freetype2/src/type1/t1gload.c

317 lines
12 KiB
C

/***************************************************************************/
/* */
/* t1gload.c */
/* */
/* Type 1 Glyph Loader (body). */
/* */
/* Copyright 1996-2000 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. */
/* */
/***************************************************************************/
#ifdef FT_FLAT_COMPILE
#include "t1gload.h"
#else
#include <type1/t1gload.h>
#endif
#include <freetype/internal/ftdebug.h>
#include <freetype/internal/ftstream.h>
#include <freetype/ftoutln.h>
#include <freetype/internal/psaux.h>
#include <string.h> /* for strcmp() */
/*************************************************************************/
/* */
/* The macro FT_COMPONENT is used in trace mode. It is an implicit */
/* parameter of the FT_TRACE() and FT_ERROR() macros, used to print/log */
/* messages during execution. */
/* */
#undef FT_COMPONENT
#define FT_COMPONENT trace_t1gload
/*************************************************************************/
/*************************************************************************/
/*************************************************************************/
/********** *********/
/********** COMPUTE THE MAXIMUM ADVANCE WIDTH *********/
/********** *********/
/********** The following code is in charge of computing *********/
/********** the maximum advance width of the font. It *********/
/********** quickly processes each glyph charstring to *********/
/********** extract the value from either a `sbw' or `seac' *********/
/********** operator. *********/
/********** *********/
/*************************************************************************/
/*************************************************************************/
/*************************************************************************/
FT_CALLBACK_DEF
FT_Error T1_Parse_Glyph( T1_Decoder* decoder,
FT_UInt glyph_index )
{
T1_Face face = (T1_Face)decoder->builder.face;
T1_Font* type1 = &face->type1;
decoder->font_matrix = type1->font_matrix;
decoder->font_offset = type1->font_offset;
return decoder->funcs.parse_charstrings(
decoder,
type1->charstrings [glyph_index],
type1->charstrings_len[glyph_index] );
}
FT_LOCAL_DEF
FT_Error T1_Compute_Max_Advance( T1_Face face,
FT_Int* max_advance )
{
FT_Error error;
T1_Decoder decoder;
FT_Int glyph_index;
T1_Font* type1 = &face->type1;
PSAux_Interface* psaux = (PSAux_Interface*)face->psaux;
*max_advance = 0;
/* initialize load decoder */
error = psaux->t1_decoder_funcs->init( &decoder,
(FT_Face)face,
0, /* size */
0, /* glyph slot */
(FT_Byte**)type1->glyph_names,
face->blend,
T1_Parse_Glyph );
if ( error )
return error;
decoder.builder.metrics_only = 1;
decoder.builder.load_points = 0;
decoder.num_subrs = type1->num_subrs;
decoder.subrs = type1->subrs;
decoder.subrs_len = type1->subrs_len;
/* for each glyph, parse the glyph charstring and extract */
/* the advance width */
for ( glyph_index = 0; glyph_index < type1->num_glyphs; glyph_index++ )
{
/* now get load the unscaled outline */
error = T1_Parse_Glyph( &decoder, glyph_index );
/* ignore the error if one occured - skip to next glyph */
}
*max_advance = decoder.builder.advance.x;
return FT_Err_Ok;
}
/*************************************************************************/
/*************************************************************************/
/*************************************************************************/
/********** *********/
/********** UNHINTED GLYPH LOADER *********/
/********** *********/
/********** The following code is in charge of loading a *********/
/********** single outline. It completely ignores hinting *********/
/********** and is used when FT_LOAD_NO_HINTING is set. *********/
/********** *********/
/********** The Type 1 hinter is located in `t1hint.c' *********/
/********** *********/
/*************************************************************************/
/*************************************************************************/
/*************************************************************************/
FT_LOCAL_DEF
FT_Error T1_Load_Glyph( T1_GlyphSlot glyph,
T1_Size size,
FT_Int glyph_index,
FT_Int load_flags )
{
FT_Error error;
T1_Decoder decoder;
T1_Face face = (T1_Face)glyph->root.face;
FT_Bool hinting;
T1_Font* type1 = &face->type1;
PSAux_Interface* psaux = (PSAux_Interface*)face->psaux;
const T1_Decoder_Funcs* decoder_funcs = psaux->t1_decoder_funcs;
FT_Matrix font_matrix;
FT_Vector font_offset;
if ( load_flags & FT_LOAD_NO_RECURSE )
load_flags |= FT_LOAD_NO_SCALE | FT_LOAD_NO_HINTING;
glyph->x_scale = size->root.metrics.x_scale;
glyph->y_scale = size->root.metrics.y_scale;
glyph->root.outline.n_points = 0;
glyph->root.outline.n_contours = 0;
hinting = ( load_flags & FT_LOAD_NO_SCALE ) == 0 &&
( load_flags & FT_LOAD_NO_HINTING ) == 0;
glyph->root.format = ft_glyph_format_outline;
error = decoder_funcs->init( &decoder,
(FT_Face)face,
(FT_Size)size,
(FT_GlyphSlot)glyph,
(FT_Byte**)type1->glyph_names,
face->blend,
T1_Parse_Glyph );
if ( error )
goto Exit;
decoder.builder.no_recurse = ( ( load_flags & FT_LOAD_NO_RECURSE ) != 0 );
decoder.num_subrs = type1->num_subrs;
decoder.subrs = type1->subrs;
decoder.subrs_len = type1->subrs_len;
/* now load the unscaled outline */
error = T1_Parse_Glyph( &decoder, glyph_index );
if ( error )
goto Exit;
font_matrix = decoder.font_matrix;
font_offset = decoder.font_offset;
/* save new glyph tables */
decoder_funcs->done( &decoder );
/* now, set the metrics -- this is rather simple, as */
/* the left side bearing is the xMin, and the top side */
/* bearing the yMax */
if ( !error )
{
glyph->root.outline.flags &= ft_outline_owner;
glyph->root.outline.flags |= ft_outline_reverse_fill;
/* for composite glyphs, return only left side bearing and */
/* advance width */
if ( load_flags & FT_LOAD_NO_RECURSE )
{
FT_Slot_Internal internal = glyph->root.internal;
glyph->root.metrics.horiBearingX = decoder.builder.left_bearing.x;
glyph->root.metrics.horiAdvance = decoder.builder.advance.x;
internal->glyph_matrix = font_matrix;
internal->glyph_delta = font_offset;
internal->glyph_transformed = 1;
}
else
{
FT_BBox cbox;
FT_Glyph_Metrics* metrics = &glyph->root.metrics;
/* copy the _unscaled_ advance width */
metrics->horiAdvance = decoder.builder.advance.x;
glyph->root.linearHoriAdvance = decoder.builder.advance.x;
glyph->root.internal->glyph_transformed = 0;
/* make up vertical metrics */
metrics->vertBearingX = 0;
metrics->vertBearingY = 0;
metrics->vertAdvance = 0;
glyph->root.linearVertAdvance = 0;
glyph->root.format = ft_glyph_format_outline;
if ( size && size->root.metrics.y_ppem < 24 )
glyph->root.outline.flags |= ft_outline_high_precision;
/* apply the font matrix */
FT_Outline_Transform( &glyph->root.outline, &font_matrix );
FT_Outline_Translate( &glyph->root.outline,
font_offset.x,
font_offset.y );
#if 0
glyph->root.outline.second_pass = TRUE;
glyph->root.outline.high_precision = size->root.metrics.y_ppem < 24;
glyph->root.outline.dropout_mode = 2;
#endif /* 0 */
if ( ( load_flags & FT_LOAD_NO_SCALE ) == 0 )
{
/* scale the outline and the metrics */
FT_Int n;
FT_Outline* cur = decoder.builder.base;
FT_Vector* vec = cur->points;
FT_Fixed x_scale = glyph->x_scale;
FT_Fixed y_scale = glyph->y_scale;
/* First of all, scale the points */
for ( n = cur->n_points; n > 0; n--, vec++ )
{
vec->x = FT_MulFix( vec->x, x_scale );
vec->y = FT_MulFix( vec->y, y_scale );
}
FT_Outline_Get_CBox( &glyph->root.outline, &cbox );
/* Then scale the metrics */
metrics->horiAdvance = FT_MulFix( metrics->horiAdvance, x_scale );
metrics->vertAdvance = FT_MulFix( metrics->vertAdvance, y_scale );
metrics->vertBearingX = FT_MulFix( metrics->vertBearingX, x_scale );
metrics->vertBearingY = FT_MulFix( metrics->vertBearingY, y_scale );
}
/* compute the other metrics */
FT_Outline_Get_CBox( &glyph->root.outline, &cbox );
/* grid fit the bounding box if necessary */
if ( hinting )
{
cbox.xMin &= -64;
cbox.yMin &= -64;
cbox.xMax = ( cbox.xMax+63 ) & -64;
cbox.yMax = ( cbox.yMax+63 ) & -64;
}
metrics->width = cbox.xMax - cbox.xMin;
metrics->height = cbox.yMax - cbox.yMin;
metrics->horiBearingX = cbox.xMin;
metrics->horiBearingY = cbox.yMax;
}
}
Exit:
return error;
}
/* END */