ref: 1216e434cc9f1d2e79bfbd007516da314edec43b
dir: /src/truetype/ttgload.c/
/***************************************************************************/
/* */
/* ttgload.c */
/* */
/* TrueType Glyph Loader (body). */
/* */
/* Copyright 1996-1999 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 <freetype.h>
#include <ftdebug.h>
#include <ftcalc.h>
#include <ftstream.h>
#include <sfnt.h>
#include <ttgload.h>
#include <tttags.h>
#ifdef TT_CONFIG_OPTION_BYTECODE_INTERPRETER
#include <ttinterp.h>
#endif
/* required for the tracing mode */
#undef FT_COMPONENT
#define FT_COMPONENT trace_ttgload
/*************************************************************************/
/* */
/* Composite font flags. */
/* */
#define ARGS_ARE_WORDS 0x001
#define ARGS_ARE_XY_VALUES 0x002
#define ROUND_XY_TO_GRID 0x004
#define WE_HAVE_A_SCALE 0x008
/* reserved 0x010 */
#define MORE_COMPONENTS 0x020
#define WE_HAVE_AN_XY_SCALE 0x040
#define WE_HAVE_A_2X2 0x080
#define WE_HAVE_INSTR 0x100
#define USE_MY_METRICS 0x200
/*************************************************************************/
/* Returns the horizontal or vertical metrics in font units for a */
/* given glyph. The metrics are the left side bearing (resp. top */
/* side bearing) and advance width (resp. advance height). */
/* */
LOCAL_FUNC
void TT_Get_Metrics( TT_HoriHeader* header,
TT_UInt index,
TT_Short* bearing,
TT_UShort* advance )
{
TT_LongMetrics* longs_m;
TT_UShort k = header->number_Of_HMetrics;
if ( index < k )
{
longs_m = (TT_LongMetrics*)header->long_metrics + index;
*bearing = longs_m->bearing;
*advance = longs_m->advance;
}
else
{
*bearing = ((TT_ShortMetrics*)header->short_metrics)[index - k];
*advance = ((TT_LongMetrics*)header->long_metrics)[k - 1].advance;
}
}
/*************************************************************************/
/* Returns the horizontal metrics in font units for a given glyph. */
/* If `check' is true, take care of monospaced fonts by returning the */
/* advance width maximum. */
/* */
static
void Get_HMetrics( TT_Face face,
TT_UInt index,
TT_Bool check,
TT_Short* lsb,
TT_UShort* aw )
{
TT_Get_Metrics( &face->horizontal, index, lsb, aw );
if ( check && face->postscript.isFixedPitch )
*aw = face->horizontal.advance_Width_Max;
}
/*************************************************************************/
/* Returns the advance width table for a given pixel size if it is */
/* found in the font's `hdmx' table (if any). */
/* */
static
TT_Byte* Get_Advance_Widths( TT_Face face,
TT_UShort ppem )
{
TT_UShort n;
for ( n = 0; n < face->hdmx.num_records; n++ )
if ( face->hdmx.records[n].ppem == ppem )
return face->hdmx.records[n].widths;
return NULL;
}
#define cur_to_org( n, zone ) \
MEM_Copy( (zone)->org, (zone)->cur, n * sizeof ( TT_Vector ) )
#define org_to_cur( n, zone ) \
MEM_Copy( (zone)->cur, (zone)->org, n * sizeof ( TT_Vector ) )
/*************************************************************************/
/* Translates an array of coordinates. */
/* */
static
void translate_array( TT_UInt n,
TT_Vector* coords,
TT_Pos delta_x,
TT_Pos delta_y )
{
TT_UInt k;
if ( delta_x )
for ( k = 0; k < n; k++ )
coords[k].x += delta_x;
if ( delta_y )
for ( k = 0; k < n; k++ )
coords[k].y += delta_y;
}
/*************************************************************************/
/* Mounts one glyph zone on top of another. This is needed to */
/* assemble composite glyphs. */
/* */
static
void mount_zone( FT_GlyphZone* source,
FT_GlyphZone* target )
{
TT_UInt np;
TT_Int nc;
np = source->n_points;
nc = source->n_contours;
target->org = source->org + np;
target->cur = source->cur + np;
target->tags = source->tags + np;
target->contours = source->contours + nc;
target->n_points = 0;
target->n_contours = 0;
}
#undef IS_HINTED
#define IS_HINTED(flags) ((flags & FT_LOAD_NO_HINTING) == 0)
/*************************************************************************/
/* */
/* <Function> */
/* Load_Simple_Glyph */
/* */
/* <Description> */
/* Loads a simple (i.e, non-composite) glyph. This function is used */
/* for the `Load_Simple' state of TT_Load_Glyph(). All composite */
/* glyphs elements will be loaded with routine. */
/* */
static
TT_Error Load_Simple( TT_Loader* load,
TT_UInt byte_count,
TT_Int n_contours,
TT_Bool debug )
{
TT_Error error;
FT_Stream stream = load->stream;
FT_GlyphZone* zone = &load->zone;
TT_Face face = load->face;
TT_UShort n_ins;
TT_Int n, n_points;
/*********************************************************************/
/* simple check */
if ( n_contours > load->left_contours )
{
FT_TRACE0(( "ERROR: Glyph index %ld has %d contours > left %d\n",
load->glyph_index,
n_contours,
load->left_contours ));
return TT_Err_Too_Many_Contours;
}
/* preparing the execution context */
mount_zone( &load->base, zone );
/*********************************************************************/
/* reading the contours endpoints */
if ( ACCESS_Frame( byte_count ) )
return error;
for ( n = 0; n < n_contours; n++ )
zone->contours[n] = GET_UShort();
n_points = 0;
if ( n_contours > 0 )
n_points = zone->contours[n_contours - 1] + 1;
/*********************************************************************/
/* reading the bytecode instructions */
n_ins = GET_UShort();
if ( n_points > load->left_points )
{
FT_TRACE0(( "ERROR: Too many points in glyph %ld\n", load->glyph_index ));
error = TT_Err_Too_Many_Points;
goto Fail;
}
FT_TRACE4(( "Instructions size : %d\n", n_ins ));
if ( n_ins > face->max_profile.maxSizeOfInstructions )
{
FT_TRACE0(( "ERROR: Too many instructions!\n" ));
error = TT_Err_Too_Many_Ins;
goto Fail;
}
if (stream->cursor + n_ins > stream->limit)
{
FT_TRACE0(( "ERROR: Instruction count mismatch!\n" ));
error = TT_Err_Too_Many_Ins;
goto Fail;
}
#ifdef TT_CONFIG_OPTION_BYTECODE_INTERPRETER
if ( (load->load_flags & (FT_LOAD_NO_SCALE|FT_LOAD_NO_HINTING))==0 )
{
MEM_Copy( load->exec->glyphIns, stream->cursor, n_ins );
error = TT_Set_CodeRange( load->exec, tt_coderange_glyph,
load->exec->glyphIns, n_ins );
if (error) goto Fail;
}
#endif
stream->cursor += n_ins;
/*********************************************************************/
/* reading the point tags */
{
TT_Byte* flag = load->zone.tags;
TT_Byte* limit = flag + n_points;
TT_Byte c, count;
for (; flag < limit; flag++)
{
*flag = c = GET_Byte();
if ( c & 8 )
{
for ( count = GET_Byte(); count > 0; count-- )
*++flag = c;
}
}
}
/*********************************************************************/
/* reading the X coordinates */
{
TT_Vector* vec = zone->org;
TT_Vector* limit = vec + n_points;
TT_Byte* flag = zone->tags;
TT_Pos x = 0;
for ( ; vec < limit; vec++, flag++ )
{
TT_Pos y = 0;
if ( *flag & 2 )
{
y = GET_Byte();
if ((*flag & 16) == 0) y = -y;
}
else if ((*flag & 16) == 0)
y = GET_Short();
x += y;
vec->x = x;
}
}
/*********************************************************************/
/* reading the Y coordinates */
{
TT_Vector* vec = zone->org;
TT_Vector* limit = vec + n_points;
TT_Byte* flag = zone->tags;
TT_Pos x = 0;
for ( ; vec < limit; vec++, flag++ )
{
TT_Pos y = 0;
if ( *flag & 4 )
{
y = GET_Byte();
if ((*flag & 32) == 0) y = -y;
}
else if ((*flag & 32) == 0)
y = GET_Short();
x += y;
vec->y = x;
}
}
FORGET_Frame();
/*********************************************************************/
/* Add shadow points */
/* Now add the two shadow points at n and n + 1. */
/* We need the left side bearing and advance width. */
{
TT_Vector* pp1;
TT_Vector* pp2;
/* pp1 = xMin - lsb */
pp1 = zone->org + n_points;
pp1->x = load->bbox.xMin - load->left_bearing;
pp1->y = 0;
/* pp2 = pp1 + aw */
pp2 = pp1 + 1;
pp2->x = pp1->x + load->advance;
pp2->y = 0;
/* clear the touch tags */
for ( n = 0; n < n_points; n++ )
zone->tags[n] &= FT_Curve_Tag_On;
zone->tags[n_points ] = 0;
zone->tags[n_points + 1] = 0;
}
/* Note that we return two more points that are not */
/* part of the glyph outline. */
zone->n_points = n_points;
zone->n_contours = n_contours;
n_points += 2;
/*******************************************/
/* now eventually scale and hint the glyph */
if (load->load_flags & FT_LOAD_NO_SCALE)
{
/* no scaling, just copy the orig arrays into the cur ones */
org_to_cur( n_points, zone );
}
else
{
TT_Vector* vec = zone->org;
TT_Vector* limit = vec + n_points;
TT_Fixed x_scale = load->size->root.metrics.x_scale;
TT_Fixed y_scale = load->size->root.metrics.y_scale;
/* first scale the glyph points */
for (; vec < limit; vec++)
{
vec->x = FT_MulFix( vec->x, x_scale );
vec->y = FT_MulFix( vec->y, y_scale );
}
/* if hinting, round pp1, and shift the glyph accordingly */
if ( !IS_HINTED(load->load_flags) )
{
org_to_cur( n_points, zone );
}
else
{
TT_Pos x = zone->org[n_points-2].x;
x = ((x + 32) & -64) - x;
translate_array( n_points, zone->org, x, 0 );
org_to_cur( n_points, zone );
zone->cur[n_points-1].x = (zone->cur[n_points-1].x + 32) & -64;
#ifdef TT_CONFIG_OPTION_BYTECODE_INTERPRETER
/* now consider hinting */
if ( n_ins > 0 )
{
load->exec->is_composite = FALSE;
load->exec->pedantic_hinting = (TT_Bool)(load->load_flags & FT_LOAD_PEDANTIC);
load->exec->pts = *zone;
load->exec->pts.n_points += 2;
error = TT_Run_Context( load->exec, debug );
if ( error && load->exec->pedantic_hinting )
return error;
}
#endif
}
}
/* save glyph phantom points */
if ( !load->preserve_pps )
{
load->pp1 = zone->cur[n_points - 2];
load->pp2 = zone->cur[n_points - 1];
}
return TT_Err_Ok;
Fail:
FORGET_Frame();
return error;
}
/*************************************************************************/
/* */
/* <Function> */
/* load_truetype_glyph */
/* */
/* <Description> */
/* Loads a given truetype glyph. Handles composites and uses a */
/* TT_Loader object.. */
/* */
static
TT_Error load_truetype_glyph( TT_Loader* loader,
TT_UInt glyph_index )
{
FT_Stream stream = loader->stream;
TT_Error error;
TT_Face face = loader->face;
TT_ULong offset;
FT_SubGlyph subglyphs[ TT_MAX_SUBGLYPHS ];
TT_Int num_subglyphs = 0, contours_count;
TT_UInt index, num_points, num_contours, count;
TT_Fixed x_scale, y_scale;
TT_ULong ins_offset;
/* check glyph index */
index = glyph_index;
if ( index >= (TT_UInt)face->root.num_glyphs )
{
error = TT_Err_Invalid_Glyph_Index;
goto Fail;
}
loader->glyph_index = glyph_index;
num_contours = 0;
num_points = 0;
ins_offset = 0;
x_scale = 0x10000;
y_scale = 0x10000;
if ( (loader->load_flags & FT_LOAD_NO_SCALE)==0 )
{
x_scale = loader->size->root.metrics.x_scale;
y_scale = loader->size->root.metrics.y_scale;
}
/* get horizontal metrics */
{
TT_Short left_bearing;
TT_UShort advance_width;
Get_HMetrics( face, index,
(TT_Bool)!(loader->load_flags &
FT_LOAD_IGNORE_GLOBAL_ADVANCE_WIDTH),
&left_bearing,
&advance_width );
loader->left_bearing = left_bearing;
loader->advance = advance_width;
}
/* load glyph header */
offset = face->glyph_locations[index];
count = 0;
if (index < (TT_UInt)face->num_locations-1)
count = face->glyph_locations[index+1] - offset;
if (count == 0)
{
/* as described by Frederic Loyer, these are spaces, and */
/* not the unknown glyph. */
loader->bbox.xMin = 0;
loader->bbox.xMax = 0;
loader->bbox.yMin = 0;
loader->bbox.yMax = 0;
loader->pp1.x = 0;
loader->pp2.x = loader->advance;
if ( (loader->load_flags & FT_LOAD_NO_SCALE)==0 )
loader->pp2.x = FT_MulFix( loader->pp2.x, x_scale );
#ifdef TT_CONFIG_OPTION_BYTECODE_INTERPRETER
if (loader->exec)
loader->exec->glyphSize = 0;
#endif
goto Load_End;
}
offset = loader->glyf_offset + offset;
/* read first glyph header */
if ( FILE_Seek( offset ) || ACCESS_Frame( 10L ) )
goto Fail;
contours_count = GET_Short();
loader->bbox.xMin = GET_Short();
loader->bbox.yMin = GET_Short();
loader->bbox.xMax = GET_Short();
loader->bbox.yMax = GET_Short();
FORGET_Frame();
FT_TRACE6(( "Glyph %ld\n", index ));
FT_TRACE6(( " # of contours : %d\n", num_contours ));
FT_TRACE6(( " xMin: %4d xMax: %4d\n", loader->bbox.xMin,
loader->bbox.xMax ));
FT_TRACE6(( " yMin: %4d yMax: %4d\n", loader->bbox.yMin,
loader->bbox.yMax ));
FT_TRACE6(( "-" ));
count -= 10;
if ( contours_count > loader->left_contours )
{
FT_TRACE0(( "ERROR: Too many contours for glyph %ld\n", index ));
error = TT_Err_Too_Many_Contours;
goto Fail;
}
loader->pp1.x = loader->bbox.xMin - loader->left_bearing;
loader->pp1.y = 0;
loader->pp2.x = loader->pp1.x + loader->advance;
loader->pp2.y = 0;
if ((loader->load_flags & FT_LOAD_NO_SCALE)==0)
{
loader->pp1.x = FT_MulFix( loader->pp1.x, x_scale );
loader->pp2.x = FT_MulFix( loader->pp2.x, x_scale );
}
/*************************************************************************/
/*************************************************************************/
/*************************************************************************/
/**********************************************************************/
/* if it is a simple glyph, load it */
if (contours_count >= 0)
{
TT_UInt num_base_points;
#ifdef TT_CONFIG_OPTION_BYTECODE_INTERPRETER
error = Load_Simple( loader,
count,
contours_count,
(TT_Bool)( loader->size &&
loader->size->debug ) );
#else
error = Load_Simple( loader, count, contours_count, 0 );
#endif
if ( error )
goto Fail;
/* Note: We could have put the simple loader source there */
/* but the code is fat enough already :-) */
num_points = loader->zone.n_points;
num_contours = loader->zone.n_contours;
num_base_points = loader->base.n_points;
{
TT_UInt k;
for ( k = 0; k < num_contours; k++ )
loader->zone.contours[k] += num_base_points;
}
loader->base.n_points += num_points;
loader->base.n_contours += num_contours;
loader->zone.n_points = 0;
loader->zone.n_contours = 0;
loader->left_points -= num_points;
loader->left_contours -= num_contours;
}
/*************************************************************************/
/*************************************************************************/
/*************************************************************************/
/************************************************************************/
else /* otherwise, load a composite !! */
{
/* for each subglyph, read composite header */
FT_SubGlyph* subglyph = subglyphs;
if (ACCESS_Frame(count)) goto Fail;
num_subglyphs = 0;
do
{
TT_Fixed xx, xy, yy, yx;
subglyph->arg1 = subglyph->arg2 = 0;
subglyph->flags = GET_UShort();
subglyph->index = GET_UShort();
/* read arguments */
if (subglyph->flags & ARGS_ARE_WORDS)
{
subglyph->arg1 = GET_Short();
subglyph->arg2 = GET_Short();
}
else
{
subglyph->arg1 = GET_Char();
subglyph->arg2 = GET_Char();
}
/* read transform */
xx = yy = 0x10000;
xy = yx = 0;
if (subglyph->flags & WE_HAVE_A_SCALE)
{
xx = (TT_Fixed)GET_Short() << 2;
yy = xx;
}
else if (subglyph->flags & WE_HAVE_AN_XY_SCALE)
{
xx = (TT_Fixed)GET_Short() << 2;
yy = (TT_Fixed)GET_Short() << 2;
}
else if (subglyph->flags & WE_HAVE_A_2X2)
{
xx = (TT_Fixed)GET_Short() << 2;
xy = (TT_Fixed)GET_Short() << 2;
yx = (TT_Fixed)GET_Short() << 2;
yy = (TT_Fixed)GET_Short() << 2;
}
subglyph->transform.xx = xx;
subglyph->transform.xy = xy;
subglyph->transform.yx = yx;
subglyph->transform.yy = yy;
subglyph++;
num_subglyphs++;
if (num_subglyphs >= TT_MAX_SUBGLYPHS)
break;
}
while (subglyph[-1].flags & MORE_COMPONENTS);
#ifdef TT_CONFIG_OPTION_BYTECODE_INTERPRETER
{
/* we must undo the ACCESS_Frame in order to point to the */
/* composite instructions, if we find some .. */
/* we will process them later.. */
ins_offset = FILE_Pos() + stream->cursor - stream->limit;
}
#endif
FORGET_Frame();
/* if the flag FT_LOAD_NO_RECURSE is set, we return the subglyph */
/* "as is" in the glyph slot (the client application will be */
/* responsible for interpreting this data..) */
if ( loader->load_flags & FT_LOAD_NO_RECURSE )
{
FT_GlyphSlot glyph = loader->glyph;
/* reallocate subglyph array if necessary */
if (glyph->max_subglyphs < num_subglyphs)
{
FT_Memory memory = loader->face->root.memory;
if ( REALLOC_ARRAY( glyph->subglyphs, glyph->max_subglyphs,
num_subglyphs, FT_SubGlyph ) )
goto Fail;
glyph->max_subglyphs = num_subglyphs;
}
/* copy subglyph array */
MEM_Copy( glyph->subglyphs, subglyphs,
num_subglyphs*sizeof(FT_SubGlyph));
/* set up remaining glyph fields */
glyph->num_subglyphs = num_subglyphs;
glyph->format = ft_glyph_format_composite;
goto Load_End;
}
/*************************************************************************/
/*************************************************************************/
/*************************************************************************/
/*********************************************************************/
/* Now, read each subglyph independently.. */
{
TT_Int n, num_base_points, num_new_points;
subglyph = subglyphs;
for ( n = 0; n < num_subglyphs; n++, subglyph++ )
{
TT_Vector pp1, pp2;
TT_Pos x, y;
pp1 = loader->pp1;
pp2 = loader->pp2;
num_base_points = loader->base.n_points;
error = load_truetype_glyph( loader, subglyph->index );
if ( subglyph->flags & USE_MY_METRICS )
{
pp1 = loader->pp1;
pp2 = loader->pp2;
}
else
{
loader->pp1 = pp1;
loader->pp2 = pp2;
}
num_points = loader->base.n_points;
num_contours = loader->base.n_contours;
num_new_points = num_points - num_base_points;
/********************************************************/
/* now perform the transform required for this subglyph */
if ( subglyph->flags & ( WE_HAVE_A_SCALE |
WE_HAVE_AN_XY_SCALE |
WE_HAVE_A_2X2 ) )
{
TT_Vector* cur = loader->zone.cur;
TT_Vector* org = loader->zone.org;
TT_Vector* limit = cur + num_new_points;
for ( ; cur < limit; cur++, org++ )
{
TT_Pos nx, ny;
nx = FT_MulFix( cur->x, subglyph->transform.xx ) +
FT_MulFix( cur->y, subglyph->transform.yx );
ny = FT_MulFix( cur->x, subglyph->transform.xy ) +
FT_MulFix( cur->y, subglyph->transform.yy );
cur->x = nx;
cur->y = ny;
nx = FT_MulFix( org->x, subglyph->transform.xx ) +
FT_MulFix( org->y, subglyph->transform.yx );
ny = FT_MulFix( org->x, subglyph->transform.xy ) +
FT_MulFix( org->y, subglyph->transform.yy );
org->x = nx;
org->y = ny;
}
}
/* apply offset */
if ( !(subglyph->flags & ARGS_ARE_XY_VALUES) )
{
TT_Int k = subglyph->arg1;
TT_UInt l = subglyph->arg2;
if ( k >= num_base_points ||
l >= (TT_UInt)num_new_points )
{
error = TT_Err_Invalid_Composite;
goto Fail;
}
l += num_base_points;
x = loader->base.cur[k].x - loader->base.cur[l].x;
y = loader->base.cur[k].y - loader->base.cur[l].y;
}
else
{
x = subglyph->arg1;
y = subglyph->arg2;
if (!(loader->load_flags & FT_LOAD_NO_SCALE))
{
x = FT_MulFix( x, x_scale );
y = FT_MulFix( y, y_scale );
if ( subglyph->flags & ROUND_XY_TO_GRID )
{
x = (x + 32) & -64;
y = (y + 32) & -64;
}
}
}
translate_array( num_new_points, loader->zone.cur, x, y );
cur_to_org( num_new_points, &loader->zone );
}
/*************************************************************************/
/*************************************************************************/
/*************************************************************************/
/* we have finished loading all sub-glyphs, now, look for */
/* instructions for this composite !! */
#ifdef TT_CONFIG_OPTION_BYTECODE_INTERPRETER
subglyph--;
if (num_subglyphs > 0 && loader->exec && subglyph->flags & WE_HAVE_INSTR)
{
TT_UShort n_ins;
TT_ExecContext exec = loader->exec;
TT_UInt n_points = loader->base.n_points;
FT_GlyphZone* pts;
TT_Vector* pp1;
/* read size of instructions */
if ( FILE_Seek( ins_offset ) ||
READ_UShort(n_ins) ) goto Fail;
FT_TRACE4(( "Instructions size = %d\n", n_ins ));
/* check it */
if ( n_ins > face->max_profile.maxSizeOfInstructions )
{
FT_TRACE0(( "Too many instructions in composite glyph %ld\n",
subglyph->index ));
return TT_Err_Too_Many_Ins;
}
if (exec)
{
}
/* read the instructions */
if ( FILE_Read( exec->glyphIns, n_ins ) )
goto Fail;
error = TT_Set_CodeRange( exec,
tt_coderange_glyph,
exec->glyphIns,
n_ins );
if ( error ) goto Fail;
/* prepare the execution context */
exec->pts = loader->base;
pts = &exec->pts;
pts->n_points = num_points + 2;
pts->n_contours = num_contours;
/* add phantom points */
pp1 = pts->cur + num_points;
pp1[0] = loader->pp1;
pp1[1] = loader->pp2;
pts->tags[num_points + 1] = 0;
pts->tags[num_points + 2] = 0;
/* if hinting, round the phantom points */
if ( IS_HINTED(loader->load_flags) )
{
pp1[0].x = ((loader->pp1.x + 32) & -64);
pp1[1].x = ((loader->pp2.x + 32) & -64);
}
{
TT_UInt k;
for ( k = 0; k < n_points; k++ )
pts->tags[k] &= FT_Curve_Tag_On;
}
cur_to_org( n_points, pts );
/* now consider hinting */
if ( IS_HINTED(loader->load_flags) && n_ins > 0 )
{
exec->is_composite = TRUE;
exec->pedantic_hinting =
(TT_Bool)(loader->load_flags & FT_LOAD_PEDANTIC);
error = TT_Run_Context( exec, loader->size->debug );
if ( error && exec->pedantic_hinting )
goto Fail;
}
/* save glyph origin and advance points */
loader->pp1 = pp1[0];
loader->pp2 = pp1[1];
}
#endif
}
}
/*************************************************************************/
/*************************************************************************/
/*************************************************************************/
/*************************************************************************/
Load_End:
error = TT_Err_Ok;
Fail:
return error;
}
static
void compute_glyph_metrics( TT_Loader* loader,
TT_UInt glyph_index )
{
TT_UInt num_points = loader->base.n_points;
TT_UInt num_contours = loader->base.n_contours;
TT_BBox bbox;
TT_Face face = loader->face;
TT_Fixed x_scale, y_scale;
TT_GlyphSlot glyph = loader->glyph;
TT_Size size = loader->size;
/* when a simple glyph was loaded, the value of */
/* "base.n_points" and "base.n_contours" is 0, we must */
/* take those in the "zone" instead.. */
if ( num_points == 0 && num_contours == 0 )
{
num_points = loader->zone.n_points;
num_contours = loader->zone.n_contours;
}
x_scale = 0x10000;
y_scale = 0x10000;
if ( (loader->load_flags & FT_LOAD_NO_SCALE) == 0)
{
x_scale = size->root.metrics.x_scale;
y_scale = size->root.metrics.y_scale;
}
if ( glyph->format != ft_glyph_format_composite )
{
TT_UInt u;
for ( u = 0; u < num_points + 2; u++ )
{
glyph->outline.points[u] = loader->base.cur[u];
glyph->outline.tags [u] = loader->base.tags[u];
}
for ( u = 0; u < num_contours; u++ )
glyph->outline.contours[u] = loader->base.contours[u];
/* glyph->outline.second_pass = TRUE; */
glyph->outline.flags &= ~ft_outline_single_pass;
glyph->outline.n_points = num_points;
glyph->outline.n_contours = num_contours;
/* translate array so that (0,0) is the glyph's origin */
translate_array( (TT_UShort)(num_points + 2),
glyph->outline.points,
-loader->pp1.x,
0 );
FT_Outline_Get_CBox( &glyph->outline, &bbox );
if ( IS_HINTED(loader->load_flags) )
{
/* grid-fit the bounding box */
bbox.xMin &= -64;
bbox.yMin &= -64;
bbox.xMax = (bbox.xMax + 63) & -64;
bbox.yMax = (bbox.yMax + 63) & -64;
}
}
else
bbox = loader->bbox;
/* get the device-independent scaled horizontal metrics */
/* take care of fixed-pitch fonts... */
{
TT_Pos left_bearing;
TT_Pos advance;
left_bearing = loader->left_bearing;
advance = loader->advance;
/* the flag FT_LOAD_NO_ADVANCE_CHECK was introduced to */
/* correctly support DynaLab fonts, who have an incorrect */
/* "advance_Width_Max" field !! It is used, to my knowledge */
/* exclusively in the X-TrueType font server.. */
/* */
if ( face->postscript.isFixedPitch &&
(loader->load_flags & FT_LOAD_IGNORE_GLOBAL_ADVANCE_WIDTH) == 0 )
advance = face->horizontal.advance_Width_Max;
if ( !(loader->load_flags & FT_LOAD_NO_SCALE) )
{
left_bearing = FT_MulFix( left_bearing, x_scale );
advance = FT_MulFix( advance, x_scale );
}
glyph->metrics2.horiBearingX = left_bearing;
glyph->metrics2.horiAdvance = advance;
}
glyph->metrics.horiBearingX = bbox.xMin;
glyph->metrics.horiBearingY = bbox.yMax;
glyph->metrics.horiAdvance = loader->pp2.x - loader->pp1.x;
/* Now take care of vertical metrics. In the case where there is */
/* no vertical information within the font (relatively common), make */
/* up some metrics by `hand'... */
{
TT_Short top_bearing; /* vertical top side bearing (EM units) */
TT_UShort advance_height; /* vertical advance height (EM units) */
TT_Pos left; /* scaled vertical left side bearing */
TT_Pos Top; /* scaled original vertical top side bearing */
TT_Pos top; /* scaled vertical top side bearing */
TT_Pos advance; /* scaled vertical advance height */
/* Get the unscaled `tsb' and `ah' */
if ( face->vertical_info &&
face->vertical.number_Of_VMetrics > 0 )
{
/* Don't assume that both the vertical header and vertical */
/* metrics are present in the same font :-) */
TT_Get_Metrics( (TT_HoriHeader*)&face->vertical,
glyph_index,
&top_bearing,
&advance_height );
}
else
{
/* Make up the distances from the horizontal header.. */
/* NOTE: The OS/2 values are the only `portable' ones, */
/* which is why we use them, when there is an */
/* OS/2 table in the font. Otherwise, we use the */
/* values defined in the horizontal header.. */
/* */
/* NOTE2: The sTypoDescender is negative, which is why */
/* we compute the baseline-to-baseline distance */
/* here with: */
/* ascender - descender + linegap */
/* */
if ( face->os2.version != 0xFFFF )
{
top_bearing = face->os2.sTypoLineGap / 2;
advance_height = (TT_UShort)(face->os2.sTypoAscender -
face->os2.sTypoDescender +
face->os2.sTypoLineGap);
}
else
{
top_bearing = face->horizontal.Line_Gap / 2;
advance_height = (TT_UShort)(face->horizontal.Ascender +
face->horizontal.Descender +
face->horizontal.Line_Gap);
}
}
/* We must adjust the top_bearing value from the bounding box given
in the glyph header to te bounding box calculated with
TT_Get_Outline_BBox() */
/* scale the metrics */
if ( !(loader->load_flags & FT_LOAD_NO_SCALE) )
{
Top = FT_MulFix( top_bearing, y_scale );
top = FT_MulFix( top_bearing + loader->bbox.yMax, y_scale )
- bbox.yMax;
advance = FT_MulFix( advance_height, y_scale );
}
else
{
Top = top_bearing;
top = top_bearing + loader->bbox.yMax - bbox.yMax;
advance = advance_height;
}
glyph->metrics2.vertBearingY = Top;
glyph->metrics2.vertAdvance = advance;
/* XXX: for now, we have no better algorithm for the lsb, but it */
/* should work fine. */
/* */
left = ( bbox.xMin - bbox.xMax ) / 2;
/* grid-fit them if necessary */
if ( IS_HINTED(loader->load_flags) )
{
left &= -64;
top = (top + 63) & -64;
advance = (advance + 32) & -64;
}
glyph->metrics.vertBearingX = left;
glyph->metrics.vertBearingY = top;
glyph->metrics.vertAdvance = advance;
}
/* Adjust advance width to the value contained in the hdmx table. */
if ( !face->postscript.isFixedPitch && size &&
IS_HINTED(loader->load_flags) )
{
TT_Byte* widths = Get_Advance_Widths( face,
size->root.metrics.x_ppem );
if ( widths )
glyph->metrics.horiAdvance = widths[glyph_index] << 6;
}
/* drop-out mode is irrelevant, we always use mode 2 */
#if 0
#ifdef TT_CONFIG_OPTION_BYTECODE_INTERPRETER
if (loader->exec)
glyph->outline.dropout_mode = (TT_Char)loader->exec->GS.scan_type;
#else
glyph->outline.dropout_mode = 2;
#endif
#endif
/* set glyph dimensions */
glyph->metrics.width = bbox.xMax - bbox.xMin;
glyph->metrics.height = bbox.yMax - bbox.yMin;
}
LOCAL_FUNC
TT_Error TT_Load_Glyph( TT_Size size,
TT_GlyphSlot glyph,
TT_UShort glyph_index,
TT_UInt load_flags )
{
SFNT_Interface* sfnt;
TT_Face face;
FT_Stream stream;
FT_Memory memory;
TT_Error error;
TT_Loader loader;
FT_GlyphZone* zone;
face = (TT_Face)glyph->face;
sfnt = (SFNT_Interface*)face->sfnt;
stream = face->root.stream;
memory = face->root.memory;
error = 0;
if ( !size || (load_flags & FT_LOAD_NO_SCALE) ||
(load_flags & FT_LOAD_NO_RECURSE ))
{
size = NULL;
load_flags |= FT_LOAD_NO_SCALE |
FT_LOAD_NO_HINTING |
FT_LOAD_NO_BITMAP;
}
glyph->num_subglyphs = 0;
#ifdef TT_CONFIG_OPTION_EMBEDDED_BITMAPS
/*********************************************************************/
/* Try to load embedded bitmap if any */
if ( size && (load_flags & FT_LOAD_NO_BITMAP) == 0 && sfnt->load_sbits )
{
TT_SBit_Metrics metrics;
error = sfnt->load_sbit_image( face,
size->root.metrics.x_ppem,
size->root.metrics.y_ppem,
glyph_index,
stream,
&glyph->bitmap,
&metrics );
if ( !error )
{
glyph->outline.n_points = 0;
glyph->outline.n_contours = 0;
glyph->metrics.width = (TT_Pos)metrics.width << 6;
glyph->metrics.height = (TT_Pos)metrics.height << 6;
glyph->metrics.horiBearingX = (TT_Pos)metrics.horiBearingX << 6;
glyph->metrics.horiBearingY = (TT_Pos)metrics.horiBearingY << 6;
glyph->metrics.horiAdvance = (TT_Pos)metrics.horiAdvance << 6;
glyph->metrics.vertBearingX = (TT_Pos)metrics.vertBearingX << 6;
glyph->metrics.vertBearingY = (TT_Pos)metrics.vertBearingY << 6;
glyph->metrics.vertAdvance = (TT_Pos)metrics.vertAdvance << 6;
glyph->format = ft_glyph_format_bitmap;
return error;
}
}
#endif /* TT_CONFIG_OPTION_EMBEDDED_BITMAPS */
if ( load_flags & FT_LOAD_NO_OUTLINE )
return ( error ? error : TT_Err_Unavailable_Bitmap );
/* seek to the beginning of the glyph table. For Type 43 fonts */
/* the table might be accessed from a Postscript stream or something */
/* else... */
error = face->goto_table( face, TTAG_glyf, stream, 0 );
if (error)
{
FT_ERROR(( "TT.GLoad: could not access glyph table\n" ));
goto Exit;
}
MEM_Set( &loader, 0, sizeof(loader) );
/* update the glyph zone bounds */
zone = &((TT_Driver)face->root.driver)->zone;
error = FT_Update_GlyphZone( zone,
face->root.max_points,
face->root.max_contours );
if (error)
{
FT_ERROR(( "TT.GLoad: could not update loader glyph zone\n" ));
goto Exit;
}
loader.base = *zone;
loader.zone.n_points = 0;
loader.zone.n_contours = 0;
#ifdef TT_CONFIG_OPTION_BYTECODE_INTERPRETER
if ( size )
{
/* query new execution context */
loader.exec = size->debug ? size->context : TT_New_Context(face);
if ( !loader.exec )
return TT_Err_Could_Not_Find_Context;
TT_Load_Context( loader.exec, face, size );
/* load default graphics state - if needed */
if ( size->GS.instruct_control & 2 )
loader.exec->GS = tt_default_graphics_state;
}
#endif /* TT_CONFIG_OPTION_BYTECODE_INTERPRETER */
/* clear all outline flags, except the "owner" one */
glyph->outline.flags &= ft_outline_owner;
if (size && size->root.metrics.y_ppem < 24 )
glyph->outline.flags |= ft_outline_high_precision;
/************************************************************************/
/* let's initialise the rest of our loader now */
loader.left_points = face->root.max_points;
loader.left_contours = face->root.max_contours;
loader.load_flags = load_flags;
loader.face = face;
loader.size = size;
loader.glyph = glyph;
loader.stream = stream;
loader.glyf_offset = FILE_Pos();
#ifdef TT_CONFIG_OPTION_BYTECODE_INTERPRETER
/* when the cvt program has disabled hinting, the argument */
/* is ignored. */
if ( size && (size->GS.instruct_control & 1) )
loader.load_flags |= FT_LOAD_NO_HINTING;
#endif
/* Main loading loop */
glyph->format = ft_glyph_format_outline;
error = load_truetype_glyph( &loader, glyph_index );
if (!error)
compute_glyph_metrics( &loader, glyph_index );
#ifdef TT_CONFIG_OPTION_BYTECODE_INTERPRETER
if ( !size || !size->debug )
TT_Done_Context( loader.exec );
#endif
Exit:
return error;
}
/* END */