1 /*
2 * Copyright 2016 Google Inc.
3 *
4 * Use of this source code is governed by a BSD-style license that can be
5 * found in the LICENSE file.
6 */
7
8 #include "include/core/SkFont.h"
9 #include "include/core/SkFontArguments.h"
10 #include "include/core/SkFontMetrics.h"
11 #include "include/core/SkFontMgr.h"
12 #include "include/core/SkFontTypes.h"
13 #include "include/core/SkPaint.h"
14 #include "include/core/SkPoint.h"
15 #include "include/core/SkRect.h"
16 #include "include/core/SkRefCnt.h"
17 #include "include/core/SkScalar.h"
18 #include "include/core/SkSpan.h"
19 #include "include/core/SkStream.h"
20 #include "include/core/SkTypeface.h"
21 #include "include/core/SkTypes.h"
22 #include "include/private/SkBitmaskEnum.h"
23 #include "include/private/SkMalloc.h"
24 #include "include/private/SkMutex.h"
25 #include "include/private/SkTArray.h"
26 #include "include/private/SkTFitsIn.h"
27 #include "include/private/SkTo.h"
28 #include "modules/skshaper/include/SkShaper.h"
29 #include "modules/skunicode/include/SkUnicode.h"
30 #include "src/core/SkTDPQueue.h"
31 #include "src/utils/SkUTF.h"
32 #include "src/core/SkLRUCache.h"
33
34 #include <hb.h>
35 #include <hb-ot.h>
36 #include <cstring>
37 #include <locale>
38 #include <memory>
39 #include <type_traits>
40 #include <utility>
41
42
43 // HB_FEATURE_GLOBAL_START and HB_FEATURE_GLOBAL_END were not added until HarfBuzz 2.0
44 // They would have always worked, they just hadn't been named yet.
45 #if !defined(HB_FEATURE_GLOBAL_START)
46 # define HB_FEATURE_GLOBAL_START 0
47 #endif
48 #if !defined(HB_FEATURE_GLOBAL_END)
49 # define HB_FEATURE_GLOBAL_END ((unsigned int) -1)
50 #endif
51
52 namespace sknonstd {
53 template <> struct is_bitmask_enum<hb_buffer_flags_t> : std::true_type {};
54 } // namespace sknonstd
55
56 namespace {
57 template <typename T,typename P,P* p> using resource = std::unique_ptr<T, SkFunctionWrapper<P, p>>;
58 using HBBlob = resource<hb_blob_t , decltype(hb_blob_destroy) , hb_blob_destroy >;
59 using HBFace = resource<hb_face_t , decltype(hb_face_destroy) , hb_face_destroy >;
60 using HBFont = resource<hb_font_t , decltype(hb_font_destroy) , hb_font_destroy >;
61 using HBBuffer = resource<hb_buffer_t , decltype(hb_buffer_destroy), hb_buffer_destroy>;
62
63 using SkUnicodeBidi = std::unique_ptr<SkBidiIterator>;
64 using SkUnicodeBreak = std::unique_ptr<SkBreakIterator>;
65
skhb_position(SkScalar value)66 hb_position_t skhb_position(SkScalar value) {
67 // Treat HarfBuzz hb_position_t as 16.16 fixed-point.
68 constexpr int kHbPosition1 = 1 << 16;
69 return SkScalarRoundToInt(value * kHbPosition1);
70 }
71
skhb_glyph(hb_font_t * hb_font,void * font_data,hb_codepoint_t unicode,hb_codepoint_t variation_selector,hb_codepoint_t * glyph,void * user_data)72 hb_bool_t skhb_glyph(hb_font_t* hb_font,
73 void* font_data,
74 hb_codepoint_t unicode,
75 hb_codepoint_t variation_selector,
76 hb_codepoint_t* glyph,
77 void* user_data) {
78 #ifndef USE_SKIA_TXT
79 SkFont& font = *reinterpret_cast<SkFont*>(font_data);
80
81 *glyph = font.unicharToGlyph(unicode);
82 #else
83 RSFont& font = *reinterpret_cast<RSFont*>(font_data);
84
85 *glyph = font.UnicharToGlyph(unicode);
86 #endif
87 return *glyph != 0;
88 }
89
skhb_nominal_glyph(hb_font_t * hb_font,void * font_data,hb_codepoint_t unicode,hb_codepoint_t * glyph,void * user_data)90 hb_bool_t skhb_nominal_glyph(hb_font_t* hb_font,
91 void* font_data,
92 hb_codepoint_t unicode,
93 hb_codepoint_t* glyph,
94 void* user_data) {
95 return skhb_glyph(hb_font, font_data, unicode, 0, glyph, user_data);
96 }
97
skhb_nominal_glyphs(hb_font_t * hb_font,void * font_data,unsigned int count,const hb_codepoint_t * unicodes,unsigned int unicode_stride,hb_codepoint_t * glyphs,unsigned int glyph_stride,void * user_data)98 unsigned skhb_nominal_glyphs(hb_font_t *hb_font, void *font_data,
99 unsigned int count,
100 const hb_codepoint_t *unicodes,
101 unsigned int unicode_stride,
102 hb_codepoint_t *glyphs,
103 unsigned int glyph_stride,
104 void *user_data) {
105 #ifndef USE_SKIA_TXT
106 SkFont& font = *reinterpret_cast<SkFont*>(font_data);
107 #else
108 RSFont& font = *reinterpret_cast<RSFont*>(font_data);
109 #endif
110
111 // Batch call textToGlyphs since entry cost is not cheap.
112 // Copy requred because textToGlyphs is dense and hb is strided.
113 SkAutoSTMalloc<256, SkUnichar> unicode(count);
114 for (unsigned i = 0; i < count; i++) {
115 unicode[i] = *unicodes;
116 unicodes = SkTAddOffset<const hb_codepoint_t>(unicodes, unicode_stride);
117 }
118 SkAutoSTMalloc<256, SkGlyphID> glyph(count);
119 #ifndef USE_SKIA_TXT
120 font.textToGlyphs(unicode.get(), count * sizeof(SkUnichar), SkTextEncoding::kUTF32,
121 glyph.get(), count);
122 #else
123 font.TextToGlyphs(unicode.get(), count * sizeof(SkUnichar), RSDrawing::TextEncoding::UTF32,
124 glyph.get(), count);
125 #endif
126
127 // Copy the results back to the sparse array.
128 unsigned int done;
129 for (done = 0; done < count && glyph[done] != 0; done++) {
130 *glyphs = glyph[done];
131 glyphs = SkTAddOffset<hb_codepoint_t>(glyphs, glyph_stride);
132 }
133 // return 'done' to allow HarfBuzz to synthesize with NFC and spaces, return 'count' to avoid
134 return done;
135 }
136
skhb_glyph_h_advance(hb_font_t * hb_font,void * font_data,hb_codepoint_t hbGlyph,void * user_data)137 hb_position_t skhb_glyph_h_advance(hb_font_t* hb_font,
138 void* font_data,
139 hb_codepoint_t hbGlyph,
140 void* user_data) {
141 #ifndef USE_SKIA_TXT
142 SkFont& font = *reinterpret_cast<SkFont*>(font_data);
143 #else
144 RSFont& font = *reinterpret_cast<RSFont*>(font_data);
145 #endif
146
147 SkScalar advance;
148 SkGlyphID skGlyph = SkTo<SkGlyphID>(hbGlyph);
149
150 #ifndef USE_SKIA_TXT
151 font.getWidths(&skGlyph, 1, &advance);
152 if (!font.isSubpixel()) {
153 advance = SkScalarRoundToInt(advance);
154 }
155 #else
156 font.GetWidths(&skGlyph, 1, &advance);
157 if (!font.IsSubpixel()) {
158 advance = SkScalarRoundToInt(advance);
159 }
160 #endif
161 return skhb_position(advance);
162 }
163
skhb_glyph_h_advances(hb_font_t * hb_font,void * font_data,unsigned count,const hb_codepoint_t * glyphs,unsigned int glyph_stride,hb_position_t * advances,unsigned int advance_stride,void * user_data)164 void skhb_glyph_h_advances(hb_font_t* hb_font,
165 void* font_data,
166 unsigned count,
167 const hb_codepoint_t* glyphs,
168 unsigned int glyph_stride,
169 hb_position_t* advances,
170 unsigned int advance_stride,
171 void* user_data) {
172 #ifndef USE_SKIA_TXT
173 SkFont& font = *reinterpret_cast<SkFont*>(font_data);
174 #else
175 RSFont& font = *reinterpret_cast<RSFont*>(font_data);
176 #endif
177
178 // Batch call getWidths since entry cost is not cheap.
179 // Copy requred because getWidths is dense and hb is strided.
180 SkAutoSTMalloc<256, SkGlyphID> glyph(count);
181 for (unsigned i = 0; i < count; i++) {
182 glyph[i] = *glyphs;
183 glyphs = SkTAddOffset<const hb_codepoint_t>(glyphs, glyph_stride);
184 }
185 SkAutoSTMalloc<256, SkScalar> advance(count);
186 #ifndef USE_SKIA_TXT
187 font.getWidths(glyph.get(), count, advance.get());
188 #else
189 font.GetWidths(glyph.get(), count, advance.get());
190 #endif
191
192 #ifndef USE_SKIA_TXT
193 if (!font.isSubpixel()) {
194 #else
195 if (!font.IsSubpixel()) {
196 #endif
197 for (unsigned i = 0; i < count; i++) {
198 advance[i] = SkScalarRoundToInt(advance[i]);
199 }
200 }
201
202 // Copy the results back to the sparse array.
203 for (unsigned i = 0; i < count; i++) {
204 *advances = skhb_position(advance[i]);
205 advances = SkTAddOffset<hb_position_t>(advances, advance_stride);
206 }
207 }
208
209 // HarfBuzz callback to retrieve glyph extents, mainly used by HarfBuzz for
210 // fallback mark positioning, i.e. the situation when the font does not have
211 // mark anchors or other mark positioning rules, but instead HarfBuzz is
212 // supposed to heuristically place combining marks around base glyphs. HarfBuzz
213 // does this by measuring "ink boxes" of glyphs, and placing them according to
214 // Unicode mark classes. Above, below, centered or left or right, etc.
215 hb_bool_t skhb_glyph_extents(hb_font_t* hb_font,
216 void* font_data,
217 hb_codepoint_t hbGlyph,
218 hb_glyph_extents_t* extents,
219 void* user_data) {
220 #ifndef USE_SKIA_TXT
221 SkFont& font = *reinterpret_cast<SkFont*>(font_data);
222 #else
223 RSFont& font = *reinterpret_cast<RSFont*>(font_data);
224 #endif
225 SkASSERT(extents);
226
227 #ifndef USE_SKIA_TXT
228 SkRect sk_bounds;
229 SkGlyphID skGlyph = SkTo<SkGlyphID>(hbGlyph);
230
231 font.getWidths(&skGlyph, 1, nullptr, &sk_bounds);
232 if (!font.isSubpixel()) {
233 sk_bounds.set(sk_bounds.roundOut());
234 }
235
236 // Skia is y-down but HarfBuzz is y-up.
237 extents->x_bearing = skhb_position(sk_bounds.fLeft);
238 extents->y_bearing = skhb_position(-sk_bounds.fTop);
239 extents->width = skhb_position(sk_bounds.width());
240 extents->height = skhb_position(-sk_bounds.height());
241 #else
242 RSRect bounds;
243 SkGlyphID skGlyph = SkTo<SkGlyphID>(hbGlyph);
244
245 font.GetWidths(&skGlyph, 1, nullptr, &bounds);
246 if (!font.IsSubpixel()) {
247 bounds = RSRect(bounds.RoundOut());
248 }
249
250 // Skia is y-down but HarfBuzz is y-up.
251 extents->x_bearing = skhb_position(bounds.left_);
252 extents->y_bearing = skhb_position(-bounds.top_);
253 extents->width = skhb_position(bounds.GetWidth());
254 extents->height = skhb_position(-bounds.GetHeight());
255 #endif
256 return true;
257 }
258
259 #define SK_HB_VERSION_CHECK(x, y, z) \
260 (HB_VERSION_MAJOR > (x)) || \
261 (HB_VERSION_MAJOR == (x) && HB_VERSION_MINOR > (y)) || \
262 (HB_VERSION_MAJOR == (x) && HB_VERSION_MINOR == (y) && HB_VERSION_MICRO >= (z))
263
264 hb_font_funcs_t* skhb_get_font_funcs() {
265 static hb_font_funcs_t* const funcs = []{
266 // HarfBuzz will use the default (parent) implementation if they aren't set.
267 hb_font_funcs_t* const funcs = hb_font_funcs_create();
268 hb_font_funcs_set_variation_glyph_func(funcs, skhb_glyph, nullptr, nullptr);
269 hb_font_funcs_set_nominal_glyph_func(funcs, skhb_nominal_glyph, nullptr, nullptr);
270 #if SK_HB_VERSION_CHECK(2, 0, 0)
271 hb_font_funcs_set_nominal_glyphs_func(funcs, skhb_nominal_glyphs, nullptr, nullptr);
272 #else
273 sk_ignore_unused_variable(skhb_nominal_glyphs);
274 #endif
275 hb_font_funcs_set_glyph_h_advance_func(funcs, skhb_glyph_h_advance, nullptr, nullptr);
276 #if SK_HB_VERSION_CHECK(1, 8, 6)
277 hb_font_funcs_set_glyph_h_advances_func(funcs, skhb_glyph_h_advances, nullptr, nullptr);
278 #else
279 sk_ignore_unused_variable(skhb_glyph_h_advances);
280 #endif
281 hb_font_funcs_set_glyph_extents_func(funcs, skhb_glyph_extents, nullptr, nullptr);
282 hb_font_funcs_make_immutable(funcs);
283 return funcs;
284 }();
285 SkASSERT(funcs);
286 return funcs;
287 }
288
289 hb_blob_t* skhb_get_table(hb_face_t* face, hb_tag_t tag, void* user_data) {
290 #ifndef USE_SKIA_TXT
291 SkTypeface& typeface = *reinterpret_cast<SkTypeface*>(user_data);
292
293 auto data = typeface.copyTableData(tag);
294 if (!data) {
295 return nullptr;
296 }
297 SkData* rawData = data.release();
298 return hb_blob_create(reinterpret_cast<char*>(rawData->writable_data()), rawData->size(),
299 HB_MEMORY_MODE_READONLY, rawData, [](void* ctx) {
300 SkSafeUnref(((SkData*)ctx));
301 });
302 #else
303 RSTypeface& typeface = *reinterpret_cast<RSTypeface*>(user_data);
304
305 auto size = typeface.GetTableSize(tag);
306 if (!size) {
307 return nullptr;
308 }
309 auto data = std::make_unique<char[]>(size);
310 if (!data) {
311 return nullptr;
312 }
313 auto relTableSize = typeface.GetTableData(tag, 0, size, data.get());
314 if (relTableSize != size) {
315 return nullptr;
316 }
317
318 auto rawData = data.release();
319 return hb_blob_create(rawData, size,
320 HB_MEMORY_MODE_READONLY, rawData, [](void* ctx) {
321 std::unique_ptr<char[]>((char*)ctx);
322 });
323 #endif
324 }
325
326 #ifndef USE_SKIA_TXT
327 HBBlob stream_to_blob(std::unique_ptr<SkStreamAsset> asset) {
328 size_t size = asset->getLength();
329 HBBlob blob;
330 if (const void* base = asset->getMemoryBase()) {
331 blob.reset(hb_blob_create((char*)base, SkToUInt(size),
332 HB_MEMORY_MODE_READONLY, asset.release(),
333 [](void* p) { delete (SkStreamAsset*)p; }));
334 } else {
335 // SkDebugf("Extra SkStreamAsset copy\n");
336 void* ptr = size ? sk_malloc_throw(size) : nullptr;
337 asset->read(ptr, size);
338 blob.reset(hb_blob_create((char*)ptr, SkToUInt(size),
339 HB_MEMORY_MODE_READONLY, ptr, sk_free));
340 }
341 SkASSERT(blob);
342 hb_blob_make_immutable(blob.get());
343 return blob;
344 }
345
346 SkDEBUGCODE(static hb_user_data_key_t gDataIdKey;)
347
348 HBFace create_hb_face(const SkTypeface& typeface) {
349 int index = 0;
350 std::unique_ptr<SkStreamAsset> typefaceAsset = typeface.openExistingStream(&index);
351 HBFace face;
352 if (typefaceAsset && typefaceAsset->getMemoryBase()) {
353 HBBlob blob(stream_to_blob(std::move(typefaceAsset)));
354 // hb_face_create always succeeds. Check that the format is minimally recognized first.
355 // hb_face_create_for_tables may still create a working hb_face.
356 // See https://github.com/harfbuzz/harfbuzz/issues/248 .
357 unsigned int num_hb_faces = hb_face_count(blob.get());
358 if (0 < num_hb_faces && (unsigned)index < num_hb_faces) {
359 face.reset(hb_face_create(blob.get(), (unsigned)index));
360 // Check the number of glyphs as a basic sanitization step.
361 if (face && hb_face_get_glyph_count(face.get()) == 0) {
362 face.reset();
363 }
364 }
365 }
366 if (!face) {
367 face.reset(hb_face_create_for_tables(
368 skhb_get_table,
369 const_cast<SkTypeface*>(SkRef(&typeface)),
370 [](void* user_data){ SkSafeUnref(reinterpret_cast<SkTypeface*>(user_data)); }));
371 hb_face_set_index(face.get(), (unsigned)index);
372 }
373 SkASSERT(face);
374 if (!face) {
375 return nullptr;
376 }
377 hb_face_set_upem(face.get(), typeface.getUnitsPerEm());
378
379 SkDEBUGCODE(
380 hb_face_set_user_data(face.get(), &gDataIdKey, const_cast<SkTypeface*>(&typeface),
381 nullptr, false);
382 )
383
384 return face;
385 }
386 #else
387 HBFace create_hb_face(const RSTypeface& typeface) {
388 int index = 0;
389 HBFace face;
390 if (!face) {
391 face.reset(hb_face_create_for_tables(
392 skhb_get_table,
393 const_cast<RSTypeface*>(std::make_unique<RSTypeface>(typeface).release()),
394 [](void* user_data){ std::unique_ptr<RSTypeface>(reinterpret_cast<RSTypeface*>(user_data)); }));
395 hb_face_set_index(face.get(), (unsigned)index);
396 }
397 SkASSERT(face);
398 if (!face) {
399 return nullptr;
400 }
401 hb_face_set_upem(face.get(), typeface.GetUnitsPerEm());
402
403 return face;
404 }
405 #endif
406
407 #ifndef USE_SKIA_TXT
408 HBFont create_typeface_hb_font(const SkTypeface& typeface) {
409 #else
410 HBFont create_typeface_hb_font(const RSTypeface& typeface) {
411 #endif
412 HBFace face(create_hb_face(typeface));
413 if (!face) {
414 return nullptr;
415 }
416
417 HBFont otFont(hb_font_create(face.get()));
418 SkASSERT(otFont);
419 if (!otFont) {
420 return nullptr;
421 }
422 hb_ot_font_set_funcs(otFont.get());
423 #ifndef USE_SKIA_TXT
424 int axis_count = typeface.getVariationDesignPosition(nullptr, 0);
425 if (axis_count > 0) {
426 SkAutoSTMalloc<4, SkFontArguments::VariationPosition::Coordinate> axis_values(axis_count);
427 if (typeface.getVariationDesignPosition(axis_values, axis_count) == axis_count) {
428 hb_font_set_variations(otFont.get(),
429 reinterpret_cast<hb_variation_t*>(axis_values.get()),
430 axis_count);
431 }
432 }
433 #endif
434
435 return otFont;
436 }
437
438 #ifndef USE_SKIA_TXT
439 HBFont create_sub_hb_font(const SkFont& font, const HBFont& typefaceFont) {
440 SkDEBUGCODE(
441 hb_face_t* face = hb_font_get_face(typefaceFont.get());
442 void* dataId = hb_face_get_user_data(face, &gDataIdKey);
443 SkASSERT(dataId == font.getTypeface());
444 )
445
446 // Creating a sub font means that non-available functions
447 // are found from the parent.
448 HBFont skFont(hb_font_create_sub_font(typefaceFont.get()));
449 hb_font_set_funcs(skFont.get(), skhb_get_font_funcs(),
450 reinterpret_cast<void *>(new SkFont(font)),
451 [](void* user_data){ delete reinterpret_cast<SkFont*>(user_data); });
452 int scale = skhb_position(font.getSize());
453 hb_font_set_scale(skFont.get(), scale, scale);
454
455 return skFont;
456 }
457 #else
458 HBFont create_sub_hb_font(const RSFont& font, const HBFont& typefaceFont) {
459 // Creating a sub font means that non-available functions
460 // are found from the parent.
461 HBFont skFont(hb_font_create_sub_font(typefaceFont.get()));
462 hb_font_set_funcs(skFont.get(), skhb_get_font_funcs(),
463 reinterpret_cast<void *>(std::make_unique<RSFont>(font).release()),
464 [](void* user_data){ std::unique_ptr<RSFont>(reinterpret_cast<RSFont*>(user_data)); });
465 int scale = skhb_position(font.GetSize());
466 hb_font_set_scale(skFont.get(), scale, scale);
467
468 return skFont;
469 }
470 #endif
471
472 /** Replaces invalid utf-8 sequences with REPLACEMENT CHARACTER U+FFFD. */
473 static inline SkUnichar utf8_next(const char** ptr, const char* end) {
474 SkUnichar val = SkUTF::NextUTF8(ptr, end);
475 return val < 0 ? 0xFFFD : val;
476 }
477
478 class SkUnicodeBidiRunIterator final : public SkShaper::BiDiRunIterator {
479 public:
480 SkUnicodeBidiRunIterator(const char* utf8, const char* end, SkUnicodeBidi bidi)
481 : fBidi(std::move(bidi))
482 , fEndOfCurrentRun(utf8)
483 , fBegin(utf8)
484 , fEnd(end)
485 , fUTF16LogicalPosition(0)
486 , fLevel(SkBidiIterator::kLTR)
487 {}
488
489 void consume() override {
490 SkASSERT(fUTF16LogicalPosition < fBidi->getLength());
491 int32_t endPosition = fBidi->getLength();
492 fLevel = fBidi->getLevelAt(fUTF16LogicalPosition);
493 SkUnichar u = utf8_next(&fEndOfCurrentRun, fEnd);
494 fUTF16LogicalPosition += SkUTF::ToUTF16(u);
495 SkBidiIterator::Level level;
496 while (fUTF16LogicalPosition < endPosition) {
497 level = fBidi->getLevelAt(fUTF16LogicalPosition);
498 if (level != fLevel) {
499 break;
500 }
501 u = utf8_next(&fEndOfCurrentRun, fEnd);
502
503 fUTF16LogicalPosition += SkUTF::ToUTF16(u);
504 }
505 }
506 size_t endOfCurrentRun() const override {
507 return fEndOfCurrentRun - fBegin;
508 }
509 bool atEnd() const override {
510 return fUTF16LogicalPosition == fBidi->getLength();
511 }
512 SkBidiIterator::Level currentLevel() const override {
513 return fLevel;
514 }
515 private:
516 SkUnicodeBidi fBidi;
517 char const * fEndOfCurrentRun;
518 char const * const fBegin;
519 char const * const fEnd;
520 int32_t fUTF16LogicalPosition;
521 SkBidiIterator::Level fLevel;
522 };
523
524 class SkUnicodeHbScriptRunIterator final: public SkShaper::ScriptRunIterator {
525 public:
526 SkUnicodeHbScriptRunIterator(const char* utf8,
527 size_t utf8Bytes,
528 hb_script_t defaultScript)
529 : fCurrent(utf8)
530 , fBegin(utf8)
531 , fEnd(fCurrent + utf8Bytes)
532 , fCurrentScript(defaultScript) {}
533 hb_script_t hb_script_for_unichar(SkUnichar u) {
534 return hb_unicode_script(hb_unicode_funcs_get_default(), u);
535 }
536 void consume() override {
537 SkASSERT(fCurrent < fEnd);
538 SkUnichar u = utf8_next(&fCurrent, fEnd);
539 fCurrentScript = hb_script_for_unichar(u);
540 while (fCurrent < fEnd) {
541 const char* prev = fCurrent;
542 u = utf8_next(&fCurrent, fEnd);
543 const hb_script_t script = hb_script_for_unichar(u);
544 if (script != fCurrentScript) {
545 if (fCurrentScript == HB_SCRIPT_INHERITED || fCurrentScript == HB_SCRIPT_COMMON) {
546 fCurrentScript = script;
547 } else if (script == HB_SCRIPT_INHERITED || script == HB_SCRIPT_COMMON) {
548 continue;
549 } else {
550 fCurrent = prev;
551 break;
552 }
553 }
554 }
555 if (fCurrentScript == HB_SCRIPT_INHERITED) {
556 fCurrentScript = HB_SCRIPT_COMMON;
557 }
558 }
559 size_t endOfCurrentRun() const override {
560 return fCurrent - fBegin;
561 }
562 bool atEnd() const override {
563 return fCurrent == fEnd;
564 }
565
566 SkFourByteTag currentScript() const override {
567 return SkSetFourByteTag(HB_UNTAG(fCurrentScript));
568 }
569 private:
570 char const * fCurrent;
571 char const * const fBegin;
572 char const * const fEnd;
573 hb_script_t fCurrentScript;
574 };
575
576 class RunIteratorQueue {
577 public:
578 void insert(SkShaper::RunIterator* runIterator, int priority) {
579 fEntries.insert({runIterator, priority});
580 }
581
582 bool advanceRuns() {
583 const SkShaper::RunIterator* leastRun = fEntries.peek().runIterator;
584 if (leastRun->atEnd()) {
585 SkASSERT(this->allRunsAreAtEnd());
586 return false;
587 }
588 const size_t leastEnd = leastRun->endOfCurrentRun();
589 SkShaper::RunIterator* currentRun = nullptr;
590 SkDEBUGCODE(size_t previousEndOfCurrentRun);
591 while ((currentRun = fEntries.peek().runIterator)->endOfCurrentRun() <= leastEnd) {
592 int priority = fEntries.peek().priority;
593 fEntries.pop();
594 SkDEBUGCODE(previousEndOfCurrentRun = currentRun->endOfCurrentRun());
595 currentRun->consume();
596 SkASSERT(previousEndOfCurrentRun < currentRun->endOfCurrentRun());
597 fEntries.insert({currentRun, priority});
598 }
599 return true;
600 }
601
602 size_t endOfCurrentRun() const {
603 return fEntries.peek().runIterator->endOfCurrentRun();
604 }
605
606 private:
607 bool allRunsAreAtEnd() const {
608 for (int i = 0; i < fEntries.count(); ++i) {
609 if (!fEntries.at(i).runIterator->atEnd()) {
610 return false;
611 }
612 }
613 return true;
614 }
615
616 struct Entry {
617 SkShaper::RunIterator* runIterator;
618 int priority;
619 };
620 static bool CompareEntry(Entry const& a, Entry const& b) {
621 size_t aEnd = a.runIterator->endOfCurrentRun();
622 size_t bEnd = b.runIterator->endOfCurrentRun();
623 return aEnd < bEnd || (aEnd == bEnd && a.priority < b.priority);
624 }
625 SkTDPQueue<Entry, CompareEntry> fEntries;
626 };
627
628 struct ShapedGlyph {
629 SkGlyphID fID;
630 uint32_t fCluster;
631 SkPoint fOffset;
632 SkVector fAdvance;
633 bool fMayLineBreakBefore;
634 bool fMustLineBreakBefore;
635 bool fHasVisual;
636 bool fGraphemeBreakBefore;
637 bool fUnsafeToBreak;
638 };
639 #ifndef USE_SKIA_TXT
640 struct ShapedRun {
641 ShapedRun(SkShaper::RunHandler::Range utf8Range, const SkFont& font, SkBidiIterator::Level level,
642 std::unique_ptr<ShapedGlyph[]> glyphs, size_t numGlyphs, SkVector advance = {0, 0})
643 : fUtf8Range(utf8Range), fFont(font), fLevel(level)
644 , fGlyphs(std::move(glyphs)), fNumGlyphs(numGlyphs), fAdvance(advance)
645 {}
646
647 SkShaper::RunHandler::Range fUtf8Range;
648 SkFont fFont;
649 SkBidiIterator::Level fLevel;
650 std::unique_ptr<ShapedGlyph[]> fGlyphs;
651 size_t fNumGlyphs;
652 SkVector fAdvance;
653 };
654 #else
655 struct ShapedRun {
656 ShapedRun(SkShaper::RunHandler::Range utf8Range, const RSFont& font, SkBidiIterator::Level level,
657 std::unique_ptr<ShapedGlyph[]> glyphs, size_t numGlyphs, SkVector advance = {0, 0})
658 : fUtf8Range(utf8Range), fFont(font), fLevel(level),
659 fGlyphs(std::move(glyphs)), fNumGlyphs(numGlyphs), fAdvance(advance)
660 {}
661
662 SkShaper::RunHandler::Range fUtf8Range;
663 RSFont fFont;
664 SkBidiIterator::Level fLevel;
665 std::unique_ptr<ShapedGlyph[]> fGlyphs;
666 size_t fNumGlyphs;
667 SkVector fAdvance;
668 };
669 #endif
670 struct ShapedLine {
671 SkTArray<ShapedRun> runs;
672 SkVector fAdvance = { 0, 0 };
673 };
674
675 constexpr bool is_LTR(SkBidiIterator::Level level) {
676 return (level & 1) == 0;
677 }
678
679 void append(SkShaper::RunHandler* handler, const SkShaper::RunHandler::RunInfo& runInfo,
680 const ShapedRun& run, size_t startGlyphIndex, size_t endGlyphIndex) {
681 SkASSERT(startGlyphIndex <= endGlyphIndex);
682 const size_t glyphLen = endGlyphIndex - startGlyphIndex;
683
684 const auto buffer = handler->runBuffer(runInfo);
685 SkASSERT(buffer.glyphs);
686 SkASSERT(buffer.positions);
687
688 SkVector advance = {0,0};
689 for (size_t i = 0; i < glyphLen; i++) {
690 // Glyphs are in logical order, but output ltr since PDF readers seem to expect that.
691 const ShapedGlyph& glyph = run.fGlyphs[is_LTR(run.fLevel) ? startGlyphIndex + i
692 : endGlyphIndex - 1 - i];
693 buffer.glyphs[i] = glyph.fID;
694 if (buffer.offsets) {
695 buffer.positions[i] = advance + buffer.point;
696 buffer.offsets[i] = glyph.fOffset;
697 } else {
698 buffer.positions[i] = advance + buffer.point + glyph.fOffset;
699 }
700 if (buffer.clusters) {
701 buffer.clusters[i] = glyph.fCluster;
702 }
703 advance += glyph.fAdvance;
704 }
705 handler->commitRunBuffer(runInfo);
706 }
707
708 void emit(SkUnicode* unicode, const ShapedLine& line, SkShaper::RunHandler* handler) {
709 // Reorder the runs and glyphs per line and write them out.
710 handler->beginLine();
711
712 int numRuns = line.runs.size();
713 SkAutoSTMalloc<4, SkBidiIterator::Level> runLevels(numRuns);
714 for (int i = 0; i < numRuns; ++i) {
715 runLevels[i] = line.runs[i].fLevel;
716 }
717 SkAutoSTMalloc<4, int32_t> logicalFromVisual(numRuns);
718 unicode->reorderVisual(runLevels, numRuns, logicalFromVisual);
719
720 for (int i = 0; i < numRuns; ++i) {
721 int logicalIndex = logicalFromVisual[i];
722
723 const auto& run = line.runs[logicalIndex];
724 const SkShaper::RunHandler::RunInfo info = {
725 run.fFont,
726 run.fLevel,
727 run.fAdvance,
728 run.fNumGlyphs,
729 run.fUtf8Range
730 };
731 handler->runInfo(info);
732 }
733 handler->commitRunInfo();
734 for (int i = 0; i < numRuns; ++i) {
735 int logicalIndex = logicalFromVisual[i];
736
737 const auto& run = line.runs[logicalIndex];
738 const SkShaper::RunHandler::RunInfo info = {
739 run.fFont,
740 run.fLevel,
741 run.fAdvance,
742 run.fNumGlyphs,
743 run.fUtf8Range
744 };
745 append(handler, info, run, 0, run.fNumGlyphs);
746 }
747
748 handler->commitLine();
749 }
750
751 struct ShapedRunGlyphIterator {
752 ShapedRunGlyphIterator(const SkTArray<ShapedRun>& origRuns)
753 : fRuns(&origRuns), fRunIndex(0), fGlyphIndex(0)
754 { }
755
756 ShapedRunGlyphIterator(const ShapedRunGlyphIterator& that) = default;
757 ShapedRunGlyphIterator& operator=(const ShapedRunGlyphIterator& that) = default;
758 bool operator==(const ShapedRunGlyphIterator& that) const {
759 return fRuns == that.fRuns &&
760 fRunIndex == that.fRunIndex &&
761 fGlyphIndex == that.fGlyphIndex;
762 }
763 bool operator!=(const ShapedRunGlyphIterator& that) const {
764 return fRuns != that.fRuns ||
765 fRunIndex != that.fRunIndex ||
766 fGlyphIndex != that.fGlyphIndex;
767 }
768
769 ShapedGlyph* next() {
770 const SkTArray<ShapedRun>& runs = *fRuns;
771 SkASSERT(fRunIndex < runs.size());
772 SkASSERT(fGlyphIndex < runs[fRunIndex].fNumGlyphs);
773
774 ++fGlyphIndex;
775 if (fGlyphIndex == runs[fRunIndex].fNumGlyphs) {
776 fGlyphIndex = 0;
777 ++fRunIndex;
778 if (static_cast<size_t>(fRunIndex) >= runs.size()) {
779 return nullptr;
780 }
781 }
782 return &runs[fRunIndex].fGlyphs[fGlyphIndex];
783 }
784
785 ShapedGlyph* current() {
786 const SkTArray<ShapedRun>& runs = *fRuns;
787 if (static_cast<size_t>(fRunIndex) >= runs.size()) {
788 return nullptr;
789 }
790 return &runs[fRunIndex].fGlyphs[fGlyphIndex];
791 }
792
793 const SkTArray<ShapedRun>* fRuns;
794 int fRunIndex;
795 size_t fGlyphIndex;
796 };
797
798 class ShaperHarfBuzz : public SkShaper {
799 public:
800 ShaperHarfBuzz(std::unique_ptr<SkUnicode>,
801 SkUnicodeBreak line,
802 SkUnicodeBreak grapheme,
803 HBBuffer,
804 #ifndef USE_SKIA_TXT
805 sk_sp<SkFontMgr>);
806 #else
807 std::shared_ptr<RSFontMgr>);
808 #endif
809
810 protected:
811 std::unique_ptr<SkUnicode> fUnicode;
812 SkUnicodeBreak fLineBreakIterator;
813 SkUnicodeBreak fGraphemeBreakIterator;
814
815 ShapedRun shape(const char* utf8, size_t utf8Bytes,
816 const char* utf8Start,
817 const char* utf8End,
818 const BiDiRunIterator&,
819 const LanguageRunIterator&,
820 const ScriptRunIterator&,
821 const FontRunIterator&,
822 const Feature*, size_t featuresSize) const;
823 private:
824 #ifndef USE_SKIA_TXT
825 const sk_sp<SkFontMgr> fFontMgr;
826 #else
827 const std::shared_ptr<RSFontMgr> fFontMgr;
828 #endif
829 HBBuffer fBuffer;
830 hb_language_t fUndefinedLanguage;
831
832 void shape(const char* utf8, size_t utf8Bytes,
833 #ifndef USE_SKIA_TXT
834 const SkFont&,
835 #else
836 const RSFont&,
837 #endif
838 bool leftToRight,
839 SkScalar width,
840 RunHandler*) const override;
841
842 void shape(const char* utf8Text, size_t textBytes,
843 FontRunIterator&,
844 BiDiRunIterator&,
845 ScriptRunIterator&,
846 LanguageRunIterator&,
847 SkScalar width,
848 RunHandler*) const override;
849
850 void shape(const char* utf8Text, size_t textBytes,
851 FontRunIterator&,
852 BiDiRunIterator&,
853 ScriptRunIterator&,
854 LanguageRunIterator&,
855 const Feature*, size_t featuresSize,
856 SkScalar width,
857 RunHandler*) const override;
858
859 virtual void wrap(char const * const utf8, size_t utf8Bytes,
860 const BiDiRunIterator&,
861 const LanguageRunIterator&,
862 const ScriptRunIterator&,
863 const FontRunIterator&,
864 RunIteratorQueue& runSegmenter,
865 const Feature*, size_t featuresSize,
866 SkScalar width,
867 RunHandler*) const = 0;
868 };
869
870 class ShaperDrivenWrapper : public ShaperHarfBuzz {
871 public:
872 using ShaperHarfBuzz::ShaperHarfBuzz;
873 private:
874 void wrap(char const * const utf8, size_t utf8Bytes,
875 const BiDiRunIterator&,
876 const LanguageRunIterator&,
877 const ScriptRunIterator&,
878 const FontRunIterator&,
879 RunIteratorQueue& runSegmenter,
880 const Feature*, size_t featuresSize,
881 SkScalar width,
882 RunHandler*) const override;
883 };
884
885 class ShapeThenWrap : public ShaperHarfBuzz {
886 public:
887 using ShaperHarfBuzz::ShaperHarfBuzz;
888 private:
889 void wrap(char const * const utf8, size_t utf8Bytes,
890 const BiDiRunIterator&,
891 const LanguageRunIterator&,
892 const ScriptRunIterator&,
893 const FontRunIterator&,
894 RunIteratorQueue& runSegmenter,
895 const Feature*, size_t featuresSize,
896 SkScalar width,
897 RunHandler*) const override;
898 };
899
900 class ShapeDontWrapOrReorder : public ShaperHarfBuzz {
901 public:
902 using ShaperHarfBuzz::ShaperHarfBuzz;
903 private:
904 void wrap(char const * const utf8, size_t utf8Bytes,
905 const BiDiRunIterator&,
906 const LanguageRunIterator&,
907 const ScriptRunIterator&,
908 const FontRunIterator&,
909 RunIteratorQueue& runSegmenter,
910 const Feature*, size_t featuresSize,
911 SkScalar width,
912 RunHandler*) const override;
913 };
914
915 #ifndef USE_SKIA_TXT
916 static std::unique_ptr<SkShaper> MakeHarfBuzz(sk_sp<SkFontMgr> fontmgr, bool correct) {
917 #else
918 static std::unique_ptr<SkShaper> MakeHarfBuzz(std::shared_ptr<RSFontMgr> fontmgr, bool correct) {
919 #endif
920 HBBuffer buffer(hb_buffer_create());
921 if (!buffer) {
922 SkDEBUGF("Could not create hb_buffer");
923 return nullptr;
924 }
925
926 auto unicode = SkUnicode::Make();
927 if (!unicode) {
928 return nullptr;
929 }
930
931 const auto lname = std::locale().name();
932 auto lineIter = unicode->makeBreakIterator(lname.c_str(), SkUnicode::BreakType::kLines);
933 if (!lineIter) {
934 return nullptr;
935 }
936 auto graphIter = unicode->makeBreakIterator(lname.c_str(), SkUnicode::BreakType::kGraphemes);
937 if (!graphIter) {
938 return nullptr;
939 }
940
941 if (correct) {
942 return std::make_unique<ShaperDrivenWrapper>(std::move(unicode),
943 std::move(lineIter), std::move(graphIter), std::move(buffer), std::move(fontmgr));
944 } else {
945 return std::make_unique<ShapeThenWrap>(std::move(unicode),
946 std::move(lineIter), std::move(graphIter), std::move(buffer), std::move(fontmgr));
947 }
948 }
949
950 #ifndef USE_SKIA_TXT
951 ShaperHarfBuzz::ShaperHarfBuzz(std::unique_ptr<SkUnicode> unicode,
952 SkUnicodeBreak lineIter, SkUnicodeBreak graphIter, HBBuffer buffer, sk_sp<SkFontMgr> fontmgr)
953 #else
954 ShaperHarfBuzz::ShaperHarfBuzz(std::unique_ptr<SkUnicode> unicode,
955 SkUnicodeBreak lineIter, SkUnicodeBreak graphIter, HBBuffer buffer, std::shared_ptr<RSFontMgr> fontmgr)
956 #endif
957 : fUnicode(std::move(unicode))
958 , fLineBreakIterator(std::move(lineIter))
959 , fGraphemeBreakIterator(std::move(graphIter))
960 , fFontMgr(std::move(fontmgr))
961 , fBuffer(std::move(buffer))
962 , fUndefinedLanguage(hb_language_from_string("und", -1))
963 { }
964
965 void ShaperHarfBuzz::shape(const char* utf8, size_t utf8Bytes,
966 #ifndef USE_SKIA_TXT
967 const SkFont& srcFont,
968 #else
969 const RSFont& srcFont,
970 #endif
971 bool leftToRight,
972 SkScalar width,
973 RunHandler* handler) const
974 {
975 SkBidiIterator::Level defaultLevel = leftToRight ? SkBidiIterator::kLTR : SkBidiIterator::kRTL;
976 std::unique_ptr<BiDiRunIterator> bidi(MakeSkUnicodeBidiRunIterator(fUnicode.get(),
977 utf8,
978 utf8Bytes,
979 defaultLevel));
980
981 if (!bidi) {
982 return;
983 }
984
985 std::unique_ptr<LanguageRunIterator> language(MakeStdLanguageRunIterator(utf8, utf8Bytes));
986 if (!language) {
987 return;
988 }
989
990 std::unique_ptr<ScriptRunIterator> script(MakeSkUnicodeHbScriptRunIterator(utf8, utf8Bytes));
991 if (!script) {
992 return;
993 }
994
995 #ifndef USE_SKIA_TXT
996 std::unique_ptr<FontRunIterator> font(
997 MakeFontMgrRunIterator(utf8, utf8Bytes, srcFont,
998 fFontMgr ? fFontMgr : SkFontMgr::RefDefault()));
999 #else
1000 std::unique_ptr<FontRunIterator> font(
1001 MakeFontMgrRunIterator(utf8, utf8Bytes, srcFont,
1002 fFontMgr ? fFontMgr : RSFontMgr::CreateDefaultFontMgr()));
1003 #endif
1004 if (!font) {
1005 return;
1006 }
1007
1008 this->shape(utf8, utf8Bytes, *font, *bidi, *script, *language, width, handler);
1009 }
1010
1011 void ShaperHarfBuzz::shape(const char* utf8, size_t utf8Bytes,
1012 FontRunIterator& font,
1013 BiDiRunIterator& bidi,
1014 ScriptRunIterator& script,
1015 LanguageRunIterator& language,
1016 SkScalar width,
1017 RunHandler* handler) const
1018 {
1019 this->shape(utf8, utf8Bytes, font, bidi, script, language, nullptr, 0, width, handler);
1020 }
1021
1022 void ShaperHarfBuzz::shape(const char* utf8, size_t utf8Bytes,
1023 FontRunIterator& font,
1024 BiDiRunIterator& bidi,
1025 ScriptRunIterator& script,
1026 LanguageRunIterator& language,
1027 const Feature* features, size_t featuresSize,
1028 SkScalar width,
1029 RunHandler* handler) const
1030 {
1031 SkASSERT(handler);
1032 RunIteratorQueue runSegmenter;
1033 runSegmenter.insert(&font, 3); // The font iterator is always run last in case of tie.
1034 runSegmenter.insert(&bidi, 2);
1035 runSegmenter.insert(&script, 1);
1036 runSegmenter.insert(&language, 0);
1037
1038 this->wrap(utf8, utf8Bytes, bidi, language, script, font, runSegmenter,
1039 features, featuresSize, width, handler);
1040 }
1041
1042 void ShaperDrivenWrapper::wrap(char const * const utf8, size_t utf8Bytes,
1043 const BiDiRunIterator& bidi,
1044 const LanguageRunIterator& language,
1045 const ScriptRunIterator& script,
1046 const FontRunIterator& font,
1047 RunIteratorQueue& runSegmenter,
1048 const Feature* features, size_t featuresSize,
1049 SkScalar width,
1050 RunHandler* handler) const
1051 {
1052 ShapedLine line;
1053
1054 const char* utf8Start = nullptr;
1055 const char* utf8End = utf8;
1056 while (runSegmenter.advanceRuns()) { // For each item
1057 utf8Start = utf8End;
1058 utf8End = utf8 + runSegmenter.endOfCurrentRun();
1059
1060 #ifndef USE_SKIA_TXT
1061 ShapedRun model(RunHandler::Range(), SkFont(), 0, nullptr, 0);
1062 #else
1063 ShapedRun model(RunHandler::Range(), RSFont(), 0, nullptr, 0);
1064 #endif
1065 bool modelNeedsRegenerated = true;
1066 int modelGlyphOffset = 0;
1067
1068 struct TextProps {
1069 int glyphLen = 0;
1070 SkVector advance = {0, 0};
1071 };
1072 // map from character position to [safe to break, glyph position, advance]
1073 std::unique_ptr<TextProps[]> modelText;
1074 int modelTextOffset = 0;
1075 SkVector modelAdvanceOffset = {0, 0};
1076
1077 while (utf8Start < utf8End) { // While there are still code points left in this item
1078 size_t utf8runLength = utf8End - utf8Start;
1079 if (modelNeedsRegenerated) {
1080 model = shape(utf8, utf8Bytes,
1081 utf8Start, utf8End,
1082 bidi, language, script, font,
1083 features, featuresSize);
1084 modelGlyphOffset = 0;
1085
1086 SkVector advance = {0, 0};
1087 modelText = std::make_unique<TextProps[]>(utf8runLength + 1);
1088 size_t modelStartCluster = utf8Start - utf8;
1089 size_t previousCluster = 0;
1090 for (size_t i = 0; i < model.fNumGlyphs; ++i) {
1091 SkASSERT(modelStartCluster <= model.fGlyphs[i].fCluster);
1092 SkASSERT( model.fGlyphs[i].fCluster < (size_t)(utf8End - utf8));
1093 if (!model.fGlyphs[i].fUnsafeToBreak) {
1094 // Store up to the first glyph in the cluster.
1095 size_t currentCluster = model.fGlyphs[i].fCluster - modelStartCluster;
1096 if (previousCluster != currentCluster) {
1097 previousCluster = currentCluster;
1098 modelText[currentCluster].glyphLen = i;
1099 modelText[currentCluster].advance = advance;
1100 }
1101 }
1102 advance += model.fGlyphs[i].fAdvance;
1103 }
1104 // Assume it is always safe to break after the end of an item
1105 modelText[utf8runLength].glyphLen = model.fNumGlyphs;
1106 modelText[utf8runLength].advance = model.fAdvance;
1107 modelTextOffset = 0;
1108 modelAdvanceOffset = {0, 0};
1109 modelNeedsRegenerated = false;
1110 }
1111
1112 // TODO: break iterator per item, but just reset position if needed?
1113 // Maybe break iterator with model?
1114 if (!fLineBreakIterator->setText(utf8Start, utf8runLength)) {
1115 return;
1116 }
1117 SkBreakIterator& breakIterator = *fLineBreakIterator;
1118
1119 #ifndef USE_SKIA_TXT
1120 ShapedRun best(RunHandler::Range(), SkFont(), 0, nullptr, 0,
1121 { SK_ScalarNegativeInfinity, SK_ScalarNegativeInfinity });
1122 #else
1123 ShapedRun best(RunHandler::Range(), RSFont(), 0, nullptr, 0,
1124 { SK_ScalarNegativeInfinity, SK_ScalarNegativeInfinity });
1125 #endif
1126 bool bestIsInvalid = true;
1127 bool bestUsesModelForGlyphs = false;
1128 SkScalar widthLeft = width - line.fAdvance.fX;
1129
1130 for (int32_t breakIteratorCurrent = breakIterator.next();
1131 !breakIterator.isDone();
1132 breakIteratorCurrent = breakIterator.next())
1133 {
1134 // TODO: if past a safe to break, future safe to break will be at least as long
1135
1136 // TODO: adjust breakIteratorCurrent by ignorable whitespace
1137 bool candidateUsesModelForGlyphs = false;
1138 ShapedRun candidate = [&](const TextProps& props){
1139 if (props.glyphLen) {
1140 candidateUsesModelForGlyphs = true;
1141 return ShapedRun(RunHandler::Range(utf8Start - utf8, breakIteratorCurrent),
1142 font.currentFont(), bidi.currentLevel(),
1143 std::unique_ptr<ShapedGlyph[]>(),
1144 props.glyphLen - modelGlyphOffset,
1145 props.advance - modelAdvanceOffset);
1146 } else {
1147 return shape(utf8, utf8Bytes,
1148 utf8Start, utf8Start + breakIteratorCurrent,
1149 bidi, language, script, font,
1150 features, featuresSize);
1151 }
1152 }(modelText[breakIteratorCurrent + modelTextOffset]);
1153 auto score = [widthLeft](const ShapedRun& run) -> SkScalar {
1154 if (run.fAdvance.fX < widthLeft) {
1155 return run.fUtf8Range.size();
1156 } else {
1157 return widthLeft - run.fAdvance.fX;
1158 }
1159 };
1160 if (bestIsInvalid || score(best) < score(candidate)) {
1161 best = std::move(candidate);
1162 bestIsInvalid = false;
1163 bestUsesModelForGlyphs = candidateUsesModelForGlyphs;
1164 }
1165 }
1166
1167 // If nothing fit (best score is negative) and the line is not empty
1168 if (width < line.fAdvance.fX + best.fAdvance.fX && !line.runs.empty()) {
1169 emit(fUnicode.get(), line, handler);
1170 line.runs.reset();
1171 line.fAdvance = {0, 0};
1172 } else {
1173 if (bestUsesModelForGlyphs) {
1174 best.fGlyphs = std::make_unique<ShapedGlyph[]>(best.fNumGlyphs);
1175 memcpy(best.fGlyphs.get(), model.fGlyphs.get() + modelGlyphOffset,
1176 best.fNumGlyphs * sizeof(ShapedGlyph));
1177 modelGlyphOffset += best.fNumGlyphs;
1178 modelTextOffset += best.fUtf8Range.size();
1179 modelAdvanceOffset += best.fAdvance;
1180 } else {
1181 modelNeedsRegenerated = true;
1182 }
1183 utf8Start += best.fUtf8Range.size();
1184 line.fAdvance += best.fAdvance;
1185 line.runs.emplace_back(std::move(best));
1186
1187 // If item broken, emit line (prevent remainder from accidentally fitting)
1188 if (utf8Start != utf8End) {
1189 emit(fUnicode.get(), line, handler);
1190 line.runs.reset();
1191 line.fAdvance = {0, 0};
1192 }
1193 }
1194 }
1195 }
1196 emit(fUnicode.get(), line, handler);
1197 }
1198
1199 void ShapeThenWrap::wrap(char const * const utf8, size_t utf8Bytes,
1200 const BiDiRunIterator& bidi,
1201 const LanguageRunIterator& language,
1202 const ScriptRunIterator& script,
1203 const FontRunIterator& font,
1204 RunIteratorQueue& runSegmenter,
1205 const Feature* features, size_t featuresSize,
1206 SkScalar width,
1207 RunHandler* handler) const
1208 {
1209 SkTArray<ShapedRun> runs;
1210 {
1211 if (!fLineBreakIterator->setText(utf8, utf8Bytes)) {
1212 return;
1213 }
1214 if (!fGraphemeBreakIterator->setText(utf8, utf8Bytes)) {
1215 return;
1216 }
1217
1218 SkBreakIterator& lineBreakIterator = *fLineBreakIterator;
1219 SkBreakIterator& graphemeBreakIterator = *fGraphemeBreakIterator;
1220 const char* utf8Start = nullptr;
1221 const char* utf8End = utf8;
1222 while (runSegmenter.advanceRuns()) {
1223 utf8Start = utf8End;
1224 utf8End = utf8 + runSegmenter.endOfCurrentRun();
1225
1226 runs.emplace_back(shape(utf8, utf8Bytes,
1227 utf8Start, utf8End,
1228 bidi, language, script, font,
1229 features, featuresSize));
1230 ShapedRun& run = runs.back();
1231
1232 uint32_t previousCluster = 0xFFFFFFFF;
1233 for (size_t i = 0; i < run.fNumGlyphs; ++i) {
1234 ShapedGlyph& glyph = run.fGlyphs[i];
1235 int32_t glyphCluster = glyph.fCluster;
1236
1237 int32_t lineBreakIteratorCurrent = lineBreakIterator.current();
1238 while (!lineBreakIterator.isDone() && lineBreakIteratorCurrent < glyphCluster)
1239 {
1240 lineBreakIteratorCurrent = lineBreakIterator.next();
1241 }
1242 glyph.fMayLineBreakBefore = glyph.fCluster != previousCluster &&
1243 lineBreakIteratorCurrent == glyphCluster;
1244
1245 int32_t graphemeBreakIteratorCurrent = graphemeBreakIterator.current();
1246 while (!graphemeBreakIterator.isDone() && graphemeBreakIteratorCurrent < glyphCluster)
1247 {
1248 graphemeBreakIteratorCurrent = graphemeBreakIterator.next();
1249 }
1250 glyph.fGraphemeBreakBefore = glyph.fCluster != previousCluster &&
1251 graphemeBreakIteratorCurrent == glyphCluster;
1252
1253 previousCluster = glyph.fCluster;
1254 }
1255 }
1256 }
1257
1258 // Iterate over the glyphs in logical order to find potential line lengths.
1259 {
1260 /** The position of the beginning of the line. */
1261 ShapedRunGlyphIterator beginning(runs);
1262
1263 /** The position of the candidate line break. */
1264 ShapedRunGlyphIterator candidateLineBreak(runs);
1265 SkScalar candidateLineBreakWidth = 0;
1266
1267 /** The position of the candidate grapheme break. */
1268 ShapedRunGlyphIterator candidateGraphemeBreak(runs);
1269 SkScalar candidateGraphemeBreakWidth = 0;
1270
1271 /** The position of the current location. */
1272 ShapedRunGlyphIterator current(runs);
1273 SkScalar currentWidth = 0;
1274 while (ShapedGlyph* glyph = current.current()) {
1275 // 'Break' at graphemes until a line boundary, then only at line boundaries.
1276 // Only break at graphemes if no line boundary is valid.
1277 if (current != beginning) {
1278 if (glyph->fGraphemeBreakBefore || glyph->fMayLineBreakBefore) {
1279 // TODO: preserve line breaks <= grapheme breaks
1280 // and prevent line breaks inside graphemes
1281 candidateGraphemeBreak = current;
1282 candidateGraphemeBreakWidth = currentWidth;
1283 if (glyph->fMayLineBreakBefore) {
1284 candidateLineBreak = current;
1285 candidateLineBreakWidth = currentWidth;
1286 }
1287 }
1288 }
1289
1290 SkScalar glyphWidth = glyph->fAdvance.fX;
1291 // Break when overwidth, the glyph has a visual representation, and some space is used.
1292 if (width < currentWidth + glyphWidth && glyph->fHasVisual && candidateGraphemeBreakWidth > 0){
1293 if (candidateLineBreak != beginning) {
1294 beginning = candidateLineBreak;
1295 currentWidth -= candidateLineBreakWidth;
1296 candidateGraphemeBreakWidth -= candidateLineBreakWidth;
1297 candidateLineBreakWidth = 0;
1298 } else if (candidateGraphemeBreak != beginning) {
1299 beginning = candidateGraphemeBreak;
1300 candidateLineBreak = beginning;
1301 currentWidth -= candidateGraphemeBreakWidth;
1302 candidateGraphemeBreakWidth = 0;
1303 candidateLineBreakWidth = 0;
1304 } else {
1305 SK_ABORT("");
1306 }
1307
1308 if (width < currentWidth) {
1309 if (width < candidateGraphemeBreakWidth) {
1310 candidateGraphemeBreak = candidateLineBreak;
1311 candidateGraphemeBreakWidth = candidateLineBreakWidth;
1312 }
1313 current = candidateGraphemeBreak;
1314 currentWidth = candidateGraphemeBreakWidth;
1315 }
1316
1317 glyph = beginning.current();
1318 if (glyph) {
1319 glyph->fMustLineBreakBefore = true;
1320 }
1321
1322 } else {
1323 current.next();
1324 currentWidth += glyphWidth;
1325 }
1326 }
1327 }
1328
1329 // Reorder the runs and glyphs per line and write them out.
1330 {
1331 ShapedRunGlyphIterator previousBreak(runs);
1332 ShapedRunGlyphIterator glyphIterator(runs);
1333 int previousRunIndex = -1;
1334 while (glyphIterator.current()) {
1335 const ShapedRunGlyphIterator current = glyphIterator;
1336 ShapedGlyph* nextGlyph = glyphIterator.next();
1337
1338 if (previousRunIndex != current.fRunIndex) {
1339 #ifndef USE_SKIA_TXT
1340 SkFontMetrics metrics;
1341 runs[current.fRunIndex].fFont.getMetrics(&metrics);
1342 #else
1343 RSFontMetrics metrics;
1344 runs[current.fRunIndex].fFont.GetMetrics(&metrics);
1345 #endif
1346 previousRunIndex = current.fRunIndex;
1347 }
1348
1349 // Nothing can be written until the baseline is known.
1350 if (!(nextGlyph == nullptr || nextGlyph->fMustLineBreakBefore)) {
1351 continue;
1352 }
1353
1354 int numRuns = current.fRunIndex - previousBreak.fRunIndex + 1;
1355 SkAutoSTMalloc<4, SkBidiIterator::Level> runLevels(numRuns);
1356 for (int i = 0; i < numRuns; ++i) {
1357 runLevels[i] = runs[previousBreak.fRunIndex + i].fLevel;
1358 }
1359 SkAutoSTMalloc<4, int32_t> logicalFromVisual(numRuns);
1360 fUnicode->reorderVisual(runLevels, numRuns, logicalFromVisual);
1361
1362 // step through the runs in reverse visual order and the glyphs in reverse logical order
1363 // until a visible glyph is found and force them to the end of the visual line.
1364
1365 handler->beginLine();
1366
1367 struct SubRun { const ShapedRun& run; size_t startGlyphIndex; size_t endGlyphIndex; };
1368 auto makeSubRun = [&runs, &previousBreak, ¤t, &logicalFromVisual](size_t visualIndex){
1369 int logicalIndex = previousBreak.fRunIndex + logicalFromVisual[visualIndex];
1370 const auto& run = runs[logicalIndex];
1371 size_t startGlyphIndex = (logicalIndex == previousBreak.fRunIndex)
1372 ? previousBreak.fGlyphIndex
1373 : 0;
1374 size_t endGlyphIndex = (logicalIndex == current.fRunIndex)
1375 ? current.fGlyphIndex + 1
1376 : run.fNumGlyphs;
1377 return SubRun{ run, startGlyphIndex, endGlyphIndex };
1378 };
1379 auto makeRunInfo = [](const SubRun& sub) {
1380 uint32_t startUtf8 = sub.run.fGlyphs[sub.startGlyphIndex].fCluster;
1381 uint32_t endUtf8 = (sub.endGlyphIndex < sub.run.fNumGlyphs)
1382 ? sub.run.fGlyphs[sub.endGlyphIndex].fCluster
1383 : sub.run.fUtf8Range.end();
1384
1385 SkVector advance = SkVector::Make(0, 0);
1386 for (size_t i = sub.startGlyphIndex; i < sub.endGlyphIndex; ++i) {
1387 advance += sub.run.fGlyphs[i].fAdvance;
1388 }
1389
1390 return RunHandler::RunInfo{
1391 sub.run.fFont,
1392 sub.run.fLevel,
1393 advance,
1394 sub.endGlyphIndex - sub.startGlyphIndex,
1395 RunHandler::Range(startUtf8, endUtf8 - startUtf8)
1396 };
1397 };
1398
1399 for (int i = 0; i < numRuns; ++i) {
1400 handler->runInfo(makeRunInfo(makeSubRun(i)));
1401 }
1402 handler->commitRunInfo();
1403 for (int i = 0; i < numRuns; ++i) {
1404 SubRun sub = makeSubRun(i);
1405 append(handler, makeRunInfo(sub), sub.run, sub.startGlyphIndex, sub.endGlyphIndex);
1406 }
1407
1408 handler->commitLine();
1409
1410 previousRunIndex = -1;
1411 previousBreak = glyphIterator;
1412 }
1413 }
1414 }
1415
1416 void ShapeDontWrapOrReorder::wrap(char const * const utf8, size_t utf8Bytes,
1417 const BiDiRunIterator& bidi,
1418 const LanguageRunIterator& language,
1419 const ScriptRunIterator& script,
1420 const FontRunIterator& font,
1421 RunIteratorQueue& runSegmenter,
1422 const Feature* features, size_t featuresSize,
1423 SkScalar width,
1424 RunHandler* handler) const
1425 {
1426 sk_ignore_unused_variable(width);
1427 SkTArray<ShapedRun> runs;
1428
1429 const char* utf8Start = nullptr;
1430 const char* utf8End = utf8;
1431 while (runSegmenter.advanceRuns()) {
1432 utf8Start = utf8End;
1433 utf8End = utf8 + runSegmenter.endOfCurrentRun();
1434
1435 runs.emplace_back(shape(utf8, utf8Bytes,
1436 utf8Start, utf8End,
1437 bidi, language, script, font,
1438 features, featuresSize));
1439 }
1440
1441 handler->beginLine();
1442 for (const auto& run : runs) {
1443 const RunHandler::RunInfo info = {
1444 run.fFont,
1445 run.fLevel,
1446 run.fAdvance,
1447 run.fNumGlyphs,
1448 run.fUtf8Range
1449 };
1450 handler->runInfo(info);
1451 }
1452 handler->commitRunInfo();
1453 for (const auto& run : runs) {
1454 const RunHandler::RunInfo info = {
1455 run.fFont,
1456 run.fLevel,
1457 run.fAdvance,
1458 run.fNumGlyphs,
1459 run.fUtf8Range
1460 };
1461 append(handler, info, run, 0, run.fNumGlyphs);
1462 }
1463 handler->commitLine();
1464 }
1465
1466 class HBLockedFaceCache {
1467 public:
1468 HBLockedFaceCache(SkLRUCache<uint32_t, HBFont>& lruCache, SkMutex& mutex)
1469 : fLRUCache(lruCache), fMutex(mutex)
1470 {
1471 fMutex.acquire();
1472 }
1473 HBLockedFaceCache(const HBLockedFaceCache&) = delete;
1474 HBLockedFaceCache& operator=(const HBLockedFaceCache&) = delete;
1475 // Required until C++17 copy elision
1476 HBLockedFaceCache(HBLockedFaceCache&&) = default;
1477 HBLockedFaceCache& operator=(HBLockedFaceCache&&) = delete;
1478
1479 ~HBLockedFaceCache() {
1480 fMutex.release();
1481 }
1482
1483 HBFont* find(uint32_t fontId) {
1484 return fLRUCache.find(fontId);
1485 }
1486 HBFont* insert(uint32_t fontId, HBFont hbFont) {
1487 return fLRUCache.insert(fontId, std::move(hbFont));
1488 }
1489 void reset() {
1490 fLRUCache.reset();
1491 }
1492 private:
1493 SkLRUCache<uint32_t, HBFont>& fLRUCache;
1494 SkMutex& fMutex;
1495 };
1496 static HBLockedFaceCache get_hbFace_cache() {
1497 static SkMutex gHBFaceCacheMutex;
1498 static SkLRUCache<uint32_t, HBFont> gHBFaceCache(100);
1499 return HBLockedFaceCache(gHBFaceCache, gHBFaceCacheMutex);
1500 }
1501
1502 ShapedRun ShaperHarfBuzz::shape(char const * const utf8,
1503 size_t const utf8Bytes,
1504 char const * const utf8Start,
1505 char const * const utf8End,
1506 const BiDiRunIterator& bidi,
1507 const LanguageRunIterator& language,
1508 const ScriptRunIterator& script,
1509 const FontRunIterator& font,
1510 Feature const * const features, size_t const featuresSize) const
1511 {
1512 size_t utf8runLength = utf8End - utf8Start;
1513 ShapedRun run(RunHandler::Range(utf8Start - utf8, utf8runLength),
1514 font.currentFont(), bidi.currentLevel(), nullptr, 0);
1515
1516 hb_buffer_t* buffer = fBuffer.get();
1517 SkAutoTCallVProc<hb_buffer_t, hb_buffer_clear_contents> autoClearBuffer(buffer);
1518 hb_buffer_set_content_type(buffer, HB_BUFFER_CONTENT_TYPE_UNICODE);
1519 hb_buffer_set_cluster_level(buffer, HB_BUFFER_CLUSTER_LEVEL_MONOTONE_CHARACTERS);
1520
1521 // Documentation for HB_BUFFER_FLAG_BOT/EOT at 763e5466c0a03a7c27020e1e2598e488612529a7.
1522 // Currently BOT forces a dotted circle when first codepoint is a mark; EOT has no effect.
1523 // Avoid adding dotted circle, re-evaluate if BOT/EOT change. See https://skbug.com/9618.
1524 // hb_buffer_set_flags(buffer, HB_BUFFER_FLAG_BOT | HB_BUFFER_FLAG_EOT);
1525
1526 // Add precontext.
1527 hb_buffer_add_utf8(buffer, utf8, utf8Start - utf8, utf8Start - utf8, 0);
1528
1529 // Populate the hb_buffer directly with utf8 cluster indexes.
1530 const char* utf8Current = utf8Start;
1531 while (utf8Current < utf8End) {
1532 unsigned int cluster = utf8Current - utf8;
1533 hb_codepoint_t u = utf8_next(&utf8Current, utf8End);
1534 hb_buffer_add(buffer, u, cluster);
1535 }
1536
1537 // Add postcontext.
1538 hb_buffer_add_utf8(buffer, utf8Current, utf8 + utf8Bytes - utf8Current, 0, 0);
1539
1540 hb_direction_t direction = is_LTR(bidi.currentLevel()) ? HB_DIRECTION_LTR:HB_DIRECTION_RTL;
1541 hb_buffer_set_direction(buffer, direction);
1542 hb_buffer_set_script(buffer, hb_script_from_iso15924_tag((hb_tag_t)script.currentScript()));
1543 // Buffers with HB_LANGUAGE_INVALID race since hb_language_get_default is not thread safe.
1544 // The user must provide a language, but may provide data hb_language_from_string cannot use.
1545 // Use "und" for the undefined language in this case (RFC5646 4.1 5).
1546 hb_language_t hbLanguage = hb_language_from_string(language.currentLanguage(), -1);
1547 if (hbLanguage == HB_LANGUAGE_INVALID) {
1548 hbLanguage = fUndefinedLanguage;
1549 }
1550 hb_buffer_set_language(buffer, hbLanguage);
1551 hb_buffer_guess_segment_properties(buffer);
1552
1553 // TODO: better cache HBFace (data) / hbfont (typeface)
1554 // An HBFace is expensive (it sanitizes the bits).
1555 // An HBFont is fairly inexpensive.
1556 // An HBFace is actually tied to the data, not the typeface.
1557 // The size of 100 here is completely arbitrary and used to match libtxt.
1558 HBFont hbFont;
1559 {
1560 HBLockedFaceCache cache = get_hbFace_cache();
1561 #ifndef USE_SKIA_TXT
1562 uint32_t dataId = font.currentFont().getTypeface()->uniqueID();
1563 #else
1564 uint32_t dataId = const_cast<RSFont&>(font.currentFont()).GetTypeface()->GetUniqueID();
1565 #endif
1566 HBFont* typefaceFontCached = cache.find(dataId);
1567 if (!typefaceFontCached) {
1568 #ifndef USE_SKIA_TXT
1569 HBFont typefaceFont(create_typeface_hb_font(*font.currentFont().getTypeface()));
1570 #else
1571 HBFont typefaceFont(create_typeface_hb_font(*const_cast<RSFont&>(font.currentFont()).GetTypeface()));
1572 #endif
1573 typefaceFontCached = cache.insert(dataId, std::move(typefaceFont));
1574 }
1575 hbFont = create_sub_hb_font(font.currentFont(), *typefaceFontCached);
1576 }
1577 if (!hbFont) {
1578 return run;
1579 }
1580
1581 SkSTArray<32, hb_feature_t> hbFeatures;
1582 for (const auto& feature : SkMakeSpan(features, featuresSize)) {
1583 if (feature.end < SkTo<size_t>(utf8Start - utf8) ||
1584 SkTo<size_t>(utf8End - utf8) <= feature.start)
1585 {
1586 continue;
1587 }
1588 if (feature.start <= SkTo<size_t>(utf8Start - utf8) &&
1589 SkTo<size_t>(utf8End - utf8) <= feature.end)
1590 {
1591 hbFeatures.push_back({ (hb_tag_t)feature.tag, feature.value,
1592 HB_FEATURE_GLOBAL_START, HB_FEATURE_GLOBAL_END});
1593 } else {
1594 hbFeatures.push_back({ (hb_tag_t)feature.tag, feature.value,
1595 SkTo<unsigned>(feature.start), SkTo<unsigned>(feature.end)});
1596 }
1597 }
1598
1599 hb_shape(hbFont.get(), buffer, hbFeatures.data(), hbFeatures.size());
1600 unsigned len = hb_buffer_get_length(buffer);
1601 if (len == 0) {
1602 return run;
1603 }
1604
1605 if (direction == HB_DIRECTION_RTL) {
1606 // Put the clusters back in logical order.
1607 // Note that the advances remain ltr.
1608 hb_buffer_reverse(buffer);
1609 }
1610 hb_glyph_info_t* info = hb_buffer_get_glyph_infos(buffer, nullptr);
1611 hb_glyph_position_t* pos = hb_buffer_get_glyph_positions(buffer, nullptr);
1612
1613 run = ShapedRun(RunHandler::Range(utf8Start - utf8, utf8runLength),
1614 font.currentFont(), bidi.currentLevel(),
1615 std::unique_ptr<ShapedGlyph[]>(new ShapedGlyph[len]), len);
1616
1617 // Undo skhb_position with (1.0/(1<<16)) and scale as needed.
1618 SkAutoSTArray<32, SkGlyphID> glyphIDs(len);
1619 for (unsigned i = 0; i < len; i++) {
1620 glyphIDs[i] = info[i].codepoint;
1621 }
1622 #ifndef USE_SKIA_TXT
1623 SkAutoSTArray<32, SkRect> glyphBounds(len);
1624 SkPaint p;
1625 run.fFont.getBounds(glyphIDs.get(), len, glyphBounds.get(), &p);
1626 #else
1627 SkAutoSTArray<32, RSRect> glyphBounds(len);
1628 run.fFont.GetWidths(glyphIDs.get(), len, nullptr, glyphBounds.get());
1629 #endif
1630
1631 #ifndef USE_SKIA_TXT
1632 double SkScalarFromHBPosX = +(1.52587890625e-5) * run.fFont.getScaleX();
1633 #else
1634 double SkScalarFromHBPosX = +(1.52587890625e-5) * run.fFont.GetScaleX();
1635 #endif
1636 double SkScalarFromHBPosY = -(1.52587890625e-5); // HarfBuzz y-up, Skia y-down
1637 SkVector runAdvance = { 0, 0 };
1638 for (unsigned i = 0; i < len; i++) {
1639 ShapedGlyph& glyph = run.fGlyphs[i];
1640 glyph.fID = info[i].codepoint;
1641 glyph.fCluster = info[i].cluster;
1642 glyph.fOffset.fX = pos[i].x_offset * SkScalarFromHBPosX;
1643 glyph.fOffset.fY = pos[i].y_offset * SkScalarFromHBPosY;
1644 glyph.fAdvance.fX = pos[i].x_advance * SkScalarFromHBPosX;
1645 glyph.fAdvance.fY = pos[i].y_advance * SkScalarFromHBPosY;
1646
1647 #ifndef USE_SKIA_TXT
1648 glyph.fHasVisual = !glyphBounds[i].isEmpty(); //!font->currentTypeface()->glyphBoundsAreZero(glyph.fID);
1649 #else
1650 glyph.fHasVisual = !glyphBounds[i].IsEmpty(); //!font->currentTypeface()->glyphBoundsAreZero(glyph.fID);
1651 #endif
1652 #if SK_HB_VERSION_CHECK(1, 5, 0)
1653 glyph.fUnsafeToBreak = info[i].mask & HB_GLYPH_FLAG_UNSAFE_TO_BREAK;
1654 #else
1655 glyph.fUnsafeToBreak = false;
1656 #endif
1657 glyph.fMustLineBreakBefore = false;
1658
1659 runAdvance += glyph.fAdvance;
1660 }
1661 run.fAdvance = runAdvance;
1662
1663 return run;
1664 }
1665
1666 } // namespace
1667
1668 #ifdef USE_SKIA_TXT
1669 namespace SkiaRsText {
1670 #endif
1671 std::unique_ptr<SkShaper::BiDiRunIterator>
1672 SkShaper::MakeIcuBiDiRunIterator(const char* utf8, size_t utf8Bytes, uint8_t bidiLevel) {
1673 auto unicode = SkUnicode::Make();
1674 if (!unicode) {
1675 return nullptr;
1676 }
1677 return SkShaper::MakeSkUnicodeBidiRunIterator(unicode.get(),
1678 utf8,
1679 utf8Bytes,
1680 bidiLevel);
1681 }
1682
1683 std::unique_ptr<SkShaper::BiDiRunIterator>
1684 SkShaper::MakeSkUnicodeBidiRunIterator(SkUnicode* unicode, const char* utf8, size_t utf8Bytes, uint8_t bidiLevel) {
1685 // ubidi only accepts utf16 (though internally it basically works on utf32 chars).
1686 // We want an ubidi_setPara(UBiDi*, UText*, UBiDiLevel, UBiDiLevel*, UErrorCode*);
1687 if (!SkTFitsIn<int32_t>(utf8Bytes)) {
1688 SkDEBUGF("Bidi error: text too long");
1689 return nullptr;
1690 }
1691
1692 int32_t utf16Units = SkUTF::UTF8ToUTF16(nullptr, 0, utf8, utf8Bytes);
1693 if (utf16Units < 0) {
1694 SkDEBUGF("Invalid utf8 input\n");
1695 return nullptr;
1696 }
1697
1698 std::unique_ptr<uint16_t[]> utf16(new uint16_t[utf16Units]);
1699 (void)SkUTF::UTF8ToUTF16(utf16.get(), utf16Units, utf8, utf8Bytes);
1700
1701 auto bidiDir = (bidiLevel % 2 == 0) ? SkBidiIterator::kLTR : SkBidiIterator::kRTL;
1702 SkUnicodeBidi bidi = unicode->makeBidiIterator(utf16.get(), utf16Units, bidiDir);
1703 if (!bidi) {
1704 SkDEBUGF("Bidi error\n");
1705 return nullptr;
1706 }
1707
1708 return std::make_unique<SkUnicodeBidiRunIterator>(utf8, utf8 + utf8Bytes, std::move(bidi));
1709 }
1710
1711 std::unique_ptr<SkShaper::ScriptRunIterator>
1712 SkShaper::MakeHbIcuScriptRunIterator(const char* utf8, size_t utf8Bytes) {
1713 return SkShaper::MakeSkUnicodeHbScriptRunIterator(utf8, utf8Bytes);
1714 }
1715
1716 std::unique_ptr<SkShaper::ScriptRunIterator>
1717 SkShaper::MakeSkUnicodeHbScriptRunIterator(const char* utf8, size_t utf8Bytes) {
1718 return std::make_unique<SkUnicodeHbScriptRunIterator>(utf8, utf8Bytes, HB_SCRIPT_UNKNOWN);
1719 }
1720
1721 std::unique_ptr<SkShaper::ScriptRunIterator> SkShaper::MakeSkUnicodeHbScriptRunIterator(
1722 const char* utf8, size_t utf8Bytes, SkFourByteTag script) {
1723 return std::make_unique<SkUnicodeHbScriptRunIterator>(
1724 utf8, utf8Bytes, hb_script_from_iso15924_tag((hb_tag_t)script));
1725 }
1726
1727 #ifndef USE_SKIA_TXT
1728 std::unique_ptr<SkShaper> SkShaper::MakeShaperDrivenWrapper(sk_sp<SkFontMgr> fontmgr) {
1729 return MakeHarfBuzz(std::move(fontmgr), true);
1730 }
1731 std::unique_ptr<SkShaper> SkShaper::MakeShapeThenWrap(sk_sp<SkFontMgr> fontmgr) {
1732 return MakeHarfBuzz(std::move(fontmgr), false);
1733 }
1734 #else
1735 std::unique_ptr<SkShaper> SkShaper::MakeShaperDrivenWrapper(std::shared_ptr<RSFontMgr> fontmgr) {
1736 return MakeHarfBuzz(std::move(fontmgr), true);
1737 }
1738 std::unique_ptr<SkShaper> SkShaper::MakeShapeThenWrap(std::shared_ptr<RSFontMgr> fontmgr) {
1739 return MakeHarfBuzz(std::move(fontmgr), false);
1740 }
1741 #endif
1742 #ifndef USE_SKIA_TXT
1743 std::unique_ptr<SkShaper> SkShaper::MakeShapeDontWrapOrReorder(std::unique_ptr<SkUnicode> unicode,
1744 sk_sp<SkFontMgr> fontmgr) {
1745 #else
1746 std::unique_ptr<SkShaper> SkShaper::MakeShapeDontWrapOrReorder(std::unique_ptr<SkUnicode> unicode,
1747 std::shared_ptr<RSFontMgr> fontmgr) {
1748 #endif
1749 HBBuffer buffer(hb_buffer_create());
1750 if (!buffer) {
1751 SkDEBUGF("Could not create hb_buffer");
1752 return nullptr;
1753 }
1754
1755 if (!unicode) {
1756 return nullptr;
1757 }
1758
1759 return std::make_unique<ShapeDontWrapOrReorder>
1760 (std::move(unicode), nullptr, nullptr, std::move(buffer), std::move(fontmgr));
1761 }
1762
1763 void SkShaper::PurgeHarfBuzzCache() {
1764 HBLockedFaceCache cache = get_hbFace_cache();
1765 cache.reset();
1766 }
1767 #ifdef USE_SKIA_TXT
1768 } // namespace SkiaRsText
1769 #endif