hb-ot-layout.cc revision fd42257f8c45ff8e036e1c3eb1a788a101be7ead
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 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-ot-layout-private.hh" 32 33#include "hb-ot-layout-gdef-table.hh" 34#include "hb-ot-layout-gsub-table.hh" 35#include "hb-ot-layout-gpos-table.hh" 36#include "hb-ot-maxp-table.hh" 37 38 39#include <stdlib.h> 40#include <string.h> 41 42 43HB_SHAPER_DATA_ENSURE_DECLARE(ot, face) 44 45static hb_bool_t 46hb_ot_layout_ensure (hb_face_t *face) 47{ 48 return hb_ot_shaper_face_data_ensure (face); 49} 50 51 52hb_ot_layout_t * 53_hb_ot_layout_create (hb_face_t *face) 54{ 55 hb_ot_layout_t *layout = (hb_ot_layout_t *) calloc (1, sizeof (hb_ot_layout_t)); 56 57 layout->gdef_blob = Sanitizer<GDEF>::sanitize (hb_face_reference_table (face, HB_OT_TAG_GDEF)); 58 layout->gdef = Sanitizer<GDEF>::lock_instance (layout->gdef_blob); 59 60 layout->gsub_blob = Sanitizer<GSUB>::sanitize (hb_face_reference_table (face, HB_OT_TAG_GSUB)); 61 layout->gsub = Sanitizer<GSUB>::lock_instance (layout->gsub_blob); 62 63 layout->gpos_blob = Sanitizer<GPOS>::sanitize (hb_face_reference_table (face, HB_OT_TAG_GPOS)); 64 layout->gpos = Sanitizer<GPOS>::lock_instance (layout->gpos_blob); 65 66 return layout; 67} 68 69void 70_hb_ot_layout_destroy (hb_ot_layout_t *layout) 71{ 72 hb_blob_destroy (layout->gdef_blob); 73 hb_blob_destroy (layout->gsub_blob); 74 hb_blob_destroy (layout->gpos_blob); 75 76 free (layout); 77} 78 79static inline const GDEF& 80_get_gdef (hb_face_t *face) 81{ 82 if (unlikely (!hb_ot_layout_ensure (face))) return Null(GDEF); 83 return *hb_ot_layout_from_face (face)->gdef; 84} 85static inline const GSUB& 86_get_gsub (hb_face_t *face) 87{ 88 if (unlikely (!hb_ot_layout_ensure (face))) return Null(GSUB); 89 return *hb_ot_layout_from_face (face)->gsub; 90} 91static inline const GPOS& 92_get_gpos (hb_face_t *face) 93{ 94 if (unlikely (!hb_ot_layout_ensure (face))) return Null(GPOS); 95 return *hb_ot_layout_from_face (face)->gpos; 96} 97 98 99/* 100 * GDEF 101 */ 102 103hb_bool_t 104hb_ot_layout_has_glyph_classes (hb_face_t *face) 105{ 106 return _get_gdef (face).has_glyph_classes (); 107} 108 109static inline unsigned int 110_hb_ot_layout_get_glyph_property (hb_face_t *face, 111 hb_glyph_info_t *info) 112{ 113 if (!info->props_cache()) 114 { 115 info->props_cache() = hb_ot_layout_from_face (face)->gdef->get_glyph_props (info->codepoint); 116 } 117 118 return info->props_cache(); 119} 120 121static inline hb_bool_t 122_hb_ot_layout_match_properties_mark (hb_face_t *face, 123 hb_codepoint_t glyph, 124 unsigned int glyph_props, 125 unsigned int lookup_props) 126{ 127 /* If using mark filtering sets, the high short of 128 * lookup_props has the set index. 129 */ 130 if (lookup_props & LookupFlag::UseMarkFilteringSet) 131 return hb_ot_layout_from_face (face)->gdef->mark_set_covers (lookup_props >> 16, glyph); 132 133 /* The second byte of lookup_props has the meaning 134 * "ignore marks of attachment type different than 135 * the attachment type specified." 136 */ 137 if (lookup_props & LookupFlag::MarkAttachmentType) 138 return (lookup_props & LookupFlag::MarkAttachmentType) == (glyph_props & LookupFlag::MarkAttachmentType); 139 140 return true; 141} 142 143static inline hb_bool_t 144_hb_ot_layout_match_properties (hb_face_t *face, 145 hb_codepoint_t glyph, 146 unsigned int glyph_props, 147 unsigned int lookup_props) 148{ 149 /* Not covered, if, for example, glyph class is ligature and 150 * lookup_props includes LookupFlags::IgnoreLigatures 151 */ 152 if (glyph_props & lookup_props & LookupFlag::IgnoreFlags) 153 return false; 154 155 if (unlikely (glyph_props & HB_OT_LAYOUT_GLYPH_CLASS_MARK)) 156 return _hb_ot_layout_match_properties_mark (face, glyph, glyph_props, lookup_props); 157 158 return true; 159} 160 161hb_bool_t 162_hb_ot_layout_check_glyph_property (hb_face_t *face, 163 hb_glyph_info_t *ginfo, 164 unsigned int lookup_props, 165 unsigned int *property_out) 166{ 167 unsigned int property; 168 169 property = _hb_ot_layout_get_glyph_property (face, ginfo); 170 *property_out = property; 171 172 return _hb_ot_layout_match_properties (face, ginfo->codepoint, property, lookup_props); 173} 174 175hb_bool_t 176_hb_ot_layout_skip_mark (hb_face_t *face, 177 hb_glyph_info_t *ginfo, 178 unsigned int lookup_props, 179 unsigned int *property_out) 180{ 181 unsigned int property; 182 183 property = _hb_ot_layout_get_glyph_property (face, ginfo); 184 if (property_out) 185 *property_out = property; 186 187 /* If it's a mark, skip it if we don't accept it. */ 188 if (unlikely (property & HB_OT_LAYOUT_GLYPH_CLASS_MARK)) 189 return !_hb_ot_layout_match_properties (face, ginfo->codepoint, property, lookup_props); 190 191 /* If not a mark, don't skip. */ 192 return false; 193} 194 195 196 197unsigned int 198hb_ot_layout_get_attach_points (hb_face_t *face, 199 hb_codepoint_t glyph, 200 unsigned int start_offset, 201 unsigned int *point_count /* IN/OUT */, 202 unsigned int *point_array /* OUT */) 203{ 204 return _get_gdef (face).get_attach_points (glyph, start_offset, point_count, point_array); 205} 206 207unsigned int 208hb_ot_layout_get_ligature_carets (hb_font_t *font, 209 hb_direction_t direction, 210 hb_codepoint_t glyph, 211 unsigned int start_offset, 212 unsigned int *caret_count /* IN/OUT */, 213 int *caret_array /* OUT */) 214{ 215 return _get_gdef (font->face).get_lig_carets (font, direction, glyph, start_offset, caret_count, caret_array); 216} 217 218/* 219 * GSUB/GPOS 220 */ 221 222static const GSUBGPOS& 223get_gsubgpos_table (hb_face_t *face, 224 hb_tag_t table_tag) 225{ 226 switch (table_tag) { 227 case HB_OT_TAG_GSUB: return _get_gsub (face); 228 case HB_OT_TAG_GPOS: return _get_gpos (face); 229 default: return Null(GSUBGPOS); 230 } 231} 232 233 234unsigned int 235hb_ot_layout_table_get_script_tags (hb_face_t *face, 236 hb_tag_t table_tag, 237 unsigned int start_offset, 238 unsigned int *script_count /* IN/OUT */, 239 hb_tag_t *script_tags /* OUT */) 240{ 241 const GSUBGPOS &g = get_gsubgpos_table (face, table_tag); 242 243 return g.get_script_tags (start_offset, script_count, script_tags); 244} 245 246hb_bool_t 247hb_ot_layout_table_find_script (hb_face_t *face, 248 hb_tag_t table_tag, 249 hb_tag_t script_tag, 250 unsigned int *script_index) 251{ 252 ASSERT_STATIC (Index::NOT_FOUND_INDEX == HB_OT_LAYOUT_NO_SCRIPT_INDEX); 253 const GSUBGPOS &g = get_gsubgpos_table (face, table_tag); 254 255 if (g.find_script_index (script_tag, script_index)) 256 return true; 257 258 /* try finding 'DFLT' */ 259 if (g.find_script_index (HB_OT_TAG_DEFAULT_SCRIPT, script_index)) 260 return false; 261 262 /* try with 'dflt'; MS site has had typos and many fonts use it now :(. 263 * including many versions of DejaVu Sans Mono! */ 264 if (g.find_script_index (HB_OT_TAG_DEFAULT_LANGUAGE, script_index)) 265 return false; 266 267 if (script_index) *script_index = HB_OT_LAYOUT_NO_SCRIPT_INDEX; 268 return false; 269} 270 271hb_bool_t 272hb_ot_layout_table_choose_script (hb_face_t *face, 273 hb_tag_t table_tag, 274 const hb_tag_t *script_tags, 275 unsigned int *script_index, 276 hb_tag_t *chosen_script) 277{ 278 ASSERT_STATIC (Index::NOT_FOUND_INDEX == HB_OT_LAYOUT_NO_SCRIPT_INDEX); 279 const GSUBGPOS &g = get_gsubgpos_table (face, table_tag); 280 281 while (*script_tags) 282 { 283 if (g.find_script_index (*script_tags, script_index)) { 284 if (chosen_script) 285 *chosen_script = *script_tags; 286 return true; 287 } 288 script_tags++; 289 } 290 291 /* try finding 'DFLT' */ 292 if (g.find_script_index (HB_OT_TAG_DEFAULT_SCRIPT, script_index)) { 293 if (chosen_script) 294 *chosen_script = HB_OT_TAG_DEFAULT_SCRIPT; 295 return false; 296 } 297 298 /* try with 'dflt'; MS site has had typos and many fonts use it now :( */ 299 if (g.find_script_index (HB_OT_TAG_DEFAULT_LANGUAGE, script_index)) { 300 if (chosen_script) 301 *chosen_script = HB_OT_TAG_DEFAULT_LANGUAGE; 302 return false; 303 } 304 305 /* try with 'latn'; some old fonts put their features there even though 306 they're really trying to support Thai, for example :( */ 307#define HB_OT_TAG_LATIN_SCRIPT HB_TAG ('l', 'a', 't', 'n') 308 if (g.find_script_index (HB_OT_TAG_LATIN_SCRIPT, script_index)) { 309 if (chosen_script) 310 *chosen_script = HB_OT_TAG_LATIN_SCRIPT; 311 return false; 312 } 313 314 if (script_index) *script_index = HB_OT_LAYOUT_NO_SCRIPT_INDEX; 315 if (chosen_script) 316 *chosen_script = HB_OT_LAYOUT_NO_SCRIPT_INDEX; 317 return false; 318} 319 320unsigned int 321hb_ot_layout_table_get_feature_tags (hb_face_t *face, 322 hb_tag_t table_tag, 323 unsigned int start_offset, 324 unsigned int *feature_count /* IN/OUT */, 325 hb_tag_t *feature_tags /* OUT */) 326{ 327 const GSUBGPOS &g = get_gsubgpos_table (face, table_tag); 328 329 return g.get_feature_tags (start_offset, feature_count, feature_tags); 330} 331 332 333unsigned int 334hb_ot_layout_script_get_language_tags (hb_face_t *face, 335 hb_tag_t table_tag, 336 unsigned int script_index, 337 unsigned int start_offset, 338 unsigned int *language_count /* IN/OUT */, 339 hb_tag_t *language_tags /* OUT */) 340{ 341 const Script &s = get_gsubgpos_table (face, table_tag).get_script (script_index); 342 343 return s.get_lang_sys_tags (start_offset, language_count, language_tags); 344} 345 346hb_bool_t 347hb_ot_layout_script_find_language (hb_face_t *face, 348 hb_tag_t table_tag, 349 unsigned int script_index, 350 hb_tag_t language_tag, 351 unsigned int *language_index) 352{ 353 ASSERT_STATIC (Index::NOT_FOUND_INDEX == HB_OT_LAYOUT_DEFAULT_LANGUAGE_INDEX); 354 const Script &s = get_gsubgpos_table (face, table_tag).get_script (script_index); 355 356 if (s.find_lang_sys_index (language_tag, language_index)) 357 return true; 358 359 /* try with 'dflt'; MS site has had typos and many fonts use it now :( */ 360 if (s.find_lang_sys_index (HB_OT_TAG_DEFAULT_LANGUAGE, language_index)) 361 return false; 362 363 if (language_index) *language_index = HB_OT_LAYOUT_DEFAULT_LANGUAGE_INDEX; 364 return false; 365} 366 367hb_bool_t 368hb_ot_layout_language_get_required_feature_index (hb_face_t *face, 369 hb_tag_t table_tag, 370 unsigned int script_index, 371 unsigned int language_index, 372 unsigned int *feature_index) 373{ 374 const LangSys &l = get_gsubgpos_table (face, table_tag).get_script (script_index).get_lang_sys (language_index); 375 376 if (feature_index) *feature_index = l.get_required_feature_index (); 377 378 return l.has_required_feature (); 379} 380 381unsigned int 382hb_ot_layout_language_get_feature_indexes (hb_face_t *face, 383 hb_tag_t table_tag, 384 unsigned int script_index, 385 unsigned int language_index, 386 unsigned int start_offset, 387 unsigned int *feature_count /* IN/OUT */, 388 unsigned int *feature_indexes /* OUT */) 389{ 390 const GSUBGPOS &g = get_gsubgpos_table (face, table_tag); 391 const LangSys &l = g.get_script (script_index).get_lang_sys (language_index); 392 393 return l.get_feature_indexes (start_offset, feature_count, feature_indexes); 394} 395 396unsigned int 397hb_ot_layout_language_get_feature_tags (hb_face_t *face, 398 hb_tag_t table_tag, 399 unsigned int script_index, 400 unsigned int language_index, 401 unsigned int start_offset, 402 unsigned int *feature_count /* IN/OUT */, 403 hb_tag_t *feature_tags /* OUT */) 404{ 405 const GSUBGPOS &g = get_gsubgpos_table (face, table_tag); 406 const LangSys &l = g.get_script (script_index).get_lang_sys (language_index); 407 408 ASSERT_STATIC (sizeof (unsigned int) == sizeof (hb_tag_t)); 409 unsigned int ret = l.get_feature_indexes (start_offset, feature_count, (unsigned int *) feature_tags); 410 411 if (feature_tags) { 412 unsigned int count = *feature_count; 413 for (unsigned int i = 0; i < count; i++) 414 feature_tags[i] = g.get_feature_tag ((unsigned int) feature_tags[i]); 415 } 416 417 return ret; 418} 419 420 421hb_bool_t 422hb_ot_layout_language_find_feature (hb_face_t *face, 423 hb_tag_t table_tag, 424 unsigned int script_index, 425 unsigned int language_index, 426 hb_tag_t feature_tag, 427 unsigned int *feature_index) 428{ 429 ASSERT_STATIC (Index::NOT_FOUND_INDEX == HB_OT_LAYOUT_NO_FEATURE_INDEX); 430 const GSUBGPOS &g = get_gsubgpos_table (face, table_tag); 431 const LangSys &l = g.get_script (script_index).get_lang_sys (language_index); 432 433 unsigned int num_features = l.get_feature_count (); 434 for (unsigned int i = 0; i < num_features; i++) { 435 unsigned int f_index = l.get_feature_index (i); 436 437 if (feature_tag == g.get_feature_tag (f_index)) { 438 if (feature_index) *feature_index = f_index; 439 return true; 440 } 441 } 442 443 if (feature_index) *feature_index = HB_OT_LAYOUT_NO_FEATURE_INDEX; 444 return false; 445} 446 447unsigned int 448hb_ot_layout_feature_get_lookup_indexes (hb_face_t *face, 449 hb_tag_t table_tag, 450 unsigned int feature_index, 451 unsigned int start_offset, 452 unsigned int *lookup_count /* IN/OUT */, 453 unsigned int *lookup_indexes /* OUT */) 454{ 455 const GSUBGPOS &g = get_gsubgpos_table (face, table_tag); 456 const Feature &f = g.get_feature (feature_index); 457 458 return f.get_lookup_indexes (start_offset, lookup_count, lookup_indexes); 459} 460 461 462/* 463 * GSUB 464 */ 465 466hb_bool_t 467hb_ot_layout_has_substitution (hb_face_t *face) 468{ 469 return &_get_gsub (face) != &Null(GSUB); 470} 471 472hb_bool_t 473hb_ot_layout_would_substitute_lookup (hb_face_t *face, 474 const hb_codepoint_t *glyphs, 475 unsigned int glyphs_length, 476 unsigned int lookup_index) 477{ 478 if (unlikely (glyphs_length < 1 || glyphs_length > 2)) return false; 479 hb_would_apply_context_t c (face, glyphs[0], glyphs_length == 2 ? glyphs[1] : -1); 480 return _get_gsub (face).would_substitute_lookup (&c, lookup_index); 481} 482 483hb_bool_t 484hb_ot_layout_would_substitute_lookup_fast (hb_face_t *face, 485 const hb_codepoint_t *glyphs, 486 unsigned int glyphs_length, 487 unsigned int lookup_index) 488{ 489 if (unlikely (glyphs_length < 1 || glyphs_length > 2)) return false; 490 hb_would_apply_context_t c (face, glyphs[0], glyphs_length == 2 ? glyphs[1] : -1); 491 return hb_ot_layout_from_face (face)->gsub->would_substitute_lookup (&c, lookup_index); 492} 493 494void 495hb_ot_layout_substitute_start (hb_buffer_t *buffer) 496{ 497 GSUB::substitute_start (buffer); 498} 499 500hb_bool_t 501hb_ot_layout_substitute_lookup (hb_face_t *face, 502 hb_buffer_t *buffer, 503 unsigned int lookup_index, 504 hb_mask_t mask) 505{ 506 hb_apply_context_t c (NULL, face, buffer, mask); 507 return _get_gsub (face).substitute_lookup (&c, lookup_index); 508} 509 510hb_bool_t 511hb_ot_layout_substitute_lookup_fast (hb_face_t *face, 512 hb_buffer_t *buffer, 513 unsigned int lookup_index, 514 hb_mask_t mask) 515{ 516 hb_apply_context_t c (NULL, face, buffer, mask); 517 return hb_ot_layout_from_face (face)->gsub->substitute_lookup (&c, lookup_index); 518} 519 520void 521hb_ot_layout_substitute_finish (hb_buffer_t *buffer HB_UNUSED) 522{ 523 GSUB::substitute_finish (buffer); 524} 525 526void 527hb_ot_layout_substitute_closure_lookup (hb_face_t *face, 528 hb_set_t *glyphs, 529 unsigned int lookup_index) 530{ 531 hb_closure_context_t c (face, glyphs); 532 _get_gsub (face).closure_lookup (&c, lookup_index); 533} 534 535/* 536 * GPOS 537 */ 538 539hb_bool_t 540hb_ot_layout_has_positioning (hb_face_t *face) 541{ 542 return &_get_gpos (face) != &Null(GPOS); 543} 544 545void 546hb_ot_layout_position_start (hb_buffer_t *buffer) 547{ 548 GPOS::position_start (buffer); 549} 550 551hb_bool_t 552hb_ot_layout_position_lookup (hb_font_t *font, 553 hb_buffer_t *buffer, 554 unsigned int lookup_index, 555 hb_mask_t mask) 556{ 557 hb_apply_context_t c (font, font->face, buffer, mask); 558 return _get_gpos (font->face).position_lookup (&c, lookup_index); 559} 560 561hb_bool_t 562hb_ot_layout_position_lookup_fast (hb_font_t *font, 563 hb_buffer_t *buffer, 564 unsigned int lookup_index, 565 hb_mask_t mask) 566{ 567 hb_apply_context_t c (font, font->face, buffer, mask); 568 return hb_ot_layout_from_face (font->face)->gpos->position_lookup (&c, lookup_index); 569} 570 571void 572hb_ot_layout_position_finish (hb_buffer_t *buffer) 573{ 574 GPOS::position_finish (buffer); 575} 576 577 578