1/*
2 * Copyright © 2011,2012,2013 Google, Inc.
3 *
4 * This is part of HarfBuzz, a text shaping library.
5 *
6 * Permission is hereby granted, without written agreement and without
7 * license or royalty fees, to use, copy, modify, and distribute this
8 * software and its documentation for any purpose, provided that the
9 * above copyright notice and the following two paragraphs appear in
10 * all copies of this software.
11 *
12 * IN NO EVENT SHALL THE COPYRIGHT HOLDER BE LIABLE TO ANY PARTY FOR
13 * DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES
14 * ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN
15 * IF THE COPYRIGHT HOLDER HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH
16 * DAMAGE.
17 *
18 * THE COPYRIGHT HOLDER SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING,
19 * BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
20 * FITNESS FOR A PARTICULAR PURPOSE. THE SOFTWARE PROVIDED HEREUNDER IS
21 * ON AN "AS IS" BASIS, AND THE COPYRIGHT HOLDER HAS NO OBLIGATION TO
22 * PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.
23 *
24 * Google Author(s): Behdad Esfahbod
25 */
26
27#include "hb-ot-shape-complex-indic-private.hh"
28
29/* buffer var allocations */
30#define myanmar_category() complex_var_u8_0() /* myanmar_category_t */
31#define myanmar_position() complex_var_u8_1() /* myanmar_position_t */
32
33
34/*
35 * Myanmar shaper.
36 */
37
38static const hb_tag_t
39basic_features[] =
40{
41 /*
42 * Basic features.
43 * These features are applied in order, one at a time, after initial_reordering.
44 */
45 HB_TAG('r','p','h','f'),
46 HB_TAG('p','r','e','f'),
47 HB_TAG('b','l','w','f'),
48 HB_TAG('p','s','t','f'),
49};
50static const hb_tag_t
51other_features[] =
52{
53 /*
54 * Other features.
55 * These features are applied all at once, after final_reordering.
56 */
57 HB_TAG('p','r','e','s'),
58 HB_TAG('a','b','v','s'),
59 HB_TAG('b','l','w','s'),
60 HB_TAG('p','s','t','s'),
61 /* Positioning features, though we don't care about the types. */
62 HB_TAG('d','i','s','t'),
63 /* Pre-release version of Windows 8 Myanmar font had abvm,blwm
64 * features. The released Windows 8 version of the font (as well
65 * as the released spec) used 'mark' instead. The Windows 8
66 * shaper however didn't apply 'mark' but did apply 'mkmk'.
67 * Perhaps it applied abvm/blwm. This was fixed in a Windows 8
68 * update, so now it applies mark/mkmk. We are guessing that
69 * it still applies abvm/blwm too.
70 */
71 HB_TAG('a','b','v','m'),
72 HB_TAG('b','l','w','m'),
73};
74
75static void
76setup_syllables (const hb_ot_shape_plan_t *plan,
77 hb_font_t *font,
78 hb_buffer_t *buffer);
79static void
80initial_reordering (const hb_ot_shape_plan_t *plan,
81 hb_font_t *font,
82 hb_buffer_t *buffer);
83static void
84final_reordering (const hb_ot_shape_plan_t *plan,
85 hb_font_t *font,
86 hb_buffer_t *buffer);
87
88static void
89collect_features_myanmar (hb_ot_shape_planner_t *plan)
90{
91 hb_ot_map_builder_t *map = &plan->map;
92
93 /* Do this before any lookups have been applied. */
94 map->add_gsub_pause (pause_func: setup_syllables);
95
96 map->add_global_bool_feature (HB_TAG('l','o','c','l'));
97 /* The Indic specs do not require ccmp, but we apply it here since if
98 * there is a use of it, it's typically at the beginning. */
99 map->add_global_bool_feature (HB_TAG('c','c','m','p'));
100
101
102 map->add_gsub_pause (pause_func: initial_reordering);
103 for (unsigned int i = 0; i < ARRAY_LENGTH (basic_features); i++)
104 {
105 map->add_feature (tag: basic_features[i], value: 1, flags: F_GLOBAL | F_MANUAL_ZWJ);
106 map->add_gsub_pause (pause_func: nullptr);
107 }
108 map->add_gsub_pause (pause_func: final_reordering);
109 for (unsigned int i = 0; i < ARRAY_LENGTH (other_features); i++)
110 map->add_feature (tag: other_features[i], value: 1, flags: F_GLOBAL | F_MANUAL_ZWJ);
111}
112
113static void
114override_features_myanmar (hb_ot_shape_planner_t *plan)
115{
116 plan->map.add_feature (HB_TAG('l','i','g','a'), value: 0, flags: F_GLOBAL);
117}
118
119
120enum syllable_type_t {
121 consonant_syllable,
122 punctuation_cluster,
123 broken_cluster,
124 non_myanmar_cluster,
125};
126
127#include "hb-ot-shape-complex-myanmar-machine.hh"
128
129
130/* Note: This enum is duplicated in the -machine.rl source file.
131 * Not sure how to avoid duplication. */
132enum myanmar_category_t {
133 OT_As = 18, /* Asat */
134 OT_D0 = 20, /* Digit zero */
135 OT_DB = OT_N, /* Dot below */
136 OT_GB = OT_PLACEHOLDER,
137 OT_MH = 21, /* Various consonant medial types */
138 OT_MR = 22, /* Various consonant medial types */
139 OT_MW = 23, /* Various consonant medial types */
140 OT_MY = 24, /* Various consonant medial types */
141 OT_PT = 25, /* Pwo and other tones */
142 OT_VAbv = 26,
143 OT_VBlw = 27,
144 OT_VPre = 28,
145 OT_VPst = 29,
146 OT_VS = 30, /* Variation selectors */
147 OT_P = 31, /* Punctuation */
148 OT_D = 32, /* Digits except zero */
149};
150
151
152static inline bool
153is_one_of (const hb_glyph_info_t &info, unsigned int flags)
154{
155 /* If it ligated, all bets are off. */
156 if (_hb_glyph_info_ligated (info: &info)) return false;
157 return !!(FLAG_UNSAFE (info.myanmar_category()) & flags);
158}
159
160static inline bool
161is_consonant (const hb_glyph_info_t &info)
162{
163 return is_one_of (info, CONSONANT_FLAGS);
164}
165
166
167static inline void
168set_myanmar_properties (hb_glyph_info_t &info)
169{
170 hb_codepoint_t u = info.codepoint;
171 unsigned int type = hb_indic_get_categories (u);
172 indic_category_t cat = (indic_category_t) (type & 0x7Fu);
173 indic_position_t pos = (indic_position_t) (type >> 8);
174
175 /* Myanmar
176 * http://www.microsoft.com/typography/OpenTypeDev/myanmar/intro.htm#analyze
177 */
178 if (unlikely (hb_in_range<hb_codepoint_t> (u, 0xFE00u, 0xFE0Fu)))
179 cat = (indic_category_t) OT_VS;
180
181 switch (u)
182 {
183 case 0x104Eu:
184 cat = (indic_category_t) OT_C; /* The spec says C, IndicSyllableCategory doesn't have. */
185 break;
186
187 case 0x002Du: case 0x00A0u: case 0x00D7u: case 0x2012u:
188 case 0x2013u: case 0x2014u: case 0x2015u: case 0x2022u:
189 case 0x25CCu: case 0x25FBu: case 0x25FCu: case 0x25FDu:
190 case 0x25FEu:
191 cat = (indic_category_t) OT_GB;
192 break;
193
194 case 0x1004u: case 0x101Bu: case 0x105Au:
195 cat = (indic_category_t) OT_Ra;
196 break;
197
198 case 0x1032u: case 0x1036u:
199 cat = (indic_category_t) OT_A;
200 break;
201
202 case 0x1039u:
203 cat = (indic_category_t) OT_H;
204 break;
205
206 case 0x103Au:
207 cat = (indic_category_t) OT_As;
208 break;
209
210 case 0x1041u: case 0x1042u: case 0x1043u: case 0x1044u:
211 case 0x1045u: case 0x1046u: case 0x1047u: case 0x1048u:
212 case 0x1049u: case 0x1090u: case 0x1091u: case 0x1092u:
213 case 0x1093u: case 0x1094u: case 0x1095u: case 0x1096u:
214 case 0x1097u: case 0x1098u: case 0x1099u:
215 cat = (indic_category_t) OT_D;
216 break;
217
218 case 0x1040u:
219 cat = (indic_category_t) OT_D; /* XXX The spec says D0, but Uniscribe doesn't seem to do. */
220 break;
221
222 case 0x103Eu: case 0x1060u:
223 cat = (indic_category_t) OT_MH;
224 break;
225
226 case 0x103Cu:
227 cat = (indic_category_t) OT_MR;
228 break;
229
230 case 0x103Du: case 0x1082u:
231 cat = (indic_category_t) OT_MW;
232 break;
233
234 case 0x103Bu: case 0x105Eu: case 0x105Fu:
235 cat = (indic_category_t) OT_MY;
236 break;
237
238 case 0x1063u: case 0x1064u: case 0x1069u: case 0x106Au:
239 case 0x106Bu: case 0x106Cu: case 0x106Du: case 0xAA7Bu:
240 cat = (indic_category_t) OT_PT;
241 break;
242
243 case 0x1038u: case 0x1087u: case 0x1088u: case 0x1089u:
244 case 0x108Au: case 0x108Bu: case 0x108Cu: case 0x108Du:
245 case 0x108Fu: case 0x109Au: case 0x109Bu: case 0x109Cu:
246 cat = (indic_category_t) OT_SM;
247 break;
248
249 case 0x104Au: case 0x104Bu:
250 cat = (indic_category_t) OT_P;
251 break;
252
253 case 0xAA74u: case 0xAA75u: case 0xAA76u:
254 /* https://github.com/roozbehp/unicode-data/issues/3 */
255 cat = (indic_category_t) OT_C;
256 break;
257 }
258
259 if (cat == OT_M)
260 {
261 switch ((int) pos)
262 {
263 case POS_PRE_C: cat = (indic_category_t) OT_VPre;
264 pos = POS_PRE_M; break;
265 case POS_ABOVE_C: cat = (indic_category_t) OT_VAbv; break;
266 case POS_BELOW_C: cat = (indic_category_t) OT_VBlw; break;
267 case POS_POST_C: cat = (indic_category_t) OT_VPst; break;
268 }
269 }
270
271 info.myanmar_category() = (myanmar_category_t) cat;
272 info.myanmar_position() = pos;
273}
274
275
276
277static void
278setup_masks_myanmar (const hb_ot_shape_plan_t *plan HB_UNUSED,
279 hb_buffer_t *buffer,
280 hb_font_t *font HB_UNUSED)
281{
282 HB_BUFFER_ALLOCATE_VAR (buffer, myanmar_category);
283 HB_BUFFER_ALLOCATE_VAR (buffer, myanmar_position);
284
285 /* We cannot setup masks here. We save information about characters
286 * and setup masks later on in a pause-callback. */
287
288 unsigned int count = buffer->len;
289 hb_glyph_info_t *info = buffer->info;
290 for (unsigned int i = 0; i < count; i++)
291 set_myanmar_properties (info[i]);
292}
293
294static void
295setup_syllables (const hb_ot_shape_plan_t *plan HB_UNUSED,
296 hb_font_t *font HB_UNUSED,
297 hb_buffer_t *buffer)
298{
299 find_syllables (buffer);
300 foreach_syllable (buffer, start, end)
301 buffer->unsafe_to_break (start, end);
302}
303
304static int
305compare_myanmar_order (const hb_glyph_info_t *pa, const hb_glyph_info_t *pb)
306{
307 int a = pa->myanmar_position();
308 int b = pb->myanmar_position();
309
310 return a < b ? -1 : a == b ? 0 : +1;
311}
312
313
314/* Rules from:
315 * http://www.microsoft.com/typography/OpenTypeDev/myanmar/intro.htm */
316
317static void
318initial_reordering_consonant_syllable (hb_buffer_t *buffer,
319 unsigned int start, unsigned int end)
320{
321 hb_glyph_info_t *info = buffer->info;
322
323 unsigned int base = end;
324 bool has_reph = false;
325
326 {
327 unsigned int limit = start;
328 if (start + 3 <= end &&
329 info[start ].myanmar_category() == OT_Ra &&
330 info[start+1].myanmar_category() == OT_As &&
331 info[start+2].myanmar_category() == OT_H)
332 {
333 limit += 3;
334 base = start;
335 has_reph = true;
336 }
337
338 {
339 if (!has_reph)
340 base = limit;
341
342 for (unsigned int i = limit; i < end; i++)
343 if (is_consonant (info: info[i]))
344 {
345 base = i;
346 break;
347 }
348 }
349 }
350
351 /* Reorder! */
352 {
353 unsigned int i = start;
354 for (; i < start + (has_reph ? 3 : 0); i++)
355 info[i].myanmar_position() = POS_AFTER_MAIN;
356 for (; i < base; i++)
357 info[i].myanmar_position() = POS_PRE_C;
358 if (i < end)
359 {
360 info[i].myanmar_position() = POS_BASE_C;
361 i++;
362 }
363 indic_position_t pos = POS_AFTER_MAIN;
364 /* The following loop may be ugly, but it implements all of
365 * Myanmar reordering! */
366 for (; i < end; i++)
367 {
368 if (info[i].myanmar_category() == OT_MR) /* Pre-base reordering */
369 {
370 info[i].myanmar_position() = POS_PRE_C;
371 continue;
372 }
373 if (info[i].myanmar_position() < POS_BASE_C) /* Left matra */
374 {
375 continue;
376 }
377
378 if (pos == POS_AFTER_MAIN && info[i].myanmar_category() == OT_VBlw)
379 {
380 pos = POS_BELOW_C;
381 info[i].myanmar_position() = pos;
382 continue;
383 }
384
385 if (pos == POS_BELOW_C && info[i].myanmar_category() == OT_A)
386 {
387 info[i].myanmar_position() = POS_BEFORE_SUB;
388 continue;
389 }
390 if (pos == POS_BELOW_C && info[i].myanmar_category() == OT_VBlw)
391 {
392 info[i].myanmar_position() = pos;
393 continue;
394 }
395 if (pos == POS_BELOW_C && info[i].myanmar_category() != OT_A)
396 {
397 pos = POS_AFTER_SUB;
398 info[i].myanmar_position() = pos;
399 continue;
400 }
401 info[i].myanmar_position() = pos;
402 }
403 }
404
405 /* Sit tight, rock 'n roll! */
406 buffer->sort (start, end, compar: compare_myanmar_order);
407}
408
409static void
410initial_reordering_syllable (const hb_ot_shape_plan_t *plan,
411 hb_face_t *face,
412 hb_buffer_t *buffer,
413 unsigned int start, unsigned int end)
414{
415 syllable_type_t syllable_type = (syllable_type_t) (buffer->info[start].syllable() & 0x0F);
416 switch (syllable_type) {
417
418 case broken_cluster: /* We already inserted dotted-circles, so just call the consonant_syllable. */
419 case consonant_syllable:
420 initial_reordering_consonant_syllable (buffer, start, end);
421 break;
422
423 case punctuation_cluster:
424 case non_myanmar_cluster:
425 break;
426 }
427}
428
429static inline void
430insert_dotted_circles (const hb_ot_shape_plan_t *plan HB_UNUSED,
431 hb_font_t *font,
432 hb_buffer_t *buffer)
433{
434 /* Note: This loop is extra overhead, but should not be measurable. */
435 bool has_broken_syllables = false;
436 unsigned int count = buffer->len;
437 hb_glyph_info_t *info = buffer->info;
438 for (unsigned int i = 0; i < count; i++)
439 if ((info[i].syllable() & 0x0F) == broken_cluster)
440 {
441 has_broken_syllables = true;
442 break;
443 }
444 if (likely (!has_broken_syllables))
445 return;
446
447
448 hb_codepoint_t dottedcircle_glyph;
449 if (!font->get_nominal_glyph (unicode: 0x25CCu, glyph: &dottedcircle_glyph))
450 return;
451
452 hb_glyph_info_t dottedcircle = {.codepoint: 0};
453 dottedcircle.codepoint = 0x25CCu;
454 set_myanmar_properties (dottedcircle);
455 dottedcircle.codepoint = dottedcircle_glyph;
456
457 buffer->clear_output ();
458
459 buffer->idx = 0;
460 unsigned int last_syllable = 0;
461 while (buffer->idx < buffer->len && !buffer->in_error)
462 {
463 unsigned int syllable = buffer->cur().syllable();
464 syllable_type_t syllable_type = (syllable_type_t) (syllable & 0x0F);
465 if (unlikely (last_syllable != syllable && syllable_type == broken_cluster))
466 {
467 last_syllable = syllable;
468
469 hb_glyph_info_t ginfo = dottedcircle;
470 ginfo.cluster = buffer->cur().cluster;
471 ginfo.mask = buffer->cur().mask;
472 ginfo.syllable() = buffer->cur().syllable();
473
474 buffer->output_info (glyph_info: ginfo);
475 }
476 else
477 buffer->next_glyph ();
478 }
479
480 buffer->swap_buffers ();
481}
482
483static void
484initial_reordering (const hb_ot_shape_plan_t *plan,
485 hb_font_t *font,
486 hb_buffer_t *buffer)
487{
488 insert_dotted_circles (plan, font, buffer);
489
490 foreach_syllable (buffer, start, end)
491 initial_reordering_syllable (plan, face: font->face, buffer, start, end);
492}
493
494static void
495final_reordering (const hb_ot_shape_plan_t *plan,
496 hb_font_t *font HB_UNUSED,
497 hb_buffer_t *buffer)
498{
499 hb_glyph_info_t *info = buffer->info;
500 unsigned int count = buffer->len;
501
502 /* Zero syllables now... */
503 for (unsigned int i = 0; i < count; i++)
504 info[i].syllable() = 0;
505
506 HB_BUFFER_DEALLOCATE_VAR (buffer, myanmar_category);
507 HB_BUFFER_DEALLOCATE_VAR (buffer, myanmar_position);
508}
509
510
511/* Uniscribe seems to have a shaper for 'mymr' that is like the
512 * generic shaper, except that it zeros mark advances GDEF_LATE. */
513const hb_ot_complex_shaper_t _hb_ot_complex_shaper_myanmar_old =
514{
515 .collect_features: nullptr, /* collect_features */
516 .override_features: nullptr, /* override_features */
517 .data_create: nullptr, /* data_create */
518 .data_destroy: nullptr, /* data_destroy */
519 .preprocess_text: nullptr, /* preprocess_text */
520 .postprocess_glyphs: nullptr, /* postprocess_glyphs */
521 .normalization_preference: HB_OT_SHAPE_NORMALIZATION_MODE_DEFAULT,
522 .decompose: nullptr, /* decompose */
523 .compose: nullptr, /* compose */
524 .setup_masks: nullptr, /* setup_masks */
525 .disable_otl: nullptr, /* disable_otl */
526 .reorder_marks: nullptr, /* reorder_marks */
527 .zero_width_marks: HB_OT_SHAPE_ZERO_WIDTH_MARKS_BY_GDEF_LATE,
528 .fallback_position: true, /* fallback_position */
529};
530
531const hb_ot_complex_shaper_t _hb_ot_complex_shaper_myanmar =
532{
533 .collect_features: collect_features_myanmar,
534 .override_features: override_features_myanmar,
535 .data_create: nullptr, /* data_create */
536 .data_destroy: nullptr, /* data_destroy */
537 .preprocess_text: nullptr, /* preprocess_text */
538 .postprocess_glyphs: nullptr, /* postprocess_glyphs */
539 .normalization_preference: HB_OT_SHAPE_NORMALIZATION_MODE_COMPOSED_DIACRITICS_NO_SHORT_CIRCUIT,
540 .decompose: nullptr, /* decompose */
541 .compose: nullptr, /* compose */
542 .setup_masks: setup_masks_myanmar,
543 .disable_otl: nullptr, /* disable_otl */
544 .reorder_marks: nullptr, /* reorder_marks */
545 .zero_width_marks: HB_OT_SHAPE_ZERO_WIDTH_MARKS_BY_GDEF_EARLY,
546 .fallback_position: false, /* fallback_position */
547};
548

source code of qtbase/src/3rdparty/harfbuzz-ng/src/hb-ot-shape-complex-myanmar.cc