third_party/harfbuzz/src/harfbuzz-indic.cpp

   1 /*
   2  * Copyright (C) 2008 Nokia Corporation and/or its subsidiary(-ies)
   3  *
   4  * This is part of HarfBuzz, an OpenType Layout engine library.
   5  *
   6  * Permission is hereby granted, without written agreement and without
   7  * license or royalty fees, to use, copy, modify, and distribute this
   8  * software and its documentation for any purpose, provided that the
   9  * above copyright notice and the following two paragraphs appear in
  10  * all copies of this software.
  11  *
  12  * IN NO EVENT SHALL THE COPYRIGHT HOLDER BE LIABLE TO ANY PARTY FOR
  13  * DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES
  14  * ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN
  15  * IF THE COPYRIGHT HOLDER HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH
  16  * DAMAGE.
  17  *
  18  * THE COPYRIGHT HOLDER SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING,
  19  * BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
  20  * FITNESS FOR A PARTICULAR PURPOSE.  THE SOFTWARE PROVIDED HEREUNDER IS
  21  * ON AN "AS IS" BASIS, AND THE COPYRIGHT HOLDER HAS NO OBLIGATION TO
  22  * PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.
  23  */
  24
  25 #include "harfbuzz-shaper.h"
  26 #include "harfbuzz-shaper-private.h"
  27
  28 #include <assert.h>
  29 #include <stdio.h>
  30
  31 #define FLAG(x) (1 << (x))
  32
  33 static HB_Bool isLetter(HB_UChar16 ucs)
  34 {
  35     const int test = FLAG(HB_Letter_Uppercase) |
  36                      FLAG(HB_Letter_Lowercase) |
  37                      FLAG(HB_Letter_Titlecase) |
  38                      FLAG(HB_Letter_Modifier) |
  39                      FLAG(HB_Letter_Other);
  40     return !!(FLAG(HB_GetUnicodeCharCategory(ucs)) & test);
  41 }
  42
  43 static HB_Bool isMark(HB_UChar16 ucs)
  44 {
  45     const int test = FLAG(HB_Mark_NonSpacing) |
  46                      FLAG(HB_Mark_SpacingCombining) |
  47                      FLAG(HB_Mark_Enclosing);
  48     return !!(FLAG(HB_GetUnicodeCharCategory(ucs)) & test);
  49 }
  50
  51 enum Form {
  52     Invalid = 0x0,
  53     UnknownForm = Invalid,
  54     Consonant,
  55     Nukta,
  56     Halant,
  57     Matra,
  58     VowelMark,
  59     StressMark,
  60     IndependentVowel,
  61     LengthMark,
  62     Control,
  63     Other
  64 };
  65
  66 static const unsigned char indicForms[0xe00-0x900] = {
  67     // Devangari
  68     Invalid, VowelMark, VowelMark, VowelMark,
  69     IndependentVowel, IndependentVowel, IndependentVowel, IndependentVowel,
  70     IndependentVowel, IndependentVowel, IndependentVowel, IndependentVowel,
  71     IndependentVowel, IndependentVowel, IndependentVowel, IndependentVowel,
  72
  73     IndependentVowel, IndependentVowel, IndependentVowel, IndependentVowel,
  74     IndependentVowel, Consonant, Consonant, Consonant,
  75     Consonant, Consonant, Consonant, Consonant,
  76     Consonant, Consonant, Consonant, Consonant,
  77
  78     Consonant, Consonant, Consonant, Consonant,
  79     Consonant, Consonant, Consonant, Consonant,
  80     Consonant, Consonant, Consonant, Consonant,
  81     Consonant, Consonant, Consonant, Consonant,
  82
  83     Consonant, Consonant, Consonant, Consonant,
  84     Consonant, Consonant, Consonant, Consonant,
  85     Consonant, Consonant, UnknownForm, UnknownForm,
  86     Nukta, Other, Matra, Matra,
  87
  88     Matra, Matra, Matra, Matra,
  89     Matra, Matra, Matra, Matra,
  90     Matra, Matra, Matra, Matra,
  91     Matra, Halant, UnknownForm, UnknownForm,
  92
  93     Other, StressMark, StressMark, StressMark,
  94     StressMark, UnknownForm, UnknownForm, UnknownForm,
  95     Consonant, Consonant, Consonant, Consonant,
  96     Consonant, Consonant, Consonant, Consonant,
  97
  98     IndependentVowel, IndependentVowel, VowelMark, VowelMark,
  99     Other, Other, Other, Other,
 100     Other, Other, Other, Other,
 101     Other, Other, Other, Other,
 102
 103     Other, Other, Other, Other,
 104     Other, Other, Other, Other,
 105     Other, Other, Other, Consonant,
 106     Consonant, Consonant /* ??? */, Consonant, Consonant,
 107
 108     // Bengali
 109     Invalid, VowelMark, VowelMark, VowelMark,
 110     Invalid, IndependentVowel, IndependentVowel, IndependentVowel,
 111     IndependentVowel, IndependentVowel, IndependentVowel, IndependentVowel,
 112     IndependentVowel, Invalid, Invalid, IndependentVowel,
 113
 114     IndependentVowel, Invalid, Invalid, IndependentVowel,
 115     IndependentVowel, Consonant, Consonant, Consonant,
 116     Consonant, Consonant, Consonant, Consonant,
 117     Consonant, Consonant, Consonant, Consonant,
 118
 119     Consonant, Consonant, Consonant, Consonant,
 120     Consonant, Consonant, Consonant, Consonant,
 121     Consonant, Invalid, Consonant, Consonant,
 122     Consonant, Consonant, Consonant, Consonant,
 123
 124     Consonant, Invalid, Consonant, Invalid,
 125     Invalid, Invalid, Consonant, Consonant,
 126     Consonant, Consonant, UnknownForm, UnknownForm,
 127     Nukta, Other, Matra, Matra,
 128
 129     Matra, Matra, Matra, Matra,
 130     Matra, Invalid, Invalid, Matra,
 131     Matra, Invalid, Invalid, Matra,
 132     Matra, Halant, Consonant, UnknownForm,
 133
 134     Invalid, Invalid, Invalid, Invalid,
 135     Invalid, Invalid, Invalid, VowelMark,
 136     Invalid, Invalid, Invalid, Invalid,
 137     Consonant, Consonant, Invalid, Consonant,
 138
 139     IndependentVowel, IndependentVowel, VowelMark, VowelMark,
 140     Other, Other, Other, Other,
 141     Other, Other, Other, Other,
 142     Other, Other, Other, Other,
 143
 144     Consonant, Consonant, Other, Other,
 145     Other, Other, Other, Other,
 146     Other, Other, Other, Other,
 147     Other, Other, Other, Other,
 148
 149     // Gurmukhi
 150     Invalid, VowelMark, VowelMark, VowelMark,
 151     Invalid, IndependentVowel, IndependentVowel, IndependentVowel,
 152     IndependentVowel, IndependentVowel, IndependentVowel, Invalid,
 153     Invalid, Invalid, Invalid, IndependentVowel,
 154
 155     IndependentVowel, Invalid, Invalid, IndependentVowel,
 156     IndependentVowel, Consonant, Consonant, Consonant,
 157     Consonant, Consonant, Consonant, Consonant,
 158     Consonant, Consonant, Consonant, Consonant,
 159
 160     Consonant, Consonant, Consonant, Consonant,
 161     Consonant, Consonant, Consonant, Consonant,
 162     Consonant, Invalid, Consonant, Consonant,
 163     Consonant, Consonant, Consonant, Consonant,
 164
 165     Consonant, Invalid, Consonant, Consonant,
 166     Invalid, Consonant, Consonant, Invalid,
 167     Consonant, Consonant, UnknownForm, UnknownForm,
 168     Nukta, Other, Matra, Matra,
 169
 170     Matra, Matra, Matra, Invalid,
 171     Invalid, Invalid, Invalid, Matra,
 172     Matra, Invalid, Invalid, Matra,
 173     Matra, Halant, UnknownForm, UnknownForm,
 174
 175     Invalid, Invalid, Invalid, Invalid,
 176     Invalid, UnknownForm, UnknownForm, UnknownForm,
 177     Invalid, Consonant, Consonant, Consonant,
 178     Consonant, Invalid, Consonant, Invalid,
 179
 180     Other, Other, Invalid, Invalid,
 181     Other, Other, Other, Other,
 182     Other, Other, Other, Other,
 183     Other, Other, Other, Other,
 184
 185     StressMark, StressMark, Consonant, Consonant,
 186     Other, Other, Other, Other,
 187     Other, Other, Other, Other,
 188     Other, Other, Other, Other,
 189
 190     // Gujarati
 191     Invalid, VowelMark, VowelMark, VowelMark,
 192     Invalid, IndependentVowel, IndependentVowel, IndependentVowel,
 193     IndependentVowel, IndependentVowel, IndependentVowel, IndependentVowel,
 194     IndependentVowel, IndependentVowel, Invalid, IndependentVowel,
 195
 196     IndependentVowel, IndependentVowel, Invalid, IndependentVowel,
 197     IndependentVowel, Consonant, Consonant, Consonant,
 198     Consonant, Consonant, Consonant, Consonant,
 199     Consonant, Consonant, Consonant, Consonant,
 200
 201     Consonant, Consonant, Consonant, Consonant,
 202     Consonant, Consonant, Consonant, Consonant,
 203     Consonant, Invalid, Consonant, Consonant,
 204     Consonant, Consonant, Consonant, Consonant,
 205
 206     Consonant, Invalid, Consonant, Consonant,
 207     Invalid, Consonant, Consonant, Consonant,
 208     Consonant, Consonant, UnknownForm, UnknownForm,
 209     Nukta, Other, Matra, Matra,
 210
 211     Matra, Matra, Matra, Matra,
 212     Matra, Matra, Invalid, Matra,
 213     Matra, Matra, Invalid, Matra,
 214     Matra, Halant, UnknownForm, UnknownForm,
 215
 216     Other, UnknownForm, UnknownForm, UnknownForm,
 217     UnknownForm, UnknownForm, UnknownForm, UnknownForm,
 218     UnknownForm, UnknownForm, UnknownForm, UnknownForm,
 219     UnknownForm, UnknownForm, UnknownForm, UnknownForm,
 220
 221     IndependentVowel, IndependentVowel, VowelMark, VowelMark,
 222     Other, Other, Other, Other,
 223     Other, Other, Other, Other,
 224     Other, Other, Other, Other,
 225
 226     Other, Other, Other, Other,
 227     Other, Other, Other, Other,
 228     Other, Other, Other, Other,
 229     Other, Other, Other, Other,
 230
 231     // Oriya
 232     Invalid, VowelMark, VowelMark, VowelMark,
 233     Invalid, IndependentVowel, IndependentVowel, IndependentVowel,
 234     IndependentVowel, IndependentVowel, IndependentVowel, IndependentVowel,
 235     IndependentVowel, Invalid, Invalid, IndependentVowel,
 236
 237     IndependentVowel, Invalid, Invalid, IndependentVowel,
 238     IndependentVowel, Consonant, Consonant, Consonant,
 239     Consonant, Consonant, Consonant, Consonant,
 240     Consonant, Consonant, Consonant, Consonant,
 241
 242     Consonant, Consonant, Consonant, Consonant,
 243     Consonant, Consonant, Consonant, Consonant,
 244     Consonant, Invalid, Consonant, Consonant,
 245     Consonant, Consonant, Consonant, Consonant,
 246
 247     Consonant, Invalid, Consonant, Consonant,
 248     Invalid, Consonant, Consonant, Consonant,
 249     Consonant, Consonant, UnknownForm, UnknownForm,
 250     Nukta, Other, Matra, Matra,
 251
 252     Matra, Matra, Matra, Matra,
 253     Invalid, Invalid, Invalid, Matra,
 254     Matra, Invalid, Invalid, Matra,
 255     Matra, Halant, UnknownForm, UnknownForm,
 256
 257     Other, Invalid, Invalid, Invalid,
 258     Invalid, UnknownForm, LengthMark, LengthMark,
 259     Invalid, Invalid, Invalid, Invalid,
 260     Consonant, Consonant, Invalid, Consonant,
 261
 262     IndependentVowel, IndependentVowel, Invalid, Invalid,
 263     Invalid, Invalid, Other, Other,
 264     Other, Other, Other, Other,
 265     Other, Other, Other, Other,
 266
 267     Other, Consonant, Other, Other,
 268     Other, Other, Other, Other,
 269     Other, Other, Other, Other,
 270     Other, Other, Other, Other,
 271
 272     //Tamil
 273     Invalid, Invalid, VowelMark, Other,
 274     Invalid, IndependentVowel, IndependentVowel, IndependentVowel,
 275     IndependentVowel, IndependentVowel, IndependentVowel, Invalid,
 276     Invalid, Invalid, IndependentVowel, IndependentVowel,
 277
 278     IndependentVowel, Invalid, IndependentVowel, IndependentVowel,
 279     IndependentVowel, Consonant, Invalid, Invalid,
 280     Invalid, Consonant, Consonant, Invalid,
 281     Consonant, Invalid, Consonant, Consonant,
 282
 283     Invalid, Invalid, Invalid, Consonant,
 284     Consonant, Invalid, Invalid, Invalid,
 285     Consonant, Consonant, Consonant, Invalid,
 286     Invalid, Invalid, Consonant, Consonant,
 287
 288     Consonant, Consonant, Consonant, Consonant,
 289     Consonant, Consonant, Consonant, Consonant,
 290     Consonant, Consonant, UnknownForm, UnknownForm,
 291     Invalid, Invalid, Matra, Matra,
 292
 293     Matra, Matra, Matra, Invalid,
 294     Invalid, Invalid, Matra, Matra,
 295     Matra, Invalid, Matra, Matra,
 296     Matra, Halant, Invalid, Invalid,
 297
 298     Invalid, Invalid, Invalid, Invalid,
 299     Invalid, Invalid, Invalid, LengthMark,
 300     Invalid, Invalid, Invalid, Invalid,
 301     Invalid, Invalid, Invalid, Invalid,
 302
 303     Invalid, Invalid, Invalid, Invalid,
 304     Invalid, Invalid, Other, Other,
 305     Other, Other, Other, Other,
 306     Other, Other, Other, Other,
 307
 308     Other, Other, Other, Other,
 309     Other, Other, Other, Other,
 310     Other, Other, Other, Other,
 311     Other, Other, Other, Other,
 312
 313     // Telugu
 314     Invalid, VowelMark, VowelMark, VowelMark,
 315     Invalid, IndependentVowel, IndependentVowel, IndependentVowel,
 316     IndependentVowel, IndependentVowel, IndependentVowel, IndependentVowel,
 317     IndependentVowel, Invalid, IndependentVowel, IndependentVowel,
 318
 319     IndependentVowel, Invalid, IndependentVowel, IndependentVowel,
 320     IndependentVowel, Consonant, Consonant, Consonant,
 321     Consonant, Consonant, Consonant, Consonant,
 322     Consonant, Consonant, Consonant, Consonant,
 323
 324     Consonant, Consonant, Consonant, Consonant,
 325     Consonant, Consonant, Consonant, Consonant,
 326     Consonant, Invalid, Consonant, Consonant,
 327     Consonant, Consonant, Consonant, Consonant,
 328
 329     Consonant, Consonant, Consonant, Consonant,
 330     Invalid, Consonant, Consonant, Consonant,
 331     Consonant, Consonant, UnknownForm, UnknownForm,
 332     Invalid, Invalid, Matra, Matra,
 333
 334     Matra, Matra, Matra, Matra,
 335     Matra, Invalid, Matra, Matra,
 336     Matra, Invalid, Matra, Matra,
 337     Matra, Halant, Invalid, Invalid,
 338
 339     Invalid, Invalid, Invalid, Invalid,
 340     Invalid, LengthMark, Matra, Invalid,
 341     Invalid, Invalid, Invalid, Invalid,
 342     Invalid, Invalid, Invalid, Invalid,
 343
 344     IndependentVowel, IndependentVowel, Invalid, Invalid,
 345     Invalid, Invalid, Other, Other,
 346     Other, Other, Other, Other,
 347     Other, Other, Other, Other,
 348
 349     Other, Other, Other, Other,
 350     Other, Other, Other, Other,
 351     Other, Other, Other, Other,
 352     Other, Other, Other, Other,
 353
 354     // Kannada
 355     Invalid, Invalid, VowelMark, VowelMark,
 356     Invalid, IndependentVowel, IndependentVowel, IndependentVowel,
 357     IndependentVowel, IndependentVowel, IndependentVowel, IndependentVowel,
 358     IndependentVowel, Invalid, IndependentVowel, IndependentVowel,
 359
 360     IndependentVowel, Invalid, IndependentVowel, IndependentVowel,
 361     IndependentVowel, Consonant, Consonant, Consonant,
 362     Consonant, Consonant, Consonant, Consonant,
 363     Consonant, Consonant, Consonant, Consonant,
 364
 365     Consonant, Consonant, Consonant, Consonant,
 366     Consonant, Consonant, Consonant, Consonant,
 367     Consonant, Invalid, Consonant, Consonant,
 368     Consonant, Consonant, Consonant, Consonant,
 369
 370     Consonant, Consonant, Consonant, Consonant,
 371     Invalid, Consonant, Consonant, Consonant,
 372     Consonant, Consonant, UnknownForm, UnknownForm,
 373     Nukta, Other, Matra, Matra,
 374
 375     Matra, Matra, Matra, Matra,
 376     Matra, Invalid, Matra, Matra,
 377     Matra, Invalid, Matra, Matra,
 378     Matra, Halant, Invalid, Invalid,
 379
 380     Invalid, Invalid, Invalid, Invalid,
 381     Invalid, LengthMark, LengthMark, Invalid,
 382     Invalid, Invalid, Invalid, Invalid,
 383     Invalid, Invalid, Consonant, Invalid,
 384
 385     IndependentVowel, IndependentVowel, VowelMark, VowelMark,
 386     Invalid, Invalid, Other, Other,
 387     Other, Other, Other, Other,
 388     Other, Other, Other, Other,
 389
 390     Other, Other, Other, Other,
 391     Other, Other, Other, Other,
 392     Other, Other, Other, Other,
 393     Other, Other, Other, Other,
 394
 395     // Malayalam
 396     Invalid, Invalid, VowelMark, VowelMark,
 397     Invalid, IndependentVowel, IndependentVowel, IndependentVowel,
 398     IndependentVowel, IndependentVowel, IndependentVowel, IndependentVowel,
 399     IndependentVowel, Invalid, IndependentVowel, IndependentVowel,
 400
 401     IndependentVowel, Invalid, IndependentVowel, IndependentVowel,
 402     IndependentVowel, Consonant, Consonant, Consonant,
 403     Consonant, Consonant, Consonant, Consonant,
 404     Consonant, Consonant, Consonant, Consonant,
 405
 406     Consonant, Consonant, Consonant, Consonant,
 407     Consonant, Consonant, Consonant, Consonant,
 408     Consonant, Invalid, Consonant, Consonant,
 409     Consonant, Consonant, Consonant, Consonant,
 410
 411     Consonant, Consonant, Consonant, Consonant,
 412     Consonant, Consonant, Consonant, Consonant,
 413     Consonant, Consonant, UnknownForm, UnknownForm,
 414     Invalid, Invalid, Matra, Matra,
 415
 416     Matra, Matra, Matra, Matra,
 417     Invalid, Invalid, Matra, Matra,
 418     Matra, Invalid, Matra, Matra,
 419     Matra, Halant, Invalid, Invalid,
 420
 421     Invalid, Invalid, Invalid, Invalid,
 422     Invalid, Invalid, Invalid, Matra,
 423     Invalid, Invalid, Invalid, Invalid,
 424     Invalid, Invalid, Invalid, Invalid,
 425
 426     IndependentVowel, IndependentVowel, Invalid, Invalid,
 427     Invalid, Invalid, Other, Other,
 428     Other, Other, Other, Other,
 429     Other, Other, Other, Other,
 430
 431     Other, Other, Other, Other,
 432     Other, Other, Other, Other,
 433     Other, Other, Other, Other,
 434     Other, Other, Other, Other,
 435
 436     // Sinhala
 437     Invalid, Invalid, VowelMark, VowelMark,
 438     Invalid, IndependentVowel, IndependentVowel, IndependentVowel,
 439     IndependentVowel, IndependentVowel, IndependentVowel, IndependentVowel,
 440     IndependentVowel, IndependentVowel, IndependentVowel, IndependentVowel,
 441
 442     IndependentVowel, IndependentVowel, IndependentVowel, IndependentVowel,
 443     IndependentVowel, IndependentVowel, IndependentVowel, Invalid,
 444     Invalid, Invalid, Consonant, Consonant,
 445     Consonant, Consonant, Consonant, Consonant,
 446
 447     Consonant, Consonant, Consonant, Consonant,
 448     Consonant, Consonant, Consonant, Consonant,
 449     Consonant, Consonant, Consonant, Consonant,
 450     Consonant, Consonant, Consonant, Consonant,
 451
 452     Consonant, Consonant, Invalid, Consonant,
 453     Consonant, Consonant, Consonant, Consonant,
 454     Consonant, Consonant, Consonant, Consonant,
 455     Invalid, Consonant, Invalid, Invalid,
 456
 457     Consonant, Consonant, Consonant, Consonant,
 458     Consonant, Consonant, Consonant, Invalid,
 459     Invalid, Invalid, Halant, Invalid,
 460     Invalid, Invalid, Invalid, Matra,
 461
 462     Matra, Matra, Matra, Matra,
 463     Matra, Invalid, Matra, Invalid,
 464     Matra, Matra, Matra, Matra,
 465     Matra, Matra, Matra, Matra,
 466
 467     Invalid, Invalid, Invalid, Invalid,
 468     Invalid, Invalid, Invalid, Invalid,
 469     Invalid, Invalid, Invalid, Invalid,
 470     Invalid, Invalid, Invalid, Invalid,
 471
 472     Invalid, Invalid, Matra, Matra,
 473     Other, Other, Other, Other,
 474     Other, Other, Other, Other,
 475     Other, Other, Other, Other,
 476 };
 477
 478 enum Position {
 479     None,
 480     Pre,
 481     Above,
 482     Below,
 483     Post,
 484     Split,
 485     Base,
 486     Reph,
 487     Vattu,
 488     Inherit
 489 };
 490
 491 static const unsigned char indicPosition[0xe00-0x900] = {
 492     // Devanagari
 493     None, Above, Above, Post,
 494     None, None, None, None,
 495     None, None, None, None,
 496     None, None, None, None,
 497
 498     None, None, None, None,
 499     None, None, None, None,
 500     None, None, None, None,
 501     None, None, None, None,
 502
 503     None, None, None, None,
 504     None, None, None, None,
 505     None, None, None, None,
 506     None, None, None, None,
 507
 508     Below, None, None, None,
 509     None, None, None, None,
 510     None, None, None, None,
 511     None, None, Post, Pre,
 512
 513     Post, Below, Below, Below,
 514     Below, Above, Above, Above,
 515     Above, Post, Post, Post,
 516     Post, None, None, None,
 517
 518     None, Above, Below, Above,
 519     Above, None, None, None,
 520     None, None, None, None,
 521     None, None, None, None,
 522
 523     None, None, Below, Below,
 524     None, None, None, None,
 525     None, None, None, None,
 526     None, None, None, None,
 527
 528     None, None, None, None,
 529     None, None, None, None,
 530     None, None, None, None,
 531     None, None, None, None,
 532
 533     // Bengali
 534     None, Above, Post, Post,
 535     None, None, None, None,
 536     None, None, None, None,
 537     None, None, None, None,
 538
 539     None, None, None, None,
 540     None, None, None, None,
 541     None, None, None, None,
 542     None, None, None, None,
 543
 544     None, None, None, None,
 545     None, None, None, None,
 546     None, None, None, None,
 547     Below, None, None, Post,
 548
 549     Below, None, None, None,
 550     None, None, None, None,
 551     None, None, None, None,
 552     Below, None, Post, Pre,
 553
 554     Post, Below, Below, Below,
 555     Below, None, None, Pre,
 556     Pre, None, None, Split,
 557     Split, Below, None, None,
 558
 559     None, None, None, None,
 560     None, None, None, Post,
 561     None, None, None, None,
 562     None, None, None, None,
 563
 564     None, None, Below, Below,
 565     None, None, None, None,
 566     None, None, None, None,
 567     None, None, None, None,
 568
 569     Below, None, None, None,
 570     None, None, None, None,
 571     None, None, None, None,
 572     None, None, None, None,
 573
 574     // Gurmukhi
 575     None, Above, Above, Post,
 576     None, None, None, None,
 577     None, None, None, None,
 578     None, None, None, None,
 579
 580     None, None, None, None,
 581     None, None, None, None,
 582     None, None, None, None,
 583     None, None, None, None,
 584
 585     None, None, None, None,
 586     None, None, None, None,
 587     None, None, None, None,
 588     None, None, None, Post,
 589
 590     Below, None, None, None,
 591     None, Below, None, None,
 592     None, Below, None, None,
 593     Below, None, Post, Pre,
 594
 595     Post, Below, Below, None,
 596     None, None, None, Above,
 597     Above, None, None, Above,
 598     Above, None, None, None,
 599
 600     None, None, None, None,
 601     None, None, None, None,
 602     None, None, None, None,
 603     None, None, None, None,
 604
 605     None, None, None, None,
 606     None, None, None, None,
 607     None, None, None, None,
 608     None, None, None, None,
 609
 610     Above, Above, None, None,
 611     None, None, None, None,
 612     None, None, None, None,
 613     None, None, None, None,
 614
 615     // Gujarati
 616     None, Above, Above, Post,
 617     None, None, None, None,
 618     None, None, None, None,
 619     None, None, None, None,
 620
 621     None, None, None, None,
 622     None, None, None, None,
 623     None, None, None, None,
 624     None, None, None, None,
 625
 626     None, None, None, None,
 627     None, None, None, None,
 628     None, None, None, None,
 629     None, None, None, None,
 630
 631     Below, None, None, None,
 632     None, None, None, None,
 633     None, None, None, None,
 634     None, None, Post, Pre,
 635
 636     Post, Below, Below, Below,
 637     Below, Above, None, Above,
 638     Above, Post, None, Post,
 639     Post, None, None, None,
 640
 641     None, None, None, None,
 642     None, None, None, None,
 643     None, None, None, None,
 644     None, None, None, None,
 645
 646     None, None, Below, Below,
 647     None, None, None, None,
 648     None, None, None, None,
 649     None, None, None, None,
 650
 651     None, None, None, None,
 652     None, None, None, None,
 653     None, None, None, None,
 654     None, None, None, None,
 655
 656     // Oriya
 657     None, Above, Post, Post,
 658     None, None, None, None,
 659     None, None, None, None,
 660     None, None, None, None,
 661
 662     None, None, None, None,
 663     None, None, None, None,
 664     None, None, None, None,
 665     None, None, None, None,
 666
 667     None, None, None, None,
 668     Below, None, None, None,
 669     Below, None, None, None,
 670     Below, Below, Below, Post,
 671
 672     Below, None, Below, Below,
 673     None, None, None, None,
 674     None, None, None, None,
 675     None, None, Post, Above,
 676
 677     Post, Below, Below, Below,
 678     None, None, None, Pre,
 679     Split, None, None, Split,
 680     Split, None, None, None,
 681
 682     None, None, None, None,
 683     None, None, Above, Post,
 684     None, None, None, None,
 685     None, None, None, Post,
 686
 687     None, None, None, None,
 688     None, None, None, None,
 689     None, None, None, None,
 690     None, None, None, None,
 691
 692     None, Below, None, None,
 693     None, None, None, None,
 694     None, None, None, None,
 695     None, None, None, None,
 696
 697     // Tamil
 698     None, None, Above, None,
 699     None, None, None, None,
 700     None, None, None, None,
 701     None, None, None, None,
 702
 703     None, None, None, None,
 704     None, None, None, None,
 705     None, None, None, None,
 706     None, None, None, None,
 707
 708     None, None, None, None,
 709     None, None, None, None,
 710     None, None, None, None,
 711     None, None, None, None,
 712
 713     None, None, None, None,
 714     None, None, None, None,
 715     None, None, None, None,
 716     None, None, Post, Post,
 717
 718     Above, Below, Below, None,
 719     None, None, Pre, Pre,
 720     Pre, None, Split, Split,
 721     Split, Halant, None, None,
 722
 723     None, None, None, None,
 724     None, None, None, Post,
 725     None, None, None, None,
 726     None, None, None, None,
 727
 728     None, None, None, None,
 729     None, None, None, None,
 730     None, None, None, None,
 731     None, None, None, None,
 732
 733     None, None, None, None,
 734     None, None, None, None,
 735     None, None, None, None,
 736     None, None, None, None,
 737
 738     // Telugu
 739     None, Post, Post, Post,
 740     None, None, None, None,
 741     None, None, None, None,
 742     None, None, None, None,
 743
 744     None, None, None, None,
 745     None, Below, Below, Below,
 746     Below, Below, Below, Below,
 747     Below, Below, Below, Below,
 748
 749     Below, Below, Below, Below,
 750     Below, Below, Below, Below,
 751     Below, None, Below, Below,
 752     Below, Below, Below, Below,
 753
 754     Below, None, Below, Below,
 755     None, Below, Below, Below,
 756     Below, Below, None, None,
 757     None, None, Post, Above,
 758
 759     Above, Post, Post, Post,
 760     Post, None, Above, Above,
 761     Split, None, Post, Above,
 762     Above, Halant, None, None,
 763
 764     None, None, None, None,
 765     None, Above, Below, None,
 766     None, None, None, None,
 767     None, None, None, None,
 768
 769     None, None, None, None,
 770     None, None, None, None,
 771     None, None, None, None,
 772     None, None, None, None,
 773
 774     None, None, None, None,
 775     None, None, None, None,
 776     None, None, None, None,
 777     None, None, None, None,
 778
 779     // Kannada
 780     None, None, Post, Post,
 781     None, None, None, None,
 782     None, None, None, None,
 783     None, None, None, None,
 784
 785     None, None, None, None,
 786     None, Below, Below, Below,
 787     Below, Below, Below, Below,
 788     Below, Below, Below, Below,
 789
 790     Below, Below, Below, Below,
 791     Below, Below, Below, Below,
 792     Below, Below, Below, Below,
 793     Below, Below, Below, Below,
 794
 795     Below, None, Below, Below,
 796     None, Below, Below, Below,
 797     Below, Below, None, None,
 798     None, None, Post, Above,
 799
 800     Split, Post, Post, Post,
 801     Post, None, Above, Split,
 802     Split, None, Split, Split,
 803     Above, Halant, None, None,
 804
 805     None, None, None, None,
 806     None, Post, Post, None,
 807     None, None, None, None,
 808     None, None, Below, None,
 809
 810     None, None, Below, Below,
 811     None, None, None, None,
 812     None, None, None, None,
 813     None, None, None, None,
 814
 815     None, None, None, None,
 816     None, None, None, None,
 817     None, None, None, None,
 818     None, None, None, None,
 819
 820     // Malayalam
 821     None, None, Post, Post,
 822     None, None, None, None,
 823     None, None, None, None,
 824     None, None, None, None,
 825
 826     None, None, None, None,
 827     None, None, None, None,
 828     None, None, None, None,
 829     None, None, None, None,
 830
 831     None, None, None, None,
 832     None, None, None, None,
 833     None, None, None, None,
 834     None, None, None, Post,
 835
 836     Post, None, Below, None,
 837     None, Post, None, None,
 838     None, None, None, None,
 839     None, None, Post, Post,
 840
 841     Post, Post, Post, Post,
 842     None, None, Pre, Pre,
 843     Pre, None, Split, Split,
 844     Split, Halant, None, None,
 845
 846     None, None, None, None,
 847     None, None, None, Post,
 848     None, None, None, None,
 849     None, None, None, None,
 850
 851     None, None, None, None,
 852     None, None, None, None,
 853     None, None, None, None,
 854     None, None, None, None,
 855
 856     None, None, None, None,
 857     None, None, None, None,
 858     None, None, None, None,
 859     None, None, None, None,
 860
 861     // Sinhala
 862     None, None, Post, Post,
 863     None, None, None, None,
 864     None, None, None, None,
 865     None, None, None, None,
 866
 867     None, None, None, None,
 868     None, None, None, None,
 869     None, None, None, None,
 870     None, None, None, None,
 871
 872     None, None, None, None,
 873     None, None, None, None,
 874     None, None, None, None,
 875     None, None, None, None,
 876
 877     None, None, None, None,
 878     None, None, None, None,
 879     None, None, None, None,
 880     None, None, None, None,
 881
 882     None, None, None, None,
 883     None, None, None, None,
 884     None, None, None, None,
 885     None, None, None, Post,
 886
 887     Post, Post, Above, Above,
 888     Below, None, Below, None,
 889     Post, Pre, Split, Pre,
 890     Split, Split, Split, Post,
 891
 892     None, None, None, None,
 893     None, None, None, None,
 894     None, None, None, None,
 895     None, None, None, None,
 896
 897     None, None, Post, Post,
 898     None, None, None, None,
 899     None, None, None, None,
 900     None, None, None, None
 901 };
 902
 903 static inline Form form(unsigned short uc) {
 904     if (uc < 0x900 || uc > 0xdff) {
 905         if (uc == 0x25cc)
 906             return Consonant;
 907         if (uc == 0x200c || uc == 0x200d)
 908             return Control;
 909         return Other;
 910     }
 911     return (Form)indicForms[uc-0x900];
 912 }
 913
 914 static inline Position indic_position(unsigned short uc) {
 915     if (uc < 0x900 || uc > 0xdff)
 916         return None;
 917     return (Position) indicPosition[uc-0x900];
 918 }
 919
 920
 921 enum IndicScriptProperties {
 922     HasReph = 0x01,
 923     HasSplit = 0x02
 924 };
 925
 926 const hb_uint8 scriptProperties[10] = {
 927     // Devanagari,
 928     HasReph,
 929     // Bengali,
 930     HasReph|HasSplit,
 931     // Gurmukhi,
 932     0,
 933     // Gujarati,
 934     HasReph,
 935     // Oriya,
 936     HasReph|HasSplit,
 937     // Tamil,
 938     HasSplit,
 939     // Telugu,
 940     HasSplit,
 941     // Kannada,
 942     HasSplit|HasReph,
 943     // Malayalam,
 944     HasSplit,
 945     // Sinhala,
 946     HasSplit
 947 };
 948
 949 struct IndicOrdering {
 950     Form form;
 951     Position position;
 952 };
 953
 954 static const IndicOrdering devanagari_order [] = {
 955     { Consonant, Below },
 956     { Matra, Below },
 957     { VowelMark, Below },
 958     { StressMark, Below },
 959     { Matra, Above },
 960     { Matra, Post },
 961     { Consonant, Reph },
 962     { VowelMark, Above },
 963     { StressMark, Above },
 964     { VowelMark, Post },
 965     { (Form)0, None }
 966 };
 967
 968 static const IndicOrdering bengali_order [] = {
 969     { Consonant, Below },
 970     { Matra, Below },
 971     { Matra, Above },
 972     { Consonant, Reph },
 973     { VowelMark, Above },
 974     { Consonant, Post },
 975     { Matra, Post },
 976     { VowelMark, Post },
 977     { (Form)0, None }
 978 };
 979
 980 static const IndicOrdering gurmukhi_order [] = {
 981     { Consonant, Below },
 982     { Matra, Below },
 983     { Matra, Above },
 984     { Consonant, Post },
 985     { Matra, Post },
 986     { VowelMark, Above },
 987     { (Form)0, None }
 988 };
 989
 990 static const IndicOrdering tamil_order [] = {
 991     { Matra, Above },
 992     { Matra, Post },
 993     { VowelMark, Post },
 994     { (Form)0, None }
 995 };
 996
 997 static const IndicOrdering telugu_order [] = {
 998     { Matra, Above },
 999     { Matra, Below },
1000     { Matra, Post },
1001     { Consonant, Below },
1002     { Consonant, Post },
1003     { VowelMark, Post },
1004     { (Form)0, None }
1005 };
1006
1007 static const IndicOrdering kannada_order [] = {
1008     { Matra, Above },
1009     { Matra, Post },
1010     { Consonant, Below },
1011     { Consonant, Post },
1012     { LengthMark, Post },
1013     { Consonant, Reph },
1014     { VowelMark, Post },
1015     { (Form)0, None }
1016 };
1017
1018 static const IndicOrdering malayalam_order [] = {
1019     { Consonant, Below },
1020     { Matra, Below },
1021     { Consonant, Reph },
1022     { Consonant, Post },
1023     { Matra, Post },
1024     { VowelMark, Post },
1025     { (Form)0, None }
1026 };
1027
1028 static const IndicOrdering sinhala_order [] = {
1029     { Matra, Below },
1030     { Matra, Above },
1031     { Matra, Post },
1032     { VowelMark, Post },
1033     { (Form)0, None }
1034 };
1035
1036 static const IndicOrdering * const indic_order[] = {
1037     devanagari_order, // Devanagari
1038     bengali_order, // Bengali
1039     gurmukhi_order, // Gurmukhi
1040     devanagari_order, // Gujarati
1041     bengali_order, // Oriya
1042     tamil_order, // Tamil
1043     telugu_order, // Telugu
1044     kannada_order, // Kannada
1045     malayalam_order, // Malayalam
1046     sinhala_order // Sinhala
1047 };
1048
1049
1050
1051 // vowel matras that have to be split into two parts.
1052 static const unsigned short split_matras[]  = {
1053     //  matra, split1, split2, split3
1054
1055     // bengalis
1056     0x9cb, 0x9c7, 0x9be, 0x0,
1057     0x9cc, 0x9c7, 0x9d7, 0x0,
1058     // oriya
1059     0xb48, 0xb47, 0xb56, 0x0,
1060     0xb4b, 0xb47, 0xb3e, 0x0,
1061     0xb4c, 0xb47, 0xb57, 0x0,
1062     // tamil
1063     0xbca, 0xbc6, 0xbbe, 0x0,
1064     0xbcb, 0xbc7, 0xbbe, 0x0,
1065     0xbcc, 0xbc6, 0xbd7, 0x0,
1066     // telugu
1067     0xc48, 0xc46, 0xc56, 0x0,
1068     // kannada
1069     0xcc0, 0xcbf, 0xcd5, 0x0,
1070     0xcc7, 0xcc6, 0xcd5, 0x0,
1071     0xcc8, 0xcc6, 0xcd6, 0x0,
1072     0xcca, 0xcc6, 0xcc2, 0x0,
1073     0xccb, 0xcc6, 0xcc2, 0xcd5,
1074     // malayalam
1075     0xd4a, 0xd46, 0xd3e, 0x0,
1076     0xd4b, 0xd47, 0xd3e, 0x0,
1077     0xd4c, 0xd46, 0xd57, 0x0,
1078     // sinhala
1079     0xdda, 0xdd9, 0xdca, 0x0,
1080     0xddc, 0xdd9, 0xdcf, 0x0,
1081     0xddd, 0xdd9, 0xdcf, 0xdca,
1082     0xdde, 0xdd9, 0xddf, 0x0,
1083     0xffff
1084 };
1085
1086 static inline void splitMatra(unsigned short *reordered, int matra, int &len)
1087 {
1088     unsigned short matra_uc = reordered[matra];
1089     //qDebug("matra=%d, reordered[matra]=%x", matra, reordered[matra]);
1090
1091     const unsigned short *split = split_matras;
1092     while (split[0] < matra_uc)
1093         split += 4;
1094
1095     assert(*split == matra_uc);
1096     ++split;
1097
1098     int added_chars = split[2] == 0x0 ? 1 : 2;
1099
1100     memmove(reordered + matra + added_chars, reordered + matra, (len-matra)*sizeof(unsigned short));
1101     reordered[matra] = split[0];
1102     reordered[matra+1] = split[1];
1103     if(added_chars == 2)
1104         reordered[matra+2] = split[2];
1105     len += added_chars;
1106 }
1107
1108 #ifndef NO_OPENTYPE
1109 static const HB_OpenTypeFeature indic_features[] = {
1110     { HB_MAKE_TAG('l', 'o', 'c', 'a'), LocaProperty },
1111     { HB_MAKE_TAG('c', 'c', 'm', 'p'), CcmpProperty },
1112     { HB_MAKE_TAG('i', 'n', 'i', 't'), InitProperty },
1113     { HB_MAKE_TAG('n', 'u', 'k', 't'), NuktaProperty },
1114     { HB_MAKE_TAG('a', 'k', 'h', 'n'), AkhantProperty },
1115     { HB_MAKE_TAG('r', 'p', 'h', 'f'), RephProperty },
1116     { HB_MAKE_TAG('b', 'l', 'w', 'f'), BelowFormProperty },
1117     { HB_MAKE_TAG('h', 'a', 'l', 'f'), HalfFormProperty },
1118     { HB_MAKE_TAG('p', 's', 't', 'f'), PostFormProperty },
1119     { HB_MAKE_TAG('c', 'j', 'c', 't'), ConjunctFormProperty },
1120     { HB_MAKE_TAG('v', 'a', 't', 'u'), VattuProperty },
1121     { HB_MAKE_TAG('p', 'r', 'e', 's'), PreSubstProperty },
1122     { HB_MAKE_TAG('b', 'l', 'w', 's'), BelowSubstProperty },
1123     { HB_MAKE_TAG('a', 'b', 'v', 's'), AboveSubstProperty },
1124     { HB_MAKE_TAG('p', 's', 't', 's'), PostSubstProperty },
1125     { HB_MAKE_TAG('h', 'a', 'l', 'n'), HalantProperty },
1126     { HB_MAKE_TAG('c', 'a', 'l', 't'), IndicCaltProperty },
1127     { 0, 0 }
1128 };
1129 #endif
1130
1131 // #define INDIC_DEBUG
1132 #ifdef INDIC_DEBUG
1133 #define IDEBUG hb_debug
1134 #include <stdarg.h>
1135
1136 static void hb_debug(const char *msg, ...)
1137 {
1138     va_list ap;
1139     va_start(ap, msg); // use variable arg list
1140     vfprintf(stderr, msg, ap);
1141     va_end(ap);
1142     fprintf(stderr, "\n");
1143 }
1144
1145 #else
1146 #define IDEBUG if(0) printf
1147 #endif
1148
1149 #if 0 //def INDIC_DEBUG
1150 static QString propertiesToString(int properties)
1151 {
1152     QString res;
1153     properties = ~properties;
1154     if (properties & LocaProperty)
1155         res += "Loca ";
1156     if (properties & CcmpProperty)
1157         res += "Ccmp ";
1158     if (properties & InitProperty)
1159         res += "Init ";
1160     if (properties & NuktaProperty)
1161         res += "Nukta ";
1162     if (properties & AkhantProperty)
1163         res += "Akhant ";
1164     if (properties & RephProperty)
1165         res += "Reph ";
1166     if (properties & PreFormProperty)
1167         res += "PreForm ";
1168     if (properties & BelowFormProperty)
1169         res += "BelowForm ";
1170     if (properties & AboveFormProperty)
1171         res += "AboveForm ";
1172     if (properties & HalfFormProperty)
1173         res += "HalfForm ";
1174     if (properties & PostFormProperty)
1175         res += "PostForm ";
1176     if (properties & ConjunctFormProperty)
1177         res += "PostForm ";
1178     if (properties & VattuProperty)
1179         res += "Vattu ";
1180     if (properties & PreSubstProperty)
1181         res += "PreSubst ";
1182     if (properties & BelowSubstProperty)
1183         res += "BelowSubst ";
1184     if (properties & AboveSubstProperty)
1185         res += "AboveSubst ";
1186     if (properties & PostSubstProperty)
1187         res += "PostSubst ";
1188     if (properties & HalantProperty)
1189         res += "Halant ";
1190     if (properties & CligProperty)
1191         res += "Clig ";
1192     if (properties & IndicCaltProperty)
1193         res += "Calt ";
1194     return res;
1195 }
1196 #endif
1197
1198 static bool indic_shape_syllable(HB_Bool openType, HB_ShaperItem *item, bool invalid)
1199 {
1200     HB_Script script = item->item.script;
1201     assert(script >= HB_Script_Devanagari && script <= HB_Script_Sinhala);
1202     const unsigned short script_base = 0x0900 + 0x80*(script-HB_Script_Devanagari);
1203     const unsigned short ra = script_base + 0x30;
1204     const unsigned short halant = script_base + 0x4d;
1205     const unsigned short nukta = script_base + 0x3c;
1206     bool control = false;
1207
1208     int len = (int)item->item.length;
1209     IDEBUG(">>>>> indic shape: from=%d, len=%d invalid=%d", item->item.pos, item->item.length, invalid);
1210
1211     if ((int)item->num_glyphs < len+4) {
1212         item->num_glyphs = len+4;
1213         return false;
1214     }
1215
1216     HB_STACKARRAY(HB_UChar16, reordered, len + 4);
1217     HB_STACKARRAY(hb_uint8, position, len + 4);
1218
1219     unsigned char properties = scriptProperties[script-HB_Script_Devanagari];
1220
1221     if (invalid) {
1222         *reordered = 0x25cc;
1223         memcpy(reordered+1, item->string + item->item.pos, len*sizeof(HB_UChar16));
1224         len++;
1225     } else {
1226         memcpy(reordered, item->string + item->item.pos, len*sizeof(HB_UChar16));
1227     }
1228     if (reordered[len-1] == 0x200c) // zero width non joiner
1229         len--;
1230
1231     int i;
1232     int base = 0;
1233     int reph = -1;
1234
1235 #ifdef INDIC_DEBUG
1236     IDEBUG("original:");
1237     for (i = 0; i < len; i++) {
1238         IDEBUG("    %d: %4x", i, reordered[i]);
1239     }
1240 #endif
1241
1242     if (len != 1) {
1243         HB_UChar16 *uc = reordered;
1244         bool beginsWithRa = false;
1245
1246         // Rule 1: find base consonant
1247         //
1248         // The shaping engine finds the base consonant of the
1249         // syllable, using the following algorithm: starting from the
1250         // end of the syllable, move backwards until a consonant is
1251         // found that does not have a below-base or post-base form
1252         // (post-base forms have to follow below-base forms), or
1253         // arrive at the first consonant. The consonant stopped at
1254         // will be the base.
1255         //
1256         //  * If the syllable starts with Ra + H (in a script that has
1257         //    'Reph'), Ra is excluded from candidates for base
1258         //    consonants.
1259         //
1260         // * In Kannada and Telugu, the base consonant cannot be
1261         //   farther than 3 consonants from the end of the syllable.
1262         // #### replace the HasReph property by testing if the feature exists in the font!
1263         if (form(*uc) == Consonant || (script == HB_Script_Bengali && form(*uc) == IndependentVowel)) {
1264             if ((properties & HasReph) && (len > 2) &&
1265                 (*uc == ra || *uc == 0x9f0) && *(uc+1) == halant)
1266                 beginsWithRa = true;
1267
1268             if (beginsWithRa && form(*(uc+2)) == Control)
1269                 beginsWithRa = false;
1270
1271             base = (beginsWithRa ? 2 : 0);
1272             IDEBUG("    length = %d, beginsWithRa = %d, base=%d", len, beginsWithRa, base);
1273
1274             int lastConsonant = 0;
1275             int matra = -1;
1276             // we remember:
1277             // * the last consonant since we need it for rule 2
1278             // * the matras position for rule 3 and 4
1279
1280             // figure out possible base glyphs
1281             memset(position, 0, len);
1282             if (script == HB_Script_Devanagari || script == HB_Script_Gujarati) {
1283                 bool vattu = false;
1284                 for (i = base; i < len; ++i) {
1285                     position[i] = form(uc[i]);
1286                     if (position[i] == Consonant) {
1287                         lastConsonant = i;
1288                         vattu = (!vattu && uc[i] == ra);
1289                         if (vattu) {
1290                             IDEBUG("excluding vattu glyph at %d from base candidates", i);
1291                             position[i] = Vattu;
1292                         }
1293                     } else if (position[i] == Matra) {
1294                         matra = i;
1295                     }
1296                 }
1297             } else {
1298                 for (i = base; i < len; ++i) {
1299                     position[i] = form(uc[i]);
1300                     if (position[i] == Consonant)
1301                         lastConsonant = i;
1302                     else if (matra < 0 && position[i] == Matra)
1303                         matra = i;
1304                 }
1305             }
1306             int skipped = 0;
1307             Position pos = Post;
1308             for (i = len-1; i >= base; i--) {
1309                 if (position[i] != Consonant && (position[i] != Control || script == HB_Script_Kannada))
1310                     continue;
1311
1312                 if (i < len-1 && position[i] == Control && position[i+1] == Consonant) {
1313                     base = i+1;
1314                     break;
1315                 }
1316
1317                 Position charPosition = indic_position(uc[i]);
1318                 if (pos == Post && charPosition == Post) {
1319                     pos = Post;
1320                 } else if ((pos == Post || pos == Below) && charPosition == Below) {
1321                     if (script == HB_Script_Devanagari || script == HB_Script_Gujarati)
1322                         base = i;
1323                     pos = Below;
1324                 } else {
1325                     base = i;
1326                     break;
1327                 }
1328                 if (skipped == 2 && (script == HB_Script_Kannada || script == HB_Script_Telugu)) {
1329                     base = i;
1330                     break;
1331                 }
1332                 ++skipped;
1333             }
1334
1335             IDEBUG("    base consonant at %d skipped=%d, lastConsonant=%d", base, skipped, lastConsonant);
1336
1337             // Rule 2:
1338             //
1339             // If the base consonant is not the last one, Uniscribe
1340             // moves the halant from the base consonant to the last
1341             // one.
1342             if (lastConsonant > base) {
1343                 int halantPos = 0;
1344                 if (uc[base+1] == halant)
1345                     halantPos = base + 1;
1346                 else if (uc[base+1] == nukta && uc[base+2] == halant)
1347                     halantPos = base + 2;
1348                 if (halantPos > 0) {
1349                     IDEBUG("    moving halant from %d to %d!", base+1, lastConsonant);
1350                     for (i = halantPos; i < lastConsonant; i++)
1351                         uc[i] = uc[i+1];
1352                     uc[lastConsonant] = halant;
1353                 }
1354             }
1355
1356             // Rule 3:
1357             //
1358             // If the syllable starts with Ra + H, Uniscribe moves
1359             // this combination so that it follows either:
1360
1361             // * the post-base 'matra' (if any) or the base consonant
1362             //   (in scripts that show similarity to Devanagari, i.e.,
1363             //   Devanagari, Gujarati, Bengali)
1364             // * the base consonant (other scripts)
1365             // * the end of the syllable (Kannada)
1366
1367             Position matra_position = None;
1368             if (matra > 0)
1369                 matra_position = indic_position(uc[matra]);
1370             IDEBUG("    matra at %d with form %d, base=%d", matra, matra_position, base);
1371
1372             if (beginsWithRa && base != 0) {
1373                 int toPos = base+1;
1374                 if (toPos < len && uc[toPos] == nukta)
1375                     toPos++;
1376                 if (toPos < len && uc[toPos] == halant)
1377                     toPos++;
1378                 if (toPos < len && uc[toPos] == 0x200d)
1379                     toPos++;
1380                 if (toPos < len-1 && uc[toPos] == ra && uc[toPos+1] == halant)
1381                     toPos += 2;
1382                 if (script == HB_Script_Devanagari || script == HB_Script_Gujarati || script == HB_Script_Bengali) {
1383                     if (matra_position == Post || matra_position == Split) {
1384                         toPos = matra+1;
1385                         matra -= 2;
1386                     }
1387                 } else if (script == HB_Script_Kannada) {
1388                     toPos = len;
1389                     matra -= 2;
1390                 }
1391
1392                 IDEBUG("moving leading ra+halant to position %d", toPos);
1393                 for (i = 2; i < toPos; i++)
1394                     uc[i-2] = uc[i];
1395                 uc[toPos-2] = ra;
1396                 uc[toPos-1] = halant;
1397                 base -= 2;
1398                 if (properties & HasReph)
1399                     reph = toPos-2;
1400             }
1401
1402             // Rule 4:
1403
1404             // Uniscribe splits two- or three-part matras into their
1405             // parts. This splitting is a character-to-character
1406             // operation).
1407             //
1408             //      Uniscribe describes some moving operations for these
1409             //      matras here. For shaping however all pre matras need
1410             //      to be at the beginning of the syllable, so we just move
1411             //      them there now.
1412             if (matra_position == Split) {
1413                 splitMatra(uc, matra, len);
1414                 // Handle three-part matras (0xccb in Kannada)
1415                 matra_position = indic_position(uc[matra]);
1416             }
1417
1418             if (matra_position == Pre) {
1419                 unsigned short m = uc[matra];
1420                 while (matra--)
1421                     uc[matra+1] = uc[matra];
1422                 uc[0] = m;
1423                 base++;
1424             }
1425         }
1426
1427         // Rule 5:
1428         //
1429         // Uniscribe classifies consonants and 'matra' parts as
1430         // pre-base, above-base (Reph), below-base or post-base. This
1431         // classification exists on the character code level and is
1432         // language-dependent, not font-dependent.
1433         for (i = 0; i < base; ++i)
1434             position[i] = Pre;
1435         position[base] = Base;
1436         for (i = base+1; i < len; ++i) {
1437             position[i] = indic_position(uc[i]);
1438             // #### replace by adjusting table
1439             if (uc[i] == nukta || uc[i] == halant)
1440                 position[i] = Inherit;
1441         }
1442         if (reph > 0) {
1443             // recalculate reph, it might have changed.
1444             for (i = base+1; i < len; ++i)
1445                 if (uc[i] == ra)
1446                     reph = i;
1447             position[reph] = Reph;
1448             position[reph+1] = Inherit;
1449         }
1450
1451         // all reordering happens now to the chars after the base
1452         int fixed = base+1;
1453         if (fixed < len && uc[fixed] == nukta)
1454             fixed++;
1455         if (fixed < len && uc[fixed] == halant)
1456             fixed++;
1457         if (fixed < len && uc[fixed] == 0x200d)
1458             fixed++;
1459
1460 #ifdef INDIC_DEBUG
1461         for (i = fixed; i < len; ++i)
1462             IDEBUG("position[%d] = %d, form=%d uc=%x", i, position[i], form(uc[i]), uc[i]);
1463 #endif
1464         // we continuosly position the matras and vowel marks and increase the fixed
1465         // until we reached the end.
1466         const IndicOrdering *finalOrder = indic_order[script-HB_Script_Devanagari];
1467
1468         IDEBUG("    reordering pass:");
1469         IDEBUG("        base=%d fixed=%d", base, fixed);
1470         int toMove = 0;
1471         while (finalOrder[toMove].form && fixed < len-1) {
1472             IDEBUG("        fixed = %d, toMove=%d, moving form %d with pos %d", fixed, toMove, finalOrder[toMove].form, finalOrder[toMove].position);
1473             for (i = fixed; i < len; i++) {
1474 //                IDEBUG() << "           i=" << i << "uc=" << hex << uc[i] << "form=" << form(uc[i])
1475 //                         << "position=" << position[i];
1476                 if (form(uc[i]) == finalOrder[toMove].form &&
1477                      position[i] == finalOrder[toMove].position) {
1478                     // need to move this glyph
1479                     int to = fixed;
1480                     if (i < len-1 && position[i+1] == Inherit) {
1481                         IDEBUG("         moving two chars from %d to %d", i, to);
1482                         unsigned short ch = uc[i];
1483                         unsigned short ch2 = uc[i+1];
1484                         unsigned char pos = position[i];
1485                         for (int j = i+1; j > to+1; j--) {
1486                             uc[j] = uc[j-2];
1487                             position[j] = position[j-2];
1488                         }
1489                         uc[to] = ch;
1490                         uc[to+1] = ch2;
1491                         position[to] = pos;
1492                         position[to+1] = pos;
1493                         fixed += 2;
1494                     } else {
1495                         IDEBUG("         moving one char from %d to %d", i, to);
1496                         unsigned short ch = uc[i];
1497                         unsigned char pos = position[i];
1498                         for (int j = i; j > to; j--) {
1499                             uc[j] = uc[j-1];
1500                             position[j] = position[j-1];
1501                         }
1502                         uc[to] = ch;
1503                         position[to] = pos;
1504                         fixed++;
1505                     }
1506                 }
1507             }
1508             toMove++;
1509         }
1510
1511     }
1512
1513     if (reph > 0) {
1514         // recalculate reph, it might have changed.
1515         for (i = base+1; i < len; ++i)
1516             if (reordered[i] == ra)
1517                 reph = i;
1518     }
1519
1520 #ifndef NO_OPENTYPE
1521     const int availableGlyphs = item->num_glyphs;
1522 #endif
1523     if (!item->font->klass->convertStringToGlyphIndices(item->font,
1524                                                         reordered, len,
1525                                                         item->glyphs, &item->num_glyphs,
1526                                                         item->item.bidiLevel % 2))
1527         goto error;
1528
1529
1530     IDEBUG("  base=%d, reph=%d", base, reph);
1531     IDEBUG("reordered:");
1532     for (i = 0; i < len; i++) {
1533         item->attributes[i].mark = false;
1534         item->attributes[i].clusterStart = false;
1535         item->attributes[i].justification = 0;
1536         item->attributes[i].zeroWidth = false;
1537         IDEBUG("    %d: %4x", i, reordered[i]);
1538     }
1539
1540     // now we have the syllable in the right order, and can start running it through open type.
1541
1542     for (i = 0; i < len; ++i)
1543         control |= (form(reordered[i]) == Control);
1544
1545 #ifndef NO_OPENTYPE
1546     if (openType) {
1547
1548         // we need to keep track of where the base glyph is for some
1549         // scripts and use the cluster feature for this.  This
1550         // also means we have to correct the logCluster output from
1551         // the open type engine manually afterwards.  for indic this
1552         // is rather simple, as all chars just point to the first
1553         // glyph in the syllable.
1554         HB_STACKARRAY(unsigned short, clusters, len);
1555         HB_STACKARRAY(unsigned int, properties, len);
1556
1557         for (i = 0; i < len; ++i)
1558             clusters[i] = i;
1559
1560         // features we should always apply
1561         for (i = 0; i < len; ++i)
1562             properties[i] = ~(LocaProperty
1563                               | CcmpProperty
1564                               | NuktaProperty
1565                               | VattuProperty
1566                               | ConjunctFormProperty
1567                               | PreSubstProperty
1568                               | BelowSubstProperty
1569                               | AboveSubstProperty
1570                               | PostSubstProperty
1571                               | HalantProperty
1572                               | IndicCaltProperty
1573                               | PositioningProperties);
1574
1575         // Loca always applies
1576         // Ccmp always applies
1577         // Init
1578         if (item->item.pos == 0
1579             || !(isLetter(item->string[item->item.pos-1]) || isMark(item->string[item->item.pos-1])))
1580             properties[0] &= ~InitProperty;
1581
1582         // Nukta always applies
1583         // Akhant
1584         for (i = 0; i <= base; ++i)
1585             properties[i] &= ~AkhantProperty;
1586         // Reph
1587         if (reph >= 0) {
1588             properties[reph] &= ~RephProperty;
1589             properties[reph+1] &= ~RephProperty;
1590         }
1591         // BelowForm
1592         for (i = base+1; i < len; ++i)
1593             properties[i] &= ~BelowFormProperty;
1594
1595         if (script == HB_Script_Devanagari || script == HB_Script_Gujarati) {
1596             // vattu glyphs need this aswell
1597             bool vattu = false;
1598             for (i = base-2; i > 1; --i) {
1599                 if (form(reordered[i]) == Consonant) {
1600                     vattu = (!vattu && reordered[i] == ra);
1601                     if (vattu) {
1602                         IDEBUG("forming vattu ligature at %d", i);
1603                         properties[i] &= ~BelowFormProperty;
1604                         properties[i+1] &= ~BelowFormProperty;
1605                     }
1606                 }
1607             }
1608         }
1609         // HalfFormProperty
1610         for (i = 0; i < base; ++i)
1611             properties[i] &= ~HalfFormProperty;
1612         if (control) {
1613             for (i = 2; i < len; ++i) {
1614                 if (reordered[i] == 0x200d /* ZWJ */) {
1615                     properties[i-1] &= ~HalfFormProperty;
1616                     properties[i-2] &= ~HalfFormProperty;
1617                 } else if (reordered[i] == 0x200c /* ZWNJ */) {
1618                     properties[i-1] &= ~HalfFormProperty;
1619                     properties[i-2] &= ~HalfFormProperty;
1620                 }
1621             }
1622         }
1623         // PostFormProperty
1624         for (i = base+1; i < len; ++i)
1625             properties[i] &= ~PostFormProperty;
1626         // vattu always applies
1627         // pres always applies
1628         // blws always applies
1629         // abvs always applies
1630         // psts always applies
1631         // halant always applies
1632         // calt always applies
1633
1634 #ifdef INDIC_DEBUG
1635 //        {
1636 //            IDEBUG("OT properties:");
1637 //            for (int i = 0; i < len; ++i)
1638 //                qDebug("    i: %s", ::propertiesToString(properties[i]).toLatin1().data());
1639 //        }
1640 #endif
1641
1642         // initialize
1643         item->log_clusters = clusters;
1644         HB_OpenTypeShape(item, properties);
1645
1646         int newLen = item->face->buffer->in_length;
1647         HB_GlyphItem otl_glyphs = item->face->buffer->in_string;
1648
1649         // move the left matra back to its correct position in malayalam and tamil
1650         if ((script == HB_Script_Malayalam || script == HB_Script_Tamil) && (form(reordered[0]) == Matra)) {
1651 //             qDebug("reordering matra, len=%d", newLen);
1652             // need to find the base in the shaped string and move the matra there
1653             int basePos = 0;
1654             while (basePos < newLen && (int)otl_glyphs[basePos].cluster <= base)
1655                 basePos++;
1656             --basePos;
1657             if (basePos < newLen && basePos > 1) {
1658 //                 qDebug("moving prebase matra to position %d in syllable newlen=%d", basePos, newLen);
1659                 HB_GlyphItemRec m = otl_glyphs[0];
1660                 --basePos;
1661                 for (i = 0; i < basePos; ++i)
1662                     otl_glyphs[i] = otl_glyphs[i+1];
1663                 otl_glyphs[basePos] = m;
1664             }
1665         }
1666
1667         HB_Bool positioned = HB_OpenTypePosition(item, availableGlyphs, false);
1668
1669         HB_FREE_STACKARRAY(clusters);
1670         HB_FREE_STACKARRAY(properties);
1671
1672         if (!positioned)
1673             goto error;
1674
1675         if (control) {
1676             IDEBUG("found a control char in the syllable");
1677             hb_uint32 i = 0, j = 0;
1678             while (i < item->num_glyphs) {
1679                 if (form(reordered[otl_glyphs[i].cluster]) == Control) {
1680                     ++i;
1681                     if (i >= item->num_glyphs)
1682                         break;
1683                 }
1684                 item->glyphs[j] = item->glyphs[i];
1685                 item->attributes[j] = item->attributes[i];
1686                 ++i;
1687                 ++j;
1688             }
1689             item->num_glyphs = j;
1690         }
1691
1692     } else {
1693         HB_HeuristicPosition(item);
1694     }
1695 #endif // NO_OPENTYPE
1696     item->attributes[0].clusterStart = true;
1697
1698     HB_FREE_STACKARRAY(reordered);
1699     HB_FREE_STACKARRAY(position);
1700
1701     IDEBUG("<<<<<<");
1702     return true;
1703
1704 error:
1705     HB_FREE_STACKARRAY(reordered);
1706     HB_FREE_STACKARRAY(position);
1707     return false;
1708 }
1709
1710 /* syllables are of the form:
1711
1712    (Consonant Nukta? Halant)* Consonant Matra? VowelMark? StressMark?
1713    (Consonant Nukta? Halant)* Consonant Halant
1714    IndependentVowel VowelMark? StressMark?
1715
1716    We return syllable boundaries on invalid combinations aswell
1717 */
1718 static int indic_nextSyllableBoundary(HB_Script script, const HB_UChar16 *s, int start, int end, bool *invalid)
1719 {
1720     *invalid = false;
1721     IDEBUG("indic_nextSyllableBoundary: start=%d, end=%d", start, end);
1722     const HB_UChar16 *uc = s+start;
1723
1724     int pos = 0;
1725     Form state = form(uc[pos]);
1726     IDEBUG("state[%d]=%d (uc=%4x)", pos, state, uc[pos]);
1727     pos++;
1728
1729     if (state != Consonant && state != IndependentVowel) {
1730         if (state != Other)
1731             *invalid = true;
1732         goto finish;
1733     }
1734
1735     while (pos < end - start) {
1736         Form newState = form(uc[pos]);
1737         IDEBUG("state[%d]=%d (uc=%4x)", pos, newState, uc[pos]);
1738         switch(newState) {
1739         case Control:
1740             newState = state;
1741             if (state == Halant && uc[pos] == 0x200d /* ZWJ */)
1742                 break;
1743             // the control character should be the last char in the item
1744             ++pos;
1745             goto finish;
1746         case Consonant:
1747             if (state == Halant && (script != HB_Script_Sinhala || uc[pos-1] == 0x200d /* ZWJ */))
1748                 break;
1749             goto finish;
1750         case Halant:
1751             if (state == Nukta || state == Consonant)
1752                 break;
1753             // Bengali has a special exception allowing the combination Vowel_A/E + Halant + Ya
1754             if (script == HB_Script_Bengali && pos == 1 &&
1755                  (uc[0] == 0x0985 || uc[0] == 0x098f))
1756                 break;
1757             // Sinhala uses the Halant as a component of certain matras. Allow these, but keep the state on Matra.
1758             if (script == HB_Script_Sinhala && state == Matra) {
1759                 ++pos;
1760                 continue;
1761             }
1762             if (script == HB_Script_Malayalam && state == Matra && uc[pos-1] == 0x0d41) {
1763                 ++pos;
1764                 continue;
1765             }
1766             goto finish;
1767         case Nukta:
1768             if (state == Consonant)
1769                 break;
1770             goto finish;
1771         case StressMark:
1772             if (state == VowelMark)
1773                 break;
1774             // fall through
1775         case VowelMark:
1776             if (state == Matra || state == LengthMark || state == IndependentVowel)
1777                 break;
1778             // fall through
1779         case Matra:
1780             if (state == Consonant || state == Nukta)
1781                 break;
1782             if (state == Matra) {
1783                 // ### needs proper testing for correct two/three part matras
1784                 break;
1785             }
1786             // ### not sure if this is correct. If it is, does it apply only to Bengali or should
1787             // it work for all Indic languages?
1788             // the combination Independent_A + Vowel Sign AA is allowed.
1789             if (script == HB_Script_Bengali && uc[pos] == 0x9be && uc[pos-1] == 0x985)
1790                 break;
1791             if (script == HB_Script_Tamil && state == Matra) {
1792                 if (uc[pos-1] == 0x0bc6 &&
1793                      (uc[pos] == 0xbbe || uc[pos] == 0xbd7))
1794                     break;
1795                 if (uc[pos-1] == 0x0bc7 && uc[pos] == 0xbbe)
1796                     break;
1797             }
1798             goto finish;
1799
1800         case LengthMark:
1801             if (state == Matra) {
1802                 // ### needs proper testing for correct two/three part matras
1803                 break;
1804             }
1805         case IndependentVowel:
1806         case Invalid:
1807         case Other:
1808             goto finish;
1809         }
1810         state = newState;
1811         pos++;
1812     }
1813  finish:
1814     return pos+start;
1815 }
1816
1817 HB_Bool HB_IndicShape(HB_ShaperItem *item)
1818 {
1819     assert(item->item.script >= HB_Script_Devanagari && item->item.script <= HB_Script_Sinhala);
1820
1821     HB_Bool openType = false;
1822 #ifndef NO_OPENTYPE
1823     openType = HB_SelectScript(item, indic_features);
1824 #endif
1825     unsigned short *logClusters = item->log_clusters;
1826
1827     HB_ShaperItem syllable = *item;
1828     int first_glyph = 0;
1829
1830     int sstart = item->item.pos;
1831     int end = sstart + item->item.length;
1832     IDEBUG("indic_shape: from %d length %d", item->item.pos, item->item.length);
1833     while (sstart < end) {
1834         bool invalid;
1835         int send = indic_nextSyllableBoundary(item->item.script, item->string, sstart, end, &invalid);
1836         IDEBUG("syllable from %d, length %d, invalid=%s", sstart, send-sstart,
1837                invalid ? "true" : "false");
1838         syllable.item.pos = sstart;
1839         syllable.item.length = send-sstart;
1840         syllable.glyphs = item->glyphs + first_glyph;
1841         syllable.attributes = item->attributes + first_glyph;
1842         syllable.offsets = item->offsets + first_glyph;
1843         syllable.advances = item->advances + first_glyph;
1844         syllable.num_glyphs = item->num_glyphs - first_glyph;
1845         if (!indic_shape_syllable(openType, &syllable, invalid)) {
1846             IDEBUG("syllable shaping failed, syllable requests %d glyphs", syllable.num_glyphs);
1847             item->num_glyphs += syllable.num_glyphs;
1848             return false;
1849         }
1850         // fix logcluster array
1851         IDEBUG("syllable:");
1852         hb_uint32 g;
1853         for (g = first_glyph; g < first_glyph + syllable.num_glyphs; ++g)
1854             IDEBUG("        %d -> glyph %x", g, item->glyphs[g]);
1855         IDEBUG("    logclusters:");
1856         int i;
1857         for (i = sstart; i < send; ++i) {
1858             IDEBUG("        %d -> glyph %d", i, first_glyph);
1859             logClusters[i-item->item.pos] = first_glyph;
1860         }
1861         sstart = send;
1862         first_glyph += syllable.num_glyphs;
1863     }
1864     item->num_glyphs = first_glyph;
1865     return true;
1866 }
1867
1868 void HB_IndicAttributes(HB_Script script, const HB_UChar16 *text, hb_uint32 from, hb_uint32 len, HB_CharAttributes *attributes)
1869 {
1870     int end = from + len;
1871     const HB_UChar16 *uc = text + from;
1872     attributes += from;
1873     hb_uint32 i = 0;
1874     while (i < len) {
1875         bool invalid;
1876         hb_uint32 boundary = indic_nextSyllableBoundary(script, text, from+i, end, &invalid) - from;
1877          attributes[i].charStop = true;
1878
1879         if (boundary > len-1) boundary = len;
1880         i++;
1881         while (i < boundary) {
1882             attributes[i].charStop = false;
1883             ++uc;
1884             ++i;
1885         }
1886         assert(i == boundary);
1887     }
1888
1889
1890 }
1891
1892