| /**************************************************************************** |
| * |
| * ttmtx.c |
| * |
| * Load the metrics tables common to TTF and OTF fonts (body). |
| * |
| * Copyright (C) 2006-2020 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 <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 ) |
| { |
| 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 */ |
