Line data Source code
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 :
38 : static const hb_tag_t
39 : basic_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 : };
50 : static const hb_tag_t
51 : other_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 :
75 : static void
76 : setup_syllables (const hb_ot_shape_plan_t *plan,
77 : hb_font_t *font,
78 : hb_buffer_t *buffer);
79 : static void
80 : initial_reordering (const hb_ot_shape_plan_t *plan,
81 : hb_font_t *font,
82 : hb_buffer_t *buffer);
83 : static void
84 : final_reordering (const hb_ot_shape_plan_t *plan,
85 : hb_font_t *font,
86 : hb_buffer_t *buffer);
87 :
88 : static void
89 0 : collect_features_myanmar (hb_ot_shape_planner_t *plan)
90 : {
91 0 : hb_ot_map_builder_t *map = &plan->map;
92 :
93 : /* Do this before any lookups have been applied. */
94 0 : map->add_gsub_pause (setup_syllables);
95 :
96 0 : 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 0 : map->add_global_bool_feature (HB_TAG('c','c','m','p'));
100 :
101 :
102 0 : map->add_gsub_pause (initial_reordering);
103 0 : for (unsigned int i = 0; i < ARRAY_LENGTH (basic_features); i++)
104 : {
105 0 : map->add_feature (basic_features[i], 1, F_GLOBAL | F_MANUAL_ZWJ);
106 0 : map->add_gsub_pause (NULL);
107 : }
108 0 : map->add_gsub_pause (final_reordering);
109 0 : for (unsigned int i = 0; i < ARRAY_LENGTH (other_features); i++)
110 0 : map->add_feature (other_features[i], 1, F_GLOBAL | F_MANUAL_ZWJ);
111 0 : }
112 :
113 : static void
114 0 : override_features_myanmar (hb_ot_shape_planner_t *plan)
115 : {
116 0 : plan->map.add_feature (HB_TAG('l','i','g','a'), 0, F_GLOBAL);
117 0 : }
118 :
119 :
120 : enum 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. */
132 : enum myanmar_category_t {
133 : OT_As = 18, /* Asat */
134 : OT_D = 19, /* Digits except zero */
135 : OT_D0 = 20, /* Digit zero */
136 : OT_DB = OT_N, /* Dot below */
137 : OT_GB = OT_PLACEHOLDER,
138 : OT_MH = 21, /* Various consonant medial types */
139 : OT_MR = 22, /* Various consonant medial types */
140 : OT_MW = 23, /* Various consonant medial types */
141 : OT_MY = 24, /* Various consonant medial types */
142 : OT_PT = 25, /* Pwo and other tones */
143 : OT_VAbv = 26,
144 : OT_VBlw = 27,
145 : OT_VPre = 28,
146 : OT_VPst = 29,
147 : OT_VS = 30, /* Variation selectors */
148 : OT_P = 31 /* Punctuation */
149 : };
150 :
151 :
152 : static inline bool
153 0 : is_one_of (const hb_glyph_info_t &info, unsigned int flags)
154 : {
155 : /* If it ligated, all bets are off. */
156 0 : if (_hb_glyph_info_ligated (&info)) return false;
157 0 : return !!(FLAG_SAFE (info.myanmar_category()) & flags);
158 : }
159 :
160 : static inline bool
161 0 : is_consonant (const hb_glyph_info_t &info)
162 : {
163 0 : return is_one_of (info, CONSONANT_FLAGS);
164 : }
165 :
166 :
167 : static inline void
168 0 : set_myanmar_properties (hb_glyph_info_t &info)
169 : {
170 0 : hb_codepoint_t u = info.codepoint;
171 0 : unsigned int type = hb_indic_get_categories (u);
172 0 : indic_category_t cat = (indic_category_t) (type & 0x7Fu);
173 0 : 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 0 : if (unlikely (hb_in_range (u, 0xFE00u, 0xFE0Fu)))
179 0 : cat = (indic_category_t) OT_VS;
180 :
181 0 : switch (u)
182 : {
183 : case 0x104Eu:
184 0 : cat = (indic_category_t) OT_C; /* The spec says C, IndicSyllableCategory doesn't have. */
185 0 : 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 0 : cat = (indic_category_t) OT_GB;
192 0 : break;
193 :
194 : case 0x1004u: case 0x101Bu: case 0x105Au:
195 0 : cat = (indic_category_t) OT_Ra;
196 0 : break;
197 :
198 : case 0x1032u: case 0x1036u:
199 0 : cat = (indic_category_t) OT_A;
200 0 : break;
201 :
202 : case 0x1039u:
203 0 : cat = (indic_category_t) OT_H;
204 0 : break;
205 :
206 : case 0x103Au:
207 0 : cat = (indic_category_t) OT_As;
208 0 : 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 0 : cat = (indic_category_t) OT_D;
216 0 : break;
217 :
218 : case 0x1040u:
219 0 : cat = (indic_category_t) OT_D; /* XXX The spec says D0, but Uniscribe doesn't seem to do. */
220 0 : break;
221 :
222 : case 0x103Eu: case 0x1060u:
223 0 : cat = (indic_category_t) OT_MH;
224 0 : break;
225 :
226 : case 0x103Cu:
227 0 : cat = (indic_category_t) OT_MR;
228 0 : break;
229 :
230 : case 0x103Du: case 0x1082u:
231 0 : cat = (indic_category_t) OT_MW;
232 0 : break;
233 :
234 : case 0x103Bu: case 0x105Eu: case 0x105Fu:
235 0 : cat = (indic_category_t) OT_MY;
236 0 : break;
237 :
238 : case 0x1063u: case 0x1064u: case 0x1069u: case 0x106Au:
239 : case 0x106Bu: case 0x106Cu: case 0x106Du: case 0xAA7Bu:
240 0 : cat = (indic_category_t) OT_PT;
241 0 : 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 0 : cat = (indic_category_t) OT_SM;
247 0 : break;
248 :
249 : case 0x104Au: case 0x104Bu:
250 0 : cat = (indic_category_t) OT_P;
251 0 : break;
252 :
253 : case 0xAA74u: case 0xAA75u: case 0xAA76u:
254 : /* https://github.com/roozbehp/unicode-data/issues/3 */
255 0 : cat = (indic_category_t) OT_C;
256 0 : break;
257 : }
258 :
259 0 : if (cat == OT_M)
260 : {
261 0 : switch ((int) pos)
262 : {
263 0 : case POS_PRE_C: cat = (indic_category_t) OT_VPre;
264 0 : pos = POS_PRE_M; break;
265 0 : case POS_ABOVE_C: cat = (indic_category_t) OT_VAbv; break;
266 0 : case POS_BELOW_C: cat = (indic_category_t) OT_VBlw; break;
267 0 : case POS_POST_C: cat = (indic_category_t) OT_VPst; break;
268 : }
269 : }
270 :
271 0 : info.myanmar_category() = (myanmar_category_t) cat;
272 0 : info.myanmar_position() = pos;
273 0 : }
274 :
275 :
276 :
277 : static void
278 0 : setup_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 0 : HB_BUFFER_ALLOCATE_VAR (buffer, myanmar_category);
283 0 : 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 0 : unsigned int count = buffer->len;
289 0 : hb_glyph_info_t *info = buffer->info;
290 0 : for (unsigned int i = 0; i < count; i++)
291 0 : set_myanmar_properties (info[i]);
292 0 : }
293 :
294 : static void
295 0 : setup_syllables (const hb_ot_shape_plan_t *plan HB_UNUSED,
296 : hb_font_t *font HB_UNUSED,
297 : hb_buffer_t *buffer)
298 : {
299 0 : find_syllables (buffer);
300 0 : }
301 :
302 : static int
303 0 : compare_myanmar_order (const hb_glyph_info_t *pa, const hb_glyph_info_t *pb)
304 : {
305 0 : int a = pa->myanmar_position();
306 0 : int b = pb->myanmar_position();
307 :
308 0 : return a < b ? -1 : a == b ? 0 : +1;
309 : }
310 :
311 :
312 : /* Rules from:
313 : * http://www.microsoft.com/typography/OpenTypeDev/myanmar/intro.htm */
314 :
315 : static void
316 0 : initial_reordering_consonant_syllable (hb_buffer_t *buffer,
317 : unsigned int start, unsigned int end)
318 : {
319 0 : hb_glyph_info_t *info = buffer->info;
320 :
321 0 : unsigned int base = end;
322 0 : bool has_reph = false;
323 :
324 : {
325 0 : unsigned int limit = start;
326 0 : if (start + 3 <= end &&
327 0 : info[start ].myanmar_category() == OT_Ra &&
328 0 : info[start+1].myanmar_category() == OT_As &&
329 0 : info[start+2].myanmar_category() == OT_H)
330 : {
331 0 : limit += 3;
332 0 : base = start;
333 0 : has_reph = true;
334 : }
335 :
336 : {
337 0 : if (!has_reph)
338 0 : base = limit;
339 :
340 0 : for (unsigned int i = limit; i < end; i++)
341 0 : if (is_consonant (info[i]))
342 : {
343 0 : base = i;
344 0 : break;
345 : }
346 : }
347 : }
348 :
349 : /* Reorder! */
350 : {
351 0 : unsigned int i = start;
352 0 : for (; i < start + (has_reph ? 3 : 0); i++)
353 0 : info[i].myanmar_position() = POS_AFTER_MAIN;
354 0 : for (; i < base; i++)
355 0 : info[i].myanmar_position() = POS_PRE_C;
356 0 : if (i < end)
357 : {
358 0 : info[i].myanmar_position() = POS_BASE_C;
359 0 : i++;
360 : }
361 0 : indic_position_t pos = POS_AFTER_MAIN;
362 : /* The following loop may be ugly, but it implements all of
363 : * Myanmar reordering! */
364 0 : for (; i < end; i++)
365 : {
366 0 : if (info[i].myanmar_category() == OT_MR) /* Pre-base reordering */
367 : {
368 0 : info[i].myanmar_position() = POS_PRE_C;
369 0 : continue;
370 : }
371 0 : if (info[i].myanmar_position() < POS_BASE_C) /* Left matra */
372 : {
373 0 : continue;
374 : }
375 :
376 0 : if (pos == POS_AFTER_MAIN && info[i].myanmar_category() == OT_VBlw)
377 : {
378 0 : pos = POS_BELOW_C;
379 0 : info[i].myanmar_position() = pos;
380 0 : continue;
381 : }
382 :
383 0 : if (pos == POS_BELOW_C && info[i].myanmar_category() == OT_A)
384 : {
385 0 : info[i].myanmar_position() = POS_BEFORE_SUB;
386 0 : continue;
387 : }
388 0 : if (pos == POS_BELOW_C && info[i].myanmar_category() == OT_VBlw)
389 : {
390 0 : info[i].myanmar_position() = pos;
391 0 : continue;
392 : }
393 0 : if (pos == POS_BELOW_C && info[i].myanmar_category() != OT_A)
394 : {
395 0 : pos = POS_AFTER_SUB;
396 0 : info[i].myanmar_position() = pos;
397 0 : continue;
398 : }
399 0 : info[i].myanmar_position() = pos;
400 : }
401 : }
402 :
403 : /* Sit tight, rock 'n roll! */
404 0 : buffer->sort (start, end, compare_myanmar_order);
405 0 : }
406 :
407 : static void
408 0 : initial_reordering_syllable (const hb_ot_shape_plan_t *plan,
409 : hb_face_t *face,
410 : hb_buffer_t *buffer,
411 : unsigned int start, unsigned int end)
412 : {
413 0 : syllable_type_t syllable_type = (syllable_type_t) (buffer->info[start].syllable() & 0x0F);
414 0 : switch (syllable_type) {
415 :
416 : case broken_cluster: /* We already inserted dotted-circles, so just call the consonant_syllable. */
417 : case consonant_syllable:
418 0 : initial_reordering_consonant_syllable (buffer, start, end);
419 0 : break;
420 :
421 : case punctuation_cluster:
422 : case non_myanmar_cluster:
423 0 : break;
424 : }
425 0 : }
426 :
427 : static inline void
428 0 : insert_dotted_circles (const hb_ot_shape_plan_t *plan HB_UNUSED,
429 : hb_font_t *font,
430 : hb_buffer_t *buffer)
431 : {
432 : /* Note: This loop is extra overhead, but should not be measurable. */
433 0 : bool has_broken_syllables = false;
434 0 : unsigned int count = buffer->len;
435 0 : hb_glyph_info_t *info = buffer->info;
436 0 : for (unsigned int i = 0; i < count; i++)
437 0 : if ((info[i].syllable() & 0x0F) == broken_cluster)
438 : {
439 0 : has_broken_syllables = true;
440 0 : break;
441 : }
442 0 : if (likely (!has_broken_syllables))
443 0 : return;
444 :
445 :
446 : hb_codepoint_t dottedcircle_glyph;
447 0 : if (!font->get_nominal_glyph (0x25CCu, &dottedcircle_glyph))
448 0 : return;
449 :
450 0 : hb_glyph_info_t dottedcircle = {0};
451 0 : dottedcircle.codepoint = 0x25CCu;
452 0 : set_myanmar_properties (dottedcircle);
453 0 : dottedcircle.codepoint = dottedcircle_glyph;
454 :
455 0 : buffer->clear_output ();
456 :
457 0 : buffer->idx = 0;
458 0 : unsigned int last_syllable = 0;
459 0 : while (buffer->idx < buffer->len && !buffer->in_error)
460 : {
461 0 : unsigned int syllable = buffer->cur().syllable();
462 0 : syllable_type_t syllable_type = (syllable_type_t) (syllable & 0x0F);
463 0 : if (unlikely (last_syllable != syllable && syllable_type == broken_cluster))
464 : {
465 0 : last_syllable = syllable;
466 :
467 0 : hb_glyph_info_t ginfo = dottedcircle;
468 0 : ginfo.cluster = buffer->cur().cluster;
469 0 : ginfo.mask = buffer->cur().mask;
470 0 : ginfo.syllable() = buffer->cur().syllable();
471 :
472 0 : buffer->output_info (ginfo);
473 : }
474 : else
475 0 : buffer->next_glyph ();
476 : }
477 :
478 0 : buffer->swap_buffers ();
479 : }
480 :
481 : static void
482 0 : initial_reordering (const hb_ot_shape_plan_t *plan,
483 : hb_font_t *font,
484 : hb_buffer_t *buffer)
485 : {
486 0 : insert_dotted_circles (plan, font, buffer);
487 :
488 0 : foreach_syllable (buffer, start, end)
489 0 : initial_reordering_syllable (plan, font->face, buffer, start, end);
490 0 : }
491 :
492 : static void
493 0 : final_reordering (const hb_ot_shape_plan_t *plan,
494 : hb_font_t *font HB_UNUSED,
495 : hb_buffer_t *buffer)
496 : {
497 0 : hb_glyph_info_t *info = buffer->info;
498 0 : unsigned int count = buffer->len;
499 :
500 : /* Zero syllables now... */
501 0 : for (unsigned int i = 0; i < count; i++)
502 0 : info[i].syllable() = 0;
503 :
504 0 : HB_BUFFER_DEALLOCATE_VAR (buffer, myanmar_category);
505 0 : HB_BUFFER_DEALLOCATE_VAR (buffer, myanmar_position);
506 0 : }
507 :
508 :
509 : /* Uniscribe seems to have a shaper for 'mymr' that is like the
510 : * generic shaper, except that it zeros mark advances GDEF_LATE. */
511 : const hb_ot_complex_shaper_t _hb_ot_complex_shaper_myanmar_old =
512 : {
513 : "default",
514 : NULL, /* collect_features */
515 : NULL, /* override_features */
516 : NULL, /* data_create */
517 : NULL, /* data_destroy */
518 : NULL, /* preprocess_text */
519 : NULL, /* postprocess_glyphs */
520 : HB_OT_SHAPE_NORMALIZATION_MODE_DEFAULT,
521 : NULL, /* decompose */
522 : NULL, /* compose */
523 : NULL, /* setup_masks */
524 : NULL, /* disable_otl */
525 : HB_OT_SHAPE_ZERO_WIDTH_MARKS_BY_GDEF_LATE,
526 : true, /* fallback_position */
527 : };
528 :
529 : const hb_ot_complex_shaper_t _hb_ot_complex_shaper_myanmar =
530 : {
531 : "myanmar",
532 : collect_features_myanmar,
533 : override_features_myanmar,
534 : NULL, /* data_create */
535 : NULL, /* data_destroy */
536 : NULL, /* preprocess_text */
537 : NULL, /* postprocess_glyphs */
538 : HB_OT_SHAPE_NORMALIZATION_MODE_COMPOSED_DIACRITICS_NO_SHORT_CIRCUIT,
539 : NULL, /* decompose */
540 : NULL, /* compose */
541 : setup_masks_myanmar,
542 : NULL, /* disable_otl */
543 : HB_OT_SHAPE_ZERO_WIDTH_MARKS_BY_GDEF_EARLY,
544 : false, /* fallback_position */
545 : };
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