were generated. Indeed, the meanings of `miter' and `bevel' were incorrectly reversed (consistently) in both the code and comments. o The way bevel joins were constructed (whether specified explicitly, or created as a result of exceeding the miter limit) did not match what is required for stroked text in PostScript or PDF. The main fixes -------------- o The behaviour of FT_STROKER_LINEJOIN_BEVEL has been corrected. o A new line join style, FT_STROKER_LINEJOIN_MITER_FIXED, has been introduced to support PostScript and PDF miter joins. o FT_STROKER_LINEJOIN_MITER_VARIABLE has been introduced as an alias for FT_STROKER_LINEJOIN_MITER. Additionally, a variety of stroking errors have been fixed. These would cause various artifacts (including points `at infinity'), especially when stroking poor quality fonts. See http://lists.gnu.org/archive/html/freetype-devel/2011-07/msg00001.html for example documents. The FreeType stroker now produces results very similar to that produced by GhostScript and Distiller for these fonts. Other problems -------------- The following problems have been resolved: o Inside corners could be generated incorrectly. Intersecting the inside corner could cause a missing triangular area and other effects. The intersection point can only be used if the join is between two lines and both lines are long enough. The `optimization' condition in `ft_stroker_inside' has been corrected; this requires the line length to be passed into various functions and stored in `FT_StrokerRec'. o Incorrect cubic curves could be generated. The angle calculations in `FT_Stroker_CubicTo' have been corrected to handle the case of the curve crossing the +/-PI direction. o If the border radius was greater than the radius of curvature of a curve, then the negative sector would end up outside (not inside) the border. This situation is now recognized and the negative sector is circumnavigated in the opposite direction. (If round line joins are being used, this code is disabled because the line join will always cover the negative sector.) o When a curve is split, the arcs may not join smoothly (especially if the curve turns sharply back on itself). Changes in direction between adjacent arcs were not handled. A round corner is now added if the deviation from one arc to the next is greater than a suitable threshold. o The current direction wasn't retained if a the outline contained a zero length lineto or a curve that was determined to be `basically a point'. This could cause a spurious join to be added. o Cubics with close control points could be mishandled. All eight cases are now distinguished correctly. Other improvements ------------------ o Borders for cubic curves could be too `flat'. FT_SMALL_CUBIC_THRESHOLD has been reduced a little to prevent this. o The handling and use of movable points has been simplified a little. o Various values are now computed only if the results are actually needed. o The directions of the outer and inner borders have been swapped, as recommended by Graham Asher. * src/base/ftstroke.c: Revised. * include/freetype/ftstroke.h: Updated.
2011-07-02 12:09:52 +02:00
/* add bevel */
FT_Vector_From_Polar( &delta,
radius,
stroker->angle_out + rotate );
delta.x += stroker->center.x;
delta.y += stroker->center.y;
[ftstroke] Major revision. The main problems ----------------- o If FT_STROKER_LINEJOIN_BEVEL was specified, unlimited miter joins (not bevel joins) were generated. Indeed, the meanings of `miter' and `bevel' were incorrectly reversed (consistently) in both the code and comments. o The way bevel joins were constructed (whether specified explicitly, or created as a result of exceeding the miter limit) did not match what is required for stroked text in PostScript or PDF. The main fixes -------------- o The behaviour of FT_STROKER_LINEJOIN_BEVEL has been corrected. o A new line join style, FT_STROKER_LINEJOIN_MITER_FIXED, has been introduced to support PostScript and PDF miter joins. o FT_STROKER_LINEJOIN_MITER_VARIABLE has been introduced as an alias for FT_STROKER_LINEJOIN_MITER. Additionally, a variety of stroking errors have been fixed. These would cause various artifacts (including points `at infinity'), especially when stroking poor quality fonts. See http://lists.gnu.org/archive/html/freetype-devel/2011-07/msg00001.html for example documents. The FreeType stroker now produces results very similar to that produced by GhostScript and Distiller for these fonts. Other problems -------------- The following problems have been resolved: o Inside corners could be generated incorrectly. Intersecting the inside corner could cause a missing triangular area and other effects. The intersection point can only be used if the join is between two lines and both lines are long enough. The `optimization' condition in `ft_stroker_inside' has been corrected; this requires the line length to be passed into various functions and stored in `FT_StrokerRec'. o Incorrect cubic curves could be generated. The angle calculations in `FT_Stroker_CubicTo' have been corrected to handle the case of the curve crossing the +/-PI direction. o If the border radius was greater than the radius of curvature of a curve, then the negative sector would end up outside (not inside) the border. This situation is now recognized and the negative sector is circumnavigated in the opposite direction. (If round line joins are being used, this code is disabled because the line join will always cover the negative sector.) o When a curve is split, the arcs may not join smoothly (especially if the curve turns sharply back on itself). Changes in direction between adjacent arcs were not handled. A round corner is now added if the deviation from one arc to the next is greater than a suitable threshold. o The current direction wasn't retained if a the outline contained a zero length lineto or a curve that was determined to be `basically a point'. This could cause a spurious join to be added. o Cubics with close control points could be mishandled. All eight cases are now distinguished correctly. Other improvements ------------------ o Borders for cubic curves could be too `flat'. FT_SMALL_CUBIC_THRESHOLD has been reduced a little to prevent this. o The handling and use of movable points has been simplified a little. o Various values are now computed only if the results are actually needed. o The directions of the outer and inner borders have been swapped, as recommended by Graham Asher. * src/base/ftstroke.c: Revised. * include/freetype/ftstroke.h: Updated.
2011-07-02 12:09:52 +02:00
border->movable = FALSE;
error = ft_stroke_border_lineto( border, &delta, FALSE );
}
else /* variable bevel */
{
/* the miter is truncated */
FT_Vector middle, delta;
FT_Fixed length;
[ftstroke] Major revision. The main problems ----------------- o If FT_STROKER_LINEJOIN_BEVEL was specified, unlimited miter joins (not bevel joins) were generated. Indeed, the meanings of `miter' and `bevel' were incorrectly reversed (consistently) in both the code and comments. o The way bevel joins were constructed (whether specified explicitly, or created as a result of exceeding the miter limit) did not match what is required for stroked text in PostScript or PDF. The main fixes -------------- o The behaviour of FT_STROKER_LINEJOIN_BEVEL has been corrected. o A new line join style, FT_STROKER_LINEJOIN_MITER_FIXED, has been introduced to support PostScript and PDF miter joins. o FT_STROKER_LINEJOIN_MITER_VARIABLE has been introduced as an alias for FT_STROKER_LINEJOIN_MITER. Additionally, a variety of stroking errors have been fixed. These would cause various artifacts (including points `at infinity'), especially when stroking poor quality fonts. See http://lists.gnu.org/archive/html/freetype-devel/2011-07/msg00001.html for example documents. The FreeType stroker now produces results very similar to that produced by GhostScript and Distiller for these fonts. Other problems -------------- The following problems have been resolved: o Inside corners could be generated incorrectly. Intersecting the inside corner could cause a missing triangular area and other effects. The intersection point can only be used if the join is between two lines and both lines are long enough. The `optimization' condition in `ft_stroker_inside' has been corrected; this requires the line length to be passed into various functions and stored in `FT_StrokerRec'. o Incorrect cubic curves could be generated. The angle calculations in `FT_Stroker_CubicTo' have been corrected to handle the case of the curve crossing the +/-PI direction. o If the border radius was greater than the radius of curvature of a curve, then the negative sector would end up outside (not inside) the border. This situation is now recognized and the negative sector is circumnavigated in the opposite direction. (If round line joins are being used, this code is disabled because the line join will always cover the negative sector.) o When a curve is split, the arcs may not join smoothly (especially if the curve turns sharply back on itself). Changes in direction between adjacent arcs were not handled. A round corner is now added if the deviation from one arc to the next is greater than a suitable threshold. o The current direction wasn't retained if a the outline contained a zero length lineto or a curve that was determined to be `basically a point'. This could cause a spurious join to be added. o Cubics with close control points could be mishandled. All eight cases are now distinguished correctly. Other improvements ------------------ o Borders for cubic curves could be too `flat'. FT_SMALL_CUBIC_THRESHOLD has been reduced a little to prevent this. o The handling and use of movable points has been simplified a little. o Various values are now computed only if the results are actually needed. o The directions of the outer and inner borders have been swapped, as recommended by Graham Asher. * src/base/ftstroke.c: Revised. * include/freetype/ftstroke.h: Updated.
2011-07-02 12:09:52 +02:00
/* compute middle point */
FT_Vector_From_Polar( &middle,
FT_MulFix( radius, stroker->miter_limit ),
phi );
middle.x += stroker->center.x;
middle.y += stroker->center.y;
[ftstroke] Major revision. The main problems ----------------- o If FT_STROKER_LINEJOIN_BEVEL was specified, unlimited miter joins (not bevel joins) were generated. Indeed, the meanings of `miter' and `bevel' were incorrectly reversed (consistently) in both the code and comments. o The way bevel joins were constructed (whether specified explicitly, or created as a result of exceeding the miter limit) did not match what is required for stroked text in PostScript or PDF. The main fixes -------------- o The behaviour of FT_STROKER_LINEJOIN_BEVEL has been corrected. o A new line join style, FT_STROKER_LINEJOIN_MITER_FIXED, has been introduced to support PostScript and PDF miter joins. o FT_STROKER_LINEJOIN_MITER_VARIABLE has been introduced as an alias for FT_STROKER_LINEJOIN_MITER. Additionally, a variety of stroking errors have been fixed. These would cause various artifacts (including points `at infinity'), especially when stroking poor quality fonts. See http://lists.gnu.org/archive/html/freetype-devel/2011-07/msg00001.html for example documents. The FreeType stroker now produces results very similar to that produced by GhostScript and Distiller for these fonts. Other problems -------------- The following problems have been resolved: o Inside corners could be generated incorrectly. Intersecting the inside corner could cause a missing triangular area and other effects. The intersection point can only be used if the join is between two lines and both lines are long enough. The `optimization' condition in `ft_stroker_inside' has been corrected; this requires the line length to be passed into various functions and stored in `FT_StrokerRec'. o Incorrect cubic curves could be generated. The angle calculations in `FT_Stroker_CubicTo' have been corrected to handle the case of the curve crossing the +/-PI direction. o If the border radius was greater than the radius of curvature of a curve, then the negative sector would end up outside (not inside) the border. This situation is now recognized and the negative sector is circumnavigated in the opposite direction. (If round line joins are being used, this code is disabled because the line join will always cover the negative sector.) o When a curve is split, the arcs may not join smoothly (especially if the curve turns sharply back on itself). Changes in direction between adjacent arcs were not handled. A round corner is now added if the deviation from one arc to the next is greater than a suitable threshold. o The current direction wasn't retained if a the outline contained a zero length lineto or a curve that was determined to be `basically a point'. This could cause a spurious join to be added. o Cubics with close control points could be mishandled. All eight cases are now distinguished correctly. Other improvements ------------------ o Borders for cubic curves could be too `flat'. FT_SMALL_CUBIC_THRESHOLD has been reduced a little to prevent this. o The handling and use of movable points has been simplified a little. o Various values are now computed only if the results are actually needed. o The directions of the outer and inner borders have been swapped, as recommended by Graham Asher. * src/base/ftstroke.c: Revised. * include/freetype/ftstroke.h: Updated.
2011-07-02 12:09:52 +02:00
/* compute first angle point */
length = FT_MulDiv( radius, 0x10000L - sigma,
ft_pos_abs( FT_Sin( theta ) ) );
[ftstroke] Major revision. The main problems ----------------- o If FT_STROKER_LINEJOIN_BEVEL was specified, unlimited miter joins (not bevel joins) were generated. Indeed, the meanings of `miter' and `bevel' were incorrectly reversed (consistently) in both the code and comments. o The way bevel joins were constructed (whether specified explicitly, or created as a result of exceeding the miter limit) did not match what is required for stroked text in PostScript or PDF. The main fixes -------------- o The behaviour of FT_STROKER_LINEJOIN_BEVEL has been corrected. o A new line join style, FT_STROKER_LINEJOIN_MITER_FIXED, has been introduced to support PostScript and PDF miter joins. o FT_STROKER_LINEJOIN_MITER_VARIABLE has been introduced as an alias for FT_STROKER_LINEJOIN_MITER. Additionally, a variety of stroking errors have been fixed. These would cause various artifacts (including points `at infinity'), especially when stroking poor quality fonts. See http://lists.gnu.org/archive/html/freetype-devel/2011-07/msg00001.html for example documents. The FreeType stroker now produces results very similar to that produced by GhostScript and Distiller for these fonts. Other problems -------------- The following problems have been resolved: o Inside corners could be generated incorrectly. Intersecting the inside corner could cause a missing triangular area and other effects. The intersection point can only be used if the join is between two lines and both lines are long enough. The `optimization' condition in `ft_stroker_inside' has been corrected; this requires the line length to be passed into various functions and stored in `FT_StrokerRec'. o Incorrect cubic curves could be generated. The angle calculations in `FT_Stroker_CubicTo' have been corrected to handle the case of the curve crossing the +/-PI direction. o If the border radius was greater than the radius of curvature of a curve, then the negative sector would end up outside (not inside) the border. This situation is now recognized and the negative sector is circumnavigated in the opposite direction. (If round line joins are being used, this code is disabled because the line join will always cover the negative sector.) o When a curve is split, the arcs may not join smoothly (especially if the curve turns sharply back on itself). Changes in direction between adjacent arcs were not handled. A round corner is now added if the deviation from one arc to the next is greater than a suitable threshold. o The current direction wasn't retained if a the outline contained a zero length lineto or a curve that was determined to be `basically a point'. This could cause a spurious join to be added. o Cubics with close control points could be mishandled. All eight cases are now distinguished correctly. Other improvements ------------------ o Borders for cubic curves could be too `flat'. FT_SMALL_CUBIC_THRESHOLD has been reduced a little to prevent this. o The handling and use of movable points has been simplified a little. o Various values are now computed only if the results are actually needed. o The directions of the outer and inner borders have been swapped, as recommended by Graham Asher. * src/base/ftstroke.c: Revised. * include/freetype/ftstroke.h: Updated.
2011-07-02 12:09:52 +02:00
FT_Vector_From_Polar( &delta, length, phi + rotate );
delta.x += middle.x;
delta.y += middle.y;
[ftstroke] Major revision. The main problems ----------------- o If FT_STROKER_LINEJOIN_BEVEL was specified, unlimited miter joins (not bevel joins) were generated. Indeed, the meanings of `miter' and `bevel' were incorrectly reversed (consistently) in both the code and comments. o The way bevel joins were constructed (whether specified explicitly, or created as a result of exceeding the miter limit) did not match what is required for stroked text in PostScript or PDF. The main fixes -------------- o The behaviour of FT_STROKER_LINEJOIN_BEVEL has been corrected. o A new line join style, FT_STROKER_LINEJOIN_MITER_FIXED, has been introduced to support PostScript and PDF miter joins. o FT_STROKER_LINEJOIN_MITER_VARIABLE has been introduced as an alias for FT_STROKER_LINEJOIN_MITER. Additionally, a variety of stroking errors have been fixed. These would cause various artifacts (including points `at infinity'), especially when stroking poor quality fonts. See http://lists.gnu.org/archive/html/freetype-devel/2011-07/msg00001.html for example documents. The FreeType stroker now produces results very similar to that produced by GhostScript and Distiller for these fonts. Other problems -------------- The following problems have been resolved: o Inside corners could be generated incorrectly. Intersecting the inside corner could cause a missing triangular area and other effects. The intersection point can only be used if the join is between two lines and both lines are long enough. The `optimization' condition in `ft_stroker_inside' has been corrected; this requires the line length to be passed into various functions and stored in `FT_StrokerRec'. o Incorrect cubic curves could be generated. The angle calculations in `FT_Stroker_CubicTo' have been corrected to handle the case of the curve crossing the +/-PI direction. o If the border radius was greater than the radius of curvature of a curve, then the negative sector would end up outside (not inside) the border. This situation is now recognized and the negative sector is circumnavigated in the opposite direction. (If round line joins are being used, this code is disabled because the line join will always cover the negative sector.) o When a curve is split, the arcs may not join smoothly (especially if the curve turns sharply back on itself). Changes in direction between adjacent arcs were not handled. A round corner is now added if the deviation from one arc to the next is greater than a suitable threshold. o The current direction wasn't retained if a the outline contained a zero length lineto or a curve that was determined to be `basically a point'. This could cause a spurious join to be added. o Cubics with close control points could be mishandled. All eight cases are now distinguished correctly. Other improvements ------------------ o Borders for cubic curves could be too `flat'. FT_SMALL_CUBIC_THRESHOLD has been reduced a little to prevent this. o The handling and use of movable points has been simplified a little. o Various values are now computed only if the results are actually needed. o The directions of the outer and inner borders have been swapped, as recommended by Graham Asher. * src/base/ftstroke.c: Revised. * include/freetype/ftstroke.h: Updated.
2011-07-02 12:09:52 +02:00
error = ft_stroke_border_lineto( border, &delta, FALSE );
if ( error )
goto Exit;
[ftstroke] Major revision. The main problems ----------------- o If FT_STROKER_LINEJOIN_BEVEL was specified, unlimited miter joins (not bevel joins) were generated. Indeed, the meanings of `miter' and `bevel' were incorrectly reversed (consistently) in both the code and comments. o The way bevel joins were constructed (whether specified explicitly, or created as a result of exceeding the miter limit) did not match what is required for stroked text in PostScript or PDF. The main fixes -------------- o The behaviour of FT_STROKER_LINEJOIN_BEVEL has been corrected. o A new line join style, FT_STROKER_LINEJOIN_MITER_FIXED, has been introduced to support PostScript and PDF miter joins. o FT_STROKER_LINEJOIN_MITER_VARIABLE has been introduced as an alias for FT_STROKER_LINEJOIN_MITER. Additionally, a variety of stroking errors have been fixed. These would cause various artifacts (including points `at infinity'), especially when stroking poor quality fonts. See http://lists.gnu.org/archive/html/freetype-devel/2011-07/msg00001.html for example documents. The FreeType stroker now produces results very similar to that produced by GhostScript and Distiller for these fonts. Other problems -------------- The following problems have been resolved: o Inside corners could be generated incorrectly. Intersecting the inside corner could cause a missing triangular area and other effects. The intersection point can only be used if the join is between two lines and both lines are long enough. The `optimization' condition in `ft_stroker_inside' has been corrected; this requires the line length to be passed into various functions and stored in `FT_StrokerRec'. o Incorrect cubic curves could be generated. The angle calculations in `FT_Stroker_CubicTo' have been corrected to handle the case of the curve crossing the +/-PI direction. o If the border radius was greater than the radius of curvature of a curve, then the negative sector would end up outside (not inside) the border. This situation is now recognized and the negative sector is circumnavigated in the opposite direction. (If round line joins are being used, this code is disabled because the line join will always cover the negative sector.) o When a curve is split, the arcs may not join smoothly (especially if the curve turns sharply back on itself). Changes in direction between adjacent arcs were not handled. A round corner is now added if the deviation from one arc to the next is greater than a suitable threshold. o The current direction wasn't retained if a the outline contained a zero length lineto or a curve that was determined to be `basically a point'. This could cause a spurious join to be added. o Cubics with close control points could be mishandled. All eight cases are now distinguished correctly. Other improvements ------------------ o Borders for cubic curves could be too `flat'. FT_SMALL_CUBIC_THRESHOLD has been reduced a little to prevent this. o The handling and use of movable points has been simplified a little. o Various values are now computed only if the results are actually needed. o The directions of the outer and inner borders have been swapped, as recommended by Graham Asher. * src/base/ftstroke.c: Revised. * include/freetype/ftstroke.h: Updated.
2011-07-02 12:09:52 +02:00
/* compute second angle point */
FT_Vector_From_Polar( &delta, length, phi - rotate );
delta.x += middle.x;
delta.y += middle.y;
[ftstroke] Major revision. The main problems ----------------- o If FT_STROKER_LINEJOIN_BEVEL was specified, unlimited miter joins (not bevel joins) were generated. Indeed, the meanings of `miter' and `bevel' were incorrectly reversed (consistently) in both the code and comments. o The way bevel joins were constructed (whether specified explicitly, or created as a result of exceeding the miter limit) did not match what is required for stroked text in PostScript or PDF. The main fixes -------------- o The behaviour of FT_STROKER_LINEJOIN_BEVEL has been corrected. o A new line join style, FT_STROKER_LINEJOIN_MITER_FIXED, has been introduced to support PostScript and PDF miter joins. o FT_STROKER_LINEJOIN_MITER_VARIABLE has been introduced as an alias for FT_STROKER_LINEJOIN_MITER. Additionally, a variety of stroking errors have been fixed. These would cause various artifacts (including points `at infinity'), especially when stroking poor quality fonts. See http://lists.gnu.org/archive/html/freetype-devel/2011-07/msg00001.html for example documents. The FreeType stroker now produces results very similar to that produced by GhostScript and Distiller for these fonts. Other problems -------------- The following problems have been resolved: o Inside corners could be generated incorrectly. Intersecting the inside corner could cause a missing triangular area and other effects. The intersection point can only be used if the join is between two lines and both lines are long enough. The `optimization' condition in `ft_stroker_inside' has been corrected; this requires the line length to be passed into various functions and stored in `FT_StrokerRec'. o Incorrect cubic curves could be generated. The angle calculations in `FT_Stroker_CubicTo' have been corrected to handle the case of the curve crossing the +/-PI direction. o If the border radius was greater than the radius of curvature of a curve, then the negative sector would end up outside (not inside) the border. This situation is now recognized and the negative sector is circumnavigated in the opposite direction. (If round line joins are being used, this code is disabled because the line join will always cover the negative sector.) o When a curve is split, the arcs may not join smoothly (especially if the curve turns sharply back on itself). Changes in direction between adjacent arcs were not handled. A round corner is now added if the deviation from one arc to the next is greater than a suitable threshold. o The current direction wasn't retained if a the outline contained a zero length lineto or a curve that was determined to be `basically a point'. This could cause a spurious join to be added. o Cubics with close control points could be mishandled. All eight cases are now distinguished correctly. Other improvements ------------------ o Borders for cubic curves could be too `flat'. FT_SMALL_CUBIC_THRESHOLD has been reduced a little to prevent this. o The handling and use of movable points has been simplified a little. o Various values are now computed only if the results are actually needed. o The directions of the outer and inner borders have been swapped, as recommended by Graham Asher. * src/base/ftstroke.c: Revised. * include/freetype/ftstroke.h: Updated.
2011-07-02 12:09:52 +02:00
error = ft_stroke_border_lineto( border, &delta, FALSE );
if ( error )
goto Exit;
[ftstroke] Major revision. The main problems ----------------- o If FT_STROKER_LINEJOIN_BEVEL was specified, unlimited miter joins (not bevel joins) were generated. Indeed, the meanings of `miter' and `bevel' were incorrectly reversed (consistently) in both the code and comments. o The way bevel joins were constructed (whether specified explicitly, or created as a result of exceeding the miter limit) did not match what is required for stroked text in PostScript or PDF. The main fixes -------------- o The behaviour of FT_STROKER_LINEJOIN_BEVEL has been corrected. o A new line join style, FT_STROKER_LINEJOIN_MITER_FIXED, has been introduced to support PostScript and PDF miter joins. o FT_STROKER_LINEJOIN_MITER_VARIABLE has been introduced as an alias for FT_STROKER_LINEJOIN_MITER. Additionally, a variety of stroking errors have been fixed. These would cause various artifacts (including points `at infinity'), especially when stroking poor quality fonts. See http://lists.gnu.org/archive/html/freetype-devel/2011-07/msg00001.html for example documents. The FreeType stroker now produces results very similar to that produced by GhostScript and Distiller for these fonts. Other problems -------------- The following problems have been resolved: o Inside corners could be generated incorrectly. Intersecting the inside corner could cause a missing triangular area and other effects. The intersection point can only be used if the join is between two lines and both lines are long enough. The `optimization' condition in `ft_stroker_inside' has been corrected; this requires the line length to be passed into various functions and stored in `FT_StrokerRec'. o Incorrect cubic curves could be generated. The angle calculations in `FT_Stroker_CubicTo' have been corrected to handle the case of the curve crossing the +/-PI direction. o If the border radius was greater than the radius of curvature of a curve, then the negative sector would end up outside (not inside) the border. This situation is now recognized and the negative sector is circumnavigated in the opposite direction. (If round line joins are being used, this code is disabled because the line join will always cover the negative sector.) o When a curve is split, the arcs may not join smoothly (especially if the curve turns sharply back on itself). Changes in direction between adjacent arcs were not handled. A round corner is now added if the deviation from one arc to the next is greater than a suitable threshold. o The current direction wasn't retained if a the outline contained a zero length lineto or a curve that was determined to be `basically a point'. This could cause a spurious join to be added. o Cubics with close control points could be mishandled. All eight cases are now distinguished correctly. Other improvements ------------------ o Borders for cubic curves could be too `flat'. FT_SMALL_CUBIC_THRESHOLD has been reduced a little to prevent this. o The handling and use of movable points has been simplified a little. o Various values are now computed only if the results are actually needed. o The directions of the outer and inner borders have been swapped, as recommended by Graham Asher. * src/base/ftstroke.c: Revised. * include/freetype/ftstroke.h: Updated.
2011-07-02 12:09:52 +02:00
/* finally, add an end point; only needed if not lineto */
/* (line_length is zero for curves) */
if ( line_length == 0 )
{
FT_Vector_From_Polar( &delta,
radius,
stroker->angle_out + rotate );
[ftstroke] Major revision. The main problems ----------------- o If FT_STROKER_LINEJOIN_BEVEL was specified, unlimited miter joins (not bevel joins) were generated. Indeed, the meanings of `miter' and `bevel' were incorrectly reversed (consistently) in both the code and comments. o The way bevel joins were constructed (whether specified explicitly, or created as a result of exceeding the miter limit) did not match what is required for stroked text in PostScript or PDF. The main fixes -------------- o The behaviour of FT_STROKER_LINEJOIN_BEVEL has been corrected. o A new line join style, FT_STROKER_LINEJOIN_MITER_FIXED, has been introduced to support PostScript and PDF miter joins. o FT_STROKER_LINEJOIN_MITER_VARIABLE has been introduced as an alias for FT_STROKER_LINEJOIN_MITER. Additionally, a variety of stroking errors have been fixed. These would cause various artifacts (including points `at infinity'), especially when stroking poor quality fonts. See http://lists.gnu.org/archive/html/freetype-devel/2011-07/msg00001.html for example documents. The FreeType stroker now produces results very similar to that produced by GhostScript and Distiller for these fonts. Other problems -------------- The following problems have been resolved: o Inside corners could be generated incorrectly. Intersecting the inside corner could cause a missing triangular area and other effects. The intersection point can only be used if the join is between two lines and both lines are long enough. The `optimization' condition in `ft_stroker_inside' has been corrected; this requires the line length to be passed into various functions and stored in `FT_StrokerRec'. o Incorrect cubic curves could be generated. The angle calculations in `FT_Stroker_CubicTo' have been corrected to handle the case of the curve crossing the +/-PI direction. o If the border radius was greater than the radius of curvature of a curve, then the negative sector would end up outside (not inside) the border. This situation is now recognized and the negative sector is circumnavigated in the opposite direction. (If round line joins are being used, this code is disabled because the line join will always cover the negative sector.) o When a curve is split, the arcs may not join smoothly (especially if the curve turns sharply back on itself). Changes in direction between adjacent arcs were not handled. A round corner is now added if the deviation from one arc to the next is greater than a suitable threshold. o The current direction wasn't retained if a the outline contained a zero length lineto or a curve that was determined to be `basically a point'. This could cause a spurious join to be added. o Cubics with close control points could be mishandled. All eight cases are now distinguished correctly. Other improvements ------------------ o Borders for cubic curves could be too `flat'. FT_SMALL_CUBIC_THRESHOLD has been reduced a little to prevent this. o The handling and use of movable points has been simplified a little. o Various values are now computed only if the results are actually needed. o The directions of the outer and inner borders have been swapped, as recommended by Graham Asher. * src/base/ftstroke.c: Revised. * include/freetype/ftstroke.h: Updated.
2011-07-02 12:09:52 +02:00
delta.x += stroker->center.x;
delta.y += stroker->center.y;
[ftstroke] Major revision. The main problems ----------------- o If FT_STROKER_LINEJOIN_BEVEL was specified, unlimited miter joins (not bevel joins) were generated. Indeed, the meanings of `miter' and `bevel' were incorrectly reversed (consistently) in both the code and comments. o The way bevel joins were constructed (whether specified explicitly, or created as a result of exceeding the miter limit) did not match what is required for stroked text in PostScript or PDF. The main fixes -------------- o The behaviour of FT_STROKER_LINEJOIN_BEVEL has been corrected. o A new line join style, FT_STROKER_LINEJOIN_MITER_FIXED, has been introduced to support PostScript and PDF miter joins. o FT_STROKER_LINEJOIN_MITER_VARIABLE has been introduced as an alias for FT_STROKER_LINEJOIN_MITER. Additionally, a variety of stroking errors have been fixed. These would cause various artifacts (including points `at infinity'), especially when stroking poor quality fonts. See http://lists.gnu.org/archive/html/freetype-devel/2011-07/msg00001.html for example documents. The FreeType stroker now produces results very similar to that produced by GhostScript and Distiller for these fonts. Other problems -------------- The following problems have been resolved: o Inside corners could be generated incorrectly. Intersecting the inside corner could cause a missing triangular area and other effects. The intersection point can only be used if the join is between two lines and both lines are long enough. The `optimization' condition in `ft_stroker_inside' has been corrected; this requires the line length to be passed into various functions and stored in `FT_StrokerRec'. o Incorrect cubic curves could be generated. The angle calculations in `FT_Stroker_CubicTo' have been corrected to handle the case of the curve crossing the +/-PI direction. o If the border radius was greater than the radius of curvature of a curve, then the negative sector would end up outside (not inside) the border. This situation is now recognized and the negative sector is circumnavigated in the opposite direction. (If round line joins are being used, this code is disabled because the line join will always cover the negative sector.) o When a curve is split, the arcs may not join smoothly (especially if the curve turns sharply back on itself). Changes in direction between adjacent arcs were not handled. A round corner is now added if the deviation from one arc to the next is greater than a suitable threshold. o The current direction wasn't retained if a the outline contained a zero length lineto or a curve that was determined to be `basically a point'. This could cause a spurious join to be added. o Cubics with close control points could be mishandled. All eight cases are now distinguished correctly. Other improvements ------------------ o Borders for cubic curves could be too `flat'. FT_SMALL_CUBIC_THRESHOLD has been reduced a little to prevent this. o The handling and use of movable points has been simplified a little. o Various values are now computed only if the results are actually needed. o The directions of the outer and inner borders have been swapped, as recommended by Graham Asher. * src/base/ftstroke.c: Revised. * include/freetype/ftstroke.h: Updated.
2011-07-02 12:09:52 +02:00
error = ft_stroke_border_lineto( border, &delta, FALSE );
}
}
}
else /* this is a miter (intersection) */
{
FT_Fixed length;
FT_Vector delta;
length = FT_DivFix( stroker->radius, thcos );
FT_Vector_From_Polar( &delta, length, phi );
delta.x += stroker->center.x;
delta.y += stroker->center.y;
2008-09-16 19:32:02 +02:00
error = ft_stroke_border_lineto( border, &delta, FALSE );
if ( error )
goto Exit;
[ftstroke] Major revision. The main problems ----------------- o If FT_STROKER_LINEJOIN_BEVEL was specified, unlimited miter joins (not bevel joins) were generated. Indeed, the meanings of `miter' and `bevel' were incorrectly reversed (consistently) in both the code and comments. o The way bevel joins were constructed (whether specified explicitly, or created as a result of exceeding the miter limit) did not match what is required for stroked text in PostScript or PDF. The main fixes -------------- o The behaviour of FT_STROKER_LINEJOIN_BEVEL has been corrected. o A new line join style, FT_STROKER_LINEJOIN_MITER_FIXED, has been introduced to support PostScript and PDF miter joins. o FT_STROKER_LINEJOIN_MITER_VARIABLE has been introduced as an alias for FT_STROKER_LINEJOIN_MITER. Additionally, a variety of stroking errors have been fixed. These would cause various artifacts (including points `at infinity'), especially when stroking poor quality fonts. See http://lists.gnu.org/archive/html/freetype-devel/2011-07/msg00001.html for example documents. The FreeType stroker now produces results very similar to that produced by GhostScript and Distiller for these fonts. Other problems -------------- The following problems have been resolved: o Inside corners could be generated incorrectly. Intersecting the inside corner could cause a missing triangular area and other effects. The intersection point can only be used if the join is between two lines and both lines are long enough. The `optimization' condition in `ft_stroker_inside' has been corrected; this requires the line length to be passed into various functions and stored in `FT_StrokerRec'. o Incorrect cubic curves could be generated. The angle calculations in `FT_Stroker_CubicTo' have been corrected to handle the case of the curve crossing the +/-PI direction. o If the border radius was greater than the radius of curvature of a curve, then the negative sector would end up outside (not inside) the border. This situation is now recognized and the negative sector is circumnavigated in the opposite direction. (If round line joins are being used, this code is disabled because the line join will always cover the negative sector.) o When a curve is split, the arcs may not join smoothly (especially if the curve turns sharply back on itself). Changes in direction between adjacent arcs were not handled. A round corner is now added if the deviation from one arc to the next is greater than a suitable threshold. o The current direction wasn't retained if a the outline contained a zero length lineto or a curve that was determined to be `basically a point'. This could cause a spurious join to be added. o Cubics with close control points could be mishandled. All eight cases are now distinguished correctly. Other improvements ------------------ o Borders for cubic curves could be too `flat'. FT_SMALL_CUBIC_THRESHOLD has been reduced a little to prevent this. o The handling and use of movable points has been simplified a little. o Various values are now computed only if the results are actually needed. o The directions of the outer and inner borders have been swapped, as recommended by Graham Asher. * src/base/ftstroke.c: Revised. * include/freetype/ftstroke.h: Updated.
2011-07-02 12:09:52 +02:00
/* now add an end point; only needed if not lineto */
/* (line_length is zero for curves) */
if ( line_length == 0 )
{
FT_Vector_From_Polar( &delta,
stroker->radius,
stroker->angle_out + rotate );
delta.x += stroker->center.x;
delta.y += stroker->center.y;
[ftstroke] Major revision. The main problems ----------------- o If FT_STROKER_LINEJOIN_BEVEL was specified, unlimited miter joins (not bevel joins) were generated. Indeed, the meanings of `miter' and `bevel' were incorrectly reversed (consistently) in both the code and comments. o The way bevel joins were constructed (whether specified explicitly, or created as a result of exceeding the miter limit) did not match what is required for stroked text in PostScript or PDF. The main fixes -------------- o The behaviour of FT_STROKER_LINEJOIN_BEVEL has been corrected. o A new line join style, FT_STROKER_LINEJOIN_MITER_FIXED, has been introduced to support PostScript and PDF miter joins. o FT_STROKER_LINEJOIN_MITER_VARIABLE has been introduced as an alias for FT_STROKER_LINEJOIN_MITER. Additionally, a variety of stroking errors have been fixed. These would cause various artifacts (including points `at infinity'), especially when stroking poor quality fonts. See http://lists.gnu.org/archive/html/freetype-devel/2011-07/msg00001.html for example documents. The FreeType stroker now produces results very similar to that produced by GhostScript and Distiller for these fonts. Other problems -------------- The following problems have been resolved: o Inside corners could be generated incorrectly. Intersecting the inside corner could cause a missing triangular area and other effects. The intersection point can only be used if the join is between two lines and both lines are long enough. The `optimization' condition in `ft_stroker_inside' has been corrected; this requires the line length to be passed into various functions and stored in `FT_StrokerRec'. o Incorrect cubic curves could be generated. The angle calculations in `FT_Stroker_CubicTo' have been corrected to handle the case of the curve crossing the +/-PI direction. o If the border radius was greater than the radius of curvature of a curve, then the negative sector would end up outside (not inside) the border. This situation is now recognized and the negative sector is circumnavigated in the opposite direction. (If round line joins are being used, this code is disabled because the line join will always cover the negative sector.) o When a curve is split, the arcs may not join smoothly (especially if the curve turns sharply back on itself). Changes in direction between adjacent arcs were not handled. A round corner is now added if the deviation from one arc to the next is greater than a suitable threshold. o The current direction wasn't retained if a the outline contained a zero length lineto or a curve that was determined to be `basically a point'. This could cause a spurious join to be added. o Cubics with close control points could be mishandled. All eight cases are now distinguished correctly. Other improvements ------------------ o Borders for cubic curves could be too `flat'. FT_SMALL_CUBIC_THRESHOLD has been reduced a little to prevent this. o The handling and use of movable points has been simplified a little. o Various values are now computed only if the results are actually needed. o The directions of the outer and inner borders have been swapped, as recommended by Graham Asher. * src/base/ftstroke.c: Revised. * include/freetype/ftstroke.h: Updated.
2011-07-02 12:09:52 +02:00
error = ft_stroke_border_lineto( border, &delta, FALSE );
}
}
}
Exit:
return error;
}
static FT_Error
[ftstroke] Major revision. The main problems ----------------- o If FT_STROKER_LINEJOIN_BEVEL was specified, unlimited miter joins (not bevel joins) were generated. Indeed, the meanings of `miter' and `bevel' were incorrectly reversed (consistently) in both the code and comments. o The way bevel joins were constructed (whether specified explicitly, or created as a result of exceeding the miter limit) did not match what is required for stroked text in PostScript or PDF. The main fixes -------------- o The behaviour of FT_STROKER_LINEJOIN_BEVEL has been corrected. o A new line join style, FT_STROKER_LINEJOIN_MITER_FIXED, has been introduced to support PostScript and PDF miter joins. o FT_STROKER_LINEJOIN_MITER_VARIABLE has been introduced as an alias for FT_STROKER_LINEJOIN_MITER. Additionally, a variety of stroking errors have been fixed. These would cause various artifacts (including points `at infinity'), especially when stroking poor quality fonts. See http://lists.gnu.org/archive/html/freetype-devel/2011-07/msg00001.html for example documents. The FreeType stroker now produces results very similar to that produced by GhostScript and Distiller for these fonts. Other problems -------------- The following problems have been resolved: o Inside corners could be generated incorrectly. Intersecting the inside corner could cause a missing triangular area and other effects. The intersection point can only be used if the join is between two lines and both lines are long enough. The `optimization' condition in `ft_stroker_inside' has been corrected; this requires the line length to be passed into various functions and stored in `FT_StrokerRec'. o Incorrect cubic curves could be generated. The angle calculations in `FT_Stroker_CubicTo' have been corrected to handle the case of the curve crossing the +/-PI direction. o If the border radius was greater than the radius of curvature of a curve, then the negative sector would end up outside (not inside) the border. This situation is now recognized and the negative sector is circumnavigated in the opposite direction. (If round line joins are being used, this code is disabled because the line join will always cover the negative sector.) o When a curve is split, the arcs may not join smoothly (especially if the curve turns sharply back on itself). Changes in direction between adjacent arcs were not handled. A round corner is now added if the deviation from one arc to the next is greater than a suitable threshold. o The current direction wasn't retained if a the outline contained a zero length lineto or a curve that was determined to be `basically a point'. This could cause a spurious join to be added. o Cubics with close control points could be mishandled. All eight cases are now distinguished correctly. Other improvements ------------------ o Borders for cubic curves could be too `flat'. FT_SMALL_CUBIC_THRESHOLD has been reduced a little to prevent this. o The handling and use of movable points has been simplified a little. o Various values are now computed only if the results are actually needed. o The directions of the outer and inner borders have been swapped, as recommended by Graham Asher. * src/base/ftstroke.c: Revised. * include/freetype/ftstroke.h: Updated.
2011-07-02 12:09:52 +02:00
ft_stroker_process_corner( FT_Stroker stroker,
FT_Fixed line_length )
{
2008-09-16 19:32:02 +02:00
FT_Error error = FT_Err_Ok;
FT_Angle turn;
FT_Int inside_side;
turn = FT_Angle_Diff( stroker->angle_in, stroker->angle_out );
/* no specific corner processing is required if the turn is 0 */
if ( turn == 0 )
goto Exit;
/* when we turn to the right, the inside side is 0 */
inside_side = 0;
/* otherwise, the inside side is 1 */
if ( turn < 0 )
inside_side = 1;
/* process the inside side */
[ftstroke] Major revision. The main problems ----------------- o If FT_STROKER_LINEJOIN_BEVEL was specified, unlimited miter joins (not bevel joins) were generated. Indeed, the meanings of `miter' and `bevel' were incorrectly reversed (consistently) in both the code and comments. o The way bevel joins were constructed (whether specified explicitly, or created as a result of exceeding the miter limit) did not match what is required for stroked text in PostScript or PDF. The main fixes -------------- o The behaviour of FT_STROKER_LINEJOIN_BEVEL has been corrected. o A new line join style, FT_STROKER_LINEJOIN_MITER_FIXED, has been introduced to support PostScript and PDF miter joins. o FT_STROKER_LINEJOIN_MITER_VARIABLE has been introduced as an alias for FT_STROKER_LINEJOIN_MITER. Additionally, a variety of stroking errors have been fixed. These would cause various artifacts (including points `at infinity'), especially when stroking poor quality fonts. See http://lists.gnu.org/archive/html/freetype-devel/2011-07/msg00001.html for example documents. The FreeType stroker now produces results very similar to that produced by GhostScript and Distiller for these fonts. Other problems -------------- The following problems have been resolved: o Inside corners could be generated incorrectly. Intersecting the inside corner could cause a missing triangular area and other effects. The intersection point can only be used if the join is between two lines and both lines are long enough. The `optimization' condition in `ft_stroker_inside' has been corrected; this requires the line length to be passed into various functions and stored in `FT_StrokerRec'. o Incorrect cubic curves could be generated. The angle calculations in `FT_Stroker_CubicTo' have been corrected to handle the case of the curve crossing the +/-PI direction. o If the border radius was greater than the radius of curvature of a curve, then the negative sector would end up outside (not inside) the border. This situation is now recognized and the negative sector is circumnavigated in the opposite direction. (If round line joins are being used, this code is disabled because the line join will always cover the negative sector.) o When a curve is split, the arcs may not join smoothly (especially if the curve turns sharply back on itself). Changes in direction between adjacent arcs were not handled. A round corner is now added if the deviation from one arc to the next is greater than a suitable threshold. o The current direction wasn't retained if a the outline contained a zero length lineto or a curve that was determined to be `basically a point'. This could cause a spurious join to be added. o Cubics with close control points could be mishandled. All eight cases are now distinguished correctly. Other improvements ------------------ o Borders for cubic curves could be too `flat'. FT_SMALL_CUBIC_THRESHOLD has been reduced a little to prevent this. o The handling and use of movable points has been simplified a little. o Various values are now computed only if the results are actually needed. o The directions of the outer and inner borders have been swapped, as recommended by Graham Asher. * src/base/ftstroke.c: Revised. * include/freetype/ftstroke.h: Updated.
2011-07-02 12:09:52 +02:00
error = ft_stroker_inside( stroker, inside_side, line_length );
if ( error )
goto Exit;
/* process the outside side */
[ftstroke] Major revision. The main problems ----------------- o If FT_STROKER_LINEJOIN_BEVEL was specified, unlimited miter joins (not bevel joins) were generated. Indeed, the meanings of `miter' and `bevel' were incorrectly reversed (consistently) in both the code and comments. o The way bevel joins were constructed (whether specified explicitly, or created as a result of exceeding the miter limit) did not match what is required for stroked text in PostScript or PDF. The main fixes -------------- o The behaviour of FT_STROKER_LINEJOIN_BEVEL has been corrected. o A new line join style, FT_STROKER_LINEJOIN_MITER_FIXED, has been introduced to support PostScript and PDF miter joins. o FT_STROKER_LINEJOIN_MITER_VARIABLE has been introduced as an alias for FT_STROKER_LINEJOIN_MITER. Additionally, a variety of stroking errors have been fixed. These would cause various artifacts (including points `at infinity'), especially when stroking poor quality fonts. See http://lists.gnu.org/archive/html/freetype-devel/2011-07/msg00001.html for example documents. The FreeType stroker now produces results very similar to that produced by GhostScript and Distiller for these fonts. Other problems -------------- The following problems have been resolved: o Inside corners could be generated incorrectly. Intersecting the inside corner could cause a missing triangular area and other effects. The intersection point can only be used if the join is between two lines and both lines are long enough. The `optimization' condition in `ft_stroker_inside' has been corrected; this requires the line length to be passed into various functions and stored in `FT_StrokerRec'. o Incorrect cubic curves could be generated. The angle calculations in `FT_Stroker_CubicTo' have been corrected to handle the case of the curve crossing the +/-PI direction. o If the border radius was greater than the radius of curvature of a curve, then the negative sector would end up outside (not inside) the border. This situation is now recognized and the negative sector is circumnavigated in the opposite direction. (If round line joins are being used, this code is disabled because the line join will always cover the negative sector.) o When a curve is split, the arcs may not join smoothly (especially if the curve turns sharply back on itself). Changes in direction between adjacent arcs were not handled. A round corner is now added if the deviation from one arc to the next is greater than a suitable threshold. o The current direction wasn't retained if a the outline contained a zero length lineto or a curve that was determined to be `basically a point'. This could cause a spurious join to be added. o Cubics with close control points could be mishandled. All eight cases are now distinguished correctly. Other improvements ------------------ o Borders for cubic curves could be too `flat'. FT_SMALL_CUBIC_THRESHOLD has been reduced a little to prevent this. o The handling and use of movable points has been simplified a little. o Various values are now computed only if the results are actually needed. o The directions of the outer and inner borders have been swapped, as recommended by Graham Asher. * src/base/ftstroke.c: Revised. * include/freetype/ftstroke.h: Updated.
2011-07-02 12:09:52 +02:00
error = ft_stroker_outside( stroker, 1 - inside_side, line_length );
Exit:
return error;
}
/* add two points to the left and right borders corresponding to the */
2008-09-16 19:32:02 +02:00
/* start of the subpath */
static FT_Error
ft_stroker_subpath_start( FT_Stroker stroker,
[ftstroke] Major revision. The main problems ----------------- o If FT_STROKER_LINEJOIN_BEVEL was specified, unlimited miter joins (not bevel joins) were generated. Indeed, the meanings of `miter' and `bevel' were incorrectly reversed (consistently) in both the code and comments. o The way bevel joins were constructed (whether specified explicitly, or created as a result of exceeding the miter limit) did not match what is required for stroked text in PostScript or PDF. The main fixes -------------- o The behaviour of FT_STROKER_LINEJOIN_BEVEL has been corrected. o A new line join style, FT_STROKER_LINEJOIN_MITER_FIXED, has been introduced to support PostScript and PDF miter joins. o FT_STROKER_LINEJOIN_MITER_VARIABLE has been introduced as an alias for FT_STROKER_LINEJOIN_MITER. Additionally, a variety of stroking errors have been fixed. These would cause various artifacts (including points `at infinity'), especially when stroking poor quality fonts. See http://lists.gnu.org/archive/html/freetype-devel/2011-07/msg00001.html for example documents. The FreeType stroker now produces results very similar to that produced by GhostScript and Distiller for these fonts. Other problems -------------- The following problems have been resolved: o Inside corners could be generated incorrectly. Intersecting the inside corner could cause a missing triangular area and other effects. The intersection point can only be used if the join is between two lines and both lines are long enough. The `optimization' condition in `ft_stroker_inside' has been corrected; this requires the line length to be passed into various functions and stored in `FT_StrokerRec'. o Incorrect cubic curves could be generated. The angle calculations in `FT_Stroker_CubicTo' have been corrected to handle the case of the curve crossing the +/-PI direction. o If the border radius was greater than the radius of curvature of a curve, then the negative sector would end up outside (not inside) the border. This situation is now recognized and the negative sector is circumnavigated in the opposite direction. (If round line joins are being used, this code is disabled because the line join will always cover the negative sector.) o When a curve is split, the arcs may not join smoothly (especially if the curve turns sharply back on itself). Changes in direction between adjacent arcs were not handled. A round corner is now added if the deviation from one arc to the next is greater than a suitable threshold. o The current direction wasn't retained if a the outline contained a zero length lineto or a curve that was determined to be `basically a point'. This could cause a spurious join to be added. o Cubics with close control points could be mishandled. All eight cases are now distinguished correctly. Other improvements ------------------ o Borders for cubic curves could be too `flat'. FT_SMALL_CUBIC_THRESHOLD has been reduced a little to prevent this. o The handling and use of movable points has been simplified a little. o Various values are now computed only if the results are actually needed. o The directions of the outer and inner borders have been swapped, as recommended by Graham Asher. * src/base/ftstroke.c: Revised. * include/freetype/ftstroke.h: Updated.
2011-07-02 12:09:52 +02:00
FT_Angle start_angle,
FT_Fixed line_length )
{
FT_Vector delta;
FT_Vector point;
FT_Error error;
FT_StrokeBorder border;
FT_Vector_From_Polar( &delta, stroker->radius,
start_angle + FT_ANGLE_PI2 );
point.x = stroker->center.x + delta.x;
point.y = stroker->center.y + delta.y;
border = stroker->borders;
error = ft_stroke_border_moveto( border, &point );
if ( error )
goto Exit;
point.x = stroker->center.x - delta.x;
point.y = stroker->center.y - delta.y;
border++;
error = ft_stroke_border_moveto( border, &point );
[ftstroke] Major revision. The main problems ----------------- o If FT_STROKER_LINEJOIN_BEVEL was specified, unlimited miter joins (not bevel joins) were generated. Indeed, the meanings of `miter' and `bevel' were incorrectly reversed (consistently) in both the code and comments. o The way bevel joins were constructed (whether specified explicitly, or created as a result of exceeding the miter limit) did not match what is required for stroked text in PostScript or PDF. The main fixes -------------- o The behaviour of FT_STROKER_LINEJOIN_BEVEL has been corrected. o A new line join style, FT_STROKER_LINEJOIN_MITER_FIXED, has been introduced to support PostScript and PDF miter joins. o FT_STROKER_LINEJOIN_MITER_VARIABLE has been introduced as an alias for FT_STROKER_LINEJOIN_MITER. Additionally, a variety of stroking errors have been fixed. These would cause various artifacts (including points `at infinity'), especially when stroking poor quality fonts. See http://lists.gnu.org/archive/html/freetype-devel/2011-07/msg00001.html for example documents. The FreeType stroker now produces results very similar to that produced by GhostScript and Distiller for these fonts. Other problems -------------- The following problems have been resolved: o Inside corners could be generated incorrectly. Intersecting the inside corner could cause a missing triangular area and other effects. The intersection point can only be used if the join is between two lines and both lines are long enough. The `optimization' condition in `ft_stroker_inside' has been corrected; this requires the line length to be passed into various functions and stored in `FT_StrokerRec'. o Incorrect cubic curves could be generated. The angle calculations in `FT_Stroker_CubicTo' have been corrected to handle the case of the curve crossing the +/-PI direction. o If the border radius was greater than the radius of curvature of a curve, then the negative sector would end up outside (not inside) the border. This situation is now recognized and the negative sector is circumnavigated in the opposite direction. (If round line joins are being used, this code is disabled because the line join will always cover the negative sector.) o When a curve is split, the arcs may not join smoothly (especially if the curve turns sharply back on itself). Changes in direction between adjacent arcs were not handled. A round corner is now added if the deviation from one arc to the next is greater than a suitable threshold. o The current direction wasn't retained if a the outline contained a zero length lineto or a curve that was determined to be `basically a point'. This could cause a spurious join to be added. o Cubics with close control points could be mishandled. All eight cases are now distinguished correctly. Other improvements ------------------ o Borders for cubic curves could be too `flat'. FT_SMALL_CUBIC_THRESHOLD has been reduced a little to prevent this. o The handling and use of movable points has been simplified a little. o Various values are now computed only if the results are actually needed. o The directions of the outer and inner borders have been swapped, as recommended by Graham Asher. * src/base/ftstroke.c: Revised. * include/freetype/ftstroke.h: Updated.
2011-07-02 12:09:52 +02:00
/* save angle, position, and line length for last join */
/* (line_length is zero for curves) */
stroker->subpath_angle = start_angle;
stroker->first_point = FALSE;
stroker->subpath_line_length = line_length;
Exit:
return error;
}
2004-12-14 00:16:59 +01:00
/* documentation is in ftstroke.h */
FT_EXPORT_DEF( FT_Error )
FT_Stroker_LineTo( FT_Stroker stroker,
FT_Vector* to )
{
2008-09-16 19:32:02 +02:00
FT_Error error = FT_Err_Ok;
FT_StrokeBorder border;
FT_Vector delta;
FT_Angle angle;
FT_Int side;
[ftstroke] Major revision. The main problems ----------------- o If FT_STROKER_LINEJOIN_BEVEL was specified, unlimited miter joins (not bevel joins) were generated. Indeed, the meanings of `miter' and `bevel' were incorrectly reversed (consistently) in both the code and comments. o The way bevel joins were constructed (whether specified explicitly, or created as a result of exceeding the miter limit) did not match what is required for stroked text in PostScript or PDF. The main fixes -------------- o The behaviour of FT_STROKER_LINEJOIN_BEVEL has been corrected. o A new line join style, FT_STROKER_LINEJOIN_MITER_FIXED, has been introduced to support PostScript and PDF miter joins. o FT_STROKER_LINEJOIN_MITER_VARIABLE has been introduced as an alias for FT_STROKER_LINEJOIN_MITER. Additionally, a variety of stroking errors have been fixed. These would cause various artifacts (including points `at infinity'), especially when stroking poor quality fonts. See http://lists.gnu.org/archive/html/freetype-devel/2011-07/msg00001.html for example documents. The FreeType stroker now produces results very similar to that produced by GhostScript and Distiller for these fonts. Other problems -------------- The following problems have been resolved: o Inside corners could be generated incorrectly. Intersecting the inside corner could cause a missing triangular area and other effects. The intersection point can only be used if the join is between two lines and both lines are long enough. The `optimization' condition in `ft_stroker_inside' has been corrected; this requires the line length to be passed into various functions and stored in `FT_StrokerRec'. o Incorrect cubic curves could be generated. The angle calculations in `FT_Stroker_CubicTo' have been corrected to handle the case of the curve crossing the +/-PI direction. o If the border radius was greater than the radius of curvature of a curve, then the negative sector would end up outside (not inside) the border. This situation is now recognized and the negative sector is circumnavigated in the opposite direction. (If round line joins are being used, this code is disabled because the line join will always cover the negative sector.) o When a curve is split, the arcs may not join smoothly (especially if the curve turns sharply back on itself). Changes in direction between adjacent arcs were not handled. A round corner is now added if the deviation from one arc to the next is greater than a suitable threshold. o The current direction wasn't retained if a the outline contained a zero length lineto or a curve that was determined to be `basically a point'. This could cause a spurious join to be added. o Cubics with close control points could be mishandled. All eight cases are now distinguished correctly. Other improvements ------------------ o Borders for cubic curves could be too `flat'. FT_SMALL_CUBIC_THRESHOLD has been reduced a little to prevent this. o The handling and use of movable points has been simplified a little. o Various values are now computed only if the results are actually needed. o The directions of the outer and inner borders have been swapped, as recommended by Graham Asher. * src/base/ftstroke.c: Revised. * include/freetype/ftstroke.h: Updated.
2011-07-02 12:09:52 +02:00
FT_Fixed line_length;
delta.x = to->x - stroker->center.x;
delta.y = to->y - stroker->center.y;
[ftstroke] Major revision. The main problems ----------------- o If FT_STROKER_LINEJOIN_BEVEL was specified, unlimited miter joins (not bevel joins) were generated. Indeed, the meanings of `miter' and `bevel' were incorrectly reversed (consistently) in both the code and comments. o The way bevel joins were constructed (whether specified explicitly, or created as a result of exceeding the miter limit) did not match what is required for stroked text in PostScript or PDF. The main fixes -------------- o The behaviour of FT_STROKER_LINEJOIN_BEVEL has been corrected. o A new line join style, FT_STROKER_LINEJOIN_MITER_FIXED, has been introduced to support PostScript and PDF miter joins. o FT_STROKER_LINEJOIN_MITER_VARIABLE has been introduced as an alias for FT_STROKER_LINEJOIN_MITER. Additionally, a variety of stroking errors have been fixed. These would cause various artifacts (including points `at infinity'), especially when stroking poor quality fonts. See http://lists.gnu.org/archive/html/freetype-devel/2011-07/msg00001.html for example documents. The FreeType stroker now produces results very similar to that produced by GhostScript and Distiller for these fonts. Other problems -------------- The following problems have been resolved: o Inside corners could be generated incorrectly. Intersecting the inside corner could cause a missing triangular area and other effects. The intersection point can only be used if the join is between two lines and both lines are long enough. The `optimization' condition in `ft_stroker_inside' has been corrected; this requires the line length to be passed into various functions and stored in `FT_StrokerRec'. o Incorrect cubic curves could be generated. The angle calculations in `FT_Stroker_CubicTo' have been corrected to handle the case of the curve crossing the +/-PI direction. o If the border radius was greater than the radius of curvature of a curve, then the negative sector would end up outside (not inside) the border. This situation is now recognized and the negative sector is circumnavigated in the opposite direction. (If round line joins are being used, this code is disabled because the line join will always cover the negative sector.) o When a curve is split, the arcs may not join smoothly (especially if the curve turns sharply back on itself). Changes in direction between adjacent arcs were not handled. A round corner is now added if the deviation from one arc to the next is greater than a suitable threshold. o The current direction wasn't retained if a the outline contained a zero length lineto or a curve that was determined to be `basically a point'. This could cause a spurious join to be added. o Cubics with close control points could be mishandled. All eight cases are now distinguished correctly. Other improvements ------------------ o Borders for cubic curves could be too `flat'. FT_SMALL_CUBIC_THRESHOLD has been reduced a little to prevent this. o The handling and use of movable points has been simplified a little. o Various values are now computed only if the results are actually needed. o The directions of the outer and inner borders have been swapped, as recommended by Graham Asher. * src/base/ftstroke.c: Revised. * include/freetype/ftstroke.h: Updated.
2011-07-02 12:09:52 +02:00
/* a zero-length lineto is a no-op; avoid creating a spurious corner */
if ( delta.x == 0 && delta.y == 0 )
goto Exit;
/* compute length of line */
line_length = FT_Vector_Length( &delta );
angle = FT_Atan2( delta.x, delta.y );
FT_Vector_From_Polar( &delta, stroker->radius, angle + FT_ANGLE_PI2 );
/* process corner if necessary */
if ( stroker->first_point )
{
/* This is the first segment of a subpath. We need to */
/* add a point to each border at their respective starting */
/* point locations. */
[ftstroke] Major revision. The main problems ----------------- o If FT_STROKER_LINEJOIN_BEVEL was specified, unlimited miter joins (not bevel joins) were generated. Indeed, the meanings of `miter' and `bevel' were incorrectly reversed (consistently) in both the code and comments. o The way bevel joins were constructed (whether specified explicitly, or created as a result of exceeding the miter limit) did not match what is required for stroked text in PostScript or PDF. The main fixes -------------- o The behaviour of FT_STROKER_LINEJOIN_BEVEL has been corrected. o A new line join style, FT_STROKER_LINEJOIN_MITER_FIXED, has been introduced to support PostScript and PDF miter joins. o FT_STROKER_LINEJOIN_MITER_VARIABLE has been introduced as an alias for FT_STROKER_LINEJOIN_MITER. Additionally, a variety of stroking errors have been fixed. These would cause various artifacts (including points `at infinity'), especially when stroking poor quality fonts. See http://lists.gnu.org/archive/html/freetype-devel/2011-07/msg00001.html for example documents. The FreeType stroker now produces results very similar to that produced by GhostScript and Distiller for these fonts. Other problems -------------- The following problems have been resolved: o Inside corners could be generated incorrectly. Intersecting the inside corner could cause a missing triangular area and other effects. The intersection point can only be used if the join is between two lines and both lines are long enough. The `optimization' condition in `ft_stroker_inside' has been corrected; this requires the line length to be passed into various functions and stored in `FT_StrokerRec'. o Incorrect cubic curves could be generated. The angle calculations in `FT_Stroker_CubicTo' have been corrected to handle the case of the curve crossing the +/-PI direction. o If the border radius was greater than the radius of curvature of a curve, then the negative sector would end up outside (not inside) the border. This situation is now recognized and the negative sector is circumnavigated in the opposite direction. (If round line joins are being used, this code is disabled because the line join will always cover the negative sector.) o When a curve is split, the arcs may not join smoothly (especially if the curve turns sharply back on itself). Changes in direction between adjacent arcs were not handled. A round corner is now added if the deviation from one arc to the next is greater than a suitable threshold. o The current direction wasn't retained if a the outline contained a zero length lineto or a curve that was determined to be `basically a point'. This could cause a spurious join to be added. o Cubics with close control points could be mishandled. All eight cases are now distinguished correctly. Other improvements ------------------ o Borders for cubic curves could be too `flat'. FT_SMALL_CUBIC_THRESHOLD has been reduced a little to prevent this. o The handling and use of movable points has been simplified a little. o Various values are now computed only if the results are actually needed. o The directions of the outer and inner borders have been swapped, as recommended by Graham Asher. * src/base/ftstroke.c: Revised. * include/freetype/ftstroke.h: Updated.
2011-07-02 12:09:52 +02:00
error = ft_stroker_subpath_start( stroker, angle, line_length );
if ( error )
goto Exit;
}
else
{
/* process the current corner */
stroker->angle_out = angle;
[ftstroke] Major revision. The main problems ----------------- o If FT_STROKER_LINEJOIN_BEVEL was specified, unlimited miter joins (not bevel joins) were generated. Indeed, the meanings of `miter' and `bevel' were incorrectly reversed (consistently) in both the code and comments. o The way bevel joins were constructed (whether specified explicitly, or created as a result of exceeding the miter limit) did not match what is required for stroked text in PostScript or PDF. The main fixes -------------- o The behaviour of FT_STROKER_LINEJOIN_BEVEL has been corrected. o A new line join style, FT_STROKER_LINEJOIN_MITER_FIXED, has been introduced to support PostScript and PDF miter joins. o FT_STROKER_LINEJOIN_MITER_VARIABLE has been introduced as an alias for FT_STROKER_LINEJOIN_MITER. Additionally, a variety of stroking errors have been fixed. These would cause various artifacts (including points `at infinity'), especially when stroking poor quality fonts. See http://lists.gnu.org/archive/html/freetype-devel/2011-07/msg00001.html for example documents. The FreeType stroker now produces results very similar to that produced by GhostScript and Distiller for these fonts. Other problems -------------- The following problems have been resolved: o Inside corners could be generated incorrectly. Intersecting the inside corner could cause a missing triangular area and other effects. The intersection point can only be used if the join is between two lines and both lines are long enough. The `optimization' condition in `ft_stroker_inside' has been corrected; this requires the line length to be passed into various functions and stored in `FT_StrokerRec'. o Incorrect cubic curves could be generated. The angle calculations in `FT_Stroker_CubicTo' have been corrected to handle the case of the curve crossing the +/-PI direction. o If the border radius was greater than the radius of curvature of a curve, then the negative sector would end up outside (not inside) the border. This situation is now recognized and the negative sector is circumnavigated in the opposite direction. (If round line joins are being used, this code is disabled because the line join will always cover the negative sector.) o When a curve is split, the arcs may not join smoothly (especially if the curve turns sharply back on itself). Changes in direction between adjacent arcs were not handled. A round corner is now added if the deviation from one arc to the next is greater than a suitable threshold. o The current direction wasn't retained if a the outline contained a zero length lineto or a curve that was determined to be `basically a point'. This could cause a spurious join to be added. o Cubics with close control points could be mishandled. All eight cases are now distinguished correctly. Other improvements ------------------ o Borders for cubic curves could be too `flat'. FT_SMALL_CUBIC_THRESHOLD has been reduced a little to prevent this. o The handling and use of movable points has been simplified a little. o Various values are now computed only if the results are actually needed. o The directions of the outer and inner borders have been swapped, as recommended by Graham Asher. * src/base/ftstroke.c: Revised. * include/freetype/ftstroke.h: Updated.
2011-07-02 12:09:52 +02:00
error = ft_stroker_process_corner( stroker, line_length );
if ( error )
goto Exit;
}
2008-09-16 19:32:02 +02:00
/* now add a line segment to both the `inside' and `outside' paths */
for ( border = stroker->borders, side = 1; side >= 0; side--, border++ )
{
FT_Vector point;
point.x = to->x + delta.x;
point.y = to->y + delta.y;
[ftstroke] Major revision. The main problems ----------------- o If FT_STROKER_LINEJOIN_BEVEL was specified, unlimited miter joins (not bevel joins) were generated. Indeed, the meanings of `miter' and `bevel' were incorrectly reversed (consistently) in both the code and comments. o The way bevel joins were constructed (whether specified explicitly, or created as a result of exceeding the miter limit) did not match what is required for stroked text in PostScript or PDF. The main fixes -------------- o The behaviour of FT_STROKER_LINEJOIN_BEVEL has been corrected. o A new line join style, FT_STROKER_LINEJOIN_MITER_FIXED, has been introduced to support PostScript and PDF miter joins. o FT_STROKER_LINEJOIN_MITER_VARIABLE has been introduced as an alias for FT_STROKER_LINEJOIN_MITER. Additionally, a variety of stroking errors have been fixed. These would cause various artifacts (including points `at infinity'), especially when stroking poor quality fonts. See http://lists.gnu.org/archive/html/freetype-devel/2011-07/msg00001.html for example documents. The FreeType stroker now produces results very similar to that produced by GhostScript and Distiller for these fonts. Other problems -------------- The following problems have been resolved: o Inside corners could be generated incorrectly. Intersecting the inside corner could cause a missing triangular area and other effects. The intersection point can only be used if the join is between two lines and both lines are long enough. The `optimization' condition in `ft_stroker_inside' has been corrected; this requires the line length to be passed into various functions and stored in `FT_StrokerRec'. o Incorrect cubic curves could be generated. The angle calculations in `FT_Stroker_CubicTo' have been corrected to handle the case of the curve crossing the +/-PI direction. o If the border radius was greater than the radius of curvature of a curve, then the negative sector would end up outside (not inside) the border. This situation is now recognized and the negative sector is circumnavigated in the opposite direction. (If round line joins are being used, this code is disabled because the line join will always cover the negative sector.) o When a curve is split, the arcs may not join smoothly (especially if the curve turns sharply back on itself). Changes in direction between adjacent arcs were not handled. A round corner is now added if the deviation from one arc to the next is greater than a suitable threshold. o The current direction wasn't retained if a the outline contained a zero length lineto or a curve that was determined to be `basically a point'. This could cause a spurious join to be added. o Cubics with close control points could be mishandled. All eight cases are now distinguished correctly. Other improvements ------------------ o Borders for cubic curves could be too `flat'. FT_SMALL_CUBIC_THRESHOLD has been reduced a little to prevent this. o The handling and use of movable points has been simplified a little. o Various values are now computed only if the results are actually needed. o The directions of the outer and inner borders have been swapped, as recommended by Graham Asher. * src/base/ftstroke.c: Revised. * include/freetype/ftstroke.h: Updated.
2011-07-02 12:09:52 +02:00
/* the ends of lineto borders are movable */
2008-09-16 19:32:02 +02:00
error = ft_stroke_border_lineto( border, &point, TRUE );
if ( error )
goto Exit;
delta.x = -delta.x;
delta.y = -delta.y;
}
[ftstroke] Major revision. The main problems ----------------- o If FT_STROKER_LINEJOIN_BEVEL was specified, unlimited miter joins (not bevel joins) were generated. Indeed, the meanings of `miter' and `bevel' were incorrectly reversed (consistently) in both the code and comments. o The way bevel joins were constructed (whether specified explicitly, or created as a result of exceeding the miter limit) did not match what is required for stroked text in PostScript or PDF. The main fixes -------------- o The behaviour of FT_STROKER_LINEJOIN_BEVEL has been corrected. o A new line join style, FT_STROKER_LINEJOIN_MITER_FIXED, has been introduced to support PostScript and PDF miter joins. o FT_STROKER_LINEJOIN_MITER_VARIABLE has been introduced as an alias for FT_STROKER_LINEJOIN_MITER. Additionally, a variety of stroking errors have been fixed. These would cause various artifacts (including points `at infinity'), especially when stroking poor quality fonts. See http://lists.gnu.org/archive/html/freetype-devel/2011-07/msg00001.html for example documents. The FreeType stroker now produces results very similar to that produced by GhostScript and Distiller for these fonts. Other problems -------------- The following problems have been resolved: o Inside corners could be generated incorrectly. Intersecting the inside corner could cause a missing triangular area and other effects. The intersection point can only be used if the join is between two lines and both lines are long enough. The `optimization' condition in `ft_stroker_inside' has been corrected; this requires the line length to be passed into various functions and stored in `FT_StrokerRec'. o Incorrect cubic curves could be generated. The angle calculations in `FT_Stroker_CubicTo' have been corrected to handle the case of the curve crossing the +/-PI direction. o If the border radius was greater than the radius of curvature of a curve, then the negative sector would end up outside (not inside) the border. This situation is now recognized and the negative sector is circumnavigated in the opposite direction. (If round line joins are being used, this code is disabled because the line join will always cover the negative sector.) o When a curve is split, the arcs may not join smoothly (especially if the curve turns sharply back on itself). Changes in direction between adjacent arcs were not handled. A round corner is now added if the deviation from one arc to the next is greater than a suitable threshold. o The current direction wasn't retained if a the outline contained a zero length lineto or a curve that was determined to be `basically a point'. This could cause a spurious join to be added. o Cubics with close control points could be mishandled. All eight cases are now distinguished correctly. Other improvements ------------------ o Borders for cubic curves could be too `flat'. FT_SMALL_CUBIC_THRESHOLD has been reduced a little to prevent this. o The handling and use of movable points has been simplified a little. o Various values are now computed only if the results are actually needed. o The directions of the outer and inner borders have been swapped, as recommended by Graham Asher. * src/base/ftstroke.c: Revised. * include/freetype/ftstroke.h: Updated.
2011-07-02 12:09:52 +02:00
stroker->angle_in = angle;
stroker->center = *to;
stroker->line_length = line_length;
Exit:
return error;
}
2004-12-14 00:16:59 +01:00
/* documentation is in ftstroke.h */
FT_EXPORT_DEF( FT_Error )
FT_Stroker_ConicTo( FT_Stroker stroker,
FT_Vector* control,
FT_Vector* to )
{
2008-09-16 19:32:02 +02:00
FT_Error error = FT_Err_Ok;
FT_Vector bez_stack[34];
FT_Vector* arc;
FT_Vector* limit = bez_stack + 30;
2008-09-16 19:32:02 +02:00
FT_Bool first_arc = TRUE;
[ftstroke] Major revision. The main problems ----------------- o If FT_STROKER_LINEJOIN_BEVEL was specified, unlimited miter joins (not bevel joins) were generated. Indeed, the meanings of `miter' and `bevel' were incorrectly reversed (consistently) in both the code and comments. o The way bevel joins were constructed (whether specified explicitly, or created as a result of exceeding the miter limit) did not match what is required for stroked text in PostScript or PDF. The main fixes -------------- o The behaviour of FT_STROKER_LINEJOIN_BEVEL has been corrected. o A new line join style, FT_STROKER_LINEJOIN_MITER_FIXED, has been introduced to support PostScript and PDF miter joins. o FT_STROKER_LINEJOIN_MITER_VARIABLE has been introduced as an alias for FT_STROKER_LINEJOIN_MITER. Additionally, a variety of stroking errors have been fixed. These would cause various artifacts (including points `at infinity'), especially when stroking poor quality fonts. See http://lists.gnu.org/archive/html/freetype-devel/2011-07/msg00001.html for example documents. The FreeType stroker now produces results very similar to that produced by GhostScript and Distiller for these fonts. Other problems -------------- The following problems have been resolved: o Inside corners could be generated incorrectly. Intersecting the inside corner could cause a missing triangular area and other effects. The intersection point can only be used if the join is between two lines and both lines are long enough. The `optimization' condition in `ft_stroker_inside' has been corrected; this requires the line length to be passed into various functions and stored in `FT_StrokerRec'. o Incorrect cubic curves could be generated. The angle calculations in `FT_Stroker_CubicTo' have been corrected to handle the case of the curve crossing the +/-PI direction. o If the border radius was greater than the radius of curvature of a curve, then the negative sector would end up outside (not inside) the border. This situation is now recognized and the negative sector is circumnavigated in the opposite direction. (If round line joins are being used, this code is disabled because the line join will always cover the negative sector.) o When a curve is split, the arcs may not join smoothly (especially if the curve turns sharply back on itself). Changes in direction between adjacent arcs were not handled. A round corner is now added if the deviation from one arc to the next is greater than a suitable threshold. o The current direction wasn't retained if a the outline contained a zero length lineto or a curve that was determined to be `basically a point'. This could cause a spurious join to be added. o Cubics with close control points could be mishandled. All eight cases are now distinguished correctly. Other improvements ------------------ o Borders for cubic curves could be too `flat'. FT_SMALL_CUBIC_THRESHOLD has been reduced a little to prevent this. o The handling and use of movable points has been simplified a little. o Various values are now computed only if the results are actually needed. o The directions of the outer and inner borders have been swapped, as recommended by Graham Asher. * src/base/ftstroke.c: Revised. * include/freetype/ftstroke.h: Updated.
2011-07-02 12:09:52 +02:00
/* if all control points are coincident, this is a no-op; */
/* avoid creating a spurious corner */
if ( FT_IS_SMALL( stroker->center.x - control->x ) &&
FT_IS_SMALL( stroker->center.y - control->y ) &&
FT_IS_SMALL( control->x - to->x ) &&
FT_IS_SMALL( control->y - to->y ) )
{
stroker->center = *to;
goto Exit;
}
arc = bez_stack;
arc[0] = *to;
arc[1] = *control;
arc[2] = stroker->center;
while ( arc >= bez_stack )
{
FT_Angle angle_in, angle_out;
[ftstroke] Major revision. The main problems ----------------- o If FT_STROKER_LINEJOIN_BEVEL was specified, unlimited miter joins (not bevel joins) were generated. Indeed, the meanings of `miter' and `bevel' were incorrectly reversed (consistently) in both the code and comments. o The way bevel joins were constructed (whether specified explicitly, or created as a result of exceeding the miter limit) did not match what is required for stroked text in PostScript or PDF. The main fixes -------------- o The behaviour of FT_STROKER_LINEJOIN_BEVEL has been corrected. o A new line join style, FT_STROKER_LINEJOIN_MITER_FIXED, has been introduced to support PostScript and PDF miter joins. o FT_STROKER_LINEJOIN_MITER_VARIABLE has been introduced as an alias for FT_STROKER_LINEJOIN_MITER. Additionally, a variety of stroking errors have been fixed. These would cause various artifacts (including points `at infinity'), especially when stroking poor quality fonts. See http://lists.gnu.org/archive/html/freetype-devel/2011-07/msg00001.html for example documents. The FreeType stroker now produces results very similar to that produced by GhostScript and Distiller for these fonts. Other problems -------------- The following problems have been resolved: o Inside corners could be generated incorrectly. Intersecting the inside corner could cause a missing triangular area and other effects. The intersection point can only be used if the join is between two lines and both lines are long enough. The `optimization' condition in `ft_stroker_inside' has been corrected; this requires the line length to be passed into various functions and stored in `FT_StrokerRec'. o Incorrect cubic curves could be generated. The angle calculations in `FT_Stroker_CubicTo' have been corrected to handle the case of the curve crossing the +/-PI direction. o If the border radius was greater than the radius of curvature of a curve, then the negative sector would end up outside (not inside) the border. This situation is now recognized and the negative sector is circumnavigated in the opposite direction. (If round line joins are being used, this code is disabled because the line join will always cover the negative sector.) o When a curve is split, the arcs may not join smoothly (especially if the curve turns sharply back on itself). Changes in direction between adjacent arcs were not handled. A round corner is now added if the deviation from one arc to the next is greater than a suitable threshold. o The current direction wasn't retained if a the outline contained a zero length lineto or a curve that was determined to be `basically a point'. This could cause a spurious join to be added. o Cubics with close control points could be mishandled. All eight cases are now distinguished correctly. Other improvements ------------------ o Borders for cubic curves could be too `flat'. FT_SMALL_CUBIC_THRESHOLD has been reduced a little to prevent this. o The handling and use of movable points has been simplified a little. o Various values are now computed only if the results are actually needed. o The directions of the outer and inner borders have been swapped, as recommended by Graham Asher. * src/base/ftstroke.c: Revised. * include/freetype/ftstroke.h: Updated.
2011-07-02 12:09:52 +02:00
/* initialize with current direction */
angle_in = angle_out = stroker->angle_in;
if ( arc < limit &&
!ft_conic_is_small_enough( arc, &angle_in, &angle_out ) )
{
[ftstroke] Major revision. The main problems ----------------- o If FT_STROKER_LINEJOIN_BEVEL was specified, unlimited miter joins (not bevel joins) were generated. Indeed, the meanings of `miter' and `bevel' were incorrectly reversed (consistently) in both the code and comments. o The way bevel joins were constructed (whether specified explicitly, or created as a result of exceeding the miter limit) did not match what is required for stroked text in PostScript or PDF. The main fixes -------------- o The behaviour of FT_STROKER_LINEJOIN_BEVEL has been corrected. o A new line join style, FT_STROKER_LINEJOIN_MITER_FIXED, has been introduced to support PostScript and PDF miter joins. o FT_STROKER_LINEJOIN_MITER_VARIABLE has been introduced as an alias for FT_STROKER_LINEJOIN_MITER. Additionally, a variety of stroking errors have been fixed. These would cause various artifacts (including points `at infinity'), especially when stroking poor quality fonts. See http://lists.gnu.org/archive/html/freetype-devel/2011-07/msg00001.html for example documents. The FreeType stroker now produces results very similar to that produced by GhostScript and Distiller for these fonts. Other problems -------------- The following problems have been resolved: o Inside corners could be generated incorrectly. Intersecting the inside corner could cause a missing triangular area and other effects. The intersection point can only be used if the join is between two lines and both lines are long enough. The `optimization' condition in `ft_stroker_inside' has been corrected; this requires the line length to be passed into various functions and stored in `FT_StrokerRec'. o Incorrect cubic curves could be generated. The angle calculations in `FT_Stroker_CubicTo' have been corrected to handle the case of the curve crossing the +/-PI direction. o If the border radius was greater than the radius of curvature of a curve, then the negative sector would end up outside (not inside) the border. This situation is now recognized and the negative sector is circumnavigated in the opposite direction. (If round line joins are being used, this code is disabled because the line join will always cover the negative sector.) o When a curve is split, the arcs may not join smoothly (especially if the curve turns sharply back on itself). Changes in direction between adjacent arcs were not handled. A round corner is now added if the deviation from one arc to the next is greater than a suitable threshold. o The current direction wasn't retained if a the outline contained a zero length lineto or a curve that was determined to be `basically a point'. This could cause a spurious join to be added. o Cubics with close control points could be mishandled. All eight cases are now distinguished correctly. Other improvements ------------------ o Borders for cubic curves could be too `flat'. FT_SMALL_CUBIC_THRESHOLD has been reduced a little to prevent this. o The handling and use of movable points has been simplified a little. o Various values are now computed only if the results are actually needed. o The directions of the outer and inner borders have been swapped, as recommended by Graham Asher. * src/base/ftstroke.c: Revised. * include/freetype/ftstroke.h: Updated.
2011-07-02 12:09:52 +02:00
if ( stroker->first_point )
stroker->angle_in = angle_in;
ft_conic_split( arc );
arc += 2;
continue;
}
if ( first_arc )
{
2008-09-16 19:32:02 +02:00
first_arc = FALSE;
/* process corner if necessary */
if ( stroker->first_point )
[ftstroke] Major revision. The main problems ----------------- o If FT_STROKER_LINEJOIN_BEVEL was specified, unlimited miter joins (not bevel joins) were generated. Indeed, the meanings of `miter' and `bevel' were incorrectly reversed (consistently) in both the code and comments. o The way bevel joins were constructed (whether specified explicitly, or created as a result of exceeding the miter limit) did not match what is required for stroked text in PostScript or PDF. The main fixes -------------- o The behaviour of FT_STROKER_LINEJOIN_BEVEL has been corrected. o A new line join style, FT_STROKER_LINEJOIN_MITER_FIXED, has been introduced to support PostScript and PDF miter joins. o FT_STROKER_LINEJOIN_MITER_VARIABLE has been introduced as an alias for FT_STROKER_LINEJOIN_MITER. Additionally, a variety of stroking errors have been fixed. These would cause various artifacts (including points `at infinity'), especially when stroking poor quality fonts. See http://lists.gnu.org/archive/html/freetype-devel/2011-07/msg00001.html for example documents. The FreeType stroker now produces results very similar to that produced by GhostScript and Distiller for these fonts. Other problems -------------- The following problems have been resolved: o Inside corners could be generated incorrectly. Intersecting the inside corner could cause a missing triangular area and other effects. The intersection point can only be used if the join is between two lines and both lines are long enough. The `optimization' condition in `ft_stroker_inside' has been corrected; this requires the line length to be passed into various functions and stored in `FT_StrokerRec'. o Incorrect cubic curves could be generated. The angle calculations in `FT_Stroker_CubicTo' have been corrected to handle the case of the curve crossing the +/-PI direction. o If the border radius was greater than the radius of curvature of a curve, then the negative sector would end up outside (not inside) the border. This situation is now recognized and the negative sector is circumnavigated in the opposite direction. (If round line joins are being used, this code is disabled because the line join will always cover the negative sector.) o When a curve is split, the arcs may not join smoothly (especially if the curve turns sharply back on itself). Changes in direction between adjacent arcs were not handled. A round corner is now added if the deviation from one arc to the next is greater than a suitable threshold. o The current direction wasn't retained if a the outline contained a zero length lineto or a curve that was determined to be `basically a point'. This could cause a spurious join to be added. o Cubics with close control points could be mishandled. All eight cases are now distinguished correctly. Other improvements ------------------ o Borders for cubic curves could be too `flat'. FT_SMALL_CUBIC_THRESHOLD has been reduced a little to prevent this. o The handling and use of movable points has been simplified a little. o Various values are now computed only if the results are actually needed. o The directions of the outer and inner borders have been swapped, as recommended by Graham Asher. * src/base/ftstroke.c: Revised. * include/freetype/ftstroke.h: Updated.
2011-07-02 12:09:52 +02:00
error = ft_stroker_subpath_start( stroker, angle_in, 0 );
else
{
[ftstroke] Major revision. The main problems ----------------- o If FT_STROKER_LINEJOIN_BEVEL was specified, unlimited miter joins (not bevel joins) were generated. Indeed, the meanings of `miter' and `bevel' were incorrectly reversed (consistently) in both the code and comments. o The way bevel joins were constructed (whether specified explicitly, or created as a result of exceeding the miter limit) did not match what is required for stroked text in PostScript or PDF. The main fixes -------------- o The behaviour of FT_STROKER_LINEJOIN_BEVEL has been corrected. o A new line join style, FT_STROKER_LINEJOIN_MITER_FIXED, has been introduced to support PostScript and PDF miter joins. o FT_STROKER_LINEJOIN_MITER_VARIABLE has been introduced as an alias for FT_STROKER_LINEJOIN_MITER. Additionally, a variety of stroking errors have been fixed. These would cause various artifacts (including points `at infinity'), especially when stroking poor quality fonts. See http://lists.gnu.org/archive/html/freetype-devel/2011-07/msg00001.html for example documents. The FreeType stroker now produces results very similar to that produced by GhostScript and Distiller for these fonts. Other problems -------------- The following problems have been resolved: o Inside corners could be generated incorrectly. Intersecting the inside corner could cause a missing triangular area and other effects. The intersection point can only be used if the join is between two lines and both lines are long enough. The `optimization' condition in `ft_stroker_inside' has been corrected; this requires the line length to be passed into various functions and stored in `FT_StrokerRec'. o Incorrect cubic curves could be generated. The angle calculations in `FT_Stroker_CubicTo' have been corrected to handle the case of the curve crossing the +/-PI direction. o If the border radius was greater than the radius of curvature of a curve, then the negative sector would end up outside (not inside) the border. This situation is now recognized and the negative sector is circumnavigated in the opposite direction. (If round line joins are being used, this code is disabled because the line join will always cover the negative sector.) o When a curve is split, the arcs may not join smoothly (especially if the curve turns sharply back on itself). Changes in direction between adjacent arcs were not handled. A round corner is now added if the deviation from one arc to the next is greater than a suitable threshold. o The current direction wasn't retained if a the outline contained a zero length lineto or a curve that was determined to be `basically a point'. This could cause a spurious join to be added. o Cubics with close control points could be mishandled. All eight cases are now distinguished correctly. Other improvements ------------------ o Borders for cubic curves could be too `flat'. FT_SMALL_CUBIC_THRESHOLD has been reduced a little to prevent this. o The handling and use of movable points has been simplified a little. o Various values are now computed only if the results are actually needed. o The directions of the outer and inner borders have been swapped, as recommended by Graham Asher. * src/base/ftstroke.c: Revised. * include/freetype/ftstroke.h: Updated.
2011-07-02 12:09:52 +02:00
stroker->angle_out = angle_in;
error = ft_stroker_process_corner( stroker, 0 );
}
}
[ftstroke] Major revision. The main problems ----------------- o If FT_STROKER_LINEJOIN_BEVEL was specified, unlimited miter joins (not bevel joins) were generated. Indeed, the meanings of `miter' and `bevel' were incorrectly reversed (consistently) in both the code and comments. o The way bevel joins were constructed (whether specified explicitly, or created as a result of exceeding the miter limit) did not match what is required for stroked text in PostScript or PDF. The main fixes -------------- o The behaviour of FT_STROKER_LINEJOIN_BEVEL has been corrected. o A new line join style, FT_STROKER_LINEJOIN_MITER_FIXED, has been introduced to support PostScript and PDF miter joins. o FT_STROKER_LINEJOIN_MITER_VARIABLE has been introduced as an alias for FT_STROKER_LINEJOIN_MITER. Additionally, a variety of stroking errors have been fixed. These would cause various artifacts (including points `at infinity'), especially when stroking poor quality fonts. See http://lists.gnu.org/archive/html/freetype-devel/2011-07/msg00001.html for example documents. The FreeType stroker now produces results very similar to that produced by GhostScript and Distiller for these fonts. Other problems -------------- The following problems have been resolved: o Inside corners could be generated incorrectly. Intersecting the inside corner could cause a missing triangular area and other effects. The intersection point can only be used if the join is between two lines and both lines are long enough. The `optimization' condition in `ft_stroker_inside' has been corrected; this requires the line length to be passed into various functions and stored in `FT_StrokerRec'. o Incorrect cubic curves could be generated. The angle calculations in `FT_Stroker_CubicTo' have been corrected to handle the case of the curve crossing the +/-PI direction. o If the border radius was greater than the radius of curvature of a curve, then the negative sector would end up outside (not inside) the border. This situation is now recognized and the negative sector is circumnavigated in the opposite direction. (If round line joins are being used, this code is disabled because the line join will always cover the negative sector.) o When a curve is split, the arcs may not join smoothly (especially if the curve turns sharply back on itself). Changes in direction between adjacent arcs were not handled. A round corner is now added if the deviation from one arc to the next is greater than a suitable threshold. o The current direction wasn't retained if a the outline contained a zero length lineto or a curve that was determined to be `basically a point'. This could cause a spurious join to be added. o Cubics with close control points could be mishandled. All eight cases are now distinguished correctly. Other improvements ------------------ o Borders for cubic curves could be too `flat'. FT_SMALL_CUBIC_THRESHOLD has been reduced a little to prevent this. o The handling and use of movable points has been simplified a little. o Various values are now computed only if the results are actually needed. o The directions of the outer and inner borders have been swapped, as recommended by Graham Asher. * src/base/ftstroke.c: Revised. * include/freetype/ftstroke.h: Updated.
2011-07-02 12:09:52 +02:00
else if ( ft_pos_abs( FT_Angle_Diff( stroker->angle_in, angle_in ) ) >
FT_SMALL_CONIC_THRESHOLD / 4 )
{
/* if the deviation from one arc to the next is too great, */
/* add a round corner */
stroker->center = arc[2];
stroker->angle_out = angle_in;
stroker->line_join = FT_STROKER_LINEJOIN_ROUND;
error = ft_stroker_process_corner( stroker, 0 );
/* reinstate line join style */
stroker->line_join = stroker->line_join_saved;
}
if ( error )
goto Exit;
/* the arc's angle is small enough; we can add it directly to each */
/* border */
{
[ftstroke] Major revision. The main problems ----------------- o If FT_STROKER_LINEJOIN_BEVEL was specified, unlimited miter joins (not bevel joins) were generated. Indeed, the meanings of `miter' and `bevel' were incorrectly reversed (consistently) in both the code and comments. o The way bevel joins were constructed (whether specified explicitly, or created as a result of exceeding the miter limit) did not match what is required for stroked text in PostScript or PDF. The main fixes -------------- o The behaviour of FT_STROKER_LINEJOIN_BEVEL has been corrected. o A new line join style, FT_STROKER_LINEJOIN_MITER_FIXED, has been introduced to support PostScript and PDF miter joins. o FT_STROKER_LINEJOIN_MITER_VARIABLE has been introduced as an alias for FT_STROKER_LINEJOIN_MITER. Additionally, a variety of stroking errors have been fixed. These would cause various artifacts (including points `at infinity'), especially when stroking poor quality fonts. See http://lists.gnu.org/archive/html/freetype-devel/2011-07/msg00001.html for example documents. The FreeType stroker now produces results very similar to that produced by GhostScript and Distiller for these fonts. Other problems -------------- The following problems have been resolved: o Inside corners could be generated incorrectly. Intersecting the inside corner could cause a missing triangular area and other effects. The intersection point can only be used if the join is between two lines and both lines are long enough. The `optimization' condition in `ft_stroker_inside' has been corrected; this requires the line length to be passed into various functions and stored in `FT_StrokerRec'. o Incorrect cubic curves could be generated. The angle calculations in `FT_Stroker_CubicTo' have been corrected to handle the case of the curve crossing the +/-PI direction. o If the border radius was greater than the radius of curvature of a curve, then the negative sector would end up outside (not inside) the border. This situation is now recognized and the negative sector is circumnavigated in the opposite direction. (If round line joins are being used, this code is disabled because the line join will always cover the negative sector.) o When a curve is split, the arcs may not join smoothly (especially if the curve turns sharply back on itself). Changes in direction between adjacent arcs were not handled. A round corner is now added if the deviation from one arc to the next is greater than a suitable threshold. o The current direction wasn't retained if a the outline contained a zero length lineto or a curve that was determined to be `basically a point'. This could cause a spurious join to be added. o Cubics with close control points could be mishandled. All eight cases are now distinguished correctly. Other improvements ------------------ o Borders for cubic curves could be too `flat'. FT_SMALL_CUBIC_THRESHOLD has been reduced a little to prevent this. o The handling and use of movable points has been simplified a little. o Various values are now computed only if the results are actually needed. o The directions of the outer and inner borders have been swapped, as recommended by Graham Asher. * src/base/ftstroke.c: Revised. * include/freetype/ftstroke.h: Updated.
2011-07-02 12:09:52 +02:00
FT_Vector ctrl, end;
FT_Angle theta, phi, rotate, alpha0 = 0;
FT_Fixed length;
FT_StrokeBorder border;
FT_Int side;
theta = FT_Angle_Diff( angle_in, angle_out ) / 2;
phi = angle_in + theta;
length = FT_DivFix( stroker->radius, FT_Cos( theta ) );
[ftstroke] Major revision. The main problems ----------------- o If FT_STROKER_LINEJOIN_BEVEL was specified, unlimited miter joins (not bevel joins) were generated. Indeed, the meanings of `miter' and `bevel' were incorrectly reversed (consistently) in both the code and comments. o The way bevel joins were constructed (whether specified explicitly, or created as a result of exceeding the miter limit) did not match what is required for stroked text in PostScript or PDF. The main fixes -------------- o The behaviour of FT_STROKER_LINEJOIN_BEVEL has been corrected. o A new line join style, FT_STROKER_LINEJOIN_MITER_FIXED, has been introduced to support PostScript and PDF miter joins. o FT_STROKER_LINEJOIN_MITER_VARIABLE has been introduced as an alias for FT_STROKER_LINEJOIN_MITER. Additionally, a variety of stroking errors have been fixed. These would cause various artifacts (including points `at infinity'), especially when stroking poor quality fonts. See http://lists.gnu.org/archive/html/freetype-devel/2011-07/msg00001.html for example documents. The FreeType stroker now produces results very similar to that produced by GhostScript and Distiller for these fonts. Other problems -------------- The following problems have been resolved: o Inside corners could be generated incorrectly. Intersecting the inside corner could cause a missing triangular area and other effects. The intersection point can only be used if the join is between two lines and both lines are long enough. The `optimization' condition in `ft_stroker_inside' has been corrected; this requires the line length to be passed into various functions and stored in `FT_StrokerRec'. o Incorrect cubic curves could be generated. The angle calculations in `FT_Stroker_CubicTo' have been corrected to handle the case of the curve crossing the +/-PI direction. o If the border radius was greater than the radius of curvature of a curve, then the negative sector would end up outside (not inside) the border. This situation is now recognized and the negative sector is circumnavigated in the opposite direction. (If round line joins are being used, this code is disabled because the line join will always cover the negative sector.) o When a curve is split, the arcs may not join smoothly (especially if the curve turns sharply back on itself). Changes in direction between adjacent arcs were not handled. A round corner is now added if the deviation from one arc to the next is greater than a suitable threshold. o The current direction wasn't retained if a the outline contained a zero length lineto or a curve that was determined to be `basically a point'. This could cause a spurious join to be added. o Cubics with close control points could be mishandled. All eight cases are now distinguished correctly. Other improvements ------------------ o Borders for cubic curves could be too `flat'. FT_SMALL_CUBIC_THRESHOLD has been reduced a little to prevent this. o The handling and use of movable points has been simplified a little. o Various values are now computed only if the results are actually needed. o The directions of the outer and inner borders have been swapped, as recommended by Graham Asher. * src/base/ftstroke.c: Revised. * include/freetype/ftstroke.h: Updated.
2011-07-02 12:09:52 +02:00
/* compute direction of original arc */
if ( stroker->handle_wide_strokes )
alpha0 = FT_Atan2( arc[0].x - arc[2].x, arc[0].y - arc[2].y );
for ( border = stroker->borders, side = 0;
side <= 1;
side++, border++ )
{
rotate = FT_SIDE_TO_ROTATE( side );
/* compute control point */
FT_Vector_From_Polar( &ctrl, length, phi + rotate );
ctrl.x += arc[1].x;
ctrl.y += arc[1].y;
/* compute end point */
FT_Vector_From_Polar( &end, stroker->radius, angle_out + rotate );
end.x += arc[0].x;
end.y += arc[0].y;
[ftstroke] Major revision. The main problems ----------------- o If FT_STROKER_LINEJOIN_BEVEL was specified, unlimited miter joins (not bevel joins) were generated. Indeed, the meanings of `miter' and `bevel' were incorrectly reversed (consistently) in both the code and comments. o The way bevel joins were constructed (whether specified explicitly, or created as a result of exceeding the miter limit) did not match what is required for stroked text in PostScript or PDF. The main fixes -------------- o The behaviour of FT_STROKER_LINEJOIN_BEVEL has been corrected. o A new line join style, FT_STROKER_LINEJOIN_MITER_FIXED, has been introduced to support PostScript and PDF miter joins. o FT_STROKER_LINEJOIN_MITER_VARIABLE has been introduced as an alias for FT_STROKER_LINEJOIN_MITER. Additionally, a variety of stroking errors have been fixed. These would cause various artifacts (including points `at infinity'), especially when stroking poor quality fonts. See http://lists.gnu.org/archive/html/freetype-devel/2011-07/msg00001.html for example documents. The FreeType stroker now produces results very similar to that produced by GhostScript and Distiller for these fonts. Other problems -------------- The following problems have been resolved: o Inside corners could be generated incorrectly. Intersecting the inside corner could cause a missing triangular area and other effects. The intersection point can only be used if the join is between two lines and both lines are long enough. The `optimization' condition in `ft_stroker_inside' has been corrected; this requires the line length to be passed into various functions and stored in `FT_StrokerRec'. o Incorrect cubic curves could be generated. The angle calculations in `FT_Stroker_CubicTo' have been corrected to handle the case of the curve crossing the +/-PI direction. o If the border radius was greater than the radius of curvature of a curve, then the negative sector would end up outside (not inside) the border. This situation is now recognized and the negative sector is circumnavigated in the opposite direction. (If round line joins are being used, this code is disabled because the line join will always cover the negative sector.) o When a curve is split, the arcs may not join smoothly (especially if the curve turns sharply back on itself). Changes in direction between adjacent arcs were not handled. A round corner is now added if the deviation from one arc to the next is greater than a suitable threshold. o The current direction wasn't retained if a the outline contained a zero length lineto or a curve that was determined to be `basically a point'. This could cause a spurious join to be added. o Cubics with close control points could be mishandled. All eight cases are now distinguished correctly. Other improvements ------------------ o Borders for cubic curves could be too `flat'. FT_SMALL_CUBIC_THRESHOLD has been reduced a little to prevent this. o The handling and use of movable points has been simplified a little. o Various values are now computed only if the results are actually needed. o The directions of the outer and inner borders have been swapped, as recommended by Graham Asher. * src/base/ftstroke.c: Revised. * include/freetype/ftstroke.h: Updated.
2011-07-02 12:09:52 +02:00
if ( stroker->handle_wide_strokes )
{
FT_Vector start;
FT_Angle alpha1;
/* determine whether the border radius is greater than the */
/* radius of curvature of the original arc */
start = border->points[border->num_points - 1];
alpha1 = FT_Atan2( end.x - start.x, end.y - start.y );
/* is the direction of the border arc opposite to */
/* that of the original arc? */
if ( ft_pos_abs( FT_Angle_Diff( alpha0, alpha1 ) ) >
FT_ANGLE_PI / 2 )
{
FT_Angle beta, gamma;
FT_Vector bvec, delta;
FT_Fixed blen, sinA, sinB, alen;
/* use the sine rule to find the intersection point */
beta = FT_Atan2( arc[2].x - start.x, arc[2].y - start.y );
gamma = FT_Atan2( arc[0].x - end.x, arc[0].y - end.y );
bvec.x = end.x - start.x;
bvec.y = end.y - start.y;
blen = FT_Vector_Length( &bvec );
sinA = ft_pos_abs( FT_Sin( alpha1 - gamma ) );
sinB = ft_pos_abs( FT_Sin( beta - gamma ) );
alen = FT_MulDiv( blen, sinA, sinB );
[ftstroke] Major revision. The main problems ----------------- o If FT_STROKER_LINEJOIN_BEVEL was specified, unlimited miter joins (not bevel joins) were generated. Indeed, the meanings of `miter' and `bevel' were incorrectly reversed (consistently) in both the code and comments. o The way bevel joins were constructed (whether specified explicitly, or created as a result of exceeding the miter limit) did not match what is required for stroked text in PostScript or PDF. The main fixes -------------- o The behaviour of FT_STROKER_LINEJOIN_BEVEL has been corrected. o A new line join style, FT_STROKER_LINEJOIN_MITER_FIXED, has been introduced to support PostScript and PDF miter joins. o FT_STROKER_LINEJOIN_MITER_VARIABLE has been introduced as an alias for FT_STROKER_LINEJOIN_MITER. Additionally, a variety of stroking errors have been fixed. These would cause various artifacts (including points `at infinity'), especially when stroking poor quality fonts. See http://lists.gnu.org/archive/html/freetype-devel/2011-07/msg00001.html for example documents. The FreeType stroker now produces results very similar to that produced by GhostScript and Distiller for these fonts. Other problems -------------- The following problems have been resolved: o Inside corners could be generated incorrectly. Intersecting the inside corner could cause a missing triangular area and other effects. The intersection point can only be used if the join is between two lines and both lines are long enough. The `optimization' condition in `ft_stroker_inside' has been corrected; this requires the line length to be passed into various functions and stored in `FT_StrokerRec'. o Incorrect cubic curves could be generated. The angle calculations in `FT_Stroker_CubicTo' have been corrected to handle the case of the curve crossing the +/-PI direction. o If the border radius was greater than the radius of curvature of a curve, then the negative sector would end up outside (not inside) the border. This situation is now recognized and the negative sector is circumnavigated in the opposite direction. (If round line joins are being used, this code is disabled because the line join will always cover the negative sector.) o When a curve is split, the arcs may not join smoothly (especially if the curve turns sharply back on itself). Changes in direction between adjacent arcs were not handled. A round corner is now added if the deviation from one arc to the next is greater than a suitable threshold. o The current direction wasn't retained if a the outline contained a zero length lineto or a curve that was determined to be `basically a point'. This could cause a spurious join to be added. o Cubics with close control points could be mishandled. All eight cases are now distinguished correctly. Other improvements ------------------ o Borders for cubic curves could be too `flat'. FT_SMALL_CUBIC_THRESHOLD has been reduced a little to prevent this. o The handling and use of movable points has been simplified a little. o Various values are now computed only if the results are actually needed. o The directions of the outer and inner borders have been swapped, as recommended by Graham Asher. * src/base/ftstroke.c: Revised. * include/freetype/ftstroke.h: Updated.
2011-07-02 12:09:52 +02:00
FT_Vector_From_Polar( &delta, alen, beta );
delta.x += start.x;
delta.y += start.y;
/* circumnavigate the negative sector backwards */
border->movable = FALSE;
error = ft_stroke_border_lineto( border, &delta, FALSE );
if ( error )
goto Exit;
error = ft_stroke_border_lineto( border, &end, FALSE );
if ( error )
goto Exit;
error = ft_stroke_border_conicto( border, &ctrl, &start );
if ( error )
goto Exit;
/* and then move to the endpoint */
error = ft_stroke_border_lineto( border, &end, FALSE );
if ( error )
goto Exit;
continue;
}
/* else fall through */
}
/* simply add an arc */
error = ft_stroke_border_conicto( border, &ctrl, &end );
if ( error )
goto Exit;
}
}
arc -= 2;
[ftstroke] Major revision. The main problems ----------------- o If FT_STROKER_LINEJOIN_BEVEL was specified, unlimited miter joins (not bevel joins) were generated. Indeed, the meanings of `miter' and `bevel' were incorrectly reversed (consistently) in both the code and comments. o The way bevel joins were constructed (whether specified explicitly, or created as a result of exceeding the miter limit) did not match what is required for stroked text in PostScript or PDF. The main fixes -------------- o The behaviour of FT_STROKER_LINEJOIN_BEVEL has been corrected. o A new line join style, FT_STROKER_LINEJOIN_MITER_FIXED, has been introduced to support PostScript and PDF miter joins. o FT_STROKER_LINEJOIN_MITER_VARIABLE has been introduced as an alias for FT_STROKER_LINEJOIN_MITER. Additionally, a variety of stroking errors have been fixed. These would cause various artifacts (including points `at infinity'), especially when stroking poor quality fonts. See http://lists.gnu.org/archive/html/freetype-devel/2011-07/msg00001.html for example documents. The FreeType stroker now produces results very similar to that produced by GhostScript and Distiller for these fonts. Other problems -------------- The following problems have been resolved: o Inside corners could be generated incorrectly. Intersecting the inside corner could cause a missing triangular area and other effects. The intersection point can only be used if the join is between two lines and both lines are long enough. The `optimization' condition in `ft_stroker_inside' has been corrected; this requires the line length to be passed into various functions and stored in `FT_StrokerRec'. o Incorrect cubic curves could be generated. The angle calculations in `FT_Stroker_CubicTo' have been corrected to handle the case of the curve crossing the +/-PI direction. o If the border radius was greater than the radius of curvature of a curve, then the negative sector would end up outside (not inside) the border. This situation is now recognized and the negative sector is circumnavigated in the opposite direction. (If round line joins are being used, this code is disabled because the line join will always cover the negative sector.) o When a curve is split, the arcs may not join smoothly (especially if the curve turns sharply back on itself). Changes in direction between adjacent arcs were not handled. A round corner is now added if the deviation from one arc to the next is greater than a suitable threshold. o The current direction wasn't retained if a the outline contained a zero length lineto or a curve that was determined to be `basically a point'. This could cause a spurious join to be added. o Cubics with close control points could be mishandled. All eight cases are now distinguished correctly. Other improvements ------------------ o Borders for cubic curves could be too `flat'. FT_SMALL_CUBIC_THRESHOLD has been reduced a little to prevent this. o The handling and use of movable points has been simplified a little. o Various values are now computed only if the results are actually needed. o The directions of the outer and inner borders have been swapped, as recommended by Graham Asher. * src/base/ftstroke.c: Revised. * include/freetype/ftstroke.h: Updated.
2011-07-02 12:09:52 +02:00
stroker->angle_in = angle_out;
}
stroker->center = *to;
Exit:
return error;
}
2004-12-14 00:16:59 +01:00
/* documentation is in ftstroke.h */
FT_EXPORT_DEF( FT_Error )
FT_Stroker_CubicTo( FT_Stroker stroker,
FT_Vector* control1,
FT_Vector* control2,
FT_Vector* to )
{
2008-09-16 19:32:02 +02:00
FT_Error error = FT_Err_Ok;
FT_Vector bez_stack[37];
FT_Vector* arc;
FT_Vector* limit = bez_stack + 32;
2008-09-16 19:32:02 +02:00
FT_Bool first_arc = TRUE;
[ftstroke] Major revision. The main problems ----------------- o If FT_STROKER_LINEJOIN_BEVEL was specified, unlimited miter joins (not bevel joins) were generated. Indeed, the meanings of `miter' and `bevel' were incorrectly reversed (consistently) in both the code and comments. o The way bevel joins were constructed (whether specified explicitly, or created as a result of exceeding the miter limit) did not match what is required for stroked text in PostScript or PDF. The main fixes -------------- o The behaviour of FT_STROKER_LINEJOIN_BEVEL has been corrected. o A new line join style, FT_STROKER_LINEJOIN_MITER_FIXED, has been introduced to support PostScript and PDF miter joins. o FT_STROKER_LINEJOIN_MITER_VARIABLE has been introduced as an alias for FT_STROKER_LINEJOIN_MITER. Additionally, a variety of stroking errors have been fixed. These would cause various artifacts (including points `at infinity'), especially when stroking poor quality fonts. See http://lists.gnu.org/archive/html/freetype-devel/2011-07/msg00001.html for example documents. The FreeType stroker now produces results very similar to that produced by GhostScript and Distiller for these fonts. Other problems -------------- The following problems have been resolved: o Inside corners could be generated incorrectly. Intersecting the inside corner could cause a missing triangular area and other effects. The intersection point can only be used if the join is between two lines and both lines are long enough. The `optimization' condition in `ft_stroker_inside' has been corrected; this requires the line length to be passed into various functions and stored in `FT_StrokerRec'. o Incorrect cubic curves could be generated. The angle calculations in `FT_Stroker_CubicTo' have been corrected to handle the case of the curve crossing the +/-PI direction. o If the border radius was greater than the radius of curvature of a curve, then the negative sector would end up outside (not inside) the border. This situation is now recognized and the negative sector is circumnavigated in the opposite direction. (If round line joins are being used, this code is disabled because the line join will always cover the negative sector.) o When a curve is split, the arcs may not join smoothly (especially if the curve turns sharply back on itself). Changes in direction between adjacent arcs were not handled. A round corner is now added if the deviation from one arc to the next is greater than a suitable threshold. o The current direction wasn't retained if a the outline contained a zero length lineto or a curve that was determined to be `basically a point'. This could cause a spurious join to be added. o Cubics with close control points could be mishandled. All eight cases are now distinguished correctly. Other improvements ------------------ o Borders for cubic curves could be too `flat'. FT_SMALL_CUBIC_THRESHOLD has been reduced a little to prevent this. o The handling and use of movable points has been simplified a little. o Various values are now computed only if the results are actually needed. o The directions of the outer and inner borders have been swapped, as recommended by Graham Asher. * src/base/ftstroke.c: Revised. * include/freetype/ftstroke.h: Updated.
2011-07-02 12:09:52 +02:00
/* if all control points are coincident, this is a no-op; */
/* avoid creating a spurious corner */
if ( FT_IS_SMALL( stroker->center.x - control1->x ) &&
FT_IS_SMALL( stroker->center.y - control1->y ) &&
FT_IS_SMALL( control1->x - control2->x ) &&
FT_IS_SMALL( control1->y - control2->y ) &&
FT_IS_SMALL( control2->x - to->x ) &&
FT_IS_SMALL( control2->y - to->y ) )
{
stroker->center = *to;
goto Exit;
}
arc = bez_stack;
arc[0] = *to;
arc[1] = *control2;
arc[2] = *control1;
arc[3] = stroker->center;
while ( arc >= bez_stack )
{
FT_Angle angle_in, angle_mid, angle_out;
[ftstroke] Major revision. The main problems ----------------- o If FT_STROKER_LINEJOIN_BEVEL was specified, unlimited miter joins (not bevel joins) were generated. Indeed, the meanings of `miter' and `bevel' were incorrectly reversed (consistently) in both the code and comments. o The way bevel joins were constructed (whether specified explicitly, or created as a result of exceeding the miter limit) did not match what is required for stroked text in PostScript or PDF. The main fixes -------------- o The behaviour of FT_STROKER_LINEJOIN_BEVEL has been corrected. o A new line join style, FT_STROKER_LINEJOIN_MITER_FIXED, has been introduced to support PostScript and PDF miter joins. o FT_STROKER_LINEJOIN_MITER_VARIABLE has been introduced as an alias for FT_STROKER_LINEJOIN_MITER. Additionally, a variety of stroking errors have been fixed. These would cause various artifacts (including points `at infinity'), especially when stroking poor quality fonts. See http://lists.gnu.org/archive/html/freetype-devel/2011-07/msg00001.html for example documents. The FreeType stroker now produces results very similar to that produced by GhostScript and Distiller for these fonts. Other problems -------------- The following problems have been resolved: o Inside corners could be generated incorrectly. Intersecting the inside corner could cause a missing triangular area and other effects. The intersection point can only be used if the join is between two lines and both lines are long enough. The `optimization' condition in `ft_stroker_inside' has been corrected; this requires the line length to be passed into various functions and stored in `FT_StrokerRec'. o Incorrect cubic curves could be generated. The angle calculations in `FT_Stroker_CubicTo' have been corrected to handle the case of the curve crossing the +/-PI direction. o If the border radius was greater than the radius of curvature of a curve, then the negative sector would end up outside (not inside) the border. This situation is now recognized and the negative sector is circumnavigated in the opposite direction. (If round line joins are being used, this code is disabled because the line join will always cover the negative sector.) o When a curve is split, the arcs may not join smoothly (especially if the curve turns sharply back on itself). Changes in direction between adjacent arcs were not handled. A round corner is now added if the deviation from one arc to the next is greater than a suitable threshold. o The current direction wasn't retained if a the outline contained a zero length lineto or a curve that was determined to be `basically a point'. This could cause a spurious join to be added. o Cubics with close control points could be mishandled. All eight cases are now distinguished correctly. Other improvements ------------------ o Borders for cubic curves could be too `flat'. FT_SMALL_CUBIC_THRESHOLD has been reduced a little to prevent this. o The handling and use of movable points has been simplified a little. o Various values are now computed only if the results are actually needed. o The directions of the outer and inner borders have been swapped, as recommended by Graham Asher. * src/base/ftstroke.c: Revised. * include/freetype/ftstroke.h: Updated.
2011-07-02 12:09:52 +02:00
/* initialize with current direction */
angle_in = angle_out = angle_mid = stroker->angle_in;
if ( arc < limit &&
!ft_cubic_is_small_enough( arc, &angle_in,
&angle_mid, &angle_out ) )
{
[ftstroke] Major revision. The main problems ----------------- o If FT_STROKER_LINEJOIN_BEVEL was specified, unlimited miter joins (not bevel joins) were generated. Indeed, the meanings of `miter' and `bevel' were incorrectly reversed (consistently) in both the code and comments. o The way bevel joins were constructed (whether specified explicitly, or created as a result of exceeding the miter limit) did not match what is required for stroked text in PostScript or PDF. The main fixes -------------- o The behaviour of FT_STROKER_LINEJOIN_BEVEL has been corrected. o A new line join style, FT_STROKER_LINEJOIN_MITER_FIXED, has been introduced to support PostScript and PDF miter joins. o FT_STROKER_LINEJOIN_MITER_VARIABLE has been introduced as an alias for FT_STROKER_LINEJOIN_MITER. Additionally, a variety of stroking errors have been fixed. These would cause various artifacts (including points `at infinity'), especially when stroking poor quality fonts. See http://lists.gnu.org/archive/html/freetype-devel/2011-07/msg00001.html for example documents. The FreeType stroker now produces results very similar to that produced by GhostScript and Distiller for these fonts. Other problems -------------- The following problems have been resolved: o Inside corners could be generated incorrectly. Intersecting the inside corner could cause a missing triangular area and other effects. The intersection point can only be used if the join is between two lines and both lines are long enough. The `optimization' condition in `ft_stroker_inside' has been corrected; this requires the line length to be passed into various functions and stored in `FT_StrokerRec'. o Incorrect cubic curves could be generated. The angle calculations in `FT_Stroker_CubicTo' have been corrected to handle the case of the curve crossing the +/-PI direction. o If the border radius was greater than the radius of curvature of a curve, then the negative sector would end up outside (not inside) the border. This situation is now recognized and the negative sector is circumnavigated in the opposite direction. (If round line joins are being used, this code is disabled because the line join will always cover the negative sector.) o When a curve is split, the arcs may not join smoothly (especially if the curve turns sharply back on itself). Changes in direction between adjacent arcs were not handled. A round corner is now added if the deviation from one arc to the next is greater than a suitable threshold. o The current direction wasn't retained if a the outline contained a zero length lineto or a curve that was determined to be `basically a point'. This could cause a spurious join to be added. o Cubics with close control points could be mishandled. All eight cases are now distinguished correctly. Other improvements ------------------ o Borders for cubic curves could be too `flat'. FT_SMALL_CUBIC_THRESHOLD has been reduced a little to prevent this. o The handling and use of movable points has been simplified a little. o Various values are now computed only if the results are actually needed. o The directions of the outer and inner borders have been swapped, as recommended by Graham Asher. * src/base/ftstroke.c: Revised. * include/freetype/ftstroke.h: Updated.
2011-07-02 12:09:52 +02:00
if ( stroker->first_point )
stroker->angle_in = angle_in;
ft_cubic_split( arc );
arc += 3;
continue;
}
if ( first_arc )
{
2008-09-16 19:32:02 +02:00
first_arc = FALSE;
/* process corner if necessary */
if ( stroker->first_point )
[ftstroke] Major revision. The main problems ----------------- o If FT_STROKER_LINEJOIN_BEVEL was specified, unlimited miter joins (not bevel joins) were generated. Indeed, the meanings of `miter' and `bevel' were incorrectly reversed (consistently) in both the code and comments. o The way bevel joins were constructed (whether specified explicitly, or created as a result of exceeding the miter limit) did not match what is required for stroked text in PostScript or PDF. The main fixes -------------- o The behaviour of FT_STROKER_LINEJOIN_BEVEL has been corrected. o A new line join style, FT_STROKER_LINEJOIN_MITER_FIXED, has been introduced to support PostScript and PDF miter joins. o FT_STROKER_LINEJOIN_MITER_VARIABLE has been introduced as an alias for FT_STROKER_LINEJOIN_MITER. Additionally, a variety of stroking errors have been fixed. These would cause various artifacts (including points `at infinity'), especially when stroking poor quality fonts. See http://lists.gnu.org/archive/html/freetype-devel/2011-07/msg00001.html for example documents. The FreeType stroker now produces results very similar to that produced by GhostScript and Distiller for these fonts. Other problems -------------- The following problems have been resolved: o Inside corners could be generated incorrectly. Intersecting the inside corner could cause a missing triangular area and other effects. The intersection point can only be used if the join is between two lines and both lines are long enough. The `optimization' condition in `ft_stroker_inside' has been corrected; this requires the line length to be passed into various functions and stored in `FT_StrokerRec'. o Incorrect cubic curves could be generated. The angle calculations in `FT_Stroker_CubicTo' have been corrected to handle the case of the curve crossing the +/-PI direction. o If the border radius was greater than the radius of curvature of a curve, then the negative sector would end up outside (not inside) the border. This situation is now recognized and the negative sector is circumnavigated in the opposite direction. (If round line joins are being used, this code is disabled because the line join will always cover the negative sector.) o When a curve is split, the arcs may not join smoothly (especially if the curve turns sharply back on itself). Changes in direction between adjacent arcs were not handled. A round corner is now added if the deviation from one arc to the next is greater than a suitable threshold. o The current direction wasn't retained if a the outline contained a zero length lineto or a curve that was determined to be `basically a point'. This could cause a spurious join to be added. o Cubics with close control points could be mishandled. All eight cases are now distinguished correctly. Other improvements ------------------ o Borders for cubic curves could be too `flat'. FT_SMALL_CUBIC_THRESHOLD has been reduced a little to prevent this. o The handling and use of movable points has been simplified a little. o Various values are now computed only if the results are actually needed. o The directions of the outer and inner borders have been swapped, as recommended by Graham Asher. * src/base/ftstroke.c: Revised. * include/freetype/ftstroke.h: Updated.
2011-07-02 12:09:52 +02:00
error = ft_stroker_subpath_start( stroker, angle_in, 0 );
else
{
[ftstroke] Major revision. The main problems ----------------- o If FT_STROKER_LINEJOIN_BEVEL was specified, unlimited miter joins (not bevel joins) were generated. Indeed, the meanings of `miter' and `bevel' were incorrectly reversed (consistently) in both the code and comments. o The way bevel joins were constructed (whether specified explicitly, or created as a result of exceeding the miter limit) did not match what is required for stroked text in PostScript or PDF. The main fixes -------------- o The behaviour of FT_STROKER_LINEJOIN_BEVEL has been corrected. o A new line join style, FT_STROKER_LINEJOIN_MITER_FIXED, has been introduced to support PostScript and PDF miter joins. o FT_STROKER_LINEJOIN_MITER_VARIABLE has been introduced as an alias for FT_STROKER_LINEJOIN_MITER. Additionally, a variety of stroking errors have been fixed. These would cause various artifacts (including points `at infinity'), especially when stroking poor quality fonts. See http://lists.gnu.org/archive/html/freetype-devel/2011-07/msg00001.html for example documents. The FreeType stroker now produces results very similar to that produced by GhostScript and Distiller for these fonts. Other problems -------------- The following problems have been resolved: o Inside corners could be generated incorrectly. Intersecting the inside corner could cause a missing triangular area and other effects. The intersection point can only be used if the join is between two lines and both lines are long enough. The `optimization' condition in `ft_stroker_inside' has been corrected; this requires the line length to be passed into various functions and stored in `FT_StrokerRec'. o Incorrect cubic curves could be generated. The angle calculations in `FT_Stroker_CubicTo' have been corrected to handle the case of the curve crossing the +/-PI direction. o If the border radius was greater than the radius of curvature of a curve, then the negative sector would end up outside (not inside) the border. This situation is now recognized and the negative sector is circumnavigated in the opposite direction. (If round line joins are being used, this code is disabled because the line join will always cover the negative sector.) o When a curve is split, the arcs may not join smoothly (especially if the curve turns sharply back on itself). Changes in direction between adjacent arcs were not handled. A round corner is now added if the deviation from one arc to the next is greater than a suitable threshold. o The current direction wasn't retained if a the outline contained a zero length lineto or a curve that was determined to be `basically a point'. This could cause a spurious join to be added. o Cubics with close control points could be mishandled. All eight cases are now distinguished correctly. Other improvements ------------------ o Borders for cubic curves could be too `flat'. FT_SMALL_CUBIC_THRESHOLD has been reduced a little to prevent this. o The handling and use of movable points has been simplified a little. o Various values are now computed only if the results are actually needed. o The directions of the outer and inner borders have been swapped, as recommended by Graham Asher. * src/base/ftstroke.c: Revised. * include/freetype/ftstroke.h: Updated.
2011-07-02 12:09:52 +02:00
stroker->angle_out = angle_in;
error = ft_stroker_process_corner( stroker, 0 );
}
[ftstroke] Major revision. The main problems ----------------- o If FT_STROKER_LINEJOIN_BEVEL was specified, unlimited miter joins (not bevel joins) were generated. Indeed, the meanings of `miter' and `bevel' were incorrectly reversed (consistently) in both the code and comments. o The way bevel joins were constructed (whether specified explicitly, or created as a result of exceeding the miter limit) did not match what is required for stroked text in PostScript or PDF. The main fixes -------------- o The behaviour of FT_STROKER_LINEJOIN_BEVEL has been corrected. o A new line join style, FT_STROKER_LINEJOIN_MITER_FIXED, has been introduced to support PostScript and PDF miter joins. o FT_STROKER_LINEJOIN_MITER_VARIABLE has been introduced as an alias for FT_STROKER_LINEJOIN_MITER. Additionally, a variety of stroking errors have been fixed. These would cause various artifacts (including points `at infinity'), especially when stroking poor quality fonts. See http://lists.gnu.org/archive/html/freetype-devel/2011-07/msg00001.html for example documents. The FreeType stroker now produces results very similar to that produced by GhostScript and Distiller for these fonts. Other problems -------------- The following problems have been resolved: o Inside corners could be generated incorrectly. Intersecting the inside corner could cause a missing triangular area and other effects. The intersection point can only be used if the join is between two lines and both lines are long enough. The `optimization' condition in `ft_stroker_inside' has been corrected; this requires the line length to be passed into various functions and stored in `FT_StrokerRec'. o Incorrect cubic curves could be generated. The angle calculations in `FT_Stroker_CubicTo' have been corrected to handle the case of the curve crossing the +/-PI direction. o If the border radius was greater than the radius of curvature of a curve, then the negative sector would end up outside (not inside) the border. This situation is now recognized and the negative sector is circumnavigated in the opposite direction. (If round line joins are being used, this code is disabled because the line join will always cover the negative sector.) o When a curve is split, the arcs may not join smoothly (especially if the curve turns sharply back on itself). Changes in direction between adjacent arcs were not handled. A round corner is now added if the deviation from one arc to the next is greater than a suitable threshold. o The current direction wasn't retained if a the outline contained a zero length lineto or a curve that was determined to be `basically a point'. This could cause a spurious join to be added. o Cubics with close control points could be mishandled. All eight cases are now distinguished correctly. Other improvements ------------------ o Borders for cubic curves could be too `flat'. FT_SMALL_CUBIC_THRESHOLD has been reduced a little to prevent this. o The handling and use of movable points has been simplified a little. o Various values are now computed only if the results are actually needed. o The directions of the outer and inner borders have been swapped, as recommended by Graham Asher. * src/base/ftstroke.c: Revised. * include/freetype/ftstroke.h: Updated.
2011-07-02 12:09:52 +02:00
}
else if ( ft_pos_abs( FT_Angle_Diff( stroker->angle_in, angle_in ) ) >
FT_SMALL_CUBIC_THRESHOLD / 4 )
{
/* if the deviation from one arc to the next is too great, */
/* add a round corner */
stroker->center = arc[3];
stroker->angle_out = angle_in;
stroker->line_join = FT_STROKER_LINEJOIN_ROUND;
error = ft_stroker_process_corner( stroker, 0 );
/* reinstate line join style */
stroker->line_join = stroker->line_join_saved;
}
[ftstroke] Major revision. The main problems ----------------- o If FT_STROKER_LINEJOIN_BEVEL was specified, unlimited miter joins (not bevel joins) were generated. Indeed, the meanings of `miter' and `bevel' were incorrectly reversed (consistently) in both the code and comments. o The way bevel joins were constructed (whether specified explicitly, or created as a result of exceeding the miter limit) did not match what is required for stroked text in PostScript or PDF. The main fixes -------------- o The behaviour of FT_STROKER_LINEJOIN_BEVEL has been corrected. o A new line join style, FT_STROKER_LINEJOIN_MITER_FIXED, has been introduced to support PostScript and PDF miter joins. o FT_STROKER_LINEJOIN_MITER_VARIABLE has been introduced as an alias for FT_STROKER_LINEJOIN_MITER. Additionally, a variety of stroking errors have been fixed. These would cause various artifacts (including points `at infinity'), especially when stroking poor quality fonts. See http://lists.gnu.org/archive/html/freetype-devel/2011-07/msg00001.html for example documents. The FreeType stroker now produces results very similar to that produced by GhostScript and Distiller for these fonts. Other problems -------------- The following problems have been resolved: o Inside corners could be generated incorrectly. Intersecting the inside corner could cause a missing triangular area and other effects. The intersection point can only be used if the join is between two lines and both lines are long enough. The `optimization' condition in `ft_stroker_inside' has been corrected; this requires the line length to be passed into various functions and stored in `FT_StrokerRec'. o Incorrect cubic curves could be generated. The angle calculations in `FT_Stroker_CubicTo' have been corrected to handle the case of the curve crossing the +/-PI direction. o If the border radius was greater than the radius of curvature of a curve, then the negative sector would end up outside (not inside) the border. This situation is now recognized and the negative sector is circumnavigated in the opposite direction. (If round line joins are being used, this code is disabled because the line join will always cover the negative sector.) o When a curve is split, the arcs may not join smoothly (especially if the curve turns sharply back on itself). Changes in direction between adjacent arcs were not handled. A round corner is now added if the deviation from one arc to the next is greater than a suitable threshold. o The current direction wasn't retained if a the outline contained a zero length lineto or a curve that was determined to be `basically a point'. This could cause a spurious join to be added. o Cubics with close control points could be mishandled. All eight cases are now distinguished correctly. Other improvements ------------------ o Borders for cubic curves could be too `flat'. FT_SMALL_CUBIC_THRESHOLD has been reduced a little to prevent this. o The handling and use of movable points has been simplified a little. o Various values are now computed only if the results are actually needed. o The directions of the outer and inner borders have been swapped, as recommended by Graham Asher. * src/base/ftstroke.c: Revised. * include/freetype/ftstroke.h: Updated.
2011-07-02 12:09:52 +02:00
if ( error )
goto Exit;
/* the arc's angle is small enough; we can add it directly to each */
/* border */
{
[ftstroke] Major revision. The main problems ----------------- o If FT_STROKER_LINEJOIN_BEVEL was specified, unlimited miter joins (not bevel joins) were generated. Indeed, the meanings of `miter' and `bevel' were incorrectly reversed (consistently) in both the code and comments. o The way bevel joins were constructed (whether specified explicitly, or created as a result of exceeding the miter limit) did not match what is required for stroked text in PostScript or PDF. The main fixes -------------- o The behaviour of FT_STROKER_LINEJOIN_BEVEL has been corrected. o A new line join style, FT_STROKER_LINEJOIN_MITER_FIXED, has been introduced to support PostScript and PDF miter joins. o FT_STROKER_LINEJOIN_MITER_VARIABLE has been introduced as an alias for FT_STROKER_LINEJOIN_MITER. Additionally, a variety of stroking errors have been fixed. These would cause various artifacts (including points `at infinity'), especially when stroking poor quality fonts. See http://lists.gnu.org/archive/html/freetype-devel/2011-07/msg00001.html for example documents. The FreeType stroker now produces results very similar to that produced by GhostScript and Distiller for these fonts. Other problems -------------- The following problems have been resolved: o Inside corners could be generated incorrectly. Intersecting the inside corner could cause a missing triangular area and other effects. The intersection point can only be used if the join is between two lines and both lines are long enough. The `optimization' condition in `ft_stroker_inside' has been corrected; this requires the line length to be passed into various functions and stored in `FT_StrokerRec'. o Incorrect cubic curves could be generated. The angle calculations in `FT_Stroker_CubicTo' have been corrected to handle the case of the curve crossing the +/-PI direction. o If the border radius was greater than the radius of curvature of a curve, then the negative sector would end up outside (not inside) the border. This situation is now recognized and the negative sector is circumnavigated in the opposite direction. (If round line joins are being used, this code is disabled because the line join will always cover the negative sector.) o When a curve is split, the arcs may not join smoothly (especially if the curve turns sharply back on itself). Changes in direction between adjacent arcs were not handled. A round corner is now added if the deviation from one arc to the next is greater than a suitable threshold. o The current direction wasn't retained if a the outline contained a zero length lineto or a curve that was determined to be `basically a point'. This could cause a spurious join to be added. o Cubics with close control points could be mishandled. All eight cases are now distinguished correctly. Other improvements ------------------ o Borders for cubic curves could be too `flat'. FT_SMALL_CUBIC_THRESHOLD has been reduced a little to prevent this. o The handling and use of movable points has been simplified a little. o Various values are now computed only if the results are actually needed. o The directions of the outer and inner borders have been swapped, as recommended by Graham Asher. * src/base/ftstroke.c: Revised. * include/freetype/ftstroke.h: Updated.
2011-07-02 12:09:52 +02:00
FT_Vector ctrl1, ctrl2, end;
FT_Angle theta1, phi1, theta2, phi2, rotate, alpha0 = 0;
FT_Fixed length1, length2;
FT_StrokeBorder border;
FT_Int side;
[ftstroke] Major revision. The main problems ----------------- o If FT_STROKER_LINEJOIN_BEVEL was specified, unlimited miter joins (not bevel joins) were generated. Indeed, the meanings of `miter' and `bevel' were incorrectly reversed (consistently) in both the code and comments. o The way bevel joins were constructed (whether specified explicitly, or created as a result of exceeding the miter limit) did not match what is required for stroked text in PostScript or PDF. The main fixes -------------- o The behaviour of FT_STROKER_LINEJOIN_BEVEL has been corrected. o A new line join style, FT_STROKER_LINEJOIN_MITER_FIXED, has been introduced to support PostScript and PDF miter joins. o FT_STROKER_LINEJOIN_MITER_VARIABLE has been introduced as an alias for FT_STROKER_LINEJOIN_MITER. Additionally, a variety of stroking errors have been fixed. These would cause various artifacts (including points `at infinity'), especially when stroking poor quality fonts. See http://lists.gnu.org/archive/html/freetype-devel/2011-07/msg00001.html for example documents. The FreeType stroker now produces results very similar to that produced by GhostScript and Distiller for these fonts. Other problems -------------- The following problems have been resolved: o Inside corners could be generated incorrectly. Intersecting the inside corner could cause a missing triangular area and other effects. The intersection point can only be used if the join is between two lines and both lines are long enough. The `optimization' condition in `ft_stroker_inside' has been corrected; this requires the line length to be passed into various functions and stored in `FT_StrokerRec'. o Incorrect cubic curves could be generated. The angle calculations in `FT_Stroker_CubicTo' have been corrected to handle the case of the curve crossing the +/-PI direction. o If the border radius was greater than the radius of curvature of a curve, then the negative sector would end up outside (not inside) the border. This situation is now recognized and the negative sector is circumnavigated in the opposite direction. (If round line joins are being used, this code is disabled because the line join will always cover the negative sector.) o When a curve is split, the arcs may not join smoothly (especially if the curve turns sharply back on itself). Changes in direction between adjacent arcs were not handled. A round corner is now added if the deviation from one arc to the next is greater than a suitable threshold. o The current direction wasn't retained if a the outline contained a zero length lineto or a curve that was determined to be `basically a point'. This could cause a spurious join to be added. o Cubics with close control points could be mishandled. All eight cases are now distinguished correctly. Other improvements ------------------ o Borders for cubic curves could be too `flat'. FT_SMALL_CUBIC_THRESHOLD has been reduced a little to prevent this. o The handling and use of movable points has been simplified a little. o Various values are now computed only if the results are actually needed. o The directions of the outer and inner borders have been swapped, as recommended by Graham Asher. * src/base/ftstroke.c: Revised. * include/freetype/ftstroke.h: Updated.
2011-07-02 12:09:52 +02:00
theta1 = FT_Angle_Diff( angle_in, angle_mid ) / 2;
theta2 = FT_Angle_Diff( angle_mid, angle_out ) / 2;
phi1 = ft_angle_mean( angle_in, angle_mid );
phi2 = ft_angle_mean( angle_mid, angle_out );
length1 = FT_DivFix( stroker->radius, FT_Cos( theta1 ) );
length2 = FT_DivFix( stroker->radius, FT_Cos( theta2 ) );
[ftstroke] Major revision. The main problems ----------------- o If FT_STROKER_LINEJOIN_BEVEL was specified, unlimited miter joins (not bevel joins) were generated. Indeed, the meanings of `miter' and `bevel' were incorrectly reversed (consistently) in both the code and comments. o The way bevel joins were constructed (whether specified explicitly, or created as a result of exceeding the miter limit) did not match what is required for stroked text in PostScript or PDF. The main fixes -------------- o The behaviour of FT_STROKER_LINEJOIN_BEVEL has been corrected. o A new line join style, FT_STROKER_LINEJOIN_MITER_FIXED, has been introduced to support PostScript and PDF miter joins. o FT_STROKER_LINEJOIN_MITER_VARIABLE has been introduced as an alias for FT_STROKER_LINEJOIN_MITER. Additionally, a variety of stroking errors have been fixed. These would cause various artifacts (including points `at infinity'), especially when stroking poor quality fonts. See http://lists.gnu.org/archive/html/freetype-devel/2011-07/msg00001.html for example documents. The FreeType stroker now produces results very similar to that produced by GhostScript and Distiller for these fonts. Other problems -------------- The following problems have been resolved: o Inside corners could be generated incorrectly. Intersecting the inside corner could cause a missing triangular area and other effects. The intersection point can only be used if the join is between two lines and both lines are long enough. The `optimization' condition in `ft_stroker_inside' has been corrected; this requires the line length to be passed into various functions and stored in `FT_StrokerRec'. o Incorrect cubic curves could be generated. The angle calculations in `FT_Stroker_CubicTo' have been corrected to handle the case of the curve crossing the +/-PI direction. o If the border radius was greater than the radius of curvature of a curve, then the negative sector would end up outside (not inside) the border. This situation is now recognized and the negative sector is circumnavigated in the opposite direction. (If round line joins are being used, this code is disabled because the line join will always cover the negative sector.) o When a curve is split, the arcs may not join smoothly (especially if the curve turns sharply back on itself). Changes in direction between adjacent arcs were not handled. A round corner is now added if the deviation from one arc to the next is greater than a suitable threshold. o The current direction wasn't retained if a the outline contained a zero length lineto or a curve that was determined to be `basically a point'. This could cause a spurious join to be added. o Cubics with close control points could be mishandled. All eight cases are now distinguished correctly. Other improvements ------------------ o Borders for cubic curves could be too `flat'. FT_SMALL_CUBIC_THRESHOLD has been reduced a little to prevent this. o The handling and use of movable points has been simplified a little. o Various values are now computed only if the results are actually needed. o The directions of the outer and inner borders have been swapped, as recommended by Graham Asher. * src/base/ftstroke.c: Revised. * include/freetype/ftstroke.h: Updated.
2011-07-02 12:09:52 +02:00
/* compute direction of original arc */
if ( stroker->handle_wide_strokes )
alpha0 = FT_Atan2( arc[0].x - arc[3].x, arc[0].y - arc[3].y );
for ( border = stroker->borders, side = 0;
side <= 1;
side++, border++ )
{
rotate = FT_SIDE_TO_ROTATE( side );
/* compute control points */
FT_Vector_From_Polar( &ctrl1, length1, phi1 + rotate );
ctrl1.x += arc[2].x;
ctrl1.y += arc[2].y;
FT_Vector_From_Polar( &ctrl2, length2, phi2 + rotate );
ctrl2.x += arc[1].x;
ctrl2.y += arc[1].y;
/* compute end point */
FT_Vector_From_Polar( &end, stroker->radius, angle_out + rotate );
end.x += arc[0].x;
end.y += arc[0].y;
[ftstroke] Major revision. The main problems ----------------- o If FT_STROKER_LINEJOIN_BEVEL was specified, unlimited miter joins (not bevel joins) were generated. Indeed, the meanings of `miter' and `bevel' were incorrectly reversed (consistently) in both the code and comments. o The way bevel joins were constructed (whether specified explicitly, or created as a result of exceeding the miter limit) did not match what is required for stroked text in PostScript or PDF. The main fixes -------------- o The behaviour of FT_STROKER_LINEJOIN_BEVEL has been corrected. o A new line join style, FT_STROKER_LINEJOIN_MITER_FIXED, has been introduced to support PostScript and PDF miter joins. o FT_STROKER_LINEJOIN_MITER_VARIABLE has been introduced as an alias for FT_STROKER_LINEJOIN_MITER. Additionally, a variety of stroking errors have been fixed. These would cause various artifacts (including points `at infinity'), especially when stroking poor quality fonts. See http://lists.gnu.org/archive/html/freetype-devel/2011-07/msg00001.html for example documents. The FreeType stroker now produces results very similar to that produced by GhostScript and Distiller for these fonts. Other problems -------------- The following problems have been resolved: o Inside corners could be generated incorrectly. Intersecting the inside corner could cause a missing triangular area and other effects. The intersection point can only be used if the join is between two lines and both lines are long enough. The `optimization' condition in `ft_stroker_inside' has been corrected; this requires the line length to be passed into various functions and stored in `FT_StrokerRec'. o Incorrect cubic curves could be generated. The angle calculations in `FT_Stroker_CubicTo' have been corrected to handle the case of the curve crossing the +/-PI direction. o If the border radius was greater than the radius of curvature of a curve, then the negative sector would end up outside (not inside) the border. This situation is now recognized and the negative sector is circumnavigated in the opposite direction. (If round line joins are being used, this code is disabled because the line join will always cover the negative sector.) o When a curve is split, the arcs may not join smoothly (especially if the curve turns sharply back on itself). Changes in direction between adjacent arcs were not handled. A round corner is now added if the deviation from one arc to the next is greater than a suitable threshold. o The current direction wasn't retained if a the outline contained a zero length lineto or a curve that was determined to be `basically a point'. This could cause a spurious join to be added. o Cubics with close control points could be mishandled. All eight cases are now distinguished correctly. Other improvements ------------------ o Borders for cubic curves could be too `flat'. FT_SMALL_CUBIC_THRESHOLD has been reduced a little to prevent this. o The handling and use of movable points has been simplified a little. o Various values are now computed only if the results are actually needed. o The directions of the outer and inner borders have been swapped, as recommended by Graham Asher. * src/base/ftstroke.c: Revised. * include/freetype/ftstroke.h: Updated.
2011-07-02 12:09:52 +02:00
if ( stroker->handle_wide_strokes )
{
FT_Vector start;
FT_Angle alpha1;
/* determine whether the border radius is greater than the */
/* radius of curvature of the original arc */
start = border->points[border->num_points - 1];
alpha1 = FT_Atan2( end.x - start.x, end.y - start.y );
/* is the direction of the border arc opposite to */
/* that of the original arc? */
if ( ft_pos_abs( FT_Angle_Diff( alpha0, alpha1 ) ) >
FT_ANGLE_PI / 2 )
{
FT_Angle beta, gamma;
FT_Vector bvec, delta;
FT_Fixed blen, sinA, sinB, alen;
/* use the sine rule to find the intersection point */
beta = FT_Atan2( arc[3].x - start.x, arc[3].y - start.y );
gamma = FT_Atan2( arc[0].x - end.x, arc[0].y - end.y );
bvec.x = end.x - start.x;
bvec.y = end.y - start.y;
blen = FT_Vector_Length( &bvec );
sinA = ft_pos_abs( FT_Sin( alpha1 - gamma ) );
sinB = ft_pos_abs( FT_Sin( beta - gamma ) );
alen = FT_MulDiv( blen, sinA, sinB );
[ftstroke] Major revision. The main problems ----------------- o If FT_STROKER_LINEJOIN_BEVEL was specified, unlimited miter joins (not bevel joins) were generated. Indeed, the meanings of `miter' and `bevel' were incorrectly reversed (consistently) in both the code and comments. o The way bevel joins were constructed (whether specified explicitly, or created as a result of exceeding the miter limit) did not match what is required for stroked text in PostScript or PDF. The main fixes -------------- o The behaviour of FT_STROKER_LINEJOIN_BEVEL has been corrected. o A new line join style, FT_STROKER_LINEJOIN_MITER_FIXED, has been introduced to support PostScript and PDF miter joins. o FT_STROKER_LINEJOIN_MITER_VARIABLE has been introduced as an alias for FT_STROKER_LINEJOIN_MITER. Additionally, a variety of stroking errors have been fixed. These would cause various artifacts (including points `at infinity'), especially when stroking poor quality fonts. See http://lists.gnu.org/archive/html/freetype-devel/2011-07/msg00001.html for example documents. The FreeType stroker now produces results very similar to that produced by GhostScript and Distiller for these fonts. Other problems -------------- The following problems have been resolved: o Inside corners could be generated incorrectly. Intersecting the inside corner could cause a missing triangular area and other effects. The intersection point can only be used if the join is between two lines and both lines are long enough. The `optimization' condition in `ft_stroker_inside' has been corrected; this requires the line length to be passed into various functions and stored in `FT_StrokerRec'. o Incorrect cubic curves could be generated. The angle calculations in `FT_Stroker_CubicTo' have been corrected to handle the case of the curve crossing the +/-PI direction. o If the border radius was greater than the radius of curvature of a curve, then the negative sector would end up outside (not inside) the border. This situation is now recognized and the negative sector is circumnavigated in the opposite direction. (If round line joins are being used, this code is disabled because the line join will always cover the negative sector.) o When a curve is split, the arcs may not join smoothly (especially if the curve turns sharply back on itself). Changes in direction between adjacent arcs were not handled. A round corner is now added if the deviation from one arc to the next is greater than a suitable threshold. o The current direction wasn't retained if a the outline contained a zero length lineto or a curve that was determined to be `basically a point'. This could cause a spurious join to be added. o Cubics with close control points could be mishandled. All eight cases are now distinguished correctly. Other improvements ------------------ o Borders for cubic curves could be too `flat'. FT_SMALL_CUBIC_THRESHOLD has been reduced a little to prevent this. o The handling and use of movable points has been simplified a little. o Various values are now computed only if the results are actually needed. o The directions of the outer and inner borders have been swapped, as recommended by Graham Asher. * src/base/ftstroke.c: Revised. * include/freetype/ftstroke.h: Updated.
2011-07-02 12:09:52 +02:00
FT_Vector_From_Polar( &delta, alen, beta );
delta.x += start.x;
delta.y += start.y;
/* circumnavigate the negative sector backwards */
border->movable = FALSE;
error = ft_stroke_border_lineto( border, &delta, FALSE );
if ( error )
goto Exit;
error = ft_stroke_border_lineto( border, &end, FALSE );
if ( error )
goto Exit;
error = ft_stroke_border_cubicto( border,
&ctrl2,
&ctrl1,
&start );
if ( error )
goto Exit;
/* and then move to the endpoint */
error = ft_stroke_border_lineto( border, &end, FALSE );
if ( error )
goto Exit;
continue;
}
/* else fall through */
}
/* simply add an arc */
error = ft_stroke_border_cubicto( border, &ctrl1, &ctrl2, &end );
if ( error )
goto Exit;
}
}
arc -= 3;
[ftstroke] Major revision. The main problems ----------------- o If FT_STROKER_LINEJOIN_BEVEL was specified, unlimited miter joins (not bevel joins) were generated. Indeed, the meanings of `miter' and `bevel' were incorrectly reversed (consistently) in both the code and comments. o The way bevel joins were constructed (whether specified explicitly, or created as a result of exceeding the miter limit) did not match what is required for stroked text in PostScript or PDF. The main fixes -------------- o The behaviour of FT_STROKER_LINEJOIN_BEVEL has been corrected. o A new line join style, FT_STROKER_LINEJOIN_MITER_FIXED, has been introduced to support PostScript and PDF miter joins. o FT_STROKER_LINEJOIN_MITER_VARIABLE has been introduced as an alias for FT_STROKER_LINEJOIN_MITER. Additionally, a variety of stroking errors have been fixed. These would cause various artifacts (including points `at infinity'), especially when stroking poor quality fonts. See http://lists.gnu.org/archive/html/freetype-devel/2011-07/msg00001.html for example documents. The FreeType stroker now produces results very similar to that produced by GhostScript and Distiller for these fonts. Other problems -------------- The following problems have been resolved: o Inside corners could be generated incorrectly. Intersecting the inside corner could cause a missing triangular area and other effects. The intersection point can only be used if the join is between two lines and both lines are long enough. The `optimization' condition in `ft_stroker_inside' has been corrected; this requires the line length to be passed into various functions and stored in `FT_StrokerRec'. o Incorrect cubic curves could be generated. The angle calculations in `FT_Stroker_CubicTo' have been corrected to handle the case of the curve crossing the +/-PI direction. o If the border radius was greater than the radius of curvature of a curve, then the negative sector would end up outside (not inside) the border. This situation is now recognized and the negative sector is circumnavigated in the opposite direction. (If round line joins are being used, this code is disabled because the line join will always cover the negative sector.) o When a curve is split, the arcs may not join smoothly (especially if the curve turns sharply back on itself). Changes in direction between adjacent arcs were not handled. A round corner is now added if the deviation from one arc to the next is greater than a suitable threshold. o The current direction wasn't retained if a the outline contained a zero length lineto or a curve that was determined to be `basically a point'. This could cause a spurious join to be added. o Cubics with close control points could be mishandled. All eight cases are now distinguished correctly. Other improvements ------------------ o Borders for cubic curves could be too `flat'. FT_SMALL_CUBIC_THRESHOLD has been reduced a little to prevent this. o The handling and use of movable points has been simplified a little. o Various values are now computed only if the results are actually needed. o The directions of the outer and inner borders have been swapped, as recommended by Graham Asher. * src/base/ftstroke.c: Revised. * include/freetype/ftstroke.h: Updated.
2011-07-02 12:09:52 +02:00
stroker->angle_in = angle_out;
}
stroker->center = *to;
Exit:
return error;
}
2004-12-14 00:16:59 +01:00
/* documentation is in ftstroke.h */
FT_EXPORT_DEF( FT_Error )
FT_Stroker_BeginSubPath( FT_Stroker stroker,
FT_Vector* to,
FT_Bool open )
{
/* We cannot process the first point, because there is not enough */
/* information regarding its corner/cap. The latter will be processed */
2008-09-16 19:32:02 +02:00
/* in the `FT_Stroker_EndSubPath' routine. */
/* */
2008-09-16 19:32:02 +02:00
stroker->first_point = TRUE;
stroker->center = *to;
stroker->subpath_open = open;
[ftstroke] Major revision. The main problems ----------------- o If FT_STROKER_LINEJOIN_BEVEL was specified, unlimited miter joins (not bevel joins) were generated. Indeed, the meanings of `miter' and `bevel' were incorrectly reversed (consistently) in both the code and comments. o The way bevel joins were constructed (whether specified explicitly, or created as a result of exceeding the miter limit) did not match what is required for stroked text in PostScript or PDF. The main fixes -------------- o The behaviour of FT_STROKER_LINEJOIN_BEVEL has been corrected. o A new line join style, FT_STROKER_LINEJOIN_MITER_FIXED, has been introduced to support PostScript and PDF miter joins. o FT_STROKER_LINEJOIN_MITER_VARIABLE has been introduced as an alias for FT_STROKER_LINEJOIN_MITER. Additionally, a variety of stroking errors have been fixed. These would cause various artifacts (including points `at infinity'), especially when stroking poor quality fonts. See http://lists.gnu.org/archive/html/freetype-devel/2011-07/msg00001.html for example documents. The FreeType stroker now produces results very similar to that produced by GhostScript and Distiller for these fonts. Other problems -------------- The following problems have been resolved: o Inside corners could be generated incorrectly. Intersecting the inside corner could cause a missing triangular area and other effects. The intersection point can only be used if the join is between two lines and both lines are long enough. The `optimization' condition in `ft_stroker_inside' has been corrected; this requires the line length to be passed into various functions and stored in `FT_StrokerRec'. o Incorrect cubic curves could be generated. The angle calculations in `FT_Stroker_CubicTo' have been corrected to handle the case of the curve crossing the +/-PI direction. o If the border radius was greater than the radius of curvature of a curve, then the negative sector would end up outside (not inside) the border. This situation is now recognized and the negative sector is circumnavigated in the opposite direction. (If round line joins are being used, this code is disabled because the line join will always cover the negative sector.) o When a curve is split, the arcs may not join smoothly (especially if the curve turns sharply back on itself). Changes in direction between adjacent arcs were not handled. A round corner is now added if the deviation from one arc to the next is greater than a suitable threshold. o The current direction wasn't retained if a the outline contained a zero length lineto or a curve that was determined to be `basically a point'. This could cause a spurious join to be added. o Cubics with close control points could be mishandled. All eight cases are now distinguished correctly. Other improvements ------------------ o Borders for cubic curves could be too `flat'. FT_SMALL_CUBIC_THRESHOLD has been reduced a little to prevent this. o The handling and use of movable points has been simplified a little. o Various values are now computed only if the results are actually needed. o The directions of the outer and inner borders have been swapped, as recommended by Graham Asher. * src/base/ftstroke.c: Revised. * include/freetype/ftstroke.h: Updated.
2011-07-02 12:09:52 +02:00
/* Determine if we need to check whether the border radius is greater */
/* than the radius of curvature of a curve, to handle this case */
/* specially. This is only required if bevel joins or butt caps may */
/* be created, because round & miter joins and round & square caps */
/* cover the negative sector created with wide strokes. */
stroker->handle_wide_strokes =
FT_BOOL( stroker->line_join != FT_STROKER_LINEJOIN_ROUND ||
( stroker->subpath_open &&
stroker->line_cap == FT_STROKER_LINECAP_BUTT ) );
2008-09-16 19:32:02 +02:00
/* record the subpath start point for each border */
stroker->subpath_start = *to;
2008-09-16 19:32:02 +02:00
[ftstroke] Major revision. The main problems ----------------- o If FT_STROKER_LINEJOIN_BEVEL was specified, unlimited miter joins (not bevel joins) were generated. Indeed, the meanings of `miter' and `bevel' were incorrectly reversed (consistently) in both the code and comments. o The way bevel joins were constructed (whether specified explicitly, or created as a result of exceeding the miter limit) did not match what is required for stroked text in PostScript or PDF. The main fixes -------------- o The behaviour of FT_STROKER_LINEJOIN_BEVEL has been corrected. o A new line join style, FT_STROKER_LINEJOIN_MITER_FIXED, has been introduced to support PostScript and PDF miter joins. o FT_STROKER_LINEJOIN_MITER_VARIABLE has been introduced as an alias for FT_STROKER_LINEJOIN_MITER. Additionally, a variety of stroking errors have been fixed. These would cause various artifacts (including points `at infinity'), especially when stroking poor quality fonts. See http://lists.gnu.org/archive/html/freetype-devel/2011-07/msg00001.html for example documents. The FreeType stroker now produces results very similar to that produced by GhostScript and Distiller for these fonts. Other problems -------------- The following problems have been resolved: o Inside corners could be generated incorrectly. Intersecting the inside corner could cause a missing triangular area and other effects. The intersection point can only be used if the join is between two lines and both lines are long enough. The `optimization' condition in `ft_stroker_inside' has been corrected; this requires the line length to be passed into various functions and stored in `FT_StrokerRec'. o Incorrect cubic curves could be generated. The angle calculations in `FT_Stroker_CubicTo' have been corrected to handle the case of the curve crossing the +/-PI direction. o If the border radius was greater than the radius of curvature of a curve, then the negative sector would end up outside (not inside) the border. This situation is now recognized and the negative sector is circumnavigated in the opposite direction. (If round line joins are being used, this code is disabled because the line join will always cover the negative sector.) o When a curve is split, the arcs may not join smoothly (especially if the curve turns sharply back on itself). Changes in direction between adjacent arcs were not handled. A round corner is now added if the deviation from one arc to the next is greater than a suitable threshold. o The current direction wasn't retained if a the outline contained a zero length lineto or a curve that was determined to be `basically a point'. This could cause a spurious join to be added. o Cubics with close control points could be mishandled. All eight cases are now distinguished correctly. Other improvements ------------------ o Borders for cubic curves could be too `flat'. FT_SMALL_CUBIC_THRESHOLD has been reduced a little to prevent this. o The handling and use of movable points has been simplified a little. o Various values are now computed only if the results are actually needed. o The directions of the outer and inner borders have been swapped, as recommended by Graham Asher. * src/base/ftstroke.c: Revised. * include/freetype/ftstroke.h: Updated.
2011-07-02 12:09:52 +02:00
stroker->angle_in = 0;
2008-09-16 19:32:02 +02:00
return FT_Err_Ok;
}
static FT_Error
ft_stroker_add_reverse_left( FT_Stroker stroker,
FT_Bool open )
{
2008-09-16 19:32:02 +02:00
FT_StrokeBorder right = stroker->borders + 0;
FT_StrokeBorder left = stroker->borders + 1;
FT_Int new_points;
2008-09-16 19:32:02 +02:00
FT_Error error = FT_Err_Ok;
FT_ASSERT( left->start >= 0 );
new_points = left->num_points - left->start;
if ( new_points > 0 )
{
error = ft_stroke_border_grow( right, (FT_UInt)new_points );
if ( error )
goto Exit;
{
FT_Vector* dst_point = right->points + right->num_points;
FT_Byte* dst_tag = right->tags + right->num_points;
FT_Vector* src_point = left->points + left->num_points - 1;
FT_Byte* src_tag = left->tags + left->num_points - 1;
[ftstroke] Major revision. The main problems ----------------- o If FT_STROKER_LINEJOIN_BEVEL was specified, unlimited miter joins (not bevel joins) were generated. Indeed, the meanings of `miter' and `bevel' were incorrectly reversed (consistently) in both the code and comments. o The way bevel joins were constructed (whether specified explicitly, or created as a result of exceeding the miter limit) did not match what is required for stroked text in PostScript or PDF. The main fixes -------------- o The behaviour of FT_STROKER_LINEJOIN_BEVEL has been corrected. o A new line join style, FT_STROKER_LINEJOIN_MITER_FIXED, has been introduced to support PostScript and PDF miter joins. o FT_STROKER_LINEJOIN_MITER_VARIABLE has been introduced as an alias for FT_STROKER_LINEJOIN_MITER. Additionally, a variety of stroking errors have been fixed. These would cause various artifacts (including points `at infinity'), especially when stroking poor quality fonts. See http://lists.gnu.org/archive/html/freetype-devel/2011-07/msg00001.html for example documents. The FreeType stroker now produces results very similar to that produced by GhostScript and Distiller for these fonts. Other problems -------------- The following problems have been resolved: o Inside corners could be generated incorrectly. Intersecting the inside corner could cause a missing triangular area and other effects. The intersection point can only be used if the join is between two lines and both lines are long enough. The `optimization' condition in `ft_stroker_inside' has been corrected; this requires the line length to be passed into various functions and stored in `FT_StrokerRec'. o Incorrect cubic curves could be generated. The angle calculations in `FT_Stroker_CubicTo' have been corrected to handle the case of the curve crossing the +/-PI direction. o If the border radius was greater than the radius of curvature of a curve, then the negative sector would end up outside (not inside) the border. This situation is now recognized and the negative sector is circumnavigated in the opposite direction. (If round line joins are being used, this code is disabled because the line join will always cover the negative sector.) o When a curve is split, the arcs may not join smoothly (especially if the curve turns sharply back on itself). Changes in direction between adjacent arcs were not handled. A round corner is now added if the deviation from one arc to the next is greater than a suitable threshold. o The current direction wasn't retained if a the outline contained a zero length lineto or a curve that was determined to be `basically a point'. This could cause a spurious join to be added. o Cubics with close control points could be mishandled. All eight cases are now distinguished correctly. Other improvements ------------------ o Borders for cubic curves could be too `flat'. FT_SMALL_CUBIC_THRESHOLD has been reduced a little to prevent this. o The handling and use of movable points has been simplified a little. o Various values are now computed only if the results are actually needed. o The directions of the outer and inner borders have been swapped, as recommended by Graham Asher. * src/base/ftstroke.c: Revised. * include/freetype/ftstroke.h: Updated.
2011-07-02 12:09:52 +02:00
while ( src_point >= left->points + left->start )
{
*dst_point = *src_point;
*dst_tag = *src_tag;
if ( open )
dst_tag[0] &= ~FT_STROKE_TAG_BEGIN_END;
else
{
[ftstroke] Major revision. The main problems ----------------- o If FT_STROKER_LINEJOIN_BEVEL was specified, unlimited miter joins (not bevel joins) were generated. Indeed, the meanings of `miter' and `bevel' were incorrectly reversed (consistently) in both the code and comments. o The way bevel joins were constructed (whether specified explicitly, or created as a result of exceeding the miter limit) did not match what is required for stroked text in PostScript or PDF. The main fixes -------------- o The behaviour of FT_STROKER_LINEJOIN_BEVEL has been corrected. o A new line join style, FT_STROKER_LINEJOIN_MITER_FIXED, has been introduced to support PostScript and PDF miter joins. o FT_STROKER_LINEJOIN_MITER_VARIABLE has been introduced as an alias for FT_STROKER_LINEJOIN_MITER. Additionally, a variety of stroking errors have been fixed. These would cause various artifacts (including points `at infinity'), especially when stroking poor quality fonts. See http://lists.gnu.org/archive/html/freetype-devel/2011-07/msg00001.html for example documents. The FreeType stroker now produces results very similar to that produced by GhostScript and Distiller for these fonts. Other problems -------------- The following problems have been resolved: o Inside corners could be generated incorrectly. Intersecting the inside corner could cause a missing triangular area and other effects. The intersection point can only be used if the join is between two lines and both lines are long enough. The `optimization' condition in `ft_stroker_inside' has been corrected; this requires the line length to be passed into various functions and stored in `FT_StrokerRec'. o Incorrect cubic curves could be generated. The angle calculations in `FT_Stroker_CubicTo' have been corrected to handle the case of the curve crossing the +/-PI direction. o If the border radius was greater than the radius of curvature of a curve, then the negative sector would end up outside (not inside) the border. This situation is now recognized and the negative sector is circumnavigated in the opposite direction. (If round line joins are being used, this code is disabled because the line join will always cover the negative sector.) o When a curve is split, the arcs may not join smoothly (especially if the curve turns sharply back on itself). Changes in direction between adjacent arcs were not handled. A round corner is now added if the deviation from one arc to the next is greater than a suitable threshold. o The current direction wasn't retained if a the outline contained a zero length lineto or a curve that was determined to be `basically a point'. This could cause a spurious join to be added. o Cubics with close control points could be mishandled. All eight cases are now distinguished correctly. Other improvements ------------------ o Borders for cubic curves could be too `flat'. FT_SMALL_CUBIC_THRESHOLD has been reduced a little to prevent this. o The handling and use of movable points has been simplified a little. o Various values are now computed only if the results are actually needed. o The directions of the outer and inner borders have been swapped, as recommended by Graham Asher. * src/base/ftstroke.c: Revised. * include/freetype/ftstroke.h: Updated.
2011-07-02 12:09:52 +02:00
FT_Byte ttag =
(FT_Byte)( dst_tag[0] & FT_STROKE_TAG_BEGIN_END );
/* switch begin/end tags if necessary */
if ( ttag == FT_STROKE_TAG_BEGIN ||
ttag == FT_STROKE_TAG_END )
dst_tag[0] ^= FT_STROKE_TAG_BEGIN_END;
}
src_point--;
src_tag--;
dst_point++;
dst_tag++;
}
}
left->num_points = left->start;
right->num_points += new_points;
2008-09-16 19:32:02 +02:00
right->movable = FALSE;
left->movable = FALSE;
}
Exit:
return error;
}
2004-12-14 00:16:59 +01:00
/* documentation is in ftstroke.h */
/* there's a lot of magic in this function! */
FT_EXPORT_DEF( FT_Error )
FT_Stroker_EndSubPath( FT_Stroker stroker )
{
2008-09-16 19:32:02 +02:00
FT_Error error = FT_Err_Ok;
if ( stroker->subpath_open )
{
FT_StrokeBorder right = stroker->borders;
[ftstroke] Major revision. The main problems ----------------- o If FT_STROKER_LINEJOIN_BEVEL was specified, unlimited miter joins (not bevel joins) were generated. Indeed, the meanings of `miter' and `bevel' were incorrectly reversed (consistently) in both the code and comments. o The way bevel joins were constructed (whether specified explicitly, or created as a result of exceeding the miter limit) did not match what is required for stroked text in PostScript or PDF. The main fixes -------------- o The behaviour of FT_STROKER_LINEJOIN_BEVEL has been corrected. o A new line join style, FT_STROKER_LINEJOIN_MITER_FIXED, has been introduced to support PostScript and PDF miter joins. o FT_STROKER_LINEJOIN_MITER_VARIABLE has been introduced as an alias for FT_STROKER_LINEJOIN_MITER. Additionally, a variety of stroking errors have been fixed. These would cause various artifacts (including points `at infinity'), especially when stroking poor quality fonts. See http://lists.gnu.org/archive/html/freetype-devel/2011-07/msg00001.html for example documents. The FreeType stroker now produces results very similar to that produced by GhostScript and Distiller for these fonts. Other problems -------------- The following problems have been resolved: o Inside corners could be generated incorrectly. Intersecting the inside corner could cause a missing triangular area and other effects. The intersection point can only be used if the join is between two lines and both lines are long enough. The `optimization' condition in `ft_stroker_inside' has been corrected; this requires the line length to be passed into various functions and stored in `FT_StrokerRec'. o Incorrect cubic curves could be generated. The angle calculations in `FT_Stroker_CubicTo' have been corrected to handle the case of the curve crossing the +/-PI direction. o If the border radius was greater than the radius of curvature of a curve, then the negative sector would end up outside (not inside) the border. This situation is now recognized and the negative sector is circumnavigated in the opposite direction. (If round line joins are being used, this code is disabled because the line join will always cover the negative sector.) o When a curve is split, the arcs may not join smoothly (especially if the curve turns sharply back on itself). Changes in direction between adjacent arcs were not handled. A round corner is now added if the deviation from one arc to the next is greater than a suitable threshold. o The current direction wasn't retained if a the outline contained a zero length lineto or a curve that was determined to be `basically a point'. This could cause a spurious join to be added. o Cubics with close control points could be mishandled. All eight cases are now distinguished correctly. Other improvements ------------------ o Borders for cubic curves could be too `flat'. FT_SMALL_CUBIC_THRESHOLD has been reduced a little to prevent this. o The handling and use of movable points has been simplified a little. o Various values are now computed only if the results are actually needed. o The directions of the outer and inner borders have been swapped, as recommended by Graham Asher. * src/base/ftstroke.c: Revised. * include/freetype/ftstroke.h: Updated.
2011-07-02 12:09:52 +02:00
/* All right, this is an opened path, we need to add a cap between */
/* right & left, add the reverse of left, then add a final cap */
/* between left & right. */
error = ft_stroker_cap( stroker, stroker->angle_in, 0 );
if ( error )
goto Exit;
2008-09-16 19:32:02 +02:00
/* add reversed points from `left' to `right' */
error = ft_stroker_add_reverse_left( stroker, TRUE );
if ( error )
goto Exit;
/* now add the final cap */
stroker->center = stroker->subpath_start;
error = ft_stroker_cap( stroker,
stroker->subpath_angle + FT_ANGLE_PI, 0 );
if ( error )
goto Exit;
/* Now end the right subpath accordingly. The left one is */
/* rewind and doesn't need further processing. */
2008-09-16 19:32:02 +02:00
ft_stroke_border_close( right, FALSE );
}
else
{
FT_Angle turn;
FT_Int inside_side;
[ftstroke] Major revision. The main problems ----------------- o If FT_STROKER_LINEJOIN_BEVEL was specified, unlimited miter joins (not bevel joins) were generated. Indeed, the meanings of `miter' and `bevel' were incorrectly reversed (consistently) in both the code and comments. o The way bevel joins were constructed (whether specified explicitly, or created as a result of exceeding the miter limit) did not match what is required for stroked text in PostScript or PDF. The main fixes -------------- o The behaviour of FT_STROKER_LINEJOIN_BEVEL has been corrected. o A new line join style, FT_STROKER_LINEJOIN_MITER_FIXED, has been introduced to support PostScript and PDF miter joins. o FT_STROKER_LINEJOIN_MITER_VARIABLE has been introduced as an alias for FT_STROKER_LINEJOIN_MITER. Additionally, a variety of stroking errors have been fixed. These would cause various artifacts (including points `at infinity'), especially when stroking poor quality fonts. See http://lists.gnu.org/archive/html/freetype-devel/2011-07/msg00001.html for example documents. The FreeType stroker now produces results very similar to that produced by GhostScript and Distiller for these fonts. Other problems -------------- The following problems have been resolved: o Inside corners could be generated incorrectly. Intersecting the inside corner could cause a missing triangular area and other effects. The intersection point can only be used if the join is between two lines and both lines are long enough. The `optimization' condition in `ft_stroker_inside' has been corrected; this requires the line length to be passed into various functions and stored in `FT_StrokerRec'. o Incorrect cubic curves could be generated. The angle calculations in `FT_Stroker_CubicTo' have been corrected to handle the case of the curve crossing the +/-PI direction. o If the border radius was greater than the radius of curvature of a curve, then the negative sector would end up outside (not inside) the border. This situation is now recognized and the negative sector is circumnavigated in the opposite direction. (If round line joins are being used, this code is disabled because the line join will always cover the negative sector.) o When a curve is split, the arcs may not join smoothly (especially if the curve turns sharply back on itself). Changes in direction between adjacent arcs were not handled. A round corner is now added if the deviation from one arc to the next is greater than a suitable threshold. o The current direction wasn't retained if a the outline contained a zero length lineto or a curve that was determined to be `basically a point'. This could cause a spurious join to be added. o Cubics with close control points could be mishandled. All eight cases are now distinguished correctly. Other improvements ------------------ o Borders for cubic curves could be too `flat'. FT_SMALL_CUBIC_THRESHOLD has been reduced a little to prevent this. o The handling and use of movable points has been simplified a little. o Various values are now computed only if the results are actually needed. o The directions of the outer and inner borders have been swapped, as recommended by Graham Asher. * src/base/ftstroke.c: Revised. * include/freetype/ftstroke.h: Updated.
2011-07-02 12:09:52 +02:00
/* close the path if needed */
if ( stroker->center.x != stroker->subpath_start.x ||
stroker->center.y != stroker->subpath_start.y )
{
[ftstroke] Major revision. The main problems ----------------- o If FT_STROKER_LINEJOIN_BEVEL was specified, unlimited miter joins (not bevel joins) were generated. Indeed, the meanings of `miter' and `bevel' were incorrectly reversed (consistently) in both the code and comments. o The way bevel joins were constructed (whether specified explicitly, or created as a result of exceeding the miter limit) did not match what is required for stroked text in PostScript or PDF. The main fixes -------------- o The behaviour of FT_STROKER_LINEJOIN_BEVEL has been corrected. o A new line join style, FT_STROKER_LINEJOIN_MITER_FIXED, has been introduced to support PostScript and PDF miter joins. o FT_STROKER_LINEJOIN_MITER_VARIABLE has been introduced as an alias for FT_STROKER_LINEJOIN_MITER. Additionally, a variety of stroking errors have been fixed. These would cause various artifacts (including points `at infinity'), especially when stroking poor quality fonts. See http://lists.gnu.org/archive/html/freetype-devel/2011-07/msg00001.html for example documents. The FreeType stroker now produces results very similar to that produced by GhostScript and Distiller for these fonts. Other problems -------------- The following problems have been resolved: o Inside corners could be generated incorrectly. Intersecting the inside corner could cause a missing triangular area and other effects. The intersection point can only be used if the join is between two lines and both lines are long enough. The `optimization' condition in `ft_stroker_inside' has been corrected; this requires the line length to be passed into various functions and stored in `FT_StrokerRec'. o Incorrect cubic curves could be generated. The angle calculations in `FT_Stroker_CubicTo' have been corrected to handle the case of the curve crossing the +/-PI direction. o If the border radius was greater than the radius of curvature of a curve, then the negative sector would end up outside (not inside) the border. This situation is now recognized and the negative sector is circumnavigated in the opposite direction. (If round line joins are being used, this code is disabled because the line join will always cover the negative sector.) o When a curve is split, the arcs may not join smoothly (especially if the curve turns sharply back on itself). Changes in direction between adjacent arcs were not handled. A round corner is now added if the deviation from one arc to the next is greater than a suitable threshold. o The current direction wasn't retained if a the outline contained a zero length lineto or a curve that was determined to be `basically a point'. This could cause a spurious join to be added. o Cubics with close control points could be mishandled. All eight cases are now distinguished correctly. Other improvements ------------------ o Borders for cubic curves could be too `flat'. FT_SMALL_CUBIC_THRESHOLD has been reduced a little to prevent this. o The handling and use of movable points has been simplified a little. o Various values are now computed only if the results are actually needed. o The directions of the outer and inner borders have been swapped, as recommended by Graham Asher. * src/base/ftstroke.c: Revised. * include/freetype/ftstroke.h: Updated.
2011-07-02 12:09:52 +02:00
error = FT_Stroker_LineTo( stroker, &stroker->subpath_start );
if ( error )
goto Exit;
}
/* process the corner */
stroker->angle_out = stroker->subpath_angle;
turn = FT_Angle_Diff( stroker->angle_in,
stroker->angle_out );
/* no specific corner processing is required if the turn is 0 */
if ( turn != 0 )
{
/* when we turn to the right, the inside side is 0 */
inside_side = 0;
/* otherwise, the inside side is 1 */
if ( turn < 0 )
inside_side = 1;
[ftstroke] Major revision. The main problems ----------------- o If FT_STROKER_LINEJOIN_BEVEL was specified, unlimited miter joins (not bevel joins) were generated. Indeed, the meanings of `miter' and `bevel' were incorrectly reversed (consistently) in both the code and comments. o The way bevel joins were constructed (whether specified explicitly, or created as a result of exceeding the miter limit) did not match what is required for stroked text in PostScript or PDF. The main fixes -------------- o The behaviour of FT_STROKER_LINEJOIN_BEVEL has been corrected. o A new line join style, FT_STROKER_LINEJOIN_MITER_FIXED, has been introduced to support PostScript and PDF miter joins. o FT_STROKER_LINEJOIN_MITER_VARIABLE has been introduced as an alias for FT_STROKER_LINEJOIN_MITER. Additionally, a variety of stroking errors have been fixed. These would cause various artifacts (including points `at infinity'), especially when stroking poor quality fonts. See http://lists.gnu.org/archive/html/freetype-devel/2011-07/msg00001.html for example documents. The FreeType stroker now produces results very similar to that produced by GhostScript and Distiller for these fonts. Other problems -------------- The following problems have been resolved: o Inside corners could be generated incorrectly. Intersecting the inside corner could cause a missing triangular area and other effects. The intersection point can only be used if the join is between two lines and both lines are long enough. The `optimization' condition in `ft_stroker_inside' has been corrected; this requires the line length to be passed into various functions and stored in `FT_StrokerRec'. o Incorrect cubic curves could be generated. The angle calculations in `FT_Stroker_CubicTo' have been corrected to handle the case of the curve crossing the +/-PI direction. o If the border radius was greater than the radius of curvature of a curve, then the negative sector would end up outside (not inside) the border. This situation is now recognized and the negative sector is circumnavigated in the opposite direction. (If round line joins are being used, this code is disabled because the line join will always cover the negative sector.) o When a curve is split, the arcs may not join smoothly (especially if the curve turns sharply back on itself). Changes in direction between adjacent arcs were not handled. A round corner is now added if the deviation from one arc to the next is greater than a suitable threshold. o The current direction wasn't retained if a the outline contained a zero length lineto or a curve that was determined to be `basically a point'. This could cause a spurious join to be added. o Cubics with close control points could be mishandled. All eight cases are now distinguished correctly. Other improvements ------------------ o Borders for cubic curves could be too `flat'. FT_SMALL_CUBIC_THRESHOLD has been reduced a little to prevent this. o The handling and use of movable points has been simplified a little. o Various values are now computed only if the results are actually needed. o The directions of the outer and inner borders have been swapped, as recommended by Graham Asher. * src/base/ftstroke.c: Revised. * include/freetype/ftstroke.h: Updated.
2011-07-02 12:09:52 +02:00
error = ft_stroker_inside( stroker,
inside_side,
stroker->subpath_line_length );
if ( error )
goto Exit;
/* process the outside side */
[ftstroke] Major revision. The main problems ----------------- o If FT_STROKER_LINEJOIN_BEVEL was specified, unlimited miter joins (not bevel joins) were generated. Indeed, the meanings of `miter' and `bevel' were incorrectly reversed (consistently) in both the code and comments. o The way bevel joins were constructed (whether specified explicitly, or created as a result of exceeding the miter limit) did not match what is required for stroked text in PostScript or PDF. The main fixes -------------- o The behaviour of FT_STROKER_LINEJOIN_BEVEL has been corrected. o A new line join style, FT_STROKER_LINEJOIN_MITER_FIXED, has been introduced to support PostScript and PDF miter joins. o FT_STROKER_LINEJOIN_MITER_VARIABLE has been introduced as an alias for FT_STROKER_LINEJOIN_MITER. Additionally, a variety of stroking errors have been fixed. These would cause various artifacts (including points `at infinity'), especially when stroking poor quality fonts. See http://lists.gnu.org/archive/html/freetype-devel/2011-07/msg00001.html for example documents. The FreeType stroker now produces results very similar to that produced by GhostScript and Distiller for these fonts. Other problems -------------- The following problems have been resolved: o Inside corners could be generated incorrectly. Intersecting the inside corner could cause a missing triangular area and other effects. The intersection point can only be used if the join is between two lines and both lines are long enough. The `optimization' condition in `ft_stroker_inside' has been corrected; this requires the line length to be passed into various functions and stored in `FT_StrokerRec'. o Incorrect cubic curves could be generated. The angle calculations in `FT_Stroker_CubicTo' have been corrected to handle the case of the curve crossing the +/-PI direction. o If the border radius was greater than the radius of curvature of a curve, then the negative sector would end up outside (not inside) the border. This situation is now recognized and the negative sector is circumnavigated in the opposite direction. (If round line joins are being used, this code is disabled because the line join will always cover the negative sector.) o When a curve is split, the arcs may not join smoothly (especially if the curve turns sharply back on itself). Changes in direction between adjacent arcs were not handled. A round corner is now added if the deviation from one arc to the next is greater than a suitable threshold. o The current direction wasn't retained if a the outline contained a zero length lineto or a curve that was determined to be `basically a point'. This could cause a spurious join to be added. o Cubics with close control points could be mishandled. All eight cases are now distinguished correctly. Other improvements ------------------ o Borders for cubic curves could be too `flat'. FT_SMALL_CUBIC_THRESHOLD has been reduced a little to prevent this. o The handling and use of movable points has been simplified a little. o Various values are now computed only if the results are actually needed. o The directions of the outer and inner borders have been swapped, as recommended by Graham Asher. * src/base/ftstroke.c: Revised. * include/freetype/ftstroke.h: Updated.
2011-07-02 12:09:52 +02:00
error = ft_stroker_outside( stroker,
1 - inside_side,
stroker->subpath_line_length );
if ( error )
goto Exit;
}
/* then end our two subpaths */
[ftstroke] Major revision. The main problems ----------------- o If FT_STROKER_LINEJOIN_BEVEL was specified, unlimited miter joins (not bevel joins) were generated. Indeed, the meanings of `miter' and `bevel' were incorrectly reversed (consistently) in both the code and comments. o The way bevel joins were constructed (whether specified explicitly, or created as a result of exceeding the miter limit) did not match what is required for stroked text in PostScript or PDF. The main fixes -------------- o The behaviour of FT_STROKER_LINEJOIN_BEVEL has been corrected. o A new line join style, FT_STROKER_LINEJOIN_MITER_FIXED, has been introduced to support PostScript and PDF miter joins. o FT_STROKER_LINEJOIN_MITER_VARIABLE has been introduced as an alias for FT_STROKER_LINEJOIN_MITER. Additionally, a variety of stroking errors have been fixed. These would cause various artifacts (including points `at infinity'), especially when stroking poor quality fonts. See http://lists.gnu.org/archive/html/freetype-devel/2011-07/msg00001.html for example documents. The FreeType stroker now produces results very similar to that produced by GhostScript and Distiller for these fonts. Other problems -------------- The following problems have been resolved: o Inside corners could be generated incorrectly. Intersecting the inside corner could cause a missing triangular area and other effects. The intersection point can only be used if the join is between two lines and both lines are long enough. The `optimization' condition in `ft_stroker_inside' has been corrected; this requires the line length to be passed into various functions and stored in `FT_StrokerRec'. o Incorrect cubic curves could be generated. The angle calculations in `FT_Stroker_CubicTo' have been corrected to handle the case of the curve crossing the +/-PI direction. o If the border radius was greater than the radius of curvature of a curve, then the negative sector would end up outside (not inside) the border. This situation is now recognized and the negative sector is circumnavigated in the opposite direction. (If round line joins are being used, this code is disabled because the line join will always cover the negative sector.) o When a curve is split, the arcs may not join smoothly (especially if the curve turns sharply back on itself). Changes in direction between adjacent arcs were not handled. A round corner is now added if the deviation from one arc to the next is greater than a suitable threshold. o The current direction wasn't retained if a the outline contained a zero length lineto or a curve that was determined to be `basically a point'. This could cause a spurious join to be added. o Cubics with close control points could be mishandled. All eight cases are now distinguished correctly. Other improvements ------------------ o Borders for cubic curves could be too `flat'. FT_SMALL_CUBIC_THRESHOLD has been reduced a little to prevent this. o The handling and use of movable points has been simplified a little. o Various values are now computed only if the results are actually needed. o The directions of the outer and inner borders have been swapped, as recommended by Graham Asher. * src/base/ftstroke.c: Revised. * include/freetype/ftstroke.h: Updated.
2011-07-02 12:09:52 +02:00
ft_stroke_border_close( stroker->borders + 0, FALSE );
ft_stroke_border_close( stroker->borders + 1, TRUE );
}
Exit:
return error;
}
2004-12-14 00:16:59 +01:00
/* documentation is in ftstroke.h */
FT_EXPORT_DEF( FT_Error )
FT_Stroker_GetBorderCounts( FT_Stroker stroker,
FT_StrokerBorder border,
FT_UInt *anum_points,
FT_UInt *anum_contours )
{
FT_UInt num_points = 0, num_contours = 0;
FT_Error error;
if ( !stroker || border > 1 )
{
error = FT_THROW( Invalid_Argument );
goto Exit;
}
error = ft_stroke_border_get_counts( stroker->borders + border,
&num_points, &num_contours );
Exit:
if ( anum_points )
*anum_points = num_points;
if ( anum_contours )
*anum_contours = num_contours;
return error;
}
2004-12-14 00:16:59 +01:00
/* documentation is in ftstroke.h */
FT_EXPORT_DEF( FT_Error )
FT_Stroker_GetCounts( FT_Stroker stroker,
FT_UInt *anum_points,
FT_UInt *anum_contours )
{
FT_UInt count1, count2, num_points = 0;
FT_UInt count3, count4, num_contours = 0;
FT_Error error;
error = ft_stroke_border_get_counts( stroker->borders + 0,
&count1, &count2 );
if ( error )
goto Exit;
error = ft_stroke_border_get_counts( stroker->borders + 1,
&count3, &count4 );
if ( error )
goto Exit;
num_points = count1 + count3;
num_contours = count2 + count4;
Exit:
*anum_points = num_points;
*anum_contours = num_contours;
return error;
}
2004-12-14 00:16:59 +01:00
/* documentation is in ftstroke.h */
FT_EXPORT_DEF( void )
FT_Stroker_ExportBorder( FT_Stroker stroker,
FT_StrokerBorder border,
FT_Outline* outline )
{
if ( border == FT_STROKER_BORDER_LEFT ||
border == FT_STROKER_BORDER_RIGHT )
{
FT_StrokeBorder sborder = & stroker->borders[border];
if ( sborder->valid )
ft_stroke_border_export( sborder, outline );
}
}
2004-12-14 00:16:59 +01:00
/* documentation is in ftstroke.h */
FT_EXPORT_DEF( void )
FT_Stroker_Export( FT_Stroker stroker,
FT_Outline* outline )
{
FT_Stroker_ExportBorder( stroker, FT_STROKER_BORDER_LEFT, outline );
FT_Stroker_ExportBorder( stroker, FT_STROKER_BORDER_RIGHT, outline );
}
2004-12-14 00:16:59 +01:00
/* documentation is in ftstroke.h */
/*
* The following is very similar to FT_Outline_Decompose, except
* that we do support opened paths, and do not scale the outline.
*/
FT_EXPORT_DEF( FT_Error )
FT_Stroker_ParseOutline( FT_Stroker stroker,
FT_Outline* outline,
FT_Bool opened )
{
FT_Vector v_last;
FT_Vector v_control;
FT_Vector v_start;
FT_Vector* point;
FT_Vector* limit;
char* tags;
FT_Error error;
[ftstroke] Major revision. The main problems ----------------- o If FT_STROKER_LINEJOIN_BEVEL was specified, unlimited miter joins (not bevel joins) were generated. Indeed, the meanings of `miter' and `bevel' were incorrectly reversed (consistently) in both the code and comments. o The way bevel joins were constructed (whether specified explicitly, or created as a result of exceeding the miter limit) did not match what is required for stroked text in PostScript or PDF. The main fixes -------------- o The behaviour of FT_STROKER_LINEJOIN_BEVEL has been corrected. o A new line join style, FT_STROKER_LINEJOIN_MITER_FIXED, has been introduced to support PostScript and PDF miter joins. o FT_STROKER_LINEJOIN_MITER_VARIABLE has been introduced as an alias for FT_STROKER_LINEJOIN_MITER. Additionally, a variety of stroking errors have been fixed. These would cause various artifacts (including points `at infinity'), especially when stroking poor quality fonts. See http://lists.gnu.org/archive/html/freetype-devel/2011-07/msg00001.html for example documents. The FreeType stroker now produces results very similar to that produced by GhostScript and Distiller for these fonts. Other problems -------------- The following problems have been resolved: o Inside corners could be generated incorrectly. Intersecting the inside corner could cause a missing triangular area and other effects. The intersection point can only be used if the join is between two lines and both lines are long enough. The `optimization' condition in `ft_stroker_inside' has been corrected; this requires the line length to be passed into various functions and stored in `FT_StrokerRec'. o Incorrect cubic curves could be generated. The angle calculations in `FT_Stroker_CubicTo' have been corrected to handle the case of the curve crossing the +/-PI direction. o If the border radius was greater than the radius of curvature of a curve, then the negative sector would end up outside (not inside) the border. This situation is now recognized and the negative sector is circumnavigated in the opposite direction. (If round line joins are being used, this code is disabled because the line join will always cover the negative sector.) o When a curve is split, the arcs may not join smoothly (especially if the curve turns sharply back on itself). Changes in direction between adjacent arcs were not handled. A round corner is now added if the deviation from one arc to the next is greater than a suitable threshold. o The current direction wasn't retained if a the outline contained a zero length lineto or a curve that was determined to be `basically a point'. This could cause a spurious join to be added. o Cubics with close control points could be mishandled. All eight cases are now distinguished correctly. Other improvements ------------------ o Borders for cubic curves could be too `flat'. FT_SMALL_CUBIC_THRESHOLD has been reduced a little to prevent this. o The handling and use of movable points has been simplified a little. o Various values are now computed only if the results are actually needed. o The directions of the outer and inner borders have been swapped, as recommended by Graham Asher. * src/base/ftstroke.c: Revised. * include/freetype/ftstroke.h: Updated.
2011-07-02 12:09:52 +02:00
FT_Int n; /* index of contour in outline */
FT_UInt first; /* index of first point in contour */
FT_Int tag; /* current point's state */
if ( !outline || !stroker )
return FT_THROW( Invalid_Argument );
FT_Stroker_Rewind( stroker );
first = 0;
for ( n = 0; n < outline->n_contours; n++ )
{
FT_UInt last; /* index of last point in contour */
last = outline->contours[n];
limit = outline->points + last;
/* skip empty points; we don't stroke these */
if ( last <= first )
{
first = last + 1;
continue;
}
v_start = outline->points[first];
v_last = outline->points[last];
v_control = v_start;
point = outline->points + first;
2008-09-16 19:32:02 +02:00
tags = outline->tags + first;
tag = FT_CURVE_TAG( tags[0] );
/* A contour cannot start with a cubic control point! */
if ( tag == FT_CURVE_TAG_CUBIC )
goto Invalid_Outline;
/* check first point to determine origin */
if ( tag == FT_CURVE_TAG_CONIC )
{
/* First point is conic control. Yes, this happens. */
if ( FT_CURVE_TAG( outline->tags[last] ) == FT_CURVE_TAG_ON )
{
/* start at last point if it is on the curve */
v_start = v_last;
limit--;
}
else
{
/* if both first and last points are conic, */
/* start at their middle */
v_start.x = ( v_start.x + v_last.x ) / 2;
v_start.y = ( v_start.y + v_last.y ) / 2;
}
point--;
tags--;
}
error = FT_Stroker_BeginSubPath( stroker, &v_start, opened );
if ( error )
goto Exit;
while ( point < limit )
{
point++;
tags++;
tag = FT_CURVE_TAG( tags[0] );
switch ( tag )
{
case FT_CURVE_TAG_ON: /* emit a single line_to */
{
FT_Vector vec;
vec.x = point->x;
vec.y = point->y;
error = FT_Stroker_LineTo( stroker, &vec );
if ( error )
goto Exit;
continue;
}
case FT_CURVE_TAG_CONIC: /* consume conic arcs */
v_control.x = point->x;
v_control.y = point->y;
Do_Conic:
if ( point < limit )
{
FT_Vector vec;
FT_Vector v_middle;
point++;
tags++;
tag = FT_CURVE_TAG( tags[0] );
vec = point[0];
if ( tag == FT_CURVE_TAG_ON )
{
error = FT_Stroker_ConicTo( stroker, &v_control, &vec );
if ( error )
goto Exit;
continue;
}
if ( tag != FT_CURVE_TAG_CONIC )
goto Invalid_Outline;
v_middle.x = ( v_control.x + vec.x ) / 2;
v_middle.y = ( v_control.y + vec.y ) / 2;
error = FT_Stroker_ConicTo( stroker, &v_control, &v_middle );
if ( error )
goto Exit;
v_control = vec;
goto Do_Conic;
}
error = FT_Stroker_ConicTo( stroker, &v_control, &v_start );
goto Close;
default: /* FT_CURVE_TAG_CUBIC */
{
FT_Vector vec1, vec2;
if ( point + 1 > limit ||
FT_CURVE_TAG( tags[1] ) != FT_CURVE_TAG_CUBIC )
goto Invalid_Outline;
point += 2;
tags += 2;
vec1 = point[-2];
vec2 = point[-1];
if ( point <= limit )
{
FT_Vector vec;
vec = point[0];
error = FT_Stroker_CubicTo( stroker, &vec1, &vec2, &vec );
if ( error )
goto Exit;
continue;
}
error = FT_Stroker_CubicTo( stroker, &vec1, &vec2, &v_start );
goto Close;
}
}
}
Close:
if ( error )
goto Exit;
/* don't try to end the path if no segments have been generated */
if ( !stroker->first_point )
{
error = FT_Stroker_EndSubPath( stroker );
if ( error )
goto Exit;
}
first = last + 1;
}
2008-09-16 19:32:02 +02:00
return FT_Err_Ok;
Exit:
return error;
Invalid_Outline:
return FT_THROW( Invalid_Outline );
}
[ftstroke] Major revision. The main problems ----------------- o If FT_STROKER_LINEJOIN_BEVEL was specified, unlimited miter joins (not bevel joins) were generated. Indeed, the meanings of `miter' and `bevel' were incorrectly reversed (consistently) in both the code and comments. o The way bevel joins were constructed (whether specified explicitly, or created as a result of exceeding the miter limit) did not match what is required for stroked text in PostScript or PDF. The main fixes -------------- o The behaviour of FT_STROKER_LINEJOIN_BEVEL has been corrected. o A new line join style, FT_STROKER_LINEJOIN_MITER_FIXED, has been introduced to support PostScript and PDF miter joins. o FT_STROKER_LINEJOIN_MITER_VARIABLE has been introduced as an alias for FT_STROKER_LINEJOIN_MITER. Additionally, a variety of stroking errors have been fixed. These would cause various artifacts (including points `at infinity'), especially when stroking poor quality fonts. See http://lists.gnu.org/archive/html/freetype-devel/2011-07/msg00001.html for example documents. The FreeType stroker now produces results very similar to that produced by GhostScript and Distiller for these fonts. Other problems -------------- The following problems have been resolved: o Inside corners could be generated incorrectly. Intersecting the inside corner could cause a missing triangular area and other effects. The intersection point can only be used if the join is between two lines and both lines are long enough. The `optimization' condition in `ft_stroker_inside' has been corrected; this requires the line length to be passed into various functions and stored in `FT_StrokerRec'. o Incorrect cubic curves could be generated. The angle calculations in `FT_Stroker_CubicTo' have been corrected to handle the case of the curve crossing the +/-PI direction. o If the border radius was greater than the radius of curvature of a curve, then the negative sector would end up outside (not inside) the border. This situation is now recognized and the negative sector is circumnavigated in the opposite direction. (If round line joins are being used, this code is disabled because the line join will always cover the negative sector.) o When a curve is split, the arcs may not join smoothly (especially if the curve turns sharply back on itself). Changes in direction between adjacent arcs were not handled. A round corner is now added if the deviation from one arc to the next is greater than a suitable threshold. o The current direction wasn't retained if a the outline contained a zero length lineto or a curve that was determined to be `basically a point'. This could cause a spurious join to be added. o Cubics with close control points could be mishandled. All eight cases are now distinguished correctly. Other improvements ------------------ o Borders for cubic curves could be too `flat'. FT_SMALL_CUBIC_THRESHOLD has been reduced a little to prevent this. o The handling and use of movable points has been simplified a little. o Various values are now computed only if the results are actually needed. o The directions of the outer and inner borders have been swapped, as recommended by Graham Asher. * src/base/ftstroke.c: Revised. * include/freetype/ftstroke.h: Updated.
2011-07-02 12:09:52 +02:00
/* declare an extern to access `ft_outline_glyph_class' globally */
/* allocated in `ftglyph.c', and use the FT_OUTLINE_GLYPH_CLASS_GET */
/* macro to access it when FT_CONFIG_OPTION_PIC is defined */
Position Independent Code (PIC) support and infrastructure in base. * include/freetype/config/ftoption.h add FT_CONFIG_OPTION_PIC * include/freetype/internal/ftobjs.h Add pic_container member to FT_LibraryRec. Add macros to declare and init instances of FT_CMap_ClassRec. Add macros to init instances of FT_Outline_Funcs and FT_Raster_Funcs. Add macros to declare, allocate and initialize modules (FT_Module_Class). Add macros to declare, allocate and initialize renderers (FT_Renderer_Class). Add macro to init instances of FT_Glyph_Class. Add macros to declare, allocate and initialize drivers (FT_Driver_ClassRec). * include/freetype/internal/ftpic.h new file to declare the FT_PIC_Container struct and the functions to allocate and detroy it. * include/freetype/internal/ftserv.h add macros to allocate and destory arrays of FT_ServiceDescRec. * include/freetype/internal/internal.h define macro to include ftpic.h. New Files: * src/base/ftpic.c implement functions to allocate and destory the global pic_container. * src/base/basepic.h declare struct to hold PIC globals for base and macros to access them. * src/base/basepic.c implement functions to allocate, destroy and initialize PIC globals for base. * src/base/ftinit.c when FT_CONFIG_OPTION_PIC is defined implement functions that allocate and destroy ft_default_modules according to FT_CONFIG_MODULES_H in the pic_container instead of the global scope and use macro from basepic.h to access it. * src/base/ftobjs.c add calls to the functions that allocate and destroy the global pic_container when the library is created and destroyed. * src/base/jamfile add new files to FT2_MULTI build: ftpic.c and basepic.c. * src/base/ftbase.c add new files to build: ftpic.c and basepic.c. * src/base/ftglyph.c when FT_CONFIG_OPTION_PIC is defined ft_bitmap_glyph_class and ft_outline_glyph_class will be allocated in the pic_container instead of the global scope and use macros from basepic.h to access them. * src/base/ftbbox.c allocate bbox_interface stract on the stack instead of the global scope when FT_CONFIG_OPTION_PIC is defined. * src/base/ftstroke.c access ft_outline_glyph_class allocated in ftglyph.c via macros from basepic.h
2009-04-05 16:59:26 +02:00
#ifndef FT_CONFIG_OPTION_PIC
extern const FT_Glyph_Class ft_outline_glyph_class;
Position Independent Code (PIC) support and infrastructure in base. * include/freetype/config/ftoption.h add FT_CONFIG_OPTION_PIC * include/freetype/internal/ftobjs.h Add pic_container member to FT_LibraryRec. Add macros to declare and init instances of FT_CMap_ClassRec. Add macros to init instances of FT_Outline_Funcs and FT_Raster_Funcs. Add macros to declare, allocate and initialize modules (FT_Module_Class). Add macros to declare, allocate and initialize renderers (FT_Renderer_Class). Add macro to init instances of FT_Glyph_Class. Add macros to declare, allocate and initialize drivers (FT_Driver_ClassRec). * include/freetype/internal/ftpic.h new file to declare the FT_PIC_Container struct and the functions to allocate and detroy it. * include/freetype/internal/ftserv.h add macros to allocate and destory arrays of FT_ServiceDescRec. * include/freetype/internal/internal.h define macro to include ftpic.h. New Files: * src/base/ftpic.c implement functions to allocate and destory the global pic_container. * src/base/basepic.h declare struct to hold PIC globals for base and macros to access them. * src/base/basepic.c implement functions to allocate, destroy and initialize PIC globals for base. * src/base/ftinit.c when FT_CONFIG_OPTION_PIC is defined implement functions that allocate and destroy ft_default_modules according to FT_CONFIG_MODULES_H in the pic_container instead of the global scope and use macro from basepic.h to access it. * src/base/ftobjs.c add calls to the functions that allocate and destroy the global pic_container when the library is created and destroyed. * src/base/jamfile add new files to FT2_MULTI build: ftpic.c and basepic.c. * src/base/ftbase.c add new files to build: ftpic.c and basepic.c. * src/base/ftglyph.c when FT_CONFIG_OPTION_PIC is defined ft_bitmap_glyph_class and ft_outline_glyph_class will be allocated in the pic_container instead of the global scope and use macros from basepic.h to access them. * src/base/ftbbox.c allocate bbox_interface stract on the stack instead of the global scope when FT_CONFIG_OPTION_PIC is defined. * src/base/ftstroke.c access ft_outline_glyph_class allocated in ftglyph.c via macros from basepic.h
2009-04-05 16:59:26 +02:00
#endif
#include "basepic.h"
2004-12-14 00:16:59 +01:00
/* documentation is in ftstroke.h */
FT_EXPORT_DEF( FT_Error )
FT_Glyph_Stroke( FT_Glyph *pglyph,
FT_Stroker stroker,
FT_Bool destroy )
{
FT_Error error = FT_ERR( Invalid_Argument );
[ftstroke] Major revision. The main problems ----------------- o If FT_STROKER_LINEJOIN_BEVEL was specified, unlimited miter joins (not bevel joins) were generated. Indeed, the meanings of `miter' and `bevel' were incorrectly reversed (consistently) in both the code and comments. o The way bevel joins were constructed (whether specified explicitly, or created as a result of exceeding the miter limit) did not match what is required for stroked text in PostScript or PDF. The main fixes -------------- o The behaviour of FT_STROKER_LINEJOIN_BEVEL has been corrected. o A new line join style, FT_STROKER_LINEJOIN_MITER_FIXED, has been introduced to support PostScript and PDF miter joins. o FT_STROKER_LINEJOIN_MITER_VARIABLE has been introduced as an alias for FT_STROKER_LINEJOIN_MITER. Additionally, a variety of stroking errors have been fixed. These would cause various artifacts (including points `at infinity'), especially when stroking poor quality fonts. See http://lists.gnu.org/archive/html/freetype-devel/2011-07/msg00001.html for example documents. The FreeType stroker now produces results very similar to that produced by GhostScript and Distiller for these fonts. Other problems -------------- The following problems have been resolved: o Inside corners could be generated incorrectly. Intersecting the inside corner could cause a missing triangular area and other effects. The intersection point can only be used if the join is between two lines and both lines are long enough. The `optimization' condition in `ft_stroker_inside' has been corrected; this requires the line length to be passed into various functions and stored in `FT_StrokerRec'. o Incorrect cubic curves could be generated. The angle calculations in `FT_Stroker_CubicTo' have been corrected to handle the case of the curve crossing the +/-PI direction. o If the border radius was greater than the radius of curvature of a curve, then the negative sector would end up outside (not inside) the border. This situation is now recognized and the negative sector is circumnavigated in the opposite direction. (If round line joins are being used, this code is disabled because the line join will always cover the negative sector.) o When a curve is split, the arcs may not join smoothly (especially if the curve turns sharply back on itself). Changes in direction between adjacent arcs were not handled. A round corner is now added if the deviation from one arc to the next is greater than a suitable threshold. o The current direction wasn't retained if a the outline contained a zero length lineto or a curve that was determined to be `basically a point'. This could cause a spurious join to be added. o Cubics with close control points could be mishandled. All eight cases are now distinguished correctly. Other improvements ------------------ o Borders for cubic curves could be too `flat'. FT_SMALL_CUBIC_THRESHOLD has been reduced a little to prevent this. o The handling and use of movable points has been simplified a little. o Various values are now computed only if the results are actually needed. o The directions of the outer and inner borders have been swapped, as recommended by Graham Asher. * src/base/ftstroke.c: Revised. * include/freetype/ftstroke.h: Updated.
2011-07-02 12:09:52 +02:00
FT_Glyph glyph = NULL;
FT_Library library = stroker->library;
FT_UNUSED( library );
if ( pglyph == NULL )
goto Exit;
glyph = *pglyph;
Position Independent Code (PIC) support and infrastructure in base. * include/freetype/config/ftoption.h add FT_CONFIG_OPTION_PIC * include/freetype/internal/ftobjs.h Add pic_container member to FT_LibraryRec. Add macros to declare and init instances of FT_CMap_ClassRec. Add macros to init instances of FT_Outline_Funcs and FT_Raster_Funcs. Add macros to declare, allocate and initialize modules (FT_Module_Class). Add macros to declare, allocate and initialize renderers (FT_Renderer_Class). Add macro to init instances of FT_Glyph_Class. Add macros to declare, allocate and initialize drivers (FT_Driver_ClassRec). * include/freetype/internal/ftpic.h new file to declare the FT_PIC_Container struct and the functions to allocate and detroy it. * include/freetype/internal/ftserv.h add macros to allocate and destory arrays of FT_ServiceDescRec. * include/freetype/internal/internal.h define macro to include ftpic.h. New Files: * src/base/ftpic.c implement functions to allocate and destory the global pic_container. * src/base/basepic.h declare struct to hold PIC globals for base and macros to access them. * src/base/basepic.c implement functions to allocate, destroy and initialize PIC globals for base. * src/base/ftinit.c when FT_CONFIG_OPTION_PIC is defined implement functions that allocate and destroy ft_default_modules according to FT_CONFIG_MODULES_H in the pic_container instead of the global scope and use macro from basepic.h to access it. * src/base/ftobjs.c add calls to the functions that allocate and destroy the global pic_container when the library is created and destroyed. * src/base/jamfile add new files to FT2_MULTI build: ftpic.c and basepic.c. * src/base/ftbase.c add new files to build: ftpic.c and basepic.c. * src/base/ftglyph.c when FT_CONFIG_OPTION_PIC is defined ft_bitmap_glyph_class and ft_outline_glyph_class will be allocated in the pic_container instead of the global scope and use macros from basepic.h to access them. * src/base/ftbbox.c allocate bbox_interface stract on the stack instead of the global scope when FT_CONFIG_OPTION_PIC is defined. * src/base/ftstroke.c access ft_outline_glyph_class allocated in ftglyph.c via macros from basepic.h
2009-04-05 16:59:26 +02:00
if ( glyph == NULL || glyph->clazz != FT_OUTLINE_GLYPH_CLASS_GET )
goto Exit;
{
FT_Glyph copy;
error = FT_Glyph_Copy( glyph, &copy );
if ( error )
goto Exit;
glyph = copy;
}
{
[ftstroke] Major revision. The main problems ----------------- o If FT_STROKER_LINEJOIN_BEVEL was specified, unlimited miter joins (not bevel joins) were generated. Indeed, the meanings of `miter' and `bevel' were incorrectly reversed (consistently) in both the code and comments. o The way bevel joins were constructed (whether specified explicitly, or created as a result of exceeding the miter limit) did not match what is required for stroked text in PostScript or PDF. The main fixes -------------- o The behaviour of FT_STROKER_LINEJOIN_BEVEL has been corrected. o A new line join style, FT_STROKER_LINEJOIN_MITER_FIXED, has been introduced to support PostScript and PDF miter joins. o FT_STROKER_LINEJOIN_MITER_VARIABLE has been introduced as an alias for FT_STROKER_LINEJOIN_MITER. Additionally, a variety of stroking errors have been fixed. These would cause various artifacts (including points `at infinity'), especially when stroking poor quality fonts. See http://lists.gnu.org/archive/html/freetype-devel/2011-07/msg00001.html for example documents. The FreeType stroker now produces results very similar to that produced by GhostScript and Distiller for these fonts. Other problems -------------- The following problems have been resolved: o Inside corners could be generated incorrectly. Intersecting the inside corner could cause a missing triangular area and other effects. The intersection point can only be used if the join is between two lines and both lines are long enough. The `optimization' condition in `ft_stroker_inside' has been corrected; this requires the line length to be passed into various functions and stored in `FT_StrokerRec'. o Incorrect cubic curves could be generated. The angle calculations in `FT_Stroker_CubicTo' have been corrected to handle the case of the curve crossing the +/-PI direction. o If the border radius was greater than the radius of curvature of a curve, then the negative sector would end up outside (not inside) the border. This situation is now recognized and the negative sector is circumnavigated in the opposite direction. (If round line joins are being used, this code is disabled because the line join will always cover the negative sector.) o When a curve is split, the arcs may not join smoothly (especially if the curve turns sharply back on itself). Changes in direction between adjacent arcs were not handled. A round corner is now added if the deviation from one arc to the next is greater than a suitable threshold. o The current direction wasn't retained if a the outline contained a zero length lineto or a curve that was determined to be `basically a point'. This could cause a spurious join to be added. o Cubics with close control points could be mishandled. All eight cases are now distinguished correctly. Other improvements ------------------ o Borders for cubic curves could be too `flat'. FT_SMALL_CUBIC_THRESHOLD has been reduced a little to prevent this. o The handling and use of movable points has been simplified a little. o Various values are now computed only if the results are actually needed. o The directions of the outer and inner borders have been swapped, as recommended by Graham Asher. * src/base/ftstroke.c: Revised. * include/freetype/ftstroke.h: Updated.
2011-07-02 12:09:52 +02:00
FT_OutlineGlyph oglyph = (FT_OutlineGlyph)glyph;
FT_Outline* outline = &oglyph->outline;
FT_UInt num_points, num_contours;
2008-09-16 19:32:02 +02:00
error = FT_Stroker_ParseOutline( stroker, outline, FALSE );
if ( error )
goto Fail;
(void)FT_Stroker_GetCounts( stroker, &num_points, &num_contours );
FT_Outline_Done( glyph->library, outline );
error = FT_Outline_New( glyph->library,
num_points, num_contours, outline );
if ( error )
goto Fail;
outline->n_points = 0;
outline->n_contours = 0;
FT_Stroker_Export( stroker, outline );
}
if ( destroy )
FT_Done_Glyph( *pglyph );
*pglyph = glyph;
goto Exit;
Fail:
FT_Done_Glyph( glyph );
glyph = NULL;
if ( !destroy )
*pglyph = NULL;
Exit:
return error;
}
2004-12-14 00:16:59 +01:00
/* documentation is in ftstroke.h */
FT_EXPORT_DEF( FT_Error )
FT_Glyph_StrokeBorder( FT_Glyph *pglyph,
FT_Stroker stroker,
FT_Bool inside,
FT_Bool destroy )
{
FT_Error error = FT_ERR( Invalid_Argument );
[ftstroke] Major revision. The main problems ----------------- o If FT_STROKER_LINEJOIN_BEVEL was specified, unlimited miter joins (not bevel joins) were generated. Indeed, the meanings of `miter' and `bevel' were incorrectly reversed (consistently) in both the code and comments. o The way bevel joins were constructed (whether specified explicitly, or created as a result of exceeding the miter limit) did not match what is required for stroked text in PostScript or PDF. The main fixes -------------- o The behaviour of FT_STROKER_LINEJOIN_BEVEL has been corrected. o A new line join style, FT_STROKER_LINEJOIN_MITER_FIXED, has been introduced to support PostScript and PDF miter joins. o FT_STROKER_LINEJOIN_MITER_VARIABLE has been introduced as an alias for FT_STROKER_LINEJOIN_MITER. Additionally, a variety of stroking errors have been fixed. These would cause various artifacts (including points `at infinity'), especially when stroking poor quality fonts. See http://lists.gnu.org/archive/html/freetype-devel/2011-07/msg00001.html for example documents. The FreeType stroker now produces results very similar to that produced by GhostScript and Distiller for these fonts. Other problems -------------- The following problems have been resolved: o Inside corners could be generated incorrectly. Intersecting the inside corner could cause a missing triangular area and other effects. The intersection point can only be used if the join is between two lines and both lines are long enough. The `optimization' condition in `ft_stroker_inside' has been corrected; this requires the line length to be passed into various functions and stored in `FT_StrokerRec'. o Incorrect cubic curves could be generated. The angle calculations in `FT_Stroker_CubicTo' have been corrected to handle the case of the curve crossing the +/-PI direction. o If the border radius was greater than the radius of curvature of a curve, then the negative sector would end up outside (not inside) the border. This situation is now recognized and the negative sector is circumnavigated in the opposite direction. (If round line joins are being used, this code is disabled because the line join will always cover the negative sector.) o When a curve is split, the arcs may not join smoothly (especially if the curve turns sharply back on itself). Changes in direction between adjacent arcs were not handled. A round corner is now added if the deviation from one arc to the next is greater than a suitable threshold. o The current direction wasn't retained if a the outline contained a zero length lineto or a curve that was determined to be `basically a point'. This could cause a spurious join to be added. o Cubics with close control points could be mishandled. All eight cases are now distinguished correctly. Other improvements ------------------ o Borders for cubic curves could be too `flat'. FT_SMALL_CUBIC_THRESHOLD has been reduced a little to prevent this. o The handling and use of movable points has been simplified a little. o Various values are now computed only if the results are actually needed. o The directions of the outer and inner borders have been swapped, as recommended by Graham Asher. * src/base/ftstroke.c: Revised. * include/freetype/ftstroke.h: Updated.
2011-07-02 12:09:52 +02:00
FT_Glyph glyph = NULL;
FT_Library library = stroker->library;
FT_UNUSED( library );
if ( pglyph == NULL )
goto Exit;
glyph = *pglyph;
Position Independent Code (PIC) support and infrastructure in base. * include/freetype/config/ftoption.h add FT_CONFIG_OPTION_PIC * include/freetype/internal/ftobjs.h Add pic_container member to FT_LibraryRec. Add macros to declare and init instances of FT_CMap_ClassRec. Add macros to init instances of FT_Outline_Funcs and FT_Raster_Funcs. Add macros to declare, allocate and initialize modules (FT_Module_Class). Add macros to declare, allocate and initialize renderers (FT_Renderer_Class). Add macro to init instances of FT_Glyph_Class. Add macros to declare, allocate and initialize drivers (FT_Driver_ClassRec). * include/freetype/internal/ftpic.h new file to declare the FT_PIC_Container struct and the functions to allocate and detroy it. * include/freetype/internal/ftserv.h add macros to allocate and destory arrays of FT_ServiceDescRec. * include/freetype/internal/internal.h define macro to include ftpic.h. New Files: * src/base/ftpic.c implement functions to allocate and destory the global pic_container. * src/base/basepic.h declare struct to hold PIC globals for base and macros to access them. * src/base/basepic.c implement functions to allocate, destroy and initialize PIC globals for base. * src/base/ftinit.c when FT_CONFIG_OPTION_PIC is defined implement functions that allocate and destroy ft_default_modules according to FT_CONFIG_MODULES_H in the pic_container instead of the global scope and use macro from basepic.h to access it. * src/base/ftobjs.c add calls to the functions that allocate and destroy the global pic_container when the library is created and destroyed. * src/base/jamfile add new files to FT2_MULTI build: ftpic.c and basepic.c. * src/base/ftbase.c add new files to build: ftpic.c and basepic.c. * src/base/ftglyph.c when FT_CONFIG_OPTION_PIC is defined ft_bitmap_glyph_class and ft_outline_glyph_class will be allocated in the pic_container instead of the global scope and use macros from basepic.h to access them. * src/base/ftbbox.c allocate bbox_interface stract on the stack instead of the global scope when FT_CONFIG_OPTION_PIC is defined. * src/base/ftstroke.c access ft_outline_glyph_class allocated in ftglyph.c via macros from basepic.h
2009-04-05 16:59:26 +02:00
if ( glyph == NULL || glyph->clazz != FT_OUTLINE_GLYPH_CLASS_GET )
goto Exit;
{
FT_Glyph copy;
error = FT_Glyph_Copy( glyph, &copy );
if ( error )
goto Exit;
glyph = copy;
}
{
[ftstroke] Major revision. The main problems ----------------- o If FT_STROKER_LINEJOIN_BEVEL was specified, unlimited miter joins (not bevel joins) were generated. Indeed, the meanings of `miter' and `bevel' were incorrectly reversed (consistently) in both the code and comments. o The way bevel joins were constructed (whether specified explicitly, or created as a result of exceeding the miter limit) did not match what is required for stroked text in PostScript or PDF. The main fixes -------------- o The behaviour of FT_STROKER_LINEJOIN_BEVEL has been corrected. o A new line join style, FT_STROKER_LINEJOIN_MITER_FIXED, has been introduced to support PostScript and PDF miter joins. o FT_STROKER_LINEJOIN_MITER_VARIABLE has been introduced as an alias for FT_STROKER_LINEJOIN_MITER. Additionally, a variety of stroking errors have been fixed. These would cause various artifacts (including points `at infinity'), especially when stroking poor quality fonts. See http://lists.gnu.org/archive/html/freetype-devel/2011-07/msg00001.html for example documents. The FreeType stroker now produces results very similar to that produced by GhostScript and Distiller for these fonts. Other problems -------------- The following problems have been resolved: o Inside corners could be generated incorrectly. Intersecting the inside corner could cause a missing triangular area and other effects. The intersection point can only be used if the join is between two lines and both lines are long enough. The `optimization' condition in `ft_stroker_inside' has been corrected; this requires the line length to be passed into various functions and stored in `FT_StrokerRec'. o Incorrect cubic curves could be generated. The angle calculations in `FT_Stroker_CubicTo' have been corrected to handle the case of the curve crossing the +/-PI direction. o If the border radius was greater than the radius of curvature of a curve, then the negative sector would end up outside (not inside) the border. This situation is now recognized and the negative sector is circumnavigated in the opposite direction. (If round line joins are being used, this code is disabled because the line join will always cover the negative sector.) o When a curve is split, the arcs may not join smoothly (especially if the curve turns sharply back on itself). Changes in direction between adjacent arcs were not handled. A round corner is now added if the deviation from one arc to the next is greater than a suitable threshold. o The current direction wasn't retained if a the outline contained a zero length lineto or a curve that was determined to be `basically a point'. This could cause a spurious join to be added. o Cubics with close control points could be mishandled. All eight cases are now distinguished correctly. Other improvements ------------------ o Borders for cubic curves could be too `flat'. FT_SMALL_CUBIC_THRESHOLD has been reduced a little to prevent this. o The handling and use of movable points has been simplified a little. o Various values are now computed only if the results are actually needed. o The directions of the outer and inner borders have been swapped, as recommended by Graham Asher. * src/base/ftstroke.c: Revised. * include/freetype/ftstroke.h: Updated.
2011-07-02 12:09:52 +02:00
FT_OutlineGlyph oglyph = (FT_OutlineGlyph)glyph;
FT_StrokerBorder border;
FT_Outline* outline = &oglyph->outline;
FT_UInt num_points, num_contours;
border = FT_Outline_GetOutsideBorder( outline );
if ( inside )
{
if ( border == FT_STROKER_BORDER_LEFT )
border = FT_STROKER_BORDER_RIGHT;
else
border = FT_STROKER_BORDER_LEFT;
}
2008-09-16 19:32:02 +02:00
error = FT_Stroker_ParseOutline( stroker, outline, FALSE );
if ( error )
goto Fail;
(void)FT_Stroker_GetBorderCounts( stroker, border,
&num_points, &num_contours );
FT_Outline_Done( glyph->library, outline );
error = FT_Outline_New( glyph->library,
num_points,
num_contours,
outline );
if ( error )
goto Fail;
outline->n_points = 0;
outline->n_contours = 0;
FT_Stroker_ExportBorder( stroker, border, outline );
}
if ( destroy )
FT_Done_Glyph( *pglyph );
*pglyph = glyph;
goto Exit;
Fail:
FT_Done_Glyph( glyph );
glyph = NULL;
if ( !destroy )
*pglyph = NULL;
Exit:
return error;
}
/* END */