src/gui/text/qtextengine.cpp

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  41
  42 #include "qdebug.h"
  43 #include "qtextformat.h"
  44 #include "qtextformat_p.h"
  45 #include "qtextengine_p.h"
  46 #include "qabstracttextdocumentlayout.h"
  47 #include "qtextlayout.h"
  48 #include "qtextboundaryfinder.h"
  49 #include "qvarlengtharray.h"
  50 #include "qfont.h"
  51 #include "qfont_p.h"
  52 #include "qfontengine_p.h"
  53 #include "qstring.h"
  54 #include <private/qunicodetables_p.h>
  55 #include "qtextdocument_p.h"
  56 #include <qapplication.h>
  57 #include <stdlib.h>
  58
  59
  60 QT_BEGIN_NAMESPACE
  61
  62 namespace {
  63 // Helper class used in QTextEngine::itemize
  64 // keep it out here to allow us to keep supporting various compilers.
  65 class Itemizer {
  66 public:
  67     Itemizer(const QString &string, const QScriptAnalysis *analysis, QScriptItemArray &items)
  68         : m_string(string),
  69         m_analysis(analysis),
  70         m_items(items),
  71         m_splitter(0)
  72     {
  73     }
  74     ~Itemizer()
  75     {
  76         delete m_splitter;
  77     }
  78
  79     /// generate the script items
  80     /// The caps parameter is used to choose the algoritm of splitting text and assiging roles to the textitems
  81     void generate(int start, int length, QFont::Capitalization caps)
  82     {
  83         if ((int)caps == (int)QFont::SmallCaps)
  84             generateScriptItemsSmallCaps(reinterpret_cast<const ushort *>(m_string.unicode()), start, length);
  85         else if(caps == QFont::Capitalize)
  86             generateScriptItemsCapitalize(start, length);
  87         else if(caps != QFont::MixedCase) {
  88             generateScriptItemsAndChangeCase(start, length,
  89                 caps == QFont::AllLowercase ? QScriptAnalysis::Lowercase : QScriptAnalysis::Uppercase);
  90         }
  91         else
  92             generateScriptItems(start, length);
  93     }
  94
  95 private:
  96     enum { MaxItemLength = 4096 };
  97
  98     void generateScriptItemsAndChangeCase(int start, int length, QScriptAnalysis::Flags flags)
  99     {
 100         generateScriptItems(start, length);
 101         if (m_items.isEmpty()) // the next loop won't work in that case
 102             return;
 103         QScriptItemArray::Iterator iter = m_items.end();
 104         do {
 105             iter--;
 106             if (iter->analysis.flags < QScriptAnalysis::TabOrObject)
 107                 iter->analysis.flags = flags;
 108         } while (iter->position > start);
 109     }
 110
 111     void generateScriptItems(int start, int length)
 112     {
 113         if (!length)
 114             return;
 115         const int end = start + length;
 116         for (int i = start + 1; i < end; ++i) {
 117             if ((m_analysis[i] == m_analysis[start])
 118                 && m_analysis[i].flags < QScriptAnalysis::SpaceTabOrObject
 119                 && i - start < MaxItemLength)
 120                 continue;
 121             m_items.append(QScriptItem(start, m_analysis[start]));
 122             start = i;
 123         }
 124         m_items.append(QScriptItem(start, m_analysis[start]));
 125     }
 126
 127     void generateScriptItemsCapitalize(int start, int length)
 128     {
 129         if (!length)
 130             return;
 131
 132         if (!m_splitter)
 133             m_splitter = new QTextBoundaryFinder(QTextBoundaryFinder::Word,
 134                                                  m_string.constData(), m_string.length(),
 135                                                  /*buffer*/0, /*buffer size*/0);
 136
 137         m_splitter->setPosition(start);
 138         QScriptAnalysis itemAnalysis = m_analysis[start];
 139
 140         if (m_splitter->boundaryReasons() & QTextBoundaryFinder::StartWord) {
 141             itemAnalysis.flags = QScriptAnalysis::Uppercase;
 142             m_splitter->toNextBoundary();
 143         }
 144
 145         const int end = start + length;
 146         for (int i = start + 1; i < end; ++i) {
 147
 148             bool atWordBoundary = false;
 149
 150             if (i == m_splitter->position()) {
 151                 if (m_splitter->boundaryReasons() & QTextBoundaryFinder::StartWord
 152                     && m_analysis[i].flags < QScriptAnalysis::TabOrObject)
 153                     atWordBoundary = true;
 154
 155                 m_splitter->toNextBoundary();
 156             }
 157
 158             if (m_analysis[i] == itemAnalysis
 159                 && m_analysis[i].flags < QScriptAnalysis::TabOrObject
 160                 && !atWordBoundary
 161                 && i - start < MaxItemLength)
 162                 continue;
 163
 164             m_items.append(QScriptItem(start, itemAnalysis));
 165             start = i;
 166             itemAnalysis = m_analysis[start];
 167
 168             if (atWordBoundary)
 169                 itemAnalysis.flags = QScriptAnalysis::Uppercase;
 170         }
 171         m_items.append(QScriptItem(start, itemAnalysis));
 172     }
 173
 174     void generateScriptItemsSmallCaps(const ushort *uc, int start, int length)
 175     {
 176         if (!length)
 177             return;
 178         bool lower = (QChar::category(uc[start]) == QChar::Letter_Lowercase);
 179         const int end = start + length;
 180         // split text into parts that are already uppercase and parts that are lowercase, and mark the latter to be uppercased later.
 181         for (int i = start + 1; i < end; ++i) {
 182             bool l = (QChar::category(uc[i]) == QChar::Letter_Lowercase);
 183             if ((m_analysis[i] == m_analysis[start])
 184                 && m_analysis[i].flags < QScriptAnalysis::TabOrObject
 185                 && l == lower
 186                 && i - start < MaxItemLength)
 187                 continue;
 188             m_items.append(QScriptItem(start, m_analysis[start]));
 189             if (lower)
 190                 m_items.last().analysis.flags = QScriptAnalysis::SmallCaps;
 191
 192             start = i;
 193             lower = l;
 194         }
 195         m_items.append(QScriptItem(start, m_analysis[start]));
 196         if (lower)
 197             m_items.last().analysis.flags = QScriptAnalysis::SmallCaps;
 198     }
 199
 200     const QString &m_string;
 201     const QScriptAnalysis * const m_analysis;
 202     QScriptItemArray &m_items;
 203     QTextBoundaryFinder *m_splitter;
 204 };
 205 }
 206
 207
 208 // ----------------------------------------------------------------------------
 209 //
 210 // The BiDi algorithm
 211 //
 212 // ----------------------------------------------------------------------------
 213
 214 #define BIDI_DEBUG 0
 215 #if (BIDI_DEBUG >= 1)
 216 QT_BEGIN_INCLUDE_NAMESPACE
 217 #include <iostream>
 218 QT_END_INCLUDE_NAMESPACE
 219 using namespace std;
 220
 221 static const char *directions[] = {
 222     "DirL", "DirR", "DirEN", "DirES", "DirET", "DirAN", "DirCS", "DirB", "DirS", "DirWS", "DirON",
 223     "DirLRE", "DirLRO", "DirAL", "DirRLE", "DirRLO", "DirPDF", "DirNSM", "DirBN"
 224 };
 225
 226 #endif
 227
 228 struct QBidiStatus {
 229     QBidiStatus() {
 230         eor = QChar::DirON;
 231         lastStrong = QChar::DirON;
 232         last = QChar:: DirON;
 233         dir = QChar::DirON;
 234     }
 235     QChar::Direction eor;
 236     QChar::Direction lastStrong;
 237     QChar::Direction last;
 238     QChar::Direction dir;
 239 };
 240
 241 enum { MaxBidiLevel = 61 };
 242
 243 struct QBidiControl {
 244     inline QBidiControl(bool rtl)
 245         : cCtx(0), base(rtl ? 1 : 0), level(rtl ? 1 : 0), override(false) {}
 246
 247     inline void embed(bool rtl, bool o = false) {
 248         unsigned int toAdd = 1;
 249         if((level%2 != 0) == rtl ) {
 250             ++toAdd;
 251         }
 252         if (level + toAdd <= MaxBidiLevel) {
 253             ctx[cCtx].level = level;
 254             ctx[cCtx].override = override;
 255             cCtx++;
 256             override = o;
 257             level += toAdd;
 258         }
 259     }
 260     inline bool canPop() const { return cCtx != 0; }
 261     inline void pdf() {
 262         Q_ASSERT(cCtx);
 263         --cCtx;
 264         level = ctx[cCtx].level;
 265         override = ctx[cCtx].override;
 266     }
 267
 268     inline QChar::Direction basicDirection() const {
 269         return (base ? QChar::DirR : QChar:: DirL);
 270     }
 271     inline unsigned int baseLevel() const {
 272         return base;
 273     }
 274     inline QChar::Direction direction() const {
 275         return ((level%2) ? QChar::DirR : QChar:: DirL);
 276     }
 277
 278     struct {
 279         unsigned int level;
 280         bool override;
 281     } ctx[MaxBidiLevel];
 282     unsigned int cCtx;
 283     const unsigned int base;
 284     unsigned int level;
 285     bool override;
 286 };
 287
 288
 289 static void appendItems(QScriptAnalysis *analysis, int &start, int &stop, const QBidiControl &control, QChar::Direction dir)
 290 {
 291     if (start > stop)
 292         return;
 293
 294     int level = control.level;
 295
 296     if(dir != QChar::DirON && !control.override) {
 297         // add level of run (cases I1 & I2)
 298         if(level % 2) {
 299             if(dir == QChar::DirL || dir == QChar::DirAN || dir == QChar::DirEN)
 300                 level++;
 301         } else {
 302             if(dir == QChar::DirR)
 303                 level++;
 304             else if(dir == QChar::DirAN || dir == QChar::DirEN)
 305                 level += 2;
 306         }
 307     }
 308
 309 #if (BIDI_DEBUG >= 1)
 310     qDebug("new run: dir=%s from %d, to %d level = %d override=%d", directions[dir], start, stop, level, control.override);
 311 #endif
 312     QScriptAnalysis *s = analysis + start;
 313     const QScriptAnalysis *e = analysis + stop;
 314     while (s <= e) {
 315         s->bidiLevel = level;
 316         ++s;
 317     }
 318     ++stop;
 319     start = stop;
 320 }
 321
 322
 323 // creates the next QScript items.
 324 static bool bidiItemize(QTextEngine *engine, QScriptAnalysis *analysis, QBidiControl &control)
 325 {
 326     bool rightToLeft = (control.basicDirection() == 1);
 327     bool hasBidi = rightToLeft;
 328 #if BIDI_DEBUG >= 2
 329     qDebug() << "bidiItemize: rightToLeft=" << rightToLeft << engine->layoutData->string;
 330 #endif
 331
 332     int sor = 0;
 333     int eor = -1;
 334
 335
 336     int length = engine->layoutData->string.length();
 337
 338     const ushort *unicode = (const ushort *)engine->layoutData->string.unicode();
 339     int current = 0;
 340
 341     QChar::Direction dir = rightToLeft ? QChar::DirR : QChar::DirL;
 342     QBidiStatus status;
 343
 344     QChar::Direction sdir = QChar::direction(*unicode);
 345     if (sdir != QChar::DirL && sdir != QChar::DirR && sdir != QChar::DirEN && sdir != QChar::DirAN)
 346         sdir = QChar::DirON;
 347     else
 348         dir = QChar::DirON;
 349     status.eor = sdir;
 350     status.lastStrong = rightToLeft ? QChar::DirR : QChar::DirL;
 351     status.last = status.lastStrong;
 352     status.dir = sdir;
 353
 354
 355     while (current <= length) {
 356
 357         QChar::Direction dirCurrent;
 358         if (current == (int)length)
 359             dirCurrent = control.basicDirection();
 360         else
 361             dirCurrent = QChar::direction(unicode[current]);
 362
 363 #if (BIDI_DEBUG >= 2)
 364 //         qDebug() << "pos=" << current << " dir=" << directions[dir]
 365 //                  << " current=" << directions[dirCurrent] << " last=" << directions[status.last]
 366 //                  << " eor=" << eor << '/' << directions[status.eor]
 367 //                  << " sor=" << sor << " lastStrong="
 368 //                  << directions[status.lastStrong]
 369 //                  << " level=" << (int)control.level << " override=" << (bool)control.override;
 370 #endif
 371
 372         switch(dirCurrent) {
 373
 374             // embedding and overrides (X1-X9 in the BiDi specs)
 375         case QChar::DirRLE:
 376         case QChar::DirRLO:
 377         case QChar::DirLRE:
 378         case QChar::DirLRO:
 379             {
 380                 bool rtl = (dirCurrent == QChar::DirRLE || dirCurrent == QChar::DirRLO);
 381                 hasBidi |= rtl;
 382                 bool override = (dirCurrent == QChar::DirLRO || dirCurrent == QChar::DirRLO);
 383
 384                 unsigned int level = control.level+1;
 385                 if ((level%2 != 0) == rtl) ++level;
 386                 if(level < MaxBidiLevel) {
 387                     eor = current-1;
 388                     appendItems(analysis, sor, eor, control, dir);
 389                     eor = current;
 390                     control.embed(rtl, override);
 391                     QChar::Direction edir = (rtl ? QChar::DirR : QChar::DirL);
 392                     dir = status.eor = edir;
 393                     status.lastStrong = edir;
 394                 }
 395                 break;
 396             }
 397         case QChar::DirPDF:
 398             {
 399                 if (control.canPop()) {
 400                     if (dir != control.direction()) {
 401                         eor = current-1;
 402                         appendItems(analysis, sor, eor, control, dir);
 403                         dir = control.direction();
 404                     }
 405                     eor = current;
 406                     appendItems(analysis, sor, eor, control, dir);
 407                     control.pdf();
 408                     dir = QChar::DirON; status.eor = QChar::DirON;
 409                     status.last = control.direction();
 410                     if (control.override)
 411                         dir = control.direction();
 412                     else
 413                         dir = QChar::DirON;
 414                     status.lastStrong = control.direction();
 415                 }
 416                 break;
 417             }
 418
 419             // strong types
 420         case QChar::DirL:
 421             if(dir == QChar::DirON)
 422                 dir = QChar::DirL;
 423             switch(status.last)
 424                 {
 425                 case QChar::DirL:
 426                     eor = current; status.eor = QChar::DirL; break;
 427                 case QChar::DirR:
 428                 case QChar::DirAL:
 429                 case QChar::DirEN:
 430                 case QChar::DirAN:
 431                     if (eor >= 0) {
 432                         appendItems(analysis, sor, eor, control, dir);
 433                         dir = eor < length ? QChar::direction(unicode[eor]) : control.basicDirection();
 434                         status.eor = dir;
 435                     } else {
 436                         eor = current; status.eor = dir;
 437                     }
 438                     break;
 439                 case QChar::DirES:
 440                 case QChar::DirET:
 441                 case QChar::DirCS:
 442                 case QChar::DirBN:
 443                 case QChar::DirB:
 444                 case QChar::DirS:
 445                 case QChar::DirWS:
 446                 case QChar::DirON:
 447                     if(dir != QChar::DirL) {
 448                         //last stuff takes embedding dir
 449                         if(control.direction() == QChar::DirR) {
 450                             if(status.eor != QChar::DirR) {
 451                                 // AN or EN
 452                                 appendItems(analysis, sor, eor, control, dir);
 453                                 status.eor = QChar::DirON;
 454                                 dir = QChar::DirR;
 455                             }
 456                             eor = current - 1;
 457                             appendItems(analysis, sor, eor, control, dir);
 458                             dir = eor < length ? QChar::direction(unicode[eor]) : control.basicDirection();
 459                             status.eor = dir;
 460                         } else {
 461                             if(status.eor != QChar::DirL) {
 462                                 appendItems(analysis, sor, eor, control, dir);
 463                                 status.eor = QChar::DirON;
 464                                 dir = QChar::DirL;
 465                             } else {
 466                                 eor = current; status.eor = QChar::DirL; break;
 467                             }
 468                         }
 469                     } else {
 470                         eor = current; status.eor = QChar::DirL;
 471                     }
 472                 default:
 473                     break;
 474                 }
 475             status.lastStrong = QChar::DirL;
 476             break;
 477         case QChar::DirAL:
 478         case QChar::DirR:
 479             hasBidi = true;
 480             if(dir == QChar::DirON) dir = QChar::DirR;
 481             switch(status.last)
 482                 {
 483                 case QChar::DirL:
 484                 case QChar::DirEN:
 485                 case QChar::DirAN:
 486                     if (eor >= 0)
 487                         appendItems(analysis, sor, eor, control, dir);
 488                     // fall through
 489                 case QChar::DirR:
 490                 case QChar::DirAL:
 491                     dir = QChar::DirR; eor = current; status.eor = QChar::DirR; break;
 492                 case QChar::DirES:
 493                 case QChar::DirET:
 494                 case QChar::DirCS:
 495                 case QChar::DirBN:
 496                 case QChar::DirB:
 497                 case QChar::DirS:
 498                 case QChar::DirWS:
 499                 case QChar::DirON:
 500                     if(status.eor != QChar::DirR && status.eor != QChar::DirAL) {
 501                         //last stuff takes embedding dir
 502                         if(control.direction() == QChar::DirR
 503                            || status.lastStrong == QChar::DirR || status.lastStrong == QChar::DirAL) {
 504                             appendItems(analysis, sor, eor, control, dir);
 505                             dir = QChar::DirR; status.eor = QChar::DirON;
 506                             eor = current;
 507                         } else {
 508                             eor = current - 1;
 509                             appendItems(analysis, sor, eor, control, dir);
 510                             dir = QChar::DirR; status.eor = QChar::DirON;
 511                         }
 512                     } else {
 513                         eor = current; status.eor = QChar::DirR;
 514                     }
 515                 default:
 516                     break;
 517                 }
 518             status.lastStrong = dirCurrent;
 519             break;
 520
 521             // weak types:
 522
 523         case QChar::DirNSM:
 524             if (eor == current-1)
 525                 eor = current;
 526             break;
 527         case QChar::DirEN:
 528             // if last strong was AL change EN to AN
 529             if(status.lastStrong != QChar::DirAL) {
 530                 if(dir == QChar::DirON) {
 531                     if(status.lastStrong == QChar::DirL)
 532                         dir = QChar::DirL;
 533                     else
 534                         dir = QChar::DirEN;
 535                 }
 536                 switch(status.last)
 537                     {
 538                     case QChar::DirET:
 539                         if (status.lastStrong == QChar::DirR || status.lastStrong == QChar::DirAL) {
 540                             appendItems(analysis, sor, eor, control, dir);
 541                             status.eor = QChar::DirON;
 542                             dir = QChar::DirAN;
 543                         }
 544                         // fall through
 545                     case QChar::DirEN:
 546                     case QChar::DirL:
 547                         eor = current;
 548                         status.eor = dirCurrent;
 549                         break;
 550                     case QChar::DirR:
 551                     case QChar::DirAL:
 552                     case QChar::DirAN:
 553                         if (eor >= 0)
 554                             appendItems(analysis, sor, eor, control, dir);
 555                         else
 556                             eor = current;
 557                         status.eor = QChar::DirEN;
 558                         dir = QChar::DirAN; break;
 559                     case QChar::DirES:
 560                     case QChar::DirCS:
 561                         if(status.eor == QChar::DirEN || dir == QChar::DirAN) {
 562                             eor = current; break;
 563                         }
 564                     case QChar::DirBN:
 565                     case QChar::DirB:
 566                     case QChar::DirS:
 567                     case QChar::DirWS:
 568                     case QChar::DirON:
 569                         if(status.eor == QChar::DirR) {
 570                             // neutrals go to R
 571                             eor = current - 1;
 572                             appendItems(analysis, sor, eor, control, dir);
 573                             dir = QChar::DirON; status.eor = QChar::DirEN;
 574                             dir = QChar::DirAN;
 575                         }
 576                         else if(status.eor == QChar::DirL ||
 577                                  (status.eor == QChar::DirEN && status.lastStrong == QChar::DirL)) {
 578                             eor = current; status.eor = dirCurrent;
 579                         } else {
 580                             // numbers on both sides, neutrals get right to left direction
 581                             if(dir != QChar::DirL) {
 582                                 appendItems(analysis, sor, eor, control, dir);
 583                                 dir = QChar::DirON; status.eor = QChar::DirON;
 584                                 eor = current - 1;
 585                                 dir = QChar::DirR;
 586                                 appendItems(analysis, sor, eor, control, dir);
 587                                 dir = QChar::DirON; status.eor = QChar::DirON;
 588                                 dir = QChar::DirAN;
 589                             } else {
 590                                 eor = current; status.eor = dirCurrent;
 591                             }
 592                         }
 593                     default:
 594                         break;
 595                     }
 596                 break;
 597             }
 598         case QChar::DirAN:
 599             hasBidi = true;
 600             dirCurrent = QChar::DirAN;
 601             if(dir == QChar::DirON) dir = QChar::DirAN;
 602             switch(status.last)
 603                 {
 604                 case QChar::DirL:
 605                 case QChar::DirAN:
 606                     eor = current; status.eor = QChar::DirAN; break;
 607                 case QChar::DirR:
 608                 case QChar::DirAL:
 609                 case QChar::DirEN:
 610                     if (eor >= 0){
 611                         appendItems(analysis, sor, eor, control, dir);
 612                     } else {
 613                         eor = current;
 614                     }
 615                     dir = QChar::DirAN; status.eor = QChar::DirAN;
 616                     break;
 617                 case QChar::DirCS:
 618                     if(status.eor == QChar::DirAN) {
 619                         eor = current; break;
 620                     }
 621                 case QChar::DirES:
 622                 case QChar::DirET:
 623                 case QChar::DirBN:
 624                 case QChar::DirB:
 625                 case QChar::DirS:
 626                 case QChar::DirWS:
 627                 case QChar::DirON:
 628                     if(status.eor == QChar::DirR) {
 629                         // neutrals go to R
 630                         eor = current - 1;
 631                         appendItems(analysis, sor, eor, control, dir);
 632                         status.eor = QChar::DirAN;
 633                         dir = QChar::DirAN;
 634                     } else if(status.eor == QChar::DirL ||
 635                                (status.eor == QChar::DirEN && status.lastStrong == QChar::DirL)) {
 636                         eor = current; status.eor = dirCurrent;
 637                     } else {
 638                         // numbers on both sides, neutrals get right to left direction
 639                         if(dir != QChar::DirL) {
 640                             appendItems(analysis, sor, eor, control, dir);
 641                             status.eor = QChar::DirON;
 642                             eor = current - 1;
 643                             dir = QChar::DirR;
 644                             appendItems(analysis, sor, eor, control, dir);
 645                             status.eor = QChar::DirAN;
 646                             dir = QChar::DirAN;
 647                         } else {
 648                             eor = current; status.eor = dirCurrent;
 649                         }
 650                     }
 651                 default:
 652                     break;
 653                 }
 654             break;
 655         case QChar::DirES:
 656         case QChar::DirCS:
 657             break;
 658         case QChar::DirET:
 659             if(status.last == QChar::DirEN) {
 660                 dirCurrent = QChar::DirEN;
 661                 eor = current; status.eor = dirCurrent;
 662             }
 663             break;
 664
 665             // boundary neutrals should be ignored
 666         case QChar::DirBN:
 667             break;
 668             // neutrals
 669         case QChar::DirB:
 670             // ### what do we do with newline and paragraph separators that come to here?
 671             break;
 672         case QChar::DirS:
 673             // ### implement rule L1
 674             break;
 675         case QChar::DirWS:
 676         case QChar::DirON:
 677             break;
 678         default:
 679             break;
 680         }
 681
 682         //qDebug() << "     after: dir=" << //        dir << " current=" << dirCurrent << " last=" << status.last << " eor=" << status.eor << " lastStrong=" << status.lastStrong << " embedding=" << control.direction();
 683
 684         if(current >= (int)length) break;
 685
 686         // set status.last as needed.
 687         switch(dirCurrent) {
 688         case QChar::DirET:
 689         case QChar::DirES:
 690         case QChar::DirCS:
 691         case QChar::DirS:
 692         case QChar::DirWS:
 693         case QChar::DirON:
 694             switch(status.last)
 695             {
 696             case QChar::DirL:
 697             case QChar::DirR:
 698             case QChar::DirAL:
 699             case QChar::DirEN:
 700             case QChar::DirAN:
 701                 status.last = dirCurrent;
 702                 break;
 703             default:
 704                 status.last = QChar::DirON;
 705             }
 706             break;
 707         case QChar::DirNSM:
 708         case QChar::DirBN:
 709             // ignore these
 710             break;
 711         case QChar::DirLRO:
 712         case QChar::DirLRE:
 713             status.last = QChar::DirL;
 714             break;
 715         case QChar::DirRLO:
 716         case QChar::DirRLE:
 717             status.last = QChar::DirR;
 718             break;
 719         case QChar::DirEN:
 720             if (status.last == QChar::DirL) {
 721                 status.last = QChar::DirL;
 722                 break;
 723             }
 724             // fall through
 725         default:
 726             status.last = dirCurrent;
 727         }
 728
 729         ++current;
 730     }
 731
 732 #if (BIDI_DEBUG >= 1)
 733     qDebug() << "reached end of line current=" << current << ", eor=" << eor;
 734 #endif
 735     eor = current - 1; // remove dummy char
 736
 737     if (sor <= eor)
 738         appendItems(analysis, sor, eor, control, dir);
 739
 740     return hasBidi;
 741 }
 742
 743 void QTextEngine::bidiReorder(int numItems, const quint8 *levels, int *visualOrder)
 744 {
 745
 746     // first find highest and lowest levels
 747     quint8 levelLow = 128;
 748     quint8 levelHigh = 0;
 749     int i = 0;
 750     while (i < numItems) {
 751         //printf("level = %d\n", r->level);
 752         if (levels[i] > levelHigh)
 753             levelHigh = levels[i];
 754         if (levels[i] < levelLow)
 755             levelLow = levels[i];
 756         i++;
 757     }
 758
 759     // implements reordering of the line (L2 according to BiDi spec):
 760     // L2. From the highest level found in the text to the lowest odd level on each line,
 761     // reverse any contiguous sequence of characters that are at that level or higher.
 762
 763     // reversing is only done up to the lowest odd level
 764     if(!(levelLow%2)) levelLow++;
 765
 766 #if (BIDI_DEBUG >= 1)
 767 //     qDebug() << "reorderLine: lineLow = " << (uint)levelLow << ", lineHigh = " << (uint)levelHigh;
 768 #endif
 769
 770     int count = numItems - 1;
 771     for (i = 0; i < numItems; i++)
 772         visualOrder[i] = i;
 773
 774     while(levelHigh >= levelLow) {
 775         int i = 0;
 776         while (i < count) {
 777             while(i < count && levels[i] < levelHigh) i++;
 778             int start = i;
 779             while(i <= count && levels[i] >= levelHigh) i++;
 780             int end = i-1;
 781
 782             if(start != end) {
 783                 //qDebug() << "reversing from " << start << " to " << end;
 784                 for(int j = 0; j < (end-start+1)/2; j++) {
 785                     int tmp = visualOrder[start+j];
 786                     visualOrder[start+j] = visualOrder[end-j];
 787                     visualOrder[end-j] = tmp;
 788                 }
 789             }
 790             i++;
 791         }
 792         levelHigh--;
 793     }
 794
 795 #if (BIDI_DEBUG >= 1)
 796 //     qDebug() << "visual order is:";
 797 //     for (i = 0; i < numItems; i++)
 798 //         qDebug() << visualOrder[i];
 799 #endif
 800 }
 801
 802 QT_BEGIN_INCLUDE_NAMESPACE
 803
 804 #if defined(Q_WS_X11) || defined (Q_WS_QWS)
 805 #   include "qfontengine_ft_p.h"
 806 #elif defined(Q_WS_MAC)
 807 # include "qtextengine_mac.cpp"
 808 #endif
 809
 810 #include <private/qharfbuzz_p.h>
 811
 812 QT_END_INCLUDE_NAMESPACE
 813
 814 // ask the font engine to find out which glyphs (as an index in the specific font) to use for the text in one item.
 815 static bool stringToGlyphs(HB_ShaperItem *item, QGlyphLayout *glyphs, QFontEngine *fontEngine)
 816 {
 817     int nGlyphs = item->num_glyphs;
 818
 819     QTextEngine::ShaperFlags shaperFlags(QTextEngine::GlyphIndicesOnly);
 820     if (item->item.bidiLevel % 2)
 821         shaperFlags |= QTextEngine::RightToLeft;
 822
 823     bool result = fontEngine->stringToCMap(reinterpret_cast<const QChar *>(item->string + item->item.pos), item->item.length, glyphs, &nGlyphs, shaperFlags);
 824     item->num_glyphs = nGlyphs;
 825     glyphs->numGlyphs = nGlyphs;
 826     return result;
 827 }
 828
 829 // shape all the items that intersect with the line, taking tab widths into account to find out what text actually fits in the line.
 830 void QTextEngine::shapeLine(const QScriptLine &line)
 831 {
 832     QFixed x;
 833     bool first = true;
 834     const int end = findItem(line.from + line.length - 1);
 835     int item = findItem(line.from);
 836     if (item == -1)
 837         return;
 838     for (item = findItem(line.from); item <= end; ++item) {
 839         QScriptItem &si = layoutData->items[item];
 840         if (si.analysis.flags == QScriptAnalysis::Tab) {
 841             ensureSpace(1);
 842             si.width = calculateTabWidth(item, x);
 843         } else {
 844             shape(item);
 845         }
 846         if (first && si.position != line.from) { // that means our x position has to be offset
 847             QGlyphLayout glyphs = shapedGlyphs(&si);
 848             Q_ASSERT(line.from > si.position);
 849             for (int i = line.from - si.position - 1; i >= 0; i--) {
 850                 x -= glyphs.effectiveAdvance(i);
 851             }
 852         }
 853         first = false;
 854
 855         x += si.width;
 856     }
 857 }
 858
 859 void QTextEngine::shapeText(int item) const
 860 {
 861     Q_ASSERT(item < layoutData->items.size());
 862     QScriptItem &si = layoutData->items[item];
 863
 864     if (si.num_glyphs)
 865         return;
 866
 867 #if defined(Q_WS_MAC)
 868     shapeTextMac(item);
 869 #elif defined(Q_WS_WINCE)
 870     shapeTextWithCE(item);
 871 #else
 872     shapeTextWithHarfbuzz(item);
 873 #endif
 874
 875     si.width = 0;
 876
 877     if (!si.num_glyphs)
 878         return;
 879     QGlyphLayout glyphs = shapedGlyphs(&si);
 880
 881     QFont font = this->font(si);
 882     bool letterSpacingIsAbsolute = font.d->letterSpacingIsAbsolute;
 883     QFixed letterSpacing = font.d->letterSpacing;
 884     QFixed wordSpacing = font.d->wordSpacing;
 885
 886     if (letterSpacingIsAbsolute && letterSpacing.value())
 887         letterSpacing *= font.d->dpi / qt_defaultDpiY();
 888
 889     if (letterSpacing != 0) {
 890         for (int i = 1; i < si.num_glyphs; ++i) {
 891             if (glyphs.attributes[i].clusterStart) {
 892                 if (letterSpacingIsAbsolute)
 893                     glyphs.advances_x[i-1] += letterSpacing;
 894                 else {
 895                     QFixed &advance = glyphs.advances_x[i-1];
 896                     advance += (letterSpacing - 100) * advance / 100;
 897                 }
 898             }
 899         }
 900         if (letterSpacingIsAbsolute)
 901             glyphs.advances_x[si.num_glyphs-1] += letterSpacing;
 902         else {
 903             QFixed &advance = glyphs.advances_x[si.num_glyphs-1];
 904             advance += (letterSpacing - 100) * advance / 100;
 905         }
 906     }
 907     if (wordSpacing != 0) {
 908         for (int i = 0; i < si.num_glyphs; ++i) {
 909             if (glyphs.attributes[i].justification == HB_Space
 910                 || glyphs.attributes[i].justification == HB_Arabic_Space) {
 911                 // word spacing only gets added once to a consecutive run of spaces (see CSS spec)
 912                 if (i + 1 == si.num_glyphs
 913                     ||(glyphs.attributes[i+1].justification != HB_Space
 914                        && glyphs.attributes[i+1].justification != HB_Arabic_Space))
 915                     glyphs.advances_x[i] += wordSpacing;
 916             }
 917         }
 918     }
 919
 920     for (int i = 0; i < si.num_glyphs; ++i)
 921         si.width += glyphs.advances_x[i];
 922 }
 923
 924 static inline bool hasCaseChange(const QScriptItem &si)
 925 {
 926     return si.analysis.flags == QScriptAnalysis::SmallCaps ||
 927            si.analysis.flags == QScriptAnalysis::Uppercase ||
 928            si.analysis.flags == QScriptAnalysis::Lowercase;
 929 }
 930
 931 #if defined(Q_WS_WINCE) //TODO
 932 // set the glyph attributes heuristically. Assumes a 1 to 1 relationship between chars and glyphs
 933 // and no reordering.
 934 // also computes logClusters heuristically
 935 static void heuristicSetGlyphAttributes(const QChar *uc, int length, QGlyphLayout *glyphs, unsigned short *logClusters, int num_glyphs)
 936 {
 937     // ### zeroWidth and justification are missing here!!!!!
 938
 939     Q_UNUSED(num_glyphs);
 940     Q_ASSERT(num_glyphs <= length);
 941
 942 //     qDebug("QScriptEngine::heuristicSetGlyphAttributes, num_glyphs=%d", item->num_glyphs);
 943
 944     int glyph_pos = 0;
 945     for (int i = 0; i < length; i++) {
 946         if (uc[i].unicode() >= 0xd800 && uc[i].unicode() < 0xdc00 && i < length-1
 947             && uc[i+1].unicode() >= 0xdc00 && uc[i+1].unicode() < 0xe000) {
 948             logClusters[i] = glyph_pos;
 949             logClusters[++i] = glyph_pos;
 950         } else {
 951             logClusters[i] = glyph_pos;
 952         }
 953         ++glyph_pos;
 954     }
 955
 956     // first char in a run is never (treated as) a mark
 957     int cStart = 0;
 958
 959     const bool symbolFont = false; // ####
 960     glyphs->attributes[0].mark = false;
 961     glyphs->attributes[0].clusterStart = true;
 962     glyphs->attributes[0].dontPrint = (!symbolFont && uc[0].unicode() == 0x00ad) || qIsControlChar(uc[0].unicode());
 963
 964     int pos = 0;
 965     int lastCat = QChar::category(uc[0].unicode());
 966     for (int i = 1; i < length; ++i) {
 967         if (logClusters[i] == pos)
 968             // same glyph
 969             continue;
 970         ++pos;
 971         while (pos < logClusters[i]) {
 972             glyphs[pos].attributes = glyphs[pos-1].attributes;
 973             ++pos;
 974         }
 975         // hide soft-hyphens by default
 976         if ((!symbolFont && uc[i].unicode() == 0x00ad) || qIsControlChar(uc[i].unicode()))
 977             glyphs->attributes[pos].dontPrint = true;
 978         const QUnicodeTables::Properties *prop = QUnicodeTables::properties(uc[i].unicode());
 979         int cat = prop->category;
 980         if (cat != QChar::Mark_NonSpacing) {
 981             glyphs->attributes[pos].mark = false;
 982             glyphs->attributes[pos].clusterStart = true;
 983             glyphs->attributes[pos].combiningClass = 0;
 984             cStart = logClusters[i];
 985         } else {
 986             int cmb = prop->combiningClass;
 987
 988             if (cmb == 0) {
 989                 // Fix 0 combining classes
 990                 if ((uc[pos].unicode() & 0xff00) == 0x0e00) {
 991                     // thai or lao
 992                     unsigned char col = uc[pos].cell();
 993                     if (col == 0x31 ||
 994                          col == 0x34 ||
 995                          col == 0x35 ||
 996                          col == 0x36 ||
 997                          col == 0x37 ||
 998                          col == 0x47 ||
 999                          col == 0x4c ||
1000                          col == 0x4d ||
1001                          col == 0x4e) {
1002                         cmb = QChar::Combining_AboveRight;
1003                     } else if (col == 0xb1 ||
1004                                 col == 0xb4 ||
1005                                 col == 0xb5 ||
1006                                 col == 0xb6 ||
1007                                 col == 0xb7 ||
1008                                 col == 0xbb ||
1009                                 col == 0xcc ||
1010                                 col == 0xcd) {
1011                         cmb = QChar::Combining_Above;
1012                     } else if (col == 0xbc) {
1013                         cmb = QChar::Combining_Below;
1014                     }
1015                 }
1016             }
1017
1018             glyphs->attributes[pos].mark = true;
1019             glyphs->attributes[pos].clusterStart = false;
1020             glyphs->attributes[pos].combiningClass = cmb;
1021             logClusters[i] = cStart;
1022             glyphs->advances_x[pos] = 0;
1023             glyphs->advances_y[pos] = 0;
1024         }
1025
1026         // one gets an inter character justification point if the current char is not a non spacing mark.
1027         // as then the current char belongs to the last one and one gets a space justification point
1028         // after the space char.
1029         if (lastCat == QChar::Separator_Space)
1030             glyphs->attributes[pos-1].justification = HB_Space;
1031         else if (cat != QChar::Mark_NonSpacing)
1032             glyphs->attributes[pos-1].justification = HB_Character;
1033         else
1034             glyphs->attributes[pos-1].justification = HB_NoJustification;
1035
1036         lastCat = cat;
1037     }
1038     pos = logClusters[length-1];
1039     if (lastCat == QChar::Separator_Space)
1040         glyphs->attributes[pos].justification = HB_Space;
1041     else
1042         glyphs->attributes[pos].justification = HB_Character;
1043 }
1044
1045 void QTextEngine::shapeTextWithCE(int item) const
1046 {
1047     QScriptItem &si = layoutData->items[item];
1048     si.glyph_data_offset = layoutData->used;
1049
1050     QFontEngine *fe = fontEngine(si, &si.ascent, &si.descent, &si.leading);
1051
1052     QTextEngine::ShaperFlags flags;
1053     if (si.analysis.bidiLevel % 2)
1054         flags |= RightToLeft;
1055     if (option.useDesignMetrics())
1056         flags |= DesignMetrics;
1057
1058     // pre-initialize char attributes
1059     if (! attributes())
1060         return;
1061
1062     const int len = length(item);
1063     int num_glyphs = length(item);
1064     const QChar *str = layoutData->string.unicode() + si.position;
1065     ushort upperCased[256];
1066     if (hasCaseChange(si)) {
1067         ushort *uc = upperCased;
1068         if (len > 256)
1069             uc = new ushort[len];
1070         for (int i = 0; i < len; ++i) {
1071             if(si.analysis.flags == QScriptAnalysis::Lowercase)
1072                 uc[i] = str[i].toLower().unicode();
1073             else
1074                 uc[i] = str[i].toUpper().unicode();
1075         }
1076         str = reinterpret_cast<const QChar *>(uc);
1077     }
1078
1079     while (true) {
1080         if (! ensureSpace(num_glyphs)) {
1081             // If str is converted to uppercase/lowercase form with a new buffer,
1082             // we need to delete that buffer before return for error
1083             const ushort *uc = reinterpret_cast<const ushort *>(str);
1084             if (hasCaseChange(si) && uc != upperCased)
1085                 delete [] uc;
1086             return;
1087         }
1088         num_glyphs = layoutData->glyphLayout.numGlyphs - layoutData->used;
1089
1090         QGlyphLayout g = availableGlyphs(&si);
1091         unsigned short *log_clusters = logClusters(&si);
1092
1093         if (fe->stringToCMap(str,
1094                              len,
1095                              &g,
1096                              &num_glyphs,
1097                              flags)) {
1098             heuristicSetGlyphAttributes(str, len, &g, log_clusters, num_glyphs);
1099                     break;
1100         }
1101     }
1102
1103     si.num_glyphs = num_glyphs;
1104
1105     layoutData->used += si.num_glyphs;
1106
1107     const ushort *uc = reinterpret_cast<const ushort *>(str);
1108     if (hasCaseChange(si) && uc != upperCased)
1109         delete [] uc;
1110 }
1111 #endif
1112
1113 static inline void moveGlyphData(const QGlyphLayout &destination, const QGlyphLayout &source, int num)
1114 {
1115     if (num > 0 && destination.glyphs != source.glyphs) {
1116         memmove(destination.glyphs, source.glyphs, num * sizeof(HB_Glyph));
1117         memmove(destination.attributes, source.attributes, num * sizeof(HB_GlyphAttributes));
1118         memmove(destination.advances_x, source.advances_x, num * sizeof(HB_Fixed));
1119         memmove(destination.offsets, source.offsets, num * sizeof(HB_FixedPoint));
1120     }
1121 }
1122
1123 /// take the item from layoutData->items and
1124 void QTextEngine::shapeTextWithHarfbuzz(int item) const
1125 {
1126     Q_ASSERT(sizeof(HB_Fixed) == sizeof(QFixed));
1127     Q_ASSERT(sizeof(HB_FixedPoint) == sizeof(QFixedPoint));
1128
1129     QScriptItem &si = layoutData->items[item];
1130
1131     si.glyph_data_offset = layoutData->used;
1132
1133     QFontEngine *font = fontEngine(si, &si.ascent, &si.descent, &si.leading);
1134
1135     bool kerningEnabled = this->font(si).d->kerning;
1136
1137     HB_ShaperItem entire_shaper_item;
1138     qMemSet(&entire_shaper_item, 0, sizeof(entire_shaper_item));
1139     entire_shaper_item.string = reinterpret_cast<const HB_UChar16 *>(layoutData->string.constData());
1140     entire_shaper_item.stringLength = layoutData->string.length();
1141     entire_shaper_item.item.script = (HB_Script)si.analysis.script;
1142     entire_shaper_item.item.pos = si.position;
1143     entire_shaper_item.item.length = length(item);
1144     entire_shaper_item.item.bidiLevel = si.analysis.bidiLevel;
1145
1146     HB_UChar16 upperCased[256]; // XXX what about making this 4096, so we don't have to extend it ever.
1147     if (hasCaseChange(si)) {
1148         HB_UChar16 *uc = upperCased;
1149         if (entire_shaper_item.item.length > 256)
1150             uc = new HB_UChar16[entire_shaper_item.item.length];
1151         for (uint i = 0; i < entire_shaper_item.item.length; ++i) {
1152             if(si.analysis.flags == QScriptAnalysis::Lowercase)
1153                 uc[i] = QChar::toLower(entire_shaper_item.string[si.position + i]);
1154             else
1155                 uc[i] = QChar::toUpper(entire_shaper_item.string[si.position + i]);
1156         }
1157         entire_shaper_item.item.pos = 0;
1158         entire_shaper_item.string = uc;
1159         entire_shaper_item.stringLength = entire_shaper_item.item.length;
1160     }
1161
1162     entire_shaper_item.shaperFlags = 0;
1163     if (!kerningEnabled)
1164         entire_shaper_item.shaperFlags |= HB_ShaperFlag_NoKerning;
1165     if (option.useDesignMetrics())
1166         entire_shaper_item.shaperFlags |= HB_ShaperFlag_UseDesignMetrics;
1167
1168     entire_shaper_item.num_glyphs = qMax(layoutData->glyphLayout.numGlyphs - layoutData->used, int(entire_shaper_item.item.length));
1169     if (! ensureSpace(entire_shaper_item.num_glyphs)) {
1170         if (hasCaseChange(si))
1171             delete [] const_cast<HB_UChar16 *>(entire_shaper_item.string);
1172         return;
1173     }
1174     QGlyphLayout initialGlyphs = availableGlyphs(&si).mid(0, entire_shaper_item.num_glyphs);
1175
1176     if (!stringToGlyphs(&entire_shaper_item, &initialGlyphs, font)) {
1177         if (! ensureSpace(entire_shaper_item.num_glyphs)) {
1178             if (hasCaseChange(si))
1179                 delete [] const_cast<HB_UChar16 *>(entire_shaper_item.string);
1180             return;
1181         }
1182         initialGlyphs = availableGlyphs(&si).mid(0, entire_shaper_item.num_glyphs);
1183
1184         if (!stringToGlyphs(&entire_shaper_item, &initialGlyphs, font)) {
1185             // ############ if this happens there's a bug in the fontengine
1186             if (hasCaseChange(si) && entire_shaper_item.string != upperCased)
1187                 delete [] const_cast<HB_UChar16 *>(entire_shaper_item.string);
1188             return;
1189         }
1190     }
1191
1192     // split up the item into parts that come from different font engines.
1193     QVarLengthArray<int> itemBoundaries(2);
1194     // k * 2 entries, array[k] == index in string, array[k + 1] == index in glyphs
1195     itemBoundaries[0] = entire_shaper_item.item.pos;
1196     itemBoundaries[1] = 0;
1197
1198     if (font->type() == QFontEngine::Multi) {
1199         uint lastEngine = 0;
1200         int charIdx = entire_shaper_item.item.pos;
1201         const int stringEnd = charIdx + entire_shaper_item.item.length;
1202         for (quint32 i = 0; i < entire_shaper_item.num_glyphs; ++i, ++charIdx) {
1203             uint engineIdx = initialGlyphs.glyphs[i] >> 24;
1204             if (engineIdx != lastEngine && i > 0) {
1205                 itemBoundaries.append(charIdx);
1206                 itemBoundaries.append(i);
1207             }
1208             lastEngine = engineIdx;
1209             if (HB_IsHighSurrogate(entire_shaper_item.string[charIdx])
1210                 && charIdx < stringEnd - 1
1211                 && HB_IsLowSurrogate(entire_shaper_item.string[charIdx + 1]))
1212                 ++charIdx;
1213         }
1214     }
1215
1216
1217
1218     int remaining_glyphs = entire_shaper_item.num_glyphs;
1219     int glyph_pos = 0;
1220     // for each item shape using harfbuzz and store the results in our layoutData's glyphs array.
1221     for (int k = 0; k < itemBoundaries.size(); k += 2) { // for the +2, see the comment at the definition of itemBoundaries
1222
1223         HB_ShaperItem shaper_item = entire_shaper_item;
1224
1225         shaper_item.item.pos = itemBoundaries[k];
1226         if (k < itemBoundaries.size() - 3) {
1227             shaper_item.item.length = itemBoundaries[k + 2] - shaper_item.item.pos;
1228             shaper_item.num_glyphs = itemBoundaries[k + 3] - itemBoundaries[k + 1];
1229         } else { // last combo in the list, avoid out of bounds access.
1230             shaper_item.item.length -= shaper_item.item.pos - entire_shaper_item.item.pos;
1231             shaper_item.num_glyphs -= itemBoundaries[k + 1];
1232         }
1233         shaper_item.initialGlyphCount = shaper_item.num_glyphs;
1234         if (shaper_item.num_glyphs < shaper_item.item.length)
1235             shaper_item.num_glyphs = shaper_item.item.length;
1236
1237         QFontEngine *actualFontEngine = font;
1238         uint engineIdx = 0;
1239         if (font->type() == QFontEngine::Multi) {
1240             engineIdx = uint(availableGlyphs(&si).glyphs[glyph_pos] >> 24);
1241
1242             actualFontEngine = static_cast<QFontEngineMulti *>(font)->engine(engineIdx);
1243         }
1244
1245         shaper_item.font = actualFontEngine->harfbuzzFont();
1246         shaper_item.face = actualFontEngine->harfbuzzFace();
1247
1248         shaper_item.glyphIndicesPresent = true;
1249
1250         remaining_glyphs -= shaper_item.initialGlyphCount;
1251
1252         do {
1253             if (! ensureSpace(glyph_pos + shaper_item.num_glyphs + remaining_glyphs)) {
1254                 if (hasCaseChange(si))
1255                     delete [] const_cast<HB_UChar16 *>(entire_shaper_item.string);
1256                 return;
1257             }
1258
1259             const QGlyphLayout g = availableGlyphs(&si).mid(glyph_pos);
1260             if (shaper_item.num_glyphs > shaper_item.item.length)
1261                 moveGlyphData(g.mid(shaper_item.num_glyphs), g.mid(shaper_item.initialGlyphCount), remaining_glyphs);
1262
1263             shaper_item.glyphs = g.glyphs;
1264             shaper_item.attributes = g.attributes;
1265             shaper_item.advances = reinterpret_cast<HB_Fixed *>(g.advances_x);
1266             shaper_item.offsets = reinterpret_cast<HB_FixedPoint *>(g.offsets);
1267
1268             if (shaper_item.glyphIndicesPresent) {
1269                 for (hb_uint32 i = 0; i < shaper_item.initialGlyphCount; ++i)
1270                     shaper_item.glyphs[i] &= 0x00ffffff;
1271             }
1272
1273             shaper_item.log_clusters = logClusters(&si) + shaper_item.item.pos - entire_shaper_item.item.pos;
1274
1275 //          qDebug("    .. num_glyphs=%d, used=%d, item.num_glyphs=%d", num_glyphs, used, shaper_item.num_glyphs);
1276         } while (!qShapeItem(&shaper_item)); // this does the actual shaping via harfbuzz.
1277
1278         QGlyphLayout g = availableGlyphs(&si).mid(glyph_pos, shaper_item.num_glyphs);
1279         moveGlyphData(g.mid(shaper_item.num_glyphs), g.mid(shaper_item.initialGlyphCount), remaining_glyphs);
1280
1281         for (hb_uint32 i = 0; i < shaper_item.num_glyphs; ++i)
1282             g.glyphs[i] = g.glyphs[i] | (engineIdx << 24);
1283
1284         for (hb_uint32 i = 0; i < shaper_item.item.length; ++i)
1285             shaper_item.log_clusters[i] += glyph_pos;
1286
1287         if (kerningEnabled && !shaper_item.kerning_applied)
1288             font->doKerning(&g, option.useDesignMetrics() ? QFlag(QTextEngine::DesignMetrics) : QFlag(0));
1289
1290         glyph_pos += shaper_item.num_glyphs;
1291     }
1292
1293 //     qDebug("    -> item: script=%d num_glyphs=%d", shaper_item.script, shaper_item.num_glyphs);
1294     si.num_glyphs = glyph_pos;
1295
1296     layoutData->used += si.num_glyphs;
1297
1298     if (hasCaseChange(si) && entire_shaper_item.string != upperCased)
1299         delete [] const_cast<HB_UChar16 *>(entire_shaper_item.string);
1300 }
1301
1302 static void init(QTextEngine *e)
1303 {
1304     e->ignoreBidi = false;
1305     e->cacheGlyphs = false;
1306     e->forceJustification = false;
1307
1308     e->layoutData = 0;
1309
1310     e->minWidth = 0;
1311     e->maxWidth = 0;
1312
1313     e->underlinePositions = 0;
1314     e->specialData = 0;
1315     e->stackEngine = false;
1316 }
1317
1318 QTextEngine::QTextEngine()
1319 {
1320     init(this);
1321 }
1322
1323 QTextEngine::QTextEngine(const QString &str, const QFont &f)
1324     : text(str),
1325       fnt(f)
1326 {
1327     init(this);
1328 }
1329
1330 QTextEngine::~QTextEngine()
1331 {
1332     if (!stackEngine)
1333         delete layoutData;
1334     delete specialData;
1335 }
1336
1337 const HB_CharAttributes *QTextEngine::attributes() const
1338 {
1339     if (layoutData && layoutData->haveCharAttributes)
1340         return (HB_CharAttributes *) layoutData->memory;
1341
1342     itemize();
1343     if (! ensureSpace(layoutData->string.length()))
1344         return NULL;
1345
1346     QVarLengthArray<HB_ScriptItem> hbScriptItems(layoutData->items.size());
1347
1348     for (int i = 0; i < layoutData->items.size(); ++i) {
1349         const QScriptItem &si = layoutData->items[i];
1350         hbScriptItems[i].pos = si.position;
1351         hbScriptItems[i].length = length(i);
1352         hbScriptItems[i].bidiLevel = si.analysis.bidiLevel;
1353         hbScriptItems[i].script = (HB_Script)si.analysis.script;
1354     }
1355
1356     qGetCharAttributes(reinterpret_cast<const HB_UChar16 *>(layoutData->string.constData()),
1357                        layoutData->string.length(),
1358                        hbScriptItems.data(), hbScriptItems.size(),
1359                        (HB_CharAttributes *)layoutData->memory);
1360
1361
1362     layoutData->haveCharAttributes = true;
1363     return (HB_CharAttributes *) layoutData->memory;
1364 }
1365
1366 void QTextEngine::shape(int item) const
1367 {
1368     if (layoutData->items[item].analysis.flags == QScriptAnalysis::Object) {
1369         ensureSpace(1);
1370         if (block.docHandle()) {
1371             QTextFormat format = formats()->format(formatIndex(&layoutData->items[item]));
1372             docLayout()->resizeInlineObject(QTextInlineObject(item, const_cast<QTextEngine *>(this)),
1373                                             layoutData->items[item].position + block.position(), format);
1374         }
1375     } else if (layoutData->items[item].analysis.flags == QScriptAnalysis::Tab) {
1376         // set up at least the ascent/descent/leading of the script item for the tab
1377         fontEngine(layoutData->items[item],
1378                    &layoutData->items[item].ascent,
1379                    &layoutData->items[item].descent,
1380                    &layoutData->items[item].leading);
1381     } else {
1382         shapeText(item);
1383     }
1384 }
1385
1386 static inline void releaseCachedFontEngine(QFontEngine *fontEngine)
1387 {
1388     if (fontEngine) {
1389         fontEngine->ref.deref();
1390         if (fontEngine->cache_count == 0 && fontEngine->ref == 0)
1391             delete fontEngine;
1392     }
1393 }
1394
1395 void QTextEngine::invalidate()
1396 {
1397     freeMemory();
1398     minWidth = 0;
1399     maxWidth = 0;
1400     if (specialData)
1401         specialData->resolvedFormatIndices.clear();
1402
1403     releaseCachedFontEngine(feCache.prevFontEngine);
1404     releaseCachedFontEngine(feCache.prevScaledFontEngine);
1405     feCache.reset();
1406 }
1407
1408 void QTextEngine::clearLineData()
1409 {
1410     lines.clear();
1411 }
1412
1413 void QTextEngine::validate() const
1414 {
1415     if (layoutData)
1416         return;
1417     layoutData = new LayoutData();
1418     if (block.docHandle()) {
1419         layoutData->string = block.text();
1420         if (option.flags() & QTextOption::ShowLineAndParagraphSeparators)
1421             layoutData->string += QLatin1Char(block.next().isValid() ? 0xb6 : 0x20);
1422     } else {
1423         layoutData->string = text;
1424     }
1425     if (specialData && specialData->preeditPosition != -1)
1426         layoutData->string.insert(specialData->preeditPosition, specialData->preeditText);
1427 }
1428
1429 void QTextEngine::itemize() const
1430 {
1431     validate();
1432     if (layoutData->items.size())
1433         return;
1434
1435     int length = layoutData->string.length();
1436     if (!length)
1437         return;
1438 #if defined(Q_WS_MAC) && !defined(QT_MAC_USE_COCOA)
1439     // ATSUI requires RTL flags to correctly identify the character stops.
1440     bool ignore = false;
1441 #else
1442     bool ignore = ignoreBidi;
1443 #endif
1444
1445     bool rtl = isRightToLeft();
1446
1447     if (!ignore && !rtl) {
1448         ignore = true;
1449         const QChar *start = layoutData->string.unicode();
1450         const QChar * const end = start + length;
1451         while (start < end) {
1452             if (start->unicode() >= 0x590) {
1453                 ignore = false;
1454                 break;
1455             }
1456             ++start;
1457         }
1458     }
1459
1460     QVarLengthArray<QScriptAnalysis, 4096> scriptAnalysis(length);
1461     QScriptAnalysis *analysis = scriptAnalysis.data();
1462
1463     QBidiControl control(rtl);
1464
1465     if (ignore) {
1466         memset(analysis, 0, length*sizeof(QScriptAnalysis));
1467         if (option.textDirection() == Qt::RightToLeft) {
1468             for (int i = 0; i < length; ++i)
1469                 analysis[i].bidiLevel = 1;
1470             layoutData->hasBidi = true;
1471         }
1472     } else {
1473         layoutData->hasBidi = bidiItemize(const_cast<QTextEngine *>(this), analysis, control);
1474     }
1475
1476     const ushort *uc = reinterpret_cast<const ushort *>(layoutData->string.unicode());
1477     const ushort *e = uc + length;
1478     int lastScript = QUnicodeTables::Common;
1479     while (uc < e) {
1480         int script = QUnicodeTables::script(*uc);
1481         if (script == QUnicodeTables::Inherited)
1482             script = lastScript;
1483         analysis->flags = QScriptAnalysis::None;
1484         if (*uc == QChar::ObjectReplacementCharacter) {
1485             if (analysis->bidiLevel % 2)
1486                 --analysis->bidiLevel;
1487             analysis->script = QUnicodeTables::Common;
1488             analysis->flags = QScriptAnalysis::Object;
1489         } else if (*uc == QChar::LineSeparator) {
1490             if (analysis->bidiLevel % 2)
1491                 --analysis->bidiLevel;
1492             analysis->script = QUnicodeTables::Common;
1493             analysis->flags = QScriptAnalysis::LineOrParagraphSeparator;
1494             if (option.flags() & QTextOption::ShowLineAndParagraphSeparators)
1495                 *const_cast<ushort*>(uc) = 0x21B5; // visual line separator
1496         } else if (*uc == 9) {
1497             analysis->script = QUnicodeTables::Common;
1498             analysis->flags = QScriptAnalysis::Tab;
1499             analysis->bidiLevel = control.baseLevel();
1500         } else if ((*uc == 32 || *uc == QChar::Nbsp)
1501                    && (option.flags() & QTextOption::ShowTabsAndSpaces)) {
1502             analysis->script = QUnicodeTables::Common;
1503             analysis->flags = QScriptAnalysis::Space;
1504             analysis->bidiLevel = control.baseLevel();
1505         } else {
1506             analysis->script = script;
1507         }
1508         lastScript = analysis->script;
1509         ++uc;
1510         ++analysis;
1511     }
1512     if (option.flags() & QTextOption::ShowLineAndParagraphSeparators) {
1513         (analysis-1)->flags = QScriptAnalysis::LineOrParagraphSeparator; // to exclude it from width
1514     }
1515
1516     Itemizer itemizer(layoutData->string, scriptAnalysis.data(), layoutData->items);
1517
1518     const QTextDocumentPrivate *p = block.docHandle();
1519     if (p) {
1520         SpecialData *s = specialData;
1521
1522         QTextDocumentPrivate::FragmentIterator it = p->find(block.position());
1523         QTextDocumentPrivate::FragmentIterator end = p->find(block.position() + block.length() - 1); // -1 to omit the block separator char
1524         int format = it.value()->format;
1525
1526         int prevPosition = 0;
1527         int position = prevPosition;
1528         while (1) {
1529             const QTextFragmentData * const frag = it.value();
1530             if (it == end || format != frag->format) {
1531                 if (s && position >= s->preeditPosition) {
1532                     position += s->preeditText.length();
1533                     s = 0;
1534                 }
1535                 Q_ASSERT(position <= length);
1536                 itemizer.generate(prevPosition, position - prevPosition,
1537                     formats()->charFormat(format).fontCapitalization());
1538                 if (it == end) {
1539                     if (position < length)
1540                         itemizer.generate(position, length - position,
1541                                           formats()->charFormat(format).fontCapitalization());
1542                     break;
1543                 }
1544                 format = frag->format;
1545                 prevPosition = position;
1546             }
1547             position += frag->size_array[0];
1548             ++it;
1549         }
1550     } else {
1551         itemizer.generate(0, length, static_cast<QFont::Capitalization> (fnt.d->capital));
1552     }
1553
1554     addRequiredBoundaries();
1555     resolveAdditionalFormats();
1556 }
1557
1558 bool QTextEngine::isRightToLeft() const
1559 {
1560     switch (option.textDirection()) {
1561     case Qt::LeftToRight:
1562         return false;
1563     case Qt::RightToLeft:
1564         return true;
1565     default:
1566         break;
1567     }
1568     // this places the cursor in the right position depending on the keyboard layout
1569     if (layoutData->string.isEmpty())
1570         return QApplication::keyboardInputDirection() == Qt::RightToLeft;
1571     return layoutData->string.isRightToLeft();
1572 }
1573
1574
1575 int QTextEngine::findItem(int strPos) const
1576 {
1577     itemize();
1578     int left = 0;
1579     int right = layoutData->items.size()-1;
1580     while(left <= right) {
1581         int middle = ((right-left)/2)+left;
1582         if (strPos > layoutData->items[middle].position)
1583             left = middle+1;
1584         else if(strPos < layoutData->items[middle].position)
1585             right = middle-1;
1586         else {
1587             return middle;
1588         }
1589     }
1590     return right;
1591 }
1592
1593 QFixed QTextEngine::width(int from, int len) const
1594 {
1595     itemize();
1596
1597     QFixed w = 0;
1598
1599 //     qDebug("QTextEngine::width(from = %d, len = %d), numItems=%d, strleng=%d", from,  len, items.size(), string.length());
1600     for (int i = 0; i < layoutData->items.size(); i++) {
1601         const QScriptItem *si = layoutData->items.constData() + i;
1602         int pos = si->position;
1603         int ilen = length(i);
1604 //          qDebug("item %d: from %d len %d", i, pos, ilen);
1605         if (pos >= from + len)
1606             break;
1607         if (pos + ilen > from) {
1608             if (!si->num_glyphs)
1609                 shape(i);
1610
1611             if (si->analysis.flags == QScriptAnalysis::Object) {
1612                 w += si->width;
1613                 continue;
1614             } else if (si->analysis.flags == QScriptAnalysis::Tab) {
1615                 w += calculateTabWidth(i, w);
1616                 continue;
1617             }
1618
1619
1620             QGlyphLayout glyphs = shapedGlyphs(si);
1621             unsigned short *logClusters = this->logClusters(si);
1622
1623 //             fprintf(stderr, "  logclusters:");
1624 //             for (int k = 0; k < ilen; k++)
1625 //                 fprintf(stderr, " %d", logClusters[k]);
1626 //             fprintf(stderr, "\n");
1627             // do the simple thing for now and give the first glyph in a cluster the full width, all other ones 0.
1628             int charFrom = from - pos;
1629             if (charFrom < 0)
1630                 charFrom = 0;
1631             int glyphStart = logClusters[charFrom];
1632             if (charFrom > 0 && logClusters[charFrom-1] == glyphStart)
1633                 while (charFrom < ilen && logClusters[charFrom] == glyphStart)
1634                     charFrom++;
1635             if (charFrom < ilen) {
1636                 glyphStart = logClusters[charFrom];
1637                 int charEnd = from + len - 1 - pos;
1638                 if (charEnd >= ilen)
1639                     charEnd = ilen-1;
1640                 int glyphEnd = logClusters[charEnd];
1641                 while (charEnd < ilen && logClusters[charEnd] == glyphEnd)
1642                     charEnd++;
1643                 glyphEnd = (charEnd == ilen) ? si->num_glyphs : logClusters[charEnd];
1644
1645 //                 qDebug("char: start=%d end=%d / glyph: start = %d, end = %d", charFrom, charEnd, glyphStart, glyphEnd);
1646                 for (int i = glyphStart; i < glyphEnd; i++)
1647                     w += glyphs.advances_x[i] * !glyphs.attributes[i].dontPrint;
1648             }
1649         }
1650     }
1651 //     qDebug("   --> w= %d ", w);
1652     return w;
1653 }
1654
1655 glyph_metrics_t QTextEngine::boundingBox(int from,  int len) const
1656 {
1657     itemize();
1658
1659     glyph_metrics_t gm;
1660
1661     for (int i = 0; i < layoutData->items.size(); i++) {
1662         const QScriptItem *si = layoutData->items.constData() + i;
1663
1664         int pos = si->position;
1665         int ilen = length(i);
1666         if (pos > from + len)
1667             break;
1668         if (pos + ilen > from) {
1669             if (!si->num_glyphs)
1670                 shape(i);
1671
1672             if (si->analysis.flags == QScriptAnalysis::Object) {
1673                 gm.width += si->width;
1674                 continue;
1675             } else if (si->analysis.flags == QScriptAnalysis::Tab) {
1676                 gm.width += calculateTabWidth(i, gm.width);
1677                 continue;
1678             }
1679
1680             unsigned short *logClusters = this->logClusters(si);
1681             QGlyphLayout glyphs = shapedGlyphs(si);
1682
1683             // do the simple thing for now and give the first glyph in a cluster the full width, all other ones 0.
1684             int charFrom = from - pos;
1685             if (charFrom < 0)
1686                 charFrom = 0;
1687             int glyphStart = logClusters[charFrom];
1688             if (charFrom > 0 && logClusters[charFrom-1] == glyphStart)
1689                 while (charFrom < ilen && logClusters[charFrom] == glyphStart)
1690                     charFrom++;
1691             if (charFrom < ilen) {
1692                 QFontEngine *fe = fontEngine(*si);
1693                 glyphStart = logClusters[charFrom];
1694                 int charEnd = from + len - 1 - pos;
1695                 if (charEnd >= ilen)
1696                     charEnd = ilen-1;
1697                 int glyphEnd = logClusters[charEnd];
1698                 while (charEnd < ilen && logClusters[charEnd] == glyphEnd)
1699                     charEnd++;
1700                 glyphEnd = (charEnd == ilen) ? si->num_glyphs : logClusters[charEnd];
1701                 if (glyphStart <= glyphEnd ) {
1702                     glyph_metrics_t m = fe->boundingBox(glyphs.mid(glyphStart, glyphEnd - glyphStart));
1703                     gm.x = qMin(gm.x, m.x + gm.xoff);
1704                     gm.y = qMin(gm.y, m.y + gm.yoff);
1705                     gm.width = qMax(gm.width, m.width+gm.xoff);
1706                     gm.height = qMax(gm.height, m.height+gm.yoff);
1707                     gm.xoff += m.xoff;
1708                     gm.yoff += m.yoff;
1709                 }
1710             }
1711         }
1712     }
1713     return gm;
1714 }
1715
1716 glyph_metrics_t QTextEngine::tightBoundingBox(int from,  int len) const
1717 {
1718     itemize();
1719
1720     glyph_metrics_t gm;
1721
1722     for (int i = 0; i < layoutData->items.size(); i++) {
1723         const QScriptItem *si = layoutData->items.constData() + i;
1724         int pos = si->position;
1725         int ilen = length(i);
1726         if (pos > from + len)
1727             break;
1728         if (pos + len > from) {
1729             if (!si->num_glyphs)
1730                 shape(i);
1731             unsigned short *logClusters = this->logClusters(si);
1732             QGlyphLayout glyphs = shapedGlyphs(si);
1733
1734             // do the simple thing for now and give the first glyph in a cluster the full width, all other ones 0.
1735             int charFrom = from - pos;
1736             if (charFrom < 0)
1737                 charFrom = 0;
1738             int glyphStart = logClusters[charFrom];
1739             if (charFrom > 0 && logClusters[charFrom-1] == glyphStart)
1740                 while (charFrom < ilen && logClusters[charFrom] == glyphStart)
1741                     charFrom++;
1742             if (charFrom < ilen) {
1743                 glyphStart = logClusters[charFrom];
1744                 int charEnd = from + len - 1 - pos;
1745                 if (charEnd >= ilen)
1746                     charEnd = ilen-1;
1747                 int glyphEnd = logClusters[charEnd];
1748                 while (charEnd < ilen && logClusters[charEnd] == glyphEnd)
1749                     charEnd++;
1750                 glyphEnd = (charEnd == ilen) ? si->num_glyphs : logClusters[charEnd];
1751                 if (glyphStart <= glyphEnd ) {
1752                     QFontEngine *fe = fontEngine(*si);
1753                     glyph_metrics_t m = fe->tightBoundingBox(glyphs.mid(glyphStart, glyphEnd - glyphStart));
1754                     gm.x = qMin(gm.x, m.x + gm.xoff);
1755                     gm.y = qMin(gm.y, m.y + gm.yoff);
1756                     gm.width = qMax(gm.width, m.width+gm.xoff);
1757                     gm.height = qMax(gm.height, m.height+gm.yoff);
1758                     gm.xoff += m.xoff;
1759                     gm.yoff += m.yoff;
1760                 }
1761             }
1762         }
1763     }
1764     return gm;
1765 }
1766
1767 QFont QTextEngine::font(const QScriptItem &si) const
1768 {
1769     QFont font = fnt;
1770     if (hasFormats()) {
1771         QTextCharFormat f = format(&si);
1772         font = f.font();
1773
1774         if (block.docHandle() && block.docHandle()->layout()) {
1775             // Make sure we get the right dpi on printers
1776             QPaintDevice *pdev = block.docHandle()->layout()->paintDevice();
1777             if (pdev)
1778                 font = QFont(font, pdev);
1779         } else {
1780             font = font.resolve(fnt);
1781         }
1782         QTextCharFormat::VerticalAlignment valign = f.verticalAlignment();
1783         if (valign == QTextCharFormat::AlignSuperScript || valign == QTextCharFormat::AlignSubScript) {
1784             if (font.pointSize() != -1)
1785                 font.setPointSize((font.pointSize() * 2) / 3);
1786             else
1787                 font.setPixelSize((font.pixelSize() * 2) / 3);
1788         }
1789     }
1790
1791     if (si.analysis.flags == QScriptAnalysis::SmallCaps)
1792         font = font.d->smallCapsFont();
1793
1794     return font;
1795 }
1796
1797 QTextEngine::FontEngineCache::FontEngineCache()
1798 {
1799     reset();
1800 }
1801
1802 //we cache the previous results of this function, as calling it numerous times with the same effective
1803 //input is common (and hard to cache at a higher level)
1804 QFontEngine *QTextEngine::fontEngine(const QScriptItem &si, QFixed *ascent, QFixed *descent, QFixed *leading) const
1805 {
1806     QFontEngine *engine = 0;
1807     QFontEngine *scaledEngine = 0;
1808     int script = si.analysis.script;
1809
1810     QFont font = fnt;
1811     if (hasFormats()) {
1812         if (feCache.prevFontEngine && feCache.prevPosition == si.position && feCache.prevLength == length(&si) && feCache.prevScript == script) {
1813             engine = feCache.prevFontEngine;
1814             scaledEngine = feCache.prevScaledFontEngine;
1815         } else {
1816             QTextCharFormat f = format(&si);
1817             font = f.font();
1818
1819             if (block.docHandle() && block.docHandle()->layout()) {
1820                 // Make sure we get the right dpi on printers
1821                 QPaintDevice *pdev = block.docHandle()->layout()->paintDevice();
1822                 if (pdev)
1823                     font = QFont(font, pdev);
1824             } else {
1825                 font = font.resolve(fnt);
1826             }
1827             engine = font.d->engineForScript(script);
1828             QTextCharFormat::VerticalAlignment valign = f.verticalAlignment();
1829             if (valign == QTextCharFormat::AlignSuperScript || valign == QTextCharFormat::AlignSubScript) {
1830                 if (font.pointSize() != -1)
1831                     font.setPointSize((font.pointSize() * 2) / 3);
1832                 else
1833                     font.setPixelSize((font.pixelSize() * 2) / 3);
1834                 scaledEngine = font.d->engineForScript(script);
1835             }
1836             feCache.prevFontEngine = engine;
1837             if (engine)
1838                 engine->ref.ref();
1839             feCache.prevScaledFontEngine = scaledEngine;
1840             if (scaledEngine)
1841                 scaledEngine->ref.ref();
1842             feCache.prevScript = script;
1843             feCache.prevPosition = si.position;
1844             feCache.prevLength = length(&si);
1845         }
1846     } else {
1847         if (feCache.prevFontEngine && feCache.prevScript == script && feCache.prevPosition == -1)
1848             engine = feCache.prevFontEngine;
1849         else {
1850             engine = font.d->engineForScript(script);
1851             feCache.prevFontEngine = engine;
1852             if (engine)
1853                 engine->ref.ref();
1854             feCache.prevScript = script;
1855             feCache.prevPosition = -1;
1856             feCache.prevLength = -1;
1857             feCache.prevScaledFontEngine = 0;
1858         }
1859     }
1860
1861     if (si.analysis.flags == QScriptAnalysis::SmallCaps) {
1862         QFontPrivate *p = font.d->smallCapsFontPrivate();
1863         scaledEngine = p->engineForScript(script);
1864     }
1865
1866     if (ascent) {
1867         *ascent = engine->ascent();
1868         *descent = engine->descent();
1869         *leading = engine->leading();
1870     }
1871
1872     if (scaledEngine)
1873         return scaledEngine;
1874     return engine;
1875 }
1876
1877 struct QJustificationPoint {
1878     int type;
1879     QFixed kashidaWidth;
1880     QGlyphLayout glyph;
1881     QFontEngine *fontEngine;
1882 };
1883
1884 Q_DECLARE_TYPEINFO(QJustificationPoint, Q_PRIMITIVE_TYPE);
1885
1886 static void set(QJustificationPoint *point, int type, const QGlyphLayout &glyph, QFontEngine *fe)
1887 {
1888     point->type = type;
1889     point->glyph = glyph;
1890     point->fontEngine = fe;
1891
1892     if (type >= HB_Arabic_Normal) {
1893         QChar ch(0x640); // Kashida character
1894         QGlyphLayoutArray<8> glyphs;
1895         int nglyphs = 7;
1896         fe->stringToCMap(&ch, 1, &glyphs, &nglyphs, 0);
1897         if (glyphs.glyphs[0] && glyphs.advances_x[0] != 0) {
1898             point->kashidaWidth = glyphs.advances_x[0];
1899         } else {
1900             point->type = HB_NoJustification;
1901             point->kashidaWidth = 0;
1902         }
1903     }
1904 }
1905
1906
1907 void QTextEngine::justify(const QScriptLine &line)
1908 {
1909 //     qDebug("justify: line.gridfitted = %d, line.justified=%d", line.gridfitted, line.justified);
1910     if (line.gridfitted && line.justified)
1911         return;
1912
1913     if (!line.gridfitted) {
1914         // redo layout in device metrics, then adjust
1915         const_cast<QScriptLine &>(line).gridfitted = true;
1916     }
1917
1918     if ((option.alignment() & Qt::AlignHorizontal_Mask) != Qt::AlignJustify)
1919         return;
1920
1921     itemize();
1922
1923     if (!forceJustification) {
1924         int end = line.from + (int)line.length;
1925         if (end == layoutData->string.length())
1926             return; // no justification at end of paragraph
1927         if (end && layoutData->items[findItem(end-1)].analysis.flags == QScriptAnalysis::LineOrParagraphSeparator)
1928             return; // no justification at the end of an explicitly separated line
1929     }
1930
1931     // justify line
1932     int maxJustify = 0;
1933
1934     // don't include trailing white spaces when doing justification
1935     int line_length = line.length;
1936     const HB_CharAttributes *a = attributes();
1937     if (! a)
1938         return;
1939     a += line.from;
1940     while (line_length && a[line_length-1].whiteSpace)
1941         --line_length;
1942     // subtract one char more, as we can't justfy after the last character
1943     --line_length;
1944
1945     if (!line_length)
1946         return;
1947
1948     int firstItem = findItem(line.from);
1949     int nItems = findItem(line.from + line_length - 1) - firstItem + 1;
1950
1951     QVarLengthArray<QJustificationPoint> justificationPoints;
1952     int nPoints = 0;
1953 //     qDebug("justifying from %d len %d, firstItem=%d, nItems=%d (%s)", line.from, line_length, firstItem, nItems, layoutData->string.mid(line.from, line_length).toUtf8().constData());
1954     QFixed minKashida = 0x100000;
1955
1956     // we need to do all shaping before we go into the next loop, as we there
1957     // store pointers to the glyph data that could get reallocated by the shaping
1958     // process.
1959     for (int i = 0; i < nItems; ++i) {
1960         QScriptItem &si = layoutData->items[firstItem + i];
1961         if (!si.num_glyphs)
1962             shape(firstItem + i);
1963     }
1964
1965     for (int i = 0; i < nItems; ++i) {
1966         QScriptItem &si = layoutData->items[firstItem + i];
1967
1968         int kashida_type = HB_Arabic_Normal;
1969         int kashida_pos = -1;
1970
1971         int start = qMax(line.from - si.position, 0);
1972         int end = qMin(line.from + line_length - (int)si.position, length(firstItem+i));
1973
1974         unsigned short *log_clusters = logClusters(&si);
1975
1976         int gs = log_clusters[start];
1977         int ge = (end == length(firstItem+i) ? si.num_glyphs : log_clusters[end]);
1978
1979         const QGlyphLayout g = shapedGlyphs(&si);
1980
1981         for (int i = gs; i < ge; ++i) {
1982             g.justifications[i].type = QGlyphJustification::JustifyNone;
1983             g.justifications[i].nKashidas = 0;
1984             g.justifications[i].space_18d6 = 0;
1985
1986             justificationPoints.resize(nPoints+3);
1987             int justification = g.attributes[i].justification;
1988
1989             switch(justification) {
1990             case HB_NoJustification:
1991                 break;
1992             case HB_Space          :
1993                 // fall through
1994             case HB_Arabic_Space   :
1995                 if (kashida_pos >= 0) {
1996 //                     qDebug("kashida position at %d in word", kashida_pos);
1997                     set(&justificationPoints[nPoints], kashida_type, g.mid(kashida_pos), fontEngine(si));
1998                     if (justificationPoints[nPoints].kashidaWidth > 0) {
1999                         minKashida = qMin(minKashida, justificationPoints[nPoints].kashidaWidth);
2000                         maxJustify = qMax(maxJustify, justificationPoints[nPoints].type);
2001                         ++nPoints;
2002                     }
2003                 }
2004                 kashida_pos = -1;
2005                 kashida_type = HB_Arabic_Normal;
2006                 // fall through
2007             case HB_Character      :
2008                 set(&justificationPoints[nPoints++], justification, g.mid(i), fontEngine(si));
2009                 maxJustify = qMax(maxJustify, justification);
2010                 break;
2011             case HB_Arabic_Normal  :
2012             case HB_Arabic_Waw     :
2013             case HB_Arabic_BaRa    :
2014             case HB_Arabic_Alef    :
2015             case HB_Arabic_HaaDal  :
2016             case HB_Arabic_Seen    :
2017             case HB_Arabic_Kashida :
2018                 if (justification >= kashida_type) {
2019                     kashida_pos = i;
2020                     kashida_type = justification;
2021                 }
2022             }
2023         }
2024         if (kashida_pos >= 0) {
2025             set(&justificationPoints[nPoints], kashida_type, g.mid(kashida_pos), fontEngine(si));
2026             if (justificationPoints[nPoints].kashidaWidth > 0) {
2027                 minKashida = qMin(minKashida, justificationPoints[nPoints].kashidaWidth);
2028                 maxJustify = qMax(maxJustify, justificationPoints[nPoints].type);
2029                 ++nPoints;
2030             }
2031         }
2032     }
2033
2034     QFixed need = line.width - line.textWidth;
2035     if (need < 0) {
2036         // line overflows already!
2037         const_cast<QScriptLine &>(line).justified = true;
2038         return;
2039     }
2040
2041 //     qDebug("doing justification: textWidth=%x, requested=%x, maxJustify=%d", line.textWidth.value(), line.width.value(), maxJustify);
2042 //     qDebug("     minKashida=%f, need=%f", minKashida.toReal(), need.toReal());
2043
2044     // distribute in priority order
2045     if (maxJustify >= HB_Arabic_Normal) {
2046         while (need >= minKashida) {
2047             for (int type = maxJustify; need >= minKashida && type >= HB_Arabic_Normal; --type) {
2048                 for (int i = 0; need >= minKashida && i < nPoints; ++i) {
2049                     if (justificationPoints[i].type == type && justificationPoints[i].kashidaWidth <= need) {
2050                         justificationPoints[i].glyph.justifications->nKashidas++;
2051                         // ############
2052                         justificationPoints[i].glyph.justifications->space_18d6 += justificationPoints[i].kashidaWidth.value();
2053                         need -= justificationPoints[i].kashidaWidth;
2054 //                         qDebug("adding kashida type %d with width %x, neednow %x", type, justificationPoints[i].kashidaWidth, need.value());
2055                     }
2056                 }
2057             }
2058         }
2059     }
2060     Q_ASSERT(need >= 0);
2061     if (!need)
2062         goto end;
2063
2064     maxJustify = qMin(maxJustify, (int)HB_Space);
2065     for (int type = maxJustify; need != 0 && type > 0; --type) {
2066         int n = 0;
2067         for (int i = 0; i < nPoints; ++i) {
2068             if (justificationPoints[i].type == type)
2069                 ++n;
2070         }
2071 //          qDebug("number of points for justification type %d: %d", type, n);
2072
2073
2074         if (!n)
2075             continue;
2076
2077         for (int i = 0; i < nPoints; ++i) {
2078             if (justificationPoints[i].type == type) {
2079                 QFixed add = need/n;
2080 //                  qDebug("adding %x to glyph %x", add.value(), justificationPoints[i].glyph->glyph);
2081                 justificationPoints[i].glyph.justifications[0].space_18d6 = add.value();
2082                 need -= add;
2083                 --n;
2084             }
2085         }
2086
2087         Q_ASSERT(!need);
2088     }
2089  end:
2090     const_cast<QScriptLine &>(line).justified = true;
2091 }
2092
2093 void QScriptLine::setDefaultHeight(QTextEngine *eng)
2094 {
2095     QFont f;
2096     QFontEngine *e;
2097
2098     if (eng->block.docHandle() && eng->block.docHandle()->layout()) {
2099         f = eng->block.charFormat().font();
2100         // Make sure we get the right dpi on printers
2101         QPaintDevice *pdev = eng->block.docHandle()->layout()->paintDevice();
2102         if (pdev)
2103             f = QFont(f, pdev);
2104         e = f.d->engineForScript(QUnicodeTables::Common);
2105     } else {
2106         e = eng->fnt.d->engineForScript(QUnicodeTables::Common);
2107     }
2108
2109     QFixed other_ascent = e->ascent();
2110     QFixed other_descent = e->descent();
2111     QFixed other_leading = e->leading();
2112     leading = qMax(leading + ascent, other_leading + other_ascent) - qMax(ascent, other_ascent);
2113     ascent = qMax(ascent, other_ascent);
2114     descent = qMax(descent, other_descent);
2115 }
2116
2117 QTextEngine::LayoutData::LayoutData()
2118 {
2119     memory = 0;
2120     allocated = 0;
2121     memory_on_stack = false;
2122     used = 0;
2123     hasBidi = false;
2124     layoutState = LayoutEmpty;
2125     haveCharAttributes = false;
2126     logClustersPtr = 0;
2127     available_glyphs = 0;
2128 }
2129
2130 QTextEngine::LayoutData::LayoutData(const QString &str, void **stack_memory, int _allocated)
2131     : string(str)
2132 {
2133     allocated = _allocated;
2134
2135     int space_charAttributes = sizeof(HB_CharAttributes)*string.length()/sizeof(void*) + 1;
2136     int space_logClusters = sizeof(unsigned short)*string.length()/sizeof(void*) + 1;
2137     available_glyphs = ((int)allocated - space_charAttributes - space_logClusters)*(int)sizeof(void*)/(int)QGlyphLayout::spaceNeededForGlyphLayout(1);
2138
2139     if (available_glyphs < str.length()) {
2140         // need to allocate on the heap
2141         allocated = 0;
2142
2143         memory_on_stack = false;
2144         memory = 0;
2145         logClustersPtr = 0;
2146     } else {
2147         memory_on_stack = true;
2148         memory = stack_memory;
2149         logClustersPtr = (unsigned short *)(memory + space_charAttributes);
2150
2151         void *m = memory + space_charAttributes + space_logClusters;
2152         glyphLayout = QGlyphLayout(reinterpret_cast<char *>(m), str.length());
2153         glyphLayout.clear();
2154         memset(memory, 0, space_charAttributes*sizeof(void *));
2155     }
2156     used = 0;
2157     hasBidi = false;
2158     layoutState = LayoutEmpty;
2159     haveCharAttributes = false;
2160 }
2161
2162 QTextEngine::LayoutData::~LayoutData()
2163 {
2164     if (!memory_on_stack)
2165         free(memory);
2166     memory = 0;
2167 }
2168
2169 bool QTextEngine::LayoutData::reallocate(int totalGlyphs)
2170 {
2171     Q_ASSERT(totalGlyphs >= glyphLayout.numGlyphs);
2172     if (memory_on_stack && available_glyphs >= totalGlyphs) {
2173         glyphLayout.grow(glyphLayout.data(), totalGlyphs);
2174         return true;
2175     }
2176
2177     int space_charAttributes = sizeof(HB_CharAttributes)*string.length()/sizeof(void*) + 1;
2178     int space_logClusters = sizeof(unsigned short)*string.length()/sizeof(void*) + 1;
2179     int space_glyphs = QGlyphLayout::spaceNeededForGlyphLayout(totalGlyphs)/sizeof(void*) + 2;
2180
2181     int newAllocated = space_charAttributes + space_glyphs + space_logClusters;
2182     // These values can be negative if the length of string/glyphs causes overflow,
2183     // we can't layout such a long string all at once, so return false here to
2184     // indicate there is a failure
2185     if (space_charAttributes < 0 || space_logClusters < 0 || space_glyphs < 0 || newAllocated < allocated) {
2186         layoutState = LayoutFailed;
2187         return false;
2188     }
2189
2190     void **newMem = memory;
2191     newMem = (void **)::realloc(memory_on_stack ? 0 : memory, newAllocated*sizeof(void *));
2192     if (!newMem) {
2193         layoutState = LayoutFailed;
2194         return false;
2195     }
2196     if (memory_on_stack)
2197         memcpy(newMem, memory, allocated*sizeof(void *));
2198     memory = newMem;
2199     memory_on_stack = false;
2200
2201     void **m = memory;
2202     m += space_charAttributes;
2203     logClustersPtr = (unsigned short *) m;
2204     m += space_logClusters;
2205
2206     const int space_preGlyphLayout = space_charAttributes + space_logClusters;
2207     if (allocated < space_preGlyphLayout)
2208         memset(memory + allocated, 0, (space_preGlyphLayout - allocated)*sizeof(void *));
2209
2210     glyphLayout.grow(reinterpret_cast<char *>(m), totalGlyphs);
2211
2212     allocated = newAllocated;
2213     return true;
2214 }
2215
2216 // grow to the new size, copying the existing data to the new layout
2217 void QGlyphLayout::grow(char *address, int totalGlyphs)
2218 {
2219     QGlyphLayout oldLayout(address, numGlyphs);
2220     QGlyphLayout newLayout(address, totalGlyphs);
2221
2222     if (numGlyphs) {
2223         // move the existing data
2224         memmove(newLayout.attributes, oldLayout.attributes, numGlyphs * sizeof(HB_GlyphAttributes));
2225         memmove(newLayout.justifications, oldLayout.justifications, numGlyphs * sizeof(QGlyphJustification));
2226         memmove(newLayout.advances_y, oldLayout.advances_y, numGlyphs * sizeof(QFixed));
2227         memmove(newLayout.advances_x, oldLayout.advances_x, numGlyphs * sizeof(QFixed));
2228         memmove(newLayout.glyphs, oldLayout.glyphs, numGlyphs * sizeof(HB_Glyph));
2229     }
2230
2231     // clear the new data
2232     newLayout.clear(numGlyphs);
2233
2234     *this = newLayout;
2235 }
2236
2237 void QTextEngine::freeMemory()
2238 {
2239     if (!stackEngine) {
2240         delete layoutData;
2241         layoutData = 0;
2242     } else {
2243         layoutData->used = 0;
2244         layoutData->hasBidi = false;
2245         layoutData->layoutState = LayoutEmpty;
2246         layoutData->haveCharAttributes = false;
2247     }
2248     for (int i = 0; i < lines.size(); ++i) {
2249         lines[i].justified = 0;
2250         lines[i].gridfitted = 0;
2251     }
2252 }
2253
2254 int QTextEngine::formatIndex(const QScriptItem *si) const
2255 {
2256     if (specialData && !specialData->resolvedFormatIndices.isEmpty())
2257         return specialData->resolvedFormatIndices.at(si - &layoutData->items[0]);
2258     QTextDocumentPrivate *p = block.docHandle();
2259     if (!p)
2260         return -1;
2261     int pos = si->position;
2262     if (specialData && si->position >= specialData->preeditPosition) {
2263         if (si->position < specialData->preeditPosition + specialData->preeditText.length())
2264             pos = qMax(specialData->preeditPosition - 1, 0);
2265         else
2266             pos -= specialData->preeditText.length();
2267     }
2268     QTextDocumentPrivate::FragmentIterator it = p->find(block.position() + pos);
2269     return it.value()->format;
2270 }
2271
2272
2273 QTextCharFormat QTextEngine::format(const QScriptItem *si) const
2274 {
2275     QTextCharFormat format;
2276     const QTextFormatCollection *formats = 0;
2277     if (block.docHandle()) {
2278         formats = this->formats();
2279         format = formats->charFormat(formatIndex(si));
2280     }
2281     if (specialData && specialData->resolvedFormatIndices.isEmpty()) {
2282         int end = si->position + length(si);
2283         for (int i = 0; i < specialData->addFormats.size(); ++i) {
2284             const QTextLayout::FormatRange &r = specialData->addFormats.at(i);
2285             if (r.start <= si->position && r.start + r.length >= end) {
2286                 if (!specialData->addFormatIndices.isEmpty())
2287                     format.merge(formats->format(specialData->addFormatIndices.at(i)));
2288                 else
2289                     format.merge(r.format);
2290             }
2291         }
2292     }
2293     return format;
2294 }
2295
2296 void QTextEngine::addRequiredBoundaries() const
2297 {
2298     if (specialData) {
2299         for (int i = 0; i < specialData->addFormats.size(); ++i) {
2300             const QTextLayout::FormatRange &r = specialData->addFormats.at(i);
2301             setBoundary(r.start);
2302             setBoundary(r.start + r.length);
2303             //qDebug("adding boundaries %d %d", r.start, r.start+r.length);
2304         }
2305     }
2306 }
2307
2308 bool QTextEngine::atWordSeparator(int position) const
2309 {
2310     const QChar c = layoutData->string.at(position);
2311     switch (c.toLatin1()) {
2312     case '.':
2313     case ',':
2314     case '?':
2315     case '!':
2316     case '@':
2317     case '#':
2318     case '$':
2319     case ':':
2320     case ';':
2321     case '-':
2322     case '<':
2323     case '>':
2324     case '[':
2325     case ']':
2326     case '(':
2327     case ')':
2328     case '{':
2329     case '}':
2330     case '=':
2331     case '/':
2332     case '+':
2333     case '%':
2334     case '&':
2335     case '^':
2336     case '*':
2337     case '\'':
2338     case '"':
2339     case '`':
2340     case '~':
2341     case '|':
2342         return true;
2343     default:
2344         return false;
2345     }
2346 }
2347
2348 bool QTextEngine::atSpace(int position) const
2349 {
2350     const QChar c = layoutData->string.at(position);
2351
2352     return c == QLatin1Char(' ')
2353         || c == QChar::Nbsp
2354         || c == QChar::LineSeparator
2355         || c == QLatin1Char('\t')
2356         ;
2357 }
2358
2359
2360 void QTextEngine::indexAdditionalFormats()
2361 {
2362     if (!block.docHandle())
2363         return;
2364
2365     specialData->addFormatIndices.resize(specialData->addFormats.count());
2366     QTextFormatCollection * const formats = this->formats();
2367
2368     for (int i = 0; i < specialData->addFormats.count(); ++i) {
2369         specialData->addFormatIndices[i] = formats->indexForFormat(specialData->addFormats.at(i).format);
2370         specialData->addFormats[i].format = QTextCharFormat();
2371     }
2372 }
2373
2374 /* These two helper functions are used to determine whether we need to insert a ZWJ character
2375    between the text that gets truncated and the ellipsis. This is important to get
2376    correctly shaped results for arabic text.
2377 */
2378 static bool nextCharJoins(const QString &string, int pos)
2379 {
2380     while (pos < string.length() && string.at(pos).category() == QChar::Mark_NonSpacing)
2381         ++pos;
2382     if (pos == string.length())
2383         return false;
2384     return string.at(pos).joining() != QChar::OtherJoining;
2385 }
2386
2387 static bool prevCharJoins(const QString &string, int pos)
2388 {
2389     while (pos > 0 && string.at(pos - 1).category() == QChar::Mark_NonSpacing)
2390         --pos;
2391     if (pos == 0)
2392         return false;
2393     return (string.at(pos - 1).joining() == QChar::Dual || string.at(pos - 1).joining() == QChar::Center);
2394 }
2395
2396 QString QTextEngine::elidedText(Qt::TextElideMode mode, const QFixed &width, int flags) const
2397 {
2398 //    qDebug() << "elidedText; available width" << width.toReal() << "text width:" << this->width(0, layoutData->string.length()).toReal();
2399
2400     if (flags & Qt::TextShowMnemonic) {
2401         itemize();
2402         HB_CharAttributes *attributes = const_cast<HB_CharAttributes *>(this->attributes());
2403         if (!attributes)
2404             return QString();
2405         for (int i = 0; i < layoutData->items.size(); ++i) {
2406             QScriptItem &si = layoutData->items[i];
2407             if (!si.num_glyphs)
2408                 shape(i);
2409
2410             unsigned short *logClusters = this->logClusters(&si);
2411             QGlyphLayout glyphs = shapedGlyphs(&si);
2412
2413             const int end = si.position + length(&si);
2414             for (int i = si.position; i < end - 1; ++i) {
2415                 if (layoutData->string.at(i) == QLatin1Char('&')) {
2416                     const int gp = logClusters[i - si.position];
2417                     glyphs.attributes[gp].dontPrint = true;
2418                     attributes[i + 1].charStop = false;
2419                     attributes[i + 1].whiteSpace = false;
2420                     attributes[i + 1].lineBreakType = HB_NoBreak;
2421                     if (layoutData->string.at(i + 1) == QLatin1Char('&'))
2422                         ++i;
2423                 }
2424             }
2425         }
2426     }
2427
2428     validate();
2429
2430     if (mode == Qt::ElideNone
2431         || this->width(0, layoutData->string.length()) <= width
2432         || layoutData->string.length() <= 1)
2433         return layoutData->string;
2434
2435     QFixed ellipsisWidth;
2436     QString ellipsisText;
2437     {
2438         QChar ellipsisChar(0x2026);
2439
2440         QFontEngine *fe = fnt.d->engineForScript(QUnicodeTables::Common);
2441
2442         QGlyphLayoutArray<1> ellipsisGlyph;
2443         {
2444             QFontEngine *feForEllipsis = (fe->type() == QFontEngine::Multi)
2445                 ? static_cast<QFontEngineMulti *>(fe)->engine(0)
2446                 : fe;
2447
2448             if (feForEllipsis->type() == QFontEngine::Mac)
2449                 feForEllipsis = fe;
2450
2451             // the lookup can be really slow when we use XLFD fonts
2452             if (feForEllipsis->type() != QFontEngine::XLFD
2453                 && feForEllipsis->canRender(&ellipsisChar, 1)) {
2454                     int nGlyphs = 1;
2455                     feForEllipsis->stringToCMap(&ellipsisChar, 1, &ellipsisGlyph, &nGlyphs, 0);
2456                 }
2457         }
2458
2459         if (ellipsisGlyph.glyphs[0]) {
2460             ellipsisWidth = ellipsisGlyph.advances_x[0];
2461             ellipsisText = ellipsisChar;
2462         } else {
2463             QString dotDotDot(QLatin1String("..."));
2464
2465             QGlyphLayoutArray<3> glyphs;
2466             int nGlyphs = 3;
2467             if (!fe->stringToCMap(dotDotDot.constData(), 3, &glyphs, &nGlyphs, 0))
2468                 // should never happen...
2469                 return layoutData->string;
2470             for (int i = 0; i < nGlyphs; ++i)
2471                 ellipsisWidth += glyphs.advances_x[i];
2472             ellipsisText = dotDotDot;
2473         }
2474     }
2475
2476     const QFixed availableWidth = width - ellipsisWidth;
2477     if (availableWidth < 0)
2478         return QString();
2479
2480     const HB_CharAttributes *attributes = this->attributes();
2481     if (!attributes)
2482         return QString();
2483
2484     if (mode == Qt::ElideRight) {
2485         QFixed currentWidth;
2486         int pos;
2487         int nextBreak = 0;
2488
2489         do {
2490             pos = nextBreak;
2491
2492             ++nextBreak;
2493             while (nextBreak < layoutData->string.length() && !attributes[nextBreak].charStop)
2494                 ++nextBreak;
2495
2496             currentWidth += this->width(pos, nextBreak - pos);
2497         } while (nextBreak < layoutData->string.length()
2498                  && currentWidth < availableWidth);
2499
2500         if (nextCharJoins(layoutData->string, pos))
2501             ellipsisText.prepend(QChar(0x200d) /* ZWJ */);
2502
2503         return layoutData->string.left(pos) + ellipsisText;
2504     } else if (mode == Qt::ElideLeft) {
2505         QFixed currentWidth;
2506         int pos;
2507         int nextBreak = layoutData->string.length();
2508
2509         do {
2510             pos = nextBreak;
2511
2512             --nextBreak;
2513             while (nextBreak > 0 && !attributes[nextBreak].charStop)
2514                 --nextBreak;
2515
2516             currentWidth += this->width(nextBreak, pos - nextBreak);
2517         } while (nextBreak > 0
2518                  && currentWidth < availableWidth);
2519
2520         if (prevCharJoins(layoutData->string, pos))
2521             ellipsisText.append(QChar(0x200d) /* ZWJ */);
2522
2523         return ellipsisText + layoutData->string.mid(pos);
2524     } else if (mode == Qt::ElideMiddle) {
2525         QFixed leftWidth;
2526         QFixed rightWidth;
2527
2528         int leftPos = 0;
2529         int nextLeftBreak = 0;
2530
2531         int rightPos = layoutData->string.length();
2532         int nextRightBreak = layoutData->string.length();
2533
2534         do {
2535             leftPos = nextLeftBreak;
2536             rightPos = nextRightBreak;
2537
2538             ++nextLeftBreak;
2539             while (nextLeftBreak < layoutData->string.length() && !attributes[nextLeftBreak].charStop)
2540                 ++nextLeftBreak;
2541
2542             --nextRightBreak;
2543             while (nextRightBreak > 0 && !attributes[nextRightBreak].charStop)
2544                 --nextRightBreak;
2545
2546             leftWidth += this->width(leftPos, nextLeftBreak - leftPos);
2547             rightWidth += this->width(nextRightBreak, rightPos - nextRightBreak);
2548         } while (nextLeftBreak < layoutData->string.length()
2549                  && nextRightBreak > 0
2550                  && leftWidth + rightWidth < availableWidth);
2551
2552         if (nextCharJoins(layoutData->string, leftPos))
2553             ellipsisText.prepend(QChar(0x200d) /* ZWJ */);
2554         if (prevCharJoins(layoutData->string, rightPos))
2555             ellipsisText.append(QChar(0x200d) /* ZWJ */);
2556
2557         return layoutData->string.left(leftPos) + ellipsisText + layoutData->string.mid(rightPos);
2558     }
2559
2560     return layoutData->string;
2561 }
2562
2563 void QTextEngine::setBoundary(int strPos) const
2564 {
2565     if (strPos <= 0 || strPos >= layoutData->string.length())
2566         return;
2567
2568     int itemToSplit = 0;
2569     while (itemToSplit < layoutData->items.size() && layoutData->items.at(itemToSplit).position <= strPos)
2570         itemToSplit++;
2571     itemToSplit--;
2572     if (layoutData->items.at(itemToSplit).position == strPos) {
2573         // already a split at the requested position
2574         return;
2575     }
2576     splitItem(itemToSplit, strPos - layoutData->items.at(itemToSplit).position);
2577 }
2578
2579 void QTextEngine::splitItem(int item, int pos) const
2580 {
2581     if (pos <= 0)
2582         return;
2583
2584     layoutData->items.insert(item + 1, layoutData->items[item]);
2585     QScriptItem &oldItem = layoutData->items[item];
2586     QScriptItem &newItem = layoutData->items[item+1];
2587     newItem.position += pos;
2588
2589     if (oldItem.num_glyphs) {
2590         // already shaped, break glyphs aswell
2591         int breakGlyph = logClusters(&oldItem)[pos];
2592
2593         newItem.num_glyphs = oldItem.num_glyphs - breakGlyph;
2594         oldItem.num_glyphs = breakGlyph;
2595         newItem.glyph_data_offset = oldItem.glyph_data_offset + breakGlyph;
2596
2597         for (int i = 0; i < newItem.num_glyphs; i++)
2598             logClusters(&newItem)[i] -= breakGlyph;
2599
2600         QFixed w = 0;
2601         const QGlyphLayout g = shapedGlyphs(&oldItem);
2602         for(int j = 0; j < breakGlyph; ++j)
2603             w += g.advances_x[j];
2604
2605         newItem.width = oldItem.width - w;
2606         oldItem.width = w;
2607     }
2608
2609 //     qDebug("split at position %d itempos=%d", pos, item);
2610 }
2611
2612 QFixed QTextEngine::calculateTabWidth(int item, QFixed x) const
2613 {
2614     const QScriptItem &si = layoutData->items[item];
2615
2616     QFixed dpiScale = 1;
2617     if (block.docHandle() && block.docHandle()->layout()) {
2618         QPaintDevice *pdev = block.docHandle()->layout()->paintDevice();
2619         if (pdev)
2620             dpiScale = QFixed::fromReal(pdev->logicalDpiY() / qreal(qt_defaultDpiY()));
2621     } else {
2622         dpiScale = QFixed::fromReal(fnt.d->dpi / qreal(qt_defaultDpiY()));
2623     }
2624
2625     QList<QTextOption::Tab> tabArray = option.tabs();
2626     if (!tabArray.isEmpty()) {
2627         if (isRightToLeft()) { // rebase the tabArray positions.
2628             QList<QTextOption::Tab> newTabs;
2629             QList<QTextOption::Tab>::Iterator iter = tabArray.begin();
2630             while(iter != tabArray.end()) {
2631                 QTextOption::Tab tab = *iter;
2632                 if (tab.type == QTextOption::LeftTab)
2633                     tab.type = QTextOption::RightTab;
2634                 else if (tab.type == QTextOption::RightTab)
2635                     tab.type = QTextOption::LeftTab;
2636                 newTabs << tab;
2637                 ++iter;
2638             }
2639             tabArray = newTabs;
2640         }
2641         for (int i = 0; i < tabArray.size(); ++i) {
2642             QFixed tab = QFixed::fromReal(tabArray[i].position) * dpiScale;
2643             if (tab > x) {  // this is the tab we need.
2644                 QTextOption::Tab tabSpec = tabArray[i];
2645                 int tabSectionEnd = layoutData->string.count();
2646                 if (tabSpec.type == QTextOption::RightTab || tabSpec.type == QTextOption::CenterTab) {
2647                     // find next tab to calculate the width required.
2648                     tab = QFixed::fromReal(tabSpec.position);
2649                     for (int i=item + 1; i < layoutData->items.count(); i++) {
2650                         const QScriptItem &item = layoutData->items[i];
2651                         if (item.analysis.flags == QScriptAnalysis::TabOrObject) { // found it.
2652                             tabSectionEnd = item.position;
2653                             break;
2654                         }
2655                     }
2656                 }
2657                 else if (tabSpec.type == QTextOption::DelimiterTab)
2658                     // find delimitor character to calculate the width required
2659                     tabSectionEnd = qMax(si.position, layoutData->string.indexOf(tabSpec.delimiter, si.position) + 1);
2660
2661                 if (tabSectionEnd > si.position) {
2662                     QFixed length;
2663                     // Calculate the length of text between this tab and the tabSectionEnd
2664                     for (int i=item; i < layoutData->items.count(); i++) {
2665                         QScriptItem &item = layoutData->items[i];
2666                         if (item.position > tabSectionEnd || item.position <= si.position)
2667                             continue;
2668                         shape(i); // first, lets make sure relevant text is already shaped
2669                         QGlyphLayout glyphs = this->shapedGlyphs(&item);
2670                         const int end = qMin(item.position + item.num_glyphs, tabSectionEnd) - item.position;
2671                         for (int i=0; i < end; i++)
2672                             length += glyphs.advances_x[i] * !glyphs.attributes[i].dontPrint;
2673                         if (end + item.position == tabSectionEnd && tabSpec.type == QTextOption::DelimiterTab) // remove half of matching char
2674                             length -= glyphs.advances_x[end] / 2 * !glyphs.attributes[end].dontPrint;
2675                     }
2676
2677                     switch (tabSpec.type) {
2678                     case QTextOption::CenterTab:
2679                         length /= 2;
2680                         // fall through
2681                     case QTextOption::DelimiterTab:
2682                         // fall through
2683                     case QTextOption::RightTab:
2684                         tab = QFixed::fromReal(tabSpec.position) * dpiScale - length;
2685                         if (tab < 0) // default to tab taking no space
2686                             return QFixed();
2687                         break;
2688                     case QTextOption::LeftTab:
2689                         break;
2690                     }
2691                 }
2692                 return tab - x;
2693             }
2694         }
2695     }
2696     QFixed tab = QFixed::fromReal(option.tabStop());
2697     if (tab <= 0)
2698         tab = 80; // default
2699     tab *= dpiScale;
2700     QFixed nextTabPos = ((x / tab).truncate() + 1) * tab;
2701     QFixed tabWidth = nextTabPos - x;
2702
2703     return tabWidth;
2704 }
2705
2706 void QTextEngine::resolveAdditionalFormats() const
2707 {
2708     if (!specialData || specialData->addFormats.isEmpty()
2709         || !block.docHandle()
2710         || !specialData->resolvedFormatIndices.isEmpty())
2711         return;
2712
2713     QTextFormatCollection *collection = this->formats();
2714
2715     specialData->resolvedFormatIndices.clear();
2716     QVector<int> indices(layoutData->items.count());
2717     for (int i = 0; i < layoutData->items.count(); ++i) {
2718         QTextCharFormat f = format(&layoutData->items.at(i));
2719         indices[i] = collection->indexForFormat(f);
2720     }
2721     specialData->resolvedFormatIndices = indices;
2722 }
2723
2724 QFixed QTextEngine::leadingSpaceWidth(const QScriptLine &line)
2725 {
2726     if (!line.hasTrailingSpaces
2727         || (option.flags() & QTextOption::IncludeTrailingSpaces)
2728         || !isRightToLeft())
2729         return QFixed();
2730
2731     int pos = line.length;
2732     const HB_CharAttributes *attributes = this->attributes();
2733     if (!attributes)
2734         return QFixed();
2735     while (pos > 0 && attributes[line.from + pos - 1].whiteSpace)
2736         --pos;
2737     return width(line.from + pos, line.length - pos);
2738 }
2739
2740 QStackTextEngine::QStackTextEngine(const QString &string, const QFont &f)
2741     : QTextEngine(string, f),
2742       _layoutData(string, _memory, MemSize)
2743 {
2744     stackEngine = true;
2745     layoutData = &_layoutData;
2746 }
2747
2748 QTextItemInt::QTextItemInt(const QScriptItem &si, QFont *font, const QTextCharFormat &format)
2749     : justified(false), underlineStyle(QTextCharFormat::NoUnderline), charFormat(format),
2750       num_chars(0), chars(0), logClusters(0), f(0), fontEngine(0)
2751 {
2752     // explicitly initialize flags so that initFontAttributes can be called
2753     // multiple times on the same TextItem
2754     flags = 0;
2755     if (si.analysis.bidiLevel %2)
2756         flags |= QTextItem::RightToLeft;
2757     ascent = si.ascent;
2758     descent = si.descent;
2759     f = font;
2760     fontEngine = f->d->engineForScript(si.analysis.script);
2761     Q_ASSERT(fontEngine);
2762
2763     if (format.hasProperty(QTextFormat::TextUnderlineStyle)) {
2764         underlineStyle = format.underlineStyle();
2765     } else if (format.boolProperty(QTextFormat::FontUnderline)
2766                || f->d->underline) {
2767         underlineStyle = QTextCharFormat::SingleUnderline;
2768     }
2769
2770     // compat
2771     if (underlineStyle == QTextCharFormat::SingleUnderline)
2772         flags |= QTextItem::Underline;
2773
2774     if (f->d->overline || format.fontOverline())
2775         flags |= QTextItem::Overline;
2776     if (f->d->strikeOut || format.fontStrikeOut())
2777         flags |= QTextItem::StrikeOut;
2778 }
2779
2780 QTextItemInt::QTextItemInt(const QGlyphLayout &g, QFont *font, const QChar *chars_, int numChars, QFontEngine *fe)
2781     : flags(0), justified(false), underlineStyle(QTextCharFormat::NoUnderline),
2782       num_chars(numChars), chars(chars_), logClusters(0), f(font),  glyphs(g), fontEngine(fe)
2783 {
2784 }
2785
2786 QTextItemInt QTextItemInt::midItem(QFontEngine *fontEngine, int firstGlyphIndex, int numGlyphs) const
2787 {
2788     QTextItemInt ti = *this;
2789     const int end = firstGlyphIndex + numGlyphs;
2790     ti.glyphs = glyphs.mid(firstGlyphIndex, numGlyphs);
2791     ti.fontEngine = fontEngine;
2792
2793     if (logClusters && chars) {
2794         const int logClusterOffset = logClusters[0];
2795         while (logClusters[ti.chars - chars] - logClusterOffset < firstGlyphIndex)
2796             ++ti.chars;
2797
2798         ti.logClusters += (ti.chars - chars);
2799
2800         ti.num_chars = 0;
2801         int char_start = ti.chars - chars;
2802         while (char_start + ti.num_chars < num_chars && ti.logClusters[ti.num_chars] - logClusterOffset < end)
2803             ++ti.num_chars;
2804     }
2805     return ti;
2806 }
2807
2808
2809 QTransform qt_true_matrix(qreal w, qreal h, QTransform x)
2810 {
2811     QRectF rect = x.mapRect(QRectF(0, 0, w, h));
2812     return x * QTransform::fromTranslate(-rect.x(), -rect.y());
2813 }
2814
2815
2816 glyph_metrics_t glyph_metrics_t::transformed(const QTransform &matrix) const
2817 {
2818     if (matrix.type() < QTransform::TxTranslate)
2819         return *this;
2820
2821     glyph_metrics_t m = *this;
2822
2823     qreal w = width.toReal();
2824     qreal h = height.toReal();
2825     QTransform xform = qt_true_matrix(w, h, matrix);
2826
2827     QRectF rect(0, 0, w, h);
2828     rect = xform.mapRect(rect);
2829     m.width = QFixed::fromReal(rect.width());
2830     m.height = QFixed::fromReal(rect.height());
2831
2832     QLineF l = xform.map(QLineF(x.toReal(), y.toReal(), xoff.toReal(), yoff.toReal()));
2833
2834     m.x = QFixed::fromReal(l.x1());
2835     m.y = QFixed::fromReal(l.y1());
2836
2837     // The offset is relative to the baseline which is why we use dx/dy of the line
2838     m.xoff = QFixed::fromReal(l.dx());
2839     m.yoff = QFixed::fromReal(l.dy());
2840
2841     return m;
2842 }
2843
2844
2845 QT_END_NAMESPACE