updating smooth rasterizer to avoid conflicts later

This commit is contained in:
David Turner 2001-10-18 10:31:05 +00:00
parent 49884d3eeb
commit aef28d5325
2 changed files with 179 additions and 150 deletions

View File

@ -4,7 +4,7 @@
/* */
/* A new `perfect' anti-aliasing renderer (body). */
/* */
/* Copyright 2000 by */
/* Copyright 2000-2001 by */
/* David Turner, Robert Wilhelm, and Werner Lemberg. */
/* */
/* This file is part of the FreeType project, and may only be used, */
@ -32,8 +32,8 @@
/* cc -c -D_STANDALONE_ ftgrays.c */
/* */
/* The renderer can be initialized with a call to */
/* `ft_grays_raster.grays_raster_new'; an anti-aliased bitmap can be */
/* generated with a call to `ft_grays_raster.grays_raster_render'. */
/* `ft_gray_raster.gray_raster_new'; an anti-aliased bitmap can be */
/* generated with a call to `ft_gray_raster.gray_raster_render'. */
/* */
/* See the comments and documentation in the file `ftimage.h' for */
/* more details on how the raster works. */
@ -201,9 +201,36 @@
/* */
/* TYPE DEFINITIONS */
/* */
/* don't change the following types to FT_Int or FT_Pos, since we might */
/* need to define them to "float" or "double" when experimenting with */
/* new algorithms */
typedef int TScan; /* integer scanline/pixel coordinate */
typedef long TPos; /* sub-pixel coordinate */
/* determine the type used to store cell areas. This normally takes at */
/* least PIXEL_BYTES*2 + 1. On 16-bit systems, we need to use `long' */
/* instead of `int', otherwise bad things happen */
#if PIXEL_BITS <= 7
typedef int TArea;
#else /* PIXEL_BITS >= 8 */
/* approximately determine the size of integers using an ANSI-C header */
#include <limits.h>
#if UINT_MAX == 0xFFFFU
typedef long TArea;
#else
typedef int TArea;
#endif
#endif /* PIXEL_BITS >= 8 */
/* maximal number of gray spans in a call to the span callback */
#define FT_MAX_GRAY_SPANS 32
@ -226,7 +253,7 @@
TScan x;
TScan y;
int cover;
int area;
TArea area;
} TCell, *PCell;
@ -242,7 +269,7 @@
TScan min_ex, max_ex;
TScan min_ey, max_ey;
int area;
TArea area;
int cover;
int invalid;
@ -266,12 +293,12 @@
void* render_span_data;
int span_y;
int band_size;
int band_shoot;
int conic_level;
int cubic_level;
int band_size;
int band_shoot;
int conic_level;
int cubic_level;
void* memory;
void* memory;
jmp_buf jump_buffer;
} TRaster, *PRaster;
@ -281,9 +308,9 @@
/* */
/* Initialize the cells table. */
/* */
static
void init_cells( RAS_ARG_ void* buffer,
long byte_size )
static void
gray_init_cells( RAS_ARG_ void* buffer,
long byte_size )
{
ras.cells = (PCell)buffer;
ras.max_cells = byte_size / sizeof ( TCell );
@ -298,8 +325,8 @@
/* */
/* Compute the outline bounding box. */
/* */
static
void compute_cbox( RAS_ARG )
static void
gray_compute_cbox( RAS_ARG )
{
FT_Outline* outline = &ras.outline;
FT_Vector* vec = outline->points;
@ -342,8 +369,8 @@
/* */
/* Record the current cell in the table. */
/* */
static
void record_cell( RAS_ARG )
static void
gray_record_cell( RAS_ARG )
{
PCell cell;
@ -366,9 +393,9 @@
/* */
/* Set the current cell to a new position. */
/* */
static
void set_cell( RAS_ARG_ TScan ex,
TScan ey )
static void
gray_set_cell( RAS_ARG_ TScan ex,
TScan ey )
{
int invalid, record, clean;
@ -405,7 +432,7 @@
/* record the previous cell if needed (i.e., if we changed the cell */
/* position, of changed the `invalid' flag) */
if ( ras.invalid != invalid || record )
record_cell( RAS_VAR );
gray_record_cell( RAS_VAR );
if ( clean )
{
@ -423,9 +450,9 @@
/* */
/* Start a new contour at a given cell. */
/* */
static
void start_cell( RAS_ARG_ TScan ex,
TScan ey )
static void
gray_start_cell( RAS_ARG_ TScan ex,
TScan ey )
{
if ( ex < ras.min_ex )
ex = ras.min_ex - 1;
@ -437,7 +464,7 @@
ras.last_ey = SUBPIXELS( ey );
ras.invalid = 0;
set_cell( RAS_VAR_ ex, ey );
gray_set_cell( RAS_VAR_ ex, ey );
}
@ -445,12 +472,12 @@
/* */
/* Render a scanline as one or more cells. */
/* */
static
void render_scanline( RAS_ARG_ TScan ey,
TPos x1,
TScan y1,
TPos x2,
TScan y2 )
static void
gray_render_scanline( RAS_ARG_ TScan ey,
TPos x1,
TScan y1,
TPos x2,
TScan y2 )
{
TScan ex1, ex2, fx1, fx2, delta;
long p, first, dx;
@ -467,7 +494,7 @@
/* trivial case. Happens often */
if ( y1 == y2 )
{
set_cell( RAS_VAR_ ex2, ey );
gray_set_cell( RAS_VAR_ ex2, ey );
return;
}
@ -476,7 +503,7 @@
if ( ex1 == ex2 )
{
delta = y2 - y1;
ras.area += ( fx1 + fx2 ) * delta;
ras.area += (TArea)( fx1 + fx2 ) * delta;
ras.cover += delta;
return;
}
@ -504,11 +531,11 @@
mod += dx;
}
ras.area += ( fx1 + first ) * delta;
ras.area += (TArea)( fx1 + first ) * delta;
ras.cover += delta;
ex1 += incr;
set_cell( RAS_VAR_ ex1, ey );
gray_set_cell( RAS_VAR_ ex1, ey );
y1 += delta;
if ( ex1 != ex2 )
@ -534,16 +561,16 @@
delta++;
}
ras.area += ONE_PIXEL * delta;
ras.area += (TArea)ONE_PIXEL * delta;
ras.cover += delta;
y1 += delta;
ex1 += incr;
set_cell( RAS_VAR_ ex1, ey );
gray_set_cell( RAS_VAR_ ex1, ey );
}
}
delta = y2 - y1;
ras.area += ( fx2 + ONE_PIXEL - first ) * delta;
ras.area += (TArea)( fx2 + ONE_PIXEL - first ) * delta;
ras.cover += delta;
}
@ -552,8 +579,8 @@
/* */
/* Render a given line as a series of scanlines. */
/* */
static
void render_line( RAS_ARG_ TPos to_x,
static void
gray_render_line( RAS_ARG_ TPos to_x,
TPos to_y )
{
TScan ey1, ey2, fy1, fy2;
@ -591,7 +618,7 @@
/* everything is on a single scanline */
if ( ey1 == ey2 )
{
render_scanline( RAS_VAR_ ey1, ras.x, fy1, to_x, fy2 );
gray_render_scanline( RAS_VAR_ ey1, ras.x, fy1, to_x, fy2 );
goto End;
}
@ -617,10 +644,10 @@
}
x = ras.x + delta;
render_scanline( RAS_VAR_ ey1, ras.x, fy1, x, first );
gray_render_scanline( RAS_VAR_ ey1, ras.x, fy1, x, first );
ey1 += incr;
set_cell( RAS_VAR_ TRUNC( x ), ey1 );
gray_set_cell( RAS_VAR_ TRUNC( x ), ey1 );
if ( ey1 != ey2 )
{
@ -645,15 +672,15 @@
}
x2 = x + delta;
render_scanline( RAS_VAR_ ey1, x, ONE_PIXEL - first, x2, first );
gray_render_scanline( RAS_VAR_ ey1, x, ONE_PIXEL - first, x2, first );
x = x2;
ey1 += incr;
set_cell( RAS_VAR_ TRUNC( x ), ey1 );
gray_set_cell( RAS_VAR_ TRUNC( x ), ey1 );
}
}
render_scanline( RAS_VAR_ ey1, x, ONE_PIXEL - first, to_x, fy2 );
gray_render_scanline( RAS_VAR_ ey1, x, ONE_PIXEL - first, to_x, fy2 );
End:
ras.x = to_x;
@ -662,8 +689,8 @@
}
static
void split_conic( FT_Vector* base )
static void
gray_split_conic( FT_Vector* base )
{
TPos a, b;
@ -682,8 +709,8 @@
}
static
void render_conic( RAS_ARG_ FT_Vector* control,
static void
gray_render_conic( RAS_ARG_ FT_Vector* control,
FT_Vector* to )
{
TPos dx, dy;
@ -713,7 +740,7 @@
if ( level <= 1 )
{
/* we compute the mid-point directly in order to avoid */
/* calling split_conic() */
/* calling gray_split_conic() */
TPos to_x, to_y, mid_x, mid_y;
@ -722,8 +749,8 @@
mid_x = ( ras.x + to_x + 2 * UPSCALE( control->x ) ) / 4;
mid_y = ( ras.y + to_y + 2 * UPSCALE( control->y ) ) / 4;
render_line( RAS_VAR_ mid_x, mid_y );
render_line( RAS_VAR_ to_x, to_y );
gray_render_line( RAS_VAR_ mid_x, mid_y );
gray_render_line( RAS_VAR_ to_x, to_y );
return;
}
@ -761,7 +788,7 @@
if ( TRUNC( min ) >= ras.max_ey || TRUNC( max ) < 0 )
goto Draw;
split_conic( arc );
gray_split_conic( arc );
arc += 2;
top++;
levels[top] = levels[top - 1] = level - 1;
@ -778,8 +805,8 @@
mid_x = ( ras.x + to_x + 2 * arc[1].x ) / 4;
mid_y = ( ras.y + to_y + 2 * arc[1].y ) / 4;
render_line( RAS_VAR_ mid_x, mid_y );
render_line( RAS_VAR_ to_x, to_y );
gray_render_line( RAS_VAR_ mid_x, mid_y );
gray_render_line( RAS_VAR_ to_x, to_y );
top--;
arc -= 2;
@ -789,8 +816,8 @@
}
static
void split_cubic( FT_Vector* base )
static void
gray_split_cubic( FT_Vector* base )
{
TPos a, b, c, d;
@ -817,8 +844,8 @@
}
static
void render_cubic( RAS_ARG_ FT_Vector* control1,
static void
gray_render_cubic( RAS_ARG_ FT_Vector* control1,
FT_Vector* control2,
FT_Vector* to )
{
@ -870,8 +897,8 @@
mid_y = ( ras.y + to_y +
3 * UPSCALE( control1->y + control2->y ) ) / 8;
render_line( RAS_VAR_ mid_x, mid_y );
render_line( RAS_VAR_ to_x, to_y );
gray_render_line( RAS_VAR_ mid_x, mid_y );
gray_render_line( RAS_VAR_ to_x, to_y );
return;
}
@ -910,7 +937,7 @@
if ( y > max ) max = y;
if ( TRUNC( min ) >= ras.max_ey || TRUNC( max ) < 0 )
goto Draw;
split_cubic( arc );
gray_split_cubic( arc );
arc += 3;
top ++;
levels[top] = levels[top - 1] = level - 1;
@ -927,8 +954,8 @@
mid_x = ( ras.x + to_x + 3 * ( arc[1].x + arc[2].x ) ) / 8;
mid_y = ( ras.y + to_y + 3 * ( arc[1].y + arc[2].y ) ) / 8;
render_line( RAS_VAR_ mid_x, mid_y );
render_line( RAS_VAR_ to_x, to_y );
gray_render_line( RAS_VAR_ mid_x, mid_y );
gray_render_line( RAS_VAR_ to_x, to_y );
top --;
arc -= 3;
}
@ -963,9 +990,9 @@
/* a simple shell sort algorithm that works directly on our */
/* cells table */
static
void shell_sort ( PCell cells,
int count )
static void
gray_shell_sort ( PCell cells,
int count )
{
PCell i, j, limit = cells + count;
TCell temp;
@ -1009,9 +1036,9 @@
#define QSORT_THRESHOLD 9 /* below this size, a sub-array will be sorted */
/* through a normal insertion sort */
static
void quick_sort( PCell cells,
int count )
static void
gray_quick_sort( PCell cells,
int count )
{
PCell stack[40]; /* should be enough ;-) */
PCell* top; /* top of stack */
@ -1109,8 +1136,8 @@
#ifdef DEBUG_GRAYS
#ifdef DEBUG_SORT
static
int check_sort( PCell cells,
static int
gray_check_sort( PCell cells,
int count )
{
PCell p, q;
@ -1129,21 +1156,21 @@
#endif /* DEBUG_GRAYS */
static
int Move_To( FT_Vector* to,
static int
gray_move_to( FT_Vector* to,
FT_Raster raster )
{
TPos x, y;
/* record current cell, if any */
record_cell( (PRaster)raster );
gray_record_cell( (PRaster)raster );
/* start to a new position */
x = UPSCALE( to->x );
y = UPSCALE( to->y );
start_cell( (PRaster)raster, TRUNC( x ), TRUNC( y ) );
gray_start_cell( (PRaster)raster, TRUNC( x ), TRUNC( y ) );
((PRaster)raster)->x = x;
((PRaster)raster)->y = y;
@ -1151,42 +1178,42 @@
}
static
int Line_To( FT_Vector* to,
static int
gray_line_to( FT_Vector* to,
FT_Raster raster )
{
render_line( (PRaster)raster,
UPSCALE( to->x ), UPSCALE( to->y ) );
gray_render_line( (PRaster)raster,
UPSCALE( to->x ), UPSCALE( to->y ) );
return 0;
}
static
int Conic_To( FT_Vector* control,
static int
gray_conic_to( FT_Vector* control,
FT_Vector* to,
FT_Raster raster )
{
render_conic( (PRaster)raster, control, to );
gray_render_conic( (PRaster)raster, control, to );
return 0;
}
static
int Cubic_To( FT_Vector* control1,
static int
gray_cubic_to( FT_Vector* control1,
FT_Vector* control2,
FT_Vector* to,
FT_Raster raster )
{
render_cubic( (PRaster)raster, control1, control2, to );
gray_render_cubic( (PRaster)raster, control1, control2, to );
return 0;
}
static
void grays_render_span( int y,
int count,
FT_Span* spans,
PRaster raster )
static void
gray_render_span( int y,
int count,
FT_Span* spans,
PRaster raster )
{
unsigned char* p;
FT_Bitmap* map = &raster->target;
@ -1218,8 +1245,8 @@
#include <stdio.h>
static
void dump_cells( RAS_ARG )
static void
gray_dump_cells( RAS_ARG )
{
PCell cell, limit;
int y = -1;
@ -1244,11 +1271,11 @@
#endif /* DEBUG_GRAYS */
static
void grays_hline( RAS_ARG_ TScan x,
TScan y,
TPos area,
int acount )
static void
gray_hline( RAS_ARG_ TScan x,
TScan y,
TPos area,
int acount )
{
FT_Span* span;
int count;
@ -1344,10 +1371,11 @@
}
static
void grays_sweep( RAS_ARG_ FT_Bitmap* target )
static void
gray_sweep( RAS_ARG_ FT_Bitmap* target )
{
TScan x, y, cover, area;
TScan x, y, cover;
TArea area;
PCell start, cur, limit;
FT_UNUSED( target );
@ -1386,7 +1414,7 @@
/* individual gray pixel there */
if ( area && x >= 0 )
{
grays_hline( RAS_VAR_ x, y, cover * ( ONE_PIXEL * 2 ) - area, 1 );
gray_hline( RAS_VAR_ x, y, cover * ( ONE_PIXEL * 2 ) - area, 1 );
x++;
}
@ -1397,14 +1425,14 @@
{
/* draw a gray span between the start cell and the current one */
if ( cur->x > x )
grays_hline( RAS_VAR_ x, y,
gray_hline( RAS_VAR_ x, y,
cover * ( ONE_PIXEL * 2 ), cur->x - x );
}
else
{
/* draw a gray span until the end of the clipping region */
if ( cover && x < ras.max_ex - ras.min_ex )
grays_hline( RAS_VAR_ x, y,
gray_hline( RAS_VAR_ x, y,
cover * ( ONE_PIXEL * 2 ),
ras.max_ex - x - ras.min_ex );
cover = 0;
@ -1478,9 +1506,9 @@
{
#undef SCALED
#if 0
# define SCALED( x ) ( ( (x) << shift ) - delta )
#define SCALED( x ) ( ( (x) << shift ) - delta )
#else
# define SCALED( x) (x)
#define SCALED( x ) (x)
#endif
FT_Vector v_last;
@ -1688,15 +1716,15 @@
static int
grays_convert_glyph_inner( RAS_ARG )
gray_convert_glyph_inner( RAS_ARG )
{
static
const FT_Outline_Funcs interface =
{
(FT_Outline_MoveTo_Func) Move_To,
(FT_Outline_LineTo_Func) Line_To,
(FT_Outline_ConicTo_Func)Conic_To,
(FT_Outline_CubicTo_Func)Cubic_To,
(FT_Outline_MoveTo_Func) gray_move_to,
(FT_Outline_LineTo_Func) gray_line_to,
(FT_Outline_ConicTo_Func)gray_conic_to,
(FT_Outline_CubicTo_Func)gray_cubic_to,
0,
0
};
@ -1706,7 +1734,7 @@
if ( setjmp( ras.jump_buffer ) == 0 )
{
error = FT_Outline_Decompose( &ras.outline, &interface, &ras );
record_cell( RAS_VAR );
gray_record_cell( RAS_VAR );
}
else
{
@ -1717,8 +1745,8 @@
}
static
int grays_convert_glyph( RAS_ARG_ FT_Outline* outline )
static int
gray_convert_glyph( RAS_ARG )
{
TBand bands[40], *band;
int n, num_bands;
@ -1727,7 +1755,7 @@
/* Set up state in the raster object */
compute_cbox( RAS_VAR );
gray_compute_cbox( RAS_VAR );
/* clip to target bitmap, exit if nothing to do */
clip = &ras.clip_box;
@ -1743,7 +1771,8 @@
if ( ras.max_ey > clip->yMax ) ras.max_ey = clip->yMax;
/* simple heuristic used to speed-up the bezier decomposition -- see */
/* the code in render_conic() and render_cubic() for more details */
/* the code in gray_render_conic() and gray_render_cubic() for more */
/* details */
ras.conic_level = 32;
ras.cubic_level = 16;
@ -1792,26 +1821,26 @@
ras.max_ey = band->max;
#if 1
error = grays_convert_glyph_inner( RAS_VAR );
error = gray_convert_glyph_inner( RAS_VAR );
#else
error = FT_Outline_Decompose( outline, &interface, &ras ) ||
record_cell( RAS_VAR );
gray_record_cell( RAS_VAR );
#endif
if ( !error )
{
#ifdef SHELL_SORT
shell_sort( ras.cells, ras.num_cells );
gray_shell_sort( ras.cells, ras.num_cells );
#else
quick_sort( ras.cells, ras.num_cells );
gray_quick_sort( ras.cells, ras.num_cells );
#endif
#ifdef DEBUG_GRAYS
check_sort( ras.cells, ras.num_cells );
dump_cells( RAS_VAR );
gray_check_sort( ras.cells, ras.num_cells );
gray_dump_cells( RAS_VAR );
#endif
grays_sweep( RAS_VAR_ &ras.target );
gray_sweep( RAS_VAR_ &ras.target );
band--;
continue;
}
@ -1851,9 +1880,9 @@
}
extern
int grays_raster_render( PRaster raster,
FT_Raster_Params* params )
extern int
gray_raster_render( PRaster raster,
FT_Raster_Params* params )
{
FT_Outline* outline = (FT_Outline*)params->source;
FT_Bitmap* target_map = params->target;
@ -1910,7 +1939,7 @@
if ( target_map )
ras.target = *target_map;
ras.render_span = (FT_Raster_Span_Func)grays_render_span;
ras.render_span = (FT_Raster_Span_Func)gray_render_span;
ras.render_span_data = &ras;
if ( params->flags & ft_raster_flag_direct )
@ -1919,7 +1948,7 @@
ras.render_span_data = params->user;
}
return grays_convert_glyph( (PRaster)raster, outline );
return gray_convert_glyph( (PRaster)raster );
}
@ -1928,9 +1957,9 @@
#ifdef _STANDALONE_
static
int grays_raster_new( void* memory,
FT_Raster* araster )
static int
gray_raster_new( void* memory,
FT_Raster* araster )
{
static TRaster the_raster;
@ -1944,8 +1973,8 @@
}
static
void grays_raster_done( FT_Raster raster )
static void
gray_raster_done( FT_Raster raster )
{
/* nothing */
FT_UNUSED( raster );
@ -1953,9 +1982,9 @@
#else /* _STANDALONE_ */
static
int grays_raster_new( FT_Memory memory,
FT_Raster* araster )
static int
gray_raster_new( FT_Memory memory,
FT_Raster* araster )
{
FT_Error error;
PRaster raster;
@ -1972,8 +2001,8 @@
}
static
void grays_raster_done( FT_Raster raster )
static void
gray_raster_done( FT_Raster raster )
{
FT_Memory memory = (FT_Memory)((PRaster)raster)->memory;
@ -1984,16 +2013,16 @@
#endif /* _STANDALONE_ */
static
void grays_raster_reset( FT_Raster raster,
const char* pool_base,
long pool_size )
static void
gray_raster_reset( FT_Raster raster,
const char* pool_base,
long pool_size )
{
PRaster rast = (PRaster)raster;
if ( raster && pool_base && pool_size >= 4096 )
init_cells( rast, (char*)pool_base, pool_size );
gray_init_cells( rast, (char*)pool_base, pool_size );
rast->band_size = ( pool_size / sizeof ( TCell ) ) / 8;
}
@ -2003,11 +2032,11 @@
{
ft_glyph_format_outline,
(FT_Raster_New_Func) grays_raster_new,
(FT_Raster_Reset_Func) grays_raster_reset,
(FT_Raster_Set_Mode_Func)0,
(FT_Raster_Render_Func) grays_raster_render,
(FT_Raster_Done_Func) grays_raster_done
(FT_Raster_New_Func) gray_raster_new,
(FT_Raster_Reset_Func) gray_raster_reset,
(FT_Raster_Set_Mode_Func) 0,
(FT_Raster_Render_Func) gray_raster_render,
(FT_Raster_Done_Func) gray_raster_done
};

View File

@ -4,7 +4,7 @@
/* */
/* FreeType smooth renderer declaration */
/* */
/* Copyright 1996-2000 by */
/* Copyright 1996-2001 by */
/* David Turner, Robert Wilhelm, and Werner Lemberg. */
/* */
/* This file is part of the FreeType project, and may only be used, */