src/3rdparty/harfbuzz/src/harfbuzz-gpos-private.h

   1 /*
   2  * Copyright (C) 1998-2004  David Turner and Werner Lemberg
   3  * Copyright (C) 2006  Behdad Esfahbod
   4  *
   5  * This is part of HarfBuzz, an OpenType Layout engine library.
   6  *
   7  * Permission is hereby granted, without written agreement and without
   8  * license or royalty fees, to use, copy, modify, and distribute this
   9  * software and its documentation for any purpose, provided that the
  10  * above copyright notice and the following two paragraphs appear in
  11  * all copies of this software.
  12  *
  13  * IN NO EVENT SHALL THE COPYRIGHT HOLDER BE LIABLE TO ANY PARTY FOR
  14  * DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES
  15  * ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN
  16  * IF THE COPYRIGHT HOLDER HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH
  17  * DAMAGE.
  18  *
  19  * THE COPYRIGHT HOLDER SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING,
  20  * BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
  21  * FITNESS FOR A PARTICULAR PURPOSE.  THE SOFTWARE PROVIDED HEREUNDER IS
  22  * ON AN "AS IS" BASIS, AND THE COPYRIGHT HOLDER HAS NO OBLIGATION TO
  23  * PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.
  24  */
  25
  26 #ifndef HARFBUZZ_GPOS_PRIVATE_H
  27 #define HARFBUZZ_GPOS_PRIVATE_H
  28
  29 #include "harfbuzz-impl.h"
  30 #include "harfbuzz-stream-private.h"
  31 #include "harfbuzz-gpos.h"
  32
  33 HB_BEGIN_HEADER
  34
  35 /* shared tables */
  36
  37 #define VR_X_PLACEMENT_DEVICE 0
  38 #define VR_Y_PLACEMENT_DEVICE 1
  39 #define VR_X_ADVANCE_DEVICE   2
  40 #define VR_Y_ADVANCE_DEVICE   3
  41
  42 #ifndef HB_SUPPORT_MULTIPLE_MASTER
  43 #  define HB_USE_FLEXIBLE_VALUE_RECORD
  44 #endif
  45
  46 struct  HB_ValueRecord_
  47 {
  48   HB_Short    XPlacement;             /* horizontal adjustment for
  49                                          placement                      */
  50   HB_Short    YPlacement;             /* vertical adjustment for
  51                                          placement                      */
  52   HB_Short    XAdvance;               /* horizontal adjustment for
  53                                          advance                        */
  54   HB_Short    YAdvance;               /* vertical adjustment for
  55                                          advance                        */
  56
  57   HB_Device** DeviceTables;           /* device tables for placement
  58                                          and advance                    */
  59
  60 #ifdef HB_SUPPORT_MULTIPLE_MASTER
  61   HB_UShort   XIdPlacement;           /* horizontal placement metric ID */
  62   HB_UShort   YIdPlacement;           /* vertical placement metric ID   */
  63   HB_UShort   XIdAdvance;             /* horizontal advance metric ID   */
  64   HB_UShort   YIdAdvance;             /* vertical advance metric ID     */
  65 #endif
  66 };
  67
  68 typedef struct HB_ValueRecord_  HB_ValueRecord;
  69
  70
  71 /* Mask values to scan the value format of the ValueRecord structure.
  72  We always expand compressed ValueRecords of the font.              */
  73
  74 #define HB_GPOS_FORMAT_HAVE_DEVICE_TABLES       0x00F0
  75
  76 #define HB_GPOS_FORMAT_HAVE_X_PLACEMENT         0x0001
  77 #define HB_GPOS_FORMAT_HAVE_Y_PLACEMENT         0x0002
  78 #define HB_GPOS_FORMAT_HAVE_X_ADVANCE           0x0004
  79 #define HB_GPOS_FORMAT_HAVE_Y_ADVANCE           0x0008
  80 #define HB_GPOS_FORMAT_HAVE_X_PLACEMENT_DEVICE  0x0010
  81 #define HB_GPOS_FORMAT_HAVE_Y_PLACEMENT_DEVICE  0x0020
  82 #define HB_GPOS_FORMAT_HAVE_X_ADVANCE_DEVICE    0x0040
  83 #define HB_GPOS_FORMAT_HAVE_Y_ADVANCE_DEVICE    0x0080
  84 #define HB_GPOS_FORMAT_HAVE_X_ID_PLACEMENT      0x0100
  85 #define HB_GPOS_FORMAT_HAVE_Y_ID_PLACEMENT      0x0200
  86 #define HB_GPOS_FORMAT_HAVE_X_ID_ADVANCE        0x0400
  87 #define HB_GPOS_FORMAT_HAVE_Y_ID_ADVANCE        0x0800
  88
  89
  90 struct  HB_AnchorFormat1_
  91 {
  92   HB_Short   XCoordinate;             /* horizontal value */
  93   HB_Short   YCoordinate;             /* vertical value   */
  94 };
  95
  96 typedef struct HB_AnchorFormat1_  HB_AnchorFormat1;
  97
  98
  99 struct  HB_AnchorFormat2_
 100 {
 101   HB_Short   XCoordinate;             /* horizontal value             */
 102   HB_Short   YCoordinate;             /* vertical value               */
 103   HB_UShort  AnchorPoint;             /* index to glyph contour point */
 104 };
 105
 106 typedef struct HB_AnchorFormat2_  HB_AnchorFormat2;
 107
 108 #define AF3_X_DEVICE_TABLE 0
 109 #define AF3_Y_DEVICE_TABLE 1
 110
 111 struct  HB_AnchorFormat3_
 112 {
 113   HB_Short    XCoordinate;            /* horizontal value              */
 114   HB_Short    YCoordinate;            /* vertical value                */
 115   HB_Device** DeviceTables;           /* device tables for coordinates */
 116 };
 117
 118 typedef struct HB_AnchorFormat3_  HB_AnchorFormat3;
 119
 120
 121 #ifdef HB_SUPPORT_MULTIPLE_MASTER
 122 struct  HB_AnchorFormat4_
 123 {
 124   HB_UShort  XIdAnchor;               /* horizontal metric ID */
 125   HB_UShort  YIdAnchor;               /* vertical metric ID   */
 126 };
 127
 128 typedef struct HB_AnchorFormat4_  HB_AnchorFormat4;
 129 #endif
 130
 131
 132 struct  HB_Anchor_
 133 {
 134   HB_Byte  PosFormat;                 /* 1, 2, 3, or 4 -- 0 indicates
 135                                          that there is no Anchor table */
 136
 137   union
 138   {
 139     HB_AnchorFormat1  af1;
 140     HB_AnchorFormat2  af2;
 141     HB_AnchorFormat3  af3;
 142 #ifdef HB_SUPPORT_MULTIPLE_MASTER
 143     HB_AnchorFormat4  af4;
 144 #endif
 145   } af;
 146 };
 147
 148 typedef struct HB_Anchor_  HB_Anchor;
 149
 150
 151 struct  HB_MarkRecord_
 152 {
 153   HB_UShort   Class;                  /* mark class   */
 154   HB_Anchor  MarkAnchor;             /* anchor table */
 155 };
 156
 157 typedef struct HB_MarkRecord_  HB_MarkRecord;
 158
 159
 160 struct  HB_MarkArray_
 161 {
 162   HB_UShort        MarkCount;         /* number of MarkRecord tables */
 163   HB_MarkRecord*  MarkRecord;        /* array of MarkRecord tables  */
 164 };
 165
 166 typedef struct HB_MarkArray_  HB_MarkArray;
 167
 168
 169 /* LookupType 1 */
 170
 171 struct  HB_SinglePosFormat1_
 172 {
 173   HB_ValueRecord  Value;             /* ValueRecord for all covered
 174                                          glyphs                      */
 175 };
 176
 177 typedef struct HB_SinglePosFormat1_  HB_SinglePosFormat1;
 178
 179
 180 struct  HB_SinglePosFormat2_
 181 {
 182   HB_UShort         ValueCount;       /* number of ValueRecord tables */
 183   HB_ValueRecord*  Value;            /* array of ValueRecord tables  */
 184 };
 185
 186 typedef struct HB_SinglePosFormat2_  HB_SinglePosFormat2;
 187
 188
 189 struct  HB_SinglePos_
 190 {
 191   HB_Byte       PosFormat;            /* 1 or 2         */
 192   HB_Coverage  Coverage;             /* Coverage table */
 193
 194   HB_UShort     ValueFormat;          /* format of ValueRecord table */
 195
 196   union
 197   {
 198     HB_SinglePosFormat1  spf1;
 199     HB_SinglePosFormat2  spf2;
 200   } spf;
 201 };
 202
 203 typedef struct HB_SinglePos_  HB_SinglePos;
 204
 205
 206 /* LookupType 2 */
 207
 208 struct  HB_PairValueRecord_
 209 {
 210   HB_UShort        SecondGlyph;       /* glyph ID for second glyph  */
 211   HB_ValueRecord  Value1;            /* pos. data for first glyph  */
 212   HB_ValueRecord  Value2;            /* pos. data for second glyph */
 213 };
 214
 215 typedef struct HB_PairValueRecord_  HB_PairValueRecord;
 216
 217
 218 struct  HB_PairSet_
 219 {
 220   HB_UShort             PairValueCount;
 221                                       /* number of PairValueRecord tables */
 222   HB_PairValueRecord*  PairValueRecord;
 223                                       /* array of PairValueRecord tables  */
 224 };
 225
 226 typedef struct HB_PairSet_  HB_PairSet;
 227
 228
 229 struct  HB_PairPosFormat1_
 230 {
 231   HB_UShort     PairSetCount;         /* number of PairSet tables    */
 232   HB_PairSet*  PairSet;              /* array of PairSet tables     */
 233 };
 234
 235 typedef struct HB_PairPosFormat1_  HB_PairPosFormat1;
 236
 237
 238 struct  HB_Class2Record_
 239 {
 240   HB_ValueRecord  Value1;            /* pos. data for first glyph  */
 241   HB_ValueRecord  Value2;            /* pos. data for second glyph */
 242 };
 243
 244 typedef struct HB_Class2Record_  HB_Class2Record;
 245
 246
 247 struct  HB_Class1Record_
 248 {
 249   hb_uint8 IsFlexible;
 250   union {
 251     HB_Class2Record*  Class2Record;    /* array of Class2Record tables */
 252     HB_Short* ValueRecords;
 253   } c2r;
 254 };
 255
 256 typedef struct HB_Class1Record_  HB_Class1Record;
 257
 258
 259 struct  HB_PairPosFormat2_
 260 {
 261   HB_ClassDefinition  ClassDef1;     /* class def. for first glyph     */
 262   HB_ClassDefinition  ClassDef2;     /* class def. for second glyph    */
 263   HB_UShort            Class1Count;   /* number of classes in ClassDef1
 264                                          table                          */
 265   HB_UShort            Class2Count;   /* number of classes in ClassDef2
 266                                          table                          */
 267   HB_Class1Record*    Class1Record;  /* array of Class1Record tables   */
 268 };
 269
 270 typedef struct HB_PairPosFormat2_  HB_PairPosFormat2;
 271
 272
 273 struct  HB_PairPos_
 274 {
 275   HB_Byte       PosFormat;            /* 1 or 2         */
 276   HB_Coverage  Coverage;             /* Coverage table */
 277   HB_UShort     ValueFormat1;         /* format of ValueRecord table
 278                                          for first glyph             */
 279   HB_UShort     ValueFormat2;         /* format of ValueRecord table
 280                                          for second glyph            */
 281
 282   union
 283   {
 284     HB_PairPosFormat1  ppf1;
 285     HB_PairPosFormat2  ppf2;
 286   } ppf;
 287 };
 288
 289 typedef struct HB_PairPos_  HB_PairPos;
 290
 291
 292 /* LookupType 3 */
 293
 294 struct  HB_EntryExitRecord_
 295 {
 296   HB_Anchor  EntryAnchor;            /* entry Anchor table */
 297   HB_Anchor  ExitAnchor;             /* exit Anchor table  */
 298 };
 299
 300
 301 typedef struct HB_EntryExitRecord_  HB_EntryExitRecord;
 302
 303 struct  HB_CursivePos_
 304 {
 305   HB_UShort             PosFormat;    /* always 1                         */
 306   HB_Coverage          Coverage;     /* Coverage table                   */
 307   HB_UShort             EntryExitCount;
 308                                       /* number of EntryExitRecord tables */
 309   HB_EntryExitRecord*  EntryExitRecord;
 310                                       /* array of EntryExitRecord tables  */
 311 };
 312
 313 typedef struct HB_CursivePos_  HB_CursivePos;
 314
 315
 316 /* LookupType 4 */
 317
 318 struct  HB_BaseRecord_
 319 {
 320   HB_Anchor*  BaseAnchor;            /* array of base glyph anchor
 321                                          tables                     */
 322 };
 323
 324 typedef struct HB_BaseRecord_  HB_BaseRecord;
 325
 326
 327 struct  HB_BaseArray_
 328 {
 329   HB_UShort        BaseCount;         /* number of BaseRecord tables */
 330   HB_BaseRecord*  BaseRecord;        /* array of BaseRecord tables  */
 331 };
 332
 333 typedef struct HB_BaseArray_  HB_BaseArray;
 334
 335
 336 struct  HB_MarkBasePos_
 337 {
 338   HB_UShort      PosFormat;           /* always 1                  */
 339   HB_Coverage   MarkCoverage;        /* mark glyph coverage table */
 340   HB_Coverage   BaseCoverage;        /* base glyph coverage table */
 341   HB_UShort      ClassCount;          /* number of mark classes    */
 342   HB_MarkArray  MarkArray;           /* mark array table          */
 343   HB_BaseArray  BaseArray;           /* base array table          */
 344 };
 345
 346 typedef struct HB_MarkBasePos_  HB_MarkBasePos;
 347
 348
 349 /* LookupType 5 */
 350
 351 struct  HB_ComponentRecord_
 352 {
 353   HB_Anchor*  LigatureAnchor;        /* array of ligature glyph anchor
 354                                          tables                         */
 355 };
 356
 357 typedef struct HB_ComponentRecord_  HB_ComponentRecord;
 358
 359
 360 struct  HB_LigatureAttach_
 361 {
 362   HB_UShort             ComponentCount;
 363                                       /* number of ComponentRecord tables */
 364   HB_ComponentRecord*  ComponentRecord;
 365                                       /* array of ComponentRecord tables  */
 366 };
 367
 368 typedef struct HB_LigatureAttach_  HB_LigatureAttach;
 369
 370
 371 struct  HB_LigatureArray_
 372 {
 373   HB_UShort            LigatureCount; /* number of LigatureAttach tables */
 374   HB_LigatureAttach*  LigatureAttach;
 375                                       /* array of LigatureAttach tables  */
 376 };
 377
 378 typedef struct HB_LigatureArray_  HB_LigatureArray;
 379
 380
 381 struct  HB_MarkLigPos_
 382 {
 383   HB_UShort          PosFormat;       /* always 1                      */
 384   HB_Coverage       MarkCoverage;    /* mark glyph coverage table     */
 385   HB_Coverage       LigatureCoverage;
 386                                       /* ligature glyph coverage table */
 387   HB_UShort          ClassCount;      /* number of mark classes        */
 388   HB_MarkArray      MarkArray;       /* mark array table              */
 389   HB_LigatureArray  LigatureArray;   /* ligature array table          */
 390 };
 391
 392 typedef struct HB_MarkLigPos_  HB_MarkLigPos;
 393
 394
 395 /* LookupType 6 */
 396
 397 struct  HB_Mark2Record_
 398 {
 399   HB_Anchor*  Mark2Anchor;           /* array of mark glyph anchor
 400                                          tables                     */
 401 };
 402
 403 typedef struct HB_Mark2Record_  HB_Mark2Record;
 404
 405
 406 struct  HB_Mark2Array_
 407 {
 408   HB_UShort         Mark2Count;       /* number of Mark2Record tables */
 409   HB_Mark2Record*  Mark2Record;      /* array of Mark2Record tables  */
 410 };
 411
 412 typedef struct HB_Mark2Array_  HB_Mark2Array;
 413
 414
 415 struct  HB_MarkMarkPos_
 416 {
 417   HB_UShort       PosFormat;          /* always 1                         */
 418   HB_Coverage    Mark1Coverage;      /* first mark glyph coverage table  */
 419   HB_Coverage    Mark2Coverage;      /* second mark glyph coverave table */
 420   HB_UShort       ClassCount;         /* number of combining mark classes */
 421   HB_MarkArray   Mark1Array;         /* MarkArray table for first mark   */
 422   HB_Mark2Array  Mark2Array;         /* MarkArray table for second mark  */
 423 };
 424
 425 typedef struct HB_MarkMarkPos_  HB_MarkMarkPos;
 426
 427
 428 /* needed by both lookup type 7 and 8 */
 429
 430 struct  HB_PosLookupRecord_
 431 {
 432   HB_UShort  SequenceIndex;           /* index into current
 433                                          glyph sequence               */
 434   HB_UShort  LookupListIndex;         /* Lookup to apply to that pos. */
 435 };
 436
 437 typedef struct HB_PosLookupRecord_  HB_PosLookupRecord;
 438
 439
 440 /* LookupType 7 */
 441
 442 struct  HB_PosRule_
 443 {
 444   HB_UShort             GlyphCount;   /* total number of input glyphs     */
 445   HB_UShort             PosCount;     /* number of PosLookupRecord tables */
 446   HB_UShort*            Input;        /* array of input glyph IDs         */
 447   HB_PosLookupRecord*  PosLookupRecord;
 448                                       /* array of PosLookupRecord tables  */
 449 };
 450
 451 typedef struct HB_PosRule_  HB_PosRule;
 452
 453
 454 struct  HB_PosRuleSet_
 455 {
 456   HB_UShort     PosRuleCount;         /* number of PosRule tables */
 457   HB_PosRule*  PosRule;              /* array of PosRule tables  */
 458 };
 459
 460 typedef struct HB_PosRuleSet_  HB_PosRuleSet;
 461
 462
 463 struct  HB_ContextPosFormat1_
 464 {
 465   HB_Coverage     Coverage;          /* Coverage table              */
 466   HB_UShort        PosRuleSetCount;   /* number of PosRuleSet tables */
 467   HB_PosRuleSet*  PosRuleSet;        /* array of PosRuleSet tables  */
 468 };
 469
 470 typedef struct HB_ContextPosFormat1_  HB_ContextPosFormat1;
 471
 472
 473 struct  HB_PosClassRule_
 474 {
 475   HB_UShort             GlyphCount;   /* total number of context classes  */
 476   HB_UShort             PosCount;     /* number of PosLookupRecord tables */
 477   HB_UShort*            Class;        /* array of classes                 */
 478   HB_PosLookupRecord*  PosLookupRecord;
 479                                       /* array of PosLookupRecord tables  */
 480 };
 481
 482 typedef struct HB_PosClassRule_  HB_PosClassRule;
 483
 484
 485 struct  HB_PosClassSet_
 486 {
 487   HB_UShort          PosClassRuleCount;
 488                                       /* number of PosClassRule tables */
 489   HB_PosClassRule*  PosClassRule;    /* array of PosClassRule tables  */
 490 };
 491
 492 typedef struct HB_PosClassSet_  HB_PosClassSet;
 493
 494
 495 /* The `MaxContextLength' field is not defined in the TTO specification
 496    but simplifies the implementation of this format.  It holds the
 497    maximal context length used in the context rules.                    */
 498
 499 struct  HB_ContextPosFormat2_
 500 {
 501   HB_UShort            MaxContextLength;
 502                                       /* maximal context length       */
 503   HB_Coverage         Coverage;      /* Coverage table               */
 504   HB_ClassDefinition  ClassDef;      /* ClassDef table               */
 505   HB_UShort            PosClassSetCount;
 506                                       /* number of PosClassSet tables */
 507   HB_PosClassSet*     PosClassSet;   /* array of PosClassSet tables  */
 508 };
 509
 510 typedef struct HB_ContextPosFormat2_  HB_ContextPosFormat2;
 511
 512
 513 struct  HB_ContextPosFormat3_
 514 {
 515   HB_UShort             GlyphCount;   /* number of input glyphs           */
 516   HB_UShort             PosCount;     /* number of PosLookupRecord tables */
 517   HB_Coverage*         Coverage;     /* array of Coverage tables         */
 518   HB_PosLookupRecord*  PosLookupRecord;
 519                                       /* array of PosLookupRecord tables  */
 520 };
 521
 522 typedef struct HB_ContextPosFormat3_  HB_ContextPosFormat3;
 523
 524
 525 struct  HB_ContextPos_
 526 {
 527   HB_Byte  PosFormat;                 /* 1, 2, or 3     */
 528
 529   union
 530   {
 531     HB_ContextPosFormat1  cpf1;
 532     HB_ContextPosFormat2  cpf2;
 533     HB_ContextPosFormat3  cpf3;
 534   } cpf;
 535 };
 536
 537 typedef struct HB_ContextPos_  HB_ContextPos;
 538
 539
 540 /* LookupType 8 */
 541
 542 struct  HB_ChainPosRule_
 543 {
 544   HB_UShort*            Backtrack;    /* array of backtrack glyph IDs     */
 545   HB_UShort*            Input;        /* array of input glyph IDs         */
 546   HB_UShort*            Lookahead;    /* array of lookahead glyph IDs     */
 547   HB_PosLookupRecord*  PosLookupRecord;
 548                                       /* array of PosLookupRecords       */
 549   HB_UShort             BacktrackGlyphCount;
 550                                       /* total number of backtrack glyphs */
 551   HB_UShort             InputGlyphCount;
 552                                       /* total number of input glyphs     */
 553   HB_UShort             LookaheadGlyphCount;
 554                                       /* total number of lookahead glyphs */
 555   HB_UShort             PosCount;     /* number of PosLookupRecords       */
 556 };
 557
 558 typedef struct HB_ChainPosRule_  HB_ChainPosRule;
 559
 560
 561 struct  HB_ChainPosRuleSet_
 562 {
 563   HB_UShort          ChainPosRuleCount;
 564                                       /* number of ChainPosRule tables */
 565   HB_ChainPosRule*  ChainPosRule;    /* array of ChainPosRule tables  */
 566 };
 567
 568 typedef struct HB_ChainPosRuleSet_  HB_ChainPosRuleSet;
 569
 570
 571 struct  HB_ChainContextPosFormat1_
 572 {
 573   HB_Coverage          Coverage;     /* Coverage table                   */
 574   HB_UShort             ChainPosRuleSetCount;
 575                                       /* number of ChainPosRuleSet tables */
 576   HB_ChainPosRuleSet*  ChainPosRuleSet;
 577                                       /* array of ChainPosRuleSet tables  */
 578 };
 579
 580 typedef struct HB_ChainContextPosFormat1_  HB_ChainContextPosFormat1;
 581
 582
 583 struct  HB_ChainPosClassRule_
 584 {
 585   HB_UShort*            Backtrack;    /* array of backtrack classes      */
 586   HB_UShort*            Input;        /* array of context classes        */
 587   HB_UShort*            Lookahead;    /* array of lookahead classes      */
 588   HB_PosLookupRecord*  PosLookupRecord;
 589                                       /* array of substitution lookups   */
 590   HB_UShort             BacktrackGlyphCount;
 591                                       /* total number of backtrack
 592                                          classes                         */
 593   HB_UShort             InputGlyphCount;
 594                                       /* total number of context classes */
 595   HB_UShort             LookaheadGlyphCount;
 596                                       /* total number of lookahead
 597                                          classes                         */
 598   HB_UShort             PosCount;     /* number of PosLookupRecords      */
 599 };
 600
 601 typedef struct HB_ChainPosClassRule_  HB_ChainPosClassRule;
 602
 603
 604 struct  HB_ChainPosClassSet_
 605 {
 606   HB_UShort               ChainPosClassRuleCount;
 607                                       /* number of ChainPosClassRule
 608                                          tables                      */
 609   HB_ChainPosClassRule*  ChainPosClassRule;
 610                                       /* array of ChainPosClassRule
 611                                          tables                      */
 612 };
 613
 614 typedef struct HB_ChainPosClassSet_  HB_ChainPosClassSet;
 615
 616
 617 /* The `MaxXXXLength' fields are not defined in the TTO specification
 618    but simplifies the implementation of this format.  It holds the
 619    maximal context length used in the specific context rules.         */
 620
 621 struct  HB_ChainContextPosFormat2_
 622 {
 623   HB_Coverage           Coverage;    /* Coverage table             */
 624
 625   HB_UShort              MaxBacktrackLength;
 626                                       /* maximal backtrack length   */
 627   HB_ClassDefinition    BacktrackClassDef;
 628                                       /* BacktrackClassDef table    */
 629   HB_UShort              MaxInputLength;
 630                                       /* maximal input length       */
 631   HB_ClassDefinition    InputClassDef;
 632                                       /* InputClassDef table        */
 633   HB_UShort              MaxLookaheadLength;
 634                                       /* maximal lookahead length   */
 635   HB_ClassDefinition    LookaheadClassDef;
 636                                       /* LookaheadClassDef table    */
 637
 638   HB_UShort              ChainPosClassSetCount;
 639                                       /* number of ChainPosClassSet
 640                                          tables                     */
 641   HB_ChainPosClassSet*  ChainPosClassSet;
 642                                       /* array of ChainPosClassSet
 643                                          tables                     */
 644 };
 645
 646 typedef struct HB_ChainContextPosFormat2_  HB_ChainContextPosFormat2;
 647
 648
 649 struct  HB_ChainContextPosFormat3_
 650 {
 651   HB_UShort             BacktrackGlyphCount;
 652                                       /* number of backtrack glyphs    */
 653   HB_Coverage*         BacktrackCoverage;
 654                                       /* array of backtrack Coverage
 655                                          tables                        */
 656   HB_UShort             InputGlyphCount;
 657                                       /* number of input glyphs        */
 658   HB_Coverage*         InputCoverage;
 659                                       /* array of input coverage
 660                                          tables                        */
 661   HB_UShort             LookaheadGlyphCount;
 662                                       /* number of lookahead glyphs    */
 663   HB_Coverage*         LookaheadCoverage;
 664                                       /* array of lookahead coverage
 665                                          tables                        */
 666   HB_UShort             PosCount;     /* number of PosLookupRecords    */
 667   HB_PosLookupRecord*  PosLookupRecord;
 668                                       /* array of substitution lookups */
 669 };
 670
 671 typedef struct HB_ChainContextPosFormat3_  HB_ChainContextPosFormat3;
 672
 673
 674 struct  HB_ChainContextPos_
 675 {
 676   HB_Byte  PosFormat;               /* 1, 2, or 3 */
 677
 678   union
 679   {
 680     HB_ChainContextPosFormat1  ccpf1;
 681     HB_ChainContextPosFormat2  ccpf2;
 682     HB_ChainContextPosFormat3  ccpf3;
 683   } ccpf;
 684 };
 685
 686 typedef struct HB_ChainContextPos_  HB_ChainContextPos;
 687
 688
 689 #if 0
 690 /* LookupType 10 */
 691 struct HB_ExtensionPos_
 692 {
 693   HB_UShort      PosFormat;           /* always 1 */
 694   HB_UShort      LookuptType;         /* lookup-type of referenced subtable */
 695   HB_GPOS_SubTable *subtable;         /* referenced subtable */
 696 };
 697
 698 typedef struct HB_ExtensionPos_  HB_ExtensionPos;
 699 #endif
 700
 701
 702 union  HB_GPOS_SubTable_
 703 {
 704   HB_SinglePos        single;
 705   HB_PairPos          pair;
 706   HB_CursivePos       cursive;
 707   HB_MarkBasePos      markbase;
 708   HB_MarkLigPos       marklig;
 709   HB_MarkMarkPos      markmark;
 710   HB_ContextPos       context;
 711   HB_ChainContextPos  chain;
 712 };
 713
 714 typedef union HB_GPOS_SubTable_  HB_GPOS_SubTable;
 715
 716
 717
 718 HB_INTERNAL HB_Error
 719 _HB_GPOS_Load_SubTable( HB_GPOS_SubTable* st,
 720                                   HB_Stream     stream,
 721                                   HB_UShort     lookup_type );
 722
 723 HB_INTERNAL void
 724 _HB_GPOS_Free_SubTable( HB_GPOS_SubTable* st,
 725                               HB_UShort     lookup_type );
 726
 727 HB_END_HEADER
 728
 729 #endif /* HARFBUZZ_GPOS_PRIVATE_H */