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freetype2/src/sfnt/ttmtx.c

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Clean up the SFNT_Interface. Table loading functions are now named after the tables' tags; `hdmx' is TrueType-specific and thus the code is moved to the truetype module; `get_metrics' is moved here from the truetype module so that the code can be shared with the cff module. This pass involves no real changes. That is, the code is moved verbatim mostly. The only exception is the return value of `tt_face_get_metrics'. * include/freetype/internal/sfnt.h, src/sfnt/rules.mk, src/sfnt/sfdriver.c, src/sfnt/sfnt.c, src/sfnt/sfobjs.c, src/sfnt/ttload.c, src/sfnt/ttload.h, src/sfnt/ttsbit.c, src/sfnt/ttsbit.h, src/sfnt/ttsbit0.c: Clean up the SFNT_Interface. * src/sfnt/ttmtx.c, src/sfnt/ttmtx.h: Metrics-related tables' loading and parsing code is moved here. Move `tt_face_get_metrics' here from the truetype module. The return value is changed from `void' to `FT_Error'. * include/freetype/internal/fttrace.h: New trace: ttmtx. * src/truetype/ttpload.c, src/truetype/ttpload.h: `hdmx' loading and parsing code is moved here. New function `tt_face_load_prep' splitted from `tt_face_load_fpgm'. `tt_face_load_fpgm' returns `FT_Err_Ok' if `fpgm' doesn't exist. * src/cff/cffgload.c, src/cff/cffobjs.c: Update. * src/truetype/ttgload.c, src/truetype/ttobjs.c: Update.
2006-02-14 07:40:10 +01:00
/***************************************************************************/
/* */
/* ttmtx.c */
/* */
/* Load the metrics tables common to TTF and OTF fonts (body). */
/* */
/* Copyright 2006 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_INTERNAL_DEBUG_H
#include FT_INTERNAL_STREAM_H
#include FT_TRUETYPE_TAGS_H
#include "ttmtx.h"
#include "sferrors.h"
/*************************************************************************/
/* */
/* 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_ttmtx
/*************************************************************************/
/* */
/* <Function> */
/* tt_face_load_hmtx */
/* */
/* <Description> */
/* Load the `hmtx' or `vmtx' table into a face object. */
/* */
/* <Input> */
/* face :: A handle to the target face object. */
/* */
/* stream :: The input stream. */
/* */
/* vertical :: A boolean flag. If set, load `vmtx'. */
/* */
/* <Return> */
/* FreeType error code. 0 means success. */
/* */
#ifdef FT_OPTIMIZE_MEMORY
static FT_Error
tt_face_load_hmtx( TT_Face face,
FT_Stream stream,
FT_Bool vertical )
{
FT_Error error;
FT_ULong table_size;
FT_Byte** ptable;
FT_ULong* ptable_size;
FT_TRACE2(( "TT_Load_%s_Metrics: %08p\n", vertical ? "Vertical"
: "Horizontal",
face ));
if ( vertical )
{
ptable = &face->vert_metrics;
ptable_size = &face->vert_metrics_size;
/* The table is optional, quit silently if it wasn't found. */
/* */
/* XXX: Some fonts have a valid vertical header with a non-null */
/* `number_of_VMetrics' fields, but no corresponding `vmtx' */
/* table to get the metrics from (e.g. mingliu). */
/* */
/* For safety, we set the field to 0! */
/* */
error = face->goto_table( face, TTAG_vmtx, stream, &table_size );
if ( error )
{
/* Set number_Of_VMetrics to 0! */
FT_TRACE2(( " no vertical header in file.\n" ));
error = SFNT_Err_Ok;
goto Exit;
}
}
else
{
ptable = &face->horz_metrics;
ptable_size = &face->horz_metrics_size;
error = face->goto_table( face, TTAG_hmtx, stream, &table_size );
if ( error )
{
#ifdef FT_CONFIG_OPTION_INCREMENTAL
/* If this is an incrementally loaded font and there are */
/* overriding metrics, tolerate a missing `hmtx' table. */
if ( face->root.internal->incremental_interface &&
face->root.internal->incremental_interface->funcs->
get_glyph_metrics )
{
face->horizontal.number_Of_HMetrics = 0;
error = SFNT_Err_Ok;
goto Exit;
}
#endif
FT_ERROR(( " no horizontal metrics in file!\n" ));
error = SFNT_Err_Hmtx_Table_Missing;
goto Exit;
}
}
if ( FT_FRAME_EXTRACT( table_size, *ptable ) )
goto Exit;
*ptable_size = table_size;
Exit:
return error;
}
#else /* !OPTIMIZE_MEMORY */
static FT_Error
tt_face_load_hmtx( TT_Face face,
FT_Stream stream,
FT_Bool vertical )
{
FT_Error error;
FT_Memory memory = stream->memory;
FT_ULong table_len;
FT_Long num_shorts, num_longs, num_shorts_checked;
TT_LongMetrics * longs;
TT_ShortMetrics** shorts;
FT_TRACE2(( "TT_Load_%s_Metrics: %08p\n", vertical ? "Vertical"
: "Horizontal",
face ));
if ( vertical )
{
/* The table is optional, quit silently if it wasn't found. */
/* */
/* XXX: Some fonts have a valid vertical header with a non-null */
/* `number_of_VMetrics' fields, but no corresponding `vmtx' */
/* table to get the metrics from (e.g. mingliu). */
/* */
/* For safety, we set the field to 0! */
/* */
error = face->goto_table( face, TTAG_vmtx, stream, &table_len );
if ( error )
{
/* Set number_Of_VMetrics to 0! */
FT_TRACE2(( " no vertical header in file.\n" ));
face->vertical.number_Of_VMetrics = 0;
error = SFNT_Err_Ok;
goto Exit;
}
num_longs = face->vertical.number_Of_VMetrics;
longs = (TT_LongMetrics *)&face->vertical.long_metrics;
shorts = (TT_ShortMetrics**)&face->vertical.short_metrics;
}
else
{
error = face->goto_table( face, TTAG_hmtx, stream, &table_len );
if ( error )
{
#ifdef FT_CONFIG_OPTION_INCREMENTAL
/* If this is an incrementally loaded font and there are */
/* overriding metrics, tolerate a missing `hmtx' table. */
if ( face->root.internal->incremental_interface &&
face->root.internal->incremental_interface->funcs->
get_glyph_metrics )
{
face->horizontal.number_Of_HMetrics = 0;
error = SFNT_Err_Ok;
goto Exit;
}
#endif
FT_ERROR(( " no horizontal metrics in file!\n" ));
error = SFNT_Err_Hmtx_Table_Missing;
goto Exit;
}
num_longs = face->horizontal.number_Of_HMetrics;
longs = (TT_LongMetrics *)&face->horizontal.long_metrics;
shorts = (TT_ShortMetrics**)&face->horizontal.short_metrics;
}
/* never trust derived values */
num_shorts = face->max_profile.numGlyphs - num_longs;
num_shorts_checked = ( table_len - num_longs * 4L ) / 2;
if ( num_shorts < 0 )
{
FT_ERROR(( "TT_Load_%s_Metrics: more metrics than glyphs!\n",
vertical ? "Vertical"
: "Horizontal" ));
/* Adobe simply ignores this problem. So we shall do the same. */
#if 0
error = vertical ? SFNT_Err_Invalid_Vert_Metrics
: SFNT_Err_Invalid_Horiz_Metrics;
goto Exit;
#else
num_shorts = 0;
#endif
}
if ( FT_QNEW_ARRAY( *longs, num_longs ) ||
FT_QNEW_ARRAY( *shorts, num_shorts ) )
goto Exit;
if ( FT_FRAME_ENTER( table_len ) )
goto Exit;
{
TT_LongMetrics cur = *longs;
TT_LongMetrics limit = cur + num_longs;
for ( ; cur < limit; cur++ )
{
cur->advance = FT_GET_USHORT();
cur->bearing = FT_GET_SHORT();
}
}
/* do we have an inconsistent number of metric values? */
{
TT_ShortMetrics* cur = *shorts;
TT_ShortMetrics* limit = cur +
FT_MIN( num_shorts, num_shorts_checked );
for ( ; cur < limit; cur++ )
*cur = FT_GET_SHORT();
/* We fill up the missing left side bearings with the */
/* last valid value. Since this will occur for buggy CJK */
/* fonts usually only, nothing serious will happen. */
if ( num_shorts > num_shorts_checked && num_shorts_checked > 0 )
{
FT_Short val = (*shorts)[num_shorts_checked - 1];
limit = *shorts + num_shorts;
for ( ; cur < limit; cur++ )
*cur = val;
}
}
FT_FRAME_EXIT();
FT_TRACE2(( "loaded\n" ));
Exit:
return error;
}
#endif /* !FT_OPTIMIZE_METRICS */
/*************************************************************************/
/* */
/* <Function> */
/* tt_face_load_hhea */
/* */
/* <Description> */
/* Load the `hhea' or 'vhea' table into a face object. */
/* */
/* <Input> */
/* face :: A handle to the target face object. */
/* */
/* stream :: The input stream. */
/* */
/* vertical :: A boolean flag. If set, load `vhea'. */
/* */
/* <Return> */
/* FreeType error code. 0 means success. */
/* */
FT_LOCAL_DEF( FT_Error )
tt_face_load_hhea( TT_Face face,
FT_Stream stream,
FT_Bool vertical )
{
FT_Error error;
TT_HoriHeader* header;
const FT_Frame_Field metrics_header_fields[] =
{
#undef FT_STRUCTURE
#define FT_STRUCTURE TT_HoriHeader
FT_FRAME_START( 36 ),
FT_FRAME_ULONG ( Version ),
FT_FRAME_SHORT ( Ascender ),
FT_FRAME_SHORT ( Descender ),
FT_FRAME_SHORT ( Line_Gap ),
FT_FRAME_USHORT( advance_Width_Max ),
FT_FRAME_SHORT ( min_Left_Side_Bearing ),
FT_FRAME_SHORT ( min_Right_Side_Bearing ),
FT_FRAME_SHORT ( xMax_Extent ),
FT_FRAME_SHORT ( caret_Slope_Rise ),
FT_FRAME_SHORT ( caret_Slope_Run ),
FT_FRAME_SHORT ( caret_Offset ),
FT_FRAME_SHORT ( Reserved[0] ),
FT_FRAME_SHORT ( Reserved[1] ),
FT_FRAME_SHORT ( Reserved[2] ),
FT_FRAME_SHORT ( Reserved[3] ),
FT_FRAME_SHORT ( metric_Data_Format ),
FT_FRAME_USHORT( number_Of_HMetrics ),
FT_FRAME_END
};
FT_TRACE2(( vertical ? "Vertical header " : "Horizontal header " ));
if ( vertical )
{
face->vertical_info = 0;
/* The vertical header table is optional, so return quietly if */
/* we don't find it. */
error = face->goto_table( face, TTAG_vhea, stream, 0 );
if ( error )
{
error = SFNT_Err_Ok;
goto Exit;
}
face->vertical_info = 1;
header = (TT_HoriHeader*)&face->vertical;
}
else
{
/* The horizontal header is mandatory for most fonts; return */
/* an error if we don't find it. */
error = face->goto_table( face, TTAG_hhea, stream, 0 );
if ( error )
{
error = SFNT_Err_Horiz_Header_Missing;
/* No `hhea' table necessary for SFNT Mac fonts. */
if ( face->format_tag == TTAG_true )
{
FT_TRACE2(( "missing. This is an SFNT Mac font.\n"));
error = SFNT_Err_Ok;
}
goto Exit;
}
header = &face->horizontal;
}
if ( FT_STREAM_READ_FIELDS( metrics_header_fields, header ) )
goto Exit;
header->long_metrics = NULL;
header->short_metrics = NULL;
FT_TRACE2(( "loaded\n" ));
/* Now try to load the corresponding metrics */
error = tt_face_load_hmtx( face, stream, vertical );
Exit:
return error;
}
/*************************************************************************/
/* */
/* <Function> */
/* tt_face_get_metrics */
/* */
/* <Description> */
/* 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). */
/* */
/* <Input> */
/* header :: A pointer to either the horizontal or vertical metrics */
/* structure. */
/* */
/* idx :: The glyph index. */
/* */
/* <Output> */
/* bearing :: The bearing, either left side or top side. */
/* */
/* advance :: The advance width resp. advance height. */
/* */
/* <Note> */
/* This function will much probably move to another component in the */
/* near future, but I haven't decided which yet. */
/* */
#ifdef FT_OPTIMIZE_MEMORY
FT_LOCAL_DEF( FT_Error )
tt_face_get_metrics( TT_Face face,
FT_Bool vertical,
FT_UInt gindex,
FT_Short *abearing,
FT_UShort *aadvance )
{
TT_HoriHeader* header;
FT_Byte* p;
FT_Byte* limit;
FT_UShort k;
if ( vertical )
{
header = (TT_HoriHeader*)&face->vertical;
p = face->vert_metrics;
limit = p + face->vert_metrics_size;
}
else
{
header = &face->horizontal;
p = face->horz_metrics;
limit = p + face->horz_metrics_size;
}
k = header->number_Of_HMetrics;
if ( k > 0 )
{
if ( gindex < (FT_UInt)k )
{
p += 4 * gindex;
if ( p + 4 > limit )
goto NoData;
*aadvance = FT_NEXT_USHORT( p );
*abearing = FT_NEXT_SHORT( p );
}
else
{
p += 4 * ( k - 1 );
if ( p + 4 > limit )
goto NoData;
*aadvance = FT_NEXT_USHORT( p );
p += 2 + 2 * ( gindex - k );
if ( p + 2 > limit )
*abearing = 0;
else
*abearing = FT_PEEK_SHORT( p );
}
}
else
{
NoData:
*abearing = 0;
*aadvance = 0;
}
return SFNT_Err_Ok;
}
#else /* !FT_OPTIMIZE_MEMORY */
FT_LOCAL_DEF( FT_Error )
tt_face_get_metrics( TT_Face face,
FT_Bool vertical,
FT_UInt gindex,
FT_Short* abearing,
FT_UShort* aadvance )
{
TT_HoriHeader* header = vertical ? (TT_HoriHeader*)&face->vertical
: &face->horizontal;
TT_LongMetrics longs_m;
FT_UShort k = header->number_Of_HMetrics;
if ( k == 0 )
{
*abearing = *aadvance = 0;
return SFNT_Err_Ok;
}
if ( gindex < (FT_UInt)k )
{
longs_m = (TT_LongMetrics)header->long_metrics + gindex;
*abearing = longs_m->bearing;
*aadvance = longs_m->advance;
}
else
{
*abearing = ((TT_ShortMetrics*)header->short_metrics)[gindex - k];
*aadvance = ((TT_LongMetrics)header->long_metrics)[k - 1].advance;
}
return SFNT_Err_Ok;
}
#endif /* !FT_OPTIMIZE_MEMORY */
/* END */