1 /* 2 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 3 * 4 * This code is free software; you can redistribute it and/or modify it 5 * under the terms of the GNU General Public License version 2 only, as 6 * published by the Free Software Foundation. Oracle designates this 7 * particular file as subject to the "Classpath" exception as provided 8 * by Oracle in the LICENSE file that accompanied this code. 9 * 10 * This code is distributed in the hope that it will be useful, but WITHOUT 11 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 12 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 13 * version 2 for more details (a copy is included in the LICENSE file that 14 * accompanied this code). 15 * 16 * You should have received a copy of the GNU General Public License version 17 * 2 along with this work; if not, write to the Free Software Foundation, 18 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 19 * 20 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 21 * or visit www.oracle.com if you need additional information or have any 22 * questions. 23 */ 24 25 // This file is available under and governed by the GNU General Public 26 // License version 2 only, as published by the Free Software Foundation. 27 // However, the following notice accompanied the original version of this 28 // file: 29 // 30 /* 31 * Copyright © 2007,2008,2009 Red Hat, Inc. 32 * Copyright © 2012,2013 Google, Inc. 33 * 34 * This is part of HarfBuzz, a text shaping library. 35 * 36 * Permission is hereby granted, without written agreement and without 37 * license or royalty fees, to use, copy, modify, and distribute this 38 * software and its documentation for any purpose, provided that the 39 * above copyright notice and the following two paragraphs appear in 40 * all copies of this software. 41 * 42 * IN NO EVENT SHALL THE COPYRIGHT HOLDER BE LIABLE TO ANY PARTY FOR 43 * DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES 44 * ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN 45 * IF THE COPYRIGHT HOLDER HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH 46 * DAMAGE. 47 * 48 * THE COPYRIGHT HOLDER SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING, 49 * BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND 50 * FITNESS FOR A PARTICULAR PURPOSE. THE SOFTWARE PROVIDED HEREUNDER IS 51 * ON AN "AS IS" BASIS, AND THE COPYRIGHT HOLDER HAS NO OBLIGATION TO 52 * PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS. 53 * 54 * Red Hat Author(s): Behdad Esfahbod 55 * Google Author(s): Behdad Esfahbod 56 */ 57 58 #ifndef HB_OT_LAYOUT_PRIVATE_HH 59 #define HB_OT_LAYOUT_PRIVATE_HH 60 61 #include "hb-private.hh" 62 63 #include "hb-font-private.hh" 64 #include "hb-buffer-private.hh" 65 #include "hb-set-private.hh" 66 67 68 /* Private API corresponding to hb-ot-layout.h: */ 69 70 HB_INTERNAL hb_bool_t 71 hb_ot_layout_table_find_feature (hb_face_t *face, 72 hb_tag_t table_tag, 73 hb_tag_t feature_tag, 74 unsigned int *feature_index); 75 76 77 /* 78 * GDEF 79 */ 80 81 typedef enum 82 { 83 /* The following three match LookupFlags::Ignore* numbers. */ 84 HB_OT_LAYOUT_GLYPH_PROPS_BASE_GLYPH = 0x02u, 85 HB_OT_LAYOUT_GLYPH_PROPS_LIGATURE = 0x04u, 86 HB_OT_LAYOUT_GLYPH_PROPS_MARK = 0x08u, 87 88 /* The following are used internally; not derived from GDEF. */ 89 HB_OT_LAYOUT_GLYPH_PROPS_SUBSTITUTED = 0x10u, 90 HB_OT_LAYOUT_GLYPH_PROPS_LIGATED = 0x20u, 91 HB_OT_LAYOUT_GLYPH_PROPS_MULTIPLIED = 0x40u, 92 93 HB_OT_LAYOUT_GLYPH_PROPS_PRESERVE = HB_OT_LAYOUT_GLYPH_PROPS_SUBSTITUTED | 94 HB_OT_LAYOUT_GLYPH_PROPS_LIGATED | 95 HB_OT_LAYOUT_GLYPH_PROPS_MULTIPLIED 96 } hb_ot_layout_glyph_class_mask_t; 97 98 99 /* 100 * GSUB/GPOS 101 */ 102 103 HB_INTERNAL hb_bool_t 104 hb_ot_layout_lookup_would_substitute_fast (hb_face_t *face, 105 unsigned int lookup_index, 106 const hb_codepoint_t *glyphs, 107 unsigned int glyphs_length, 108 hb_bool_t zero_context); 109 110 111 /* Should be called before all the substitute_lookup's are done. */ 112 HB_INTERNAL void 113 hb_ot_layout_substitute_start (hb_font_t *font, 114 hb_buffer_t *buffer); 115 116 117 struct hb_ot_layout_lookup_accelerator_t; 118 119 namespace OT { 120 struct hb_apply_context_t; 121 struct SubstLookup; 122 } 123 124 HB_INTERNAL void 125 hb_ot_layout_substitute_lookup (OT::hb_apply_context_t *c, 126 const OT::SubstLookup &lookup, 127 const hb_ot_layout_lookup_accelerator_t &accel); 128 129 130 /* Should be called after all the substitute_lookup's are done */ 131 HB_INTERNAL void 132 hb_ot_layout_substitute_finish (hb_font_t *font, 133 hb_buffer_t *buffer); 134 135 136 /* Should be called before all the position_lookup's are done. Resets positions to zero. */ 137 HB_INTERNAL void 138 hb_ot_layout_position_start (hb_font_t *font, 139 hb_buffer_t *buffer); 140 141 /* Should be called after all the position_lookup's are done */ 142 HB_INTERNAL void 143 hb_ot_layout_position_finish (hb_font_t *font, 144 hb_buffer_t *buffer); 145 146 147 148 /* 149 * hb_ot_layout_t 150 */ 151 152 namespace OT { 153 struct GDEF; 154 struct GSUB; 155 struct GPOS; 156 } 157 158 struct hb_ot_layout_lookup_accelerator_t 159 { 160 template <typename TLookup> 161 inline void init (const TLookup &lookup) 162 { 163 digest.init (); 164 lookup.add_coverage (&digest); 165 } 166 167 inline void fini (void) 168 { 169 } 170 171 inline bool may_have (hb_codepoint_t g) const { 172 return digest.may_have (g); 173 } 174 175 private: 176 hb_set_digest_t digest; 177 }; 178 179 struct hb_ot_layout_t 180 { 181 hb_blob_t *gdef_blob; 182 hb_blob_t *gsub_blob; 183 hb_blob_t *gpos_blob; 184 185 const struct OT::GDEF *gdef; 186 const struct OT::GSUB *gsub; 187 const struct OT::GPOS *gpos; 188 189 unsigned int gsub_lookup_count; 190 unsigned int gpos_lookup_count; 191 192 hb_ot_layout_lookup_accelerator_t *gsub_accels; 193 hb_ot_layout_lookup_accelerator_t *gpos_accels; 194 }; 195 196 197 HB_INTERNAL hb_ot_layout_t * 198 _hb_ot_layout_create (hb_face_t *face); 199 200 HB_INTERNAL void 201 _hb_ot_layout_destroy (hb_ot_layout_t *layout); 202 203 204 #define hb_ot_layout_from_face(face) ((hb_ot_layout_t *) face->shaper_data.ot) 205 206 207 /* 208 * Buffer var routines. 209 */ 210 211 /* buffer var allocations, used during the entire shaping process */ 212 #define unicode_props0() var2.u8[0] 213 #define unicode_props1() var2.u8[1] 214 215 /* buffer var allocations, used during the GSUB/GPOS processing */ 216 #define glyph_props() var1.u16[0] /* GDEF glyph properties */ 217 #define lig_props() var1.u8[2] /* GSUB/GPOS ligature tracking */ 218 #define syllable() var1.u8[3] /* GSUB/GPOS shaping boundaries */ 219 220 221 /* loop over syllables */ 222 223 #define foreach_syllable(buffer, start, end) \ 224 for (unsigned int \ 225 _count = buffer->len, \ 226 start = 0, end = _count ? _next_syllable (buffer, 0) : 0; \ 227 start < _count; \ 228 start = end, end = _next_syllable (buffer, start)) 229 230 static inline unsigned int 231 _next_syllable (hb_buffer_t *buffer, unsigned int start) 232 { 233 hb_glyph_info_t *info = buffer->info; 234 unsigned int count = buffer->len; 235 236 unsigned int syllable = info[start].syllable(); 237 while (++start < count && syllable == info[start].syllable()) 238 ; 239 240 return start; 241 } 242 243 244 /* unicode_props */ 245 246 enum { 247 MASK0_ZWJ = 0x20u, 248 MASK0_ZWNJ = 0x40u, 249 MASK0_IGNORABLE = 0x80u, 250 MASK0_GEN_CAT = 0x1Fu 251 }; 252 253 static inline void 254 _hb_glyph_info_set_unicode_props (hb_glyph_info_t *info, hb_unicode_funcs_t *unicode) 255 { 256 /* XXX This shouldn't be inlined, or at least not while is_default_ignorable() is inline. */ 257 info->unicode_props0() = ((unsigned int) unicode->general_category (info->codepoint)) | 258 (unicode->is_default_ignorable (info->codepoint) ? MASK0_IGNORABLE : 0) | 259 (info->codepoint == 0x200Cu ? MASK0_ZWNJ : 0) | 260 (info->codepoint == 0x200Du ? MASK0_ZWJ : 0); 261 info->unicode_props1() = unicode->modified_combining_class (info->codepoint); 262 } 263 264 static inline void 265 _hb_glyph_info_set_general_category (hb_glyph_info_t *info, 266 hb_unicode_general_category_t gen_cat) 267 { 268 info->unicode_props0() = (unsigned int) gen_cat | ((info->unicode_props0()) & ~MASK0_GEN_CAT); 269 } 270 271 static inline hb_unicode_general_category_t 272 _hb_glyph_info_get_general_category (const hb_glyph_info_t *info) 273 { 274 return (hb_unicode_general_category_t) (info->unicode_props0() & MASK0_GEN_CAT); 275 } 276 277 static inline void 278 _hb_glyph_info_set_modified_combining_class (hb_glyph_info_t *info, 279 unsigned int modified_class) 280 { 281 info->unicode_props1() = modified_class; 282 } 283 284 static inline unsigned int 285 _hb_glyph_info_get_modified_combining_class (const hb_glyph_info_t *info) 286 { 287 return info->unicode_props1(); 288 } 289 290 static inline bool _hb_glyph_info_ligated (const hb_glyph_info_t *info); 291 292 static inline hb_bool_t 293 _hb_glyph_info_is_default_ignorable (const hb_glyph_info_t *info) 294 { 295 return (info->unicode_props0() & MASK0_IGNORABLE) && !_hb_glyph_info_ligated (info); 296 } 297 298 static inline hb_bool_t 299 _hb_glyph_info_is_zwnj (const hb_glyph_info_t *info) 300 { 301 return !!(info->unicode_props0() & MASK0_ZWNJ); 302 } 303 304 static inline hb_bool_t 305 _hb_glyph_info_is_zwj (const hb_glyph_info_t *info) 306 { 307 return !!(info->unicode_props0() & MASK0_ZWJ); 308 } 309 310 static inline void 311 _hb_glyph_info_flip_joiners (hb_glyph_info_t *info) 312 { 313 info->unicode_props0() ^= MASK0_ZWNJ | MASK0_ZWJ; 314 } 315 316 /* lig_props: aka lig_id / lig_comp 317 * 318 * When a ligature is formed: 319 * 320 * - The ligature glyph and any marks in between all the same newly allocated 321 * lig_id, 322 * - The ligature glyph will get lig_num_comps set to the number of components 323 * - The marks get lig_comp > 0, reflecting which component of the ligature 324 * they were applied to. 325 * - This is used in GPOS to attach marks to the right component of a ligature 326 * in MarkLigPos, 327 * - Note that when marks are ligated together, much of the above is skipped 328 * and the current lig_id reused. 329 * 330 * When a multiple-substitution is done: 331 * 332 * - All resulting glyphs will have lig_id = 0, 333 * - The resulting glyphs will have lig_comp = 0, 1, 2, ... respectively. 334 * - This is used in GPOS to attach marks to the first component of a 335 * multiple substitution in MarkBasePos. 336 * 337 * The numbers are also used in GPOS to do mark-to-mark positioning only 338 * to marks that belong to the same component of the same ligature. 339 */ 340 341 static inline void 342 _hb_glyph_info_clear_lig_props (hb_glyph_info_t *info) 343 { 344 info->lig_props() = 0; 345 } 346 347 #define IS_LIG_BASE 0x10 348 349 static inline void 350 _hb_glyph_info_set_lig_props_for_ligature (hb_glyph_info_t *info, 351 unsigned int lig_id, 352 unsigned int lig_num_comps) 353 { 354 info->lig_props() = (lig_id << 5) | IS_LIG_BASE | (lig_num_comps & 0x0F); 355 } 356 357 static inline void 358 _hb_glyph_info_set_lig_props_for_mark (hb_glyph_info_t *info, 359 unsigned int lig_id, 360 unsigned int lig_comp) 361 { 362 info->lig_props() = (lig_id << 5) | (lig_comp & 0x0F); 363 } 364 365 static inline void 366 _hb_glyph_info_set_lig_props_for_component (hb_glyph_info_t *info, unsigned int comp) 367 { 368 _hb_glyph_info_set_lig_props_for_mark (info, 0, comp); 369 } 370 371 static inline unsigned int 372 _hb_glyph_info_get_lig_id (const hb_glyph_info_t *info) 373 { 374 return info->lig_props() >> 5; 375 } 376 377 static inline bool 378 _hb_glyph_info_ligated_internal (const hb_glyph_info_t *info) 379 { 380 return !!(info->lig_props() & IS_LIG_BASE); 381 } 382 383 static inline unsigned int 384 _hb_glyph_info_get_lig_comp (const hb_glyph_info_t *info) 385 { 386 if (_hb_glyph_info_ligated_internal (info)) 387 return 0; 388 else 389 return info->lig_props() & 0x0F; 390 } 391 392 static inline unsigned int 393 _hb_glyph_info_get_lig_num_comps (const hb_glyph_info_t *info) 394 { 395 if ((info->glyph_props() & HB_OT_LAYOUT_GLYPH_PROPS_LIGATURE) && 396 _hb_glyph_info_ligated_internal (info)) 397 return info->lig_props() & 0x0F; 398 else 399 return 1; 400 } 401 402 static inline uint8_t 403 _hb_allocate_lig_id (hb_buffer_t *buffer) { 404 uint8_t lig_id = buffer->next_serial () & 0x07; 405 if (unlikely (!lig_id)) 406 lig_id = _hb_allocate_lig_id (buffer); /* in case of overflow */ 407 return lig_id; 408 } 409 410 /* glyph_props: */ 411 412 static inline void 413 _hb_glyph_info_set_glyph_props (hb_glyph_info_t *info, unsigned int props) 414 { 415 info->glyph_props() = props; 416 } 417 418 static inline unsigned int 419 _hb_glyph_info_get_glyph_props (const hb_glyph_info_t *info) 420 { 421 return info->glyph_props(); 422 } 423 424 static inline bool 425 _hb_glyph_info_is_base_glyph (const hb_glyph_info_t *info) 426 { 427 return !!(info->glyph_props() & HB_OT_LAYOUT_GLYPH_PROPS_BASE_GLYPH); 428 } 429 430 static inline bool 431 _hb_glyph_info_is_ligature (const hb_glyph_info_t *info) 432 { 433 return !!(info->glyph_props() & HB_OT_LAYOUT_GLYPH_PROPS_LIGATURE); 434 } 435 436 static inline bool 437 _hb_glyph_info_is_mark (const hb_glyph_info_t *info) 438 { 439 return !!(info->glyph_props() & HB_OT_LAYOUT_GLYPH_PROPS_MARK); 440 } 441 442 static inline bool 443 _hb_glyph_info_substituted (const hb_glyph_info_t *info) 444 { 445 return !!(info->glyph_props() & HB_OT_LAYOUT_GLYPH_PROPS_SUBSTITUTED); 446 } 447 448 static inline bool 449 _hb_glyph_info_ligated (const hb_glyph_info_t *info) 450 { 451 return !!(info->glyph_props() & HB_OT_LAYOUT_GLYPH_PROPS_LIGATED); 452 } 453 454 static inline bool 455 _hb_glyph_info_multiplied (const hb_glyph_info_t *info) 456 { 457 return !!(info->glyph_props() & HB_OT_LAYOUT_GLYPH_PROPS_MULTIPLIED); 458 } 459 460 static inline bool 461 _hb_glyph_info_ligated_and_didnt_multiply (const hb_glyph_info_t *info) 462 { 463 return _hb_glyph_info_ligated (info) && !_hb_glyph_info_multiplied (info); 464 } 465 466 static inline void 467 _hb_glyph_info_clear_ligated_and_multiplied (hb_glyph_info_t *info) 468 { 469 info->glyph_props() &= ~(HB_OT_LAYOUT_GLYPH_PROPS_LIGATED | 470 HB_OT_LAYOUT_GLYPH_PROPS_MULTIPLIED); 471 } 472 473 static inline void 474 _hb_glyph_info_clear_substituted_and_ligated_and_multiplied (hb_glyph_info_t *info) 475 { 476 info->glyph_props() &= ~(HB_OT_LAYOUT_GLYPH_PROPS_SUBSTITUTED | 477 HB_OT_LAYOUT_GLYPH_PROPS_LIGATED | 478 HB_OT_LAYOUT_GLYPH_PROPS_MULTIPLIED); 479 } 480 481 482 /* Allocation / deallocation. */ 483 484 static inline void 485 _hb_buffer_allocate_unicode_vars (hb_buffer_t *buffer) 486 { 487 HB_BUFFER_ALLOCATE_VAR (buffer, unicode_props0); 488 HB_BUFFER_ALLOCATE_VAR (buffer, unicode_props1); 489 } 490 491 static inline void 492 _hb_buffer_deallocate_unicode_vars (hb_buffer_t *buffer) 493 { 494 HB_BUFFER_DEALLOCATE_VAR (buffer, unicode_props0); 495 HB_BUFFER_DEALLOCATE_VAR (buffer, unicode_props1); 496 } 497 498 static inline void 499 _hb_buffer_assert_unicode_vars (hb_buffer_t *buffer) 500 { 501 HB_BUFFER_ASSERT_VAR (buffer, unicode_props0); 502 HB_BUFFER_ASSERT_VAR (buffer, unicode_props1); 503 } 504 505 static inline void 506 _hb_buffer_allocate_gsubgpos_vars (hb_buffer_t *buffer) 507 { 508 HB_BUFFER_ALLOCATE_VAR (buffer, glyph_props); 509 HB_BUFFER_ALLOCATE_VAR (buffer, lig_props); 510 HB_BUFFER_ALLOCATE_VAR (buffer, syllable); 511 } 512 513 static inline void 514 _hb_buffer_deallocate_gsubgpos_vars (hb_buffer_t *buffer) 515 { 516 HB_BUFFER_DEALLOCATE_VAR (buffer, syllable); 517 HB_BUFFER_DEALLOCATE_VAR (buffer, lig_props); 518 HB_BUFFER_DEALLOCATE_VAR (buffer, glyph_props); 519 } 520 521 static inline void 522 _hb_buffer_assert_gsubgpos_vars (hb_buffer_t *buffer) 523 { 524 HB_BUFFER_ASSERT_VAR (buffer, glyph_props); 525 HB_BUFFER_ASSERT_VAR (buffer, lig_props); 526 HB_BUFFER_ASSERT_VAR (buffer, syllable); 527 } 528 529 /* Make sure no one directly touches our props... */ 530 #undef unicode_props0 531 #undef unicode_props1 532 #undef lig_props 533 #undef glyph_props 534 535 536 #endif /* HB_OT_LAYOUT_PRIVATE_HH */