| /******************************************************************* |
| * |
| * 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 |
| |
| |
| /* 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 */ |
