1/*
2 * Copyright © 2007,2008,2009 Red Hat, 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 * Red Hat Author(s): Behdad Esfahbod
25 */
26
27#if !defined(HB_OT_H_IN) && !defined(HB_NO_SINGLE_HEADER_ERROR)
28#error "Include <hb-ot.h> instead."
29#endif
30
31#ifndef HB_OT_LAYOUT_H
32#define HB_OT_LAYOUT_H
33
34#include "hb.h"
35
36#include "hb-ot-name.h"
37
38HB_BEGIN_DECLS
39
40
41/**
42 * HB_OT_TAG_BASE:
43 *
44 * OpenType [Baseline Table](https://docs.microsoft.com/en-us/typography/opentype/spec/base).
45 */
46#define HB_OT_TAG_BASE HB_TAG('B','A','S','E')
47/**
48 * HB_OT_TAG_GDEF:
49 *
50 * OpenType [Glyph Definition Table](https://docs.microsoft.com/en-us/typography/opentype/spec/gdef).
51 */
52#define HB_OT_TAG_GDEF HB_TAG('G','D','E','F')
53/**
54 * HB_OT_TAG_GSUB:
55 *
56 * OpenType [Glyph Substitution Table](https://docs.microsoft.com/en-us/typography/opentype/spec/gsub).
57 */
58#define HB_OT_TAG_GSUB HB_TAG('G','S','U','B')
59/**
60 * HB_OT_TAG_GPOS:
61 *
62 * OpenType [Glyph Positioning Table](https://docs.microsoft.com/en-us/typography/opentype/spec/gpos).
63 */
64#define HB_OT_TAG_GPOS HB_TAG('G','P','O','S')
65/**
66 * HB_OT_TAG_JSTF:
67 *
68 * OpenType [Justification Table](https://docs.microsoft.com/en-us/typography/opentype/spec/jstf).
69 */
70#define HB_OT_TAG_JSTF HB_TAG('J','S','T','F')
71
72
73/*
74 * Script & Language tags.
75 */
76
77/**
78 * HB_OT_TAG_DEFAULT_SCRIPT:
79 *
80 * OpenType script tag, `DFLT`, for features that are not script-specific.
81 *
82 */
83#define HB_OT_TAG_DEFAULT_SCRIPT HB_TAG ('D', 'F', 'L', 'T')
84/**
85 * HB_OT_TAG_DEFAULT_LANGUAGE:
86 *
87 * OpenType language tag, `dflt`. Not a valid language tag, but some fonts
88 * mistakenly use it.
89 */
90#define HB_OT_TAG_DEFAULT_LANGUAGE HB_TAG ('d', 'f', 'l', 't')
91
92/**
93 * HB_OT_MAX_TAGS_PER_SCRIPT:
94 *
95 * Maximum number of OpenType tags that can correspond to a give #hb_script_t.
96 *
97 * Since: 2.0.0
98 **/
99#define HB_OT_MAX_TAGS_PER_SCRIPT 3u
100/**
101 * HB_OT_MAX_TAGS_PER_LANGUAGE:
102 *
103 * Maximum number of OpenType tags that can correspond to a give #hb_language_t.
104 *
105 * Since: 2.0.0
106 **/
107#define HB_OT_MAX_TAGS_PER_LANGUAGE 3u
108
109HB_EXTERN void
110hb_ot_tags_from_script_and_language (hb_script_t script,
111 hb_language_t language,
112 unsigned int *script_count /* IN/OUT */,
113 hb_tag_t *script_tags /* OUT */,
114 unsigned int *language_count /* IN/OUT */,
115 hb_tag_t *language_tags /* OUT */);
116
117HB_EXTERN hb_script_t
118hb_ot_tag_to_script (hb_tag_t tag);
119
120HB_EXTERN hb_language_t
121hb_ot_tag_to_language (hb_tag_t tag);
122
123HB_EXTERN void
124hb_ot_tags_to_script_and_language (hb_tag_t script_tag,
125 hb_tag_t language_tag,
126 hb_script_t *script /* OUT */,
127 hb_language_t *language /* OUT */);
128
129
130/*
131 * GDEF
132 */
133
134HB_EXTERN hb_bool_t
135hb_ot_layout_has_glyph_classes (hb_face_t *face);
136
137/**
138 * hb_ot_layout_glyph_class_t:
139 * @HB_OT_LAYOUT_GLYPH_CLASS_UNCLASSIFIED: Glyphs not matching the other classifications
140 * @HB_OT_LAYOUT_GLYPH_CLASS_BASE_GLYPH: Spacing, single characters, capable of accepting marks
141 * @HB_OT_LAYOUT_GLYPH_CLASS_LIGATURE: Glyphs that represent ligation of multiple characters
142 * @HB_OT_LAYOUT_GLYPH_CLASS_MARK: Non-spacing, combining glyphs that represent marks
143 * @HB_OT_LAYOUT_GLYPH_CLASS_COMPONENT: Spacing glyphs that represent part of a single character
144 *
145 * The GDEF classes defined for glyphs.
146 *
147 **/
148typedef enum {
149 HB_OT_LAYOUT_GLYPH_CLASS_UNCLASSIFIED = 0,
150 HB_OT_LAYOUT_GLYPH_CLASS_BASE_GLYPH = 1,
151 HB_OT_LAYOUT_GLYPH_CLASS_LIGATURE = 2,
152 HB_OT_LAYOUT_GLYPH_CLASS_MARK = 3,
153 HB_OT_LAYOUT_GLYPH_CLASS_COMPONENT = 4
154} hb_ot_layout_glyph_class_t;
155
156HB_EXTERN hb_ot_layout_glyph_class_t
157hb_ot_layout_get_glyph_class (hb_face_t *face,
158 hb_codepoint_t glyph);
159
160HB_EXTERN void
161hb_ot_layout_get_glyphs_in_class (hb_face_t *face,
162 hb_ot_layout_glyph_class_t klass,
163 hb_set_t *glyphs /* OUT */);
164
165/* Not that useful. Provides list of attach points for a glyph that a
166 * client may want to cache */
167HB_EXTERN unsigned int
168hb_ot_layout_get_attach_points (hb_face_t *face,
169 hb_codepoint_t glyph,
170 unsigned int start_offset,
171 unsigned int *point_count /* IN/OUT */,
172 unsigned int *point_array /* OUT */);
173
174/* Ligature caret positions */
175HB_EXTERN unsigned int
176hb_ot_layout_get_ligature_carets (hb_font_t *font,
177 hb_direction_t direction,
178 hb_codepoint_t glyph,
179 unsigned int start_offset,
180 unsigned int *caret_count /* IN/OUT */,
181 hb_position_t *caret_array /* OUT */);
182
183
184/*
185 * GSUB/GPOS feature query and enumeration interface
186 */
187
188/**
189 * HB_OT_LAYOUT_NO_SCRIPT_INDEX:
190 *
191 * Special value for script index indicating unsupported script.
192 */
193#define HB_OT_LAYOUT_NO_SCRIPT_INDEX 0xFFFFu
194/**
195 * HB_OT_LAYOUT_NO_FEATURE_INDEX:
196 *
197 * Special value for feature index indicating unsupported feature.
198 */
199#define HB_OT_LAYOUT_NO_FEATURE_INDEX 0xFFFFu
200/**
201 * HB_OT_LAYOUT_DEFAULT_LANGUAGE_INDEX:
202 *
203 * Special value for language index indicating default or unsupported language.
204 */
205#define HB_OT_LAYOUT_DEFAULT_LANGUAGE_INDEX 0xFFFFu
206/**
207 * HB_OT_LAYOUT_NO_VARIATIONS_INDEX:
208 *
209 * Special value for variations index indicating unsupported variation.
210 */
211#define HB_OT_LAYOUT_NO_VARIATIONS_INDEX 0xFFFFFFFFu
212
213HB_EXTERN unsigned int
214hb_ot_layout_table_get_script_tags (hb_face_t *face,
215 hb_tag_t table_tag,
216 unsigned int start_offset,
217 unsigned int *script_count /* IN/OUT */,
218 hb_tag_t *script_tags /* OUT */);
219
220HB_EXTERN hb_bool_t
221hb_ot_layout_table_find_script (hb_face_t *face,
222 hb_tag_t table_tag,
223 hb_tag_t script_tag,
224 unsigned int *script_index /* OUT */);
225
226HB_EXTERN hb_bool_t
227hb_ot_layout_table_select_script (hb_face_t *face,
228 hb_tag_t table_tag,
229 unsigned int script_count,
230 const hb_tag_t *script_tags,
231 unsigned int *script_index /* OUT */,
232 hb_tag_t *chosen_script /* OUT */);
233
234HB_EXTERN unsigned int
235hb_ot_layout_table_get_feature_tags (hb_face_t *face,
236 hb_tag_t table_tag,
237 unsigned int start_offset,
238 unsigned int *feature_count /* IN/OUT */,
239 hb_tag_t *feature_tags /* OUT */);
240
241HB_EXTERN unsigned int
242hb_ot_layout_script_get_language_tags (hb_face_t *face,
243 hb_tag_t table_tag,
244 unsigned int script_index,
245 unsigned int start_offset,
246 unsigned int *language_count /* IN/OUT */,
247 hb_tag_t *language_tags /* OUT */);
248
249HB_EXTERN hb_bool_t
250hb_ot_layout_script_select_language (hb_face_t *face,
251 hb_tag_t table_tag,
252 unsigned int script_index,
253 unsigned int language_count,
254 const hb_tag_t *language_tags,
255 unsigned int *language_index /* OUT */);
256
257HB_EXTERN hb_bool_t
258hb_ot_layout_script_select_language2 (hb_face_t *face,
259 hb_tag_t table_tag,
260 unsigned int script_index,
261 unsigned int language_count,
262 const hb_tag_t *language_tags,
263 unsigned int *language_index /* OUT */,
264 hb_tag_t *chosen_language /* OUT */);
265
266HB_EXTERN hb_bool_t
267hb_ot_layout_language_get_required_feature_index (hb_face_t *face,
268 hb_tag_t table_tag,
269 unsigned int script_index,
270 unsigned int language_index,
271 unsigned int *feature_index /* OUT */);
272
273HB_EXTERN hb_bool_t
274hb_ot_layout_language_get_required_feature (hb_face_t *face,
275 hb_tag_t table_tag,
276 unsigned int script_index,
277 unsigned int language_index,
278 unsigned int *feature_index /* OUT */,
279 hb_tag_t *feature_tag /* OUT */);
280
281HB_EXTERN unsigned int
282hb_ot_layout_language_get_feature_indexes (hb_face_t *face,
283 hb_tag_t table_tag,
284 unsigned int script_index,
285 unsigned int language_index,
286 unsigned int start_offset,
287 unsigned int *feature_count /* IN/OUT */,
288 unsigned int *feature_indexes /* OUT */);
289
290HB_EXTERN unsigned int
291hb_ot_layout_language_get_feature_tags (hb_face_t *face,
292 hb_tag_t table_tag,
293 unsigned int script_index,
294 unsigned int language_index,
295 unsigned int start_offset,
296 unsigned int *feature_count /* IN/OUT */,
297 hb_tag_t *feature_tags /* OUT */);
298
299HB_EXTERN hb_bool_t
300hb_ot_layout_language_find_feature (hb_face_t *face,
301 hb_tag_t table_tag,
302 unsigned int script_index,
303 unsigned int language_index,
304 hb_tag_t feature_tag,
305 unsigned int *feature_index /* OUT */);
306
307HB_EXTERN unsigned int
308hb_ot_layout_feature_get_lookups (hb_face_t *face,
309 hb_tag_t table_tag,
310 unsigned int feature_index,
311 unsigned int start_offset,
312 unsigned int *lookup_count /* IN/OUT */,
313 unsigned int *lookup_indexes /* OUT */);
314
315HB_EXTERN unsigned int
316hb_ot_layout_table_get_lookup_count (hb_face_t *face,
317 hb_tag_t table_tag);
318
319HB_EXTERN void
320hb_ot_layout_collect_features (hb_face_t *face,
321 hb_tag_t table_tag,
322 const hb_tag_t *scripts,
323 const hb_tag_t *languages,
324 const hb_tag_t *features,
325 hb_set_t *feature_indexes /* OUT */);
326
327HB_EXTERN void
328hb_ot_layout_collect_features_map (hb_face_t *face,
329 hb_tag_t table_tag,
330 unsigned script_index,
331 unsigned language_index,
332 hb_map_t *feature_map /* OUT */);
333
334HB_EXTERN void
335hb_ot_layout_collect_lookups (hb_face_t *face,
336 hb_tag_t table_tag,
337 const hb_tag_t *scripts,
338 const hb_tag_t *languages,
339 const hb_tag_t *features,
340 hb_set_t *lookup_indexes /* OUT */);
341
342HB_EXTERN void
343hb_ot_layout_lookup_collect_glyphs (hb_face_t *face,
344 hb_tag_t table_tag,
345 unsigned int lookup_index,
346 hb_set_t *glyphs_before, /* OUT. May be NULL */
347 hb_set_t *glyphs_input, /* OUT. May be NULL */
348 hb_set_t *glyphs_after, /* OUT. May be NULL */
349 hb_set_t *glyphs_output /* OUT. May be NULL */);
350
351
352/* Variations support */
353
354HB_EXTERN hb_bool_t
355hb_ot_layout_table_find_feature_variations (hb_face_t *face,
356 hb_tag_t table_tag,
357 const int *coords,
358 unsigned int num_coords,
359 unsigned int *variations_index /* out */);
360
361HB_EXTERN unsigned int
362hb_ot_layout_feature_with_variations_get_lookups (hb_face_t *face,
363 hb_tag_t table_tag,
364 unsigned int feature_index,
365 unsigned int variations_index,
366 unsigned int start_offset,
367 unsigned int *lookup_count /* IN/OUT */,
368 unsigned int *lookup_indexes /* OUT */);
369
370
371/*
372 * GSUB
373 */
374
375HB_EXTERN hb_bool_t
376hb_ot_layout_has_substitution (hb_face_t *face);
377
378HB_EXTERN unsigned
379hb_ot_layout_lookup_get_glyph_alternates (hb_face_t *face,
380 unsigned lookup_index,
381 hb_codepoint_t glyph,
382 unsigned start_offset,
383 unsigned *alternate_count /* IN/OUT */,
384 hb_codepoint_t *alternate_glyphs /* OUT */);
385
386HB_EXTERN hb_bool_t
387hb_ot_layout_lookup_would_substitute (hb_face_t *face,
388 unsigned int lookup_index,
389 const hb_codepoint_t *glyphs,
390 unsigned int glyphs_length,
391 hb_bool_t zero_context);
392
393HB_EXTERN void
394hb_ot_layout_lookup_substitute_closure (hb_face_t *face,
395 unsigned int lookup_index,
396 hb_set_t *glyphs
397 /*TODO , hb_bool_t inclusive */);
398
399HB_EXTERN void
400hb_ot_layout_lookups_substitute_closure (hb_face_t *face,
401 const hb_set_t *lookups,
402 hb_set_t *glyphs);
403
404
405/*
406 * GPOS
407 */
408
409HB_EXTERN hb_bool_t
410hb_ot_layout_has_positioning (hb_face_t *face);
411
412/* Optical 'size' feature info. Returns true if found.
413 * https://docs.microsoft.com/en-us/typography/opentype/spec/features_pt#size */
414HB_EXTERN hb_bool_t
415hb_ot_layout_get_size_params (hb_face_t *face,
416 unsigned int *design_size, /* OUT. May be NULL */
417 unsigned int *subfamily_id, /* OUT. May be NULL */
418 hb_ot_name_id_t *subfamily_name_id, /* OUT. May be NULL */
419 unsigned int *range_start, /* OUT. May be NULL */
420 unsigned int *range_end /* OUT. May be NULL */);
421
422HB_EXTERN hb_position_t
423hb_ot_layout_lookup_get_optical_bound (hb_font_t *font,
424 unsigned lookup_index,
425 hb_direction_t direction,
426 hb_codepoint_t glyph);
427
428
429/*
430 * GSUB/GPOS
431 */
432
433HB_EXTERN hb_bool_t
434hb_ot_layout_feature_get_name_ids (hb_face_t *face,
435 hb_tag_t table_tag,
436 unsigned int feature_index,
437 hb_ot_name_id_t *label_id /* OUT. May be NULL */,
438 hb_ot_name_id_t *tooltip_id /* OUT. May be NULL */,
439 hb_ot_name_id_t *sample_id /* OUT. May be NULL */,
440 unsigned int *num_named_parameters /* OUT. May be NULL */,
441 hb_ot_name_id_t *first_param_id /* OUT. May be NULL */);
442
443
444HB_EXTERN unsigned int
445hb_ot_layout_feature_get_characters (hb_face_t *face,
446 hb_tag_t table_tag,
447 unsigned int feature_index,
448 unsigned int start_offset,
449 unsigned int *char_count /* IN/OUT. May be NULL */,
450 hb_codepoint_t *characters /* OUT. May be NULL */);
451
452
453/*
454 * BASE
455 */
456
457HB_EXTERN hb_bool_t
458hb_ot_layout_get_font_extents (hb_font_t *font,
459 hb_direction_t direction,
460 hb_tag_t script_tag,
461 hb_tag_t language_tag,
462 hb_font_extents_t *extents);
463
464HB_EXTERN hb_bool_t
465hb_ot_layout_get_font_extents2 (hb_font_t *font,
466 hb_direction_t direction,
467 hb_script_t script,
468 hb_language_t language,
469 hb_font_extents_t *extents);
470
471/**
472 * hb_ot_layout_baseline_tag_t:
473 * @HB_OT_LAYOUT_BASELINE_TAG_ROMAN: The baseline used by alphabetic scripts such as Latin, Cyrillic and Greek.
474 * In vertical writing mode, the alphabetic baseline for characters rotated 90 degrees clockwise.
475 * (This would not apply to alphabetic characters that remain upright in vertical writing mode, since these
476 * characters are not rotated.)
477 * @HB_OT_LAYOUT_BASELINE_TAG_HANGING: The hanging baseline. In horizontal direction, this is the horizontal
478 * line from which syllables seem, to hang in Tibetan and other similar scripts. In vertical writing mode,
479 * for Tibetan (or some other similar script) characters rotated 90 degrees clockwise.
480 * @HB_OT_LAYOUT_BASELINE_TAG_IDEO_FACE_BOTTOM_OR_LEFT: Ideographic character face bottom or left edge,
481 * if the direction is horizontal or vertical, respectively.
482 * @HB_OT_LAYOUT_BASELINE_TAG_IDEO_FACE_TOP_OR_RIGHT: Ideographic character face top or right edge,
483 * if the direction is horizontal or vertical, respectively.
484 * @HB_OT_LAYOUT_BASELINE_TAG_IDEO_FACE_CENTRAL: The center of the ideographic character face. Since: 4.0.0
485 * @HB_OT_LAYOUT_BASELINE_TAG_IDEO_EMBOX_BOTTOM_OR_LEFT: Ideographic em-box bottom or left edge,
486 * if the direction is horizontal or vertical, respectively.
487 * @HB_OT_LAYOUT_BASELINE_TAG_IDEO_EMBOX_TOP_OR_RIGHT: Ideographic em-box top or right edge baseline,
488 * @HB_OT_LAYOUT_BASELINE_TAG_IDEO_EMBOX_CENTRAL: The center of the ideographic em-box. Since: 4.0.0
489 * if the direction is horizontal or vertical, respectively.
490 * @HB_OT_LAYOUT_BASELINE_TAG_MATH: The baseline about which mathematical characters are centered.
491 * In vertical writing mode when mathematical characters rotated 90 degrees clockwise, are centered.
492 *
493 * Baseline tags from [Baseline Tags](https://docs.microsoft.com/en-us/typography/opentype/spec/baselinetags) registry.
494 *
495 * Since: 2.6.0
496 */
497typedef enum {
498 HB_OT_LAYOUT_BASELINE_TAG_ROMAN = HB_TAG ('r','o','m','n'),
499 HB_OT_LAYOUT_BASELINE_TAG_HANGING = HB_TAG ('h','a','n','g'),
500 HB_OT_LAYOUT_BASELINE_TAG_IDEO_FACE_BOTTOM_OR_LEFT = HB_TAG ('i','c','f','b'),
501 HB_OT_LAYOUT_BASELINE_TAG_IDEO_FACE_TOP_OR_RIGHT = HB_TAG ('i','c','f','t'),
502 HB_OT_LAYOUT_BASELINE_TAG_IDEO_FACE_CENTRAL = HB_TAG ('I','c','f','c'),
503 HB_OT_LAYOUT_BASELINE_TAG_IDEO_EMBOX_BOTTOM_OR_LEFT = HB_TAG ('i','d','e','o'),
504 HB_OT_LAYOUT_BASELINE_TAG_IDEO_EMBOX_TOP_OR_RIGHT = HB_TAG ('i','d','t','p'),
505 HB_OT_LAYOUT_BASELINE_TAG_IDEO_EMBOX_CENTRAL = HB_TAG ('I','d','c','e'),
506 HB_OT_LAYOUT_BASELINE_TAG_MATH = HB_TAG ('m','a','t','h'),
507
508 /*< private >*/
509 _HB_OT_LAYOUT_BASELINE_TAG_MAX_VALUE = HB_TAG_MAX_SIGNED /*< skip >*/
510} hb_ot_layout_baseline_tag_t;
511
512HB_EXTERN hb_ot_layout_baseline_tag_t
513hb_ot_layout_get_horizontal_baseline_tag_for_script (hb_script_t script);
514
515HB_EXTERN hb_bool_t
516hb_ot_layout_get_baseline (hb_font_t *font,
517 hb_ot_layout_baseline_tag_t baseline_tag,
518 hb_direction_t direction,
519 hb_tag_t script_tag,
520 hb_tag_t language_tag,
521 hb_position_t *coord /* OUT. May be NULL. */);
522
523HB_EXTERN hb_bool_t
524hb_ot_layout_get_baseline2 (hb_font_t *font,
525 hb_ot_layout_baseline_tag_t baseline_tag,
526 hb_direction_t direction,
527 hb_script_t script,
528 hb_language_t language,
529 hb_position_t *coord /* OUT. May be NULL. */);
530
531HB_EXTERN void
532hb_ot_layout_get_baseline_with_fallback (hb_font_t *font,
533 hb_ot_layout_baseline_tag_t baseline_tag,
534 hb_direction_t direction,
535 hb_tag_t script_tag,
536 hb_tag_t language_tag,
537 hb_position_t *coord /* OUT */);
538
539HB_EXTERN void
540hb_ot_layout_get_baseline_with_fallback2 (hb_font_t *font,
541 hb_ot_layout_baseline_tag_t baseline_tag,
542 hb_direction_t direction,
543 hb_script_t script,
544 hb_language_t language,
545 hb_position_t *coord /* OUT */);
546
547HB_END_DECLS
548
549#endif /* HB_OT_LAYOUT_H */
550