hb-ot-layout.cc revision e72b360ac6381b549249b8836fa3e70b909d3437
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 41 42hb_ot_layout_t * 43_hb_ot_layout_create (hb_face_t *face) 44{ 45 /* TODO Remove this object altogether */ 46 hb_ot_layout_t *layout = (hb_ot_layout_t *) calloc (1, sizeof (hb_ot_layout_t)); 47 48 layout->gdef_blob = Sanitizer<GDEF>::sanitize (hb_face_reference_table (face, HB_OT_TAG_GDEF)); 49 layout->gdef = Sanitizer<GDEF>::lock_instance (layout->gdef_blob); 50 51 layout->gsub_blob = Sanitizer<GSUB>::sanitize (hb_face_reference_table (face, HB_OT_TAG_GSUB)); 52 layout->gsub = Sanitizer<GSUB>::lock_instance (layout->gsub_blob); 53 54 layout->gpos_blob = Sanitizer<GPOS>::sanitize (hb_face_reference_table (face, HB_OT_TAG_GPOS)); 55 layout->gpos = Sanitizer<GPOS>::lock_instance (layout->gpos_blob); 56 57 return layout; 58} 59 60void 61_hb_ot_layout_destroy (hb_ot_layout_t *layout) 62{ 63 hb_blob_destroy (layout->gdef_blob); 64 hb_blob_destroy (layout->gsub_blob); 65 hb_blob_destroy (layout->gpos_blob); 66 67 free (layout); 68} 69 70static inline const GDEF& 71_get_gdef (hb_face_t *face) 72{ 73 return likely (face->ot_layout && face->ot_layout->gdef) ? *face->ot_layout->gdef : Null(GDEF); 74} 75static inline const GSUB& 76_get_gsub (hb_face_t *face) 77{ 78 return likely (face->ot_layout && face->ot_layout->gsub) ? *face->ot_layout->gsub : Null(GSUB); 79} 80static inline const GPOS& 81_get_gpos (hb_face_t *face) 82{ 83 return likely (face->ot_layout && face->ot_layout->gpos) ? *face->ot_layout->gpos : Null(GPOS); 84} 85 86 87/* 88 * GDEF 89 */ 90 91hb_bool_t 92hb_ot_layout_has_glyph_classes (hb_face_t *face) 93{ 94 return _get_gdef (face).has_glyph_classes (); 95} 96 97static inline unsigned int 98_hb_ot_layout_get_glyph_property (hb_face_t *face, 99 hb_glyph_info_t *info) 100{ 101 if (!info->props_cache()) 102 { 103 const GDEF &gdef = _get_gdef (face); 104 info->props_cache() = gdef.get_glyph_props (info->codepoint); 105 } 106 107 return info->props_cache(); 108} 109 110static inline hb_bool_t 111_hb_ot_layout_match_properties_mark (hb_face_t *face, 112 hb_codepoint_t glyph, 113 unsigned int glyph_props, 114 unsigned int lookup_props) 115{ 116 /* If using mark filtering sets, the high short of 117 * lookup_props has the set index. 118 */ 119 if (lookup_props & LookupFlag::UseMarkFilteringSet) 120 return _get_gdef (face).mark_set_covers (lookup_props >> 16, glyph); 121 122 /* The second byte of lookup_props has the meaning 123 * "ignore marks of attachment type different than 124 * the attachment type specified." 125 */ 126 if (lookup_props & LookupFlag::MarkAttachmentType) 127 return (lookup_props & LookupFlag::MarkAttachmentType) == (glyph_props & LookupFlag::MarkAttachmentType); 128 129 return true; 130} 131 132static inline hb_bool_t 133_hb_ot_layout_match_properties (hb_face_t *face, 134 hb_codepoint_t glyph, 135 unsigned int glyph_props, 136 unsigned int lookup_props) 137{ 138 /* Not covered, if, for example, glyph class is ligature and 139 * lookup_props includes LookupFlags::IgnoreLigatures 140 */ 141 if (glyph_props & lookup_props & LookupFlag::IgnoreFlags) 142 return false; 143 144 if (unlikely (glyph_props & HB_OT_LAYOUT_GLYPH_CLASS_MARK)) 145 return _hb_ot_layout_match_properties_mark (face, glyph, glyph_props, lookup_props); 146 147 return true; 148} 149 150hb_bool_t 151_hb_ot_layout_check_glyph_property (hb_face_t *face, 152 hb_glyph_info_t *ginfo, 153 unsigned int lookup_props, 154 unsigned int *property_out) 155{ 156 unsigned int property; 157 158 property = _hb_ot_layout_get_glyph_property (face, ginfo); 159 *property_out = property; 160 161 return _hb_ot_layout_match_properties (face, ginfo->codepoint, property, lookup_props); 162} 163 164hb_bool_t 165_hb_ot_layout_skip_mark (hb_face_t *face, 166 hb_glyph_info_t *ginfo, 167 unsigned int lookup_props, 168 unsigned int *property_out) 169{ 170 unsigned int property; 171 172 property = _hb_ot_layout_get_glyph_property (face, ginfo); 173 if (property_out) 174 *property_out = property; 175 176 /* If it's a mark, skip it if we don't accept it. */ 177 if (unlikely (property & HB_OT_LAYOUT_GLYPH_CLASS_MARK)) 178 return !_hb_ot_layout_match_properties (face, ginfo->codepoint, property, lookup_props); 179 180 /* If not a mark, don't skip. */ 181 return false; 182} 183 184 185 186unsigned int 187hb_ot_layout_get_attach_points (hb_face_t *face, 188 hb_codepoint_t glyph, 189 unsigned int start_offset, 190 unsigned int *point_count /* IN/OUT */, 191 unsigned int *point_array /* OUT */) 192{ 193 return _get_gdef (face).get_attach_points (glyph, start_offset, point_count, point_array); 194} 195 196unsigned int 197hb_ot_layout_get_ligature_carets (hb_font_t *font, 198 hb_direction_t direction, 199 hb_codepoint_t glyph, 200 unsigned int start_offset, 201 unsigned int *caret_count /* IN/OUT */, 202 int *caret_array /* OUT */) 203{ 204 return _get_gdef (font->face).get_lig_carets (font, direction, glyph, start_offset, caret_count, caret_array); 205} 206 207/* 208 * GSUB/GPOS 209 */ 210 211static const GSUBGPOS& 212get_gsubgpos_table (hb_face_t *face, 213 hb_tag_t table_tag) 214{ 215 switch (table_tag) { 216 case HB_OT_TAG_GSUB: return _get_gsub (face); 217 case HB_OT_TAG_GPOS: return _get_gpos (face); 218 default: return Null(GSUBGPOS); 219 } 220} 221 222 223unsigned int 224hb_ot_layout_table_get_script_tags (hb_face_t *face, 225 hb_tag_t table_tag, 226 unsigned int start_offset, 227 unsigned int *script_count /* IN/OUT */, 228 hb_tag_t *script_tags /* OUT */) 229{ 230 const GSUBGPOS &g = get_gsubgpos_table (face, table_tag); 231 232 return g.get_script_tags (start_offset, script_count, script_tags); 233} 234 235hb_bool_t 236hb_ot_layout_table_find_script (hb_face_t *face, 237 hb_tag_t table_tag, 238 hb_tag_t script_tag, 239 unsigned int *script_index) 240{ 241 ASSERT_STATIC (Index::NOT_FOUND_INDEX == HB_OT_LAYOUT_NO_SCRIPT_INDEX); 242 const GSUBGPOS &g = get_gsubgpos_table (face, table_tag); 243 244 if (g.find_script_index (script_tag, script_index)) 245 return true; 246 247 /* try finding 'DFLT' */ 248 if (g.find_script_index (HB_OT_TAG_DEFAULT_SCRIPT, script_index)) 249 return false; 250 251 /* try with 'dflt'; MS site has had typos and many fonts use it now :(. 252 * including many versions of DejaVu Sans Mono! */ 253 if (g.find_script_index (HB_OT_TAG_DEFAULT_LANGUAGE, script_index)) 254 return false; 255 256 if (script_index) *script_index = HB_OT_LAYOUT_NO_SCRIPT_INDEX; 257 return false; 258} 259 260hb_bool_t 261hb_ot_layout_table_choose_script (hb_face_t *face, 262 hb_tag_t table_tag, 263 const hb_tag_t *script_tags, 264 unsigned int *script_index, 265 hb_tag_t *chosen_script) 266{ 267 ASSERT_STATIC (Index::NOT_FOUND_INDEX == HB_OT_LAYOUT_NO_SCRIPT_INDEX); 268 const GSUBGPOS &g = get_gsubgpos_table (face, table_tag); 269 270 while (*script_tags) 271 { 272 if (g.find_script_index (*script_tags, script_index)) { 273 if (chosen_script) 274 *chosen_script = *script_tags; 275 return true; 276 } 277 script_tags++; 278 } 279 280 /* try finding 'DFLT' */ 281 if (g.find_script_index (HB_OT_TAG_DEFAULT_SCRIPT, script_index)) { 282 if (chosen_script) 283 *chosen_script = HB_OT_TAG_DEFAULT_SCRIPT; 284 return false; 285 } 286 287 /* try with 'dflt'; MS site has had typos and many fonts use it now :( */ 288 if (g.find_script_index (HB_OT_TAG_DEFAULT_LANGUAGE, script_index)) { 289 if (chosen_script) 290 *chosen_script = HB_OT_TAG_DEFAULT_LANGUAGE; 291 return false; 292 } 293 294 /* try with 'latn'; some old fonts put their features there even though 295 they're really trying to support Thai, for example :( */ 296#define HB_OT_TAG_LATIN_SCRIPT HB_TAG ('l', 'a', 't', 'n') 297 if (g.find_script_index (HB_OT_TAG_LATIN_SCRIPT, script_index)) { 298 if (chosen_script) 299 *chosen_script = HB_OT_TAG_LATIN_SCRIPT; 300 return false; 301 } 302 303 if (script_index) *script_index = HB_OT_LAYOUT_NO_SCRIPT_INDEX; 304 if (chosen_script) 305 *chosen_script = HB_OT_LAYOUT_NO_SCRIPT_INDEX; 306 return false; 307} 308 309unsigned int 310hb_ot_layout_table_get_feature_tags (hb_face_t *face, 311 hb_tag_t table_tag, 312 unsigned int start_offset, 313 unsigned int *feature_count /* IN/OUT */, 314 hb_tag_t *feature_tags /* OUT */) 315{ 316 const GSUBGPOS &g = get_gsubgpos_table (face, table_tag); 317 318 return g.get_feature_tags (start_offset, feature_count, feature_tags); 319} 320 321 322unsigned int 323hb_ot_layout_script_get_language_tags (hb_face_t *face, 324 hb_tag_t table_tag, 325 unsigned int script_index, 326 unsigned int start_offset, 327 unsigned int *language_count /* IN/OUT */, 328 hb_tag_t *language_tags /* OUT */) 329{ 330 const Script &s = get_gsubgpos_table (face, table_tag).get_script (script_index); 331 332 return s.get_lang_sys_tags (start_offset, language_count, language_tags); 333} 334 335hb_bool_t 336hb_ot_layout_script_find_language (hb_face_t *face, 337 hb_tag_t table_tag, 338 unsigned int script_index, 339 hb_tag_t language_tag, 340 unsigned int *language_index) 341{ 342 ASSERT_STATIC (Index::NOT_FOUND_INDEX == HB_OT_LAYOUT_DEFAULT_LANGUAGE_INDEX); 343 const Script &s = get_gsubgpos_table (face, table_tag).get_script (script_index); 344 345 if (s.find_lang_sys_index (language_tag, language_index)) 346 return true; 347 348 /* try with 'dflt'; MS site has had typos and many fonts use it now :( */ 349 if (s.find_lang_sys_index (HB_OT_TAG_DEFAULT_LANGUAGE, language_index)) 350 return false; 351 352 if (language_index) *language_index = HB_OT_LAYOUT_DEFAULT_LANGUAGE_INDEX; 353 return false; 354} 355 356hb_bool_t 357hb_ot_layout_language_get_required_feature_index (hb_face_t *face, 358 hb_tag_t table_tag, 359 unsigned int script_index, 360 unsigned int language_index, 361 unsigned int *feature_index) 362{ 363 const LangSys &l = get_gsubgpos_table (face, table_tag).get_script (script_index).get_lang_sys (language_index); 364 365 if (feature_index) *feature_index = l.get_required_feature_index (); 366 367 return l.has_required_feature (); 368} 369 370unsigned int 371hb_ot_layout_language_get_feature_indexes (hb_face_t *face, 372 hb_tag_t table_tag, 373 unsigned int script_index, 374 unsigned int language_index, 375 unsigned int start_offset, 376 unsigned int *feature_count /* IN/OUT */, 377 unsigned int *feature_indexes /* OUT */) 378{ 379 const GSUBGPOS &g = get_gsubgpos_table (face, table_tag); 380 const LangSys &l = g.get_script (script_index).get_lang_sys (language_index); 381 382 return l.get_feature_indexes (start_offset, feature_count, feature_indexes); 383} 384 385unsigned int 386hb_ot_layout_language_get_feature_tags (hb_face_t *face, 387 hb_tag_t table_tag, 388 unsigned int script_index, 389 unsigned int language_index, 390 unsigned int start_offset, 391 unsigned int *feature_count /* IN/OUT */, 392 hb_tag_t *feature_tags /* OUT */) 393{ 394 const GSUBGPOS &g = get_gsubgpos_table (face, table_tag); 395 const LangSys &l = g.get_script (script_index).get_lang_sys (language_index); 396 397 ASSERT_STATIC (sizeof (unsigned int) == sizeof (hb_tag_t)); 398 unsigned int ret = l.get_feature_indexes (start_offset, feature_count, (unsigned int *) feature_tags); 399 400 if (feature_tags) { 401 unsigned int count = *feature_count; 402 for (unsigned int i = 0; i < count; i++) 403 feature_tags[i] = g.get_feature_tag ((unsigned int) feature_tags[i]); 404 } 405 406 return ret; 407} 408 409 410hb_bool_t 411hb_ot_layout_language_find_feature (hb_face_t *face, 412 hb_tag_t table_tag, 413 unsigned int script_index, 414 unsigned int language_index, 415 hb_tag_t feature_tag, 416 unsigned int *feature_index) 417{ 418 ASSERT_STATIC (Index::NOT_FOUND_INDEX == HB_OT_LAYOUT_NO_FEATURE_INDEX); 419 const GSUBGPOS &g = get_gsubgpos_table (face, table_tag); 420 const LangSys &l = g.get_script (script_index).get_lang_sys (language_index); 421 422 unsigned int num_features = l.get_feature_count (); 423 for (unsigned int i = 0; i < num_features; i++) { 424 unsigned int f_index = l.get_feature_index (i); 425 426 if (feature_tag == g.get_feature_tag (f_index)) { 427 if (feature_index) *feature_index = f_index; 428 return true; 429 } 430 } 431 432 if (feature_index) *feature_index = HB_OT_LAYOUT_NO_FEATURE_INDEX; 433 return false; 434} 435 436unsigned int 437hb_ot_layout_feature_get_lookup_indexes (hb_face_t *face, 438 hb_tag_t table_tag, 439 unsigned int feature_index, 440 unsigned int start_offset, 441 unsigned int *lookup_count /* IN/OUT */, 442 unsigned int *lookup_indexes /* OUT */) 443{ 444 const GSUBGPOS &g = get_gsubgpos_table (face, table_tag); 445 const Feature &f = g.get_feature (feature_index); 446 447 return f.get_lookup_indexes (start_offset, lookup_count, lookup_indexes); 448} 449 450 451/* 452 * GSUB 453 */ 454 455hb_bool_t 456hb_ot_layout_has_substitution (hb_face_t *face) 457{ 458 return &_get_gsub (face) != &Null(GSUB); 459} 460 461hb_bool_t 462hb_ot_layout_would_substitute_lookup (hb_face_t *face, 463 const hb_codepoint_t *glyphs, 464 unsigned int glyphs_length, 465 unsigned int lookup_index) 466{ 467 if (unlikely (glyphs_length < 1 || glyphs_length > 2)) return false; 468 hb_would_apply_context_t c (face, glyphs[0], glyphs_length == 2 ? glyphs[1] : -1); 469 return _get_gsub (face).would_substitute_lookup (&c, lookup_index); 470} 471 472void 473hb_ot_layout_substitute_start (hb_buffer_t *buffer) 474{ 475 GSUB::substitute_start (buffer); 476} 477 478hb_bool_t 479hb_ot_layout_substitute_lookup (hb_face_t *face, 480 hb_buffer_t *buffer, 481 unsigned int lookup_index, 482 hb_mask_t mask) 483{ 484 hb_apply_context_t c (NULL, face, buffer, mask); 485 return _get_gsub (face).substitute_lookup (&c, lookup_index); 486} 487 488void 489hb_ot_layout_substitute_finish (hb_buffer_t *buffer HB_UNUSED) 490{ 491 GSUB::substitute_finish (buffer); 492} 493 494void 495hb_ot_layout_substitute_closure_lookup (hb_face_t *face, 496 hb_set_t *glyphs, 497 unsigned int lookup_index) 498{ 499 hb_closure_context_t c (face, glyphs); 500 _get_gsub (face).closure_lookup (&c, lookup_index); 501} 502 503/* 504 * GPOS 505 */ 506 507hb_bool_t 508hb_ot_layout_has_positioning (hb_face_t *face) 509{ 510 return &_get_gpos (face) != &Null(GPOS); 511} 512 513void 514hb_ot_layout_position_start (hb_buffer_t *buffer) 515{ 516 GPOS::position_start (buffer); 517} 518 519hb_bool_t 520hb_ot_layout_position_lookup (hb_font_t *font, 521 hb_buffer_t *buffer, 522 unsigned int lookup_index, 523 hb_mask_t mask) 524{ 525 hb_apply_context_t c (font, font->face, buffer, mask); 526 return _get_gpos (font->face).position_lookup (&c, lookup_index); 527} 528 529void 530hb_ot_layout_position_finish (hb_buffer_t *buffer) 531{ 532 GPOS::position_finish (buffer); 533} 534 535 536