1/*
2 * Copyright © 2010,2011,2012  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#ifndef HB_OT_SHAPE_COMPLEX_PRIVATE_HH
28#define HB_OT_SHAPE_COMPLEX_PRIVATE_HH
29
30#include "hb-private.hh"
31
32#include "hb-ot-shape-private.hh"
33#include "hb-ot-shape-normalize-private.hh"
34
35
36
37/* buffer var allocations, used by complex shapers */
38#define complex_var_u8_0()	var2.u8[2]
39#define complex_var_u8_1()	var2.u8[3]
40
41
42#define HB_OT_SHAPE_COMPLEX_MAX_COMBINING_MARKS 32
43
44enum hb_ot_shape_zero_width_marks_type_t {
45  HB_OT_SHAPE_ZERO_WIDTH_MARKS_NONE,
46  HB_OT_SHAPE_ZERO_WIDTH_MARKS_BY_GDEF_EARLY,
47  HB_OT_SHAPE_ZERO_WIDTH_MARKS_BY_GDEF_LATE
48};
49
50
51/* Master OT shaper list */
52#define HB_COMPLEX_SHAPERS_IMPLEMENT_SHAPERS \
53  HB_COMPLEX_SHAPER_IMPLEMENT (default) /* should be first */ \
54  HB_COMPLEX_SHAPER_IMPLEMENT (arabic) \
55  HB_COMPLEX_SHAPER_IMPLEMENT (hangul) \
56  HB_COMPLEX_SHAPER_IMPLEMENT (hebrew) \
57  HB_COMPLEX_SHAPER_IMPLEMENT (myanmar_old) \
58  HB_COMPLEX_SHAPER_IMPLEMENT (indic) \
59  HB_COMPLEX_SHAPER_IMPLEMENT (myanmar) \
60  HB_COMPLEX_SHAPER_IMPLEMENT (thai) \
61  HB_COMPLEX_SHAPER_IMPLEMENT (tibetan) \
62  HB_COMPLEX_SHAPER_IMPLEMENT (use) \
63  /* ^--- Add new shapers here */
64
65
66struct hb_ot_complex_shaper_t
67{
68  /* collect_features()
69   * Called during shape_plan().
70   * Shapers should use plan->map to add their features and callbacks.
71   * May be nullptr.
72   */
73  void (*collect_features) (hb_ot_shape_planner_t *plan);
74
75  /* override_features()
76   * Called during shape_plan().
77   * Shapers should use plan->map to override features and add callbacks after
78   * common features are added.
79   * May be nullptr.
80   */
81  void (*override_features) (hb_ot_shape_planner_t *plan);
82
83
84  /* data_create()
85   * Called at the end of shape_plan().
86   * Whatever shapers return will be accessible through plan->data later.
87   * If nullptr is returned, means a plan failure.
88   */
89  void *(*data_create) (const hb_ot_shape_plan_t *plan);
90
91  /* data_destroy()
92   * Called when the shape_plan is being destroyed.
93   * plan->data is passed here for destruction.
94   * If nullptr is returned, means a plan failure.
95   * May be nullptr.
96   */
97  void (*data_destroy) (void *data);
98
99
100  /* preprocess_text()
101   * Called during shape().
102   * Shapers can use to modify text before shaping starts.
103   * May be nullptr.
104   */
105  void (*preprocess_text) (const hb_ot_shape_plan_t *plan,
106			   hb_buffer_t              *buffer,
107			   hb_font_t                *font);
108
109  /* postprocess_glyphs()
110   * Called during shape().
111   * Shapers can use to modify glyphs after shaping ends.
112   * May be nullptr.
113   */
114  void (*postprocess_glyphs) (const hb_ot_shape_plan_t *plan,
115			      hb_buffer_t              *buffer,
116			      hb_font_t                *font);
117
118
119  hb_ot_shape_normalization_mode_t normalization_preference;
120
121  /* decompose()
122   * Called during shape()'s normalization.
123   * May be nullptr.
124   */
125  bool (*decompose) (const hb_ot_shape_normalize_context_t *c,
126		     hb_codepoint_t  ab,
127		     hb_codepoint_t *a,
128		     hb_codepoint_t *b);
129
130  /* compose()
131   * Called during shape()'s normalization.
132   * May be nullptr.
133   */
134  bool (*compose) (const hb_ot_shape_normalize_context_t *c,
135		   hb_codepoint_t  a,
136		   hb_codepoint_t  b,
137		   hb_codepoint_t *ab);
138
139  /* setup_masks()
140   * Called during shape().
141   * Shapers should use map to get feature masks and set on buffer.
142   * Shapers may NOT modify characters.
143   * May be nullptr.
144   */
145  void (*setup_masks) (const hb_ot_shape_plan_t *plan,
146		       hb_buffer_t              *buffer,
147		       hb_font_t                *font);
148
149  /* disable_otl()
150   * Called during shape().
151   * If set and returns true, GDEF/GSUB/GPOS of the font are ignored
152   * and fallback operations used.
153   * May be nullptr.
154   */
155  bool (*disable_otl) (const hb_ot_shape_plan_t *plan);
156
157  /* reorder_marks()
158   * Called during shape().
159   * Shapers can use to modify ordering of combining marks.
160   * May be nullptr.
161   */
162  void (*reorder_marks) (const hb_ot_shape_plan_t *plan,
163			 hb_buffer_t              *buffer,
164			 unsigned int              start,
165			 unsigned int              end);
166
167  hb_ot_shape_zero_width_marks_type_t zero_width_marks;
168
169  bool fallback_position;
170};
171
172#define HB_COMPLEX_SHAPER_IMPLEMENT(name) extern HB_INTERNAL const hb_ot_complex_shaper_t _hb_ot_complex_shaper_##name;
173HB_COMPLEX_SHAPERS_IMPLEMENT_SHAPERS
174#undef HB_COMPLEX_SHAPER_IMPLEMENT
175
176
177static inline const hb_ot_complex_shaper_t *
178hb_ot_shape_complex_categorize (const hb_ot_shape_planner_t *planner)
179{
180  switch ((hb_tag_t) planner->props.script)
181  {
182    default:
183      return &_hb_ot_complex_shaper_default;
184
185
186    /* Unicode-1.1 additions */
187    case HB_SCRIPT_ARABIC:
188
189    /* Unicode-3.0 additions */
190    case HB_SCRIPT_MONGOLIAN:
191    case HB_SCRIPT_SYRIAC:
192
193    /* Unicode-5.0 additions */
194    case HB_SCRIPT_NKO:
195    case HB_SCRIPT_PHAGS_PA:
196
197    /* Unicode-6.0 additions */
198    case HB_SCRIPT_MANDAIC:
199
200    /* Unicode-7.0 additions */
201    case HB_SCRIPT_MANICHAEAN:
202    case HB_SCRIPT_PSALTER_PAHLAVI:
203
204    /* Unicode-9.0 additions */
205    case HB_SCRIPT_ADLAM:
206
207      /* For Arabic script, use the Arabic shaper even if no OT script tag was found.
208       * This is because we do fallback shaping for Arabic script (and not others).
209       * But note that Arabic shaping is applicable only to horizontal layout; for
210       * vertical text, just use the generic shaper instead. */
211      if ((planner->map.chosen_script[0] != HB_OT_TAG_DEFAULT_SCRIPT ||
212	   planner->props.script == HB_SCRIPT_ARABIC) &&
213	  HB_DIRECTION_IS_HORIZONTAL(planner->props.direction))
214	return &_hb_ot_complex_shaper_arabic;
215      else
216	return &_hb_ot_complex_shaper_default;
217
218
219    /* Unicode-1.1 additions */
220    case HB_SCRIPT_THAI:
221    case HB_SCRIPT_LAO:
222
223      return &_hb_ot_complex_shaper_thai;
224
225
226    /* Unicode-1.1 additions */
227    case HB_SCRIPT_HANGUL:
228
229      return &_hb_ot_complex_shaper_hangul;
230
231
232    /* Unicode-2.0 additions */
233    case HB_SCRIPT_TIBETAN:
234
235      return &_hb_ot_complex_shaper_tibetan;
236
237
238    /* Unicode-1.1 additions */
239    case HB_SCRIPT_HEBREW:
240
241      return &_hb_ot_complex_shaper_hebrew;
242
243
244    /* ^--- Add new shapers here */
245
246#if 0
247    /* Unicode-4.1 additions */
248    case HB_SCRIPT_NEW_TAI_LUE:
249#endif
250
251    /* Unicode-1.1 additions */
252    case HB_SCRIPT_BENGALI:
253    case HB_SCRIPT_DEVANAGARI:
254    case HB_SCRIPT_GUJARATI:
255    case HB_SCRIPT_GURMUKHI:
256    case HB_SCRIPT_KANNADA:
257    case HB_SCRIPT_MALAYALAM:
258    case HB_SCRIPT_ORIYA:
259    case HB_SCRIPT_TAMIL:
260    case HB_SCRIPT_TELUGU:
261
262    /* Unicode-3.0 additions */
263    case HB_SCRIPT_SINHALA:
264
265      /* If the designer designed the font for the 'DFLT' script,
266       * (or we ended up arbitrarily pick 'latn'), use the default shaper.
267       * Otherwise, use the specific shaper.
268       * Note that for some simple scripts, there may not be *any*
269       * GSUB/GPOS needed, so there may be no scripts found! */
270      if (planner->map.chosen_script[0] == HB_TAG ('D','F','L','T') ||
271	  planner->map.chosen_script[0] == HB_TAG ('l','a','t','n'))
272	return &_hb_ot_complex_shaper_default;
273      else
274	return &_hb_ot_complex_shaper_indic;
275
276    case HB_SCRIPT_KHMER:
277      /* A number of Khmer fonts in the wild don't have a 'pref' feature,
278       * and as such won't shape properly via the Indic shaper;
279       * however, they typically have 'liga' / 'clig' features that implement
280       * the necessary "reordering" by means of ligature substitutions.
281       * So we send such pref-less fonts through the generic shaper instead. */
282      if (planner->map.found_script[0] &&
283	  hb_ot_layout_language_find_feature (planner->face, HB_OT_TAG_GSUB,
284					      planner->map.script_index[0],
285					      planner->map.language_index[0],
286					      HB_TAG ('p','r','e','f'),
287					      nullptr))
288	return &_hb_ot_complex_shaper_indic;
289      else
290	return &_hb_ot_complex_shaper_default;
291
292    case HB_SCRIPT_MYANMAR:
293      if (planner->map.chosen_script[0] == HB_TAG ('m','y','m','2'))
294	return &_hb_ot_complex_shaper_myanmar;
295      else if (planner->map.chosen_script[0] == HB_TAG ('m','y','m','r'))
296	return &_hb_ot_complex_shaper_myanmar_old;
297      else
298	return &_hb_ot_complex_shaper_default;
299
300
301    /* Unicode-2.0 additions */
302    //case HB_SCRIPT_TIBETAN:
303
304    /* Unicode-3.0 additions */
305    //case HB_SCRIPT_MONGOLIAN:
306    //case HB_SCRIPT_SINHALA:
307
308    /* Unicode-3.2 additions */
309    case HB_SCRIPT_BUHID:
310    case HB_SCRIPT_HANUNOO:
311    case HB_SCRIPT_TAGALOG:
312    case HB_SCRIPT_TAGBANWA:
313
314    /* Unicode-4.0 additions */
315    case HB_SCRIPT_LIMBU:
316    case HB_SCRIPT_TAI_LE:
317
318    /* Unicode-4.1 additions */
319    case HB_SCRIPT_BUGINESE:
320    case HB_SCRIPT_KHAROSHTHI:
321    case HB_SCRIPT_SYLOTI_NAGRI:
322    case HB_SCRIPT_TIFINAGH:
323
324    /* Unicode-5.0 additions */
325    case HB_SCRIPT_BALINESE:
326    //case HB_SCRIPT_NKO:
327    //case HB_SCRIPT_PHAGS_PA:
328
329    /* Unicode-5.1 additions */
330    case HB_SCRIPT_CHAM:
331    case HB_SCRIPT_KAYAH_LI:
332    case HB_SCRIPT_LEPCHA:
333    case HB_SCRIPT_REJANG:
334    case HB_SCRIPT_SAURASHTRA:
335    case HB_SCRIPT_SUNDANESE:
336
337    /* Unicode-5.2 additions */
338    case HB_SCRIPT_EGYPTIAN_HIEROGLYPHS:
339    case HB_SCRIPT_JAVANESE:
340    case HB_SCRIPT_KAITHI:
341    case HB_SCRIPT_MEETEI_MAYEK:
342    case HB_SCRIPT_TAI_THAM:
343    case HB_SCRIPT_TAI_VIET:
344
345    /* Unicode-6.0 additions */
346    case HB_SCRIPT_BATAK:
347    case HB_SCRIPT_BRAHMI:
348    //case HB_SCRIPT_MANDAIC:
349
350    /* Unicode-6.1 additions */
351    case HB_SCRIPT_CHAKMA:
352    case HB_SCRIPT_SHARADA:
353    case HB_SCRIPT_TAKRI:
354
355    /* Unicode-7.0 additions */
356    case HB_SCRIPT_DUPLOYAN:
357    case HB_SCRIPT_GRANTHA:
358    case HB_SCRIPT_KHOJKI:
359    case HB_SCRIPT_KHUDAWADI:
360    case HB_SCRIPT_MAHAJANI:
361    //case HB_SCRIPT_MANICHAEAN:
362    case HB_SCRIPT_MODI:
363    case HB_SCRIPT_PAHAWH_HMONG:
364    //case HB_SCRIPT_PSALTER_PAHLAVI:
365    case HB_SCRIPT_SIDDHAM:
366    case HB_SCRIPT_TIRHUTA:
367
368    /* Unicode-8.0 additions */
369    case HB_SCRIPT_AHOM:
370    //case HB_SCRIPT_MULTANI:
371
372    /* Unicode-9.0 additions */
373    case HB_SCRIPT_BHAIKSUKI:
374    case HB_SCRIPT_MARCHEN:
375    case HB_SCRIPT_NEWA:
376
377    /* Unicode-10.0 additions */
378    case HB_SCRIPT_MASARAM_GONDI:
379    case HB_SCRIPT_SOYOMBO:
380    case HB_SCRIPT_ZANABAZAR_SQUARE:
381
382      /* If the designer designed the font for the 'DFLT' script,
383       * (or we ended up arbitrarily pick 'latn'), use the default shaper.
384       * Otherwise, use the specific shaper.
385       * Note that for some simple scripts, there may not be *any*
386       * GSUB/GPOS needed, so there may be no scripts found! */
387      if (planner->map.chosen_script[0] == HB_TAG ('D','F','L','T') ||
388	  planner->map.chosen_script[0] == HB_TAG ('l','a','t','n'))
389	return &_hb_ot_complex_shaper_default;
390      else
391	return &_hb_ot_complex_shaper_use;
392  }
393}
394
395
396#endif /* HB_OT_SHAPE_COMPLEX_PRIVATE_HH */
397