diff options
Diffstat (limited to 'src/freetype/cffdecode.c')
| -rw-r--r-- | src/freetype/cffdecode.c | 239 |
1 files changed, 239 insertions, 0 deletions
diff --git a/src/freetype/cffdecode.c b/src/freetype/cffdecode.c new file mode 100644 index 0000000..0e62935 --- /dev/null +++ b/src/freetype/cffdecode.c @@ -0,0 +1,239 @@ +/***************************************************************************/ +/* */ +/* cffdecode.c */ +/* */ +/* PostScript CFF (Type 2) decoding routines (body). */ +/* */ +/* Copyright 2017-2018 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_FREETYPE_H +#include FT_INTERNAL_DEBUG_H +#include FT_INTERNAL_SERVICE_H +#include FT_SERVICE_CFF_TABLE_LOAD_H + +#include "cffdecode.h" +#include "psobjs.h" + +#include "psauxerr.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_cffdecode + + + /*************************************************************************/ + /*************************************************************************/ + /*************************************************************************/ + /********** *********/ + /********** *********/ + /********** GENERIC CHARSTRING PARSING *********/ + /********** *********/ + /********** *********/ + /*************************************************************************/ + /*************************************************************************/ + /*************************************************************************/ + + /*************************************************************************/ + /* */ + /* <Function> */ + /* cff_compute_bias */ + /* */ + /* <Description> */ + /* Computes the bias value in dependence of the number of glyph */ + /* subroutines. */ + /* */ + /* <Input> */ + /* in_charstring_type :: The `CharstringType' value of the top DICT */ + /* dictionary. */ + /* */ + /* num_subrs :: The number of glyph subroutines. */ + /* */ + /* <Return> */ + /* The bias value. */ + static FT_Int + cff_compute_bias( FT_Int in_charstring_type, + FT_UInt num_subrs ) + { + FT_Int result; + + + if ( in_charstring_type == 1 ) + result = 0; + else if ( num_subrs < 1240 ) + result = 107; + else if ( num_subrs < 33900U ) + result = 1131; + else + result = 32768U; + + return result; + } + + + FT_LOCAL_DEF( FT_Int ) + cff_lookup_glyph_by_stdcharcode( CFF_Font cff, + FT_Int charcode ) + { + FT_UInt n; + FT_UShort glyph_sid; + + FT_Service_CFFLoad cffload; + + + /* CID-keyed fonts don't have glyph names */ + if ( !cff->charset.sids ) + return -1; + + /* check range of standard char code */ + if ( charcode < 0 || charcode > 255 ) + return -1; + + cffload = (FT_Service_CFFLoad)cff->cffload; + + /* Get code to SID mapping from `cff_standard_encoding'. */ + glyph_sid = cffload->get_standard_encoding( (FT_UInt)charcode ); + + for ( n = 0; n < cff->num_glyphs; n++ ) + { + if ( cff->charset.sids[n] == glyph_sid ) + return (FT_Int)n; + } + + return -1; + } + + + /*************************************************************************/ + /* */ + /* <Function> */ + /* cff_decoder_init */ + /* */ + /* <Description> */ + /* Initializes a given glyph decoder. */ + /* */ + /* <InOut> */ + /* decoder :: A pointer to the glyph builder to initialize. */ + /* */ + /* <Input> */ + /* face :: The current face object. */ + /* */ + /* size :: The current size object. */ + /* */ + /* slot :: The current glyph object. */ + /* */ + /* hinting :: Whether hinting is active. */ + /* */ + /* hint_mode :: The hinting mode. */ + /* */ + FT_LOCAL_DEF( void ) + cff_decoder_init( CFF_Decoder* decoder, + TT_Face face, + CFF_Size size, + CFF_GlyphSlot slot, + FT_Bool hinting, + FT_Render_Mode hint_mode, + CFF_Decoder_Get_Glyph_Callback get_callback, + CFF_Decoder_Free_Glyph_Callback free_callback ) + { + CFF_Font cff = (CFF_Font)face->extra.data; + + + /* clear everything */ + FT_ZERO( decoder ); + + /* initialize builder */ + cff_builder_init( &decoder->builder, face, size, slot, hinting ); + + /* initialize Type2 decoder */ + decoder->cff = cff; + decoder->num_globals = cff->global_subrs_index.count; + decoder->globals = cff->global_subrs; + decoder->globals_bias = cff_compute_bias( + cff->top_font.font_dict.charstring_type, + decoder->num_globals ); + + decoder->hint_mode = hint_mode; + + decoder->get_glyph_callback = get_callback; + decoder->free_glyph_callback = free_callback; + } + + + /* this function is used to select the subfont */ + /* and the locals subrs array */ + FT_LOCAL_DEF( FT_Error ) + cff_decoder_prepare( CFF_Decoder* decoder, + CFF_Size size, + FT_UInt glyph_index ) + { + CFF_Builder *builder = &decoder->builder; + CFF_Font cff = (CFF_Font)builder->face->extra.data; + CFF_SubFont sub = &cff->top_font; + FT_Error error = FT_Err_Ok; + + FT_Service_CFFLoad cffload = (FT_Service_CFFLoad)cff->cffload; + + + /* manage CID fonts */ + if ( cff->num_subfonts ) + { + FT_Byte fd_index = cffload->fd_select_get( &cff->fd_select, + glyph_index ); + + + if ( fd_index >= cff->num_subfonts ) + { + FT_TRACE4(( "cff_decoder_prepare: invalid CID subfont index\n" )); + error = FT_THROW( Invalid_File_Format ); + goto Exit; + } + + FT_TRACE3(( " in subfont %d:\n", fd_index )); + + sub = cff->subfonts[fd_index]; + + if ( builder->hints_funcs && size ) + { + FT_Size ftsize = FT_SIZE( size ); + CFF_Internal internal = (CFF_Internal)ftsize->internal->module_data; + + + /* for CFFs without subfonts, this value has already been set */ + builder->hints_globals = (void *)internal->subfonts[fd_index]; + } + } + + decoder->num_locals = sub->local_subrs_index.count; + decoder->locals = sub->local_subrs; + decoder->locals_bias = cff_compute_bias( + decoder->cff->top_font.font_dict.charstring_type, + decoder->num_locals ); + + decoder->glyph_width = sub->private_dict.default_width; + decoder->nominal_width = sub->private_dict.nominal_width; + + decoder->current_subfont = sub; + + Exit: + return error; + } + + +/* END */ |