third_party/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 #ifdef HB_USE_PACKED_STRUCTS
  36 #pragma pack(push, 1)
  37 #endif
  38
  39 /* shared tables */
  40
  41 #define VR_X_PLACEMENT_DEVICE 0
  42 #define VR_Y_PLACEMENT_DEVICE 1
  43 #define VR_X_ADVANCE_DEVICE   2
  44 #define VR_Y_ADVANCE_DEVICE   3
  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_Class2Record*  Class2Record;    /* array of Class2Record tables */
 250 };
 251
 252 typedef struct HB_Class1Record_  HB_Class1Record;
 253
 254
 255 struct  HB_PairPosFormat2_
 256 {
 257   HB_ClassDefinition  ClassDef1;     /* class def. for first glyph     */
 258   HB_ClassDefinition  ClassDef2;     /* class def. for second glyph    */
 259   HB_UShort            Class1Count;   /* number of classes in ClassDef1
 260                                          table                          */
 261   HB_UShort            Class2Count;   /* number of classes in ClassDef2
 262                                          table                          */
 263   HB_Class1Record*    Class1Record;  /* array of Class1Record tables   */
 264 };
 265
 266 typedef struct HB_PairPosFormat2_  HB_PairPosFormat2;
 267
 268
 269 struct  HB_PairPos_
 270 {
 271   HB_Byte       PosFormat;            /* 1 or 2         */
 272   HB_Coverage  Coverage;             /* Coverage table */
 273   HB_UShort     ValueFormat1;         /* format of ValueRecord table
 274                                          for first glyph             */
 275   HB_UShort     ValueFormat2;         /* format of ValueRecord table
 276                                          for second glyph            */
 277
 278   union
 279   {
 280     HB_PairPosFormat1  ppf1;
 281     HB_PairPosFormat2  ppf2;
 282   } ppf;
 283 };
 284
 285 typedef struct HB_PairPos_  HB_PairPos;
 286
 287
 288 /* LookupType 3 */
 289
 290 struct  HB_EntryExitRecord_
 291 {
 292   HB_Anchor  EntryAnchor;            /* entry Anchor table */
 293   HB_Anchor  ExitAnchor;             /* exit Anchor table  */
 294 };
 295
 296
 297 typedef struct HB_EntryExitRecord_  HB_EntryExitRecord;
 298
 299 struct  HB_CursivePos_
 300 {
 301   HB_UShort             PosFormat;    /* always 1                         */
 302   HB_Coverage          Coverage;     /* Coverage table                   */
 303   HB_UShort             EntryExitCount;
 304                                       /* number of EntryExitRecord tables */
 305   HB_EntryExitRecord*  EntryExitRecord;
 306                                       /* array of EntryExitRecord tables  */
 307 };
 308
 309 typedef struct HB_CursivePos_  HB_CursivePos;
 310
 311
 312 /* LookupType 4 */
 313
 314 struct  HB_BaseRecord_
 315 {
 316   HB_Anchor*  BaseAnchor;            /* array of base glyph anchor
 317                                          tables                     */
 318 };
 319
 320 typedef struct HB_BaseRecord_  HB_BaseRecord;
 321
 322
 323 struct  HB_BaseArray_
 324 {
 325   HB_UShort        BaseCount;         /* number of BaseRecord tables */
 326   HB_BaseRecord*  BaseRecord;        /* array of BaseRecord tables  */
 327 };
 328
 329 typedef struct HB_BaseArray_  HB_BaseArray;
 330
 331
 332 struct  HB_MarkBasePos_
 333 {
 334   HB_UShort      PosFormat;           /* always 1                  */
 335   HB_Coverage   MarkCoverage;        /* mark glyph coverage table */
 336   HB_Coverage   BaseCoverage;        /* base glyph coverage table */
 337   HB_UShort      ClassCount;          /* number of mark classes    */
 338   HB_MarkArray  MarkArray;           /* mark array table          */
 339   HB_BaseArray  BaseArray;           /* base array table          */
 340 };
 341
 342 typedef struct HB_MarkBasePos_  HB_MarkBasePos;
 343
 344
 345 /* LookupType 5 */
 346
 347 struct  HB_ComponentRecord_
 348 {
 349   HB_Anchor*  LigatureAnchor;        /* array of ligature glyph anchor
 350                                          tables                         */
 351 };
 352
 353 typedef struct HB_ComponentRecord_  HB_ComponentRecord;
 354
 355
 356 struct  HB_LigatureAttach_
 357 {
 358   HB_UShort             ComponentCount;
 359                                       /* number of ComponentRecord tables */
 360   HB_ComponentRecord*  ComponentRecord;
 361                                       /* array of ComponentRecord tables  */
 362 };
 363
 364 typedef struct HB_LigatureAttach_  HB_LigatureAttach;
 365
 366
 367 struct  HB_LigatureArray_
 368 {
 369   HB_UShort            LigatureCount; /* number of LigatureAttach tables */
 370   HB_LigatureAttach*  LigatureAttach;
 371                                       /* array of LigatureAttach tables  */
 372 };
 373
 374 typedef struct HB_LigatureArray_  HB_LigatureArray;
 375
 376
 377 struct  HB_MarkLigPos_
 378 {
 379   HB_UShort          PosFormat;       /* always 1                      */
 380   HB_Coverage       MarkCoverage;    /* mark glyph coverage table     */
 381   HB_Coverage       LigatureCoverage;
 382                                       /* ligature glyph coverage table */
 383   HB_UShort          ClassCount;      /* number of mark classes        */
 384   HB_MarkArray      MarkArray;       /* mark array table              */
 385   HB_LigatureArray  LigatureArray;   /* ligature array table          */
 386 };
 387
 388 typedef struct HB_MarkLigPos_  HB_MarkLigPos;
 389
 390
 391 /* LookupType 6 */
 392
 393 struct  HB_Mark2Record_
 394 {
 395   HB_Anchor*  Mark2Anchor;           /* array of mark glyph anchor
 396                                          tables                     */
 397 };
 398
 399 typedef struct HB_Mark2Record_  HB_Mark2Record;
 400
 401
 402 struct  HB_Mark2Array_
 403 {
 404   HB_UShort         Mark2Count;       /* number of Mark2Record tables */
 405   HB_Mark2Record*  Mark2Record;      /* array of Mark2Record tables  */
 406 };
 407
 408 typedef struct HB_Mark2Array_  HB_Mark2Array;
 409
 410
 411 struct  HB_MarkMarkPos_
 412 {
 413   HB_UShort       PosFormat;          /* always 1                         */
 414   HB_Coverage    Mark1Coverage;      /* first mark glyph coverage table  */
 415   HB_Coverage    Mark2Coverage;      /* second mark glyph coverave table */
 416   HB_UShort       ClassCount;         /* number of combining mark classes */
 417   HB_MarkArray   Mark1Array;         /* MarkArray table for first mark   */
 418   HB_Mark2Array  Mark2Array;         /* MarkArray table for second mark  */
 419 };
 420
 421 typedef struct HB_MarkMarkPos_  HB_MarkMarkPos;
 422
 423
 424 /* needed by both lookup type 7 and 8 */
 425
 426 struct  HB_PosLookupRecord_
 427 {
 428   HB_UShort  SequenceIndex;           /* index into current
 429                                          glyph sequence               */
 430   HB_UShort  LookupListIndex;         /* Lookup to apply to that pos. */
 431 };
 432
 433 typedef struct HB_PosLookupRecord_  HB_PosLookupRecord;
 434
 435
 436 /* LookupType 7 */
 437
 438 struct  HB_PosRule_
 439 {
 440   HB_UShort             GlyphCount;   /* total number of input glyphs     */
 441   HB_UShort             PosCount;     /* number of PosLookupRecord tables */
 442   HB_UShort*            Input;        /* array of input glyph IDs         */
 443   HB_PosLookupRecord*  PosLookupRecord;
 444                                       /* array of PosLookupRecord tables  */
 445 };
 446
 447 typedef struct HB_PosRule_  HB_PosRule;
 448
 449
 450 struct  HB_PosRuleSet_
 451 {
 452   HB_UShort     PosRuleCount;         /* number of PosRule tables */
 453   HB_PosRule*  PosRule;              /* array of PosRule tables  */
 454 };
 455
 456 typedef struct HB_PosRuleSet_  HB_PosRuleSet;
 457
 458
 459 struct  HB_ContextPosFormat1_
 460 {
 461   HB_Coverage     Coverage;          /* Coverage table              */
 462   HB_UShort        PosRuleSetCount;   /* number of PosRuleSet tables */
 463   HB_PosRuleSet*  PosRuleSet;        /* array of PosRuleSet tables  */
 464 };
 465
 466 typedef struct HB_ContextPosFormat1_  HB_ContextPosFormat1;
 467
 468
 469 struct  HB_PosClassRule_
 470 {
 471   HB_UShort             GlyphCount;   /* total number of context classes  */
 472   HB_UShort             PosCount;     /* number of PosLookupRecord tables */
 473   HB_UShort*            Class;        /* array of classes                 */
 474   HB_PosLookupRecord*  PosLookupRecord;
 475                                       /* array of PosLookupRecord tables  */
 476 };
 477
 478 typedef struct HB_PosClassRule_  HB_PosClassRule;
 479
 480
 481 struct  HB_PosClassSet_
 482 {
 483   HB_UShort          PosClassRuleCount;
 484                                       /* number of PosClassRule tables */
 485   HB_PosClassRule*  PosClassRule;    /* array of PosClassRule tables  */
 486 };
 487
 488 typedef struct HB_PosClassSet_  HB_PosClassSet;
 489
 490
 491 /* The `MaxContextLength' field is not defined in the TTO specification
 492    but simplifies the implementation of this format.  It holds the
 493    maximal context length used in the context rules.                    */
 494
 495 struct  HB_ContextPosFormat2_
 496 {
 497   HB_UShort            MaxContextLength;
 498                                       /* maximal context length       */
 499   HB_Coverage         Coverage;      /* Coverage table               */
 500   HB_ClassDefinition  ClassDef;      /* ClassDef table               */
 501   HB_UShort            PosClassSetCount;
 502                                       /* number of PosClassSet tables */
 503   HB_PosClassSet*     PosClassSet;   /* array of PosClassSet tables  */
 504 };
 505
 506 typedef struct HB_ContextPosFormat2_  HB_ContextPosFormat2;
 507
 508
 509 struct  HB_ContextPosFormat3_
 510 {
 511   HB_UShort             GlyphCount;   /* number of input glyphs           */
 512   HB_UShort             PosCount;     /* number of PosLookupRecord tables */
 513   HB_Coverage*         Coverage;     /* array of Coverage tables         */
 514   HB_PosLookupRecord*  PosLookupRecord;
 515                                       /* array of PosLookupRecord tables  */
 516 };
 517
 518 typedef struct HB_ContextPosFormat3_  HB_ContextPosFormat3;
 519
 520
 521 struct  HB_ContextPos_
 522 {
 523   HB_Byte  PosFormat;                 /* 1, 2, or 3     */
 524
 525   union
 526   {
 527     HB_ContextPosFormat1  cpf1;
 528     HB_ContextPosFormat2  cpf2;
 529     HB_ContextPosFormat3  cpf3;
 530   } cpf;
 531 };
 532
 533 typedef struct HB_ContextPos_  HB_ContextPos;
 534
 535
 536 /* LookupType 8 */
 537
 538 struct  HB_ChainPosRule_
 539 {
 540   HB_UShort*            Backtrack;    /* array of backtrack glyph IDs     */
 541   HB_UShort*            Input;        /* array of input glyph IDs         */
 542   HB_UShort*            Lookahead;    /* array of lookahead glyph IDs     */
 543   HB_PosLookupRecord*  PosLookupRecord;
 544                                       /* array of PosLookupRecords       */
 545   HB_UShort             BacktrackGlyphCount;
 546                                       /* total number of backtrack glyphs */
 547   HB_UShort             InputGlyphCount;
 548                                       /* total number of input glyphs     */
 549   HB_UShort             LookaheadGlyphCount;
 550                                       /* total number of lookahead glyphs */
 551   HB_UShort             PosCount;     /* number of PosLookupRecords       */
 552 };
 553
 554 typedef struct HB_ChainPosRule_  HB_ChainPosRule;
 555
 556
 557 struct  HB_ChainPosRuleSet_
 558 {
 559   HB_UShort          ChainPosRuleCount;
 560                                       /* number of ChainPosRule tables */
 561   HB_ChainPosRule*  ChainPosRule;    /* array of ChainPosRule tables  */
 562 };
 563
 564 typedef struct HB_ChainPosRuleSet_  HB_ChainPosRuleSet;
 565
 566
 567 struct  HB_ChainContextPosFormat1_
 568 {
 569   HB_Coverage          Coverage;     /* Coverage table                   */
 570   HB_UShort             ChainPosRuleSetCount;
 571                                       /* number of ChainPosRuleSet tables */
 572   HB_ChainPosRuleSet*  ChainPosRuleSet;
 573                                       /* array of ChainPosRuleSet tables  */
 574 };
 575
 576 typedef struct HB_ChainContextPosFormat1_  HB_ChainContextPosFormat1;
 577
 578
 579 struct  HB_ChainPosClassRule_
 580 {
 581   HB_UShort*            Backtrack;    /* array of backtrack classes      */
 582   HB_UShort*            Input;        /* array of context classes        */
 583   HB_UShort*            Lookahead;    /* array of lookahead classes      */
 584   HB_PosLookupRecord*  PosLookupRecord;
 585                                       /* array of substitution lookups   */
 586   HB_UShort             BacktrackGlyphCount;
 587                                       /* total number of backtrack
 588                                          classes                         */
 589   HB_UShort             InputGlyphCount;
 590                                       /* total number of context classes */
 591   HB_UShort             LookaheadGlyphCount;
 592                                       /* total number of lookahead
 593                                          classes                         */
 594   HB_UShort             PosCount;     /* number of PosLookupRecords      */
 595 };
 596
 597 typedef struct HB_ChainPosClassRule_  HB_ChainPosClassRule;
 598
 599
 600 struct  HB_ChainPosClassSet_
 601 {
 602   HB_UShort               ChainPosClassRuleCount;
 603                                       /* number of ChainPosClassRule
 604                                          tables                      */
 605   HB_ChainPosClassRule*  ChainPosClassRule;
 606                                       /* array of ChainPosClassRule
 607                                          tables                      */
 608 };
 609
 610 typedef struct HB_ChainPosClassSet_  HB_ChainPosClassSet;
 611
 612
 613 /* The `MaxXXXLength' fields are not defined in the TTO specification
 614    but simplifies the implementation of this format.  It holds the
 615    maximal context length used in the specific context rules.         */
 616
 617 struct  HB_ChainContextPosFormat2_
 618 {
 619   HB_Coverage           Coverage;    /* Coverage table             */
 620
 621   HB_UShort              MaxBacktrackLength;
 622                                       /* maximal backtrack length   */
 623   HB_ClassDefinition    BacktrackClassDef;
 624                                       /* BacktrackClassDef table    */
 625   HB_UShort              MaxInputLength;
 626                                       /* maximal input length       */
 627   HB_ClassDefinition    InputClassDef;
 628                                       /* InputClassDef table        */
 629   HB_UShort              MaxLookaheadLength;
 630                                       /* maximal lookahead length   */
 631   HB_ClassDefinition    LookaheadClassDef;
 632                                       /* LookaheadClassDef table    */
 633
 634   HB_UShort              ChainPosClassSetCount;
 635                                       /* number of ChainPosClassSet
 636                                          tables                     */
 637   HB_ChainPosClassSet*  ChainPosClassSet;
 638                                       /* array of ChainPosClassSet
 639                                          tables                     */
 640 };
 641
 642 typedef struct HB_ChainContextPosFormat2_  HB_ChainContextPosFormat2;
 643
 644
 645 struct  HB_ChainContextPosFormat3_
 646 {
 647   HB_UShort             BacktrackGlyphCount;
 648                                       /* number of backtrack glyphs    */
 649   HB_Coverage*         BacktrackCoverage;
 650                                       /* array of backtrack Coverage
 651                                          tables                        */
 652   HB_UShort             InputGlyphCount;
 653                                       /* number of input glyphs        */
 654   HB_Coverage*         InputCoverage;
 655                                       /* array of input coverage
 656                                          tables                        */
 657   HB_UShort             LookaheadGlyphCount;
 658                                       /* number of lookahead glyphs    */
 659   HB_Coverage*         LookaheadCoverage;
 660                                       /* array of lookahead coverage
 661                                          tables                        */
 662   HB_UShort             PosCount;     /* number of PosLookupRecords    */
 663   HB_PosLookupRecord*  PosLookupRecord;
 664                                       /* array of substitution lookups */
 665 };
 666
 667 typedef struct HB_ChainContextPosFormat3_  HB_ChainContextPosFormat3;
 668
 669
 670 struct  HB_ChainContextPos_
 671 {
 672   HB_Byte  PosFormat;               /* 1, 2, or 3 */
 673
 674   union
 675   {
 676     HB_ChainContextPosFormat1  ccpf1;
 677     HB_ChainContextPosFormat2  ccpf2;
 678     HB_ChainContextPosFormat3  ccpf3;
 679   } ccpf;
 680 };
 681
 682 typedef struct HB_ChainContextPos_  HB_ChainContextPos;
 683
 684
 685 #if 0
 686 /* LookupType 10 */
 687 struct HB_ExtensionPos_
 688 {
 689   HB_UShort      PosFormat;           /* always 1 */
 690   HB_UShort      LookuptType;         /* lookup-type of referenced subtable */
 691   HB_GPOS_SubTable *subtable;         /* referenced subtable */
 692 };
 693
 694 typedef struct HB_ExtensionPos_  HB_ExtensionPos;
 695 #endif
 696
 697
 698 union  HB_GPOS_SubTable_
 699 {
 700   HB_SinglePos        single;
 701   HB_PairPos          pair;
 702   HB_CursivePos       cursive;
 703   HB_MarkBasePos      markbase;
 704   HB_MarkLigPos       marklig;
 705   HB_MarkMarkPos      markmark;
 706   HB_ContextPos       context;
 707   HB_ChainContextPos  chain;
 708 };
 709
 710 typedef union HB_GPOS_SubTable_  HB_GPOS_SubTable;
 711
 712
 713
 714 HB_INTERNAL HB_Error
 715 _HB_GPOS_Load_SubTable( HB_GPOS_SubTable* st,
 716                                   HB_Stream     stream,
 717                                   HB_UShort     lookup_type );
 718
 719 HB_INTERNAL void
 720 _HB_GPOS_Free_SubTable( HB_GPOS_SubTable* st,
 721                               HB_UShort     lookup_type );
 722
 723 #ifdef HB_USE_PACKED_STRUCTS
 724 #pragma pack(pop)
 725 #endif
 726
 727 HB_END_HEADER
 728
 729 #endif /* HARFBUZZ_GPOS_PRIVATE_H */