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1 /*
2  * (C) Copyright IBM Corp. and others 1998-2013 - All Rights Reserved
3  */
4 
5 #include "LETypes.h"
6 #include "LEScripts.h"
7 #include "LELanguages.h"
8 #include "LESwaps.h"
9 
10 #include "LayoutEngine.h"
11 #include "ArabicLayoutEngine.h"
12 #include "CanonShaping.h"
13 #include "HanLayoutEngine.h"
14 #include "HangulLayoutEngine.h"
15 #include "IndicLayoutEngine.h"
16 #include "KhmerLayoutEngine.h"
17 #include "ThaiLayoutEngine.h"
18 #include "TibetanLayoutEngine.h"
19 #include "GXLayoutEngine.h"
20 #include "GXLayoutEngine2.h"
21 
22 #include "ScriptAndLanguageTags.h"
23 #include "CharSubstitutionFilter.h"
24 
25 #include "LEGlyphStorage.h"
26 
27 #include "OpenTypeUtilities.h"
28 #include "GlyphSubstitutionTables.h"
29 #include "GlyphDefinitionTables.h"
30 #include "MorphTables.h"
31 
32 #include "DefaultCharMapper.h"
33 
34 #include "KernTable.h"
35 
36 U_NAMESPACE_BEGIN
37 
38 /* Leave this copyright notice here! It needs to go somewhere in this library. */
39 static const char copyright[] = U_COPYRIGHT_STRING;
40 
41 /* TODO: remove these? */
42 const le_int32 LayoutEngine::kTypoFlagKern = LE_Kerning_FEATURE_FLAG;
43 const le_int32 LayoutEngine::kTypoFlagLiga = LE_Ligatures_FEATURE_FLAG;
44 
45 const LEUnicode32 DefaultCharMapper::controlChars[] = {
46     0x0009, 0x000A, 0x000D,
47     /*0x200C, 0x200D,*/ 0x200E, 0x200F,
48     0x2028, 0x2029, 0x202A, 0x202B, 0x202C, 0x202D, 0x202E,
49     0x206A, 0x206B, 0x206C, 0x206D, 0x206E, 0x206F
50 };
51 
52 const le_int32 DefaultCharMapper::controlCharsCount = LE_ARRAY_SIZE(controlChars);
53 
mapChar(LEUnicode32 ch) const54 LEUnicode32 DefaultCharMapper::mapChar(LEUnicode32 ch) const
55 {
56     if (fFilterControls) {
57         le_int32 index = OpenTypeUtilities::search((le_uint32)ch, (le_uint32 *)controlChars, controlCharsCount);
58 
59         if (controlChars[index] == ch) {
60             return 0xFFFF;
61         }
62     }
63 
64     if (fMirror) {
65         le_int32 index = OpenTypeUtilities::search((le_uint32) ch, (le_uint32 *)DefaultCharMapper::mirroredChars, DefaultCharMapper::mirroredCharsCount);
66 
67         if (mirroredChars[index] == ch) {
68             return DefaultCharMapper::srahCderorrim[index];
69         }
70     }
71 
72     return ch;
73 }
74 
75 // This is here to get it out of LEGlyphFilter.h.
76 // No particular reason to put it here, other than
77 // this is a good central location...
~LEGlyphFilter()78 LEGlyphFilter::~LEGlyphFilter()
79 {
80     // nothing to do
81 }
82 
CharSubstitutionFilter(const LEFontInstance * fontInstance)83 CharSubstitutionFilter::CharSubstitutionFilter(const LEFontInstance *fontInstance)
84   : fFontInstance(fontInstance)
85 {
86     // nothing to do
87 }
88 
~CharSubstitutionFilter()89 CharSubstitutionFilter::~CharSubstitutionFilter()
90 {
91     // nothing to do
92 }
93 
94 class CanonMarkFilter : public UMemory, public LEGlyphFilter
95 {
96 private:
97     const GlyphClassDefinitionTable *classDefTable;
98 
99     CanonMarkFilter(const CanonMarkFilter &other); // forbid copying of this class
100     CanonMarkFilter &operator=(const CanonMarkFilter &other); // forbid copying of this class
101 
102 public:
103     CanonMarkFilter(const GlyphDefinitionTableHeader *gdefTable);
104     virtual ~CanonMarkFilter();
105 
106     virtual le_bool accept(LEGlyphID glyph) const;
107 };
108 
CanonMarkFilter(const GlyphDefinitionTableHeader * gdefTable)109 CanonMarkFilter::CanonMarkFilter(const GlyphDefinitionTableHeader *gdefTable)
110 {
111     classDefTable = gdefTable->getMarkAttachClassDefinitionTable();
112 }
113 
~CanonMarkFilter()114 CanonMarkFilter::~CanonMarkFilter()
115 {
116     // nothing to do?
117 }
118 
accept(LEGlyphID glyph) const119 le_bool CanonMarkFilter::accept(LEGlyphID glyph) const
120 {
121     le_int32 glyphClass = classDefTable->getGlyphClass(glyph);
122 
123     return glyphClass != 0;
124 }
125 
126 UOBJECT_DEFINE_RTTI_IMPLEMENTATION(LayoutEngine)
127 
128 #define ccmpFeatureTag  LE_CCMP_FEATURE_TAG
129 
130 #define ccmpFeatureMask 0x80000000UL
131 
132 #define canonFeatures (ccmpFeatureMask)
133 
134 static const FeatureMap canonFeatureMap[] =
135 {
136     {ccmpFeatureTag, ccmpFeatureMask}
137 };
138 
139 static const le_int32 canonFeatureMapCount = LE_ARRAY_SIZE(canonFeatureMap);
140 
LayoutEngine(const LEFontInstance * fontInstance,le_int32 scriptCode,le_int32 languageCode,le_int32 typoFlags,LEErrorCode & success)141 LayoutEngine::LayoutEngine(const LEFontInstance *fontInstance,
142                            le_int32 scriptCode,
143                            le_int32 languageCode,
144                            le_int32 typoFlags,
145                            LEErrorCode &success)
146   : fGlyphStorage(NULL), fFontInstance(fontInstance), fScriptCode(scriptCode), fLanguageCode(languageCode),
147     fTypoFlags(typoFlags), fFilterZeroWidth(TRUE)
148 {
149     if (LE_FAILURE(success)) {
150         return;
151     }
152 
153     fGlyphStorage = new LEGlyphStorage();
154     if (fGlyphStorage == NULL) {
155         success = LE_MEMORY_ALLOCATION_ERROR;
156     }
157 }
158 
getGlyphCount() const159 le_int32 LayoutEngine::getGlyphCount() const
160 {
161     return fGlyphStorage->getGlyphCount();
162 }
163 
getCharIndices(le_int32 charIndices[],le_int32 indexBase,LEErrorCode & success) const164 void LayoutEngine::getCharIndices(le_int32 charIndices[], le_int32 indexBase, LEErrorCode &success) const
165 {
166     fGlyphStorage->getCharIndices(charIndices, indexBase, success);
167 }
168 
getCharIndices(le_int32 charIndices[],LEErrorCode & success) const169 void LayoutEngine::getCharIndices(le_int32 charIndices[], LEErrorCode &success) const
170 {
171     fGlyphStorage->getCharIndices(charIndices, success);
172 }
173 
174 // Copy the glyphs into caller's (32-bit) glyph array, OR in extraBits
getGlyphs(le_uint32 glyphs[],le_uint32 extraBits,LEErrorCode & success) const175 void LayoutEngine::getGlyphs(le_uint32 glyphs[], le_uint32 extraBits, LEErrorCode &success) const
176 {
177     fGlyphStorage->getGlyphs(glyphs, extraBits, success);
178 }
179 
getGlyphs(LEGlyphID glyphs[],LEErrorCode & success) const180 void LayoutEngine::getGlyphs(LEGlyphID glyphs[], LEErrorCode &success) const
181 {
182     fGlyphStorage->getGlyphs(glyphs, success);
183 }
184 
185 
getGlyphPositions(float positions[],LEErrorCode & success) const186 void LayoutEngine::getGlyphPositions(float positions[], LEErrorCode &success) const
187 {
188     fGlyphStorage->getGlyphPositions(positions, success);
189 }
190 
getGlyphPosition(le_int32 glyphIndex,float & x,float & y,LEErrorCode & success) const191 void LayoutEngine::getGlyphPosition(le_int32 glyphIndex, float &x, float &y, LEErrorCode &success) const
192 {
193     fGlyphStorage->getGlyphPosition(glyphIndex, x, y, success);
194 }
195 
characterProcessing(const LEUnicode chars[],le_int32 offset,le_int32 count,le_int32 max,le_bool rightToLeft,LEUnicode * & outChars,LEGlyphStorage & glyphStorage,LEErrorCode & success)196 le_int32 LayoutEngine::characterProcessing(const LEUnicode chars[], le_int32 offset, le_int32 count, le_int32 max, le_bool rightToLeft,
197                 LEUnicode *&outChars, LEGlyphStorage &glyphStorage, LEErrorCode &success)
198 {
199     if (LE_FAILURE(success)) {
200         return 0;
201     }
202 
203     if (offset < 0 || count < 0 || max < 0 || offset >= max || offset + count > max) {
204         success = LE_ILLEGAL_ARGUMENT_ERROR;
205         return 0;
206     }
207 
208     const GlyphSubstitutionTableHeader *canonGSUBTable = (GlyphSubstitutionTableHeader *) CanonShaping::glyphSubstitutionTable;
209     LETag scriptTag  = OpenTypeLayoutEngine::getScriptTag(fScriptCode);
210     LETag langSysTag = OpenTypeLayoutEngine::getLangSysTag(fLanguageCode);
211     le_int32 i, dir = 1, out = 0, outCharCount = count;
212 
213     if (canonGSUBTable->coversScript(scriptTag)) {
214         CharSubstitutionFilter *substitutionFilter = new CharSubstitutionFilter(fFontInstance);
215         if (substitutionFilter == NULL) {
216             success = LE_MEMORY_ALLOCATION_ERROR;
217             return 0;
218         }
219 
220 		const LEUnicode *inChars = &chars[offset];
221 		LEUnicode *reordered = NULL;
222         LEGlyphStorage fakeGlyphStorage;
223 
224         fakeGlyphStorage.allocateGlyphArray(count, rightToLeft, success);
225 
226         if (LE_FAILURE(success)) {
227             delete substitutionFilter;
228             return 0;
229         }
230 
231 		// This is the cheapest way to get mark reordering only for Hebrew.
232 		// We could just do the mark reordering for all scripts, but most
233 		// of them probably don't need it...
234 		if (fScriptCode == hebrScriptCode) {
235 			reordered = LE_NEW_ARRAY(LEUnicode, count);
236 
237 			if (reordered == NULL) {
238                 delete substitutionFilter;
239 				success = LE_MEMORY_ALLOCATION_ERROR;
240 				return 0;
241 			}
242 
243 			CanonShaping::reorderMarks(&chars[offset], count, rightToLeft, reordered, fakeGlyphStorage);
244 			inChars = reordered;
245         }
246 
247         fakeGlyphStorage.allocateAuxData(success);
248 
249         if (LE_FAILURE(success)) {
250             delete substitutionFilter;
251             return 0;
252         }
253 
254         if (rightToLeft) {
255             out = count - 1;
256             dir = -1;
257         }
258 
259         for (i = 0; i < count; i += 1, out += dir) {
260             fakeGlyphStorage[out] = (LEGlyphID) inChars[i];
261             fakeGlyphStorage.setAuxData(out, canonFeatures, success);
262         }
263 
264 		if (reordered != NULL) {
265 			LE_DELETE_ARRAY(reordered);
266 		}
267 
268         outCharCount = canonGSUBTable->process(fakeGlyphStorage, rightToLeft, scriptTag, langSysTag, NULL, substitutionFilter, canonFeatureMap, canonFeatureMapCount, FALSE, success);
269 
270         if (LE_FAILURE(success)) {
271             delete substitutionFilter;
272             return 0;
273         }
274 
275         out = (rightToLeft? outCharCount - 1 : 0);
276 
277         /*
278          * The char indices array in fakeGlyphStorage has the correct mapping
279          * back to the original input characters. Save it in glyphStorage. The
280          * subsequent call to glyphStoratge.allocateGlyphArray will keep this
281          * array rather than allocating and initializing a new one.
282          */
283         glyphStorage.adoptCharIndicesArray(fakeGlyphStorage);
284 
285         outChars = LE_NEW_ARRAY(LEUnicode, outCharCount);
286 
287         if (outChars == NULL) {
288             delete substitutionFilter;
289             success = LE_MEMORY_ALLOCATION_ERROR;
290             return 0;
291         }
292 
293         for (i = 0; i < outCharCount; i += 1, out += dir) {
294             outChars[out] = (LEUnicode) LE_GET_GLYPH(fakeGlyphStorage[i]);
295         }
296 
297         delete substitutionFilter;
298     }
299 
300     return outCharCount;
301 }
302 
computeGlyphs(const LEUnicode chars[],le_int32 offset,le_int32 count,le_int32 max,le_bool rightToLeft,LEGlyphStorage & glyphStorage,LEErrorCode & success)303 le_int32 LayoutEngine::computeGlyphs(const LEUnicode chars[], le_int32 offset, le_int32 count, le_int32 max, le_bool rightToLeft,
304                                             LEGlyphStorage &glyphStorage, LEErrorCode &success)
305 {
306     if (LE_FAILURE(success)) {
307         return 0;
308     }
309 
310     if (chars == NULL || offset < 0 || count < 0 || max < 0 || offset >= max || offset + count > max) {
311         success = LE_ILLEGAL_ARGUMENT_ERROR;
312         return 0;
313     }
314 
315     LEUnicode *outChars = NULL;
316     le_int32 outCharCount = characterProcessing(chars, offset, count, max, rightToLeft, outChars, glyphStorage, success);
317 
318     if (outChars != NULL) {
319         mapCharsToGlyphs(outChars, 0, outCharCount, rightToLeft, rightToLeft, glyphStorage, success);
320         LE_DELETE_ARRAY(outChars); // FIXME: a subclass may have allocated this, in which case this delete might not work...
321     } else {
322         mapCharsToGlyphs(chars, offset, count, rightToLeft, rightToLeft, glyphStorage, success);
323     }
324 
325     return glyphStorage.getGlyphCount();
326 }
327 
328 // Input: glyphs
329 // Output: positions
positionGlyphs(LEGlyphStorage & glyphStorage,float x,float y,LEErrorCode & success)330 void LayoutEngine::positionGlyphs(LEGlyphStorage &glyphStorage, float x, float y, LEErrorCode &success)
331 {
332     if (LE_FAILURE(success)) {
333         return;
334     }
335 
336     glyphStorage.allocatePositions(success);
337 
338     if (LE_FAILURE(success)) {
339         return;
340     }
341 
342     le_int32 i, glyphCount = glyphStorage.getGlyphCount();
343 
344     for (i = 0; i < glyphCount; i += 1) {
345         LEPoint advance;
346 
347         glyphStorage.setPosition(i, x, y, success);
348 
349         fFontInstance->getGlyphAdvance(glyphStorage[i], advance);
350         x += advance.fX;
351         y += advance.fY;
352     }
353 
354     glyphStorage.setPosition(glyphCount, x, y, success);
355 }
356 
adjustGlyphPositions(const LEUnicode chars[],le_int32 offset,le_int32 count,le_bool reverse,LEGlyphStorage & glyphStorage,LEErrorCode & success)357 void LayoutEngine::adjustGlyphPositions(const LEUnicode chars[], le_int32 offset, le_int32 count, le_bool  reverse,
358                                         LEGlyphStorage &glyphStorage, LEErrorCode &success)
359 {
360     if (LE_FAILURE(success)) {
361         return;
362     }
363 
364     if (chars == NULL || offset < 0 || count < 0) {
365         success = LE_ILLEGAL_ARGUMENT_ERROR;
366         return;
367     }
368 
369     GlyphDefinitionTableHeader *gdefTable = (GlyphDefinitionTableHeader *) CanonShaping::glyphDefinitionTable;
370     CanonMarkFilter filter(gdefTable);
371 
372     adjustMarkGlyphs(&chars[offset], count, reverse, glyphStorage, &filter, success);
373 
374     if (fTypoFlags & 0x1) { /* kerning enabled */
375       static const le_uint32 kernTableTag = LE_KERN_TABLE_TAG;
376 
377       KernTable kt(fFontInstance, getFontTable(kernTableTag));
378       kt.process(glyphStorage);
379     }
380 
381     // default is no adjustments
382     return;
383 }
384 
adjustMarkGlyphs(LEGlyphStorage & glyphStorage,LEGlyphFilter * markFilter,LEErrorCode & success)385 void LayoutEngine::adjustMarkGlyphs(LEGlyphStorage &glyphStorage, LEGlyphFilter *markFilter, LEErrorCode &success)
386 {
387     float xAdjust = 0;
388     le_int32 p, glyphCount = glyphStorage.getGlyphCount();
389 
390     if (LE_FAILURE(success)) {
391         return;
392     }
393 
394     if (markFilter == NULL) {
395         success = LE_ILLEGAL_ARGUMENT_ERROR;
396         return;
397     }
398 
399     float ignore, prev;
400 
401     glyphStorage.getGlyphPosition(0, prev, ignore, success);
402 
403     for (p = 0; p < glyphCount; p += 1) {
404         float next, xAdvance;
405 
406         glyphStorage.getGlyphPosition(p + 1, next, ignore, success);
407 
408         xAdvance = next - prev;
409         glyphStorage.adjustPosition(p, xAdjust, 0, success);
410 
411         if (markFilter->accept(glyphStorage[p])) {
412             xAdjust -= xAdvance;
413         }
414 
415         prev = next;
416     }
417 
418     glyphStorage.adjustPosition(glyphCount, xAdjust, 0, success);
419 }
420 
adjustMarkGlyphs(const LEUnicode chars[],le_int32 charCount,le_bool reverse,LEGlyphStorage & glyphStorage,LEGlyphFilter * markFilter,LEErrorCode & success)421 void LayoutEngine::adjustMarkGlyphs(const LEUnicode chars[], le_int32 charCount, le_bool reverse, LEGlyphStorage &glyphStorage, LEGlyphFilter *markFilter, LEErrorCode &success)
422 {
423     float xAdjust = 0;
424     le_int32 c = 0, direction = 1, p;
425     le_int32 glyphCount = glyphStorage.getGlyphCount();
426 
427     if (LE_FAILURE(success)) {
428         return;
429     }
430 
431     if (markFilter == NULL) {
432         success = LE_ILLEGAL_ARGUMENT_ERROR;
433         return;
434     }
435 
436     if (reverse) {
437         c = glyphCount - 1;
438         direction = -1;
439     }
440 
441     float ignore, prev;
442 
443     glyphStorage.getGlyphPosition(0, prev, ignore, success);
444 
445     for (p = 0; p < charCount; p += 1, c += direction) {
446         float next, xAdvance;
447 
448         glyphStorage.getGlyphPosition(p + 1, next, ignore, success);
449 
450         xAdvance = next - prev;
451         glyphStorage.adjustPosition(p, xAdjust, 0, success);
452 
453         if (markFilter->accept(chars[c])) {
454             xAdjust -= xAdvance;
455         }
456 
457         prev = next;
458     }
459 
460     glyphStorage.adjustPosition(glyphCount, xAdjust, 0, success);
461 }
462 
getFontTable(LETag tableTag) const463 const void *LayoutEngine::getFontTable(LETag tableTag) const
464 {
465     return fFontInstance->getFontTable(tableTag);
466 }
467 
mapCharsToGlyphs(const LEUnicode chars[],le_int32 offset,le_int32 count,le_bool reverse,le_bool mirror,LEGlyphStorage & glyphStorage,LEErrorCode & success)468 void LayoutEngine::mapCharsToGlyphs(const LEUnicode chars[], le_int32 offset, le_int32 count, le_bool reverse, le_bool mirror,
469                                     LEGlyphStorage &glyphStorage, LEErrorCode &success)
470 {
471     if (LE_FAILURE(success)) {
472         return;
473     }
474 
475     glyphStorage.allocateGlyphArray(count, reverse, success);
476 
477     DefaultCharMapper charMapper(TRUE, mirror);
478 
479     fFontInstance->mapCharsToGlyphs(chars, offset, count, reverse, &charMapper, fFilterZeroWidth, glyphStorage);
480 }
481 
482 // Input: characters, font?
483 // Output: glyphs, positions, char indices
484 // Returns: number of glyphs
layoutChars(const LEUnicode chars[],le_int32 offset,le_int32 count,le_int32 max,le_bool rightToLeft,float x,float y,LEErrorCode & success)485 le_int32 LayoutEngine::layoutChars(const LEUnicode chars[], le_int32 offset, le_int32 count, le_int32 max, le_bool rightToLeft,
486                               float x, float y, LEErrorCode &success)
487 {
488     if (LE_FAILURE(success)) {
489         return 0;
490     }
491 
492     if (chars == NULL || offset < 0 || count < 0 || max < 0 || offset >= max || offset + count > max) {
493         success = LE_ILLEGAL_ARGUMENT_ERROR;
494         return 0;
495     }
496 
497     le_int32 glyphCount;
498 
499     if (fGlyphStorage->getGlyphCount() > 0) {
500         fGlyphStorage->reset();
501     }
502 
503     glyphCount = computeGlyphs(chars, offset, count, max, rightToLeft, *fGlyphStorage, success);
504     positionGlyphs(*fGlyphStorage, x, y, success);
505     adjustGlyphPositions(chars, offset, count, rightToLeft, *fGlyphStorage, success);
506 
507     return glyphCount;
508 }
509 
reset()510 void LayoutEngine::reset()
511 {
512     fGlyphStorage->reset();
513 }
514 
layoutEngineFactory(const LEFontInstance * fontInstance,le_int32 scriptCode,le_int32 languageCode,LEErrorCode & success)515 LayoutEngine *LayoutEngine::layoutEngineFactory(const LEFontInstance *fontInstance, le_int32 scriptCode, le_int32 languageCode, LEErrorCode &success)
516 {
517   // 3 -> kerning and ligatures
518   return LayoutEngine::layoutEngineFactory(fontInstance, scriptCode, languageCode, 3, success);
519 }
520 
layoutEngineFactory(const LEFontInstance * fontInstance,le_int32 scriptCode,le_int32 languageCode,le_int32 typoFlags,LEErrorCode & success)521 LayoutEngine *LayoutEngine::layoutEngineFactory(const LEFontInstance *fontInstance, le_int32 scriptCode, le_int32 languageCode, le_int32 typoFlags, LEErrorCode &success)
522 {
523     static const le_uint32 gsubTableTag = LE_GSUB_TABLE_TAG;
524     static const le_uint32 mortTableTag = LE_MORT_TABLE_TAG;
525     static const le_uint32 morxTableTag = LE_MORX_TABLE_TAG;
526 
527     if (LE_FAILURE(success)) {
528         return NULL;
529     }
530 
531     const GlyphSubstitutionTableHeader *gsubTable = (const GlyphSubstitutionTableHeader *) fontInstance->getFontTable(gsubTableTag);
532     LayoutEngine *result = NULL;
533     LETag scriptTag   = 0x00000000;
534     LETag languageTag = 0x00000000;
535 	LETag v2ScriptTag = OpenTypeLayoutEngine::getV2ScriptTag(scriptCode);
536 
537     // Right now, only invoke V2 processing for Devanagari.  TODO: Allow more V2 scripts as they are
538     // properly tested.
539 
540 	if ( v2ScriptTag == dev2ScriptTag && gsubTable != NULL && gsubTable->coversScript( v2ScriptTag )) {
541 		result = new IndicOpenTypeLayoutEngine(fontInstance, scriptCode, languageCode, typoFlags, TRUE, gsubTable, success);
542 	}
543     else if (gsubTable != NULL && gsubTable->coversScript(scriptTag = OpenTypeLayoutEngine::getScriptTag(scriptCode))) {
544         switch (scriptCode) {
545         case bengScriptCode:
546         case devaScriptCode:
547         case gujrScriptCode:
548         case kndaScriptCode:
549         case mlymScriptCode:
550         case oryaScriptCode:
551         case guruScriptCode:
552         case tamlScriptCode:
553         case teluScriptCode:
554         case sinhScriptCode:
555             result = new IndicOpenTypeLayoutEngine(fontInstance, scriptCode, languageCode, typoFlags, FALSE, gsubTable, success);
556             break;
557 
558         case arabScriptCode:
559             result = new ArabicOpenTypeLayoutEngine(fontInstance, scriptCode, languageCode, typoFlags, gsubTable, success);
560             break;
561 
562         case hebrScriptCode:
563             // Disable hebrew ligatures since they have only archaic uses, see ticket #8318
564             result = new OpenTypeLayoutEngine(fontInstance, scriptCode, languageCode, typoFlags & ~kTypoFlagLiga, gsubTable, success);
565             break;
566 
567         case hangScriptCode:
568             result = new HangulOpenTypeLayoutEngine(fontInstance, scriptCode, languageCode, typoFlags, gsubTable, success);
569             break;
570 
571         case haniScriptCode:
572             languageTag = OpenTypeLayoutEngine::getLangSysTag(languageCode);
573 
574             switch (languageCode) {
575             case korLanguageCode:
576             case janLanguageCode:
577             case zhtLanguageCode:
578             case zhsLanguageCode:
579                 if (gsubTable->coversScriptAndLanguage(scriptTag, languageTag, TRUE)) {
580                     result = new HanOpenTypeLayoutEngine(fontInstance, scriptCode, languageCode, typoFlags, gsubTable, success);
581                     break;
582                 }
583 
584                 // note: falling through to default case.
585             default:
586                 result = new OpenTypeLayoutEngine(fontInstance, scriptCode, languageCode, typoFlags, gsubTable, success);
587                 break;
588             }
589 
590             break;
591 
592         case tibtScriptCode:
593             result = new TibetanOpenTypeLayoutEngine(fontInstance, scriptCode, languageCode, typoFlags, gsubTable, success);
594             break;
595 
596         case khmrScriptCode:
597             result = new KhmerOpenTypeLayoutEngine(fontInstance, scriptCode, languageCode, typoFlags, gsubTable, success);
598             break;
599 
600         default:
601             result = new OpenTypeLayoutEngine(fontInstance, scriptCode, languageCode, typoFlags, gsubTable, success);
602             break;
603         }
604     } else {
605         MorphTableHeader2 *morxTable = (MorphTableHeader2 *)fontInstance->getFontTable(morxTableTag);
606         if (morxTable != NULL) {
607             result = new GXLayoutEngine2(fontInstance, scriptCode, languageCode, morxTable, typoFlags, success);
608         } else {
609             const MorphTableHeader *mortTable = (MorphTableHeader *) fontInstance->getFontTable(mortTableTag);
610             if (mortTable != NULL) { // mort
611                 result = new GXLayoutEngine(fontInstance, scriptCode, languageCode, mortTable, success);
612             } else {
613                 switch (scriptCode) {
614                     case bengScriptCode:
615                     case devaScriptCode:
616                     case gujrScriptCode:
617                     case kndaScriptCode:
618                     case mlymScriptCode:
619                     case oryaScriptCode:
620                     case guruScriptCode:
621                     case tamlScriptCode:
622                     case teluScriptCode:
623                     case sinhScriptCode:
624                     {
625                         result = new IndicOpenTypeLayoutEngine(fontInstance, scriptCode, languageCode, typoFlags, success);
626                         break;
627                     }
628 
629                     case arabScriptCode:
630                         //case hebrScriptCode:
631                         result = new UnicodeArabicOpenTypeLayoutEngine(fontInstance, scriptCode, languageCode, typoFlags, success);
632                         break;
633 
634                         //case hebrScriptCode:
635                         //    return new HebrewOpenTypeLayoutEngine(fontInstance, scriptCode, languageCode, typoFlags);
636 
637                     case thaiScriptCode:
638                         result = new ThaiLayoutEngine(fontInstance, scriptCode, languageCode, typoFlags, success);
639                         break;
640 
641                     case hangScriptCode:
642                         result = new HangulOpenTypeLayoutEngine(fontInstance, scriptCode, languageCode, typoFlags, success);
643                         break;
644 
645                     default:
646                         result = new LayoutEngine(fontInstance, scriptCode, languageCode, typoFlags, success);
647                         break;
648                 }
649             }
650         }
651     }
652 
653     if (result && LE_FAILURE(success)) {
654 		delete result;
655 		result = NULL;
656 	}
657 
658     if (result == NULL) {
659         success = LE_MEMORY_ALLOCATION_ERROR;
660     }
661 
662     return result;
663 }
664 
~LayoutEngine()665 LayoutEngine::~LayoutEngine() {
666     delete fGlyphStorage;
667 }
668 
669 U_NAMESPACE_END
670