hb-ot-layout.h
17.4 KB
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
/*
* Copyright © 2007,2008,2009 Red Hat, Inc.
*
* This is part of HarfBuzz, a text shaping library.
*
* Permission is hereby granted, without written agreement and without
* license or royalty fees, to use, copy, modify, and distribute this
* software and its documentation for any purpose, provided that the
* above copyright notice and the following two paragraphs appear in
* all copies of this software.
*
* IN NO EVENT SHALL THE COPYRIGHT HOLDER BE LIABLE TO ANY PARTY FOR
* DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES
* ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN
* IF THE COPYRIGHT HOLDER HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH
* DAMAGE.
*
* THE COPYRIGHT HOLDER SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING,
* BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
* FITNESS FOR A PARTICULAR PURPOSE. THE SOFTWARE PROVIDED HEREUNDER IS
* ON AN "AS IS" BASIS, AND THE COPYRIGHT HOLDER HAS NO OBLIGATION TO
* PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.
*
* Red Hat Author(s): Behdad Esfahbod
*/
#if !defined(HB_OT_H_IN) && !defined(HB_NO_SINGLE_HEADER_ERROR)
#error "Include <hb-ot.h> instead."
#endif
#ifndef HB_OT_LAYOUT_H
#define HB_OT_LAYOUT_H
#include "hb.h"
#include "hb-ot-name.h"
HB_BEGIN_DECLS
/**
* HB_OT_TAG_BASE:
*
* OpenType [Baseline Table](https://docs.microsoft.com/en-us/typography/opentype/spec/base).
*/
#define HB_OT_TAG_BASE HB_TAG('B','A','S','E')
/**
* HB_OT_TAG_GDEF:
*
* OpenType [Glyph Definition Table](https://docs.microsoft.com/en-us/typography/opentype/spec/gdef).
*/
#define HB_OT_TAG_GDEF HB_TAG('G','D','E','F')
/**
* HB_OT_TAG_GSUB:
*
* OpenType [Glyph Substitution Table](https://docs.microsoft.com/en-us/typography/opentype/spec/gsub).
*/
#define HB_OT_TAG_GSUB HB_TAG('G','S','U','B')
/**
* HB_OT_TAG_GPOS:
*
* OpenType [Glyph Positioning Table](https://docs.microsoft.com/en-us/typography/opentype/spec/gpos).
*/
#define HB_OT_TAG_GPOS HB_TAG('G','P','O','S')
/**
* HB_OT_TAG_JSTF:
*
* OpenType [Justification Table](https://docs.microsoft.com/en-us/typography/opentype/spec/jstf).
*/
#define HB_OT_TAG_JSTF HB_TAG('J','S','T','F')
/*
* Script & Language tags.
*/
/**
* HB_OT_TAG_DEFAULT_SCRIPT:
*
* OpenType script tag, `DFLT`, for features that are not script-specific.
*
*/
#define HB_OT_TAG_DEFAULT_SCRIPT HB_TAG ('D', 'F', 'L', 'T')
/**
* HB_OT_TAG_DEFAULT_LANGUAGE:
*
* OpenType language tag, `dflt`. Not a valid language tag, but some fonts
* mistakenly use it.
*/
#define HB_OT_TAG_DEFAULT_LANGUAGE HB_TAG ('d', 'f', 'l', 't')
/**
* HB_OT_MAX_TAGS_PER_SCRIPT:
*
* Maximum number of OpenType tags that can correspond to a give #hb_script_t.
*
* Since: 2.0.0
**/
#define HB_OT_MAX_TAGS_PER_SCRIPT 3u
/**
* HB_OT_MAX_TAGS_PER_LANGUAGE:
*
* Maximum number of OpenType tags that can correspond to a give #hb_language_t.
*
* Since: 2.0.0
**/
#define HB_OT_MAX_TAGS_PER_LANGUAGE 3u
HB_EXTERN void
hb_ot_tags_from_script_and_language (hb_script_t script,
hb_language_t language,
unsigned int *script_count /* IN/OUT */,
hb_tag_t *script_tags /* OUT */,
unsigned int *language_count /* IN/OUT */,
hb_tag_t *language_tags /* OUT */);
HB_EXTERN hb_script_t
hb_ot_tag_to_script (hb_tag_t tag);
HB_EXTERN hb_language_t
hb_ot_tag_to_language (hb_tag_t tag);
HB_EXTERN void
hb_ot_tags_to_script_and_language (hb_tag_t script_tag,
hb_tag_t language_tag,
hb_script_t *script /* OUT */,
hb_language_t *language /* OUT */);
/*
* GDEF
*/
HB_EXTERN hb_bool_t
hb_ot_layout_has_glyph_classes (hb_face_t *face);
/**
* hb_ot_layout_glyph_class_t:
* @HB_OT_LAYOUT_GLYPH_CLASS_UNCLASSIFIED: Glyphs not matching the other classifications
* @HB_OT_LAYOUT_GLYPH_CLASS_BASE_GLYPH: Spacing, single characters, capable of accepting marks
* @HB_OT_LAYOUT_GLYPH_CLASS_LIGATURE: Glyphs that represent ligation of multiple characters
* @HB_OT_LAYOUT_GLYPH_CLASS_MARK: Non-spacing, combining glyphs that represent marks
* @HB_OT_LAYOUT_GLYPH_CLASS_COMPONENT: Spacing glyphs that represent part of a single character
*
* The GDEF classes defined for glyphs.
*
**/
typedef enum {
HB_OT_LAYOUT_GLYPH_CLASS_UNCLASSIFIED = 0,
HB_OT_LAYOUT_GLYPH_CLASS_BASE_GLYPH = 1,
HB_OT_LAYOUT_GLYPH_CLASS_LIGATURE = 2,
HB_OT_LAYOUT_GLYPH_CLASS_MARK = 3,
HB_OT_LAYOUT_GLYPH_CLASS_COMPONENT = 4
} hb_ot_layout_glyph_class_t;
HB_EXTERN hb_ot_layout_glyph_class_t
hb_ot_layout_get_glyph_class (hb_face_t *face,
hb_codepoint_t glyph);
HB_EXTERN void
hb_ot_layout_get_glyphs_in_class (hb_face_t *face,
hb_ot_layout_glyph_class_t klass,
hb_set_t *glyphs /* OUT */);
/* Not that useful. Provides list of attach points for a glyph that a
* client may want to cache */
HB_EXTERN unsigned int
hb_ot_layout_get_attach_points (hb_face_t *face,
hb_codepoint_t glyph,
unsigned int start_offset,
unsigned int *point_count /* IN/OUT */,
unsigned int *point_array /* OUT */);
/* Ligature caret positions */
HB_EXTERN unsigned int
hb_ot_layout_get_ligature_carets (hb_font_t *font,
hb_direction_t direction,
hb_codepoint_t glyph,
unsigned int start_offset,
unsigned int *caret_count /* IN/OUT */,
hb_position_t *caret_array /* OUT */);
/*
* GSUB/GPOS feature query and enumeration interface
*/
/**
* HB_OT_LAYOUT_NO_SCRIPT_INDEX:
*
* Special value for script index indicating unsupported script.
*/
#define HB_OT_LAYOUT_NO_SCRIPT_INDEX 0xFFFFu
/**
* HB_OT_LAYOUT_NO_FEATURE_INDEX:
*
* Special value for feature index indicating unsupported feature.
*/
#define HB_OT_LAYOUT_NO_FEATURE_INDEX 0xFFFFu
/**
* HB_OT_LAYOUT_DEFAULT_LANGUAGE_INDEX:
*
* Special value for language index indicating default or unsupported language.
*/
#define HB_OT_LAYOUT_DEFAULT_LANGUAGE_INDEX 0xFFFFu
/**
* HB_OT_LAYOUT_NO_VARIATIONS_INDEX:
*
* Special value for variations index indicating unsupported variation.
*/
#define HB_OT_LAYOUT_NO_VARIATIONS_INDEX 0xFFFFFFFFu
HB_EXTERN unsigned int
hb_ot_layout_table_get_script_tags (hb_face_t *face,
hb_tag_t table_tag,
unsigned int start_offset,
unsigned int *script_count /* IN/OUT */,
hb_tag_t *script_tags /* OUT */);
HB_EXTERN hb_bool_t
hb_ot_layout_table_find_script (hb_face_t *face,
hb_tag_t table_tag,
hb_tag_t script_tag,
unsigned int *script_index /* OUT */);
HB_EXTERN hb_bool_t
hb_ot_layout_table_select_script (hb_face_t *face,
hb_tag_t table_tag,
unsigned int script_count,
const hb_tag_t *script_tags,
unsigned int *script_index /* OUT */,
hb_tag_t *chosen_script /* OUT */);
HB_EXTERN unsigned int
hb_ot_layout_table_get_feature_tags (hb_face_t *face,
hb_tag_t table_tag,
unsigned int start_offset,
unsigned int *feature_count /* IN/OUT */,
hb_tag_t *feature_tags /* OUT */);
HB_EXTERN unsigned int
hb_ot_layout_script_get_language_tags (hb_face_t *face,
hb_tag_t table_tag,
unsigned int script_index,
unsigned int start_offset,
unsigned int *language_count /* IN/OUT */,
hb_tag_t *language_tags /* OUT */);
HB_EXTERN hb_bool_t
hb_ot_layout_script_select_language (hb_face_t *face,
hb_tag_t table_tag,
unsigned int script_index,
unsigned int language_count,
const hb_tag_t *language_tags,
unsigned int *language_index /* OUT */);
HB_EXTERN hb_bool_t
hb_ot_layout_language_get_required_feature_index (hb_face_t *face,
hb_tag_t table_tag,
unsigned int script_index,
unsigned int language_index,
unsigned int *feature_index /* OUT */);
HB_EXTERN hb_bool_t
hb_ot_layout_language_get_required_feature (hb_face_t *face,
hb_tag_t table_tag,
unsigned int script_index,
unsigned int language_index,
unsigned int *feature_index /* OUT */,
hb_tag_t *feature_tag /* OUT */);
HB_EXTERN unsigned int
hb_ot_layout_language_get_feature_indexes (hb_face_t *face,
hb_tag_t table_tag,
unsigned int script_index,
unsigned int language_index,
unsigned int start_offset,
unsigned int *feature_count /* IN/OUT */,
unsigned int *feature_indexes /* OUT */);
HB_EXTERN unsigned int
hb_ot_layout_language_get_feature_tags (hb_face_t *face,
hb_tag_t table_tag,
unsigned int script_index,
unsigned int language_index,
unsigned int start_offset,
unsigned int *feature_count /* IN/OUT */,
hb_tag_t *feature_tags /* OUT */);
HB_EXTERN hb_bool_t
hb_ot_layout_language_find_feature (hb_face_t *face,
hb_tag_t table_tag,
unsigned int script_index,
unsigned int language_index,
hb_tag_t feature_tag,
unsigned int *feature_index /* OUT */);
HB_EXTERN unsigned int
hb_ot_layout_feature_get_lookups (hb_face_t *face,
hb_tag_t table_tag,
unsigned int feature_index,
unsigned int start_offset,
unsigned int *lookup_count /* IN/OUT */,
unsigned int *lookup_indexes /* OUT */);
HB_EXTERN unsigned int
hb_ot_layout_table_get_lookup_count (hb_face_t *face,
hb_tag_t table_tag);
HB_EXTERN void
hb_ot_layout_collect_features (hb_face_t *face,
hb_tag_t table_tag,
const hb_tag_t *scripts,
const hb_tag_t *languages,
const hb_tag_t *features,
hb_set_t *feature_indexes /* OUT */);
HB_EXTERN void
hb_ot_layout_collect_lookups (hb_face_t *face,
hb_tag_t table_tag,
const hb_tag_t *scripts,
const hb_tag_t *languages,
const hb_tag_t *features,
hb_set_t *lookup_indexes /* OUT */);
HB_EXTERN void
hb_ot_layout_lookup_collect_glyphs (hb_face_t *face,
hb_tag_t table_tag,
unsigned int lookup_index,
hb_set_t *glyphs_before, /* OUT. May be NULL */
hb_set_t *glyphs_input, /* OUT. May be NULL */
hb_set_t *glyphs_after, /* OUT. May be NULL */
hb_set_t *glyphs_output /* OUT. May be NULL */);
#ifdef HB_NOT_IMPLEMENTED
typedef struct
{
const hb_codepoint_t *before,
unsigned int before_length,
const hb_codepoint_t *input,
unsigned int input_length,
const hb_codepoint_t *after,
unsigned int after_length,
} hb_ot_layout_glyph_sequence_t;
typedef hb_bool_t
(*hb_ot_layout_glyph_sequence_func_t) (hb_font_t *font,
hb_tag_t table_tag,
unsigned int lookup_index,
const hb_ot_layout_glyph_sequence_t *sequence,
void *user_data);
HB_EXTERN void
Xhb_ot_layout_lookup_enumerate_sequences (hb_face_t *face,
hb_tag_t table_tag,
unsigned int lookup_index,
hb_ot_layout_glyph_sequence_func_t callback,
void *user_data);
#endif
/* Variations support */
HB_EXTERN hb_bool_t
hb_ot_layout_table_find_feature_variations (hb_face_t *face,
hb_tag_t table_tag,
const int *coords,
unsigned int num_coords,
unsigned int *variations_index /* out */);
HB_EXTERN unsigned int
hb_ot_layout_feature_with_variations_get_lookups (hb_face_t *face,
hb_tag_t table_tag,
unsigned int feature_index,
unsigned int variations_index,
unsigned int start_offset,
unsigned int *lookup_count /* IN/OUT */,
unsigned int *lookup_indexes /* OUT */);
/*
* GSUB
*/
HB_EXTERN hb_bool_t
hb_ot_layout_has_substitution (hb_face_t *face);
HB_EXTERN unsigned
hb_ot_layout_lookup_get_glyph_alternates (hb_face_t *face,
unsigned lookup_index,
hb_codepoint_t glyph,
unsigned start_offset,
unsigned *alternate_count /* IN/OUT */,
hb_codepoint_t *alternate_glyphs /* OUT */);
HB_EXTERN hb_bool_t
hb_ot_layout_lookup_would_substitute (hb_face_t *face,
unsigned int lookup_index,
const hb_codepoint_t *glyphs,
unsigned int glyphs_length,
hb_bool_t zero_context);
HB_EXTERN void
hb_ot_layout_lookup_substitute_closure (hb_face_t *face,
unsigned int lookup_index,
hb_set_t *glyphs
/*TODO , hb_bool_t inclusive */);
HB_EXTERN void
hb_ot_layout_lookups_substitute_closure (hb_face_t *face,
const hb_set_t *lookups,
hb_set_t *glyphs);
#ifdef HB_NOT_IMPLEMENTED
/* Note: You better have GDEF when using this API, or marks won't do much. */
HB_EXTERN hb_bool_t
Xhb_ot_layout_lookup_substitute (hb_font_t *font,
unsigned int lookup_index,
const hb_ot_layout_glyph_sequence_t *sequence,
unsigned int out_size,
hb_codepoint_t *glyphs_out, /* OUT */
unsigned int *clusters_out, /* OUT */
unsigned int *out_length /* OUT */);
#endif
/*
* GPOS
*/
HB_EXTERN hb_bool_t
hb_ot_layout_has_positioning (hb_face_t *face);
#ifdef HB_NOT_IMPLEMENTED
/* Note: You better have GDEF when using this API, or marks won't do much. */
HB_EXTERN hb_bool_t
Xhb_ot_layout_lookup_position (hb_font_t *font,
unsigned int lookup_index,
const hb_ot_layout_glyph_sequence_t *sequence,
hb_glyph_position_t *positions /* IN / OUT */);
#endif
/* Optical 'size' feature info. Returns true if found.
* https://docs.microsoft.com/en-us/typography/opentype/spec/features_pt#size */
HB_EXTERN hb_bool_t
hb_ot_layout_get_size_params (hb_face_t *face,
unsigned int *design_size, /* OUT. May be NULL */
unsigned int *subfamily_id, /* OUT. May be NULL */
hb_ot_name_id_t *subfamily_name_id, /* OUT. May be NULL */
unsigned int *range_start, /* OUT. May be NULL */
unsigned int *range_end /* OUT. May be NULL */);
HB_EXTERN hb_bool_t
hb_ot_layout_feature_get_name_ids (hb_face_t *face,
hb_tag_t table_tag,
unsigned int feature_index,
hb_ot_name_id_t *label_id /* OUT. May be NULL */,
hb_ot_name_id_t *tooltip_id /* OUT. May be NULL */,
hb_ot_name_id_t *sample_id /* OUT. May be NULL */,
unsigned int *num_named_parameters /* OUT. May be NULL */,
hb_ot_name_id_t *first_param_id /* OUT. May be NULL */);
HB_EXTERN unsigned int
hb_ot_layout_feature_get_characters (hb_face_t *face,
hb_tag_t table_tag,
unsigned int feature_index,
unsigned int start_offset,
unsigned int *char_count /* IN/OUT. May be NULL */,
hb_codepoint_t *characters /* OUT. May be NULL */);
/*
* BASE
*/
/**
* hb_ot_layout_baseline_tag_t:
* @HB_OT_LAYOUT_BASELINE_TAG_ROMAN: The baseline used by alphabetic scripts such as Latin, Cyrillic and Greek.
* In vertical writing mode, the alphabetic baseline for characters rotated 90 degrees clockwise.
* (This would not apply to alphabetic characters that remain upright in vertical writing mode, since these
* characters are not rotated.)
* @HB_OT_LAYOUT_BASELINE_TAG_HANGING: The hanging baseline. In horizontal direction, this is the horizontal
* line from which syllables seem, to hang in Tibetan and other similar scripts. In vertical writing mode,
* for Tibetan (or some other similar script) characters rotated 90 degrees clockwise.
* @HB_OT_LAYOUT_BASELINE_TAG_IDEO_FACE_BOTTOM_OR_LEFT: Ideographic character face bottom or left edge,
* if the direction is horizontal or vertical, respectively.
* @HB_OT_LAYOUT_BASELINE_TAG_IDEO_FACE_TOP_OR_RIGHT: Ideographic character face top or right edge,
* if the direction is horizontal or vertical, respectively.
* @HB_OT_LAYOUT_BASELINE_TAG_IDEO_EMBOX_BOTTOM_OR_LEFT: Ideographic em-box bottom or left edge,
* if the direction is horizontal or vertical, respectively.
* @HB_OT_LAYOUT_BASELINE_TAG_IDEO_EMBOX_TOP_OR_RIGHT: Ideographic em-box top or right edge baseline,
* if the direction is horizontal or vertical, respectively.
* @HB_OT_LAYOUT_BASELINE_TAG_MATH: The baseline about which mathematical characters are centered.
* In vertical writing mode when mathematical characters rotated 90 degrees clockwise, are centered.
*
* Baseline tags from [Baseline Tags](https://docs.microsoft.com/en-us/typography/opentype/spec/baselinetags) registry.
*
* Since: 2.6.0
*/
typedef enum {
HB_OT_LAYOUT_BASELINE_TAG_ROMAN = HB_TAG ('r','o','m','n'),
HB_OT_LAYOUT_BASELINE_TAG_HANGING = HB_TAG ('h','a','n','g'),
HB_OT_LAYOUT_BASELINE_TAG_IDEO_FACE_BOTTOM_OR_LEFT = HB_TAG ('i','c','f','b'),
HB_OT_LAYOUT_BASELINE_TAG_IDEO_FACE_TOP_OR_RIGHT = HB_TAG ('i','c','f','t'),
HB_OT_LAYOUT_BASELINE_TAG_IDEO_EMBOX_BOTTOM_OR_LEFT = HB_TAG ('i','d','e','o'),
HB_OT_LAYOUT_BASELINE_TAG_IDEO_EMBOX_TOP_OR_RIGHT = HB_TAG ('i','d','t','p'),
HB_OT_LAYOUT_BASELINE_TAG_MATH = HB_TAG ('m','a','t','h'),
/*< private >*/
_HB_OT_LAYOUT_BASELINE_TAG_MAX_VALUE = HB_TAG_MAX_SIGNED /*< skip >*/
} hb_ot_layout_baseline_tag_t;
HB_EXTERN hb_bool_t
hb_ot_layout_get_baseline (hb_font_t *font,
hb_ot_layout_baseline_tag_t baseline_tag,
hb_direction_t direction,
hb_tag_t script_tag,
hb_tag_t language_tag,
hb_position_t *coord /* OUT. May be NULL. */);
HB_END_DECLS
#endif /* HB_OT_LAYOUT_H */