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#ifndef HB_OT_H_IN
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#define HB_OT_TAG_BASE HB_TAG('B','A','S','E')
42#define HB_OT_TAG_GDEF HB_TAG('G','D','E','F')
43#define HB_OT_TAG_GSUB HB_TAG('G','S','U','B')
44#define HB_OT_TAG_GPOS HB_TAG('G','P','O','S')
45#define HB_OT_TAG_JSTF HB_TAG('J','S','T','F')
46
47
48/*
49 * Script & Language tags.
50 */
51
52#define HB_OT_TAG_DEFAULT_SCRIPT HB_TAG ('D', 'F', 'L', 'T')
53#define HB_OT_TAG_DEFAULT_LANGUAGE HB_TAG ('d', 'f', 'l', 't')
54
55/**
56 * HB_OT_MAX_TAGS_PER_SCRIPT:
57 *
58 * Since: 2.0.0
59 **/
60#define HB_OT_MAX_TAGS_PER_SCRIPT 3u
61/**
62 * HB_OT_MAX_TAGS_PER_LANGUAGE:
63 *
64 * Since: 2.0.0
65 **/
66#define HB_OT_MAX_TAGS_PER_LANGUAGE 3u
67
68HB_EXTERN void
69hb_ot_tags_from_script_and_language (hb_script_t script,
70 hb_language_t language,
71 unsigned int *script_count /* IN/OUT */,
72 hb_tag_t *script_tags /* OUT */,
73 unsigned int *language_count /* IN/OUT */,
74 hb_tag_t *language_tags /* OUT */);
75
76HB_EXTERN hb_script_t
77hb_ot_tag_to_script (hb_tag_t tag);
78
79HB_EXTERN hb_language_t
80hb_ot_tag_to_language (hb_tag_t tag);
81
82HB_EXTERN void
83hb_ot_tags_to_script_and_language (hb_tag_t script_tag,
84 hb_tag_t language_tag,
85 hb_script_t *script /* OUT */,
86 hb_language_t *language /* OUT */);
87
88
89/*
90 * GDEF
91 */
92
93HB_EXTERN hb_bool_t
94hb_ot_layout_has_glyph_classes (hb_face_t *face);
95
96/**
97 * hb_ot_layout_glyph_class_t:
98 * @HB_OT_LAYOUT_GLYPH_CLASS_UNCLASSIFIED: Glyphs not matching the other classifications
99 * @HB_OT_LAYOUT_GLYPH_CLASS_BASE_GLYPH: Spacing, single characters, capable of accepting marks
100 * @HB_OT_LAYOUT_GLYPH_CLASS_LIGATURE: Glyphs that represent ligation of multiple characters
101 * @HB_OT_LAYOUT_GLYPH_CLASS_MARK: Non-spacing, combining glyphs that represent marks
102 * @HB_OT_LAYOUT_GLYPH_CLASS_COMPONENT: Spacing glyphs that represent part of a single character
103 *
104 * The GDEF classes defined for glyphs.
105 *
106 **/
107typedef enum {
108 HB_OT_LAYOUT_GLYPH_CLASS_UNCLASSIFIED = 0,
109 HB_OT_LAYOUT_GLYPH_CLASS_BASE_GLYPH = 1,
110 HB_OT_LAYOUT_GLYPH_CLASS_LIGATURE = 2,
111 HB_OT_LAYOUT_GLYPH_CLASS_MARK = 3,
112 HB_OT_LAYOUT_GLYPH_CLASS_COMPONENT = 4
113} hb_ot_layout_glyph_class_t;
114
115HB_EXTERN hb_ot_layout_glyph_class_t
116hb_ot_layout_get_glyph_class (hb_face_t *face,
117 hb_codepoint_t glyph);
118
119HB_EXTERN void
120hb_ot_layout_get_glyphs_in_class (hb_face_t *face,
121 hb_ot_layout_glyph_class_t klass,
122 hb_set_t *glyphs /* OUT */);
123
124/* Not that useful. Provides list of attach points for a glyph that a
125 * client may want to cache */
126HB_EXTERN unsigned int
127hb_ot_layout_get_attach_points (hb_face_t *face,
128 hb_codepoint_t glyph,
129 unsigned int start_offset,
130 unsigned int *point_count /* IN/OUT */,
131 unsigned int *point_array /* OUT */);
132
133/* Ligature caret positions */
134HB_EXTERN unsigned int
135hb_ot_layout_get_ligature_carets (hb_font_t *font,
136 hb_direction_t direction,
137 hb_codepoint_t glyph,
138 unsigned int start_offset,
139 unsigned int *caret_count /* IN/OUT */,
140 hb_position_t *caret_array /* OUT */);
141
142
143/*
144 * GSUB/GPOS feature query and enumeration interface
145 */
146
147#define HB_OT_LAYOUT_NO_SCRIPT_INDEX 0xFFFFu
148#define HB_OT_LAYOUT_NO_FEATURE_INDEX 0xFFFFu
149#define HB_OT_LAYOUT_DEFAULT_LANGUAGE_INDEX 0xFFFFu
150#define HB_OT_LAYOUT_NO_VARIATIONS_INDEX 0xFFFFFFFFu
151
152HB_EXTERN unsigned int
153hb_ot_layout_table_get_script_tags (hb_face_t *face,
154 hb_tag_t table_tag,
155 unsigned int start_offset,
156 unsigned int *script_count /* IN/OUT */,
157 hb_tag_t *script_tags /* OUT */);
158
159HB_EXTERN hb_bool_t
160hb_ot_layout_table_find_script (hb_face_t *face,
161 hb_tag_t table_tag,
162 hb_tag_t script_tag,
163 unsigned int *script_index /* OUT */);
164
165HB_EXTERN hb_bool_t
166hb_ot_layout_table_select_script (hb_face_t *face,
167 hb_tag_t table_tag,
168 unsigned int script_count,
169 const hb_tag_t *script_tags,
170 unsigned int *script_index /* OUT */,
171 hb_tag_t *chosen_script /* OUT */);
172
173HB_EXTERN unsigned int
174hb_ot_layout_table_get_feature_tags (hb_face_t *face,
175 hb_tag_t table_tag,
176 unsigned int start_offset,
177 unsigned int *feature_count /* IN/OUT */,
178 hb_tag_t *feature_tags /* OUT */);
179
180HB_EXTERN unsigned int
181hb_ot_layout_script_get_language_tags (hb_face_t *face,
182 hb_tag_t table_tag,
183 unsigned int script_index,
184 unsigned int start_offset,
185 unsigned int *language_count /* IN/OUT */,
186 hb_tag_t *language_tags /* OUT */);
187
188HB_EXTERN hb_bool_t
189hb_ot_layout_script_select_language (hb_face_t *face,
190 hb_tag_t table_tag,
191 unsigned int script_index,
192 unsigned int language_count,
193 const hb_tag_t *language_tags,
194 unsigned int *language_index /* OUT */);
195
196HB_EXTERN hb_bool_t
197hb_ot_layout_language_get_required_feature_index (hb_face_t *face,
198 hb_tag_t table_tag,
199 unsigned int script_index,
200 unsigned int language_index,
201 unsigned int *feature_index /* OUT */);
202
203HB_EXTERN hb_bool_t
204hb_ot_layout_language_get_required_feature (hb_face_t *face,
205 hb_tag_t table_tag,
206 unsigned int script_index,
207 unsigned int language_index,
208 unsigned int *feature_index /* OUT */,
209 hb_tag_t *feature_tag /* OUT */);
210
211HB_EXTERN unsigned int
212hb_ot_layout_language_get_feature_indexes (hb_face_t *face,
213 hb_tag_t table_tag,
214 unsigned int script_index,
215 unsigned int language_index,
216 unsigned int start_offset,
217 unsigned int *feature_count /* IN/OUT */,
218 unsigned int *feature_indexes /* OUT */);
219
220HB_EXTERN unsigned int
221hb_ot_layout_language_get_feature_tags (hb_face_t *face,
222 hb_tag_t table_tag,
223 unsigned int script_index,
224 unsigned int language_index,
225 unsigned int start_offset,
226 unsigned int *feature_count /* IN/OUT */,
227 hb_tag_t *feature_tags /* OUT */);
228
229HB_EXTERN hb_bool_t
230hb_ot_layout_language_find_feature (hb_face_t *face,
231 hb_tag_t table_tag,
232 unsigned int script_index,
233 unsigned int language_index,
234 hb_tag_t feature_tag,
235 unsigned int *feature_index /* OUT */);
236
237HB_EXTERN unsigned int
238hb_ot_layout_feature_get_lookups (hb_face_t *face,
239 hb_tag_t table_tag,
240 unsigned int feature_index,
241 unsigned int start_offset,
242 unsigned int *lookup_count /* IN/OUT */,
243 unsigned int *lookup_indexes /* OUT */);
244
245HB_EXTERN unsigned int
246hb_ot_layout_table_get_lookup_count (hb_face_t *face,
247 hb_tag_t table_tag);
248
249HB_EXTERN void
250hb_ot_layout_collect_features (hb_face_t *face,
251 hb_tag_t table_tag,
252 const hb_tag_t *scripts,
253 const hb_tag_t *languages,
254 const hb_tag_t *features,
255 hb_set_t *feature_indexes /* OUT */);
256
257HB_EXTERN void
258hb_ot_layout_collect_lookups (hb_face_t *face,
259 hb_tag_t table_tag,
260 const hb_tag_t *scripts,
261 const hb_tag_t *languages,
262 const hb_tag_t *features,
263 hb_set_t *lookup_indexes /* OUT */);
264
265HB_EXTERN void
266hb_ot_layout_lookup_collect_glyphs (hb_face_t *face,
267 hb_tag_t table_tag,
268 unsigned int lookup_index,
269 hb_set_t *glyphs_before, /* OUT. May be NULL */
270 hb_set_t *glyphs_input, /* OUT. May be NULL */
271 hb_set_t *glyphs_after, /* OUT. May be NULL */
272 hb_set_t *glyphs_output /* OUT. May be NULL */);
273
274#ifdef HB_NOT_IMPLEMENTED
275typedef struct
276{
277 const hb_codepoint_t *before,
278 unsigned int before_length,
279 const hb_codepoint_t *input,
280 unsigned int input_length,
281 const hb_codepoint_t *after,
282 unsigned int after_length,
283} hb_ot_layout_glyph_sequence_t;
284
285typedef hb_bool_t
286(*hb_ot_layout_glyph_sequence_func_t) (hb_font_t *font,
287 hb_tag_t table_tag,
288 unsigned int lookup_index,
289 const hb_ot_layout_glyph_sequence_t *sequence,
290 void *user_data);
291
292HB_EXTERN void
293Xhb_ot_layout_lookup_enumerate_sequences (hb_face_t *face,
294 hb_tag_t table_tag,
295 unsigned int lookup_index,
296 hb_ot_layout_glyph_sequence_func_t callback,
297 void *user_data);
298#endif
299
300/* Variations support */
301
302HB_EXTERN hb_bool_t
303hb_ot_layout_table_find_feature_variations (hb_face_t *face,
304 hb_tag_t table_tag,
305 const int *coords,
306 unsigned int num_coords,
307 unsigned int *variations_index /* out */);
308
309HB_EXTERN unsigned int
310hb_ot_layout_feature_with_variations_get_lookups (hb_face_t *face,
311 hb_tag_t table_tag,
312 unsigned int feature_index,
313 unsigned int variations_index,
314 unsigned int start_offset,
315 unsigned int *lookup_count /* IN/OUT */,
316 unsigned int *lookup_indexes /* OUT */);
317
318
319/*
320 * GSUB
321 */
322
323HB_EXTERN hb_bool_t
324hb_ot_layout_has_substitution (hb_face_t *face);
325
326HB_EXTERN unsigned
327hb_ot_layout_lookup_get_glyph_alternates (hb_face_t *face,
328 unsigned lookup_index,
329 hb_codepoint_t glyph,
330 unsigned start_offset,
331 unsigned *alternate_count /* IN/OUT */,
332 hb_codepoint_t *alternate_glyphs /* OUT */);
333
334HB_EXTERN hb_bool_t
335hb_ot_layout_lookup_would_substitute (hb_face_t *face,
336 unsigned int lookup_index,
337 const hb_codepoint_t *glyphs,
338 unsigned int glyphs_length,
339 hb_bool_t zero_context);
340
341HB_EXTERN void
342hb_ot_layout_lookup_substitute_closure (hb_face_t *face,
343 unsigned int lookup_index,
344 hb_set_t *glyphs
345 /*TODO , hb_bool_t inclusive */);
346
347HB_EXTERN void
348hb_ot_layout_lookups_substitute_closure (hb_face_t *face,
349 const hb_set_t *lookups,
350 hb_set_t *glyphs);
351
352
353#ifdef HB_NOT_IMPLEMENTED
354/* Note: You better have GDEF when using this API, or marks won't do much. */
355HB_EXTERN hb_bool_t
356Xhb_ot_layout_lookup_substitute (hb_font_t *font,
357 unsigned int lookup_index,
358 const hb_ot_layout_glyph_sequence_t *sequence,
359 unsigned int out_size,
360 hb_codepoint_t *glyphs_out, /* OUT */
361 unsigned int *clusters_out, /* OUT */
362 unsigned int *out_length /* OUT */);
363#endif
364
365
366/*
367 * GPOS
368 */
369
370HB_EXTERN hb_bool_t
371hb_ot_layout_has_positioning (hb_face_t *face);
372
373#ifdef HB_NOT_IMPLEMENTED
374/* Note: You better have GDEF when using this API, or marks won't do much. */
375HB_EXTERN hb_bool_t
376Xhb_ot_layout_lookup_position (hb_font_t *font,
377 unsigned int lookup_index,
378 const hb_ot_layout_glyph_sequence_t *sequence,
379 hb_glyph_position_t *positions /* IN / OUT */);
380#endif
381
382/* Optical 'size' feature info. Returns true if found.
383 * https://docs.microsoft.com/en-us/typography/opentype/spec/features_pt#size */
384HB_EXTERN hb_bool_t
385hb_ot_layout_get_size_params (hb_face_t *face,
386 unsigned int *design_size, /* OUT. May be NULL */
387 unsigned int *subfamily_id, /* OUT. May be NULL */
388 hb_ot_name_id_t *subfamily_name_id, /* OUT. May be NULL */
389 unsigned int *range_start, /* OUT. May be NULL */
390 unsigned int *range_end /* OUT. May be NULL */);
391
392
393HB_EXTERN hb_bool_t
394hb_ot_layout_feature_get_name_ids (hb_face_t *face,
395 hb_tag_t table_tag,
396 unsigned int feature_index,
397 hb_ot_name_id_t *label_id /* OUT. May be NULL */,
398 hb_ot_name_id_t *tooltip_id /* OUT. May be NULL */,
399 hb_ot_name_id_t *sample_id /* OUT. May be NULL */,
400 unsigned int *num_named_parameters /* OUT. May be NULL */,
401 hb_ot_name_id_t *first_param_id /* OUT. May be NULL */);
402
403
404HB_EXTERN unsigned int
405hb_ot_layout_feature_get_characters (hb_face_t *face,
406 hb_tag_t table_tag,
407 unsigned int feature_index,
408 unsigned int start_offset,
409 unsigned int *char_count /* IN/OUT. May be NULL */,
410 hb_codepoint_t *characters /* OUT. May be NULL */);
411
412/*
413 * BASE
414 */
415
416/**
417 * hb_ot_layout_baseline_tag_t:
418 * @HB_OT_LAYOUT_BASELINE_TAG_ROMAN: The baseline used by alphabetic scripts such as Latin, Cyrillic and Greek.
419 * In vertical writing mode, the alphabetic baseline for characters rotated 90 degrees clockwise.
420 * (This would not apply to alphabetic characters that remain upright in vertical writing mode, since these
421 * characters are not rotated.)
422 * @HB_OT_LAYOUT_BASELINE_TAG_HANGING: The hanging baseline. In horizontal direction, this is the horizontal
423 * line from which syllables seem, to hang in Tibetan and other similar scripts. In vertical writing mode,
424 * for Tibetan (or some other similar script) characters rotated 90 degrees clockwise.
425 * @HB_OT_LAYOUT_BASELINE_TAG_IDEO_FACE_BOTTOM_OR_LEFT: Ideographic character face bottom or left edge,
426 * if the direction is horizontal or vertical, respectively.
427 * @HB_OT_LAYOUT_BASELINE_TAG_IDEO_FACE_TOP_OR_RIGHT: Ideographic character face top or right edge,
428 * if the direction is horizontal or vertical, respectively.
429 * @HB_OT_LAYOUT_BASELINE_TAG_IDEO_EMBOX_BOTTOM_OR_LEFT: Ideographic em-box bottom or left edge,
430 * if the direction is horizontal or vertical, respectively.
431 * @HB_OT_LAYOUT_BASELINE_TAG_IDEO_EMBOX_TOP_OR_RIGHT: Ideographic em-box top or right edge baseline,
432 * if the direction is horizontal or vertical, respectively.
433 * @HB_OT_LAYOUT_BASELINE_TAG_MATH: The baseline about which mathematical characters are centered.
434 * In vertical writing mode when mathematical characters rotated 90 degrees clockwise, are centered.
435 *
436 * Baseline tags from https://docs.microsoft.com/en-us/typography/opentype/spec/baselinetags
437 *
438 * Since: 2.6.0
439 */
440typedef enum {
441 HB_OT_LAYOUT_BASELINE_TAG_ROMAN = HB_TAG ('r','o','m','n'),
442 HB_OT_LAYOUT_BASELINE_TAG_HANGING = HB_TAG ('h','a','n','g'),
443 HB_OT_LAYOUT_BASELINE_TAG_IDEO_FACE_BOTTOM_OR_LEFT = HB_TAG ('i','c','f','b'),
444 HB_OT_LAYOUT_BASELINE_TAG_IDEO_FACE_TOP_OR_RIGHT = HB_TAG ('i','c','f','t'),
445 HB_OT_LAYOUT_BASELINE_TAG_IDEO_EMBOX_BOTTOM_OR_LEFT = HB_TAG ('i','d','e','o'),
446 HB_OT_LAYOUT_BASELINE_TAG_IDEO_EMBOX_TOP_OR_RIGHT = HB_TAG ('i','d','t','p'),
447 HB_OT_LAYOUT_BASELINE_TAG_MATH = HB_TAG ('m','a','t','h'),
448
449 _HB_OT_LAYOUT_BASELINE_TAG_MAX_VALUE = HB_TAG_MAX_SIGNED /*< skip >*/
450} hb_ot_layout_baseline_tag_t;
451
452HB_EXTERN hb_bool_t
453hb_ot_layout_get_baseline (hb_font_t *font,
454 hb_ot_layout_baseline_tag_t baseline_tag,
455 hb_direction_t direction,
456 hb_tag_t script_tag,
457 hb_tag_t language_tag,
458 hb_position_t *coord /* OUT. May be NULL. */);
459
460HB_END_DECLS
461
462#endif /* HB_OT_LAYOUT_H */
463

source code of include/harfbuzz/hb-ot-layout.h