const char* af_shaper_get_cluster( const char* p, AF_StyleMetrics metrics, void* buf_, unsigned int* count ) { FT_Face face = metrics->globals->face; FT_ULong ch, dummy = 0; FT_ULong* buf = (FT_ULong*)buf_; while ( *p == ' ' ) p++; GET_UTF8_CHAR( ch, p ); /* since we don't have an engine to handle clusters, */ /* we scan the characters but return zero */ while ( !( *p == ' ' || *p == '\0' ) ) GET_UTF8_CHAR( dummy, p ); if ( dummy ) { *buf = 0; *count = 0; } else { *buf = FT_Get_Char_Index( face, ch ); *count = 1; } return p; }
int utf8Comp(char *ptr, char *ptr2) { while(*ptr && *ptr2) { unsigned short c, c2; GET_UTF8_CHAR(ptr, c); GET_UTF8_CHAR(ptr2, c2); if(c != c2) return FALSE; } if(*ptr || *ptr2) return FALSE; return TRUE; }
int utf8Hash(char *utf8) { int hash = 0; while(*utf8) { unsigned short c; GET_UTF8_CHAR(utf8, c); hash = hash * 37 + c; } return hash; }
void convertUtf8(char *utf8, unsigned short *buff) { while(*utf8) GET_UTF8_CHAR(utf8, *buff++); }
FT_Error af_get_coverage( AF_FaceGlobals globals, AF_StyleClass style_class, FT_UShort* gstyles ) { hb_face_t* face; hb_set_t* gsub_lookups; /* GSUB lookups for a given script */ hb_set_t* gsub_glyphs; /* glyphs covered by GSUB lookups */ hb_set_t* gpos_lookups; /* GPOS lookups for a given script */ hb_set_t* gpos_glyphs; /* glyphs covered by GPOS lookups */ hb_script_t script; const hb_tag_t* coverage_tags; hb_tag_t script_tags[] = { HB_TAG_NONE, HB_TAG_NONE, HB_TAG_NONE, HB_TAG_NONE }; hb_codepoint_t idx; #ifdef FT_DEBUG_LEVEL_TRACE int count; #endif if ( !globals || !style_class || !gstyles ) return FT_THROW( Invalid_Argument ); face = hb_font_get_face( globals->hb_font ); gsub_lookups = hb_set_create(); gsub_glyphs = hb_set_create(); gpos_lookups = hb_set_create(); gpos_glyphs = hb_set_create(); coverage_tags = coverages[style_class->coverage]; script = scripts[style_class->script]; /* Convert a HarfBuzz script tag into the corresponding OpenType */ /* tag or tags -- some Indic scripts like Devanagari have an old */ /* and a new set of features. */ hb_ot_tags_from_script( script, &script_tags[0], &script_tags[1] ); /* `hb_ot_tags_from_script' usually returns HB_OT_TAG_DEFAULT_SCRIPT */ /* as the second tag. We change that to HB_TAG_NONE except for the */ /* default script. */ if ( style_class->script == globals->module->default_script && style_class->coverage == AF_COVERAGE_DEFAULT ) { if ( script_tags[0] == HB_TAG_NONE ) script_tags[0] = HB_OT_TAG_DEFAULT_SCRIPT; else { if ( script_tags[1] == HB_TAG_NONE ) script_tags[1] = HB_OT_TAG_DEFAULT_SCRIPT; else if ( script_tags[1] != HB_OT_TAG_DEFAULT_SCRIPT ) script_tags[2] = HB_OT_TAG_DEFAULT_SCRIPT; } } else { if ( script_tags[1] == HB_OT_TAG_DEFAULT_SCRIPT ) script_tags[1] = HB_TAG_NONE; } hb_ot_layout_collect_lookups( face, HB_OT_TAG_GSUB, script_tags, NULL, coverage_tags, gsub_lookups ); if ( hb_set_is_empty( gsub_lookups ) ) goto Exit; /* nothing to do */ hb_ot_layout_collect_lookups( face, HB_OT_TAG_GPOS, script_tags, NULL, coverage_tags, gpos_lookups ); FT_TRACE4(( "GSUB lookups (style `%s'):\n" " ", af_style_names[style_class->style] )); #ifdef FT_DEBUG_LEVEL_TRACE count = 0; #endif for ( idx = HB_SET_VALUE_INVALID; hb_set_next( gsub_lookups, &idx ); ) { #ifdef FT_DEBUG_LEVEL_TRACE FT_TRACE4(( " %d", idx )); count++; #endif /* get output coverage of GSUB feature */ hb_ot_layout_lookup_collect_glyphs( face, HB_OT_TAG_GSUB, idx, NULL, NULL, NULL, gsub_glyphs ); } #ifdef FT_DEBUG_LEVEL_TRACE if ( !count ) FT_TRACE4(( " (none)" )); FT_TRACE4(( "\n\n" )); #endif FT_TRACE4(( "GPOS lookups (style `%s'):\n" " ", af_style_names[style_class->style] )); #ifdef FT_DEBUG_LEVEL_TRACE count = 0; #endif for ( idx = HB_SET_VALUE_INVALID; hb_set_next( gpos_lookups, &idx ); ) { #ifdef FT_DEBUG_LEVEL_TRACE FT_TRACE4(( " %d", idx )); count++; #endif /* get input coverage of GPOS feature */ hb_ot_layout_lookup_collect_glyphs( face, HB_OT_TAG_GPOS, idx, NULL, gpos_glyphs, NULL, NULL ); } #ifdef FT_DEBUG_LEVEL_TRACE if ( !count ) FT_TRACE4(( " (none)" )); FT_TRACE4(( "\n\n" )); #endif /* * We now check whether we can construct blue zones, using glyphs * covered by the feature only. In case there is not a single zone * (this is, not a single character is covered), we skip this coverage. * */ if ( style_class->coverage != AF_COVERAGE_DEFAULT ) { AF_Blue_Stringset bss = style_class->blue_stringset; const AF_Blue_StringRec* bs = &af_blue_stringsets[bss]; FT_Bool found = 0; for ( ; bs->string != AF_BLUE_STRING_MAX; bs++ ) { const char* p = &af_blue_strings[bs->string]; while ( *p ) { hb_codepoint_t ch; GET_UTF8_CHAR( ch, p ); for ( idx = HB_SET_VALUE_INVALID; hb_set_next( gsub_lookups, &idx ); ) { hb_codepoint_t gidx = FT_Get_Char_Index( globals->face, ch ); if ( hb_ot_layout_lookup_would_substitute( face, idx, &gidx, 1, 1 ) ) { found = 1; break; } } } } if ( !found ) { FT_TRACE4(( " no blue characters found; style skipped\n" )); goto Exit; } } /* * Various OpenType features might use the same glyphs at different * vertical positions; for example, superscript and subscript glyphs * could be the same. However, the auto-hinter is completely * agnostic of OpenType features after the feature analysis has been * completed: The engine then simply receives a glyph index and returns a * hinted and usually rendered glyph. * * Consider the superscript feature of font `pala.ttf': Some of the * glyphs are `real', this is, they have a zero vertical offset, but * most of them are small caps glyphs shifted up to the superscript * position (this is, the `sups' feature is present in both the GSUB and * GPOS tables). The code for blue zones computation actually uses a * feature's y offset so that the `real' glyphs get correct hints. But * later on it is impossible to decide whether a glyph index belongs to, * say, the small caps or superscript feature. * * For this reason, we don't assign a style to a glyph if the current * feature covers the glyph in both the GSUB and the GPOS tables. This * is quite a broad condition, assuming that * * (a) glyphs that get used in multiple features are present in a * feature without vertical shift, * * and * * (b) a feature's GPOS data really moves the glyph vertically. * * Not fulfilling condition (a) makes a font larger; it would also * reduce the number of glyphs that could be addressed directly without * using OpenType features, so this assumption is rather strong. * * Condition (b) is much weaker, and there might be glyphs which get * missed. However, the OpenType features we are going to handle are * primarily located in GSUB, and HarfBuzz doesn't provide an API to * directly get the necessary information from the GPOS table. A * possible solution might be to directly parse the GPOS table to find * out whether a glyph gets shifted vertically, but this is something I * would like to avoid if not really necessary. * * Note that we don't follow this logic for the default coverage. * Complex scripts like Devanagari have mandatory GPOS features to * position many glyph elements, using mark-to-base or mark-to-ligature * tables; the number of glyphs missed due to condition (b) would be far * too large. * */ if ( style_class->coverage != AF_COVERAGE_DEFAULT ) hb_set_subtract( gsub_glyphs, gpos_glyphs ); #ifdef FT_DEBUG_LEVEL_TRACE FT_TRACE4(( " glyphs without GPOS data (`*' means already assigned)" )); count = 0; #endif for ( idx = HB_SET_VALUE_INVALID; hb_set_next( gsub_glyphs, &idx ); ) { #ifdef FT_DEBUG_LEVEL_TRACE if ( !( count % 10 ) ) FT_TRACE4(( "\n" " " )); FT_TRACE4(( " %d", idx )); count++; #endif /* glyph indices returned by `hb_ot_layout_lookup_collect_glyphs' */ /* can be arbitrary: some fonts use fake indices for processing */ /* internal to GSUB or GPOS, which is fully valid */ if ( idx >= (hb_codepoint_t)globals->glyph_count ) continue; if ( gstyles[idx] == AF_STYLE_UNASSIGNED ) gstyles[idx] = (FT_UShort)style_class->style; #ifdef FT_DEBUG_LEVEL_TRACE else FT_TRACE4(( "*" )); #endif } #ifdef FT_DEBUG_LEVEL_TRACE if ( !count ) FT_TRACE4(( "\n" " (none)" )); FT_TRACE4(( "\n\n" )); #endif Exit: hb_set_destroy( gsub_lookups ); hb_set_destroy( gsub_glyphs ); hb_set_destroy( gpos_lookups ); hb_set_destroy( gpos_glyphs ); return FT_Err_Ok; }
const char* af_shaper_get_cluster( const char* p, AF_StyleMetrics metrics, void* buf_, unsigned int* count ) { AF_StyleClass style_class; const hb_feature_t* feature; FT_Int upem; const char* q; int len; hb_buffer_t* buf = (hb_buffer_t*)buf_; hb_font_t* font; hb_codepoint_t dummy; upem = (FT_Int)metrics->globals->face->units_per_EM; style_class = metrics->style_class; feature = features[style_class->coverage]; font = metrics->globals->hb_font; /* we shape at a size of units per EM; this means font units */ hb_font_set_scale( font, upem, upem ); while ( *p == ' ' ) p++; /* count bytes up to next space (or end of buffer) */ q = p; while ( !( *q == ' ' || *q == '\0' ) ) GET_UTF8_CHAR( dummy, q ); len = (int)( q - p ); /* feed character(s) to the HarfBuzz buffer */ hb_buffer_clear_contents( buf ); hb_buffer_add_utf8( buf, p, len, 0, len ); /* we let HarfBuzz guess the script and writing direction */ hb_buffer_guess_segment_properties( buf ); /* shape buffer, which means conversion from character codes to */ /* glyph indices, possibly applying a feature */ hb_shape( font, buf, feature, feature ? 1 : 0 ); if ( feature ) { hb_buffer_t* hb_buf = metrics->globals->hb_buf; unsigned int gcount; hb_glyph_info_t* ginfo; unsigned int hb_gcount; hb_glyph_info_t* hb_ginfo; /* we have to check whether applying a feature does actually change */ /* glyph indices; otherwise the affected glyph or glyphs aren't */ /* available at all in the feature */ hb_buffer_clear_contents( hb_buf ); hb_buffer_add_utf8( hb_buf, p, len, 0, len ); hb_buffer_guess_segment_properties( hb_buf ); hb_shape( font, hb_buf, NULL, 0 ); ginfo = hb_buffer_get_glyph_infos( buf, &gcount ); hb_ginfo = hb_buffer_get_glyph_infos( hb_buf, &hb_gcount ); if ( gcount == hb_gcount ) { unsigned int i; for (i = 0; i < gcount; i++ ) if ( ginfo[i].codepoint != hb_ginfo[i].codepoint ) break; if ( i == gcount ) { /* both buffers have identical glyph indices */ hb_buffer_clear_contents( buf ); } } } *count = hb_buffer_get_length( buf ); #ifdef FT_DEBUG_LEVEL_TRACE if ( feature && *count > 1 ) FT_TRACE1(( "af_shaper_get_cluster:" " input character mapped to multiple glyphs\n" )); #endif return q; }