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-open-type.hh" 32 #include "hb-ot-layout.hh" 33 #include "hb-ot-face.hh" 34 #include "hb-ot-map.hh" 35 #include "hb-map.hh" 36 37 #include "hb-ot-kern-table.hh" 38 #include "hb-ot-gasp-table.hh" // Just so we compile it; unused otherwise. 39 #include "hb-ot-layout-gdef-table.hh" 40 #include "hb-ot-layout-gsub-table.hh" 41 #include "hb-ot-layout-gpos-table.hh" 42 #include "hb-ot-layout-base-table.hh" // Just so we compile it; unused otherwise. 43 #include "hb-ot-layout-jstf-table.hh" // Just so we compile it; unused otherwise. 44 #include "hb-ot-name-table.hh" 45 #include "hb-ot-os2-table.hh" 46 47 #include "hb-aat-layout-lcar-table.hh" 48 #include "hb-aat-layout-morx-table.hh" 49 50 51 /** 52 * SECTION:hb-ot-layout 53 * @title: hb-ot-layout 54 * @short_description: OpenType Layout 55 * @include: hb-ot.h 56 * 57 * Functions for querying OpenType Layout features in the font face. 58 **/ 59 60 61 /* 62 * kern 63 */ 64 65 bool 66 hb_ot_layout_has_kerning (hb_face_t *face) 67 { 68 return face->table.kern->has_data (); 69 } 70 71 bool 72 hb_ot_layout_has_machine_kerning (hb_face_t *face) 73 { 74 return face->table.kern->has_state_machine (); 75 } 76 77 bool 78 hb_ot_layout_has_cross_kerning (hb_face_t *face) 79 { 80 return face->table.kern->has_cross_stream (); 81 } 82 83 void 84 hb_ot_layout_kern (const hb_ot_shape_plan_t *plan, 85 hb_font_t *font, 86 hb_buffer_t *buffer) 87 { 88 hb_blob_t *blob = font->face->table.kern.get_blob (); 89 const AAT::kern& kern = *blob->as<AAT::kern> (); 90 91 AAT::hb_aat_apply_context_t c (plan, font, buffer, blob); 92 93 kern.apply (&c); 94 } 95 96 97 /* 98 * GDEF 99 */ 100 101 bool 102 OT::GDEF::is_blacklisted (hb_blob_t *blob, 103 hb_face_t *face) const 104 { 105 /* The ugly business of blacklisting individual fonts' tables happen here! 106 * See this thread for why we finally had to bend in and do this: 107 * https://lists.freedesktop.org/archives/harfbuzz/2016-February/005489.html 108 * 109 * In certain versions of Times New Roman Italic and Bold Italic, 110 * ASCII double quotation mark U+0022 has wrong glyph class 3 (mark) 111 * in GDEF. Many versions of Tahoma have bad GDEF tables that 112 * incorrectly classify some spacing marks such as certain IPA 113 * symbols as glyph class 3. So do older versions of Microsoft 114 * Himalaya, and the version of Cantarell shipped by Ubuntu 16.04. 115 * 116 * Nuke the GDEF tables of to avoid unwanted width-zeroing. 117 * 118 * See https://bugzilla.mozilla.org/show_bug.cgi?id=1279925 119 * https://bugzilla.mozilla.org/show_bug.cgi?id=1279693 120 * https://bugzilla.mozilla.org/show_bug.cgi?id=1279875 121 */ 122 #define ENCODE(x,y,z) (((uint64_t) (x) << 48) | ((uint64_t) (y) << 24) | (uint64_t) (z)) 123 switch ENCODE(blob->length, 124 face->table.GSUB->table.get_length (), 125 face->table.GPOS->table.get_length ()) 126 { 127 /* sha1sum:c5ee92f0bca4bfb7d06c4d03e8cf9f9cf75d2e8a Windows 7? timesi.ttf */ 128 case ENCODE (442, 2874, 42038): 129 /* sha1sum:37fc8c16a0894ab7b749e35579856c73c840867b Windows 7? timesbi.ttf */ 130 case ENCODE (430, 2874, 40662): 131 /* sha1sum:19fc45110ea6cd3cdd0a5faca256a3797a069a80 Windows 7 timesi.ttf */ 132 case ENCODE (442, 2874, 39116): 133 /* sha1sum:6d2d3c9ed5b7de87bc84eae0df95ee5232ecde26 Windows 7 timesbi.ttf */ 134 case ENCODE (430, 2874, 39374): 135 /* sha1sum:8583225a8b49667c077b3525333f84af08c6bcd8 OS X 10.11.3 Times New Roman Italic.ttf */ 136 case ENCODE (490, 3046, 41638): 137 /* sha1sum:ec0f5a8751845355b7c3271d11f9918a966cb8c9 OS X 10.11.3 Times New Roman Bold Italic.ttf */ 138 case ENCODE (478, 3046, 41902): 139 /* sha1sum:96eda93f7d33e79962451c6c39a6b51ee893ce8c tahoma.ttf from Windows 8 */ 140 case ENCODE (898, 12554, 46470): 141 /* sha1sum:20928dc06014e0cd120b6fc942d0c3b1a46ac2bc tahomabd.ttf from Windows 8 */ 142 case ENCODE (910, 12566, 47732): 143 /* sha1sum:4f95b7e4878f60fa3a39ca269618dfde9721a79e tahoma.ttf from Windows 8.1 */ 144 case ENCODE (928, 23298, 59332): 145 /* sha1sum:6d400781948517c3c0441ba42acb309584b73033 tahomabd.ttf from Windows 8.1 */ 146 case ENCODE (940, 23310, 60732): 147 /* tahoma.ttf v6.04 from Windows 8.1 x64, see https://bugzilla.mozilla.org/show_bug.cgi?id=1279925 */ 148 case ENCODE (964, 23836, 60072): 149 /* tahomabd.ttf v6.04 from Windows 8.1 x64, see https://bugzilla.mozilla.org/show_bug.cgi?id=1279925 */ 150 case ENCODE (976, 23832, 61456): 151 /* sha1sum:e55fa2dfe957a9f7ec26be516a0e30b0c925f846 tahoma.ttf from Windows 10 */ 152 case ENCODE (994, 24474, 60336): 153 /* sha1sum:7199385abb4c2cc81c83a151a7599b6368e92343 tahomabd.ttf from Windows 10 */ 154 case ENCODE (1006, 24470, 61740): 155 /* tahoma.ttf v6.91 from Windows 10 x64, see https://bugzilla.mozilla.org/show_bug.cgi?id=1279925 */ 156 case ENCODE (1006, 24576, 61346): 157 /* tahomabd.ttf v6.91 from Windows 10 x64, see https://bugzilla.mozilla.org/show_bug.cgi?id=1279925 */ 158 case ENCODE (1018, 24572, 62828): 159 /* sha1sum:b9c84d820c49850d3d27ec498be93955b82772b5 tahoma.ttf from Windows 10 AU */ 160 case ENCODE (1006, 24576, 61352): 161 /* sha1sum:2bdfaab28174bdadd2f3d4200a30a7ae31db79d2 tahomabd.ttf from Windows 10 AU */ 162 case ENCODE (1018, 24572, 62834): 163 /* sha1sum:b0d36cf5a2fbe746a3dd277bffc6756a820807a7 Tahoma.ttf from Mac OS X 10.9 */ 164 case ENCODE (832, 7324, 47162): 165 /* sha1sum:12fc4538e84d461771b30c18b5eb6bd434e30fba Tahoma Bold.ttf from Mac OS X 10.9 */ 166 case ENCODE (844, 7302, 45474): 167 /* sha1sum:eb8afadd28e9cf963e886b23a30b44ab4fd83acc himalaya.ttf from Windows 7 */ 168 case ENCODE (180, 13054, 7254): 169 /* sha1sum:73da7f025b238a3f737aa1fde22577a6370f77b0 himalaya.ttf from Windows 8 */ 170 case ENCODE (192, 12638, 7254): 171 /* sha1sum:6e80fd1c0b059bbee49272401583160dc1e6a427 himalaya.ttf from Windows 8.1 */ 172 case ENCODE (192, 12690, 7254): 173 /* 8d9267aea9cd2c852ecfb9f12a6e834bfaeafe44 cantarell-fonts-0.0.21/otf/Cantarell-Regular.otf */ 174 /* 983988ff7b47439ab79aeaf9a45bd4a2c5b9d371 cantarell-fonts-0.0.21/otf/Cantarell-Oblique.otf */ 175 case ENCODE (188, 248, 3852): 176 /* 2c0c90c6f6087ffbfea76589c93113a9cbb0e75f cantarell-fonts-0.0.21/otf/Cantarell-Bold.otf */ 177 /* 55461f5b853c6da88069ffcdf7f4dd3f8d7e3e6b cantarell-fonts-0.0.21/otf/Cantarell-Bold-Oblique.otf */ 178 case ENCODE (188, 264, 3426): 179 /* d125afa82a77a6475ac0e74e7c207914af84b37a padauk-2.80/Padauk.ttf RHEL 7.2 */ 180 case ENCODE (1058, 47032, 11818): 181 /* 0f7b80437227b90a577cc078c0216160ae61b031 padauk-2.80/Padauk-Bold.ttf RHEL 7.2*/ 182 case ENCODE (1046, 47030, 12600): 183 /* d3dde9aa0a6b7f8f6a89ef1002e9aaa11b882290 padauk-2.80/Padauk.ttf Ubuntu 16.04 */ 184 case ENCODE (1058, 71796, 16770): 185 /* 5f3c98ccccae8a953be2d122c1b3a77fd805093f padauk-2.80/Padauk-Bold.ttf Ubuntu 16.04 */ 186 case ENCODE (1046, 71790, 17862): 187 /* 6c93b63b64e8b2c93f5e824e78caca555dc887c7 padauk-2.80/Padauk-book.ttf */ 188 case ENCODE (1046, 71788, 17112): 189 /* d89b1664058359b8ec82e35d3531931125991fb9 padauk-2.80/Padauk-bookbold.ttf */ 190 case ENCODE (1058, 71794, 17514): 191 /* 824cfd193aaf6234b2b4dc0cf3c6ef576c0d00ef padauk-3.0/Padauk-book.ttf */ 192 case ENCODE (1330, 109904, 57938): 193 /* 91fcc10cf15e012d27571e075b3b4dfe31754a8a padauk-3.0/Padauk-bookbold.ttf */ 194 case ENCODE (1330, 109904, 58972): 195 /* sha1sum: c26e41d567ed821bed997e937bc0c41435689e85 Padauk.ttf 196 * "Padauk Regular" "Version 2.5", see https://crbug.com/681813 */ 197 case ENCODE (1004, 59092, 14836): 198 return true; 199 #undef ENCODE 200 } 201 return false; 202 } 203 204 static void 205 _hb_ot_layout_set_glyph_props (hb_font_t *font, 206 hb_buffer_t *buffer) 207 { 208 _hb_buffer_assert_gsubgpos_vars (buffer); 209 210 const OT::GDEF &gdef = *font->face->table.GDEF->table; 211 unsigned int count = buffer->len; 212 for (unsigned int i = 0; i < count; i++) 213 { 214 _hb_glyph_info_set_glyph_props (&buffer->info[i], gdef.get_glyph_props (buffer->info[i].codepoint)); 215 _hb_glyph_info_clear_lig_props (&buffer->info[i]); 216 buffer->info[i].syllable() = 0; 217 } 218 } 219 220 /* Public API */ 221 222 hb_bool_t 223 hb_ot_layout_has_glyph_classes (hb_face_t *face) 224 { 225 return face->table.GDEF->table->has_glyph_classes (); 226 } 227 228 /** 229 * hb_ot_layout_get_glyph_class: 230 * 231 * Since: 0.9.7 232 **/ 233 hb_ot_layout_glyph_class_t 234 hb_ot_layout_get_glyph_class (hb_face_t *face, 235 hb_codepoint_t glyph) 236 { 237 return (hb_ot_layout_glyph_class_t) face->table.GDEF->table->get_glyph_class (glyph); 238 } 239 240 /** 241 * hb_ot_layout_get_glyphs_in_class: 242 * 243 * Since: 0.9.7 244 **/ 245 void 246 hb_ot_layout_get_glyphs_in_class (hb_face_t *face, 247 hb_ot_layout_glyph_class_t klass, 248 hb_set_t *glyphs /* OUT */) 249 { 250 return face->table.GDEF->table->get_glyphs_in_class (klass, glyphs); 251 } 252 253 unsigned int 254 hb_ot_layout_get_attach_points (hb_face_t *face, 255 hb_codepoint_t glyph, 256 unsigned int start_offset, 257 unsigned int *point_count /* IN/OUT */, 258 unsigned int *point_array /* OUT */) 259 { 260 return face->table.GDEF->table->get_attach_points (glyph, 261 start_offset, 262 point_count, 263 point_array); 264 } 265 266 unsigned int 267 hb_ot_layout_get_ligature_carets (hb_font_t *font, 268 hb_direction_t direction, 269 hb_codepoint_t glyph, 270 unsigned int start_offset, 271 unsigned int *caret_count /* IN/OUT */, 272 hb_position_t *caret_array /* OUT */) 273 { 274 unsigned int result_caret_count = 0; 275 unsigned int result = font->face->table.GDEF->table->get_lig_carets (font, direction, glyph, start_offset, &result_caret_count, caret_array); 276 if (result) 277 { 278 if (caret_count) *caret_count = result_caret_count; 279 } 280 else 281 result = font->face->table.lcar->get_lig_carets (font, direction, glyph, start_offset, caret_count, caret_array); 282 return result; 283 } 284 285 286 /* 287 * GSUB/GPOS 288 */ 289 290 bool 291 OT::GSUB::is_blacklisted (hb_blob_t *blob HB_UNUSED, 292 hb_face_t *face) const 293 { 294 /* Mac OS X prefers morx over GSUB. It also ships with various Indic fonts, 295 * all by 'MUTF' foundry (Tamil MN, Tamil Sangam MN, etc.), that have broken 296 * GSUB/GPOS tables. Some have GSUB with zero scripts, those are ignored by 297 * our morx/GSUB preference code. But if GSUB has non-zero scripts, we tend 298 * to prefer it over morx because we want to be consistent with other OpenType 299 * shapers. 300 * 301 * To work around broken Indic Mac system fonts, we ignore GSUB table if 302 * OS/2 VendorId is 'MUTF' and font has morx table as well. 303 * 304 * https://github.com/harfbuzz/harfbuzz/issues/1410 305 * https://github.com/harfbuzz/harfbuzz/issues/1348 306 * https://github.com/harfbuzz/harfbuzz/issues/1391 307 */ 308 if (unlikely (face->table.OS2->achVendID == HB_TAG ('M','U','T','F') && 309 face->table.morx->has_data ())) 310 return true; 311 312 return false; 313 } 314 315 bool 316 OT::GPOS::is_blacklisted (hb_blob_t *blob HB_UNUSED, 317 hb_face_t *face HB_UNUSED) const 318 { 319 return false; 320 } 321 322 static const OT::GSUBGPOS& 323 get_gsubgpos_table (hb_face_t *face, 324 hb_tag_t table_tag) 325 { 326 switch (table_tag) { 327 case HB_OT_TAG_GSUB: return *face->table.GSUB->table; 328 case HB_OT_TAG_GPOS: return *face->table.GPOS->table; 329 default: return Null(OT::GSUBGPOS); 330 } 331 } 332 333 334 unsigned int 335 hb_ot_layout_table_get_script_tags (hb_face_t *face, 336 hb_tag_t table_tag, 337 unsigned int start_offset, 338 unsigned int *script_count /* IN/OUT */, 339 hb_tag_t *script_tags /* OUT */) 340 { 341 const OT::GSUBGPOS &g = get_gsubgpos_table (face, table_tag); 342 343 return g.get_script_tags (start_offset, script_count, script_tags); 344 } 345 346 #define HB_OT_TAG_LATIN_SCRIPT HB_TAG ('l', 'a', 't', 'n') 347 348 hb_bool_t 349 hb_ot_layout_table_find_script (hb_face_t *face, 350 hb_tag_t table_tag, 351 hb_tag_t script_tag, 352 unsigned int *script_index) 353 { 354 static_assert ((OT::Index::NOT_FOUND_INDEX == HB_OT_LAYOUT_NO_SCRIPT_INDEX), ""); 355 const OT::GSUBGPOS &g = get_gsubgpos_table (face, table_tag); 356 357 if (g.find_script_index (script_tag, script_index)) 358 return true; 359 360 /* try finding 'DFLT' */ 361 if (g.find_script_index (HB_OT_TAG_DEFAULT_SCRIPT, script_index)) 362 return false; 363 364 /* try with 'dflt'; MS site has had typos and many fonts use it now :(. 365 * including many versions of DejaVu Sans Mono! */ 366 if (g.find_script_index (HB_OT_TAG_DEFAULT_LANGUAGE, script_index)) 367 return false; 368 369 /* try with 'latn'; some old fonts put their features there even though 370 they're really trying to support Thai, for example :( */ 371 if (g.find_script_index (HB_OT_TAG_LATIN_SCRIPT, script_index)) 372 return false; 373 374 if (script_index) *script_index = HB_OT_LAYOUT_NO_SCRIPT_INDEX; 375 return false; 376 } 377 378 hb_bool_t 379 hb_ot_layout_table_choose_script (hb_face_t *face, 380 hb_tag_t table_tag, 381 const hb_tag_t *script_tags, 382 unsigned int *script_index, 383 hb_tag_t *chosen_script) 384 { 385 const hb_tag_t *t; 386 for (t = script_tags; *t; t++); 387 return hb_ot_layout_table_select_script (face, table_tag, t - script_tags, script_tags, script_index, chosen_script); 388 } 389 390 /** 391 * hb_ot_layout_table_select_script: 392 * 393 * Since: 2.0.0 394 **/ 395 hb_bool_t 396 hb_ot_layout_table_select_script (hb_face_t *face, 397 hb_tag_t table_tag, 398 unsigned int script_count, 399 const hb_tag_t *script_tags, 400 unsigned int *script_index /* OUT */, 401 hb_tag_t *chosen_script /* OUT */) 402 { 403 static_assert ((OT::Index::NOT_FOUND_INDEX == HB_OT_LAYOUT_NO_SCRIPT_INDEX), ""); 404 const OT::GSUBGPOS &g = get_gsubgpos_table (face, table_tag); 405 unsigned int i; 406 407 for (i = 0; i < script_count; i++) 408 { 409 if (g.find_script_index (script_tags[i], script_index)) 410 { 411 if (chosen_script) 412 *chosen_script = script_tags[i]; 413 return true; 414 } 415 } 416 417 /* try finding 'DFLT' */ 418 if (g.find_script_index (HB_OT_TAG_DEFAULT_SCRIPT, script_index)) { 419 if (chosen_script) 420 *chosen_script = HB_OT_TAG_DEFAULT_SCRIPT; 421 return false; 422 } 423 424 /* try with 'dflt'; MS site has had typos and many fonts use it now :( */ 425 if (g.find_script_index (HB_OT_TAG_DEFAULT_LANGUAGE, script_index)) { 426 if (chosen_script) 427 *chosen_script = HB_OT_TAG_DEFAULT_LANGUAGE; 428 return false; 429 } 430 431 /* try with 'latn'; some old fonts put their features there even though 432 they're really trying to support Thai, for example :( */ 433 if (g.find_script_index (HB_OT_TAG_LATIN_SCRIPT, script_index)) { 434 if (chosen_script) 435 *chosen_script = HB_OT_TAG_LATIN_SCRIPT; 436 return false; 437 } 438 439 if (script_index) *script_index = HB_OT_LAYOUT_NO_SCRIPT_INDEX; 440 if (chosen_script) 441 *chosen_script = HB_OT_LAYOUT_NO_SCRIPT_INDEX; 442 return false; 443 } 444 445 unsigned int 446 hb_ot_layout_table_get_feature_tags (hb_face_t *face, 447 hb_tag_t table_tag, 448 unsigned int start_offset, 449 unsigned int *feature_count /* IN/OUT */, 450 hb_tag_t *feature_tags /* OUT */) 451 { 452 const OT::GSUBGPOS &g = get_gsubgpos_table (face, table_tag); 453 454 return g.get_feature_tags (start_offset, feature_count, feature_tags); 455 } 456 457 bool 458 hb_ot_layout_table_find_feature (hb_face_t *face, 459 hb_tag_t table_tag, 460 hb_tag_t feature_tag, 461 unsigned int *feature_index) 462 { 463 static_assert ((OT::Index::NOT_FOUND_INDEX == HB_OT_LAYOUT_NO_FEATURE_INDEX), ""); 464 const OT::GSUBGPOS &g = get_gsubgpos_table (face, table_tag); 465 466 unsigned int num_features = g.get_feature_count (); 467 for (unsigned int i = 0; i < num_features; i++) 468 { 469 if (feature_tag == g.get_feature_tag (i)) { 470 if (feature_index) *feature_index = i; 471 return true; 472 } 473 } 474 475 if (feature_index) *feature_index = HB_OT_LAYOUT_NO_FEATURE_INDEX; 476 return false; 477 } 478 479 480 unsigned int 481 hb_ot_layout_script_get_language_tags (hb_face_t *face, 482 hb_tag_t table_tag, 483 unsigned int script_index, 484 unsigned int start_offset, 485 unsigned int *language_count /* IN/OUT */, 486 hb_tag_t *language_tags /* OUT */) 487 { 488 const OT::Script &s = get_gsubgpos_table (face, table_tag).get_script (script_index); 489 490 return s.get_lang_sys_tags (start_offset, language_count, language_tags); 491 } 492 493 hb_bool_t 494 hb_ot_layout_script_find_language (hb_face_t *face, 495 hb_tag_t table_tag, 496 unsigned int script_index, 497 hb_tag_t language_tag, 498 unsigned int *language_index) 499 { 500 return hb_ot_layout_script_select_language (face, 501 table_tag, 502 script_index, 503 1, 504 &language_tag, 505 language_index); 506 } 507 508 /** 509 * hb_ot_layout_script_select_language: 510 * 511 * Since: 2.0.0 512 **/ 513 hb_bool_t 514 hb_ot_layout_script_select_language (hb_face_t *face, 515 hb_tag_t table_tag, 516 unsigned int script_index, 517 unsigned int language_count, 518 const hb_tag_t *language_tags, 519 unsigned int *language_index /* OUT */) 520 { 521 static_assert ((OT::Index::NOT_FOUND_INDEX == HB_OT_LAYOUT_DEFAULT_LANGUAGE_INDEX), ""); 522 const OT::Script &s = get_gsubgpos_table (face, table_tag).get_script (script_index); 523 unsigned int i; 524 525 for (i = 0; i < language_count; i++) 526 { 527 if (s.find_lang_sys_index (language_tags[i], language_index)) 528 return true; 529 } 530 531 /* try finding 'dflt' */ 532 if (s.find_lang_sys_index (HB_OT_TAG_DEFAULT_LANGUAGE, language_index)) 533 return false; 534 535 if (language_index) *language_index = HB_OT_LAYOUT_DEFAULT_LANGUAGE_INDEX; 536 return false; 537 } 538 539 hb_bool_t 540 hb_ot_layout_language_get_required_feature_index (hb_face_t *face, 541 hb_tag_t table_tag, 542 unsigned int script_index, 543 unsigned int language_index, 544 unsigned int *feature_index) 545 { 546 return hb_ot_layout_language_get_required_feature (face, 547 table_tag, 548 script_index, 549 language_index, 550 feature_index, 551 nullptr); 552 } 553 554 /** 555 * hb_ot_layout_language_get_required_feature: 556 * 557 * Since: 0.9.30 558 **/ 559 hb_bool_t 560 hb_ot_layout_language_get_required_feature (hb_face_t *face, 561 hb_tag_t table_tag, 562 unsigned int script_index, 563 unsigned int language_index, 564 unsigned int *feature_index, 565 hb_tag_t *feature_tag) 566 { 567 const OT::GSUBGPOS &g = get_gsubgpos_table (face, table_tag); 568 const OT::LangSys &l = g.get_script (script_index).get_lang_sys (language_index); 569 570 unsigned int index = l.get_required_feature_index (); 571 if (feature_index) *feature_index = index; 572 if (feature_tag) *feature_tag = g.get_feature_tag (index); 573 574 return l.has_required_feature (); 575 } 576 577 unsigned int 578 hb_ot_layout_language_get_feature_indexes (hb_face_t *face, 579 hb_tag_t table_tag, 580 unsigned int script_index, 581 unsigned int language_index, 582 unsigned int start_offset, 583 unsigned int *feature_count /* IN/OUT */, 584 unsigned int *feature_indexes /* OUT */) 585 { 586 const OT::GSUBGPOS &g = get_gsubgpos_table (face, table_tag); 587 const OT::LangSys &l = g.get_script (script_index).get_lang_sys (language_index); 588 589 return l.get_feature_indexes (start_offset, feature_count, feature_indexes); 590 } 591 592 unsigned int 593 hb_ot_layout_language_get_feature_tags (hb_face_t *face, 594 hb_tag_t table_tag, 595 unsigned int script_index, 596 unsigned int language_index, 597 unsigned int start_offset, 598 unsigned int *feature_count /* IN/OUT */, 599 hb_tag_t *feature_tags /* OUT */) 600 { 601 const OT::GSUBGPOS &g = get_gsubgpos_table (face, table_tag); 602 const OT::LangSys &l = g.get_script (script_index).get_lang_sys (language_index); 603 604 static_assert ((sizeof (unsigned int) == sizeof (hb_tag_t)), ""); 605 unsigned int ret = l.get_feature_indexes (start_offset, feature_count, (unsigned int *) feature_tags); 606 607 if (feature_tags) { 608 unsigned int count = *feature_count; 609 for (unsigned int i = 0; i < count; i++) 610 feature_tags[i] = g.get_feature_tag ((unsigned int) feature_tags[i]); 611 } 612 613 return ret; 614 } 615 616 617 hb_bool_t 618 hb_ot_layout_language_find_feature (hb_face_t *face, 619 hb_tag_t table_tag, 620 unsigned int script_index, 621 unsigned int language_index, 622 hb_tag_t feature_tag, 623 unsigned int *feature_index) 624 { 625 static_assert ((OT::Index::NOT_FOUND_INDEX == HB_OT_LAYOUT_NO_FEATURE_INDEX), ""); 626 const OT::GSUBGPOS &g = get_gsubgpos_table (face, table_tag); 627 const OT::LangSys &l = g.get_script (script_index).get_lang_sys (language_index); 628 629 unsigned int num_features = l.get_feature_count (); 630 for (unsigned int i = 0; i < num_features; i++) { 631 unsigned int f_index = l.get_feature_index (i); 632 633 if (feature_tag == g.get_feature_tag (f_index)) { 634 if (feature_index) *feature_index = f_index; 635 return true; 636 } 637 } 638 639 if (feature_index) *feature_index = HB_OT_LAYOUT_NO_FEATURE_INDEX; 640 return false; 641 } 642 643 /** 644 * hb_ot_layout_feature_get_lookups: 645 * 646 * Since: 0.9.7 647 **/ 648 unsigned int 649 hb_ot_layout_feature_get_lookups (hb_face_t *face, 650 hb_tag_t table_tag, 651 unsigned int feature_index, 652 unsigned int start_offset, 653 unsigned int *lookup_count /* IN/OUT */, 654 unsigned int *lookup_indexes /* OUT */) 655 { 656 return hb_ot_layout_feature_with_variations_get_lookups (face, 657 table_tag, 658 feature_index, 659 HB_OT_LAYOUT_NO_VARIATIONS_INDEX, 660 start_offset, 661 lookup_count, 662 lookup_indexes); 663 } 664 665 /** 666 * hb_ot_layout_table_get_lookup_count: 667 * 668 * Since: 0.9.22 669 **/ 670 unsigned int 671 hb_ot_layout_table_get_lookup_count (hb_face_t *face, 672 hb_tag_t table_tag) 673 { 674 return get_gsubgpos_table (face, table_tag).get_lookup_count (); 675 } 676 677 678 struct hb_collect_features_context_t 679 { 680 hb_collect_features_context_t (hb_face_t *face, 681 hb_tag_t table_tag, 682 hb_set_t *feature_indexes_) 683 : g (get_gsubgpos_table (face, table_tag)), 684 feature_indexes (feature_indexes_), 685 script_count(0),langsys_count(0) {} 686 687 bool inline visited (const OT::Script &s) 688 { 689 /* We might have Null() object here. Don't want to involve 690 * that in the memoize. So, detect empty objects and return. */ 691 if (unlikely (!s.has_default_lang_sys () && 692 !s.get_lang_sys_count ())) 693 return true; 694 695 if (script_count++ > HB_MAX_SCRIPTS) 696 return true; 697 698 return visited (s, visited_script); 699 } 700 bool inline visited (const OT::LangSys &l) 701 { 702 /* We might have Null() object here. Don't want to involve 703 * that in the memoize. So, detect empty objects and return. */ 704 if (unlikely (!l.has_required_feature () && 705 !l.get_feature_count ())) 706 return true; 707 708 if (langsys_count++ > HB_MAX_LANGSYS) 709 return true; 710 711 return visited (l, visited_langsys); 712 } 713 714 private: 715 template <typename T> 716 bool inline visited (const T &p, hb_set_t &visited_set) 717 { 718 hb_codepoint_t delta = (hb_codepoint_t) ((uintptr_t) &p - (uintptr_t) &g); 719 if (visited_set.has (delta)) 720 return true; 721 722 visited_set.add (delta); 723 return false; 724 } 725 726 public: 727 const OT::GSUBGPOS &g; 728 hb_set_t *feature_indexes; 729 730 private: 731 hb_set_t visited_script; 732 hb_set_t visited_langsys; 733 unsigned int script_count; 734 unsigned int langsys_count; 735 }; 736 737 static void 738 langsys_collect_features (hb_collect_features_context_t *c, 739 const OT::LangSys &l, 740 const hb_tag_t *features) 741 { 742 if (c->visited (l)) return; 743 744 if (!features) 745 { 746 /* All features. */ 747 if (l.has_required_feature ()) 748 c->feature_indexes->add (l.get_required_feature_index ()); 749 750 l.add_feature_indexes_to (c->feature_indexes); 751 } 752 else 753 { 754 /* Ugh. Any faster way? */ 755 for (; *features; features++) 756 { 757 hb_tag_t feature_tag = *features; 758 unsigned int num_features = l.get_feature_count (); 759 for (unsigned int i = 0; i < num_features; i++) 760 { 761 unsigned int feature_index = l.get_feature_index (i); 762 763 if (feature_tag == c->g.get_feature_tag (feature_index)) 764 { 765 c->feature_indexes->add (feature_index); 766 break; 767 } 768 } 769 } 770 } 771 } 772 773 static void 774 script_collect_features (hb_collect_features_context_t *c, 775 const OT::Script &s, 776 const hb_tag_t *languages, 777 const hb_tag_t *features) 778 { 779 if (c->visited (s)) return; 780 781 if (!languages) 782 { 783 /* All languages. */ 784 if (s.has_default_lang_sys ()) 785 langsys_collect_features (c, 786 s.get_default_lang_sys (), 787 features); 788 789 unsigned int count = s.get_lang_sys_count (); 790 for (unsigned int language_index = 0; language_index < count; language_index++) 791 langsys_collect_features (c, 792 s.get_lang_sys (language_index), 793 features); 794 } 795 else 796 { 797 for (; *languages; languages++) 798 { 799 unsigned int language_index; 800 if (s.find_lang_sys_index (*languages, &language_index)) 801 langsys_collect_features (c, 802 s.get_lang_sys (language_index), 803 features); 804 } 805 } 806 } 807 808 /** 809 * hb_ot_layout_collect_features: 810 * 811 * Since: 1.8.5 812 **/ 813 void 814 hb_ot_layout_collect_features (hb_face_t *face, 815 hb_tag_t table_tag, 816 const hb_tag_t *scripts, 817 const hb_tag_t *languages, 818 const hb_tag_t *features, 819 hb_set_t *feature_indexes /* OUT */) 820 { 821 hb_collect_features_context_t c (face, table_tag, feature_indexes); 822 if (!scripts) 823 { 824 /* All scripts. */ 825 unsigned int count = c.g.get_script_count (); 826 for (unsigned int script_index = 0; script_index < count; script_index++) 827 script_collect_features (&c, 828 c.g.get_script (script_index), 829 languages, 830 features); 831 } 832 else 833 { 834 for (; *scripts; scripts++) 835 { 836 unsigned int script_index; 837 if (c.g.find_script_index (*scripts, &script_index)) 838 script_collect_features (&c, 839 c.g.get_script (script_index), 840 languages, 841 features); 842 } 843 } 844 } 845 846 /** 847 * hb_ot_layout_collect_lookups: 848 * 849 * Since: 0.9.8 850 **/ 851 void 852 hb_ot_layout_collect_lookups (hb_face_t *face, 853 hb_tag_t table_tag, 854 const hb_tag_t *scripts, 855 const hb_tag_t *languages, 856 const hb_tag_t *features, 857 hb_set_t *lookup_indexes /* OUT */) 858 { 859 const OT::GSUBGPOS &g = get_gsubgpos_table (face, table_tag); 860 861 hb_set_t feature_indexes; 862 hb_ot_layout_collect_features (face, table_tag, scripts, languages, features, &feature_indexes); 863 864 for (hb_codepoint_t feature_index = HB_SET_VALUE_INVALID; 865 hb_set_next (&feature_indexes, &feature_index);) 866 g.get_feature (feature_index).add_lookup_indexes_to (lookup_indexes); 867 } 868 869 /** 870 * hb_ot_layout_lookup_collect_glyphs: 871 * 872 * Since: 0.9.7 873 **/ 874 void 875 hb_ot_layout_lookup_collect_glyphs (hb_face_t *face, 876 hb_tag_t table_tag, 877 unsigned int lookup_index, 878 hb_set_t *glyphs_before, /* OUT. May be NULL */ 879 hb_set_t *glyphs_input, /* OUT. May be NULL */ 880 hb_set_t *glyphs_after, /* OUT. May be NULL */ 881 hb_set_t *glyphs_output /* OUT. May be NULL */) 882 { 883 OT::hb_collect_glyphs_context_t c (face, 884 glyphs_before, 885 glyphs_input, 886 glyphs_after, 887 glyphs_output); 888 889 switch (table_tag) 890 { 891 case HB_OT_TAG_GSUB: 892 { 893 const OT::SubstLookup& l = face->table.GSUB->table->get_lookup (lookup_index); 894 l.collect_glyphs (&c); 895 return; 896 } 897 case HB_OT_TAG_GPOS: 898 { 899 const OT::PosLookup& l = face->table.GPOS->table->get_lookup (lookup_index); 900 l.collect_glyphs (&c); 901 return; 902 } 903 } 904 } 905 906 907 /* Variations support */ 908 909 hb_bool_t 910 hb_ot_layout_table_find_feature_variations (hb_face_t *face, 911 hb_tag_t table_tag, 912 const int *coords, 913 unsigned int num_coords, 914 unsigned int *variations_index /* out */) 915 { 916 const OT::GSUBGPOS &g = get_gsubgpos_table (face, table_tag); 917 918 return g.find_variations_index (coords, num_coords, variations_index); 919 } 920 921 unsigned int 922 hb_ot_layout_feature_with_variations_get_lookups (hb_face_t *face, 923 hb_tag_t table_tag, 924 unsigned int feature_index, 925 unsigned int variations_index, 926 unsigned int start_offset, 927 unsigned int *lookup_count /* IN/OUT */, 928 unsigned int *lookup_indexes /* OUT */) 929 { 930 static_assert ((OT::FeatureVariations::NOT_FOUND_INDEX == HB_OT_LAYOUT_NO_VARIATIONS_INDEX), ""); 931 const OT::GSUBGPOS &g = get_gsubgpos_table (face, table_tag); 932 933 const OT::Feature &f = g.get_feature_variation (feature_index, variations_index); 934 935 return f.get_lookup_indexes (start_offset, lookup_count, lookup_indexes); 936 } 937 938 939 /* 940 * OT::GSUB 941 */ 942 943 hb_bool_t 944 hb_ot_layout_has_substitution (hb_face_t *face) 945 { 946 return face->table.GSUB->table->has_data (); 947 } 948 949 /** 950 * hb_ot_layout_lookup_would_substitute: 951 * 952 * Since: 0.9.7 953 **/ 954 hb_bool_t 955 hb_ot_layout_lookup_would_substitute (hb_face_t *face, 956 unsigned int lookup_index, 957 const hb_codepoint_t *glyphs, 958 unsigned int glyphs_length, 959 hb_bool_t zero_context) 960 { 961 return hb_ot_layout_lookup_would_substitute_fast (face, 962 lookup_index, 963 glyphs, glyphs_length, 964 zero_context); 965 } 966 967 bool 968 hb_ot_layout_lookup_would_substitute_fast (hb_face_t *face, 969 unsigned int lookup_index, 970 const hb_codepoint_t *glyphs, 971 unsigned int glyphs_length, 972 bool zero_context) 973 { 974 if (unlikely (lookup_index >= face->table.GSUB->lookup_count)) return false; 975 OT::hb_would_apply_context_t c (face, glyphs, glyphs_length, (bool) zero_context); 976 977 const OT::SubstLookup& l = face->table.GSUB->table->get_lookup (lookup_index); 978 979 return l.would_apply (&c, &face->table.GSUB->accels[lookup_index]); 980 } 981 982 void 983 hb_ot_layout_substitute_start (hb_font_t *font, 984 hb_buffer_t *buffer) 985 { 986 _hb_ot_layout_set_glyph_props (font, buffer); 987 } 988 989 void 990 hb_ot_layout_delete_glyphs_inplace (hb_buffer_t *buffer, 991 bool (*filter) (const hb_glyph_info_t *info)) 992 { 993 /* Merge clusters and delete filtered glyphs. 994 * NOTE! We can't use out-buffer as we have positioning data. */ 995 unsigned int j = 0; 996 unsigned int count = buffer->len; 997 hb_glyph_info_t *info = buffer->info; 998 hb_glyph_position_t *pos = buffer->pos; 999 for (unsigned int i = 0; i < count; i++) 1000 { 1001 if (filter (&info[i])) 1002 { 1003 /* Merge clusters. 1004 * Same logic as buffer->delete_glyph(), but for in-place removal. */ 1005 1006 unsigned int cluster = info[i].cluster; 1007 if (i + 1 < count && cluster == info[i + 1].cluster) 1008 continue; /* Cluster survives; do nothing. */ 1009 1010 if (j) 1011 { 1012 /* Merge cluster backward. */ 1013 if (cluster < info[j - 1].cluster) 1014 { 1015 unsigned int mask = info[i].mask; 1016 unsigned int old_cluster = info[j - 1].cluster; 1017 for (unsigned k = j; k && info[k - 1].cluster == old_cluster; k--) 1018 buffer->set_cluster (info[k - 1], cluster, mask); 1019 } 1020 continue; 1021 } 1022 1023 if (i + 1 < count) 1024 buffer->merge_clusters (i, i + 2); /* Merge cluster forward. */ 1025 1026 continue; 1027 } 1028 1029 if (j != i) 1030 { 1031 info[j] = info[i]; 1032 pos[j] = pos[i]; 1033 } 1034 j++; 1035 } 1036 buffer->len = j; 1037 } 1038 1039 /** 1040 * hb_ot_layout_lookup_substitute_closure: 1041 * 1042 * Since: 0.9.7 1043 **/ 1044 void 1045 hb_ot_layout_lookup_substitute_closure (hb_face_t *face, 1046 unsigned int lookup_index, 1047 hb_set_t *glyphs) 1048 { 1049 hb_map_t done_lookups; 1050 OT::hb_closure_context_t c (face, glyphs, &done_lookups); 1051 1052 const OT::SubstLookup& l = face->table.GSUB->table->get_lookup (lookup_index); 1053 1054 l.closure (&c, lookup_index); 1055 } 1056 1057 /** 1058 * hb_ot_layout_lookups_substitute_closure: 1059 * 1060 * Compute the transitive closure of glyphs needed for all of the 1061 * provided lookups. 1062 * 1063 * Since: 1.8.1 1064 **/ 1065 void 1066 hb_ot_layout_lookups_substitute_closure (hb_face_t *face, 1067 const hb_set_t *lookups, 1068 hb_set_t *glyphs) 1069 { 1070 hb_map_t done_lookups; 1071 OT::hb_closure_context_t c (face, glyphs, &done_lookups); 1072 const OT::GSUB& gsub = *face->table.GSUB->table; 1073 1074 unsigned int iteration_count = 0; 1075 unsigned int glyphs_length; 1076 do 1077 { 1078 glyphs_length = glyphs->get_population (); 1079 if (lookups != nullptr) 1080 { 1081 for (hb_codepoint_t lookup_index = HB_SET_VALUE_INVALID; hb_set_next (lookups, &lookup_index);) 1082 gsub.get_lookup (lookup_index).closure (&c, lookup_index); 1083 } 1084 else 1085 { 1086 for (unsigned int i = 0; i < gsub.get_lookup_count (); i++) 1087 gsub.get_lookup (i).closure (&c, i); 1088 } 1089 } while (iteration_count++ <= HB_CLOSURE_MAX_STAGES && 1090 glyphs_length != glyphs->get_population ()); 1091 } 1092 1093 /* 1094 * OT::GPOS 1095 */ 1096 1097 hb_bool_t 1098 hb_ot_layout_has_positioning (hb_face_t *face) 1099 { 1100 return face->table.GPOS->table->has_data (); 1101 } 1102 1103 void 1104 hb_ot_layout_position_start (hb_font_t *font, hb_buffer_t *buffer) 1105 { 1106 OT::GPOS::position_start (font, buffer); 1107 } 1108 1109 void 1110 hb_ot_layout_position_finish_advances (hb_font_t *font, hb_buffer_t *buffer) 1111 { 1112 OT::GPOS::position_finish_advances (font, buffer); 1113 } 1114 1115 void 1116 hb_ot_layout_position_finish_offsets (hb_font_t *font, hb_buffer_t *buffer) 1117 { 1118 OT::GPOS::position_finish_offsets (font, buffer); 1119 } 1120 1121 /** 1122 * hb_ot_layout_get_size_params: 1123 * 1124 * Since: 0.9.10 1125 **/ 1126 hb_bool_t 1127 hb_ot_layout_get_size_params (hb_face_t *face, 1128 unsigned int *design_size, /* OUT. May be NULL */ 1129 unsigned int *subfamily_id, /* OUT. May be NULL */ 1130 hb_ot_name_id_t *subfamily_name_id, /* OUT. May be NULL */ 1131 unsigned int *range_start, /* OUT. May be NULL */ 1132 unsigned int *range_end /* OUT. May be NULL */) 1133 { 1134 const OT::GPOS &gpos = *face->table.GPOS->table; 1135 const hb_tag_t tag = HB_TAG ('s','i','z','e'); 1136 1137 unsigned int num_features = gpos.get_feature_count (); 1138 for (unsigned int i = 0; i < num_features; i++) 1139 { 1140 if (tag == gpos.get_feature_tag (i)) 1141 { 1142 const OT::Feature &f = gpos.get_feature (i); 1143 const OT::FeatureParamsSize ¶ms = f.get_feature_params ().get_size_params (tag); 1144 1145 if (params.designSize) 1146 { 1147 if (design_size) *design_size = params.designSize; 1148 if (subfamily_id) *subfamily_id = params.subfamilyID; 1149 if (subfamily_name_id) *subfamily_name_id = params.subfamilyNameID; 1150 if (range_start) *range_start = params.rangeStart; 1151 if (range_end) *range_end = params.rangeEnd; 1152 1153 return true; 1154 } 1155 } 1156 } 1157 1158 if (design_size) *design_size = 0; 1159 if (subfamily_id) *subfamily_id = 0; 1160 if (subfamily_name_id) *subfamily_name_id = HB_OT_NAME_ID_INVALID; 1161 if (range_start) *range_start = 0; 1162 if (range_end) *range_end = 0; 1163 1164 return false; 1165 } 1166 1167 /** 1168 * hb_ot_layout_feature_get_name_ids: 1169 * @face: #hb_face_t to work upon 1170 * @table_tag: table tag to query, "GSUB" or "GPOS". 1171 * @feature_index: index of feature to query. 1172 * @label_id: (out) (allow-none): The name table name ID that specifies a string 1173 * for a user-interface label for this feature. (May be NULL.) 1174 * @tooltip_id: (out) (allow-none): The name table name ID that specifies a string 1175 * that an application can use for tooltip text for this 1176 * feature. (May be NULL.) 1177 * @sample_id: (out) (allow-none): The name table name ID that specifies sample text 1178 * that illustrates the effect of this feature. (May be NULL.) 1179 * @num_named_parameters: (out) (allow-none): Number of named parameters. (May be zero.) 1180 * @first_param_id: (out) (allow-none): The first name table name ID used to specify 1181 * strings for user-interface labels for the feature 1182 * parameters. (Must be zero if numParameters is zero.) 1183 * 1184 * Fetches name indices from feature parameters for "Stylistic Set" ('ssXX') or 1185 * "Character Variant" ('cvXX') features. 1186 * 1187 * Return value: true if data found, false otherwise 1188 * 1189 * Since: 2.0.0 1190 **/ 1191 hb_bool_t 1192 hb_ot_layout_feature_get_name_ids (hb_face_t *face, 1193 hb_tag_t table_tag, 1194 unsigned int feature_index, 1195 hb_ot_name_id_t *label_id, /* OUT. May be NULL */ 1196 hb_ot_name_id_t *tooltip_id, /* OUT. May be NULL */ 1197 hb_ot_name_id_t *sample_id, /* OUT. May be NULL */ 1198 unsigned int *num_named_parameters, /* OUT. May be NULL */ 1199 hb_ot_name_id_t *first_param_id /* OUT. May be NULL */) 1200 { 1201 const OT::GSUBGPOS &g = get_gsubgpos_table (face, table_tag); 1202 1203 hb_tag_t feature_tag = g.get_feature_tag (feature_index); 1204 const OT::Feature &f = g.get_feature (feature_index); 1205 1206 const OT::FeatureParams &feature_params = f.get_feature_params (); 1207 if (&feature_params != &Null (OT::FeatureParams)) 1208 { 1209 const OT::FeatureParamsStylisticSet& ss_params = 1210 feature_params.get_stylistic_set_params (feature_tag); 1211 if (&ss_params != &Null (OT::FeatureParamsStylisticSet)) /* ssXX */ 1212 { 1213 if (label_id) *label_id = ss_params.uiNameID; 1214 // ssXX features don't have the rest 1215 if (tooltip_id) *tooltip_id = HB_OT_NAME_ID_INVALID; 1216 if (sample_id) *sample_id = HB_OT_NAME_ID_INVALID; 1217 if (num_named_parameters) *num_named_parameters = 0; 1218 if (first_param_id) *first_param_id = HB_OT_NAME_ID_INVALID; 1219 return true; 1220 } 1221 const OT::FeatureParamsCharacterVariants& cv_params = 1222 feature_params.get_character_variants_params (feature_tag); 1223 if (&cv_params != &Null (OT::FeatureParamsCharacterVariants)) /* cvXX */ 1224 { 1225 if (label_id) *label_id = cv_params.featUILableNameID; 1226 if (tooltip_id) *tooltip_id = cv_params.featUITooltipTextNameID; 1227 if (sample_id) *sample_id = cv_params.sampleTextNameID; 1228 if (num_named_parameters) *num_named_parameters = cv_params.numNamedParameters; 1229 if (first_param_id) *first_param_id = cv_params.firstParamUILabelNameID; 1230 return true; 1231 } 1232 } 1233 1234 if (label_id) *label_id = HB_OT_NAME_ID_INVALID; 1235 if (tooltip_id) *tooltip_id = HB_OT_NAME_ID_INVALID; 1236 if (sample_id) *sample_id = HB_OT_NAME_ID_INVALID; 1237 if (num_named_parameters) *num_named_parameters = 0; 1238 if (first_param_id) *first_param_id = HB_OT_NAME_ID_INVALID; 1239 return false; 1240 } 1241 1242 /** 1243 * hb_ot_layout_feature_get_characters: 1244 * @face: #hb_face_t to work upon 1245 * @table_tag: table tag to query, "GSUB" or "GPOS". 1246 * @feature_index: index of feature to query. 1247 * @start_offset: In case the resulting char_count was equal to its input value, there 1248 * is a chance there were more characters on the tag so this API can be 1249 * called with an offset till resulting char_count gets to a number 1250 * lower than input buffer (or consider using just a bigger buffer for 1251 * one shot copying). 1252 * @char_count: (inout) (allow-none): The count of characters for which this feature 1253 * provides glyph variants. (May be zero.) 1254 * @characters: (out caller-allocates) (array length=char_count): A buffer pointer. The Unicode codepoints 1255 * of the characters for which this feature provides glyph variants. 1256 * 1257 * Fetches characters listed by designer under feature parameters for "Character 1258 * Variant" ("cvXX") features. 1259 * 1260 * Return value: Number of total sample characters in the cvXX feature. 1261 * 1262 * Since: 2.0.0 1263 **/ 1264 unsigned int 1265 hb_ot_layout_feature_get_characters (hb_face_t *face, 1266 hb_tag_t table_tag, 1267 unsigned int feature_index, 1268 unsigned int start_offset, 1269 unsigned int *char_count, /* IN/OUT. May be NULL */ 1270 hb_codepoint_t *characters /* OUT. May be NULL */) 1271 { 1272 const OT::GSUBGPOS &g = get_gsubgpos_table (face, table_tag); 1273 1274 hb_tag_t feature_tag = g.get_feature_tag (feature_index); 1275 const OT::Feature &f = g.get_feature (feature_index); 1276 1277 const OT::FeatureParams &feature_params = f.get_feature_params (); 1278 1279 const OT::FeatureParamsCharacterVariants& cv_params = 1280 feature_params.get_character_variants_params(feature_tag); 1281 1282 unsigned int len = 0; 1283 if (char_count && characters && start_offset < cv_params.characters.len) 1284 { 1285 len = MIN (cv_params.characters.len - start_offset, *char_count); 1286 for (unsigned int i = 0; i < len; ++i) 1287 characters[i] = cv_params.characters[start_offset + i]; 1288 } 1289 if (char_count) *char_count = len; 1290 return cv_params.characters.len; 1291 } 1292 1293 1294 /* 1295 * Parts of different types are implemented here such that they have direct 1296 * access to GSUB/GPOS lookups. 1297 */ 1298 1299 1300 struct GSUBProxy 1301 { 1302 enum { table_index = 0 }; 1303 enum { inplace = false }; 1304 typedef OT::SubstLookup Lookup; 1305 1306 GSUBProxy (hb_face_t *face) : 1307 table (*face->table.GSUB->table), 1308 accels (face->table.GSUB->accels) {} 1309 1310 const OT::GSUB &table; 1311 const OT::hb_ot_layout_lookup_accelerator_t *accels; 1312 }; 1313 1314 struct GPOSProxy 1315 { 1316 enum { table_index = 1 }; 1317 enum { inplace = true }; 1318 typedef OT::PosLookup Lookup; 1319 1320 GPOSProxy (hb_face_t *face) : 1321 table (*face->table.GPOS->table), 1322 accels (face->table.GPOS->accels) {} 1323 1324 const OT::GPOS &table; 1325 const OT::hb_ot_layout_lookup_accelerator_t *accels; 1326 }; 1327 1328 1329 static inline bool 1330 apply_forward (OT::hb_ot_apply_context_t *c, 1331 const OT::hb_ot_layout_lookup_accelerator_t &accel) 1332 { 1333 bool ret = false; 1334 hb_buffer_t *buffer = c->buffer; 1335 while (buffer->idx < buffer->len && buffer->successful) 1336 { 1337 bool applied = false; 1338 if (accel.may_have (buffer->cur().codepoint) && 1339 (buffer->cur().mask & c->lookup_mask) && 1340 c->check_glyph_property (&buffer->cur(), c->lookup_props)) 1341 { 1342 applied = accel.apply (c); 1343 } 1344 1345 if (applied) 1346 ret = true; 1347 else 1348 buffer->next_glyph (); 1349 } 1350 return ret; 1351 } 1352 1353 static inline bool 1354 apply_backward (OT::hb_ot_apply_context_t *c, 1355 const OT::hb_ot_layout_lookup_accelerator_t &accel) 1356 { 1357 bool ret = false; 1358 hb_buffer_t *buffer = c->buffer; 1359 do 1360 { 1361 if (accel.may_have (buffer->cur().codepoint) && 1362 (buffer->cur().mask & c->lookup_mask) && 1363 c->check_glyph_property (&buffer->cur(), c->lookup_props)) 1364 ret |= accel.apply (c); 1365 1366 /* The reverse lookup doesn't "advance" cursor (for good reason). */ 1367 buffer->idx--; 1368 1369 } 1370 while ((int) buffer->idx >= 0); 1371 return ret; 1372 } 1373 1374 template <typename Proxy> 1375 static inline void 1376 apply_string (OT::hb_ot_apply_context_t *c, 1377 const typename Proxy::Lookup &lookup, 1378 const OT::hb_ot_layout_lookup_accelerator_t &accel) 1379 { 1380 hb_buffer_t *buffer = c->buffer; 1381 1382 if (unlikely (!buffer->len || !c->lookup_mask)) 1383 return; 1384 1385 c->set_lookup_props (lookup.get_props ()); 1386 1387 if (likely (!lookup.is_reverse ())) 1388 { 1389 /* in/out forward substitution/positioning */ 1390 if (Proxy::table_index == 0) 1391 buffer->clear_output (); 1392 buffer->idx = 0; 1393 1394 bool ret; 1395 ret = apply_forward (c, accel); 1396 if (ret) 1397 { 1398 if (!Proxy::inplace) 1399 buffer->swap_buffers (); 1400 else 1401 assert (!buffer->has_separate_output ()); 1402 } 1403 } 1404 else 1405 { 1406 /* in-place backward substitution/positioning */ 1407 if (Proxy::table_index == 0) 1408 buffer->remove_output (); 1409 buffer->idx = buffer->len - 1; 1410 1411 apply_backward (c, accel); 1412 } 1413 } 1414 1415 template <typename Proxy> 1416 inline void hb_ot_map_t::apply (const Proxy &proxy, 1417 const hb_ot_shape_plan_t *plan, 1418 hb_font_t *font, 1419 hb_buffer_t *buffer) const 1420 { 1421 const unsigned int table_index = proxy.table_index; 1422 unsigned int i = 0; 1423 OT::hb_ot_apply_context_t c (table_index, font, buffer); 1424 c.set_recurse_func (Proxy::Lookup::apply_recurse_func); 1425 1426 for (unsigned int stage_index = 0; stage_index < stages[table_index].len; stage_index++) { 1427 const stage_map_t *stage = &stages[table_index][stage_index]; 1428 for (; i < stage->last_lookup; i++) 1429 { 1430 unsigned int lookup_index = lookups[table_index][i].index; 1431 if (!buffer->message (font, "start lookup %d", lookup_index)) continue; 1432 c.set_lookup_index (lookup_index); 1433 c.set_lookup_mask (lookups[table_index][i].mask); 1434 c.set_auto_zwj (lookups[table_index][i].auto_zwj); 1435 c.set_auto_zwnj (lookups[table_index][i].auto_zwnj); 1436 if (lookups[table_index][i].random) 1437 { 1438 c.set_random (true); 1439 buffer->unsafe_to_break_all (); 1440 } 1441 apply_string<Proxy> (&c, 1442 proxy.table.get_lookup (lookup_index), 1443 proxy.accels[lookup_index]); 1444 (void) buffer->message (font, "end lookup %d", lookup_index); 1445 } 1446 1447 if (stage->pause_func) 1448 { 1449 buffer->clear_output (); 1450 stage->pause_func (plan, font, buffer); 1451 } 1452 } 1453 } 1454 1455 void hb_ot_map_t::substitute (const hb_ot_shape_plan_t *plan, hb_font_t *font, hb_buffer_t *buffer) const 1456 { 1457 GSUBProxy proxy (font->face); 1458 apply (proxy, plan, font, buffer); 1459 } 1460 1461 void hb_ot_map_t::position (const hb_ot_shape_plan_t *plan, hb_font_t *font, hb_buffer_t *buffer) const 1462 { 1463 GPOSProxy proxy (font->face); 1464 apply (proxy, plan, font, buffer); 1465 } 1466 1467 void 1468 hb_ot_layout_substitute_lookup (OT::hb_ot_apply_context_t *c, 1469 const OT::SubstLookup &lookup, 1470 const OT::hb_ot_layout_lookup_accelerator_t &accel) 1471 { 1472 apply_string<GSUBProxy> (c, lookup, accel); 1473 } 1474 1475 #if 0 1476 static const OT::BASE& _get_base (hb_face_t *face) 1477 { 1478 return *face->table.BASE; 1479 } 1480 1481 hb_bool_t 1482 hb_ot_layout_get_baseline (hb_font_t *font, 1483 hb_ot_layout_baseline_t baseline, 1484 hb_direction_t direction, 1485 hb_tag_t script_tag, 1486 hb_tag_t language_tag, 1487 hb_position_t *coord /* OUT. May be NULL. */) 1488 { 1489 const OT::BASE &base = _get_base (font->face); 1490 bool result = base.get_baseline (font, baseline, direction, script_tag, 1491 language_tag, coord); 1492 1493 /* TODO: Simulate https://docs.microsoft.com/en-us/typography/opentype/spec/baselinetags#ideographic-em-box */ 1494 if (!result && coord) *coord = 0; 1495 1496 if (coord) *coord = font->em_scale_dir (*coord, direction); 1497 1498 return result; 1499 } 1500 1501 /* To be moved to public header */ 1502 /* 1503 * BASE 1504 */ 1505 1506 /** 1507 * hb_ot_layout_baseline_t: 1508 * 1509 * https://docs.microsoft.com/en-us/typography/opentype/spec/baselinetags 1510 * 1511 * Since: DONTREPLACEME 1512 */ 1513 typedef enum { 1514 HB_OT_LAYOUT_BASELINE_HANG = HB_TAG('h','a','n','g'), 1515 HB_OT_LAYOUT_BASELINE_ICFB = HB_TAG('i','c','f','b'), 1516 HB_OT_LAYOUT_BASELINE_ICFT = HB_TAG('i','c','f','t'), 1517 HB_OT_LAYOUT_BASELINE_IDEO = HB_TAG('i','d','e','o'), 1518 HB_OT_LAYOUT_BASELINE_IDTB = HB_TAG('i','d','t','b'), 1519 HB_OT_LAYOUT_BASELINE_MATH = HB_TAG('m','a','t','h'), 1520 HB_OT_LAYOUT_BASELINE_ROMN = HB_TAG('r','o','m','n') 1521 } hb_ot_layout_baseline_t; 1522 1523 HB_EXTERN hb_bool_t 1524 hb_ot_layout_get_baseline (hb_font_t *font, 1525 hb_ot_layout_baseline_t baseline, 1526 hb_direction_t direction, 1527 hb_tag_t script_tag, 1528 hb_tag_t language_tag, 1529 hb_position_t *coord /* OUT. May be NULL. */); 1530 1531 #endif 1532
