diff options
Diffstat (limited to 'modules/freetype2/src/sfnt/ttmtx.c')
| -rw-r--r-- | modules/freetype2/src/sfnt/ttmtx.c | 338 |
1 files changed, 338 insertions, 0 deletions
diff --git a/modules/freetype2/src/sfnt/ttmtx.c b/modules/freetype2/src/sfnt/ttmtx.c new file mode 100644 index 0000000000..5e53e6dd4a --- /dev/null +++ b/modules/freetype2/src/sfnt/ttmtx.c @@ -0,0 +1,338 @@ +/**************************************************************************** + * + * ttmtx.c + * + * Load the metrics tables common to TTF and OTF fonts (body). + * + * Copyright (C) 2006-2023 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/internal/ftdebug.h> +#include <freetype/internal/ftstream.h> +#include <freetype/tttags.h> + +#ifdef TT_CONFIG_OPTION_GX_VAR_SUPPORT +#include <freetype/internal/services/svmetric.h> +#endif + +#include "ttmtx.h" + +#include "sferrors.h" + + + /* IMPORTANT: The TT_HoriHeader and TT_VertHeader structures should */ + /* be identical except for the names of their fields, */ + /* which are different. */ + /* */ + /* This ensures that `tt_face_load_hmtx' is able to read */ + /* both the horizontal and vertical headers. */ + + + /************************************************************************** + * + * 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 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. + */ + FT_LOCAL_DEF( FT_Error ) + tt_face_load_hmtx( TT_Face face, + FT_Stream stream, + FT_Bool vertical ) + { + FT_Error error; + FT_ULong tag, table_size; + FT_ULong* ptable_offset; + FT_ULong* ptable_size; + + + if ( vertical ) + { + tag = TTAG_vmtx; + ptable_offset = &face->vert_metrics_offset; + ptable_size = &face->vert_metrics_size; + } + else + { + tag = TTAG_hmtx; + ptable_offset = &face->horz_metrics_offset; + ptable_size = &face->horz_metrics_size; + } + + error = face->goto_table( face, tag, stream, &table_size ); + if ( error ) + goto Fail; + + *ptable_size = table_size; + *ptable_offset = FT_STREAM_POS(); + + Fail: + return error; + } + + + /************************************************************************** + * + * @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; + + static 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 + }; + + + if ( vertical ) + { + void *v = &face->vertical; + + + error = face->goto_table( face, TTAG_vhea, stream, 0 ); + if ( error ) + goto Fail; + + header = (TT_HoriHeader*)v; + } + else + { + error = face->goto_table( face, TTAG_hhea, stream, 0 ); + if ( error ) + goto Fail; + + header = &face->horizontal; + } + + if ( FT_STREAM_READ_FIELDS( metrics_header_fields, header ) ) + goto Fail; + + FT_TRACE3(( "Ascender: %5d\n", header->Ascender )); + FT_TRACE3(( "Descender: %5d\n", header->Descender )); + FT_TRACE3(( "number_Of_Metrics: %5u\n", header->number_Of_HMetrics )); + + header->long_metrics = NULL; + header->short_metrics = NULL; + + Fail: + return error; + } + + + /************************************************************************** + * + * @Function: + * tt_face_get_metrics + * + * @Description: + * Return the horizontal or vertical metrics in font units for a + * given glyph. The values are the left side bearing (top side + * bearing for vertical metrics) and advance width (advance height + * for vertical metrics). + * + * @Input: + * face :: + * A pointer to the TrueType face structure. + * + * vertical :: + * If set to TRUE, get vertical metrics. + * + * gindex :: + * The glyph index. + * + * @Output: + * abearing :: + * The bearing, either left side or top side. + * + * aadvance :: + * The advance width or advance height, depending on + * the `vertical' flag. + */ + FT_LOCAL_DEF( void ) + tt_face_get_metrics( TT_Face face, + FT_Bool vertical, + FT_UInt gindex, + FT_Short *abearing, + FT_UShort *aadvance ) + { + FT_Error error; + FT_Stream stream = face->root.stream; + TT_HoriHeader* header; + FT_ULong table_pos, table_size, table_end; + FT_UShort k; + +#ifdef TT_CONFIG_OPTION_GX_VAR_SUPPORT + FT_Service_MetricsVariations var = + (FT_Service_MetricsVariations)face->var; +#endif + + + if ( vertical ) + { + void* v = &face->vertical; + + + header = (TT_HoriHeader*)v; + table_pos = face->vert_metrics_offset; + table_size = face->vert_metrics_size; + } + else + { + header = &face->horizontal; + table_pos = face->horz_metrics_offset; + table_size = face->horz_metrics_size; + } + + table_end = table_pos + table_size; + + k = header->number_Of_HMetrics; + + if ( k > 0 ) + { + if ( gindex < (FT_UInt)k ) + { + table_pos += 4 * gindex; + if ( table_pos + 4 > table_end ) + goto NoData; + + if ( FT_STREAM_SEEK( table_pos ) || + FT_READ_USHORT( *aadvance ) || + FT_READ_SHORT( *abearing ) ) + goto NoData; + } + else + { + table_pos += 4 * ( k - 1 ); + if ( table_pos + 2 > table_end ) + goto NoData; + + if ( FT_STREAM_SEEK( table_pos ) || + FT_READ_USHORT( *aadvance ) ) + goto NoData; + + table_pos += 4 + 2 * ( gindex - k ); + if ( table_pos + 2 > table_end ) + *abearing = 0; + else + { + if ( FT_STREAM_SEEK( table_pos ) ) + *abearing = 0; + else + (void)FT_READ_SHORT( *abearing ); + } + } + } + else + { + NoData: + *abearing = 0; + *aadvance = 0; + } + +#ifdef TT_CONFIG_OPTION_GX_VAR_SUPPORT + if ( var && face->blend ) + { + FT_Face f = FT_FACE( face ); + FT_Int a = (FT_Int)*aadvance; + FT_Int b = (FT_Int)*abearing; + + + if ( vertical ) + { + if ( var->vadvance_adjust ) + var->vadvance_adjust( f, gindex, &a ); + if ( var->tsb_adjust ) + var->tsb_adjust( f, gindex, &b ); + } + else + { + if ( var->hadvance_adjust ) + var->hadvance_adjust( f, gindex, &a ); + if ( var->lsb_adjust ) + var->lsb_adjust( f, gindex, &b ); + } + + *aadvance = (FT_UShort)a; + *abearing = (FT_Short)b; + } +#endif + } + + +/* END */ |