ref: d0ab3a0dd8f6355b3603d0fb04043a9ae867639b
dir: /libfreetype/ttgload.c/
/***************************************************************************/ /* */ /* ttgload.c */ /* */ /* TrueType Glyph Loader (body). */ /* */ /* Copyright 1996-2001, 2002 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_CALC_H #include FT_INTERNAL_STREAM_H #include FT_INTERNAL_SFNT_H #include FT_TRUETYPE_TAGS_H #include FT_OUTLINE_H #include "ttgload.h" #include "tterrors.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_ttgload /*************************************************************************/ /* */ /* Composite font flags. */ /* */ #define ARGS_ARE_WORDS 0x0001 #define ARGS_ARE_XY_VALUES 0x0002 #define ROUND_XY_TO_GRID 0x0004 #define WE_HAVE_A_SCALE 0x0008 /* reserved 0x0010 */ #define MORE_COMPONENTS 0x0020 #define WE_HAVE_AN_XY_SCALE 0x0040 #define WE_HAVE_A_2X2 0x0080 #define WE_HAVE_INSTR 0x0100 #define USE_MY_METRICS 0x0200 #define OVERLAP_COMPOUND 0x0400 #define SCALED_COMPONENT_OFFSET 0x0800 #define UNSCALED_COMPONENT_OFFSET 0x1000 /*************************************************************************/ /* */ /* <Function> */ /* TT_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. */ /* */ FT_LOCAL_DEF( void ) TT_Get_Metrics( TT_HoriHeader* header, FT_UInt idx, FT_Short* bearing, FT_UShort* advance ) { TT_LongMetrics longs_m; FT_UShort k = header->number_Of_HMetrics; if ( k == 0 ) { *bearing = *advance = 0; return; } if ( idx < (FT_UInt)k ) { longs_m = (TT_LongMetrics )header->long_metrics + idx; *bearing = longs_m->bearing; *advance = longs_m->advance; } else { *bearing = ((TT_ShortMetrics*)header->short_metrics)[idx - 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, FT_UInt idx, FT_Bool check, FT_Short* lsb, FT_UShort* aw ) { TT_Get_Metrics( &face->horizontal, idx, 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 FT_Byte* Get_Advance_Widths( TT_Face face, FT_UShort ppem ) { FT_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 ) \ FT_MEM_COPY( (zone)->org, (zone)->cur, (n) * sizeof ( FT_Vector ) ) #define org_to_cur( n, zone ) \ FT_MEM_COPY( (zone)->cur, (zone)->org, (n) * sizeof ( FT_Vector ) ) /*************************************************************************/ /* */ /* Translates an array of coordinates. */ /* */ static void translate_array( FT_UInt n, FT_Vector* coords, FT_Pos delta_x, FT_Pos delta_y ) { FT_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; } static void tt_prepare_zone( TT_GlyphZone zone, FT_GlyphLoad load, FT_UInt start_point, FT_UInt start_contour ) { zone->n_points = (FT_UShort)( load->outline.n_points - start_point ); zone->n_contours = (FT_Short) ( load->outline.n_contours - start_contour ); zone->org = load->extra_points + start_point; zone->cur = load->outline.points + start_point; zone->tags = (FT_Byte*)load->outline.tags + start_point; zone->contours = (FT_UShort*)load->outline.contours + start_contour; } #undef IS_HINTED #define IS_HINTED( flags ) ( ( flags & FT_LOAD_NO_HINTING ) == 0 ) /*************************************************************************/ /* */ /* The following functions are used by default with TrueType fonts. */ /* However, they can be replaced by alternatives if we need to support */ /* TrueType-compressed formats (like MicroType) in the future. */ /* */ /*************************************************************************/ FT_CALLBACK_DEF( FT_Error ) TT_Access_Glyph_Frame( TT_Loader loader, FT_UInt glyph_index, FT_ULong offset, FT_UInt byte_count ) { FT_Error error; FT_Stream stream = loader->stream; /* for non-debug mode */ FT_UNUSED( glyph_index ); FT_TRACE5(( "Glyph %ld\n", glyph_index )); /* the following line sets the `error' variable through macros! */ if ( FT_STREAM_SEEK( offset ) || FT_FRAME_ENTER( byte_count ) ) return error; return TT_Err_Ok; } FT_CALLBACK_DEF( void ) TT_Forget_Glyph_Frame( TT_Loader loader ) { FT_Stream stream = loader->stream; FT_FRAME_EXIT(); } FT_CALLBACK_DEF( FT_Error ) TT_Load_Glyph_Header( TT_Loader loader ) { FT_Stream stream = loader->stream; FT_Int byte_len = loader->byte_len - 10; if ( byte_len < 0 ) return TT_Err_Invalid_Outline; loader->n_contours = FT_GET_SHORT(); loader->bbox.xMin = FT_GET_SHORT(); loader->bbox.yMin = FT_GET_SHORT(); loader->bbox.xMax = FT_GET_SHORT(); loader->bbox.yMax = FT_GET_SHORT(); FT_TRACE5(( " # of contours: %d\n", loader->n_contours )); FT_TRACE5(( " xMin: %4d xMax: %4d\n", loader->bbox.xMin, loader->bbox.xMax )); FT_TRACE5(( " yMin: %4d yMax: %4d\n", loader->bbox.yMin, loader->bbox.yMax )); loader->byte_len = byte_len; return TT_Err_Ok; } FT_CALLBACK_DEF( FT_Error ) TT_Load_Simple_Glyph( TT_Loader load ) { FT_Error error; FT_Stream stream = load->stream; FT_GlyphLoader gloader = load->gloader; FT_Int n_contours = load->n_contours; FT_Outline* outline; TT_Face face = (TT_Face)load->face; TT_GlyphSlot slot = (TT_GlyphSlot)load->glyph; FT_UShort n_ins; FT_Int n, n_points; FT_Int byte_len = load->byte_len; /* reading the contours endpoints & number of points */ { short* cur = gloader->current.outline.contours; short* limit = cur + n_contours; /* check space for contours array + instructions count */ byte_len -= 2 * ( n_contours + 1 ); if ( byte_len < 0 ) goto Invalid_Outline; for ( ; cur < limit; cur++ ) cur[0] = FT_GET_USHORT(); n_points = 0; if ( n_contours > 0 ) n_points = cur[-1] + 1; error = FT_GlyphLoader_CheckPoints( gloader, n_points + 2, 0 ); if ( error ) goto Fail; /* we'd better check the contours table right now */ outline = &gloader->current.outline; for ( cur = outline->contours + 1; cur < limit; cur++ ) if ( cur[-1] >= cur[0] ) goto Invalid_Outline; } /* reading the bytecode instructions */ slot->control_len = 0; slot->control_data = 0; n_ins = FT_GET_USHORT(); FT_TRACE5(( " Instructions size: %d\n", n_ins )); if ( n_ins > face->max_profile.maxSizeOfInstructions ) { FT_TRACE0(( "TT_Load_Simple_Glyph: Too many instructions!\n" )); error = TT_Err_Too_Many_Hints; goto Fail; } byte_len -= n_ins; if ( byte_len < 0 ) { FT_TRACE0(( "TT_Load_Simple_Glyph: Instruction count mismatch!\n" )); error = TT_Err_Too_Many_Hints; goto Fail; } #ifdef TT_CONFIG_OPTION_BYTECODE_INTERPRETER if ( ( load->load_flags & ( FT_LOAD_NO_SCALE | FT_LOAD_NO_HINTING ) ) == 0 && load->instructions ) { slot->control_len = n_ins; slot->control_data = load->instructions; FT_MEM_COPY( load->instructions, stream->cursor, n_ins ); } #endif /* TT_CONFIG_OPTION_BYTECODE_INTERPRETER */ stream->cursor += n_ins; /* reading the point tags */ { FT_Byte* flag = (FT_Byte*)outline->tags; FT_Byte* limit = flag + n_points; FT_Byte c, count; while ( flag < limit ) { if ( --byte_len < 0 ) goto Invalid_Outline; *flag++ = c = FT_GET_BYTE(); if ( c & 8 ) { if ( --byte_len < 0 ) goto Invalid_Outline; count = FT_GET_BYTE(); if ( flag + count > limit ) goto Invalid_Outline; for ( ; count > 0; count-- ) *flag++ = c; } } /* check that there is enough room to load the coordinates */ for ( flag = (FT_Byte*)outline->tags; flag < limit; flag++ ) { if ( *flag & 2 ) byte_len -= 1; else if ( ( *flag & 16 ) == 0 ) byte_len -= 2; if ( *flag & 4 ) byte_len -= 1; else if ( ( *flag & 32 ) == 0 ) byte_len -= 2; } if ( byte_len < 0 ) goto Invalid_Outline; } /* reading the X coordinates */ { FT_Vector* vec = outline->points; FT_Vector* limit = vec + n_points; FT_Byte* flag = (FT_Byte*)outline->tags; FT_Pos x = 0; for ( ; vec < limit; vec++, flag++ ) { FT_Pos y = 0; if ( *flag & 2 ) { y = FT_GET_BYTE(); if ( ( *flag & 16 ) == 0 ) y = -y; } else if ( ( *flag & 16 ) == 0 ) y = FT_GET_SHORT(); x += y; vec->x = x; } } /* reading the Y coordinates */ { FT_Vector* vec = gloader->current.outline.points; FT_Vector* limit = vec + n_points; FT_Byte* flag = (FT_Byte*)outline->tags; FT_Pos x = 0; for ( ; vec < limit; vec++, flag++ ) { FT_Pos y = 0; if ( *flag & 4 ) { y = FT_GET_BYTE(); if ( ( *flag & 32 ) == 0 ) y = -y; } else if ( ( *flag & 32 ) == 0 ) y = FT_GET_SHORT(); x += y; vec->y = x; } } /* clear the touch tags */ for ( n = 0; n < n_points; n++ ) outline->tags[n] &= FT_CURVE_TAG_ON; outline->n_points = (FT_UShort)n_points; outline->n_contours = (FT_Short) n_contours; load->byte_len = byte_len; Fail: return error; Invalid_Outline: error = TT_Err_Invalid_Outline; goto Fail; } FT_CALLBACK_DEF( FT_Error ) TT_Load_Composite_Glyph( TT_Loader loader ) { FT_Error error; FT_Stream stream = loader->stream; FT_GlyphLoader gloader = loader->gloader; FT_SubGlyph subglyph; FT_UInt num_subglyphs; FT_Int byte_len = loader->byte_len; num_subglyphs = 0; do { FT_Fixed xx, xy, yy, yx; /* check that we can load a new subglyph */ error = FT_GlyphLoader_CheckSubGlyphs( gloader, num_subglyphs + 1 ); if ( error ) goto Fail; /* check space */ byte_len -= 4; if ( byte_len < 0 ) goto Invalid_Composite; subglyph = gloader->current.subglyphs + num_subglyphs; subglyph->arg1 = subglyph->arg2 = 0; subglyph->flags = FT_GET_USHORT(); subglyph->index = FT_GET_USHORT(); /* check space */ byte_len -= 2; if ( subglyph->flags & ARGS_ARE_WORDS ) byte_len -= 2; if ( subglyph->flags & WE_HAVE_A_SCALE ) byte_len -= 2; else if ( subglyph->flags & WE_HAVE_AN_XY_SCALE ) byte_len -= 4; else if ( subglyph->flags & WE_HAVE_A_2X2 ) byte_len -= 8; if ( byte_len < 0 ) goto Invalid_Composite; /* read arguments */ if ( subglyph->flags & ARGS_ARE_WORDS ) { subglyph->arg1 = FT_GET_SHORT(); subglyph->arg2 = FT_GET_SHORT(); } else { subglyph->arg1 = FT_GET_CHAR(); subglyph->arg2 = FT_GET_CHAR(); } /* read transform */ xx = yy = 0x10000L; xy = yx = 0; if ( subglyph->flags & WE_HAVE_A_SCALE ) { xx = (FT_Fixed)FT_GET_SHORT() << 2; yy = xx; } else if ( subglyph->flags & WE_HAVE_AN_XY_SCALE ) { xx = (FT_Fixed)FT_GET_SHORT() << 2; yy = (FT_Fixed)FT_GET_SHORT() << 2; } else if ( subglyph->flags & WE_HAVE_A_2X2 ) { xx = (FT_Fixed)FT_GET_SHORT() << 2; yx = (FT_Fixed)FT_GET_SHORT() << 2; xy = (FT_Fixed)FT_GET_SHORT() << 2; yy = (FT_Fixed)FT_GET_SHORT() << 2; } subglyph->transform.xx = xx; subglyph->transform.xy = xy; subglyph->transform.yx = yx; subglyph->transform.yy = yy; num_subglyphs++; } while ( subglyph->flags & MORE_COMPONENTS ); gloader->current.num_subglyphs = num_subglyphs; #ifdef TT_CONFIG_OPTION_BYTECODE_INTERPRETER { /* we must undo the FT_FRAME_ENTER in order to point to the */ /* composite instructions, if we find some. */ /* we will process them later... */ /* */ loader->ins_pos = (FT_ULong)( FT_STREAM_POS() + stream->cursor - stream->limit ); } #endif loader->byte_len = byte_len; Fail: return error; Invalid_Composite: error = TT_Err_Invalid_Composite; goto Fail; } FT_LOCAL_DEF( void ) TT_Init_Glyph_Loading( TT_Face face ) { face->access_glyph_frame = TT_Access_Glyph_Frame; face->read_glyph_header = TT_Load_Glyph_Header; face->read_simple_glyph = TT_Load_Simple_Glyph; face->read_composite_glyph = TT_Load_Composite_Glyph; face->forget_glyph_frame = TT_Forget_Glyph_Frame; } /*************************************************************************/ /* */ /* <Function> */ /* TT_Process_Simple_Glyph */ /* */ /* <Description> */ /* Once a simple glyph has been loaded, it needs to be processed. */ /* Usually, this means scaling and hinting through bytecode */ /* interpretation. */ /* */ static FT_Error TT_Process_Simple_Glyph( TT_Loader load, FT_Bool debug ) { FT_GlyphLoader gloader = load->gloader; FT_Outline* outline = &gloader->current.outline; FT_UInt n_points = outline->n_points; #ifdef TT_CONFIG_OPTION_BYTECODE_INTERPRETER FT_UInt n_ins; #endif TT_GlyphZone zone = &load->zone; FT_Error error = TT_Err_Ok; FT_UNUSED( debug ); /* used by truetype interpreter only */ #ifdef TT_CONFIG_OPTION_BYTECODE_INTERPRETER n_ins = load->glyph->control_len; #endif /* add shadow points */ /* Now add the two shadow points at n and n + 1. */ /* We need the left side bearing and advance width. */ { FT_Vector* pp1; FT_Vector* pp2; /* pp1 = xMin - lsb */ pp1 = outline->points + 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; outline->tags[n_points ] = 0; outline->tags[n_points + 1] = 0; } /* Note that we return two more points that are not */ /* part of the glyph outline. */ n_points += 2; /* set up zone for hinting */ tt_prepare_zone( zone, &gloader->current, 0, 0 ); /* eventually scale the glyph */ if ( !( load->load_flags & FT_LOAD_NO_SCALE ) ) { FT_Vector* vec = zone->cur; FT_Vector* limit = vec + n_points; FT_Fixed x_scale = load->size->metrics.x_scale; FT_Fixed y_scale = load->size->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 ); } } cur_to_org( n_points, zone ); /* eventually hint the glyph */ if ( IS_HINTED( load->load_flags ) ) { FT_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 ) { error = TT_Set_CodeRange( load->exec, tt_coderange_glyph, load->exec->glyphIns, n_ins ); if ( error ) goto Exit; load->exec->is_composite = FALSE; load->exec->pedantic_hinting = (FT_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 ) goto Exit; error = TT_Err_Ok; /* ignore bytecode errors in non-pedantic mode */ } #endif /* TT_CONFIG_OPTION_BYTECODE_INTERPRETER */ } /* save glyph phantom points */ if ( !load->preserve_pps ) { load->pp1 = zone->cur[n_points - 2]; load->pp2 = zone->cur[n_points - 1]; } #ifdef TT_CONFIG_OPTION_BYTECODE_INTERPRETER Exit: #endif return error; } /*************************************************************************/ /* */ /* <Function> */ /* load_truetype_glyph */ /* */ /* <Description> */ /* Loads a given truetype glyph. Handles composites and uses a */ /* TT_Loader object. */ /* */ static FT_Error load_truetype_glyph( TT_Loader loader, FT_UInt glyph_index ) { #ifdef TT_CONFIG_OPTION_BYTECODE_INTERPRETER FT_Stream stream = loader->stream; #endif FT_Error error; TT_Face face = (TT_Face)loader->face; FT_ULong offset; FT_Int contours_count; FT_UInt num_points, count; FT_Fixed x_scale, y_scale; FT_GlyphLoader gloader = loader->gloader; FT_Bool opened_frame = 0; #ifdef FT_CONFIG_OPTION_INCREMENTAL struct FT_StreamRec_ inc_stream; FT_Data glyph_data; FT_Bool glyph_data_loaded = 0; #endif /* check glyph index */ if ( glyph_index >= (FT_UInt)face->root.num_glyphs ) { error = TT_Err_Invalid_Glyph_Index; goto Exit; } loader->glyph_index = glyph_index; num_points = 0; x_scale = 0x10000L; y_scale = 0x10000L; if ( ( loader->load_flags & FT_LOAD_NO_SCALE ) == 0 ) { x_scale = loader->size->metrics.x_scale; y_scale = loader->size->metrics.y_scale; } /* get horizontal metrics */ { FT_Short left_bearing = 0; FT_UShort advance_width = 0; #ifdef FT_CONFIG_OPTION_INCREMENTAL FT_Bool metrics_found = FALSE; /* If this is an incrementally loaded font see if there are */ /* overriding metrics for this glyph. */ if ( face->root.internal->incremental_interface && face->root.internal->incremental_interface->funcs->get_glyph_metrics ) { FT_Incremental_MetricsRec m; error = face->root.internal->incremental_interface->funcs->get_glyph_metrics( face->root.internal->incremental_interface->object, glyph_index, FALSE, &m, &metrics_found ); if ( error ) goto Exit; left_bearing = (FT_Short)m.bearing_x; advance_width = (FT_UShort)m.advance; } if ( !metrics_found ) Get_HMetrics( face, glyph_index, (FT_Bool)!( loader->load_flags & FT_LOAD_IGNORE_GLOBAL_ADVANCE_WIDTH ), &left_bearing, &advance_width ); #else Get_HMetrics( face, glyph_index, (FT_Bool)!( loader->load_flags & FT_LOAD_IGNORE_GLOBAL_ADVANCE_WIDTH ), &left_bearing, &advance_width ); #endif /* FT_CONFIG_OPTION_INCREMENTAL */ loader->left_bearing = left_bearing; loader->advance = advance_width; if ( !loader->linear_def ) { loader->linear_def = 1; loader->linear = advance_width; } } #ifdef FT_CONFIG_OPTION_INCREMENTAL /* Set `offset' to the start of the glyph program relative to the */ /* start of the 'glyf' table, and `count' to the length of the */ /* glyph program in bytes. */ /* */ /* If we are loading glyph data via the incremental interface, set */ /* the loader stream to a memory stream reading the data returned */ /* by the interface. */ if ( face->root.internal->incremental_interface ) { error = face->root.internal->incremental_interface->funcs->get_glyph_data( face->root.internal->incremental_interface->object, glyph_index, &glyph_data ); if ( error ) goto Exit; glyph_data_loaded = 1; offset = 0; count = glyph_data.length; FT_MEM_ZERO( &inc_stream, sizeof ( inc_stream ) ); FT_Stream_OpenMemory( &inc_stream, glyph_data.pointer, glyph_data.length ); loader->stream = &inc_stream; } else #endif /* FT_CONFIG_OPTION_INCREMENTAL */ { offset = face->glyph_locations[glyph_index]; count = 0; if ( glyph_index < (FT_UInt)face->num_locations - 1 ) count = face->glyph_locations[glyph_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 error = TT_Err_Ok; goto Exit; } loader->byte_len = (FT_Int)count; offset = loader->glyf_offset + offset; /* access glyph frame */ error = face->access_glyph_frame( loader, glyph_index, offset, count ); if ( error ) goto Exit; opened_frame = 1; /* read first glyph header */ error = face->read_glyph_header( loader ); if ( error ) goto Fail; contours_count = loader->n_contours; count -= 10; 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 ) { /* check that we can add the contours to the glyph */ error = FT_GlyphLoader_CheckPoints( gloader, 0, contours_count ); if ( error ) goto Fail; error = face->read_simple_glyph( loader ); if ( error ) goto Fail; #ifdef TT_CONFIG_OPTION_BYTECODE_INTERPRETER { TT_Size size = (TT_Size)loader->size; error = TT_Process_Simple_Glyph( loader, (FT_Bool)( size && size->debug ) ); } #else error = TT_Process_Simple_Glyph( loader, 0 ); #endif if ( error ) goto Fail; FT_GlyphLoader_Add( gloader ); /* Note: We could have put the simple loader source there */ /* but the code is fat enough already :-) */ } /***********************************************************************/ /***********************************************************************/ /***********************************************************************/ /* otherwise, load a composite! */ else { TT_GlyphSlot glyph = (TT_GlyphSlot)loader->glyph; FT_UInt start_point; #ifdef TT_CONFIG_OPTION_BYTECODE_INTERPRETER FT_UInt start_contour; FT_ULong ins_pos; /* position of composite instructions, if any */ #endif /* for each subglyph, read composite header */ start_point = gloader->base.outline.n_points; #ifdef TT_CONFIG_OPTION_BYTECODE_INTERPRETER start_contour = gloader->base.outline.n_contours; #endif error = face->read_composite_glyph( loader ); if ( error ) goto Fail; #ifdef TT_CONFIG_OPTION_BYTECODE_INTERPRETER ins_pos = loader->ins_pos; #endif face->forget_glyph_frame( loader ); opened_frame = 0; /* 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 these data)... */ /* */ if ( loader->load_flags & FT_LOAD_NO_RECURSE ) { /* set up remaining glyph fields */ FT_GlyphLoader_Add( gloader ); glyph->num_subglyphs = gloader->base.num_subglyphs; glyph->format = FT_GLYPH_FORMAT_COMPOSITE; glyph->subglyphs = gloader->base.subglyphs; goto Exit; } /*********************************************************************/ /*********************************************************************/ /*********************************************************************/ /* Now, read each subglyph independently. */ { FT_Int n, num_base_points, num_new_points; FT_SubGlyph subglyph = 0; FT_UInt num_subglyphs = gloader->current.num_subglyphs; FT_UInt num_base_subgs = gloader->base.num_subglyphs; FT_GlyphLoader_Add( gloader ); for ( n = 0; n < (FT_Int)num_subglyphs; n++ ) { FT_Vector pp1, pp2; FT_Pos x, y; /* Each time we call load_truetype_glyph in this loop, the */ /* value of `gloader.base.subglyphs' can change due to table */ /* reallocations. We thus need to recompute the subglyph */ /* pointer on each iteration. */ subglyph = gloader->base.subglyphs + num_base_subgs + n; pp1 = loader->pp1; pp2 = loader->pp2; num_base_points = gloader->base.outline.n_points; error = load_truetype_glyph( loader, subglyph->index ); if ( error ) goto Fail; /* restore subglyph pointer */ subglyph = gloader->base.subglyphs + num_base_subgs + n; if ( subglyph->flags & USE_MY_METRICS ) { pp1 = loader->pp1; pp2 = loader->pp2; } else { loader->pp1 = pp1; loader->pp2 = pp2; } num_points = gloader->base.outline.n_points; 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 ) ) { FT_Vector* cur = gloader->base.outline.points + num_base_points; FT_Vector* org = gloader->base.extra_points + num_base_points; FT_Vector* limit = cur + num_new_points; for ( ; cur < limit; cur++, org++ ) { FT_Vector_Transform( cur, &subglyph->transform ); FT_Vector_Transform( org, &subglyph->transform ); } } /* apply offset */ if ( !( subglyph->flags & ARGS_ARE_XY_VALUES ) ) { FT_UInt k = subglyph->arg1; FT_UInt l = subglyph->arg2; FT_Vector* p1; FT_Vector* p2; if ( start_point + k >= (FT_UInt)num_base_points || l >= (FT_UInt)num_new_points ) { error = TT_Err_Invalid_Composite; goto Fail; } l += num_base_points; p1 = gloader->base.outline.points + start_point + k; p2 = gloader->base.outline.points + start_point + l; x = p1->x - p2->x; y = p1->y - p2->y; } else { x = subglyph->arg1; y = subglyph->arg2; /* Use a default value dependent on */ /* TT_CONFIG_OPTION_COMPONENT_OFFSET_SCALED. This is useful for old TT */ /* fonts which don't set the xxx_COMPONENT_OFFSET bit. */ #ifdef TT_CONFIG_OPTION_COMPONENT_OFFSET_SCALED if ( !( subglyph->flags & UNSCALED_COMPONENT_OFFSET ) && #else if ( ( subglyph->flags & SCALED_COMPONENT_OFFSET ) && #endif ( subglyph->flags & ( WE_HAVE_A_SCALE | WE_HAVE_AN_XY_SCALE | WE_HAVE_A_2X2 )) ) { #if 0 /*************************************************************************/ /* */ /* This algorithm is what Apple documents. But it doesn't work. */ /* */ int a = subglyph->transform.xx > 0 ? subglyph->transform.xx : -subglyph->transform.xx; int b = subglyph->transform.yx > 0 ? subglyph->transform.yx : -subglyph->transform.yx; int c = subglyph->transform.xy > 0 ? subglyph->transform.xy : -subglyph->transform.xy; int d = subglyph->transform.yy > 0 ? subglyph->transform.yy : -subglyph->transform.yy; int m = a > b ? a : b; int n = c > d ? c : d; if ( a - b <= 33 && a - b >= -33 ) m *= 2; if ( c - d <= 33 && c - d >= -33 ) n *= 2; x = FT_MulFix( x, m ); y = FT_MulFix( y, n ); #else /* 0 */ /*************************************************************************/ /* */ /* This algorithm is a guess and works much better than the above. */ /* */ int mac_xscale = FT_SqrtFixed( FT_MulFix( subglyph->transform.xx, subglyph->transform.xx ) + FT_MulFix( subglyph->transform.xy, subglyph->transform.xy) ); int mac_yscale = FT_SqrtFixed( FT_MulFix( subglyph->transform.yy, subglyph->transform.yy ) + FT_MulFix( subglyph->transform.yx, subglyph->transform.yx ) ); x = FT_MulFix( x, mac_xscale ); y = FT_MulFix( y, mac_yscale ); #endif /* 0 */ } 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; } } } if ( x || y ) { translate_array( num_new_points, gloader->base.outline.points + num_base_points, x, y ); translate_array( num_new_points, gloader->base.extra_points + num_base_points, x, y ); } } /*******************************************************************/ /*******************************************************************/ /*******************************************************************/ /* we have finished loading all sub-glyphs; now, look for */ /* instructions for this composite! */ #ifdef TT_CONFIG_OPTION_BYTECODE_INTERPRETER if ( num_subglyphs > 0 && loader->exec && ins_pos > 0 && subglyph->flags & WE_HAVE_INSTR ) { FT_UShort n_ins; TT_ExecContext exec = loader->exec; TT_GlyphZone pts; FT_Vector* pp1; /* read size of instructions */ if ( FT_STREAM_SEEK( ins_pos ) || FT_READ_USHORT( n_ins ) ) goto Fail; FT_TRACE5(( " Instructions size = %d\n", n_ins )); /* in some fonts? */ if ( n_ins == 0xFFFFU ) n_ins = 0; /* check it */ if ( n_ins > face->max_profile.maxSizeOfInstructions ) { FT_TRACE0(( "Too many instructions (%d) in composite glyph %ld\n", n_ins, subglyph->index )); error = TT_Err_Too_Many_Hints; goto Fail; } /* read the instructions */ if ( FT_STREAM_READ( exec->glyphIns, n_ins ) ) goto Fail; glyph->control_data = exec->glyphIns; glyph->control_len = n_ins; error = TT_Set_CodeRange( exec, tt_coderange_glyph, exec->glyphIns, n_ins ); if ( error ) goto Fail; /* prepare the execution context */ tt_prepare_zone( &exec->pts, &gloader->base, start_point, start_contour ); pts = &exec->pts; pts->n_points = (short)(num_points + 2); pts->n_contours = gloader->base.outline.n_contours; /* add phantom points */ pp1 = pts->cur + num_points; pp1[0] = loader->pp1; pp1[1] = loader->pp2; pts->tags[num_points ] = 0; pts->tags[num_points + 1] = 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 ); } { FT_UInt k; for ( k = 0; k < num_points; k++ ) pts->tags[k] &= FT_CURVE_TAG_ON; } cur_to_org( num_points + 2, pts ); /* now consider hinting */ if ( IS_HINTED( loader->load_flags ) && n_ins > 0 ) { exec->is_composite = TRUE; exec->pedantic_hinting = (FT_Bool)( loader->load_flags & FT_LOAD_PEDANTIC ); error = TT_Run_Context( exec, ((TT_Size)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 /* TT_CONFIG_OPTION_BYTECODE_INTERPRETER */ } /* end of composite loading */ } /***********************************************************************/ /***********************************************************************/ /***********************************************************************/ Fail: if ( opened_frame ) face->forget_glyph_frame( loader ); Exit: #ifdef FT_CONFIG_OPTION_INCREMENTAL if ( glyph_data_loaded ) face->root.internal->incremental_interface->funcs->free_glyph_data( face->root.internal->incremental_interface->object, &glyph_data ); #endif return error; } static FT_Error compute_glyph_metrics( TT_Loader loader, FT_UInt glyph_index ) { FT_BBox bbox; TT_Face face = (TT_Face)loader->face; FT_Fixed y_scale; TT_GlyphSlot glyph = loader->glyph; TT_Size size = (TT_Size)loader->size; y_scale = 0x10000L; if ( ( loader->load_flags & FT_LOAD_NO_SCALE ) == 0 ) y_scale = size->root.metrics.y_scale; if ( glyph->format != FT_GLYPH_FORMAT_COMPOSITE ) { glyph->outline.flags &= ~FT_OUTLINE_SINGLE_PASS; /* copy outline to our glyph slot */ FT_GlyphLoader_CopyPoints( glyph->internal->loader, loader->gloader ); glyph->outline = glyph->internal->loader->base.outline; /* translate array so that (0,0) is the glyph's origin */ FT_Outline_Translate( &glyph->outline, -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 horizontal advance. It is scaled later */ /* by the base layer. */ { FT_Pos advance = loader->linear; /* the flag FT_LOAD_IGNORE_GLOBAL_ADVANCE_WIDTH was introduced to */ /* correctly support DynaLab fonts, which 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; /* we need to return the advance in font units in linearHoriAdvance, */ /* it will be scaled later by the base layer. */ glyph->linearHoriAdvance = advance; } glyph->metrics.horiBearingX = bbox.xMin; glyph->metrics.horiBearingY = bbox.yMax; glyph->metrics.horiAdvance = loader->pp2.x - loader->pp1.x; /* don't forget to hint the advance when we need to */ if ( IS_HINTED( loader->load_flags ) ) glyph->metrics.horiAdvance = ( glyph->metrics.horiAdvance + 32 ) & -64; /* 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'... */ { FT_Short top_bearing; /* vertical top side bearing (EM units) */ FT_UShort advance_height; /* vertical advance height (EM units) */ FT_Pos left; /* scaled vertical left side bearing */ FT_Pos top; /* scaled vertical top side bearing */ FT_Pos advance; /* scaled vertical advance height */ FT_Bool metrics_found = FALSE; #ifdef FT_CONFIG_OPTION_INCREMENTAL /* If this is an incrementally loaded font see if there are */ /* overriding metrics for this glyph. */ if ( face->root.internal->incremental_interface && face->root.internal->incremental_interface->funcs->get_glyph_metrics ) { FT_Incremental_MetricsRec m; FT_Error error = face->root.internal->incremental_interface->funcs->get_glyph_metrics( face->root.internal->incremental_interface->object, glyph_index, TRUE, &m, &metrics_found ); if ( error ) return error; top_bearing = (FT_Short)m.bearing_y; advance_height = (FT_UShort)m.advance; } #endif /* FT_CONFIG_OPTION_INCREMENTAL */ /* Get the unscaled top bearing and advance height. */ if ( !metrics_found && 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, if 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 != 0xFFFFU ) { top_bearing = (FT_Short)( face->os2.sTypoLineGap / 2 ); advance_height = (FT_UShort)( face->os2.sTypoAscender - face->os2.sTypoDescender + face->os2.sTypoLineGap ); } else { top_bearing = (FT_Short)( face->horizontal.Line_Gap / 2 ); advance_height = (FT_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 */ /* FT_Get_Outline_CBox(). */ /* scale the metrics */ if ( !( loader->load_flags & FT_LOAD_NO_SCALE ) ) { top = FT_MulFix( top_bearing + loader->bbox.yMax, y_scale ) - bbox.yMax; advance = FT_MulFix( advance_height, y_scale ); } else { top = top_bearing + loader->bbox.yMax - bbox.yMax; advance = advance_height; } /* set the advance height in design units. It is scaled later by */ /* the base layer. */ glyph->linearVertAdvance = advance_height; /* 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 ) ) { FT_Byte* widths = Get_Advance_Widths( face, size->root.metrics.x_ppem ); if ( widths ) glyph->metrics.horiAdvance = widths[glyph_index] << 6; } /* set glyph dimensions */ glyph->metrics.width = bbox.xMax - bbox.xMin; glyph->metrics.height = bbox.yMax - bbox.yMin; return 0; } /*************************************************************************/ /* */ /* <Function> */ /* TT_Load_Glyph */ /* */ /* <Description> */ /* A function used to load a single glyph within a given glyph slot, */ /* for a given size. */ /* */ /* <Input> */ /* glyph :: A handle to a target slot object where the glyph */ /* will be loaded. */ /* */ /* size :: A handle to the source face size at which the glyph */ /* must be scaled/loaded. */ /* */ /* glyph_index :: The index of the glyph in the font file. */ /* */ /* load_flags :: A flag indicating what to load for this glyph. The */ /* FT_LOAD_XXX constants can be used to control the */ /* glyph loading process (e.g., whether the outline */ /* should be scaled, whether to load bitmaps or not, */ /* whether to hint the outline, etc). */ /* */ /* <Return> */ /* FreeType error code. 0 means success. */ /* */ FT_LOCAL_DEF( FT_Error ) TT_Load_Glyph( TT_Size size, TT_GlyphSlot glyph, FT_UShort glyph_index, FT_Int32 load_flags ) { SFNT_Service sfnt; TT_Face face; FT_Stream stream; FT_Error error; TT_LoaderRec loader; face = (TT_Face)glyph->face; sfnt = (SFNT_Service)face->sfnt; stream = face->root.stream; 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 */ /* */ /* XXX: The convention should be emphasized in */ /* the documents because it can be confusing. */ if ( size && size->strike_index != 0xFFFFU && sfnt->load_sbits && ( load_flags & FT_LOAD_NO_BITMAP ) == 0 ) { TT_SBit_MetricsRec metrics; error = sfnt->load_sbit_image( face, size->strike_index, glyph_index, load_flags, stream, &glyph->bitmap, &metrics ); if ( !error ) { glyph->outline.n_points = 0; glyph->outline.n_contours = 0; glyph->metrics.width = (FT_Pos)metrics.width << 6; glyph->metrics.height = (FT_Pos)metrics.height << 6; glyph->metrics.horiBearingX = (FT_Pos)metrics.horiBearingX << 6; glyph->metrics.horiBearingY = (FT_Pos)metrics.horiBearingY << 6; glyph->metrics.horiAdvance = (FT_Pos)metrics.horiAdvance << 6; glyph->metrics.vertBearingX = (FT_Pos)metrics.vertBearingX << 6; glyph->metrics.vertBearingY = (FT_Pos)metrics.vertBearingY << 6; glyph->metrics.vertAdvance = (FT_Pos)metrics.vertAdvance << 6; glyph->format = FT_GLYPH_FORMAT_BITMAP; if ( load_flags & FT_LOAD_VERTICAL_LAYOUT ) { glyph->bitmap_left = metrics.vertBearingX; glyph->bitmap_top = metrics.vertBearingY; } else { glyph->bitmap_left = metrics.horiBearingX; glyph->bitmap_top = metrics.horiBearingY; } return error; } } #endif /* TT_CONFIG_OPTION_EMBEDDED_BITMAPS */ /* return immediately if we only want the embedded bitmaps */ if ( load_flags & FT_LOAD_SBITS_ONLY ) return FT_Err_Invalid_Argument; /* seek to the beginning of the glyph table. For Type 42 fonts */ /* the table might be accessed from a Postscript stream or something */ /* else... */ #ifdef FT_CONFIG_OPTION_INCREMENTAL /* Don't look for the glyph table if this is an incremental font. */ if ( !face->root.internal->incremental_interface ) #endif { error = face->goto_table( face, TTAG_glyf, stream, 0 ); if ( error ) { FT_ERROR(( "TT_Load_Glyph: could not access glyph table\n" )); goto Exit; } } FT_MEM_ZERO( &loader, sizeof ( loader ) ); /* update the glyph zone bounds */ { FT_GlyphLoader gloader = FT_FACE_DRIVER(face)->glyph_loader; loader.gloader = gloader; FT_GlyphLoader_Rewind( gloader ); tt_prepare_zone( &loader.zone, &gloader->base, 0, 0 ); tt_prepare_zone( &loader.base, &gloader->base, 0, 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 ); loader.instructions = loader.exec->glyphIns; /* 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 = 0; /* let's initialize the rest of our loader now */ loader.load_flags = load_flags; loader.face = (FT_Face)face; loader.size = (FT_Size)size; loader.glyph = (FT_GlyphSlot)glyph; loader.stream = stream; #ifdef FT_CONFIG_OPTION_INCREMENTAL if ( face->root.internal->incremental_interface ) loader.glyf_offset = 0; else #endif loader.glyf_offset = FT_STREAM_POS(); #ifdef TT_CONFIG_OPTION_BYTECODE_INTERPRETER /* if 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 /* TT_CONFIG_OPTION_BYTECODE_INTERPRETER */ /* Main loading loop */ glyph->format = FT_GLYPH_FORMAT_OUTLINE; glyph->num_subglyphs = 0; 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 /* TT_CONFIG_OPTION_BYTECODE_INTERPRETER */ /* Set the `high precision' bit flag. */ /* This is _critical_ to get correct output for monochrome */ /* TrueType glyphs at all sizes using the bytecode interpreter. */ /* */ if ( size && size->root.metrics.y_ppem < 24 ) glyph->outline.flags |= FT_OUTLINE_HIGH_PRECISION; Exit: return error; } /* END */