hb-ot-layout.cc revision 578e42182b9b9cf15b4c5426fae36e224160cbd7
1/* 2 * Copyright © 1998-2004 David Turner and Werner Lemberg 3 * Copyright © 2006 Behdad Esfahbod 4 * Copyright © 2007,2008,2009 Red Hat, Inc. 5 * 6 * This is part of HarfBuzz, a text shaping library. 7 * 8 * Permission is hereby granted, without written agreement and without 9 * license or royalty fees, to use, copy, modify, and distribute this 10 * software and its documentation for any purpose, provided that the 11 * above copyright notice and the following two paragraphs appear in 12 * all copies of this software. 13 * 14 * IN NO EVENT SHALL THE COPYRIGHT HOLDER BE LIABLE TO ANY PARTY FOR 15 * DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES 16 * ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN 17 * IF THE COPYRIGHT HOLDER HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH 18 * DAMAGE. 19 * 20 * THE COPYRIGHT HOLDER SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING, 21 * BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND 22 * FITNESS FOR A PARTICULAR PURPOSE. THE SOFTWARE PROVIDED HEREUNDER IS 23 * ON AN "AS IS" BASIS, AND THE COPYRIGHT HOLDER HAS NO OBLIGATION TO 24 * PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS. 25 * 26 * Red Hat Author(s): Behdad Esfahbod 27 */ 28 29#include "hb-ot-layout-private.hh" 30 31#include "hb-ot-layout-gdef-table.hh" 32#include "hb-ot-layout-gsub-table.hh" 33#include "hb-ot-layout-gpos-table.hh" 34#include "hb-ot-maxp-table.hh" 35 36 37#include <stdlib.h> 38#include <string.h> 39 40 41HB_SHAPER_DATA_ENSURE_DECLARE(ot, face) 42hb_bool_t 43hb_ot_layout_ensure (hb_face_t *face) 44{ 45 return hb_ot_shaper_face_data_ensure (face); 46} 47 48 49hb_ot_layout_t * 50_hb_ot_layout_create (hb_face_t *face) 51{ 52 hb_ot_layout_t *layout = (hb_ot_layout_t *) calloc (1, sizeof (hb_ot_layout_t)); 53 54 layout->gdef_blob = Sanitizer<GDEF>::sanitize (hb_face_reference_table (face, HB_OT_TAG_GDEF)); 55 layout->gdef = Sanitizer<GDEF>::lock_instance (layout->gdef_blob); 56 57 layout->gsub_blob = Sanitizer<GSUB>::sanitize (hb_face_reference_table (face, HB_OT_TAG_GSUB)); 58 layout->gsub = Sanitizer<GSUB>::lock_instance (layout->gsub_blob); 59 60 layout->gpos_blob = Sanitizer<GPOS>::sanitize (hb_face_reference_table (face, HB_OT_TAG_GPOS)); 61 layout->gpos = Sanitizer<GPOS>::lock_instance (layout->gpos_blob); 62 63 return layout; 64} 65 66void 67_hb_ot_layout_destroy (hb_ot_layout_t *layout) 68{ 69 hb_blob_destroy (layout->gdef_blob); 70 hb_blob_destroy (layout->gsub_blob); 71 hb_blob_destroy (layout->gpos_blob); 72 73 free (layout); 74} 75 76static inline const GDEF& 77_get_gdef (hb_face_t *face) 78{ 79 /* XXX ensure ot_layout, and speed up */ 80 return *hb_ot_layout_from_face (face)->gdef; 81} 82static inline const GSUB& 83_get_gsub (hb_face_t *face) 84{ 85 /* XXX ensure ot_layout, and speed up */ 86 return *hb_ot_layout_from_face (face)->gsub; 87} 88static inline const GPOS& 89_get_gpos (hb_face_t *face) 90{ 91 /* XXX ensure ot_layout, and speed up */ 92 return *hb_ot_layout_from_face (face)->gpos; 93} 94 95 96/* 97 * GDEF 98 */ 99 100hb_bool_t 101hb_ot_layout_has_glyph_classes (hb_face_t *face) 102{ 103 return _get_gdef (face).has_glyph_classes (); 104} 105 106static inline unsigned int 107_hb_ot_layout_get_glyph_property (hb_face_t *face, 108 hb_glyph_info_t *info) 109{ 110 if (!info->props_cache()) 111 { 112 const GDEF &gdef = _get_gdef (face); 113 info->props_cache() = gdef.get_glyph_props (info->codepoint); 114 } 115 116 return info->props_cache(); 117} 118 119static inline hb_bool_t 120_hb_ot_layout_match_properties_mark (hb_face_t *face, 121 hb_codepoint_t glyph, 122 unsigned int glyph_props, 123 unsigned int lookup_props) 124{ 125 /* If using mark filtering sets, the high short of 126 * lookup_props has the set index. 127 */ 128 if (lookup_props & LookupFlag::UseMarkFilteringSet) 129 return _get_gdef (face).mark_set_covers (lookup_props >> 16, glyph); 130 131 /* The second byte of lookup_props has the meaning 132 * "ignore marks of attachment type different than 133 * the attachment type specified." 134 */ 135 if (lookup_props & LookupFlag::MarkAttachmentType) 136 return (lookup_props & LookupFlag::MarkAttachmentType) == (glyph_props & LookupFlag::MarkAttachmentType); 137 138 return true; 139} 140 141static inline hb_bool_t 142_hb_ot_layout_match_properties (hb_face_t *face, 143 hb_codepoint_t glyph, 144 unsigned int glyph_props, 145 unsigned int lookup_props) 146{ 147 /* Not covered, if, for example, glyph class is ligature and 148 * lookup_props includes LookupFlags::IgnoreLigatures 149 */ 150 if (glyph_props & lookup_props & LookupFlag::IgnoreFlags) 151 return false; 152 153 if (unlikely (glyph_props & HB_OT_LAYOUT_GLYPH_CLASS_MARK)) 154 return _hb_ot_layout_match_properties_mark (face, glyph, glyph_props, lookup_props); 155 156 return true; 157} 158 159hb_bool_t 160_hb_ot_layout_check_glyph_property (hb_face_t *face, 161 hb_glyph_info_t *ginfo, 162 unsigned int lookup_props, 163 unsigned int *property_out) 164{ 165 unsigned int property; 166 167 property = _hb_ot_layout_get_glyph_property (face, ginfo); 168 *property_out = property; 169 170 return _hb_ot_layout_match_properties (face, ginfo->codepoint, property, lookup_props); 171} 172 173hb_bool_t 174_hb_ot_layout_skip_mark (hb_face_t *face, 175 hb_glyph_info_t *ginfo, 176 unsigned int lookup_props, 177 unsigned int *property_out) 178{ 179 unsigned int property; 180 181 property = _hb_ot_layout_get_glyph_property (face, ginfo); 182 if (property_out) 183 *property_out = property; 184 185 /* If it's a mark, skip it if we don't accept it. */ 186 if (unlikely (property & HB_OT_LAYOUT_GLYPH_CLASS_MARK)) 187 return !_hb_ot_layout_match_properties (face, ginfo->codepoint, property, lookup_props); 188 189 /* If not a mark, don't skip. */ 190 return false; 191} 192 193 194 195unsigned int 196hb_ot_layout_get_attach_points (hb_face_t *face, 197 hb_codepoint_t glyph, 198 unsigned int start_offset, 199 unsigned int *point_count /* IN/OUT */, 200 unsigned int *point_array /* OUT */) 201{ 202 return _get_gdef (face).get_attach_points (glyph, start_offset, point_count, point_array); 203} 204 205unsigned int 206hb_ot_layout_get_ligature_carets (hb_font_t *font, 207 hb_direction_t direction, 208 hb_codepoint_t glyph, 209 unsigned int start_offset, 210 unsigned int *caret_count /* IN/OUT */, 211 int *caret_array /* OUT */) 212{ 213 return _get_gdef (font->face).get_lig_carets (font, direction, glyph, start_offset, caret_count, caret_array); 214} 215 216/* 217 * GSUB/GPOS 218 */ 219 220static const GSUBGPOS& 221get_gsubgpos_table (hb_face_t *face, 222 hb_tag_t table_tag) 223{ 224 switch (table_tag) { 225 case HB_OT_TAG_GSUB: return _get_gsub (face); 226 case HB_OT_TAG_GPOS: return _get_gpos (face); 227 default: return Null(GSUBGPOS); 228 } 229} 230 231 232unsigned int 233hb_ot_layout_table_get_script_tags (hb_face_t *face, 234 hb_tag_t table_tag, 235 unsigned int start_offset, 236 unsigned int *script_count /* IN/OUT */, 237 hb_tag_t *script_tags /* OUT */) 238{ 239 const GSUBGPOS &g = get_gsubgpos_table (face, table_tag); 240 241 return g.get_script_tags (start_offset, script_count, script_tags); 242} 243 244hb_bool_t 245hb_ot_layout_table_find_script (hb_face_t *face, 246 hb_tag_t table_tag, 247 hb_tag_t script_tag, 248 unsigned int *script_index) 249{ 250 ASSERT_STATIC (Index::NOT_FOUND_INDEX == HB_OT_LAYOUT_NO_SCRIPT_INDEX); 251 const GSUBGPOS &g = get_gsubgpos_table (face, table_tag); 252 253 if (g.find_script_index (script_tag, script_index)) 254 return true; 255 256 /* try finding 'DFLT' */ 257 if (g.find_script_index (HB_OT_TAG_DEFAULT_SCRIPT, script_index)) 258 return false; 259 260 /* try with 'dflt'; MS site has had typos and many fonts use it now :(. 261 * including many versions of DejaVu Sans Mono! */ 262 if (g.find_script_index (HB_OT_TAG_DEFAULT_LANGUAGE, script_index)) 263 return false; 264 265 if (script_index) *script_index = HB_OT_LAYOUT_NO_SCRIPT_INDEX; 266 return false; 267} 268 269hb_bool_t 270hb_ot_layout_table_choose_script (hb_face_t *face, 271 hb_tag_t table_tag, 272 const hb_tag_t *script_tags, 273 unsigned int *script_index, 274 hb_tag_t *chosen_script) 275{ 276 ASSERT_STATIC (Index::NOT_FOUND_INDEX == HB_OT_LAYOUT_NO_SCRIPT_INDEX); 277 const GSUBGPOS &g = get_gsubgpos_table (face, table_tag); 278 279 while (*script_tags) 280 { 281 if (g.find_script_index (*script_tags, script_index)) { 282 if (chosen_script) 283 *chosen_script = *script_tags; 284 return true; 285 } 286 script_tags++; 287 } 288 289 /* try finding 'DFLT' */ 290 if (g.find_script_index (HB_OT_TAG_DEFAULT_SCRIPT, script_index)) { 291 if (chosen_script) 292 *chosen_script = HB_OT_TAG_DEFAULT_SCRIPT; 293 return false; 294 } 295 296 /* try with 'dflt'; MS site has had typos and many fonts use it now :( */ 297 if (g.find_script_index (HB_OT_TAG_DEFAULT_LANGUAGE, script_index)) { 298 if (chosen_script) 299 *chosen_script = HB_OT_TAG_DEFAULT_LANGUAGE; 300 return false; 301 } 302 303 /* try with 'latn'; some old fonts put their features there even though 304 they're really trying to support Thai, for example :( */ 305#define HB_OT_TAG_LATIN_SCRIPT HB_TAG ('l', 'a', 't', 'n') 306 if (g.find_script_index (HB_OT_TAG_LATIN_SCRIPT, script_index)) { 307 if (chosen_script) 308 *chosen_script = HB_OT_TAG_LATIN_SCRIPT; 309 return false; 310 } 311 312 if (script_index) *script_index = HB_OT_LAYOUT_NO_SCRIPT_INDEX; 313 if (chosen_script) 314 *chosen_script = HB_OT_LAYOUT_NO_SCRIPT_INDEX; 315 return false; 316} 317 318unsigned int 319hb_ot_layout_table_get_feature_tags (hb_face_t *face, 320 hb_tag_t table_tag, 321 unsigned int start_offset, 322 unsigned int *feature_count /* IN/OUT */, 323 hb_tag_t *feature_tags /* OUT */) 324{ 325 const GSUBGPOS &g = get_gsubgpos_table (face, table_tag); 326 327 return g.get_feature_tags (start_offset, feature_count, feature_tags); 328} 329 330 331unsigned int 332hb_ot_layout_script_get_language_tags (hb_face_t *face, 333 hb_tag_t table_tag, 334 unsigned int script_index, 335 unsigned int start_offset, 336 unsigned int *language_count /* IN/OUT */, 337 hb_tag_t *language_tags /* OUT */) 338{ 339 const Script &s = get_gsubgpos_table (face, table_tag).get_script (script_index); 340 341 return s.get_lang_sys_tags (start_offset, language_count, language_tags); 342} 343 344hb_bool_t 345hb_ot_layout_script_find_language (hb_face_t *face, 346 hb_tag_t table_tag, 347 unsigned int script_index, 348 hb_tag_t language_tag, 349 unsigned int *language_index) 350{ 351 ASSERT_STATIC (Index::NOT_FOUND_INDEX == HB_OT_LAYOUT_DEFAULT_LANGUAGE_INDEX); 352 const Script &s = get_gsubgpos_table (face, table_tag).get_script (script_index); 353 354 if (s.find_lang_sys_index (language_tag, language_index)) 355 return true; 356 357 /* try with 'dflt'; MS site has had typos and many fonts use it now :( */ 358 if (s.find_lang_sys_index (HB_OT_TAG_DEFAULT_LANGUAGE, language_index)) 359 return false; 360 361 if (language_index) *language_index = HB_OT_LAYOUT_DEFAULT_LANGUAGE_INDEX; 362 return false; 363} 364 365hb_bool_t 366hb_ot_layout_language_get_required_feature_index (hb_face_t *face, 367 hb_tag_t table_tag, 368 unsigned int script_index, 369 unsigned int language_index, 370 unsigned int *feature_index) 371{ 372 const LangSys &l = get_gsubgpos_table (face, table_tag).get_script (script_index).get_lang_sys (language_index); 373 374 if (feature_index) *feature_index = l.get_required_feature_index (); 375 376 return l.has_required_feature (); 377} 378 379unsigned int 380hb_ot_layout_language_get_feature_indexes (hb_face_t *face, 381 hb_tag_t table_tag, 382 unsigned int script_index, 383 unsigned int language_index, 384 unsigned int start_offset, 385 unsigned int *feature_count /* IN/OUT */, 386 unsigned int *feature_indexes /* OUT */) 387{ 388 const GSUBGPOS &g = get_gsubgpos_table (face, table_tag); 389 const LangSys &l = g.get_script (script_index).get_lang_sys (language_index); 390 391 return l.get_feature_indexes (start_offset, feature_count, feature_indexes); 392} 393 394unsigned int 395hb_ot_layout_language_get_feature_tags (hb_face_t *face, 396 hb_tag_t table_tag, 397 unsigned int script_index, 398 unsigned int language_index, 399 unsigned int start_offset, 400 unsigned int *feature_count /* IN/OUT */, 401 hb_tag_t *feature_tags /* OUT */) 402{ 403 const GSUBGPOS &g = get_gsubgpos_table (face, table_tag); 404 const LangSys &l = g.get_script (script_index).get_lang_sys (language_index); 405 406 ASSERT_STATIC (sizeof (unsigned int) == sizeof (hb_tag_t)); 407 unsigned int ret = l.get_feature_indexes (start_offset, feature_count, (unsigned int *) feature_tags); 408 409 if (feature_tags) { 410 unsigned int count = *feature_count; 411 for (unsigned int i = 0; i < count; i++) 412 feature_tags[i] = g.get_feature_tag ((unsigned int) feature_tags[i]); 413 } 414 415 return ret; 416} 417 418 419hb_bool_t 420hb_ot_layout_language_find_feature (hb_face_t *face, 421 hb_tag_t table_tag, 422 unsigned int script_index, 423 unsigned int language_index, 424 hb_tag_t feature_tag, 425 unsigned int *feature_index) 426{ 427 ASSERT_STATIC (Index::NOT_FOUND_INDEX == HB_OT_LAYOUT_NO_FEATURE_INDEX); 428 const GSUBGPOS &g = get_gsubgpos_table (face, table_tag); 429 const LangSys &l = g.get_script (script_index).get_lang_sys (language_index); 430 431 unsigned int num_features = l.get_feature_count (); 432 for (unsigned int i = 0; i < num_features; i++) { 433 unsigned int f_index = l.get_feature_index (i); 434 435 if (feature_tag == g.get_feature_tag (f_index)) { 436 if (feature_index) *feature_index = f_index; 437 return true; 438 } 439 } 440 441 if (feature_index) *feature_index = HB_OT_LAYOUT_NO_FEATURE_INDEX; 442 return false; 443} 444 445unsigned int 446hb_ot_layout_feature_get_lookup_indexes (hb_face_t *face, 447 hb_tag_t table_tag, 448 unsigned int feature_index, 449 unsigned int start_offset, 450 unsigned int *lookup_count /* IN/OUT */, 451 unsigned int *lookup_indexes /* OUT */) 452{ 453 const GSUBGPOS &g = get_gsubgpos_table (face, table_tag); 454 const Feature &f = g.get_feature (feature_index); 455 456 return f.get_lookup_indexes (start_offset, lookup_count, lookup_indexes); 457} 458 459 460/* 461 * GSUB 462 */ 463 464hb_bool_t 465hb_ot_layout_has_substitution (hb_face_t *face) 466{ 467 return &_get_gsub (face) != &Null(GSUB); 468} 469 470hb_bool_t 471hb_ot_layout_would_substitute_lookup (hb_face_t *face, 472 const hb_codepoint_t *glyphs, 473 unsigned int glyphs_length, 474 unsigned int lookup_index) 475{ 476 if (unlikely (glyphs_length < 1 || glyphs_length > 2)) return false; 477 hb_would_apply_context_t c (face, glyphs[0], glyphs_length == 2 ? glyphs[1] : -1); 478 return _get_gsub (face).would_substitute_lookup (&c, lookup_index); 479} 480 481void 482hb_ot_layout_substitute_start (hb_buffer_t *buffer) 483{ 484 GSUB::substitute_start (buffer); 485} 486 487hb_bool_t 488hb_ot_layout_substitute_lookup (hb_face_t *face, 489 hb_buffer_t *buffer, 490 unsigned int lookup_index, 491 hb_mask_t mask) 492{ 493 hb_apply_context_t c (NULL, face, buffer, mask); 494 return _get_gsub (face).substitute_lookup (&c, lookup_index); 495} 496 497void 498hb_ot_layout_substitute_finish (hb_buffer_t *buffer HB_UNUSED) 499{ 500 GSUB::substitute_finish (buffer); 501} 502 503void 504hb_ot_layout_substitute_closure_lookup (hb_face_t *face, 505 hb_set_t *glyphs, 506 unsigned int lookup_index) 507{ 508 hb_closure_context_t c (face, glyphs); 509 _get_gsub (face).closure_lookup (&c, lookup_index); 510} 511 512/* 513 * GPOS 514 */ 515 516hb_bool_t 517hb_ot_layout_has_positioning (hb_face_t *face) 518{ 519 return &_get_gpos (face) != &Null(GPOS); 520} 521 522void 523hb_ot_layout_position_start (hb_buffer_t *buffer) 524{ 525 GPOS::position_start (buffer); 526} 527 528hb_bool_t 529hb_ot_layout_position_lookup (hb_font_t *font, 530 hb_buffer_t *buffer, 531 unsigned int lookup_index, 532 hb_mask_t mask) 533{ 534 hb_apply_context_t c (font, font->face, buffer, mask); 535 return _get_gpos (font->face).position_lookup (&c, lookup_index); 536} 537 538void 539hb_ot_layout_position_finish (hb_buffer_t *buffer) 540{ 541 GPOS::position_finish (buffer); 542} 543 544 545