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Diffstat (limited to 'src/otlayout/ftxgsub.h')
| -rw-r--r-- | src/otlayout/ftxgsub.h | 613 |
1 files changed, 613 insertions, 0 deletions
diff --git a/src/otlayout/ftxgsub.h b/src/otlayout/ftxgsub.h new file mode 100644 index 000000000..8951e4413 --- /dev/null +++ b/src/otlayout/ftxgsub.h @@ -0,0 +1,613 @@ +/******************************************************************* + * + * ftxgsub.h + * + * TrueType Open GSUB table support + * + * Copyright 1996-2000 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. + * + ******************************************************************/ + +#ifndef FTXOPEN_H +#error "Don't include this file! Use ftxopen.h instead." +#endif + +#ifndef FTXGSUB_H +#define FTXGSUB_H + +#ifdef __cplusplus +extern "C" { +#endif + +#define TTO_Err_Invalid_GSUB_SubTable_Format 0x1010 +#define TTO_Err_Invalid_GSUB_SubTable 0x1011 + + +/* Lookup types for glyph substitution */ + +#define GSUB_LOOKUP_SINGLE 1 +#define GSUB_LOOKUP_MULTIPLE 2 +#define GSUB_LOOKUP_ALTERNATE 3 +#define GSUB_LOOKUP_LIGATURE 4 +#define GSUB_LOOKUP_CONTEXT 5 +#define GSUB_LOOKUP_CHAIN 6 +#define GSUB_LOOKUP_EXTENSION 7 + + +/* Use this if a feature applies to all glyphs */ + +#define ALL_GLYPHS 0xFFFF + + + /* A pointer to a function which selects the alternate glyph. `pos' is + the position of the glyph with index `glyphID', `num_alternates' + gives the number of alternates in the `alternates' array. `data' + points to the user-defined structure specified during a call to + TT_GSUB_Register_Alternate_Function(). The function must return an + index into the `alternates' array. */ + + typedef FT_UShort (*TTO_AltFunction)(FT_ULong pos, + FT_UShort glyphID, + FT_UShort num_alternates, + FT_UShort* alternates, + void* data ); + + + struct TTO_GSUBHeader_ + { + FT_Memory memory; + + FT_ULong offset; + + FT_Fixed Version; + + TTO_ScriptList ScriptList; + TTO_FeatureList FeatureList; + TTO_LookupList LookupList; + + TTO_GDEFHeader* gdef; + + /* the next two fields are used for an alternate substitution callback + function to select the proper alternate glyph. */ + + TTO_AltFunction altfunc; + void* data; + }; + + typedef struct TTO_GSUBHeader_ TTO_GSUBHeader; + typedef struct TTO_GSUBHeader_* TTO_GSUB; + + + /* LookupType 1 */ + + struct TTO_SingleSubstFormat1_ + { + FT_Short DeltaGlyphID; /* constant added to get + substitution glyph index */ + }; + + typedef struct TTO_SingleSubstFormat1_ TTO_SingleSubstFormat1; + + + struct TTO_SingleSubstFormat2_ + { + FT_UShort GlyphCount; /* number of glyph IDs in + Substitute array */ + FT_UShort* Substitute; /* array of substitute glyph IDs */ + }; + + typedef struct TTO_SingleSubstFormat2_ TTO_SingleSubstFormat2; + + + struct TTO_SingleSubst_ + { + FT_UShort SubstFormat; /* 1 or 2 */ + TTO_Coverage Coverage; /* Coverage table */ + + union + { + TTO_SingleSubstFormat1 ssf1; + TTO_SingleSubstFormat2 ssf2; + } ssf; + }; + + typedef struct TTO_SingleSubst_ TTO_SingleSubst; + + + /* LookupType 2 */ + + struct TTO_Sequence_ + { + FT_UShort GlyphCount; /* number of glyph IDs in the + Substitute array */ + FT_UShort* Substitute; /* string of glyph IDs to + substitute */ + }; + + typedef struct TTO_Sequence_ TTO_Sequence; + + + struct TTO_MultipleSubst_ + { + FT_UShort SubstFormat; /* always 1 */ + TTO_Coverage Coverage; /* Coverage table */ + FT_UShort SequenceCount; /* number of Sequence tables */ + TTO_Sequence* Sequence; /* array of Sequence tables */ + }; + + typedef struct TTO_MultipleSubst_ TTO_MultipleSubst; + + + /* LookupType 3 */ + + struct TTO_AlternateSet_ + { + FT_UShort GlyphCount; /* number of glyph IDs in the + Alternate array */ + FT_UShort* Alternate; /* array of alternate glyph IDs */ + }; + + typedef struct TTO_AlternateSet_ TTO_AlternateSet; + + + struct TTO_AlternateSubst_ + { + FT_UShort SubstFormat; /* always 1 */ + TTO_Coverage Coverage; /* Coverage table */ + FT_UShort AlternateSetCount; + /* number of AlternateSet tables */ + TTO_AlternateSet* AlternateSet; /* array of AlternateSet tables */ + }; + + typedef struct TTO_AlternateSubst_ TTO_AlternateSubst; + + + /* LookupType 4 */ + + struct TTO_Ligature_ + { + FT_UShort LigGlyph; /* glyphID of ligature + to substitute */ + FT_UShort ComponentCount; /* number of components in ligature */ + FT_UShort* Component; /* array of component glyph IDs */ + }; + + typedef struct TTO_Ligature_ TTO_Ligature; + + + struct TTO_LigatureSet_ + { + FT_UShort LigatureCount; /* number of Ligature tables */ + TTO_Ligature* Ligature; /* array of Ligature tables */ + }; + + typedef struct TTO_LigatureSet_ TTO_LigatureSet; + + + struct TTO_LigatureSubst_ + { + FT_UShort SubstFormat; /* always 1 */ + TTO_Coverage Coverage; /* Coverage table */ + FT_UShort LigatureSetCount; /* number of LigatureSet tables */ + TTO_LigatureSet* LigatureSet; /* array of LigatureSet tables */ + }; + + typedef struct TTO_LigatureSubst_ TTO_LigatureSubst; + + + /* needed by both lookup type 5 and 6 */ + + struct TTO_SubstLookupRecord_ + { + FT_UShort SequenceIndex; /* index into current + glyph sequence */ + FT_UShort LookupListIndex; /* Lookup to apply to that pos. */ + }; + + typedef struct TTO_SubstLookupRecord_ TTO_SubstLookupRecord; + + + /* LookupType 5 */ + + struct TTO_SubRule_ + { + FT_UShort GlyphCount; /* total number of input glyphs */ + FT_UShort SubstCount; /* number of SubstLookupRecord + tables */ + FT_UShort* Input; /* array of input glyph IDs */ + TTO_SubstLookupRecord* SubstLookupRecord; + /* array of SubstLookupRecord + tables */ + }; + + typedef struct TTO_SubRule_ TTO_SubRule; + + + struct TTO_SubRuleSet_ + { + FT_UShort SubRuleCount; /* number of SubRule tables */ + TTO_SubRule* SubRule; /* array of SubRule tables */ + }; + + typedef struct TTO_SubRuleSet_ TTO_SubRuleSet; + + + struct TTO_ContextSubstFormat1_ + { + TTO_Coverage Coverage; /* Coverage table */ + FT_UShort SubRuleSetCount; /* number of SubRuleSet tables */ + TTO_SubRuleSet* SubRuleSet; /* array of SubRuleSet tables */ + }; + + typedef struct TTO_ContextSubstFormat1_ TTO_ContextSubstFormat1; + + + struct TTO_SubClassRule_ + { + FT_UShort GlyphCount; /* total number of context classes */ + FT_UShort SubstCount; /* number of SubstLookupRecord + tables */ + FT_UShort* Class; /* array of classes */ + TTO_SubstLookupRecord* SubstLookupRecord; + /* array of SubstLookupRecord + tables */ + }; + + typedef struct TTO_SubClassRule_ TTO_SubClassRule; + + + struct TTO_SubClassSet_ + { + FT_UShort SubClassRuleCount; + /* number of SubClassRule tables */ + TTO_SubClassRule* SubClassRule; /* array of SubClassRule tables */ + }; + + typedef struct TTO_SubClassSet_ TTO_SubClassSet; + + + /* The `MaxContextLength' field is not defined in the TTO specification + but simplifies the implementation of this format. It holds the + maximal context length used in the context rules. */ + + struct TTO_ContextSubstFormat2_ + { + FT_UShort MaxContextLength; + /* maximal context length */ + TTO_Coverage Coverage; /* Coverage table */ + TTO_ClassDefinition ClassDef; /* ClassDef table */ + FT_UShort SubClassSetCount; + /* number of SubClassSet tables */ + TTO_SubClassSet* SubClassSet; /* array of SubClassSet tables */ + }; + + typedef struct TTO_ContextSubstFormat2_ TTO_ContextSubstFormat2; + + + struct TTO_ContextSubstFormat3_ + { + FT_UShort GlyphCount; /* number of input glyphs */ + FT_UShort SubstCount; /* number of SubstLookupRecords */ + TTO_Coverage* Coverage; /* array of Coverage tables */ + TTO_SubstLookupRecord* SubstLookupRecord; + /* array of substitution lookups */ + }; + + typedef struct TTO_ContextSubstFormat3_ TTO_ContextSubstFormat3; + + + struct TTO_ContextSubst_ + { + FT_UShort SubstFormat; /* 1, 2, or 3 */ + + union + { + TTO_ContextSubstFormat1 csf1; + TTO_ContextSubstFormat2 csf2; + TTO_ContextSubstFormat3 csf3; + } csf; + }; + + typedef struct TTO_ContextSubst_ TTO_ContextSubst; + + + /* LookupType 6 */ + + struct TTO_ChainSubRule_ + { + FT_UShort BacktrackGlyphCount; + /* total number of backtrack glyphs */ + FT_UShort* Backtrack; /* array of backtrack glyph IDs */ + FT_UShort InputGlyphCount; + /* total number of input glyphs */ + FT_UShort* Input; /* array of input glyph IDs */ + FT_UShort LookaheadGlyphCount; + /* total number of lookahead glyphs */ + FT_UShort* Lookahead; /* array of lookahead glyph IDs */ + FT_UShort SubstCount; /* number of SubstLookupRecords */ + TTO_SubstLookupRecord* SubstLookupRecord; + /* array of SubstLookupRecords */ + }; + + typedef struct TTO_ChainSubRule_ TTO_ChainSubRule; + + + struct TTO_ChainSubRuleSet_ + { + FT_UShort ChainSubRuleCount; + /* number of ChainSubRule tables */ + TTO_ChainSubRule* ChainSubRule; /* array of ChainSubRule tables */ + }; + + typedef struct TTO_ChainSubRuleSet_ TTO_ChainSubRuleSet; + + + struct TTO_ChainContextSubstFormat1_ + { + TTO_Coverage Coverage; /* Coverage table */ + FT_UShort ChainSubRuleSetCount; + /* number of ChainSubRuleSet tables */ + TTO_ChainSubRuleSet* ChainSubRuleSet; + /* array of ChainSubRuleSet tables */ + }; + + typedef struct TTO_ChainContextSubstFormat1_ TTO_ChainContextSubstFormat1; + + + struct TTO_ChainSubClassRule_ + { + FT_UShort BacktrackGlyphCount; + /* total number of backtrack + classes */ + FT_UShort* Backtrack; /* array of backtrack classes */ + FT_UShort InputGlyphCount; + /* total number of context classes */ + FT_UShort* Input; /* array of context classes */ + FT_UShort LookaheadGlyphCount; + /* total number of lookahead + classes */ + FT_UShort* Lookahead; /* array of lookahead classes */ + FT_UShort SubstCount; /* number of SubstLookupRecords */ + TTO_SubstLookupRecord* SubstLookupRecord; + /* array of substitution lookups */ + }; + + typedef struct TTO_ChainSubClassRule_ TTO_ChainSubClassRule; + + + struct TTO_ChainSubClassSet_ + { + FT_UShort ChainSubClassRuleCount; + /* number of ChainSubClassRule + tables */ + TTO_ChainSubClassRule* ChainSubClassRule; + /* array of ChainSubClassRule + tables */ + }; + + typedef struct TTO_ChainSubClassSet_ TTO_ChainSubClassSet; + + + /* The `MaxXXXLength' fields are not defined in the TTO specification + but simplifies the implementation of this format. It holds the + maximal context length used in the specific context rules. */ + + struct TTO_ChainContextSubstFormat2_ + { + TTO_Coverage Coverage; /* Coverage table */ + + FT_UShort MaxBacktrackLength; + /* maximal backtrack length */ + TTO_ClassDefinition BacktrackClassDef; + /* BacktrackClassDef table */ + FT_UShort MaxInputLength; + /* maximal input length */ + TTO_ClassDefinition InputClassDef; + /* InputClassDef table */ + FT_UShort MaxLookaheadLength; + /* maximal lookahead length */ + TTO_ClassDefinition LookaheadClassDef; + /* LookaheadClassDef table */ + + FT_UShort ChainSubClassSetCount; + /* number of ChainSubClassSet + tables */ + TTO_ChainSubClassSet* ChainSubClassSet; + /* array of ChainSubClassSet + tables */ + }; + + typedef struct TTO_ChainContextSubstFormat2_ TTO_ChainContextSubstFormat2; + + + struct TTO_ChainContextSubstFormat3_ + { + FT_UShort BacktrackGlyphCount; + /* number of backtrack glyphs */ + TTO_Coverage* BacktrackCoverage; + /* array of backtrack Coverage + tables */ + FT_UShort InputGlyphCount; + /* number of input glyphs */ + TTO_Coverage* InputCoverage; + /* array of input coverage + tables */ + FT_UShort LookaheadGlyphCount; + /* number of lookahead glyphs */ + TTO_Coverage* LookaheadCoverage; + /* array of lookahead coverage + tables */ + FT_UShort SubstCount; /* number of SubstLookupRecords */ + TTO_SubstLookupRecord* SubstLookupRecord; + /* array of substitution lookups */ + }; + + typedef struct TTO_ChainContextSubstFormat3_ TTO_ChainContextSubstFormat3; + + + struct TTO_ChainContextSubst_ + { + FT_UShort SubstFormat; /* 1, 2, or 3 */ + + union + { + TTO_ChainContextSubstFormat1 ccsf1; + TTO_ChainContextSubstFormat2 ccsf2; + TTO_ChainContextSubstFormat3 ccsf3; + } ccsf; + }; + + typedef struct TTO_ChainContextSubst_ TTO_ChainContextSubst; + + + union TTO_GSUB_SubTable_ + { + TTO_SingleSubst single; + TTO_MultipleSubst multiple; + TTO_AlternateSubst alternate; + TTO_LigatureSubst ligature; + TTO_ContextSubst context; + TTO_ChainContextSubst chain; + }; + + typedef union TTO_GSUB_SubTable_ TTO_GSUB_SubTable; + + + /* A simple string object. It can both `send' and `receive' data. + In case of sending, `length' and `pos' will be used. In case of + receiving, `pos' points to the first free slot, and `allocated' + specifies the amount of allocated memory (and the `length' field + will be ignored). The routine TT_Add_String() will increase the + amount of memory if necessary. After end of receive, `length' + should be set to the value of `pos', and `pos' will be set to zero. + + `properties' (which is treated as a bit field) gives the glyph's + properties: If a certain bit is set for a glyph, the feature which + has the same bit set in its property value is applied. + + `components' is an internal array which tracks components of + ligatures. We need this for MarkToLigature Attachment Positioning + Subtables (in GPOS) together with `ligIDs' (which is used to mark + ligatures and the skipped glyphs during a ligature lookup). + `max_ligID' is increased after a successful ligature lookup. + + NEVER modify any elements of the structure! You should rather copy + its contents if necessary. + + TT_Add_String() will also handle allocation; you should use + free() in case you want to destroy the arrays in the object. */ + + struct TTO_GSUB_String_ + { + FT_Memory memory; + + FT_ULong length; + FT_ULong pos; + FT_ULong allocated; + FT_UShort* string; + FT_UShort* properties; + FT_UShort* components; + FT_UShort max_ligID; + FT_UShort* ligIDs; + FT_Int* logClusters; + }; + + typedef struct TTO_GSUB_String_ TTO_GSUB_String; + + + /* finally, the GSUB API */ + + /* EXPORT_DEF + TT_Error TT_Init_GSUB_Extension( TT_Engine engine ); */ + + EXPORT_DEF + FT_Error TT_Load_GSUB_Table( FT_Face face, + TTO_GSUBHeader** gsub, + TTO_GDEFHeader* gdef ); + + EXPORT_DEF + FT_Error TT_Done_GSUB_Table( TTO_GSUBHeader* gsub ); + + EXPORT_DEF + FT_Error TT_GSUB_Select_Script( TTO_GSUBHeader* gsub, + FT_ULong script_tag, + FT_UShort* script_index ); + EXPORT_DEF + FT_Error TT_GSUB_Select_Language( TTO_GSUBHeader* gsub, + FT_ULong language_tag, + FT_UShort script_index, + FT_UShort* language_index, + FT_UShort* req_feature_index ); + EXPORT_DEF + FT_Error TT_GSUB_Select_Feature( TTO_GSUBHeader* gsub, + FT_ULong feature_tag, + FT_UShort script_index, + FT_UShort language_index, + FT_UShort* feature_index ); + + EXPORT_DEF + FT_Error TT_GSUB_Query_Scripts( TTO_GSUBHeader* gsub, + FT_ULong** script_tag_list ); + EXPORT_DEF + FT_Error TT_GSUB_Query_Languages( TTO_GSUBHeader* gsub, + FT_UShort script_index, + FT_ULong** language_tag_list ); + EXPORT_DEF + FT_Error TT_GSUB_Query_Features( TTO_GSUBHeader* gsub, + FT_UShort script_index, + FT_UShort language_index, + FT_ULong** feature_tag_list ); + + EXPORT_DEF + FT_Error TT_GSUB_Add_Feature( TTO_GSUBHeader* gsub, + FT_UShort feature_index, + FT_UShort property ); + EXPORT_DEF + FT_Error TT_GSUB_Clear_Features( TTO_GSUBHeader* gsub ); + + EXPORT_DEF + FT_Error TT_GSUB_Register_Alternate_Function( TTO_GSUBHeader* gsub, + TTO_AltFunction altfunc, + void* data ); + + EXPORT_DEF + FT_Error TT_GSUB_String_New( FT_Memory memory, + TTO_GSUB_String **result ); + + EXPORT_DEF + FT_Error TT_GSUB_String_Set_Length( TTO_GSUB_String *str, + FT_ULong new_length); + + EXPORT_DEF + FT_Error TT_GSUB_String_Done( TTO_GSUB_String *str ); + + + EXPORT_DEF + FT_Error TT_GSUB_Apply_String( TTO_GSUBHeader* gsub, + TTO_GSUB_String* in, + TTO_GSUB_String* out ); + + EXPORT_DEF + FT_Error TT_GSUB_Add_String( TTO_GSUB_String* in, + FT_UShort num_in, + TTO_GSUB_String* out, + FT_UShort num_out, + FT_UShort* glyph_data, + FT_UShort component, + FT_UShort ligID ); + +#ifdef __cplusplus +} +#endif + +#endif /* FTXGSUB_H */ + + +/* END */ |