1 /* 2 * Copyright (c) 2009, 2015, Oracle and/or its affiliates. All rights reserved. 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4 * 5 * This code is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 only, as 7 * published by the Free Software Foundation. Oracle designates this 8 * particular file as subject to the "Classpath" exception as provided 9 * by Oracle in the LICENSE file that accompanied this code. 10 * 11 * This code is distributed in the hope that it will be useful, but WITHOUT 12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 14 * version 2 for more details (a copy is included in the LICENSE file that 15 * accompanied this code). 16 * 17 * You should have received a copy of the GNU General Public License version 18 * 2 along with this work; if not, write to the Free Software Foundation, 19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 20 * 21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 22 * or visit www.oracle.com if you need additional information or have any 23 * questions. 24 */ 25 26 /* 27 ******************************************************************************* 28 * Copyright (C) 2001-2014, International Business Machines 29 * Corporation and others. All Rights Reserved. 30 ******************************************************************************* 31 */ 32 /* Written by Simon Montagu, Matitiahu Allouche 33 * (ported from C code written by Markus W. Scherer) 34 */ 35 36 package sun.text.bidi; 37 38 import java.text.Bidi; 39 import java.util.Arrays; 40 41 final class BidiLine { 42 43 /* 44 * General remarks about the functions in this file: 45 * 46 * These functions deal with the aspects of potentially mixed-directional 47 * text in a single paragraph or in a line of a single paragraph 48 * which has already been processed according to 49 * the Unicode 3.0 Bidi algorithm as defined in 50 * http://www.unicode.org/unicode/reports/tr9/ , version 13, 51 * also described in The Unicode Standard, Version 4.0.1 . 52 * 53 * This means that there is a Bidi object with a levels 54 * and a dirProps array. 55 * paraLevel and direction are also set. 56 * Only if the length of the text is zero, then levels==dirProps==NULL. 57 * 58 * The overall directionality of the paragraph 59 * or line is used to bypass the reordering steps if possible. 60 * Even purely RTL text does not need reordering there because 61 * the getLogical/VisualIndex() methods can compute the 62 * index on the fly in such a case. 63 * 64 * The implementation of the access to same-level-runs and of the reordering 65 * do attempt to provide better performance and less memory usage compared to 66 * a direct implementation of especially rule (L2) with an array of 67 * one (32-bit) integer per text character. 68 * 69 * Here, the levels array is scanned as soon as necessary, and a vector of 70 * same-level-runs is created. Reordering then is done on this vector. 71 * For each run of text positions that were resolved to the same level, 72 * only 8 bytes are stored: the first text position of the run and the visual 73 * position behind the run after reordering. 74 * One sign bit is used to hold the directionality of the run. 75 * This is inefficient if there are many very short runs. If the average run 76 * length is <2, then this uses more memory. 77 * 78 * In a further attempt to save memory, the levels array is never changed 79 * after all the resolution rules (Xn, Wn, Nn, In). 80 * Many methods have to consider the field trailingWSStart: 81 * if it is less than length, then there is an implicit trailing run 82 * at the paraLevel, 83 * which is not reflected in the levels array. 84 * This allows a line Bidi object to use the same levels array as 85 * its paragraph parent object. 86 * 87 * When a Bidi object is created for a line of a paragraph, then the 88 * paragraph's levels and dirProps arrays are reused by way of setting 89 * a pointer into them, not by copying. This again saves memory and forbids to 90 * change the now shared levels for (L1). 91 */ 92 93 /* handle trailing WS (L1) -------------------------------------------------- */ 94 95 /* 96 * setTrailingWSStart() sets the start index for a trailing 97 * run of WS in the line. This is necessary because we do not modify 98 * the paragraph's levels array that we just point into. 99 * Using trailingWSStart is another form of performing (L1). 100 * 101 * To make subsequent operations easier, we also include the run 102 * before the WS if it is at the paraLevel - we merge the two here. 103 * 104 * This method is called only from setLine(), so paraLevel is 105 * set correctly for the line even when contextual multiple paragraphs. 106 */ 107 setTrailingWSStart(BidiBase bidiBase)108 static void setTrailingWSStart(BidiBase bidiBase) 109 { 110 byte[] dirProps = bidiBase.dirProps; 111 byte[] levels = bidiBase.levels; 112 int start = bidiBase.length; 113 byte paraLevel = bidiBase.paraLevel; 114 115 /* If the line is terminated by a block separator, all preceding WS etc... 116 are already set to paragraph level. 117 Setting trailingWSStart to pBidi->length will avoid changing the 118 level of B chars from 0 to paraLevel in getLevels when 119 orderParagraphsLTR==TRUE 120 */ 121 if (dirProps[start - 1] == BidiBase.B) { 122 bidiBase.trailingWSStart = start; /* currently == bidiBase.length */ 123 return; 124 } 125 /* go backwards across all WS, BN, explicit codes */ 126 while (start > 0 && 127 (BidiBase.DirPropFlag(dirProps[start - 1]) & BidiBase.MASK_WS) != 0) { 128 --start; 129 } 130 131 /* if the WS run can be merged with the previous run then do so here */ 132 while (start > 0 && levels[start - 1] == paraLevel) { 133 --start; 134 } 135 136 bidiBase.trailingWSStart=start; 137 } 138 setLine(BidiBase paraBidi, Bidi newBidi, BidiBase lineBidi, int start, int limit)139 static Bidi setLine(BidiBase paraBidi, 140 Bidi newBidi, BidiBase lineBidi, 141 int start, int limit) { 142 int length; 143 144 /* set the values in lineBidi from its paraBidi parent */ 145 /* class members are already initialized to 0 */ 146 // lineBidi.paraBidi = null; /* mark unfinished setLine */ 147 // lineBidi.flags = 0; 148 // lineBidi.controlCount = 0; 149 150 length = lineBidi.length = lineBidi.originalLength = 151 lineBidi.resultLength = limit - start; 152 153 lineBidi.text = new char[length]; 154 System.arraycopy(paraBidi.text, start, lineBidi.text, 0, length); 155 lineBidi.paraLevel = paraBidi.GetParaLevelAt(start); 156 lineBidi.paraCount = paraBidi.paraCount; 157 lineBidi.runs = new BidiRun[0]; 158 lineBidi.reorderingMode = paraBidi.reorderingMode; 159 lineBidi.reorderingOptions = paraBidi.reorderingOptions; 160 if (paraBidi.controlCount > 0) { 161 int j; 162 for (j = start; j < limit; j++) { 163 if (BidiBase.IsBidiControlChar(paraBidi.text[j])) { 164 lineBidi.controlCount++; 165 } 166 } 167 lineBidi.resultLength -= lineBidi.controlCount; 168 } 169 /* copy proper subset of DirProps */ 170 lineBidi.getDirPropsMemory(length); 171 lineBidi.dirProps = lineBidi.dirPropsMemory; 172 System.arraycopy(paraBidi.dirProps, start, lineBidi.dirProps, 0, 173 length); 174 /* copy proper subset of Levels */ 175 lineBidi.getLevelsMemory(length); 176 lineBidi.levels = lineBidi.levelsMemory; 177 System.arraycopy(paraBidi.levels, start, lineBidi.levels, 0, 178 length); 179 lineBidi.runCount = -1; 180 181 if (paraBidi.direction != BidiBase.MIXED) { 182 /* the parent is already trivial */ 183 lineBidi.direction = paraBidi.direction; 184 185 /* 186 * The parent's levels are all either 187 * implicitly or explicitly ==paraLevel; 188 * do the same here. 189 */ 190 if (paraBidi.trailingWSStart <= start) { 191 lineBidi.trailingWSStart = 0; 192 } else if (paraBidi.trailingWSStart < limit) { 193 lineBidi.trailingWSStart = paraBidi.trailingWSStart - start; 194 } else { 195 lineBidi.trailingWSStart = length; 196 } 197 } else { 198 byte[] levels = lineBidi.levels; 199 int i, trailingWSStart; 200 byte level; 201 202 setTrailingWSStart(lineBidi); 203 trailingWSStart = lineBidi.trailingWSStart; 204 205 /* recalculate lineBidiBase.direction */ 206 if (trailingWSStart == 0) { 207 /* all levels are at paraLevel */ 208 lineBidi.direction = (byte)(lineBidi.paraLevel & 1); 209 } else { 210 /* get the level of the first character */ 211 level = (byte)(levels[0] & 1); 212 213 /* if there is anything of a different level, then the line 214 is mixed */ 215 if (trailingWSStart < length && 216 (lineBidi.paraLevel & 1) != level) { 217 /* the trailing WS is at paraLevel, which differs from 218 levels[0] */ 219 lineBidi.direction = BidiBase.MIXED; 220 } else { 221 /* see if levels[1..trailingWSStart-1] have the same 222 direction as levels[0] and paraLevel */ 223 for (i = 1; ; i++) { 224 if (i == trailingWSStart) { 225 /* the direction values match those in level */ 226 lineBidi.direction = level; 227 break; 228 } else if ((levels[i] & 1) != level) { 229 lineBidi.direction = BidiBase.MIXED; 230 break; 231 } 232 } 233 } 234 } 235 236 switch(lineBidi.direction) { 237 case Bidi.DIRECTION_LEFT_TO_RIGHT: 238 /* make sure paraLevel is even */ 239 lineBidi.paraLevel = (byte) 240 ((lineBidi.paraLevel + 1) & ~1); 241 242 /* all levels are implicitly at paraLevel (important for 243 getLevels()) */ 244 lineBidi.trailingWSStart = 0; 245 break; 246 case Bidi.DIRECTION_RIGHT_TO_LEFT: 247 /* make sure paraLevel is odd */ 248 lineBidi.paraLevel |= 1; 249 250 /* all levels are implicitly at paraLevel (important for 251 getLevels()) */ 252 lineBidi.trailingWSStart = 0; 253 break; 254 default: 255 break; 256 } 257 } 258 259 lineBidi.paraBidi = paraBidi; /* mark successful setLine */ 260 261 return newBidi; 262 } 263 getLevelAt(BidiBase bidiBase, int charIndex)264 static byte getLevelAt(BidiBase bidiBase, int charIndex) 265 { 266 /* return paraLevel if in the trailing WS run, otherwise the real level */ 267 if (bidiBase.direction != BidiBase.MIXED || charIndex >= bidiBase.trailingWSStart) { 268 return bidiBase.GetParaLevelAt(charIndex); 269 } else { 270 return bidiBase.levels[charIndex]; 271 } 272 } 273 getLevels(BidiBase bidiBase)274 static byte[] getLevels(BidiBase bidiBase) 275 { 276 int start = bidiBase.trailingWSStart; 277 int length = bidiBase.length; 278 279 if (start != length) { 280 /* the current levels array does not reflect the WS run */ 281 /* 282 * After the previous if(), we know that the levels array 283 * has an implicit trailing WS run and therefore does not fully 284 * reflect itself all the levels. 285 * This must be a Bidi object for a line, and 286 * we need to create a new levels array. 287 */ 288 /* bidiBase.paraLevel is ok even if contextual multiple paragraphs, 289 since bidiBase is a line object */ 290 Arrays.fill(bidiBase.levels, start, length, bidiBase.paraLevel); 291 292 /* this new levels array is set for the line and reflects the WS run */ 293 bidiBase.trailingWSStart = length; 294 } 295 if (length < bidiBase.levels.length) { 296 byte[] levels = new byte[length]; 297 System.arraycopy(bidiBase.levels, 0, levels, 0, length); 298 return levels; 299 } 300 return bidiBase.levels; 301 } 302 getVisualRun(BidiBase bidiBase, int runIndex)303 static BidiRun getVisualRun(BidiBase bidiBase, int runIndex) { 304 int start = bidiBase.runs[runIndex].start; 305 int limit; 306 byte level = bidiBase.runs[runIndex].level; 307 308 if (runIndex > 0) { 309 limit = start + 310 bidiBase.runs[runIndex].limit - 311 bidiBase.runs[runIndex - 1].limit; 312 } else { 313 limit = start + bidiBase.runs[0].limit; 314 } 315 return new BidiRun(start, limit, level); 316 } 317 318 /* in trivial cases there is only one trivial run; called by getRuns() */ getSingleRun(BidiBase bidiBase, byte level)319 private static void getSingleRun(BidiBase bidiBase, byte level) { 320 /* simple, single-run case */ 321 bidiBase.runs = bidiBase.simpleRuns; 322 bidiBase.runCount = 1; 323 324 /* fill and reorder the single run */ 325 bidiBase.runs[0] = new BidiRun(0, bidiBase.length, level); 326 } 327 328 /* reorder the runs array (L2) ---------------------------------------------- */ 329 330 /* 331 * Reorder the same-level runs in the runs array. 332 * Here, runCount>1 and maxLevel>=minLevel>=paraLevel. 333 * All the visualStart fields=logical start before reordering. 334 * The "odd" bits are not set yet. 335 * 336 * Reordering with this data structure lends itself to some handy shortcuts: 337 * 338 * Since each run is moved but not modified, and since at the initial maxLevel 339 * each sequence of same-level runs consists of only one run each, we 340 * don't need to do anything there and can predecrement maxLevel. 341 * In many simple cases, the reordering is thus done entirely in the 342 * index mapping. 343 * Also, reordering occurs only down to the lowest odd level that occurs, 344 * which is minLevel|1. However, if the lowest level itself is odd, then 345 * in the last reordering the sequence of the runs at this level or higher 346 * will be all runs, and we don't need the elaborate loop to search for them. 347 * This is covered by ++minLevel instead of minLevel|=1 followed 348 * by an extra reorder-all after the reorder-some loop. 349 * About a trailing WS run: 350 * Such a run would need special treatment because its level is not 351 * reflected in levels[] if this is not a paragraph object. 352 * Instead, all characters from trailingWSStart on are implicitly at 353 * paraLevel. 354 * However, for all maxLevel>paraLevel, this run will never be reordered 355 * and does not need to be taken into account. maxLevel==paraLevel is only reordered 356 * if minLevel==paraLevel is odd, which is done in the extra segment. 357 * This means that for the main reordering loop we don't need to consider 358 * this run and can --runCount. If it is later part of the all-runs 359 * reordering, then runCount is adjusted accordingly. 360 */ reorderLine(BidiBase bidiBase, byte minLevel, byte maxLevel)361 private static void reorderLine(BidiBase bidiBase, byte minLevel, byte maxLevel) { 362 363 /* nothing to do? */ 364 if (maxLevel<=(minLevel|1)) { 365 return; 366 } 367 368 BidiRun[] runs; 369 BidiRun tempRun; 370 byte[] levels; 371 int firstRun, endRun, limitRun, runCount; 372 373 /* 374 * Reorder only down to the lowest odd level 375 * and reorder at an odd minLevel in a separate, simpler loop. 376 * See comments above for why minLevel is always incremented. 377 */ 378 ++minLevel; 379 380 runs = bidiBase.runs; 381 levels = bidiBase.levels; 382 runCount = bidiBase.runCount; 383 384 /* do not include the WS run at paraLevel<=old minLevel except in the simple loop */ 385 if (bidiBase.trailingWSStart < bidiBase.length) { 386 --runCount; 387 } 388 389 while (--maxLevel >= minLevel) { 390 firstRun = 0; 391 392 /* loop for all sequences of runs */ 393 for ( ; ; ) { 394 /* look for a sequence of runs that are all at >=maxLevel */ 395 /* look for the first run of such a sequence */ 396 while (firstRun < runCount && levels[runs[firstRun].start] < maxLevel) { 397 ++firstRun; 398 } 399 if (firstRun >= runCount) { 400 break; /* no more such runs */ 401 } 402 403 /* look for the limit run of such a sequence (the run behind it) */ 404 for (limitRun = firstRun; ++limitRun < runCount && 405 levels[runs[limitRun].start]>=maxLevel; ) {} 406 407 /* Swap the entire sequence of runs from firstRun to limitRun-1. */ 408 endRun = limitRun - 1; 409 while (firstRun < endRun) { 410 tempRun = runs[firstRun]; 411 runs[firstRun] = runs[endRun]; 412 runs[endRun] = tempRun; 413 ++firstRun; 414 --endRun; 415 } 416 417 if (limitRun == runCount) { 418 break; /* no more such runs */ 419 } else { 420 firstRun = limitRun + 1; 421 } 422 } 423 } 424 425 /* now do maxLevel==old minLevel (==odd!), see above */ 426 if ((minLevel & 1) == 0) { 427 firstRun = 0; 428 429 /* include the trailing WS run in this complete reordering */ 430 if (bidiBase.trailingWSStart == bidiBase.length) { 431 --runCount; 432 } 433 434 /* Swap the entire sequence of all runs. (endRun==runCount) */ 435 while (firstRun < runCount) { 436 tempRun = runs[firstRun]; 437 runs[firstRun] = runs[runCount]; 438 runs[runCount] = tempRun; 439 ++firstRun; 440 --runCount; 441 } 442 } 443 } 444 445 /* compute the runs array --------------------------------------------------- */ 446 getRunFromLogicalIndex(BidiBase bidiBase, int logicalIndex)447 static int getRunFromLogicalIndex(BidiBase bidiBase, int logicalIndex) { 448 BidiRun[] runs = bidiBase.runs; 449 int runCount = bidiBase.runCount, visualStart = 0, i, length, logicalStart; 450 451 for (i = 0; i < runCount; i++) { 452 length = runs[i].limit - visualStart; 453 logicalStart = runs[i].start; 454 if ((logicalIndex >= logicalStart) && (logicalIndex < (logicalStart+length))) { 455 return i; 456 } 457 visualStart += length; 458 } 459 /* we should never get here */ 460 throw new IllegalStateException("Internal ICU error in getRunFromLogicalIndex"); 461 } 462 463 /* 464 * Compute the runs array from the levels array. 465 * After getRuns() returns true, runCount is guaranteed to be >0 466 * and the runs are reordered. 467 * Odd-level runs have visualStart on their visual right edge and 468 * they progress visually to the left. 469 * If option OPTION_INSERT_MARKS is set, insertRemove will contain the 470 * sum of appropriate LRM/RLM_BEFORE/AFTER flags. 471 * If option OPTION_REMOVE_CONTROLS is set, insertRemove will contain the 472 * negative number of BiDi control characters within this run. 473 */ getRuns(BidiBase bidiBase)474 static void getRuns(BidiBase bidiBase) { 475 /* 476 * This method returns immediately if the runs are already set. This 477 * includes the case of length==0 (handled in setPara).. 478 */ 479 if (bidiBase.runCount >= 0) { 480 return; 481 } 482 if (bidiBase.direction != BidiBase.MIXED) { 483 /* simple, single-run case - this covers length==0 */ 484 /* bidiBase.paraLevel is ok even for contextual multiple paragraphs */ 485 getSingleRun(bidiBase, bidiBase.paraLevel); 486 } else /* BidiBase.MIXED, length>0 */ { 487 /* mixed directionality */ 488 int length = bidiBase.length, limit; 489 byte[] levels = bidiBase.levels; 490 int i, runCount; 491 byte level = -1; /* initialize with no valid level */ 492 /* 493 * If there are WS characters at the end of the line 494 * and the run preceding them has a level different from 495 * paraLevel, then they will form their own run at paraLevel (L1). 496 * Count them separately. 497 * We need some special treatment for this in order to not 498 * modify the levels array which a line Bidi object shares 499 * with its paragraph parent and its other line siblings. 500 * In other words, for the trailing WS, it may be 501 * levels[]!=paraLevel but we have to treat it like it were so. 502 */ 503 limit = bidiBase.trailingWSStart; 504 /* count the runs, there is at least one non-WS run, and limit>0 */ 505 runCount = 0; 506 for (i = 0; i < limit; ++i) { 507 /* increment runCount at the start of each run */ 508 if (levels[i] != level) { 509 ++runCount; 510 level = levels[i]; 511 } 512 } 513 514 /* 515 * We don't need to see if the last run can be merged with a trailing 516 * WS run because setTrailingWSStart() would have done that. 517 */ 518 if (runCount == 1 && limit == length) { 519 /* There is only one non-WS run and no trailing WS-run. */ 520 getSingleRun(bidiBase, levels[0]); 521 } else /* runCount>1 || limit<length */ { 522 /* allocate and set the runs */ 523 BidiRun[] runs; 524 int runIndex, start; 525 byte minLevel = BidiBase.MAX_EXPLICIT_LEVEL + 1; 526 byte maxLevel=0; 527 528 /* now, count a (non-mergeable) WS run */ 529 if (limit < length) { 530 ++runCount; 531 } 532 533 /* runCount > 1 */ 534 bidiBase.getRunsMemory(runCount); 535 runs = bidiBase.runsMemory; 536 537 /* set the runs */ 538 /* FOOD FOR THOUGHT: this could be optimized, e.g.: 539 * 464->444, 484->444, 575->555, 595->555 540 * However, that would take longer. Check also how it would 541 * interact with BiDi control removal and inserting Marks. 542 */ 543 runIndex = 0; 544 545 /* search for the run limits and initialize visualLimit values with the run lengths */ 546 i = 0; 547 do { 548 /* prepare this run */ 549 start = i; 550 level = levels[i]; 551 if (level < minLevel) { 552 minLevel = level; 553 } 554 if (level > maxLevel) { 555 maxLevel = level; 556 } 557 558 /* look for the run limit */ 559 while (++i < limit && levels[i] == level) {} 560 561 /* i is another run limit */ 562 runs[runIndex] = new BidiRun(start, i - start, level); 563 ++runIndex; 564 } while (i < limit); 565 566 if (limit < length) { 567 /* there is a separate WS run */ 568 runs[runIndex] = new BidiRun(limit, length - limit, bidiBase.paraLevel); 569 /* For the trailing WS run, bidiBase.paraLevel is ok even 570 if contextual multiple paragraphs. */ 571 if (bidiBase.paraLevel < minLevel) { 572 minLevel = bidiBase.paraLevel; 573 } 574 } 575 576 /* set the object fields */ 577 bidiBase.runs = runs; 578 bidiBase.runCount = runCount; 579 580 reorderLine(bidiBase, minLevel, maxLevel); 581 582 /* now add the direction flags and adjust the visualLimit's to be just that */ 583 /* this loop will also handle the trailing WS run */ 584 limit = 0; 585 for (i = 0; i < runCount; ++i) { 586 runs[i].level = levels[runs[i].start]; 587 limit = (runs[i].limit += limit); 588 } 589 590 /* Set the embedding level for the trailing WS run. */ 591 /* For a RTL paragraph, it will be the *first* run in visual order. */ 592 /* For the trailing WS run, bidiBase.paraLevel is ok even if 593 contextual multiple paragraphs. */ 594 if (runIndex < runCount) { 595 int trailingRun = ((bidiBase.paraLevel & 1) != 0)? 0 : runIndex; 596 runs[trailingRun].level = bidiBase.paraLevel; 597 } 598 } 599 } 600 601 /* handle insert LRM/RLM BEFORE/AFTER run */ 602 if (bidiBase.insertPoints.size > 0) { 603 BidiBase.Point point; 604 int runIndex, ip; 605 for (ip = 0; ip < bidiBase.insertPoints.size; ip++) { 606 point = bidiBase.insertPoints.points[ip]; 607 runIndex = getRunFromLogicalIndex(bidiBase, point.pos); 608 bidiBase.runs[runIndex].insertRemove |= point.flag; 609 } 610 } 611 612 /* handle remove BiDi control characters */ 613 if (bidiBase.controlCount > 0) { 614 int runIndex, ic; 615 char c; 616 for (ic = 0; ic < bidiBase.length; ic++) { 617 c = bidiBase.text[ic]; 618 if (BidiBase.IsBidiControlChar(c)) { 619 runIndex = getRunFromLogicalIndex(bidiBase, ic); 620 bidiBase.runs[runIndex].insertRemove--; 621 } 622 } 623 } 624 } 625 prepareReorder(byte[] levels, byte[] pMinLevel, byte[] pMaxLevel)626 static int[] prepareReorder(byte[] levels, byte[] pMinLevel, byte[] pMaxLevel) 627 { 628 int start; 629 byte level, minLevel, maxLevel; 630 631 if (levels == null || levels.length <= 0) { 632 return null; 633 } 634 635 /* determine minLevel and maxLevel */ 636 minLevel = BidiBase.MAX_EXPLICIT_LEVEL + 1; 637 maxLevel = 0; 638 for (start = levels.length; start>0; ) { 639 level = levels[--start]; 640 if (level < 0 || level > (BidiBase.MAX_EXPLICIT_LEVEL + 1)) { 641 return null; 642 } 643 if (level < minLevel) { 644 minLevel = level; 645 } 646 if (level > maxLevel) { 647 maxLevel = level; 648 } 649 } 650 pMinLevel[0] = minLevel; 651 pMaxLevel[0] = maxLevel; 652 653 /* initialize the index map */ 654 int[] indexMap = new int[levels.length]; 655 for (start = levels.length; start > 0; ) { 656 --start; 657 indexMap[start] = start; 658 } 659 660 return indexMap; 661 } 662 reorderVisual(byte[] levels)663 static int[] reorderVisual(byte[] levels) 664 { 665 byte[] aMinLevel = new byte[1]; 666 byte[] aMaxLevel = new byte[1]; 667 int start, end, limit, temp; 668 byte minLevel, maxLevel; 669 670 int[] indexMap = prepareReorder(levels, aMinLevel, aMaxLevel); 671 if (indexMap == null) { 672 return null; 673 } 674 675 minLevel = aMinLevel[0]; 676 maxLevel = aMaxLevel[0]; 677 678 /* nothing to do? */ 679 if (minLevel == maxLevel && (minLevel & 1) == 0) { 680 return indexMap; 681 } 682 683 /* reorder only down to the lowest odd level */ 684 minLevel |= 1; 685 686 /* loop maxLevel..minLevel */ 687 do { 688 start = 0; 689 690 /* loop for all sequences of levels to reorder at the current maxLevel */ 691 for ( ; ; ) { 692 /* look for a sequence of levels that are all at >=maxLevel */ 693 /* look for the first index of such a sequence */ 694 while (start < levels.length && levels[start] < maxLevel) { 695 ++start; 696 } 697 if (start >= levels.length) { 698 break; /* no more such runs */ 699 } 700 701 /* look for the limit of such a sequence (the index behind it) */ 702 for (limit = start; ++limit < levels.length && levels[limit] >= maxLevel; ) {} 703 704 /* 705 * Swap the entire interval of indexes from start to limit-1. 706 * We don't need to swap the levels for the purpose of this 707 * algorithm: the sequence of levels that we look at does not 708 * move anyway. 709 */ 710 end = limit - 1; 711 while (start < end) { 712 temp = indexMap[start]; 713 indexMap[start] = indexMap[end]; 714 indexMap[end] = temp; 715 716 ++start; 717 --end; 718 } 719 720 if (limit == levels.length) { 721 break; /* no more such sequences */ 722 } else { 723 start = limit + 1; 724 } 725 } 726 } while (--maxLevel >= minLevel); 727 728 return indexMap; 729 } 730 getVisualMap(BidiBase bidiBase)731 static int[] getVisualMap(BidiBase bidiBase) 732 { 733 /* fill a visual-to-logical index map using the runs[] */ 734 BidiRun[] runs = bidiBase.runs; 735 int logicalStart, visualStart, visualLimit; 736 int allocLength = bidiBase.length > bidiBase.resultLength ? bidiBase.length 737 : bidiBase.resultLength; 738 int[] indexMap = new int[allocLength]; 739 740 visualStart = 0; 741 int idx = 0; 742 for (int j = 0; j < bidiBase.runCount; ++j) { 743 logicalStart = runs[j].start; 744 visualLimit = runs[j].limit; 745 if (runs[j].isEvenRun()) { 746 do { /* LTR */ 747 indexMap[idx++] = logicalStart++; 748 } while (++visualStart < visualLimit); 749 } else { 750 logicalStart += visualLimit - visualStart; /* logicalLimit */ 751 do { /* RTL */ 752 indexMap[idx++] = --logicalStart; 753 } while (++visualStart < visualLimit); 754 } 755 /* visualStart==visualLimit; */ 756 } 757 758 if (bidiBase.insertPoints.size > 0) { 759 int markFound = 0, runCount = bidiBase.runCount; 760 int insertRemove, i, j, k; 761 runs = bidiBase.runs; 762 /* count all inserted marks */ 763 for (i = 0; i < runCount; i++) { 764 insertRemove = runs[i].insertRemove; 765 if ((insertRemove & (BidiBase.LRM_BEFORE|BidiBase.RLM_BEFORE)) > 0) { 766 markFound++; 767 } 768 if ((insertRemove & (BidiBase.LRM_AFTER|BidiBase.RLM_AFTER)) > 0) { 769 markFound++; 770 } 771 } 772 /* move back indexes by number of preceding marks */ 773 k = bidiBase.resultLength; 774 for (i = runCount - 1; i >= 0 && markFound > 0; i--) { 775 insertRemove = runs[i].insertRemove; 776 if ((insertRemove & (BidiBase.LRM_AFTER|BidiBase.RLM_AFTER)) > 0) { 777 indexMap[--k] = BidiBase.MAP_NOWHERE; 778 markFound--; 779 } 780 visualStart = i > 0 ? runs[i-1].limit : 0; 781 for (j = runs[i].limit - 1; j >= visualStart && markFound > 0; j--) { 782 indexMap[--k] = indexMap[j]; 783 } 784 if ((insertRemove & (BidiBase.LRM_BEFORE|BidiBase.RLM_BEFORE)) > 0) { 785 indexMap[--k] = BidiBase.MAP_NOWHERE; 786 markFound--; 787 } 788 } 789 } 790 else if (bidiBase.controlCount > 0) { 791 int runCount = bidiBase.runCount, logicalEnd; 792 int insertRemove, length, i, j, k, m; 793 char uchar; 794 boolean evenRun; 795 runs = bidiBase.runs; 796 visualStart = 0; 797 /* move forward indexes by number of preceding controls */ 798 k = 0; 799 for (i = 0; i < runCount; i++, visualStart += length) { 800 length = runs[i].limit - visualStart; 801 insertRemove = runs[i].insertRemove; 802 /* if no control found yet, nothing to do in this run */ 803 if ((insertRemove == 0) && (k == visualStart)) { 804 k += length; 805 continue; 806 } 807 /* if no control in this run */ 808 if (insertRemove == 0) { 809 visualLimit = runs[i].limit; 810 for (j = visualStart; j < visualLimit; j++) { 811 indexMap[k++] = indexMap[j]; 812 } 813 continue; 814 } 815 logicalStart = runs[i].start; 816 evenRun = runs[i].isEvenRun(); 817 logicalEnd = logicalStart + length - 1; 818 for (j = 0; j < length; j++) { 819 m = evenRun ? logicalStart + j : logicalEnd - j; 820 uchar = bidiBase.text[m]; 821 if (!BidiBase.IsBidiControlChar(uchar)) { 822 indexMap[k++] = m; 823 } 824 } 825 } 826 } 827 if (allocLength == bidiBase.resultLength) { 828 return indexMap; 829 } 830 int[] newMap = new int[bidiBase.resultLength]; 831 System.arraycopy(indexMap, 0, newMap, 0, bidiBase.resultLength); 832 return newMap; 833 } 834 835 } 836