w32tex
About: TeX Live provides a comprehensive TeX system including all the major TeX-related programs, macro packages, and fonts that are free software. Windows sources.
  Fossies Dox: w32tex-src.tar.xz  ("unofficial" and yet experimental doxygen-generated source code documentation)  

hb-ot-layout.cc
Go to the documentation of this file.
1 /*
2  * Copyright © 1998-2004 David Turner and Werner Lemberg
3  * Copyright © 2006 Behdad Esfahbod
4  * Copyright © 2007,2008,2009 Red Hat, Inc.
5  * Copyright © 2012,2013 Google, Inc.
6  *
7  * This is part of HarfBuzz, a text shaping library.
8  *
9  * Permission is hereby granted, without written agreement and without
10  * license or royalty fees, to use, copy, modify, and distribute this
11  * software and its documentation for any purpose, provided that the
12  * above copyright notice and the following two paragraphs appear in
13  * all copies of this software.
14  *
15  * IN NO EVENT SHALL THE COPYRIGHT HOLDER BE LIABLE TO ANY PARTY FOR
16  * DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES
17  * ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN
18  * IF THE COPYRIGHT HOLDER HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH
19  * DAMAGE.
20  *
21  * THE COPYRIGHT HOLDER SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING,
22  * BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
23  * FITNESS FOR A PARTICULAR PURPOSE. THE SOFTWARE PROVIDED HEREUNDER IS
24  * ON AN "AS IS" BASIS, AND THE COPYRIGHT HOLDER HAS NO OBLIGATION TO
25  * PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.
26  *
27  * Red Hat Author(s): Behdad Esfahbod
28  * Google Author(s): Behdad Esfahbod
29  */
30 
31 #include "hb.hh"
32 
33 #ifndef HB_NO_OT_LAYOUT
34 
35 #ifdef HB_NO_OT_TAG
36 #error "Cannot compile hb-ot-layout.cc with HB_NO_OT_TAG."
37 #endif
38 
39 #include "hb-open-type.hh"
40 #include "hb-ot-layout.hh"
41 #include "hb-ot-face.hh"
42 #include "hb-ot-map.hh"
43 #include "hb-map.hh"
44 
45 #include "hb-ot-kern-table.hh"
49 #include "hb-ot-layout-base-table.hh" // Just so we compile it; unused otherwise.
50 #include "hb-ot-layout-jstf-table.hh" // Just so we compile it; unused otherwise.
51 #include "hb-ot-name-table.hh"
52 #include "hb-ot-os2-table.hh"
53 
55 #include "hb-aat-layout-opbd-table.hh" // Just so we compile it; unused otherwise.
56 
57 /**
58  * SECTION:hb-ot-layout
59  * @title: hb-ot-layout
60  * @short_description: OpenType Layout
61  * @include: hb-ot.h
62  *
63  * Functions for querying OpenType Layout features in the font face.
64  **/
65 
66 
67 /*
68  * kern
69  */
70 
71 #ifndef HB_NO_OT_KERN
72 /**
73  * hb_ot_layout_has_kerning:
74  * @face: The #hb_face_t to work on
75  *
76  * Tests whether a face includes any kerning data in the 'kern' table.
77  * Does NOT test for kerning lookups in the GPOS table.
78  *
79  * Return value: %true if data found, false otherwise
80  *
81  **/
82 bool
84 {
85  return face->table.kern->has_data ();
86 }
87 
88 /**
89  * hb_ot_layout_has_machine_kerning:
90  * @face: The #hb_face_t to work on
91  *
92  * Tests whether a face includes any state-machine kerning in the 'kern' table.
93  * Does NOT examine the GPOS table.
94  *
95  * Return value: %true if data found, false otherwise
96  *
97  **/
98 bool
100 {
101  return face->table.kern->has_state_machine ();
102 }
103 
104 /**
105  * hb_ot_layout_has_cross_kerning:
106  * @face: The #hb_face_t to work on
107  *
108  * Tests whether a face has any cross-stream kerning (i.e., kerns
109  * that make adjustments perpendicular to the direction of the text
110  * flow: Y adjustments in horizontal text or X adjustments in
111  * vertical text) in the 'kern' table.
112  *
113  * Does NOT examine the GPOS table.
114  *
115  * Return value: %true is data found, false otherwise
116  *
117  **/
118 bool
120 {
121  return face->table.kern->has_cross_stream ();
122 }
123 
124 void
126  hb_font_t *font,
128 {
129  hb_blob_t *blob = font->face->table.kern.get_blob ();
130  const AAT::kern& kern = *blob->as<AAT::kern> ();
131 
132  AAT::hb_aat_apply_context_t c (plan, font, buffer, blob);
133 
134  kern.apply (&c);
135 }
136 #endif
137 
138 
139 /*
140  * GDEF
141  */
142 
143 bool
145  hb_face_t *face) const
146 {
147 #ifdef HB_NO_OT_LAYOUT_BLACKLIST
148  return false;
149 #endif
150  /* The ugly business of blocklisting individual fonts' tables happen here!
151  * See this thread for why we finally had to bend in and do this:
152  * https://lists.freedesktop.org/archives/harfbuzz/2016-February/005489.html
153  *
154  * In certain versions of Times New Roman Italic and Bold Italic,
155  * ASCII double quotation mark U+0022 has wrong glyph class 3 (mark)
156  * in GDEF. Many versions of Tahoma have bad GDEF tables that
157  * incorrectly classify some spacing marks such as certain IPA
158  * symbols as glyph class 3. So do older versions of Microsoft
159  * Himalaya, and the version of Cantarell shipped by Ubuntu 16.04.
160  *
161  * Nuke the GDEF tables of to avoid unwanted width-zeroing.
162  *
163  * See https://bugzilla.mozilla.org/show_bug.cgi?id=1279925
164  * https://bugzilla.mozilla.org/show_bug.cgi?id=1279693
165  * https://bugzilla.mozilla.org/show_bug.cgi?id=1279875
166  */
167  switch HB_CODEPOINT_ENCODE3(blob->length,
168  face->table.GSUB->table.get_length (),
169  face->table.GPOS->table.get_length ())
170  {
171  /* sha1sum:c5ee92f0bca4bfb7d06c4d03e8cf9f9cf75d2e8a Windows 7? timesi.ttf */
172  case HB_CODEPOINT_ENCODE3 (442, 2874, 42038):
173  /* sha1sum:37fc8c16a0894ab7b749e35579856c73c840867b Windows 7? timesbi.ttf */
174  case HB_CODEPOINT_ENCODE3 (430, 2874, 40662):
175  /* sha1sum:19fc45110ea6cd3cdd0a5faca256a3797a069a80 Windows 7 timesi.ttf */
176  case HB_CODEPOINT_ENCODE3 (442, 2874, 39116):
177  /* sha1sum:6d2d3c9ed5b7de87bc84eae0df95ee5232ecde26 Windows 7 timesbi.ttf */
178  case HB_CODEPOINT_ENCODE3 (430, 2874, 39374):
179  /* sha1sum:8583225a8b49667c077b3525333f84af08c6bcd8 OS X 10.11.3 Times New Roman Italic.ttf */
180  case HB_CODEPOINT_ENCODE3 (490, 3046, 41638):
181  /* sha1sum:ec0f5a8751845355b7c3271d11f9918a966cb8c9 OS X 10.11.3 Times New Roman Bold Italic.ttf */
182  case HB_CODEPOINT_ENCODE3 (478, 3046, 41902):
183  /* sha1sum:96eda93f7d33e79962451c6c39a6b51ee893ce8c tahoma.ttf from Windows 8 */
184  case HB_CODEPOINT_ENCODE3 (898, 12554, 46470):
185  /* sha1sum:20928dc06014e0cd120b6fc942d0c3b1a46ac2bc tahomabd.ttf from Windows 8 */
186  case HB_CODEPOINT_ENCODE3 (910, 12566, 47732):
187  /* sha1sum:4f95b7e4878f60fa3a39ca269618dfde9721a79e tahoma.ttf from Windows 8.1 */
188  case HB_CODEPOINT_ENCODE3 (928, 23298, 59332):
189  /* sha1sum:6d400781948517c3c0441ba42acb309584b73033 tahomabd.ttf from Windows 8.1 */
190  case HB_CODEPOINT_ENCODE3 (940, 23310, 60732):
191  /* tahoma.ttf v6.04 from Windows 8.1 x64, see https://bugzilla.mozilla.org/show_bug.cgi?id=1279925 */
192  case HB_CODEPOINT_ENCODE3 (964, 23836, 60072):
193  /* tahomabd.ttf v6.04 from Windows 8.1 x64, see https://bugzilla.mozilla.org/show_bug.cgi?id=1279925 */
194  case HB_CODEPOINT_ENCODE3 (976, 23832, 61456):
195  /* sha1sum:e55fa2dfe957a9f7ec26be516a0e30b0c925f846 tahoma.ttf from Windows 10 */
196  case HB_CODEPOINT_ENCODE3 (994, 24474, 60336):
197  /* sha1sum:7199385abb4c2cc81c83a151a7599b6368e92343 tahomabd.ttf from Windows 10 */
198  case HB_CODEPOINT_ENCODE3 (1006, 24470, 61740):
199  /* tahoma.ttf v6.91 from Windows 10 x64, see https://bugzilla.mozilla.org/show_bug.cgi?id=1279925 */
200  case HB_CODEPOINT_ENCODE3 (1006, 24576, 61346):
201  /* tahomabd.ttf v6.91 from Windows 10 x64, see https://bugzilla.mozilla.org/show_bug.cgi?id=1279925 */
202  case HB_CODEPOINT_ENCODE3 (1018, 24572, 62828):
203  /* sha1sum:b9c84d820c49850d3d27ec498be93955b82772b5 tahoma.ttf from Windows 10 AU */
204  case HB_CODEPOINT_ENCODE3 (1006, 24576, 61352):
205  /* sha1sum:2bdfaab28174bdadd2f3d4200a30a7ae31db79d2 tahomabd.ttf from Windows 10 AU */
206  case HB_CODEPOINT_ENCODE3 (1018, 24572, 62834):
207  /* sha1sum:b0d36cf5a2fbe746a3dd277bffc6756a820807a7 Tahoma.ttf from Mac OS X 10.9 */
208  case HB_CODEPOINT_ENCODE3 (832, 7324, 47162):
209  /* sha1sum:12fc4538e84d461771b30c18b5eb6bd434e30fba Tahoma Bold.ttf from Mac OS X 10.9 */
210  case HB_CODEPOINT_ENCODE3 (844, 7302, 45474):
211  /* sha1sum:eb8afadd28e9cf963e886b23a30b44ab4fd83acc himalaya.ttf from Windows 7 */
212  case HB_CODEPOINT_ENCODE3 (180, 13054, 7254):
213  /* sha1sum:73da7f025b238a3f737aa1fde22577a6370f77b0 himalaya.ttf from Windows 8 */
214  case HB_CODEPOINT_ENCODE3 (192, 12638, 7254):
215  /* sha1sum:6e80fd1c0b059bbee49272401583160dc1e6a427 himalaya.ttf from Windows 8.1 */
216  case HB_CODEPOINT_ENCODE3 (192, 12690, 7254):
217  /* 8d9267aea9cd2c852ecfb9f12a6e834bfaeafe44 cantarell-fonts-0.0.21/otf/Cantarell-Regular.otf */
218  /* 983988ff7b47439ab79aeaf9a45bd4a2c5b9d371 cantarell-fonts-0.0.21/otf/Cantarell-Oblique.otf */
219  case HB_CODEPOINT_ENCODE3 (188, 248, 3852):
220  /* 2c0c90c6f6087ffbfea76589c93113a9cbb0e75f cantarell-fonts-0.0.21/otf/Cantarell-Bold.otf */
221  /* 55461f5b853c6da88069ffcdf7f4dd3f8d7e3e6b cantarell-fonts-0.0.21/otf/Cantarell-Bold-Oblique.otf */
222  case HB_CODEPOINT_ENCODE3 (188, 264, 3426):
223  /* d125afa82a77a6475ac0e74e7c207914af84b37a padauk-2.80/Padauk.ttf RHEL 7.2 */
224  case HB_CODEPOINT_ENCODE3 (1058, 47032, 11818):
225  /* 0f7b80437227b90a577cc078c0216160ae61b031 padauk-2.80/Padauk-Bold.ttf RHEL 7.2*/
226  case HB_CODEPOINT_ENCODE3 (1046, 47030, 12600):
227  /* d3dde9aa0a6b7f8f6a89ef1002e9aaa11b882290 padauk-2.80/Padauk.ttf Ubuntu 16.04 */
228  case HB_CODEPOINT_ENCODE3 (1058, 71796, 16770):
229  /* 5f3c98ccccae8a953be2d122c1b3a77fd805093f padauk-2.80/Padauk-Bold.ttf Ubuntu 16.04 */
230  case HB_CODEPOINT_ENCODE3 (1046, 71790, 17862):
231  /* 6c93b63b64e8b2c93f5e824e78caca555dc887c7 padauk-2.80/Padauk-book.ttf */
232  case HB_CODEPOINT_ENCODE3 (1046, 71788, 17112):
233  /* d89b1664058359b8ec82e35d3531931125991fb9 padauk-2.80/Padauk-bookbold.ttf */
234  case HB_CODEPOINT_ENCODE3 (1058, 71794, 17514):
235  /* 824cfd193aaf6234b2b4dc0cf3c6ef576c0d00ef padauk-3.0/Padauk-book.ttf */
236  case HB_CODEPOINT_ENCODE3 (1330, 109904, 57938):
237  /* 91fcc10cf15e012d27571e075b3b4dfe31754a8a padauk-3.0/Padauk-bookbold.ttf */
238  case HB_CODEPOINT_ENCODE3 (1330, 109904, 58972):
239  /* sha1sum: c26e41d567ed821bed997e937bc0c41435689e85 Padauk.ttf
240  * "Padauk Regular" "Version 2.5", see https://crbug.com/681813 */
241  case HB_CODEPOINT_ENCODE3 (1004, 59092, 14836):
242  return true;
243  }
244  return false;
245 }
246 
247 static void
250 {
252 
253  const OT::GDEF &gdef = *font->face->table.GDEF->table;
254  unsigned int count = buffer->len;
255  for (unsigned int i = 0; i < count; i++)
256  {
257  _hb_glyph_info_set_glyph_props (&buffer->info[i], gdef.get_glyph_props (buffer->info[i].codepoint));
259  buffer->info[i].syllable() = 0;
260  }
261 }
262 
263 /* Public API */
264 
265 /**
266  * hb_ot_layout_has_glyph_classes:
267  * @face: #hb_face_t to work upon
268  *
269  * Tests whether a face has any glyph classes defined in its GDEF table.
270  *
271  * Return value: %true if data found, false otherwise
272  *
273  **/
274 hb_bool_t
276 {
277  return face->table.GDEF->table->has_glyph_classes ();
278 }
279 
280 /**
281  * hb_ot_layout_get_glyph_class:
282  * @face: The #hb_face_t to work on
283  * @glyph: The #hb_codepoint_t code point to query
284  *
285  * Fetches the GDEF class of the requested glyph in the specified face.
286  *
287  * Return value: The #hb_ot_layout_glyph_class_t glyph class of the given code
288  * point in the GDEF table of the face.
289  *
290  * Since: 0.9.7
291  **/
295 {
296  return (hb_ot_layout_glyph_class_t) face->table.GDEF->table->get_glyph_class (glyph);
297 }
298 
299 /**
300  * hb_ot_layout_get_glyphs_in_class:
301  * @face: The #hb_face_t to work on
302  * @klass: The #hb_ot_layout_glyph_class_t GDEF class to retrieve
303  * @glyphs: (out): The #hb_set_t set of all glyphs belonging to the requested
304  * class.
305  *
306  * Retrieves the set of all glyphs from the face that belong to the requested
307  * glyph class in the face's GDEF table.
308  *
309  * Since: 0.9.7
310  **/
311 void
314  hb_set_t *glyphs /* OUT */)
315 {
316  return face->table.GDEF->table->get_glyphs_in_class (klass, glyphs);
317 }
318 
319 #ifndef HB_NO_LAYOUT_UNUSED
320 /**
321  * hb_ot_layout_get_attach_points:
322  * @face: The #hb_face_t to work on
323  * @glyph: The #hb_codepoint_t code point to query
324  * @start_offset: offset of the first attachment point to retrieve
325  * @point_count: (inout) (allow-none): Input = the maximum number of attachment points to return;
326  * Output = the actual number of attachment points returned (may be zero)
327  * @point_array: (out) (array length=point_count): The array of attachment points found for the query
328  *
329  * Fetches a list of all attachment points for the specified glyph in the GDEF
330  * table of the face. The list returned will begin at the offset provided.
331  *
332  * Useful if the client program wishes to cache the list.
333  *
334  **/
335 unsigned int
338  unsigned int start_offset,
339  unsigned int *point_count /* IN/OUT */,
340  unsigned int *point_array /* OUT */)
341 {
342  return face->table.GDEF->table->get_attach_points (glyph,
343  start_offset,
344  point_count,
345  point_array);
346 }
347 /**
348  * hb_ot_layout_get_ligature_carets:
349  * @font: The #hb_font_t to work on
350  * @direction: The #hb_direction_t text direction to use
351  * @glyph: The #hb_codepoint_t code point to query
352  * @start_offset: offset of the first caret position to retrieve
353  * @caret_count: (inout) (allow-none): Input = the maximum number of caret positions to return;
354  * Output = the actual number of caret positions returned (may be zero)
355  * @caret_array: (out) (array length=caret_count): The array of caret positions found for the query
356  *
357  * Fetches a list of the caret positions defined for a ligature glyph in the GDEF
358  * table of the font. The list returned will begin at the offset provided.
359  *
360  **/
361 unsigned int
365  unsigned int start_offset,
366  unsigned int *caret_count /* IN/OUT */,
367  hb_position_t *caret_array /* OUT */)
368 {
369  return font->face->table.GDEF->table->get_lig_carets (font, direction, glyph, start_offset, caret_count, caret_array);
370 }
371 #endif
372 
373 
374 /*
375  * GSUB/GPOS
376  */
377 
378 bool
380  hb_face_t *face) const
381 {
382 #ifdef HB_NO_OT_LAYOUT_BLACKLIST
383  return false;
384 #endif
385  return false;
386 }
387 
388 bool
390  hb_face_t *face HB_UNUSED) const
391 {
392 #ifdef HB_NO_OT_LAYOUT_BLACKLIST
393  return false;
394 #endif
395  return false;
396 }
397 
398 static const OT::GSUBGPOS&
400  hb_tag_t table_tag)
401 {
402  switch (table_tag) {
403  case HB_OT_TAG_GSUB: return *face->table.GSUB->table;
404  case HB_OT_TAG_GPOS: return *face->table.GPOS->table;
405  default: return Null (OT::GSUBGPOS);
406  }
407 }
408 
409 
410 /**
411  * hb_ot_layout_table_get_script_tags:
412  * @face: #hb_face_t to work upon
413  * @table_tag: HB_OT_TAG_GSUB or HB_OT_TAG_GPOS
414  * @start_offset: offset of the first script tag to retrieve
415  * @script_count: (inout) (allow-none): Input = the maximum number of script tags to return;
416  * Output = the actual number of script tags returned (may be zero)
417  * @script_tags: (out) (array length=script_count): The array of #hb_tag_t script tags found for the query
418  *
419  * Fetches a list of all scripts enumerated in the specified face's GSUB table
420  * or GPOS table. The list returned will begin at the offset provided.
421  *
422  **/
423 unsigned int
425  hb_tag_t table_tag,
426  unsigned int start_offset,
427  unsigned int *script_count /* IN/OUT */,
428  hb_tag_t *script_tags /* OUT */)
429 {
430  const OT::GSUBGPOS &g = get_gsubgpos_table (face, table_tag);
431 
432  return g.get_script_tags (start_offset, script_count, script_tags);
433 }
434 
435 #define HB_OT_TAG_LATIN_SCRIPT HB_TAG ('l', 'a', 't', 'n')
436 
437 /**
438  * hb_ot_layout_table_find_script:
439  * @face: #hb_face_t to work upon
440  * @table_tag: HB_OT_TAG_GSUB or HB_OT_TAG_GPOS
441  * @script_tag: #hb_tag_t of the script tag requested
442  * @script_index: (out): The index of the requested script tag
443  *
444  * Fetches the index if a given script tag in the specified face's GSUB table
445  * or GPOS table.
446  *
447  * Return value: %true if the script is found, false otherwise
448  *
449  **/
450 hb_bool_t
452  hb_tag_t table_tag,
453  hb_tag_t script_tag,
454  unsigned int *script_index /* OUT */)
455 {
457  const OT::GSUBGPOS &g = get_gsubgpos_table (face, table_tag);
458 
459  if (g.find_script_index (script_tag, script_index))
460  return true;
461 
462  /* try finding 'DFLT' */
463  if (g.find_script_index (HB_OT_TAG_DEFAULT_SCRIPT, script_index))
464  return false;
465 
466  /* try with 'dflt'; MS site has had typos and many fonts use it now :(.
467  * including many versions of DejaVu Sans Mono! */
468  if (g.find_script_index (HB_OT_TAG_DEFAULT_LANGUAGE, script_index))
469  return false;
470 
471  /* try with 'latn'; some old fonts put their features there even though
472  they're really trying to support Thai, for example :( */
473  if (g.find_script_index (HB_OT_TAG_LATIN_SCRIPT, script_index))
474  return false;
475 
476  if (script_index) *script_index = HB_OT_LAYOUT_NO_SCRIPT_INDEX;
477  return false;
478 }
479 
480 #ifndef HB_DISABLE_DEPRECATED
481 /**
482  * hb_ot_layout_table_choose_script:
483  * @face: #hb_face_t to work upon
484  * @table_tag: HB_OT_TAG_GSUB or HB_OT_TAG_GPOS
485  * @script_tags: Array of #hb_tag_t script tags
486  * @script_index: (out): The index of the requested script tag
487  * @chosen_script: (out): #hb_tag_t of the script tag requested
488  *
489  * Deprecated since 2.0.0
490  **/
491 hb_bool_t
493  hb_tag_t table_tag,
494  const hb_tag_t *script_tags,
495  unsigned int *script_index /* OUT */,
496  hb_tag_t *chosen_script /* OUT */)
497 {
498  const hb_tag_t *t;
499  for (t = script_tags; *t; t++);
500  return hb_ot_layout_table_select_script (face, table_tag, t - script_tags, script_tags, script_index, chosen_script);
501 }
502 #endif
503 
504 /**
505  * hb_ot_layout_table_select_script:
506  * @face: #hb_face_t to work upon
507  * @table_tag: HB_OT_TAG_GSUB or HB_OT_TAG_GPOS
508  * @script_count: Number of script tags in the array
509  * @script_tags: Array of #hb_tag_t script tags
510  * @script_index: (out): The index of the requested script
511  * @chosen_script: (out): #hb_tag_t of the requested script
512  *
513  * Since: 2.0.0
514  **/
515 hb_bool_t
517  hb_tag_t table_tag,
518  unsigned int script_count,
519  const hb_tag_t *script_tags,
520  unsigned int *script_index /* OUT */,
521  hb_tag_t *chosen_script /* OUT */)
522 {
524  const OT::GSUBGPOS &g = get_gsubgpos_table (face, table_tag);
525  unsigned int i;
526 
527  for (i = 0; i < script_count; i++)
528  {
529  if (g.find_script_index (script_tags[i], script_index))
530  {
531  if (chosen_script)
532  *chosen_script = script_tags[i];
533  return true;
534  }
535  }
536 
537  /* try finding 'DFLT' */
538  if (g.find_script_index (HB_OT_TAG_DEFAULT_SCRIPT, script_index)) {
539  if (chosen_script)
540  *chosen_script = HB_OT_TAG_DEFAULT_SCRIPT;
541  return false;
542  }
543 
544  /* try with 'dflt'; MS site has had typos and many fonts use it now :( */
545  if (g.find_script_index (HB_OT_TAG_DEFAULT_LANGUAGE, script_index)) {
546  if (chosen_script)
547  *chosen_script = HB_OT_TAG_DEFAULT_LANGUAGE;
548  return false;
549  }
550 
551  /* try with 'latn'; some old fonts put their features there even though
552  they're really trying to support Thai, for example :( */
553  if (g.find_script_index (HB_OT_TAG_LATIN_SCRIPT, script_index)) {
554  if (chosen_script)
555  *chosen_script = HB_OT_TAG_LATIN_SCRIPT;
556  return false;
557  }
558 
559  if (script_index) *script_index = HB_OT_LAYOUT_NO_SCRIPT_INDEX;
560  if (chosen_script)
561  *chosen_script = HB_OT_LAYOUT_NO_SCRIPT_INDEX;
562  return false;
563 }
564 
565 
566 /**
567  * hb_ot_layout_table_get_feature_tags:
568  * @face: #hb_face_t to work upon
569  * @table_tag: HB_OT_TAG_GSUB or HB_OT_TAG_GPOS
570  * @start_offset: offset of the first feature tag to retrieve
571  * @feature_count: (inout) (allow-none): Input = the maximum number of feature tags to return;
572  * Output = the actual number of feature tags returned (may be zero)
573  * @feature_tags: (out) (array length=feature_count): Array of feature tags found in the table
574  *
575  * Fetches a list of all feature tags in the given face's GSUB or GPOS table.
576  *
577  **/
578 unsigned int
580  hb_tag_t table_tag,
581  unsigned int start_offset,
582  unsigned int *feature_count /* IN/OUT */,
583  hb_tag_t *feature_tags /* OUT */)
584 {
585  const OT::GSUBGPOS &g = get_gsubgpos_table (face, table_tag);
586 
587  return g.get_feature_tags (start_offset, feature_count, feature_tags);
588 }
589 
590 
591 /**
592  * hb_ot_layout_table_find_feature:
593  * @face: #hb_face_t to work upon
594  * @table_tag: HB_OT_TAG_GSUB or HB_OT_TAG_GPOS
595  * @feature_tag: The #hb_tag_t og the requested feature tag
596  * @feature_index: (out): The index of the requested feature
597  *
598  * Fetches the index for a given feature tag in the specified face's GSUB table
599  * or GPOS table.
600  *
601  * Return value: %true if the feature is found, false otherwise
602  **/
603 bool
605  hb_tag_t table_tag,
606  hb_tag_t feature_tag,
607  unsigned int *feature_index /* OUT */)
608 {
610  const OT::GSUBGPOS &g = get_gsubgpos_table (face, table_tag);
611 
612  unsigned int num_features = g.get_feature_count ();
613  for (unsigned int i = 0; i < num_features; i++)
614  {
615  if (feature_tag == g.get_feature_tag (i)) {
616  if (feature_index) *feature_index = i;
617  return true;
618  }
619  }
620 
622  return false;
623 }
624 
625 
626 /**
627  * hb_ot_layout_script_get_language_tags:
628  * @face: #hb_face_t to work upon
629  * @table_tag: HB_OT_TAG_GSUB or HB_OT_TAG_GPOS
630  * @script_index: The index of the requested script tag
631  * @start_offset: offset of the first language tag to retrieve
632  * @language_count: (inout) (allow-none): Input = the maximum number of language tags to return;
633  * Output = the actual number of language tags returned (may be zero)
634  * @language_tags: (out) (array length=language_count): Array of language tags found in the table
635  *
636  * Fetches a list of language tags in the given face's GSUB or GPOS table, underneath
637  * the specified script index. The list returned will begin at the offset provided.
638  *
639  **/
640 unsigned int
642  hb_tag_t table_tag,
643  unsigned int script_index,
644  unsigned int start_offset,
645  unsigned int *language_count /* IN/OUT */,
646  hb_tag_t *language_tags /* OUT */)
647 {
648  const OT::Script &s = get_gsubgpos_table (face, table_tag).get_script (script_index);
649 
650  return s.get_lang_sys_tags (start_offset, language_count, language_tags);
651 }
652 
653 
654 #ifndef HB_DISABLE_DEPRECATED
655 /**
656  * hb_ot_layout_script_find_language:
657  * @face: #hb_face_t to work upon
658  * @table_tag: HB_OT_TAG_GSUB or HB_OT_TAG_GPOS
659  * @script_index: The index of the requested script tag
660  * @language_tag: The #hb_tag_t of the requested language
661  * @language_index: The index of the requested language
662  *
663  * Fetches the index of a given language tag in the specified face's GSUB table
664  * or GPOS table, underneath the specified script tag.
665  *
666  * Return value: %true if the language tag is found, false otherwise
667  *
668  * Since: ??
669  * Deprecated: ??
670  **/
671 hb_bool_t
673  hb_tag_t table_tag,
674  unsigned int script_index,
675  hb_tag_t language_tag,
676  unsigned int *language_index)
677 {
679  table_tag,
680  script_index,
681  1,
682  &language_tag,
683  language_index);
684 }
685 #endif
686 
687 
688 /**
689  * hb_ot_layout_script_select_language:
690  * @face: #hb_face_t to work upon
691  * @table_tag: HB_OT_TAG_GSUB or HB_OT_TAG_GPOS
692  * @script_index: The index of the requested script tag
693  * @language_count: The number of languages in the specified script
694  * @language_tags: The array of language tags
695  * @language_index: (out): The index of the requested language
696  *
697  * Fetches the index of a given language tag in the specified face's GSUB table
698  * or GPOS table, underneath the specified script index.
699  *
700  * Return value: %true if the language tag is found, false otherwise
701  *
702  * Since: 2.0.0
703  **/
704 hb_bool_t
706  hb_tag_t table_tag,
707  unsigned int script_index,
708  unsigned int language_count,
709  const hb_tag_t *language_tags,
710  unsigned int *language_index /* OUT */)
711 {
713  const OT::Script &s = get_gsubgpos_table (face, table_tag).get_script (script_index);
714  unsigned int i;
715 
716  for (i = 0; i < language_count; i++)
717  {
718  if (s.find_lang_sys_index (language_tags[i], language_index))
719  return true;
720  }
721 
722  /* try finding 'dflt' */
723  if (s.find_lang_sys_index (HB_OT_TAG_DEFAULT_LANGUAGE, language_index))
724  return false;
725 
726  if (language_index) *language_index = HB_OT_LAYOUT_DEFAULT_LANGUAGE_INDEX;
727  return false;
728 }
729 
730 
731 /**
732  * hb_ot_layout_language_get_required_feature_index:
733  * @face: #hb_face_t to work upon
734  * @table_tag: HB_OT_TAG_GSUB or HB_OT_TAG_GPOS
735  * @script_index: The index of the requested script tag
736  * @language_index: The index of the requested language tag
737  * @feature_index: (out): The index of the requested feature
738  *
739  * Fetches the index of a requested feature in the given face's GSUB or GPOS table,
740  * underneath the specified script and language.
741  *
742  * Return value: %true if the feature is found, false otherwise
743  *
744  **/
745 hb_bool_t
747  hb_tag_t table_tag,
748  unsigned int script_index,
749  unsigned int language_index,
750  unsigned int *feature_index /* OUT */)
751 {
753  table_tag,
754  script_index,
755  language_index,
757  nullptr);
758 }
759 
760 
761 /**
762  * hb_ot_layout_language_get_required_feature:
763  * @face: #hb_face_t to work upon
764  * @table_tag: HB_OT_TAG_GSUB or HB_OT_TAG_GPOS
765  * @script_index: The index of the requested script tag
766  * @language_index: The index of the requested language tag
767  * @feature_index: (out): The index of the requested feature
768  * @feature_tag: (out): The #hb_tag_t of the requested feature
769  *
770  * Fetches the tag of a requested feature index in the given face's GSUB or GPOS table,
771  * underneath the specified script and language.
772  *
773  * Return value: %true if the feature is found, false otherwise
774  *
775  * Since: 0.9.30
776  **/
777 hb_bool_t
779  hb_tag_t table_tag,
780  unsigned int script_index,
781  unsigned int language_index,
782  unsigned int *feature_index /* OUT */,
783  hb_tag_t *feature_tag /* OUT */)
784 {
785  const OT::GSUBGPOS &g = get_gsubgpos_table (face, table_tag);
786  const OT::LangSys &l = g.get_script (script_index).get_lang_sys (language_index);
787 
788  unsigned int index = l.get_required_feature_index ();
790  if (feature_tag) *feature_tag = g.get_feature_tag (index);
791 
792  return l.has_required_feature ();
793 }
794 
795 
796 /**
797  * hb_ot_layout_language_get_feature_indexes:
798  * @face: #hb_face_t to work upon
799  * @table_tag: HB_OT_TAG_GSUB or HB_OT_TAG_GPOS
800  * @script_index: The index of the requested script tag
801  * @language_index: The index of the requested language tag
802  * @start_offset: offset of the first feature tag to retrieve
803  * @feature_count: (inout) (allow-none): Input = the maximum number of feature tags to return;
804  * Output: the actual number of feature tags returned (may be zero)
805  * @feature_indexes: (out) (array length=feature_count): The array of feature indexes found for the query
806  *
807  * Fetches a list of all features in the specified face's GSUB table
808  * or GPOS table, underneath the specified script and language. The list
809  * returned will begin at the offset provided.
810  **/
811 unsigned int
813  hb_tag_t table_tag,
814  unsigned int script_index,
815  unsigned int language_index,
816  unsigned int start_offset,
817  unsigned int *feature_count /* IN/OUT */,
818  unsigned int *feature_indexes /* OUT */)
819 {
820  const OT::GSUBGPOS &g = get_gsubgpos_table (face, table_tag);
821  const OT::LangSys &l = g.get_script (script_index).get_lang_sys (language_index);
822 
823  return l.get_feature_indexes (start_offset, feature_count, feature_indexes);
824 }
825 
826 
827 /**
828  * hb_ot_layout_language_get_feature_tags:
829  * @face: #hb_face_t to work upon
830  * @table_tag: HB_OT_TAG_GSUB or HB_OT_TAG_GPOS
831  * @script_index: The index of the requested script tag
832  * @language_index: The index of the requested language tag
833  * @start_offset: offset of the first feature tag to retrieve
834  * @feature_count: (inout) (allow-none): Input = the maximum number of feature tags to return;
835  * Output = the actual number of feature tags returned (may be zero)
836  * @feature_tags: (out) (array length=feature_count): The array of #hb_tag_t feature tags found for the query
837  *
838  * Fetches a list of all features in the specified face's GSUB table
839  * or GPOS table, underneath the specified script and language. The list
840  * returned will begin at the offset provided.
841  *
842  **/
843 unsigned int
845  hb_tag_t table_tag,
846  unsigned int script_index,
847  unsigned int language_index,
848  unsigned int start_offset,
849  unsigned int *feature_count /* IN/OUT */,
850  hb_tag_t *feature_tags /* OUT */)
851 {
852  const OT::GSUBGPOS &g = get_gsubgpos_table (face, table_tag);
853  const OT::LangSys &l = g.get_script (script_index).get_lang_sys (language_index);
854 
855  static_assert ((sizeof (unsigned int) == sizeof (hb_tag_t)), "");
856  unsigned int ret = l.get_feature_indexes (start_offset, feature_count, (unsigned int *) feature_tags);
857 
858  if (feature_tags) {
859  unsigned int count = *feature_count;
860  for (unsigned int i = 0; i < count; i++)
861  feature_tags[i] = g.get_feature_tag ((unsigned int) feature_tags[i]);
862  }
863 
864  return ret;
865 }
866 
867 
868 /**
869  * hb_ot_layout_language_find_feature:
870  * @face: #hb_face_t to work upon
871  * @table_tag: HB_OT_TAG_GSUB or HB_OT_TAG_GPOS
872  * @script_index: The index of the requested script tag
873  * @language_index: The index of the requested language tag
874  * @feature_tag: #hb_tag_t of the feature tag requested
875  * @feature_index: (out): The index of the requested feature
876  *
877  * Fetches the index of a given feature tag in the specified face's GSUB table
878  * or GPOS table, underneath the specified script and language.
879  *
880  * Return value: %true if the feature is found, false otherwise
881  *
882  **/
883 hb_bool_t
885  hb_tag_t table_tag,
886  unsigned int script_index,
887  unsigned int language_index,
888  hb_tag_t feature_tag,
889  unsigned int *feature_index /* OUT */)
890 {
892  const OT::GSUBGPOS &g = get_gsubgpos_table (face, table_tag);
893  const OT::LangSys &l = g.get_script (script_index).get_lang_sys (language_index);
894 
895  unsigned int num_features = l.get_feature_count ();
896  for (unsigned int i = 0; i < num_features; i++) {
897  unsigned int f_index = l.get_feature_index (i);
898 
899  if (feature_tag == g.get_feature_tag (f_index)) {
900  if (feature_index) *feature_index = f_index;
901  return true;
902  }
903  }
904 
906  return false;
907 }
908 
909 
910 /**
911  * hb_ot_layout_feature_get_lookups:
912  * @face: #hb_face_t to work upon
913  * @table_tag: HB_OT_TAG_GSUB or HB_OT_TAG_GPOS
914  * @feature_index: The index of the requested feature
915  * @start_offset: offset of the first lookup to retrieve
916  * @lookup_count: (inout) (allow-none): Input = the maximum number of lookups to return;
917  * Output = the actual number of lookups returned (may be zero)
918  * @lookup_indexes: (out) (array length=lookup_count): The array of lookup indexes found for the query
919  *
920  * Fetches a list of all lookups enumerated for the specified feature, in
921  * the specified face's GSUB table or GPOS table. The list returned will
922  * begin at the offset provided.
923  *
924  * Since: 0.9.7
925  **/
926 unsigned int
928  hb_tag_t table_tag,
929  unsigned int feature_index,
930  unsigned int start_offset,
931  unsigned int *lookup_count /* IN/OUT */,
932  unsigned int *lookup_indexes /* OUT */)
933 {
935  table_tag,
938  start_offset,
939  lookup_count,
940  lookup_indexes);
941 }
942 
943 
944 /**
945  * hb_ot_layout_table_get_lookup_count:
946  * @face: #hb_face_t to work upon
947  * @table_tag: HB_OT_TAG_GSUB or HB_OT_TAG_GPOS
948  *
949  * Fetches the total number of lookups enumerated in the specified
950  * face's GSUB table or GPOS table.
951  *
952  * Since: 0.9.22
953  **/
954 unsigned int
956  hb_tag_t table_tag)
957 {
958  return get_gsubgpos_table (face, table_tag).get_lookup_count ();
959 }
960 
961 
963 {
965  hb_tag_t table_tag,
966  hb_set_t *feature_indexes_)
967  : g (get_gsubgpos_table (face, table_tag)),
968  feature_indexes (feature_indexes_),
969  script_count (0),langsys_count (0), feature_index_count (0) {}
970 
971  bool visited (const OT::Script &s)
972  {
973  /* We might have Null() object here. Don't want to involve
974  * that in the memoize. So, detect empty objects and return. */
975  if (unlikely (!s.has_default_lang_sys () &&
976  !s.get_lang_sys_count ()))
977  return true;
978 
979  if (script_count++ > HB_MAX_SCRIPTS)
980  return true;
981 
982  return visited (s, visited_script);
983  }
984  bool visited (const OT::LangSys &l)
985  {
986  /* We might have Null() object here. Don't want to involve
987  * that in the memoize. So, detect empty objects and return. */
988  if (unlikely (!l.has_required_feature () &&
989  !l.get_feature_count ()))
990  return true;
991 
992  if (langsys_count++ > HB_MAX_LANGSYS)
993  return true;
994 
995  return visited (l, visited_langsys);
996  }
997 
999  {
1000  feature_index_count += count;
1001  return feature_index_count > HB_MAX_FEATURE_INDICES;
1002  }
1003 
1004  private:
1005  template <typename T>
1006  bool visited (const T &p, hb_set_t &visited_set)
1007  {
1009  if (visited_set.has (delta))
1010  return true;
1011 
1012  visited_set.add (delta);
1013  return false;
1014  }
1015 
1016  public:
1017  const OT::GSUBGPOS &g;
1018  hb_set_t *feature_indexes;
1019 
1020  private:
1021  hb_set_t visited_script;
1022  hb_set_t visited_langsys;
1023  unsigned int script_count;
1024  unsigned int langsys_count;
1025  unsigned int feature_index_count;
1026 };
1027 
1028 static void
1030  const OT::LangSys &l,
1031  const hb_tag_t *features)
1032 {
1033  if (c->visited (l)) return;
1034 
1035  if (!features)
1036  {
1037  /* All features. */
1038  if (l.has_required_feature () && !c->visited_feature_indices (1))
1039  c->feature_indexes->add (l.get_required_feature_index ());
1040 
1041  if (!c->visited_feature_indices (l.featureIndex.len))
1042  l.add_feature_indexes_to (c->feature_indexes);
1043  }
1044  else
1045  {
1046  /* Ugh. Any faster way? */
1047  for (; *features; features++)
1048  {
1049  hb_tag_t feature_tag = *features;
1050  unsigned int num_features = l.get_feature_count ();
1051  for (unsigned int i = 0; i < num_features; i++)
1052  {
1053  unsigned int feature_index = l.get_feature_index (i);
1054 
1055  if (feature_tag == c->g.get_feature_tag (feature_index))
1056  {
1057  c->feature_indexes->add (feature_index);
1058  break;
1059  }
1060  }
1061  }
1062  }
1063 }
1064 
1065 static void
1067  const OT::Script &s,
1068  const hb_tag_t *languages,
1069  const hb_tag_t *features)
1070 {
1071  if (c->visited (s)) return;
1072 
1073  if (!languages)
1074  {
1075  /* All languages. */
1076  if (s.has_default_lang_sys ())
1078  s.get_default_lang_sys (),
1079  features);
1080 
1081  unsigned int count = s.get_lang_sys_count ();
1082  for (unsigned int language_index = 0; language_index < count; language_index++)
1084  s.get_lang_sys (language_index),
1085  features);
1086  }
1087  else
1088  {
1089  for (; *languages; languages++)
1090  {
1091  unsigned int language_index;
1092  if (s.find_lang_sys_index (*languages, &language_index))
1094  s.get_lang_sys (language_index),
1095  features);
1096  }
1097  }
1098 }
1099 
1100 
1101 /**
1102  * hb_ot_layout_collect_features:
1103  * @face: #hb_face_t to work upon
1104  * @table_tag: HB_OT_TAG_GSUB or HB_OT_TAG_GPOS
1105  * @scripts: The array of scripts to collect features for
1106  * @languages: The array of languages to collect features for
1107  * @features: The array of features to collect
1108  * @feature_indexes: (out): The array of feature indexes found for the query
1109  *
1110  * Fetches a list of all feature indexes in the specified face's GSUB table
1111  * or GPOS table, underneath the specified scripts, languages, and features.
1112  * If no list of scripts is provided, all scripts will be queried. If no list
1113  * of languages is provided, all languages will be queried. If no list of
1114  * features is provided, all features will be queried.
1115  *
1116  * Since: 1.8.5
1117  **/
1118 void
1120  hb_tag_t table_tag,
1121  const hb_tag_t *scripts,
1122  const hb_tag_t *languages,
1123  const hb_tag_t *features,
1124  hb_set_t *feature_indexes /* OUT */)
1125 {
1126  hb_collect_features_context_t c (face, table_tag, feature_indexes);
1127  if (!scripts)
1128  {
1129  /* All scripts. */
1130  unsigned int count = c.g.get_script_count ();
1131  for (unsigned int script_index = 0; script_index < count; script_index++)
1133  c.g.get_script (script_index),
1134  languages,
1135  features);
1136  }
1137  else
1138  {
1139  for (; *scripts; scripts++)
1140  {
1141  unsigned int script_index;
1142  if (c.g.find_script_index (*scripts, &script_index))
1144  c.g.get_script (script_index),
1145  languages,
1146  features);
1147  }
1148  }
1149 }
1150 
1151 
1152 /**
1153  * hb_ot_layout_collect_lookups:
1154  * @face: #hb_face_t to work upon
1155  * @table_tag: HB_OT_TAG_GSUB or HB_OT_TAG_GPOS
1156  * @scripts: The array of scripts to collect lookups for
1157  * @languages: The array of languages to collect lookups for
1158  * @features: The array of features to collect lookups for
1159  * @lookup_indexes: (out): The array of lookup indexes found for the query
1160  *
1161  * Fetches a list of all feature-lookup indexes in the specified face's GSUB
1162  * table or GPOS table, underneath the specified scripts, languages, and
1163  * features. If no list of scripts is provided, all scripts will be queried.
1164  * If no list of languages is provided, all languages will be queried. If no
1165  * list of features is provided, all features will be queried.
1166  *
1167  * Since: 0.9.8
1168  **/
1169 void
1171  hb_tag_t table_tag,
1172  const hb_tag_t *scripts,
1173  const hb_tag_t *languages,
1174  const hb_tag_t *features,
1175  hb_set_t *lookup_indexes /* OUT */)
1176 {
1177  const OT::GSUBGPOS &g = get_gsubgpos_table (face, table_tag);
1178 
1179  hb_set_t feature_indexes;
1180  hb_ot_layout_collect_features (face, table_tag, scripts, languages, features, &feature_indexes);
1181 
1183  hb_set_next (&feature_indexes, &feature_index);)
1184  g.get_feature (feature_index).add_lookup_indexes_to (lookup_indexes);
1185 
1186  g.feature_variation_collect_lookups (&feature_indexes, lookup_indexes);
1187 }
1188 
1189 
1190 #ifndef HB_NO_LAYOUT_COLLECT_GLYPHS
1191 /**
1192  * hb_ot_layout_lookup_collect_glyphs:
1193  * @face: #hb_face_t to work upon
1194  * @table_tag: HB_OT_TAG_GSUB or HB_OT_TAG_GPOS
1195  * @lookup_index: The index of the feature lookup to query
1196  * @glyphs_before: (out): Array of glyphs preceding the substitution range
1197  * @glyphs_input: (out): Array of input glyphs that would be substituted by the lookup
1198  * @glyphs_after: (out): Array of glyphs following the substitution range
1199  * @glyphs_output: (out): Array of glyphs that would be the substituted output of the lookup
1200  *
1201  * Fetches a list of all glyphs affected by the specified lookup in the
1202  * specified face's GSUB table or GPOS table.
1203  *
1204  * Since: 0.9.7
1205  **/
1206 void
1208  hb_tag_t table_tag,
1209  unsigned int lookup_index,
1210  hb_set_t *glyphs_before, /* OUT. May be NULL */
1211  hb_set_t *glyphs_input, /* OUT. May be NULL */
1212  hb_set_t *glyphs_after, /* OUT. May be NULL */
1213  hb_set_t *glyphs_output /* OUT. May be NULL */)
1214 {
1216  glyphs_before,
1217  glyphs_input,
1218  glyphs_after,
1219  glyphs_output);
1220 
1221  switch (table_tag)
1222  {
1223  case HB_OT_TAG_GSUB:
1224  {
1225  const OT::SubstLookup& l = face->table.GSUB->table->get_lookup (lookup_index);
1226  l.collect_glyphs (&c);
1227  return;
1228  }
1229  case HB_OT_TAG_GPOS:
1230  {
1231  const OT::PosLookup& l = face->table.GPOS->table->get_lookup (lookup_index);
1232  l.collect_glyphs (&c);
1233  return;
1234  }
1235  }
1236 }
1237 #endif
1238 
1239 
1240 /* Variations support */
1241 
1242 
1243 /**
1244  * hb_ot_layout_table_find_feature_variations:
1245  * @face: #hb_face_t to work upon
1246  * @table_tag: HB_OT_TAG_GSUB or HB_OT_TAG_GPOS
1247  * @coords: The variation coordinates to query
1248  * @num_coords: The number of variation coordinates
1249  * @variations_index: (out): The array of feature variations found for the query
1250  *
1251  * Fetches a list of feature variations in the specified face's GSUB table
1252  * or GPOS table, at the specified variation coordinates.
1253  *
1254  **/
1255 hb_bool_t
1257  hb_tag_t table_tag,
1258  const int *coords,
1259  unsigned int num_coords,
1260  unsigned int *variations_index /* out */)
1261 {
1262  const OT::GSUBGPOS &g = get_gsubgpos_table (face, table_tag);
1263 
1264  return g.find_variations_index (coords, num_coords, variations_index);
1265 }
1266 
1267 
1268 /**
1269  * hb_ot_layout_feature_with_variations_get_lookups:
1270  * @face: #hb_face_t to work upon
1271  * @table_tag: HB_OT_TAG_GSUB or HB_OT_TAG_GPOS
1272  * @feature_index: The index of the feature to query
1273  * @variations_index: The index of the feature variation to query
1274  * @start_offset: offset of the first lookup to retrieve
1275  * @lookup_count: (inout) (allow-none): Input = the maximum number of lookups to return;
1276  * Output = the actual number of lookups returned (may be zero)
1277  * @lookup_indexes: (out) (array length=lookup_count): The array of lookups found for the query
1278  *
1279  * Fetches a list of all lookups enumerated for the specified feature, in
1280  * the specified face's GSUB table or GPOS table, enabled at the specified
1281  * variations index. The list returned will begin at the offset provided.
1282  *
1283  **/
1284 unsigned int
1286  hb_tag_t table_tag,
1287  unsigned int feature_index,
1288  unsigned int variations_index,
1289  unsigned int start_offset,
1290  unsigned int *lookup_count /* IN/OUT */,
1291  unsigned int *lookup_indexes /* OUT */)
1292 {
1294  const OT::GSUBGPOS &g = get_gsubgpos_table (face, table_tag);
1295 
1296  const OT::Feature &f = g.get_feature_variation (feature_index, variations_index);
1297 
1298  return f.get_lookup_indexes (start_offset, lookup_count, lookup_indexes);
1299 }
1300 
1301 
1302 /*
1303  * OT::GSUB
1304  */
1305 
1306 
1307 /**
1308  * hb_ot_layout_has_substitution:
1309  * @face: #hb_face_t to work upon
1310  *
1311  * Tests whether the specified face includes any GSUB substitutions.
1312  *
1313  * Return value: %true if data found, false otherwise
1314  *
1315  **/
1316 hb_bool_t
1318 {
1319  return face->table.GSUB->table->has_data ();
1320 }
1321 
1322 
1323 /**
1324  * hb_ot_layout_lookup_would_substitute:
1325  * @face: #hb_face_t to work upon
1326  * @lookup_index: The index of the lookup to query
1327  * @glyphs: The sequence of glyphs to query for substitution
1328  * @glyphs_length: The length of the glyph sequence
1329  * @zero_context: #hb_bool_t indicating whether substitutions should be context-free
1330  *
1331  * Tests whether a specified lookup in the specified face would
1332  * trigger a substitution on the given glyph sequence.
1333  *
1334  * Return value: %true if a substitution would be triggered, false otherwise
1335  *
1336  * Since: 0.9.7
1337  **/
1338 hb_bool_t
1340  unsigned int lookup_index,
1341  const hb_codepoint_t *glyphs,
1342  unsigned int glyphs_length,
1343  hb_bool_t zero_context)
1344 {
1345  if (unlikely (lookup_index >= face->table.GSUB->lookup_count)) return false;
1346  OT::hb_would_apply_context_t c (face, glyphs, glyphs_length, (bool) zero_context);
1347 
1348  const OT::SubstLookup& l = face->table.GSUB->table->get_lookup (lookup_index);
1349  return l.would_apply (&c, &face->table.GSUB->accels[lookup_index]);
1350 }
1351 
1352 
1353 /**
1354  * hb_ot_layout_substitute_start:
1355  * @font: #hb_font_t to use
1356  * @buffer: #hb_buffer_t buffer to work upon
1357  *
1358  * Called before substitution lookups are performed, to ensure that glyph
1359  * class and other properties are set on the glyphs in the buffer.
1360  *
1361  **/
1362 void
1365 {
1367 }
1368 
1369 void
1371  bool (*filter) (const hb_glyph_info_t *info))
1372 {
1373  /* Merge clusters and delete filtered glyphs.
1374  * NOTE! We can't use out-buffer as we have positioning data. */
1375  unsigned int j = 0;
1376  unsigned int count = buffer->len;
1377  hb_glyph_info_t *info = buffer->info;
1378  hb_glyph_position_t *pos = buffer->pos;
1379  for (unsigned int i = 0; i < count; i++)
1380  {
1381  if (filter (&info[i]))
1382  {
1383  /* Merge clusters.
1384  * Same logic as buffer->delete_glyph(), but for in-place removal. */
1385 
1386  unsigned int cluster = info[i].cluster;
1387  if (i + 1 < count && cluster == info[i + 1].cluster)
1388  continue; /* Cluster survives; do nothing. */
1389 
1390  if (j)
1391  {
1392  /* Merge cluster backward. */
1393  if (cluster < info[j - 1].cluster)
1394  {
1395  unsigned int mask = info[i].mask;
1396  unsigned int old_cluster = info[j - 1].cluster;
1397  for (unsigned k = j; k && info[k - 1].cluster == old_cluster; k--)
1398  buffer->set_cluster (info[k - 1], cluster, mask);
1399  }
1400  continue;
1401  }
1402 
1403  if (i + 1 < count)
1404  buffer->merge_clusters (i, i + 2); /* Merge cluster forward. */
1405 
1406  continue;
1407  }
1408 
1409  if (j != i)
1410  {
1411  info[j] = info[i];
1412  pos[j] = pos[i];
1413  }
1414  j++;
1415  }
1416  buffer->len = j;
1417 }
1418 
1419 /**
1420  * hb_ot_layout_lookup_substitute_closure:
1421  * @face: #hb_face_t to work upon
1422  * @lookup_index: index of the feature lookup to query
1423  * @glyphs: (out): Array of glyphs comprising the transitive closure of the lookup
1424  *
1425  * Compute the transitive closure of glyphs needed for a
1426  * specified lookup.
1427  *
1428  * Since: 0.9.7
1429  **/
1430 void
1432  unsigned int lookup_index,
1433  hb_set_t *glyphs /* OUT */)
1434 {
1435  hb_map_t done_lookups;
1436  OT::hb_closure_context_t c (face, glyphs, &done_lookups);
1437 
1438  const OT::SubstLookup& l = face->table.GSUB->table->get_lookup (lookup_index);
1439 
1440  l.closure (&c, lookup_index);
1441 }
1442 
1443 /**
1444  * hb_ot_layout_lookups_substitute_closure:
1445  * @face: #hb_face_t to work upon
1446  * @lookups: The set of lookups to query
1447  * @glyphs: (out): Array of glyphs comprising the transitive closure of the lookups
1448  *
1449  * Compute the transitive closure of glyphs needed for all of the
1450  * provided lookups.
1451  *
1452  * Since: 1.8.1
1453  **/
1454 void
1456  const hb_set_t *lookups,
1457  hb_set_t *glyphs /* OUT */)
1458 {
1459  hb_map_t done_lookups;
1460  OT::hb_closure_context_t c (face, glyphs, &done_lookups);
1461  const OT::GSUB& gsub = *face->table.GSUB->table;
1462 
1463  unsigned int iteration_count = 0;
1464  unsigned int glyphs_length;
1465  do
1466  {
1467  glyphs_length = glyphs->get_population ();
1468  if (lookups)
1469  {
1470  for (hb_codepoint_t lookup_index = HB_SET_VALUE_INVALID; hb_set_next (lookups, &lookup_index);)
1471  gsub.get_lookup (lookup_index).closure (&c, lookup_index);
1472  }
1473  else
1474  {
1475  for (unsigned int i = 0; i < gsub.get_lookup_count (); i++)
1476  gsub.get_lookup (i).closure (&c, i);
1477  }
1478  } while (iteration_count++ <= HB_CLOSURE_MAX_STAGES &&
1479  glyphs_length != glyphs->get_population ());
1480 }
1481 
1482 /*
1483  * OT::GPOS
1484  */
1485 
1486 
1487 /**
1488  * hb_ot_layout_has_positioning:
1489  * @face: #hb_face_t to work upon
1490  *
1491  * Return value: %true if the face has GPOS data, false otherwise
1492  *
1493  **/
1494 hb_bool_t
1496 {
1497  return face->table.GPOS->table->has_data ();
1498 }
1499 
1500 /**
1501  * hb_ot_layout_position_start:
1502  * @font: #hb_font_t to use
1503  * @buffer: #hb_buffer_t buffer to work upon
1504  *
1505  * Called before positioning lookups are performed, to ensure that glyph
1506  * attachment types and glyph-attachment chains are set for the glyphs in the buffer.
1507  *
1508  **/
1509 void
1511 {
1513 }
1514 
1515 
1516 /**
1517  * hb_ot_layout_position_finish_advances:
1518  * @font: #hb_font_t to use
1519  * @buffer: #hb_buffer_t buffer to work upon
1520  *
1521  * Called after positioning lookups are performed, to finish glyph advances.
1522  *
1523  **/
1524 void
1526 {
1528 }
1529 
1530 /**
1531  * hb_ot_layout_position_finish_offsets:
1532  * @font: #hb_font_t to use
1533  * @buffer: #hb_buffer_t buffer to work upon
1534  *
1535  * Called after positioning lookups are performed, to finish glyph offsets.
1536  *
1537  **/
1538 void
1540 {
1542 }
1543 
1544 
1545 #ifndef HB_NO_LAYOUT_FEATURE_PARAMS
1546 /**
1547  * hb_ot_layout_get_size_params:
1548  * @face: #hb_face_t to work upon
1549  * @design_size: (out): The design size of the face
1550  * @subfamily_id: (out): The identifier of the face within the font subfamily
1551  * @subfamily_name_id: (out): The ‘name’ table name ID of the face within the font subfamily
1552  * @range_start: (out): The minimum size of the recommended size range for the face
1553  * @range_end: (out): The maximum size of the recommended size range for the face
1554  *
1555  * Fetches optical-size feature data (i.e., the `size` feature from GPOS). Note that
1556  * the subfamily_id and the subfamily name string (accessible via the subfamily_name_id)
1557  * as used here are defined as pertaining only to fonts within a font family that differ
1558  * specifically in their respective size ranges; other ways to differentiate fonts within
1559  * a subfamily are not covered by the `size` feature.
1560  *
1561  * For more information on this distinction, see the [`size` feature documentation](
1562  * https://docs.microsoft.com/en-us/typography/opentype/spec/features_pt#tag-size).
1563  *
1564  * Return value: %true if data found, false otherwise
1565  *
1566  * Since: 0.9.10
1567  **/
1568 hb_bool_t
1570  unsigned int *design_size, /* OUT. May be NULL */
1571  unsigned int *subfamily_id, /* OUT. May be NULL */
1572  hb_ot_name_id_t *subfamily_name_id, /* OUT. May be NULL */
1573  unsigned int *range_start, /* OUT. May be NULL */
1574  unsigned int *range_end /* OUT. May be NULL */)
1575 {
1576  const OT::GPOS &gpos = *face->table.GPOS->table;
1577  const hb_tag_t tag = HB_TAG ('s','i','z','e');
1578 
1579  unsigned int num_features = gpos.get_feature_count ();
1580  for (unsigned int i = 0; i < num_features; i++)
1581  {
1582  if (tag == gpos.get_feature_tag (i))
1583  {
1584  const OT::Feature &f = gpos.get_feature (i);
1585  const OT::FeatureParamsSize &params = f.get_feature_params ().get_size_params (tag);
1586 
1587  if (params.designSize)
1588  {
1589  if (design_size) *design_size = params.designSize;
1590  if (subfamily_id) *subfamily_id = params.subfamilyID;
1591  if (subfamily_name_id) *subfamily_name_id = params.subfamilyNameID;
1592  if (range_start) *range_start = params.rangeStart;
1593  if (range_end) *range_end = params.rangeEnd;
1594 
1595  return true;
1596  }
1597  }
1598  }
1599 
1600  if (design_size) *design_size = 0;
1601  if (subfamily_id) *subfamily_id = 0;
1602  if (subfamily_name_id) *subfamily_name_id = HB_OT_NAME_ID_INVALID;
1603  if (range_start) *range_start = 0;
1604  if (range_end) *range_end = 0;
1605 
1606  return false;
1607 }
1608 /**
1609  * hb_ot_layout_feature_get_name_ids:
1610  * @face: #hb_face_t to work upon
1611  * @table_tag: table tag to query, "GSUB" or "GPOS".
1612  * @feature_index: index of feature to query.
1613  * @label_id: (out) (allow-none): The ‘name’ table name ID that specifies a string
1614  * for a user-interface label for this feature. (May be NULL.)
1615  * @tooltip_id: (out) (allow-none): The ‘name’ table name ID that specifies a string
1616  * that an application can use for tooltip text for this
1617  * feature. (May be NULL.)
1618  * @sample_id: (out) (allow-none): The ‘name’ table name ID that specifies sample text
1619  * that illustrates the effect of this feature. (May be NULL.)
1620  * @num_named_parameters: (out) (allow-none): Number of named parameters. (May be zero.)
1621  * @first_param_id: (out) (allow-none): The first ‘name’ table name ID used to specify
1622  * strings for user-interface labels for the feature
1623  * parameters. (Must be zero if numParameters is zero.)
1624  *
1625  * Fetches name indices from feature parameters for "Stylistic Set" ('ssXX') or
1626  * "Character Variant" ('cvXX') features.
1627  *
1628  * Return value: %true if data found, false otherwise
1629  *
1630  * Since: 2.0.0
1631  **/
1632 hb_bool_t
1634  hb_tag_t table_tag,
1635  unsigned int feature_index,
1636  hb_ot_name_id_t *label_id, /* OUT. May be NULL */
1637  hb_ot_name_id_t *tooltip_id, /* OUT. May be NULL */
1638  hb_ot_name_id_t *sample_id, /* OUT. May be NULL */
1639  unsigned int *num_named_parameters, /* OUT. May be NULL */
1640  hb_ot_name_id_t *first_param_id /* OUT. May be NULL */)
1641 {
1642  const OT::GSUBGPOS &g = get_gsubgpos_table (face, table_tag);
1643 
1644  hb_tag_t feature_tag = g.get_feature_tag (feature_index);
1645  const OT::Feature &f = g.get_feature (feature_index);
1646 
1647  const OT::FeatureParams &feature_params = f.get_feature_params ();
1648  if (&feature_params != &Null (OT::FeatureParams))
1649  {
1650  const OT::FeatureParamsStylisticSet& ss_params =
1651  feature_params.get_stylistic_set_params (feature_tag);
1652  if (&ss_params != &Null (OT::FeatureParamsStylisticSet)) /* ssXX */
1653  {
1654  if (label_id) *label_id = ss_params.uiNameID;
1655  // ssXX features don't have the rest
1656  if (tooltip_id) *tooltip_id = HB_OT_NAME_ID_INVALID;
1657  if (sample_id) *sample_id = HB_OT_NAME_ID_INVALID;
1658  if (num_named_parameters) *num_named_parameters = 0;
1659  if (first_param_id) *first_param_id = HB_OT_NAME_ID_INVALID;
1660  return true;
1661  }
1662  const OT::FeatureParamsCharacterVariants& cv_params =
1663  feature_params.get_character_variants_params (feature_tag);
1664  if (&cv_params != &Null (OT::FeatureParamsCharacterVariants)) /* cvXX */
1665  {
1666  if (label_id) *label_id = cv_params.featUILableNameID;
1667  if (tooltip_id) *tooltip_id = cv_params.featUITooltipTextNameID;
1668  if (sample_id) *sample_id = cv_params.sampleTextNameID;
1669  if (num_named_parameters) *num_named_parameters = cv_params.numNamedParameters;
1670  if (first_param_id) *first_param_id = cv_params.firstParamUILabelNameID;
1671  return true;
1672  }
1673  }
1674 
1675  if (label_id) *label_id = HB_OT_NAME_ID_INVALID;
1676  if (tooltip_id) *tooltip_id = HB_OT_NAME_ID_INVALID;
1677  if (sample_id) *sample_id = HB_OT_NAME_ID_INVALID;
1678  if (num_named_parameters) *num_named_parameters = 0;
1679  if (first_param_id) *first_param_id = HB_OT_NAME_ID_INVALID;
1680  return false;
1681 }
1682 /**
1683  * hb_ot_layout_feature_get_characters:
1684  * @face: #hb_face_t to work upon
1685  * @table_tag: table tag to query, "GSUB" or "GPOS".
1686  * @feature_index: index of feature to query.
1687  * @start_offset: offset of the first character to retrieve
1688  * @char_count: (inout) (allow-none): Input = the maximum number of characters to return;
1689  * Output = the actual number of characters returned (may be zero)
1690  * @characters: (out caller-allocates) (array length=char_count): A buffer pointer.
1691  * The Unicode codepoints of the characters for which this feature provides
1692  * glyph variants.
1693  *
1694  * Fetches a list of the characters defined as having a variant under the specified
1695  * "Character Variant" ("cvXX") feature tag.
1696  *
1697  * Return value: Number of total sample characters in the cvXX feature.
1698  *
1699  * Since: 2.0.0
1700  **/
1701 unsigned int
1703  hb_tag_t table_tag,
1704  unsigned int feature_index,
1705  unsigned int start_offset,
1706  unsigned int *char_count, /* IN/OUT. May be NULL */
1707  hb_codepoint_t *characters /* OUT. May be NULL */)
1708 {
1709  const OT::GSUBGPOS &g = get_gsubgpos_table (face, table_tag);
1710  return g.get_feature (feature_index)
1711  .get_feature_params ()
1712  .get_character_variants_params(g.get_feature_tag (feature_index))
1713  .get_characters (start_offset, char_count, characters);
1714 }
1715 #endif
1716 
1717 
1718 /*
1719  * Parts of different types are implemented here such that they have direct
1720  * access to GSUB/GPOS lookups.
1721  */
1722 
1723 
1724 struct GSUBProxy
1725 {
1726  static constexpr unsigned table_index = 0u;
1727  static constexpr bool inplace = false;
1729 
1731  table (*face->table.GSUB->table),
1732  accels (face->table.GSUB->accels) {}
1733 
1734  const OT::GSUB &table;
1736 };
1737 
1738 struct GPOSProxy
1739 {
1740  static constexpr unsigned table_index = 1u;
1741  static constexpr bool inplace = true;
1743 
1745  table (*face->table.GPOS->table),
1746  accels (face->table.GPOS->accels) {}
1747 
1748  const OT::GPOS &table;
1750 };
1751 
1752 
1753 static inline bool
1756 {
1757  bool ret = false;
1758  hb_buffer_t *buffer = c->buffer;
1759  while (buffer->idx < buffer->len && buffer->successful)
1760  {
1761  bool applied = false;
1762  if (accel.may_have (buffer->cur().codepoint) &&
1763  (buffer->cur().mask & c->lookup_mask) &&
1764  c->check_glyph_property (&buffer->cur(), c->lookup_props))
1765  {
1766  applied = accel.apply (c);
1767  }
1768 
1769  if (applied)
1770  ret = true;
1771  else
1772  buffer->next_glyph ();
1773  }
1774  return ret;
1775 }
1776 
1777 static inline bool
1780 {
1781  bool ret = false;
1782  hb_buffer_t *buffer = c->buffer;
1783  do
1784  {
1785  if (accel.may_have (buffer->cur().codepoint) &&
1786  (buffer->cur().mask & c->lookup_mask) &&
1787  c->check_glyph_property (&buffer->cur(), c->lookup_props))
1788  ret |= accel.apply (c);
1789 
1790  /* The reverse lookup doesn't "advance" cursor (for good reason). */
1791  buffer->idx--;
1792 
1793  }
1794  while ((int) buffer->idx >= 0);
1795  return ret;
1796 }
1797 
1798 template <typename Proxy>
1799 static inline void
1801  const typename Proxy::Lookup &lookup,
1803 {
1804  hb_buffer_t *buffer = c->buffer;
1805 
1806  if (unlikely (!buffer->len || !c->lookup_mask))
1807  return;
1808 
1809  c->set_lookup_props (lookup.get_props ());
1810 
1811  if (likely (!lookup.is_reverse ()))
1812  {
1813  /* in/out forward substitution/positioning */
1814  if (Proxy::table_index == 0u)
1815  buffer->clear_output ();
1816  buffer->idx = 0;
1817 
1818  bool ret;
1819  ret = apply_forward (c, accel);
1820  if (ret)
1821  {
1822  if (!Proxy::inplace)
1823  buffer->swap_buffers ();
1824  else
1825  assert (!buffer->has_separate_output ());
1826  }
1827  }
1828  else
1829  {
1830  /* in-place backward substitution/positioning */
1831  if (Proxy::table_index == 0u)
1832  buffer->remove_output ();
1833  buffer->idx = buffer->len - 1;
1834 
1835  apply_backward (c, accel);
1836  }
1837 }
1838 
1839 template <typename Proxy>
1840 inline void hb_ot_map_t::apply (const Proxy &proxy,
1841  const hb_ot_shape_plan_t *plan,
1842  hb_font_t *font,
1843  hb_buffer_t *buffer) const
1844 {
1845  const unsigned int table_index = proxy.table_index;
1846  unsigned int i = 0;
1847  OT::hb_ot_apply_context_t c (table_index, font, buffer);
1848  c.set_recurse_func (Proxy::Lookup::apply_recurse_func);
1849 
1850  for (unsigned int stage_index = 0; stage_index < stages[table_index].length; stage_index++) {
1851  const stage_map_t *stage = &stages[table_index][stage_index];
1852  for (; i < stage->last_lookup; i++)
1853  {
1854  unsigned int lookup_index = lookups[table_index][i].index;
1855  if (!buffer->message (font, "start lookup %d", lookup_index)) continue;
1856  c.set_lookup_index (lookup_index);
1857  c.set_lookup_mask (lookups[table_index][i].mask);
1858  c.set_auto_zwj (lookups[table_index][i].auto_zwj);
1859  c.set_auto_zwnj (lookups[table_index][i].auto_zwnj);
1860  if (lookups[table_index][i].random)
1861  {
1862  c.set_random (true);
1863  buffer->unsafe_to_break_all ();
1864  }
1865  apply_string<Proxy> (&c,
1866  proxy.table.get_lookup (lookup_index),
1867  proxy.accels[lookup_index]);
1868  (void) buffer->message (font, "end lookup %d", lookup_index);
1869  }
1870 
1871  if (stage->pause_func)
1872  {
1873  buffer->clear_output ();
1874  stage->pause_func (plan, font, buffer);
1875  }
1876  }
1877 }
1878 
1880 {
1881  GSUBProxy proxy (font->face);
1882  if (!buffer->message (font, "start table GSUB")) return;
1883  apply (proxy, plan, font, buffer);
1884  (void) buffer->message (font, "end table GSUB");
1885 }
1886 
1888 {
1889  GPOSProxy proxy (font->face);
1890  if (!buffer->message (font, "start table GPOS")) return;
1891  apply (proxy, plan, font, buffer);
1892  (void) buffer->message (font, "end table GPOS");
1893 }
1894 
1895 void
1897  const OT::SubstLookup &lookup,
1899 {
1900  apply_string<GSUBProxy> (c, lookup, accel);
1901 }
1902 
1903 #ifndef HB_NO_BASE
1904 /**
1905  * hb_ot_layout_get_baseline:
1906  * @font: a font
1907  * @baseline_tag: a baseline tag
1908  * @direction: text direction.
1909  * @script_tag: script tag.
1910  * @language_tag: language tag.
1911  * @coord: (out): baseline value if found.
1912  *
1913  * Fetches a baseline value from the face.
1914  *
1915  * Return value: if found baseline value in the font.
1916  *
1917  * Since: 2.6.0
1918  **/
1919 hb_bool_t
1921  hb_ot_layout_baseline_tag_t baseline_tag,
1923  hb_tag_t script_tag,
1924  hb_tag_t language_tag,
1925  hb_position_t *coord /* OUT. May be NULL. */)
1926 {
1927  bool result = font->face->table.BASE->get_baseline (font, baseline_tag, direction, script_tag, language_tag, coord);
1928 
1929  if (result && coord)
1930  *coord = HB_DIRECTION_IS_HORIZONTAL (direction) ? font->em_scale_y (*coord) : font->em_scale_x (*coord);
1931 
1932  return result;
1933 }
1934 #endif
1935 
1936 
1938  hb_dispatch_context_t<hb_get_glyph_alternates_dispatch_t, unsigned>
1939 {
1940  static return_t default_return_value () { return 0; }
1941  bool stop_sublookup_iteration (return_t r) const { return r; }
1942 
1943  hb_face_t *face;
1944 
1946  face (face) {}
1947 
1948  private:
1949  template <typename T, typename ...Ts> auto
1950  _dispatch (const T &obj, hb_priority<1>, Ts&&... ds) HB_AUTO_RETURN
1951  ( obj.get_glyph_alternates (hb_forward<Ts> (ds)...) )
1952  template <typename T, typename ...Ts> auto
1953  _dispatch (const T &obj, hb_priority<0>, Ts&&... ds) HB_AUTO_RETURN
1954  ( default_return_value () )
1955  public:
1956  template <typename T, typename ...Ts> auto
1957  dispatch (const T &obj, Ts&&... ds) HB_AUTO_RETURN
1958  ( _dispatch (obj, hb_prioritize, hb_forward<Ts> (ds)...) )
1959 };
1960 
1961 /**
1962  * hb_ot_layout_lookup_get_glyph_alternates:
1963  * @face: a face.
1964  * @lookup_index: index of the feature lookup to query.
1965  * @glyph: a glyph id.
1966  * @start_offset: starting offset.
1967  * @alternate_count: (inout) (allow-none): Input = the maximum number of alternate glyphs to return;
1968  * Output = the actual number of alternate glyphs returned (may be zero).
1969  * @alternate_glyphs: (out caller-allocates) (array length=alternate_count): A glyphs buffer.
1970  * Alternate glyphs associated with the glyph id.
1971  *
1972  * Fetches alternates of a glyph from a given GSUB lookup index.
1973  *
1974  * Return value: total number of alternates found in the specific lookup index for the given glyph id.
1975  *
1976  * Since: 2.6.8
1977  **/
1978 HB_EXTERN unsigned
1980  unsigned lookup_index,
1982  unsigned start_offset,
1983  unsigned *alternate_count /* IN/OUT. May be NULL. */,
1984  hb_codepoint_t *alternate_glyphs /* OUT. May be NULL. */)
1985 {
1987  const OT::SubstLookup &lookup = face->table.GSUB->table->get_lookup (lookup_index);
1988  auto ret = lookup.dispatch (&c, glyph, start_offset, alternate_count, alternate_glyphs);
1989  if (!ret && alternate_count) *alternate_count = 0;
1990  return ret;
1991 }
1992 
1993 #endif
union Lookup Lookup
struct @88 table[500]
#define count(a)
Definition: aptex-macros.h:781
#define static_assert(c, msg)
Definition: cff.cc:31
static uint32_t dispatch(codegen_scope *s, uint32_t pos0)
Definition: codegen.c:536
#define typename
Definition: cppcomp.h:112
int params
Definition: definitions.c:42
void glyphs(int opcode)
Definition: disdvi.c:775
#define info
Definition: dviinfo.c:42
static int feature_index(lua_State *L)
Definition: feature.c:34
#define T
Definition: fmt.h:20
static void
Definition: fpif.c:118
mpz_t * f
Definition: gen-fib.c:34
#define s
Definition: afcover.h:80
#define t
Definition: afcover.h:96
#define c(n)
Definition: gpos-common.c:150
assert(pcxLoadImage24((char *)((void *) 0), fp, pinfo, hdr))
#define likely(x)
Definition: jbig2arith.cc:115
#define unlikely(x)
Definition: jbig2arith.cc:116
small capitals from c petite p scientific f u
Definition: afcover.h:88
small capitals from c petite p
Definition: afcover.h:72
small capitals from c petite p scientific i
Definition: afcover.h:80
FT_Face face
Definition: cffdrivr.c:659
#define const
Definition: ftzconf.h:91
#define true
Definition: ftrandom.c:51
unsigned int uintptr_t
Definition: stdint.h:119
static int ret
Definition: convert.c:72
const int * pos
Definition: combiners.h:905
#define design_size
Definition: mfluac.c:339
static const Mapping features[]
Definition: otfdescrip.cc:537
static const Mapping languages[]
Definition: otfdescrip.cc:141
int k
Definition: otp-parser.c:70
static int delta
Definition: pbmtolj.c:36
static char * stage
Definition: picttoppm.c:111
#define index(s, c)
Definition: plain2.h:351
static int filter
Definition: pnmtopng.c:113
int g
Definition: ppmqvga.c:68
int r
Definition: ppmqvga.c:68
static int cluster
Definition: ppmtopjxl.c:40
#define HB_CODEPOINT_ENCODE3(x, y, z)
Definition: hb-algs.hh:40
uint32_t hb_codepoint_t
Definition: hb-common.h:106
#define HB_TAG(c1, c2, c3, c4)
Definition: hb-common.h:155
int32_t hb_position_t
Definition: hb-common.h:115
int hb_bool_t
Definition: hb-common.h:97
uint32_t hb_tag_t
Definition: hb-common.h:147
hb_direction_t
Definition: hb-common.h:193
#define HB_DIRECTION_IS_HORIZONTAL(dir)
Definition: hb-common.h:225
#define HB_EXTERN
Definition: hb-common.h:37
#define hb_prioritize
Definition: hb-meta.hh:73
#define HB_AUTO_RETURN(E)
Definition: hb-meta.hh:68
static constexpr T && hb_forward(hb_remove_reference< T > &t)
Definition: hb-meta.hh:177
#define Null(Type)
Definition: hb-null.hh:94
#define HB_MAX_LANGSYS
#define HB_CLOSURE_MAX_STAGES
#define HB_MAX_SCRIPTS
#define HB_MAX_FEATURE_INDICES
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, hb_codepoint_t *alternate_glyphs)
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, hb_tag_t *language_tags)
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, hb_tag_t *feature_tag)
bool hb_ot_layout_has_kerning(hb_face_t *face)
Definition: hb-ot-layout.cc:83
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, hb_tag_t *feature_tags)
bool hb_ot_layout_has_machine_kerning(hb_face_t *face)
Definition: hb-ot-layout.cc:99
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)
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, unsigned int *lookup_indexes)
void hb_ot_layout_position_finish_offsets(hb_font_t *font, hb_buffer_t *buffer)
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, hb_codepoint_t *characters)
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)
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_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)
hb_ot_layout_glyph_class_t hb_ot_layout_get_glyph_class(hb_face_t *face, hb_codepoint_t glyph)
void hb_ot_layout_substitute_lookup(OT::hb_ot_apply_context_t *c, const OT::SubstLookup &lookup, const OT::hb_ot_layout_lookup_accelerator_t &accel)
hb_bool_t hb_ot_layout_get_size_params(hb_face_t *face, unsigned int *design_size, unsigned int *subfamily_id, hb_ot_name_id_t *subfamily_name_id, unsigned int *range_start, unsigned int *range_end)
unsigned int hb_ot_layout_table_get_lookup_count(hb_face_t *face, hb_tag_t table_tag)
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)
void hb_ot_layout_position_finish_advances(hb_font_t *font, hb_buffer_t *buffer)
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, hb_ot_name_id_t *tooltip_id, hb_ot_name_id_t *sample_id, unsigned int *num_named_parameters, hb_ot_name_id_t *first_param_id)
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)
void hb_ot_layout_get_glyphs_in_class(hb_face_t *face, hb_ot_layout_glyph_class_t klass, hb_set_t *glyphs)
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, hb_set_t *glyphs_input, hb_set_t *glyphs_after, hb_set_t *glyphs_output)
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, hb_position_t *caret_array)
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, hb_tag_t *feature_tags)
bool hb_ot_layout_has_cross_kerning(hb_face_t *face)
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)
bool hb_ot_layout_table_find_feature(hb_face_t *face, hb_tag_t table_tag, hb_tag_t feature_tag, unsigned int *feature_index)
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, unsigned int *lookup_indexes)
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)
void hb_ot_layout_substitute_start(hb_font_t *font, hb_buffer_t *buffer)
hb_bool_t hb_ot_layout_script_find_language(hb_face_t *face, hb_tag_t table_tag, unsigned int script_index, hb_tag_t language_tag, unsigned int *language_index)
void hb_ot_layout_lookup_substitute_closure(hb_face_t *face, unsigned int lookup_index, hb_set_t *glyphs)
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, hb_tag_t *script_tags)
hb_bool_t hb_ot_layout_has_glyph_classes(hb_face_t *face)
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, hb_tag_t *chosen_script)
hb_bool_t hb_ot_layout_has_positioning(hb_face_t *face)
void hb_ot_layout_kern(const hb_ot_shape_plan_t *plan, hb_font_t *font, hb_buffer_t *buffer)
hb_bool_t hb_ot_layout_has_substitution(hb_face_t *face)
void hb_ot_layout_lookups_substitute_closure(hb_face_t *face, const hb_set_t *lookups, hb_set_t *glyphs)
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, unsigned int *feature_indexes)
void hb_ot_layout_position_start(hb_font_t *font, hb_buffer_t *buffer)
void hb_ot_layout_delete_glyphs_inplace(hb_buffer_t *buffer, bool(*filter)(const hb_glyph_info_t *info))
unsigned int hb_ot_layout_get_attach_points(hb_face_t *face, hb_codepoint_t glyph, unsigned int start_offset, unsigned int *point_count, unsigned int *point_array)
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)
hb_bool_t hb_ot_layout_table_choose_script(hb_face_t *face, hb_tag_t table_tag, const hb_tag_t *script_tags, unsigned int *script_index, hb_tag_t *chosen_script)
#define HB_OT_LAYOUT_NO_SCRIPT_INDEX
Definition: hb-ot-layout.h:147
#define HB_OT_TAG_GPOS
Definition: hb-ot-layout.h:44
hb_ot_layout_glyph_class_t
Definition: hb-ot-layout.h:107
#define HB_OT_LAYOUT_DEFAULT_LANGUAGE_INDEX
Definition: hb-ot-layout.h:149
#define HB_OT_TAG_DEFAULT_LANGUAGE
Definition: hb-ot-layout.h:53
#define HB_OT_TAG_DEFAULT_SCRIPT
Definition: hb-ot-layout.h:52
hb_ot_layout_baseline_tag_t
Definition: hb-ot-layout.h:440
#define HB_OT_TAG_GSUB
Definition: hb-ot-layout.h:43
#define HB_OT_LAYOUT_NO_VARIATIONS_INDEX
Definition: hb-ot-layout.h:150
#define HB_OT_LAYOUT_NO_FEATURE_INDEX
Definition: hb-ot-layout.h:148
static void _hb_glyph_info_set_glyph_props(hb_glyph_info_t *info, unsigned int props)
static void _hb_buffer_assert_gsubgpos_vars(hb_buffer_t *buffer)
static void _hb_glyph_info_clear_lig_props(hb_glyph_info_t *info)
unsigned int hb_ot_name_id_t
Definition: hb-ot-name.h:79
@ HB_OT_NAME_ID_INVALID
Definition: hb-ot-name.h:76
hb_bool_t hb_set_next(const hb_set_t *set, hb_codepoint_t *codepoint)
Definition: hb-set.cc:491
#define HB_SET_VALUE_INVALID
Definition: hb-set.h:42
#define HB_UNUSED
Definition: hb.hh:260
#define mask(n)
Definition: lbitlib.c:93
#define HB_OT_TAG_LATIN_SCRIPT
static void langsys_collect_features(hb_collect_features_context_t *c, const OT::LangSys &l, const hb_tag_t *features)
static void _hb_ot_layout_set_glyph_props(hb_font_t *font, hb_buffer_t *buffer)
static bool apply_backward(OT::hb_ot_apply_context_t *c, const OT::hb_ot_layout_lookup_accelerator_t &accel)
static const OT::GSUBGPOS & get_gsubgpos_table(hb_face_t *face, hb_tag_t table_tag)
static void apply_string(OT::hb_ot_apply_context_t *c, const typename Proxy::Lookup &lookup, const OT::hb_ot_layout_lookup_accelerator_t &accel)
static void script_collect_features(hb_collect_features_context_t *c, const OT::Script &s, const hb_tag_t *languages, const hb_tag_t *features)
static bool apply_forward(OT::hb_ot_apply_context_t *c, const OT::hb_ot_layout_lookup_accelerator_t &accel)
#define direction(p, c)
Definition: sh12.c:109
static mrb_value range_end(mrb_state *mrb, mrb_value range)
Definition: range.c:134
#define uintptr_t
Definition: stdint.in.h:321
GPOSProxy(hb_face_t *face)
OT::PosLookup Lookup
OT::SubstLookup Lookup
GSUBProxy(hb_face_t *face)
Definition: hb-null.hh:81
const FeatureParamsStylisticSet & get_stylistic_set_params(hb_tag_t tag) const
const FeatureParamsCharacterVariants & get_character_variants_params(hb_tag_t tag) const
static constexpr unsigned NOT_FOUND_INDEX
unsigned int get_glyph_props(hb_codepoint_t glyph) const
bool is_blocklisted(hb_blob_t *blob, hb_face_t *face) const
static void position_finish_offsets(hb_font_t *font, hb_buffer_t *buffer)
static void position_finish_advances(hb_font_t *font, hb_buffer_t *buffer)
static void position_start(hb_font_t *font, hb_buffer_t *buffer)
bool is_blocklisted(hb_blob_t *blob, hb_face_t *face) const
const Feature & get_feature(unsigned int i) const
unsigned int get_lookup_count() const
const Script & get_script(unsigned int i) const
unsigned int get_feature_count() const
hb_tag_t get_feature_tag(unsigned int i) const
bool is_blocklisted(hb_blob_t *blob, hb_face_t *face) const
const SubstLookup & get_lookup(unsigned int i) const
static constexpr unsigned NOT_FOUND_INDEX
hb_closure_context_t::return_t closure(hb_closure_context_t *c, unsigned int this_index) const
bool apply(hb_ot_apply_context_t *c) const
Definition: utils.c:300
Definition: libppm5.c:414
Definition: pbmfont.h:11
Definition: pbmfont.h:4
const Type * as() const
Definition: hb-blob.hh:59
unsigned int length
Definition: hb-blob.hh:65
bool visited(const T &p, hb_set_t &visited_set)
bool visited(const OT::LangSys &l)
hb_collect_features_context_t(hb_face_t *face, hb_tag_t table_tag, hb_set_t *feature_indexes_)
bool visited(const OT::Script &s)
bool visited_feature_indices(unsigned count)
auto _dispatch(const T &obj, hb_priority< 0 >, Ts &&... ds) -> decltype((default_return_value()))
auto _dispatch(const T &obj, hb_priority< 1 >, Ts &&... ds) -> decltype((obj.get_glyph_alternates(hb_forward< Ts >(ds)...)))
hb_get_glyph_alternates_dispatch_t(hb_face_t *face)
bool stop_sublookup_iteration(return_t r) const
void position(const struct hb_ot_shape_plan_t *plan, hb_font_t *font, hb_buffer_t *buffer) const
void apply(const Proxy &proxy, const struct hb_ot_shape_plan_t *plan, hb_font_t *font, hb_buffer_t *buffer) const
void substitute(const struct hb_ot_shape_plan_t *plan, hb_font_t *font, hb_buffer_t *buffer) const
void add(hb_codepoint_t g)
Definition: hb-set.hh:284
bool has(hb_codepoint_t k) const
Definition: hb-set.hh:448
Definition: mendex.h:20
Definition: afm2pl.c:145
Definition: zic.c:306
Definition: dvips.h:235
Definition: table.h:30
Definition: xmlparse.c:179
int j
Definition: t4ht.c:1589
#define return(val)