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freetype/lib/extend/ftxgpos.h
2023-08-27 18:03:45 +02:00

768 lines
25 KiB
C

/*******************************************************************
*
* ftxgpos.h
*
* TrueType Open GPOS table support
*
* Copyright 1996-1999 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 FTXGPOS_H
#define FTXGPOS_H
#ifdef __cplusplus
extern "C" {
#endif
#define TTO_Err_Invalid_GPOS_SubTable_Format 0x1020
#define TTO_Err_Invalid_GPOS_SubTable 0x1021
/* Lookup types for glyph positioning */
#define GPOS_LOOKUP_SINGLE 1
#define GPOS_LOOKUP_PAIR 2
#define GPOS_LOOKUP_CURSIVE 3
#define GPOS_LOOKUP_MARKBASE 4
#define GPOS_LOOKUP_MARKLIG 5
#define GPOS_LOOKUP_MARKMARK 6
#define GPOS_LOOKUP_CONTEXT 7
#define GPOS_LOOKUP_CHAIN 8
struct TTO_GPOSHeader_
{
TT_Bool loaded;
TT_ULong offset;
TT_Fixed Version;
TTO_ScriptList ScriptList;
TTO_FeatureList FeatureList;
TTO_LookupList LookupList;
TTO_GDEFHeader* gdef;
};
typedef struct TTO_GPOSHeader_ TTO_GPOSHeader;
/* shared tables */
struct TTO_ValueRecord_
{
TT_Short XPlacement; /* horizontal adjustment for
placement */
TT_Short YPlacement; /* vertical adjustment for
placement */
TT_Short XAdvance; /* horizontal adjustment for
advance */
TT_Short YAdvance; /* vertical adjustment for
advance */
TTO_Device XPlacementDevice; /* device table for horizontal
placement */
TTO_Device YPlacementDevice; /* device table for vertical
placement */
TTO_Device XAdvanceDevice; /* device table for horizontal
advance */
TTO_Device YAdvanceDevice; /* device table for vertical
advance */
TT_UShort XIdPlacement; /* horizontal placement metric ID */
TT_UShort YIdPlacement; /* vertical placement metric ID */
TT_UShort XIdAdvance; /* horizontal advance metric ID */
TT_UShort YIdAdvance; /* vertical advance metric ID */
};
typedef struct TTO_ValueRecord_ TTO_ValueRecord;
/* Mask values to scan the value format of the ValueRecord structure.
We always expand compressed ValueRecords of the font. */
#define HAVE_X_PLACEMENT 0x0001
#define HAVE_Y_PLACEMENT 0x0002
#define HAVE_X_ADVANCE 0x0004
#define HAVE_Y_ADVANCE 0x0008
#define HAVE_X_PLACEMENT_DEVICE 0x0010
#define HAVE_Y_PLACEMENT_DEVICE 0x0020
#define HAVE_X_ADVANCE_DEVICE 0x0040
#define HAVE_Y_ADVANCE_DEVICE 0x0080
#define HAVE_X_ID_PLACEMENT 0x0100
#define HAVE_Y_ID_PLACEMENT 0x0200
#define HAVE_X_ID_ADVANCE 0x0400
#define HAVE_Y_ID_ADVANCE 0x0800
struct TTO_AnchorFormat1_
{
TT_Short XCoordinate; /* horizontal value */
TT_Short YCoordinate; /* vertical value */
};
typedef struct TTO_AnchorFormat1_ TTO_AnchorFormat1;
struct TTO_AnchorFormat2_
{
TT_Short XCoordinate; /* horizontal value */
TT_Short YCoordinate; /* vertical value */
TT_UShort AnchorPoint; /* index to glyph contour point */
};
typedef struct TTO_AnchorFormat2_ TTO_AnchorFormat2;
struct TTO_AnchorFormat3_
{
TT_Short XCoordinate; /* horizontal value */
TT_Short YCoordinate; /* vertical value */
TTO_Device XDeviceTable; /* device table for X coordinate */
TTO_Device YDeviceTable; /* device table for Y coordinate */
};
typedef struct TTO_AnchorFormat3_ TTO_AnchorFormat3;
struct TTO_AnchorFormat4_
{
TT_UShort XIdAnchor; /* horizontal metric ID */
TT_UShort YIdAnchor; /* vertical metric ID */
};
typedef struct TTO_AnchorFormat4_ TTO_AnchorFormat4;
struct TTO_Anchor_
{
TT_UShort PosFormat; /* 1, 2, 3, or 4 -- 0 indicates
that there is no Anchor table */
union
{
TTO_AnchorFormat1 af1;
TTO_AnchorFormat2 af2;
TTO_AnchorFormat3 af3;
TTO_AnchorFormat4 af4;
} af;
};
typedef struct TTO_Anchor_ TTO_Anchor;
struct TTO_MarkRecord_
{
TT_UShort Class; /* mark class */
TTO_Anchor MarkAnchor; /* anchor table */
};
typedef struct TTO_MarkRecord_ TTO_MarkRecord;
struct TTO_MarkArray_
{
TT_UShort MarkCount; /* number of MarkRecord tables */
TTO_MarkRecord* MarkRecord; /* array of MarkRecord tables */
};
typedef struct TTO_MarkArray_ TTO_MarkArray;
/* LookupType 1 */
struct TTO_SinglePosFormat1_
{
TTO_ValueRecord Value; /* ValueRecord for all covered
glyphs */
};
typedef struct TTO_SinglePosFormat1_ TTO_SinglePosFormat1;
struct TTO_SinglePosFormat2_
{
TT_UShort ValueCount; /* number of ValueRecord tables */
TTO_ValueRecord* Value; /* array of ValueRecord tables */
};
typedef struct TTO_SinglePosFormat2_ TTO_SinglePosFormat2;
struct TTO_SinglePos_
{
TT_UShort PosFormat; /* 1 or 2 */
TTO_Coverage Coverage; /* Coverage table */
TT_UShort ValueFormat; /* format of ValueRecord table */
union
{
TTO_SinglePosFormat1 spf1;
TTO_SinglePosFormat2 spf2;
} spf;
};
typedef struct TTO_SinglePos_ TTO_SinglePos;
/* LookupType 2 */
struct TTO_PairValueRecord_
{
TT_UShort SecondGlyph; /* glyph ID for second glyph */
TTO_ValueRecord Value1; /* pos. data for first glyph */
TTO_ValueRecord Value2; /* pos. data for second glyph */
};
typedef struct TTO_PairValueRecord_ TTO_PairValueRecord;
struct TTO_PairSet_
{
TT_UShort PairValueCount;
/* number of PairValueRecord tables */
TTO_PairValueRecord* PairValueRecord;
/* array of PairValueRecord tables */
};
typedef struct TTO_PairSet_ TTO_PairSet;
struct TTO_PairPosFormat1_
{
TT_UShort PairSetCount; /* number of PairSet tables */
TTO_PairSet* PairSet; /* array of PairSet tables */
};
typedef struct TTO_PairPosFormat1_ TTO_PairPosFormat1;
struct TTO_Class2Record_
{
TTO_ValueRecord Value1; /* pos. data for first glyph */
TTO_ValueRecord Value2; /* pos. data for second glyph */
};
typedef struct TTO_Class2Record_ TTO_Class2Record;
struct TTO_Class1Record_
{
TTO_Class2Record* Class2Record; /* array of Class2Record tables */
};
typedef struct TTO_Class1Record_ TTO_Class1Record;
struct TTO_PairPosFormat2_
{
TTO_ClassDefinition ClassDef1; /* class def. for first glyph */
TTO_ClassDefinition ClassDef2; /* class def. for second glyph */
TT_UShort Class1Count; /* number of classes in ClassDef1
table */
TT_UShort Class2Count; /* number of classes in ClassDef2
table */
TTO_Class1Record* Class1Record; /* array of Class1Record tables */
};
typedef struct TTO_PairPosFormat2_ TTO_PairPosFormat2;
struct TTO_PairPos_
{
TT_UShort PosFormat; /* 1 or 2 */
TTO_Coverage Coverage; /* Coverage table */
TT_UShort ValueFormat1; /* format of ValueRecord table
for first glyph */
TT_UShort ValueFormat2; /* format of ValueRecord table
for second glyph */
union
{
TTO_PairPosFormat1 ppf1;
TTO_PairPosFormat2 ppf2;
} ppf;
};
typedef struct TTO_PairPos_ TTO_PairPos;
/* LookupType 3 */
struct TTO_EntryExitRecord_
{
TTO_Anchor EntryAnchor; /* entry Anchor table */
TTO_Anchor ExitAnchor; /* exit Anchor table */
};
typedef struct TTO_EntryExitRecord_ TTO_EntryExitRecord;
struct TTO_CursivePos_
{
TT_UShort PosFormat; /* always 1 */
TTO_Coverage Coverage; /* Coverage table */
TT_UShort EntryExitCount;
/* number of EntryExitRecord tables */
TTO_EntryExitRecord* EntryExitRecord;
/* array of EntryExitRecord tables */
};
typedef struct TTO_CursivePos_ TTO_CursivePos;
/* LookupType 4 */
struct TTO_BaseRecord_
{
TTO_Anchor* BaseAnchor; /* array of base glyph anchor
tables */
};
typedef struct TTO_BaseRecord_ TTO_BaseRecord;
struct TTO_BaseArray_
{
TT_UShort BaseCount; /* number of BaseRecord tables */
TTO_BaseRecord* BaseRecord; /* array of BaseRecord tables */
};
typedef struct TTO_BaseArray_ TTO_BaseArray;
struct TTO_MarkBasePos_
{
TT_UShort PosFormat; /* always 1 */
TTO_Coverage MarkCoverage; /* mark glyph coverage table */
TTO_Coverage BaseCoverage; /* base glyph coverage table */
TT_UShort ClassCount; /* number of mark classes */
TTO_MarkArray MarkArray; /* mark array table */
TTO_BaseArray BaseArray; /* base array table */
};
typedef struct TTO_MarkBasePos_ TTO_MarkBasePos;
/* LookupType 5 */
struct TTO_ComponentRecord_
{
TTO_Anchor* LigatureAnchor; /* array of ligature glyph anchor
tables */
};
typedef struct TTO_ComponentRecord_ TTO_ComponentRecord;
struct TTO_LigatureAttach_
{
TT_UShort ComponentCount;
/* number of ComponentRecord tables */
TTO_ComponentRecord* ComponentRecord;
/* array of ComponentRecord tables */
};
typedef struct TTO_LigatureAttach_ TTO_LigatureAttach;
struct TTO_LigatureArray_
{
TT_UShort LigatureCount; /* number of LigatureAttach tables */
TTO_LigatureAttach* LigatureAttach;
/* array of LigatureAttach tables */
};
typedef struct TTO_LigatureArray_ TTO_LigatureArray;
struct TTO_MarkLigPos_
{
TT_UShort PosFormat; /* always 1 */
TTO_Coverage MarkCoverage; /* mark glyph coverage table */
TTO_Coverage LigatureCoverage;
/* ligature glyph coverage table */
TT_UShort ClassCount; /* number of mark classes */
TTO_MarkArray MarkArray; /* mark array table */
TTO_LigatureArray LigatureArray; /* ligature array table */
};
typedef struct TTO_MarkLigPos_ TTO_MarkLigPos;
/* LookupType 6 */
struct TTO_Mark2Record_
{
TTO_Anchor* Mark2Anchor; /* array of mark glyph anchor
tables */
};
typedef struct TTO_Mark2Record_ TTO_Mark2Record;
struct TTO_Mark2Array_
{
TT_UShort Mark2Count; /* number of Mark2Record tables */
TTO_Mark2Record* Mark2Record; /* array of Mark2Record tables */
};
typedef struct TTO_Mark2Array_ TTO_Mark2Array;
struct TTO_MarkMarkPos_
{
TT_UShort PosFormat; /* always 1 */
TTO_Coverage Mark1Coverage; /* first mark glyph coverage table */
TTO_Coverage Mark2Coverage; /* second mark glyph coverave table */
TT_UShort ClassCount; /* number of combining mark classes */
TTO_MarkArray Mark1Array; /* MarkArray table for first mark */
TTO_Mark2Array Mark2Array; /* MarkArray table for second mark */
};
typedef struct TTO_MarkMarkPos_ TTO_MarkMarkPos;
/* needed by both lookup type 7 and 8 */
struct TTO_PosLookupRecord_
{
TT_UShort SequenceIndex; /* index into current
glyph sequence */
TT_UShort LookupListIndex; /* Lookup to apply to that pos. */
};
typedef struct TTO_PosLookupRecord_ TTO_PosLookupRecord;
/* LookupType 7 */
struct TTO_PosRule_
{
TT_UShort GlyphCount; /* total number of input glyphs */
TT_UShort PosCount; /* number of PosLookupRecord tables */
TT_UShort* Input; /* array of input glyph IDs */
TTO_PosLookupRecord* PosLookupRecord;
/* array of PosLookupRecord tables */
};
typedef struct TTO_PosRule_ TTO_PosRule;
struct TTO_PosRuleSet_
{
TT_UShort PosRuleCount; /* number of PosRule tables */
TTO_PosRule* PosRule; /* array of PosRule tables */
};
typedef struct TTO_PosRuleSet_ TTO_PosRuleSet;
struct TTO_ContextPosFormat1_
{
TTO_Coverage Coverage; /* Coverage table */
TT_UShort PosRuleSetCount; /* number of PosRuleSet tables */
TTO_PosRuleSet* PosRuleSet; /* array of PosRuleSet tables */
};
typedef struct TTO_ContextPosFormat1_ TTO_ContextPosFormat1;
struct TTO_PosClassRule_
{
TT_UShort GlyphCount; /* total number of context classes */
TT_UShort PosCount; /* number of PosLookupRecord tables */
TT_UShort* Class; /* array of classes */
TTO_PosLookupRecord* PosLookupRecord;
/* array of PosLookupRecord tables */
};
typedef struct TTO_PosClassRule_ TTO_PosClassRule;
struct TTO_PosClassSet_
{
TT_UShort PosClassRuleCount;
/* number of PosClassRule tables */
TTO_PosClassRule* PosClassRule; /* array of PosClassRule tables */
};
typedef struct TTO_PosClassSet_ TTO_PosClassSet;
/* 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_ContextPosFormat2_
{
TT_UShort MaxContextLength;
/* maximal context length */
TTO_Coverage Coverage; /* Coverage table */
TTO_ClassDefinition ClassDef; /* ClassDef table */
TT_UShort PosClassSetCount;
/* number of PosClassSet tables */
TTO_PosClassSet* PosClassSet; /* array of PosClassSet tables */
};
typedef struct TTO_ContextPosFormat2_ TTO_ContextPosFormat2;
struct TTO_ContextPosFormat3_
{
TT_UShort GlyphCount; /* number of input glyphs */
TT_UShort PosCount; /* number of PosLookupRecord tables */
TTO_Coverage* Coverage; /* array of Coverage tables */
TTO_PosLookupRecord* PosLookupRecord;
/* array of PosLookupRecord tables */
};
typedef struct TTO_ContextPosFormat3_ TTO_ContextPosFormat3;
struct TTO_ContextPos_
{
TT_UShort PosFormat; /* 1, 2, or 3 */
union
{
TTO_ContextPosFormat1 cpf1;
TTO_ContextPosFormat2 cpf2;
TTO_ContextPosFormat3 cpf3;
} cpf;
};
typedef struct TTO_ContextPos_ TTO_ContextPos;
/* LookupType 8 */
struct TTO_ChainPosRule_
{
TT_UShort BacktrackGlyphCount;
/* total number of backtrack glyphs */
TT_UShort* Backtrack; /* array of backtrack glyph IDs */
TT_UShort InputGlyphCount;
/* total number of input glyphs */
TT_UShort* Input; /* array of input glyph IDs */
TT_UShort LookaheadGlyphCount;
/* total number of lookahead glyphs */
TT_UShort* Lookahead; /* array of lookahead glyph IDs */
TT_UShort PosCount; /* number of PosLookupRecords */
TTO_PosLookupRecord* PosLookupRecord;
/* array of PosLookupRecords */
};
typedef struct TTO_ChainPosRule_ TTO_ChainPosRule;
struct TTO_ChainPosRuleSet_
{
TT_UShort ChainPosRuleCount;
/* number of ChainPosRule tables */
TTO_ChainPosRule* ChainPosRule; /* array of ChainPosRule tables */
};
typedef struct TTO_ChainPosRuleSet_ TTO_ChainPosRuleSet;
struct TTO_ChainContextPosFormat1_
{
TTO_Coverage Coverage; /* Coverage table */
TT_UShort ChainPosRuleSetCount;
/* number of ChainPosRuleSet tables */
TTO_ChainPosRuleSet* ChainPosRuleSet;
/* array of ChainPosRuleSet tables */
};
typedef struct TTO_ChainContextPosFormat1_ TTO_ChainContextPosFormat1;
struct TTO_ChainPosClassRule_
{
TT_UShort BacktrackGlyphCount;
/* total number of backtrack
classes */
TT_UShort* Backtrack; /* array of backtrack classes */
TT_UShort InputGlyphCount;
/* total number of context classes */
TT_UShort* Input; /* array of context classes */
TT_UShort LookaheadGlyphCount;
/* total number of lookahead
classes */
TT_UShort* Lookahead; /* array of lookahead classes */
TT_UShort PosCount; /* number of PosLookupRecords */
TTO_PosLookupRecord* PosLookupRecord;
/* array of substitution lookups */
};
typedef struct TTO_ChainPosClassRule_ TTO_ChainPosClassRule;
struct TTO_ChainPosClassSet_
{
TT_UShort ChainPosClassRuleCount;
/* number of ChainPosClassRule
tables */
TTO_ChainPosClassRule* ChainPosClassRule;
/* array of ChainPosClassRule
tables */
};
typedef struct TTO_ChainPosClassSet_ TTO_ChainPosClassSet;
/* 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_ChainContextPosFormat2_
{
TTO_Coverage Coverage; /* Coverage table */
TT_UShort MaxBacktrackLength;
/* maximal backtrack length */
TTO_ClassDefinition BacktrackClassDef;
/* BacktrackClassDef table */
TT_UShort MaxInputLength;
/* maximal input length */
TTO_ClassDefinition InputClassDef;
/* InputClassDef table */
TT_UShort MaxLookaheadLength;
/* maximal lookahead length */
TTO_ClassDefinition LookaheadClassDef;
/* LookaheadClassDef table */
TT_UShort ChainPosClassSetCount;
/* number of ChainPosClassSet
tables */
TTO_ChainPosClassSet* ChainPosClassSet;
/* array of ChainPosClassSet
tables */
};
typedef struct TTO_ChainContextPosFormat2_ TTO_ChainContextPosFormat2;
struct TTO_ChainContextPosFormat3_
{
TT_UShort BacktrackGlyphCount;
/* number of backtrack glyphs */
TTO_Coverage* BacktrackCoverage;
/* array of backtrack Coverage
tables */
TT_UShort InputGlyphCount;
/* number of input glyphs */
TTO_Coverage* InputCoverage;
/* array of input coverage
tables */
TT_UShort LookaheadGlyphCount;
/* number of lookahead glyphs */
TTO_Coverage* LookaheadCoverage;
/* array of lookahead coverage
tables */
TT_UShort PosCount; /* number of PosLookupRecords */
TTO_PosLookupRecord* PosLookupRecord;
/* array of substitution lookups */
};
typedef struct TTO_ChainContextPosFormat3_ TTO_ChainContextPosFormat3;
struct TTO_ChainContextPos_
{
TT_UShort PosFormat; /* 1, 2, or 3 */
union
{
TTO_ChainContextPosFormat1 ccpf1;
TTO_ChainContextPosFormat2 ccpf2;
TTO_ChainContextPosFormat3 ccpf3;
} ccpf;
};
typedef struct TTO_ChainContextPos_ TTO_ChainContextPos;
union TTO_GPOS_SubTable_
{
TTO_SinglePos single;
TTO_PairPos pair;
TTO_CursivePos cursive;
TTO_MarkBasePos markbase;
TTO_MarkLigPos marklig;
TTO_MarkMarkPos markmark;
TTO_ContextPos context;
TTO_ChainContextPos chain;
};
typedef union TTO_GPOS_SubTable_ TTO_GPOS_SubTable;
/* finally, the GPOS API */
EXPORT_DEF
TT_Error TT_Init_GPOS_Extension( TT_Engine engine );
EXPORT_DEF
TT_Error TT_Load_GPOS_Table( TT_Face face,
TTO_GPOSHeader* gpos,
TTO_GDEFHeader* gdef );
EXPORT_DEF
TT_Error TT_GPOS_Select_Script( TTO_GPOSHeader* gpos,
TT_ULong script_tag,
TT_UShort* script_index );
EXPORT_DEF
TT_Error TT_GPOS_Select_Language( TTO_GPOSHeader* gpos,
TT_ULong language_tag,
TT_UShort script_index,
TT_UShort* language_index,
TT_UShort* req_feature_index );
EXPORT_DEF
TT_Error TT_GPOS_Select_Feature( TTO_GPOSHeader* gpos,
TT_ULong feature_tag,
TT_UShort script_index,
TT_UShort language_index,
TT_UShort* feature_index );
EXPORT_DEF
TT_Error TT_GPOS_Query_Scripts( TTO_GPOSHeader* gpos,
TT_ULong** script_tag_list );
EXPORT_DEF
TT_Error TT_GPOS_Query_Languages( TTO_GPOSHeader* gpos,
TT_UShort script_index,
TT_ULong** language_tag_list );
EXPORT_DEF
TT_Error TT_GPOS_Query_Features( TTO_GPOSHeader* gpos,
TT_UShort script_index,
TT_UShort language_index,
TT_ULong** feature_tag_list );
EXPORT_DEF
TT_Error TT_GPOS_Add_Feature( TTO_GPOSHeader* gpos,
TT_UShort feature_index,
TT_UShort property );
EXPORT_DEF
TT_Error TT_GPOS_Clear_Features( TTO_GPOSHeader* gpos );
#ifdef __cplusplus
}
#endif
#endif /* FTXGPOS_H */
/* END */