1 /* 2 * Copyright © 2016 Elie Roux <elie.roux@telecom-bretagne.eu> 3 * Copyright © 2018 Google, Inc. 4 * Copyright © 2018 Ebrahim Byagowi 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 * Google Author(s): Behdad Esfahbod 27 */ 28 29 #ifndef HB_OT_LAYOUT_BASE_TABLE_HH 30 #define HB_OT_LAYOUT_BASE_TABLE_HH 31 32 #include "hb-open-type.hh" 33 #include "hb-ot-layout-common.hh" 34 35 /* To be removed */ 36 typedef hb_tag_t hb_ot_layout_baseline_t; 37 38 namespace OT { 39 40 /* 41 * BASE -- Baseline 42 * https://docs.microsoft.com/en-us/typography/opentype/spec/base 43 */ 44 45 struct BaseCoordFormat1 46 { get_coordOT::BaseCoordFormat147 hb_position_t get_coord () const { return coordinate; } 48 sanitizeOT::BaseCoordFormat149 bool sanitize (hb_sanitize_context_t *c) const 50 { 51 TRACE_SANITIZE (this); 52 return_trace (likely (c->check_struct (this))); 53 } 54 55 protected: 56 HBUINT16 format; /* Format identifier--format = 1 */ 57 FWORD coordinate; /* X or Y value, in design units */ 58 public: 59 DEFINE_SIZE_STATIC (4); 60 }; 61 62 struct BaseCoordFormat2 63 { get_coordOT::BaseCoordFormat264 hb_position_t get_coord () const 65 { 66 /* TODO */ 67 return coordinate; 68 } 69 sanitizeOT::BaseCoordFormat270 bool sanitize (hb_sanitize_context_t *c) const 71 { 72 TRACE_SANITIZE (this); 73 return_trace (c->check_struct (this)); 74 } 75 76 protected: 77 HBUINT16 format; /* Format identifier--format = 2 */ 78 FWORD coordinate; /* X or Y value, in design units */ 79 GlyphID referenceGlyph; /* Glyph ID of control glyph */ 80 HBUINT16 coordPoint; /* Index of contour point on the 81 * reference glyph */ 82 public: 83 DEFINE_SIZE_STATIC (8); 84 }; 85 86 struct BaseCoordFormat3 87 { get_coordOT::BaseCoordFormat388 hb_position_t get_coord (hb_font_t *font, 89 const VariationStore &var_store, 90 hb_direction_t direction) const 91 { 92 const Device &device = this+deviceTable; 93 return coordinate + (HB_DIRECTION_IS_VERTICAL (direction) ? 94 device.get_y_delta (font, var_store) : 95 device.get_x_delta (font, var_store)); 96 } 97 98 sanitizeOT::BaseCoordFormat399 bool sanitize (hb_sanitize_context_t *c) const 100 { 101 TRACE_SANITIZE (this); 102 return_trace (likely (c->check_struct (this) && 103 deviceTable.sanitize (c, this))); 104 } 105 106 protected: 107 HBUINT16 format; /* Format identifier--format = 3 */ 108 FWORD coordinate; /* X or Y value, in design units */ 109 OffsetTo<Device> 110 deviceTable; /* Offset to Device table for X or 111 * Y value, from beginning of 112 * BaseCoord table (may be NULL). */ 113 public: 114 DEFINE_SIZE_STATIC (6); 115 }; 116 117 struct BaseCoord 118 { get_coordOT::BaseCoord119 hb_position_t get_coord (hb_font_t *font, 120 const VariationStore &var_store, 121 hb_direction_t direction) const 122 { 123 switch (u.format) { 124 case 1: return u.format1.get_coord (); 125 case 2: return u.format2.get_coord (); 126 case 3: return u.format3.get_coord (font, var_store, direction); 127 default:return 0; 128 } 129 } 130 sanitizeOT::BaseCoord131 bool sanitize (hb_sanitize_context_t *c) const 132 { 133 TRACE_SANITIZE (this); 134 if (unlikely (!u.format.sanitize (c))) return_trace (false); 135 switch (u.format) { 136 case 1: return_trace (u.format1.sanitize (c)); 137 case 2: return_trace (u.format2.sanitize (c)); 138 case 3: return_trace (u.format3.sanitize (c)); 139 default:return_trace (false); 140 } 141 } 142 143 protected: 144 union { 145 HBUINT16 format; 146 BaseCoordFormat1 format1; 147 BaseCoordFormat2 format2; 148 BaseCoordFormat3 format3; 149 } u; 150 public: 151 DEFINE_SIZE_UNION (2, format); 152 }; 153 154 struct FeatMinMaxRecord 155 { cmpOT::FeatMinMaxRecord156 static int cmp (const void *key_, const void *entry_) 157 { 158 hb_tag_t key = * (hb_tag_t *) key_; 159 const FeatMinMaxRecord &entry = * (const FeatMinMaxRecord *) entry_; 160 return key < (unsigned int) entry.tag ? -1 : 161 key > (unsigned int) entry.tag ? 1 : 162 0; 163 } 164 get_min_maxOT::FeatMinMaxRecord165 void get_min_max (const BaseCoord **min, const BaseCoord **max) const 166 { 167 if (likely (min)) *min = &(this+minCoord); 168 if (likely (max)) *max = &(this+maxCoord); 169 } 170 sanitizeOT::FeatMinMaxRecord171 bool sanitize (hb_sanitize_context_t *c, const void *base) const 172 { 173 TRACE_SANITIZE (this); 174 return_trace (likely (c->check_struct (this) && 175 minCoord.sanitize (c, this) && 176 maxCoord.sanitize (c, this))); 177 } 178 179 protected: 180 Tag tag; /* 4-byte feature identification tag--must 181 * match feature tag in FeatureList */ 182 OffsetTo<BaseCoord> 183 minCoord; /* Offset to BaseCoord table that defines 184 * the minimum extent value, from beginning 185 * of MinMax table (may be NULL) */ 186 OffsetTo<BaseCoord> 187 maxCoord; /* Offset to BaseCoord table that defines 188 * the maximum extent value, from beginning 189 * of MinMax table (may be NULL) */ 190 public: 191 DEFINE_SIZE_STATIC (8); 192 193 }; 194 195 struct MinMax 196 { get_min_maxOT::MinMax197 void get_min_max (hb_tag_t feature_tag, 198 const BaseCoord **min, 199 const BaseCoord **max) const 200 { 201 /* TODO Replace hb_bsearch() with .bsearch(). */ 202 const FeatMinMaxRecord *minMaxCoord = (const FeatMinMaxRecord *) 203 hb_bsearch (&feature_tag, featMinMaxRecords.arrayZ, 204 featMinMaxRecords.len, 205 FeatMinMaxRecord::static_size, 206 FeatMinMaxRecord::cmp); 207 if (minMaxCoord) 208 minMaxCoord->get_min_max (min, max); 209 else 210 { 211 if (likely (min)) *min = &(this+minCoord); 212 if (likely (max)) *max = &(this+maxCoord); 213 } 214 } 215 sanitizeOT::MinMax216 bool sanitize (hb_sanitize_context_t *c) const 217 { 218 TRACE_SANITIZE (this); 219 return_trace (likely (c->check_struct (this) && 220 minCoord.sanitize (c, this) && 221 maxCoord.sanitize (c, this) && 222 featMinMaxRecords.sanitize (c, this))); 223 } 224 225 protected: 226 OffsetTo<BaseCoord> 227 minCoord; /* Offset to BaseCoord table that defines 228 * minimum extent value, from the beginning 229 * of MinMax table (may be NULL) */ 230 OffsetTo<BaseCoord> 231 maxCoord; /* Offset to BaseCoord table that defines 232 * maximum extent value, from the beginning 233 * of MinMax table (may be NULL) */ 234 SortedArrayOf<FeatMinMaxRecord> 235 featMinMaxRecords; 236 /* Array of FeatMinMaxRecords, in alphabetical 237 * order by featureTableTag */ 238 public: 239 DEFINE_SIZE_ARRAY (6, featMinMaxRecords); 240 }; 241 242 struct BaseValues 243 { get_base_coordOT::BaseValues244 const BaseCoord &get_base_coord (int baseline_tag_index) const 245 { 246 if (baseline_tag_index == -1) baseline_tag_index = defaultIndex; 247 return this+baseCoords[baseline_tag_index]; 248 } 249 sanitizeOT::BaseValues250 bool sanitize (hb_sanitize_context_t *c) const 251 { 252 TRACE_SANITIZE (this); 253 return_trace (likely (c->check_struct (this) && 254 baseCoords.sanitize (c, this))); 255 } 256 257 protected: 258 Index defaultIndex; /* Index number of default baseline for this 259 * script — equals index position of baseline tag 260 * in baselineTags array of the BaseTagList */ 261 OffsetArrayOf<BaseCoord> 262 baseCoords; /* Number of BaseCoord tables defined — should equal 263 * baseTagCount in the BaseTagList 264 * 265 * Array of offsets to BaseCoord tables, from beginning of 266 * BaseValues table — order matches baselineTags array in 267 * the BaseTagList */ 268 public: 269 DEFINE_SIZE_ARRAY (4, baseCoords); 270 }; 271 272 struct BaseLangSysRecord 273 { cmpOT::BaseLangSysRecord274 static int cmp (const void *key_, const void *entry_) 275 { 276 hb_tag_t key = * (hb_tag_t *) key_; 277 const BaseLangSysRecord &entry = * (const BaseLangSysRecord *) entry_; 278 return key < (unsigned int) entry.baseLangSysTag ? -1 : 279 key > (unsigned int) entry.baseLangSysTag ? 1 : 280 0; 281 } 282 get_min_maxOT::BaseLangSysRecord283 const MinMax &get_min_max () const 284 { return this+minMax; } 285 sanitizeOT::BaseLangSysRecord286 bool sanitize (hb_sanitize_context_t *c, const void *base) const 287 { 288 TRACE_SANITIZE (this); 289 return_trace (likely (c->check_struct (this) && 290 minMax.sanitize (c, this))); 291 } 292 293 protected: 294 Tag baseLangSysTag; /* 4-byte language system identification tag */ 295 OffsetTo<MinMax> 296 minMax; /* Offset to MinMax table, from beginning 297 * of BaseScript table */ 298 public: 299 DEFINE_SIZE_STATIC (6); 300 }; 301 302 struct BaseScript 303 { get_min_maxOT::BaseScript304 const MinMax &get_min_max (hb_tag_t language_tag) const 305 { 306 /* TODO Replace hb_bsearch() with .bsearch(). */ 307 const BaseLangSysRecord* record = (const BaseLangSysRecord *) 308 hb_bsearch (&language_tag, baseLangSysRecords.arrayZ, 309 baseLangSysRecords.len, 310 BaseLangSysRecord::static_size, 311 BaseLangSysRecord::cmp); 312 return record ? record->get_min_max () : this+defaultMinMax; 313 } 314 get_base_coordOT::BaseScript315 const BaseCoord &get_base_coord (int baseline_tag_index) const 316 { return (this+baseValues).get_base_coord (baseline_tag_index); } 317 is_emptyOT::BaseScript318 bool is_empty () const { return !baseValues; } 319 sanitizeOT::BaseScript320 bool sanitize (hb_sanitize_context_t *c) const 321 { 322 TRACE_SANITIZE (this); 323 return_trace (likely (c->check_struct (this) && 324 baseValues.sanitize (c, this) && 325 defaultMinMax.sanitize (c, this) && 326 baseLangSysRecords.sanitize (c, this))); 327 } 328 329 protected: 330 OffsetTo<BaseValues> 331 baseValues; /* Offset to BaseValues table, from beginning 332 * of BaseScript table (may be NULL) */ 333 OffsetTo<MinMax> 334 defaultMinMax; /* Offset to MinMax table, from beginning of 335 * BaseScript table (may be NULL) */ 336 SortedArrayOf<BaseLangSysRecord> 337 baseLangSysRecords; 338 /* Number of BaseLangSysRecords 339 * defined — may be zero (0) */ 340 341 public: 342 DEFINE_SIZE_ARRAY (6, baseLangSysRecords); 343 }; 344 345 struct BaseScriptList; 346 struct BaseScriptRecord 347 { cmpOT::BaseScriptRecord348 static int cmp (const void *key_, const void *entry_) 349 { 350 hb_tag_t key = * (hb_tag_t *) key_; 351 const BaseScriptRecord &entry = * (const BaseScriptRecord *) entry_; 352 return key < (unsigned int) entry.baseScriptTag ? -1 : 353 key > (unsigned int) entry.baseScriptTag ? 1 : 354 0; 355 } 356 get_base_scriptOT::BaseScriptRecord357 const BaseScript &get_base_script (const BaseScriptList *list) const 358 { return list+baseScript; } 359 sanitizeOT::BaseScriptRecord360 bool sanitize (hb_sanitize_context_t *c, const void *base) const 361 { 362 TRACE_SANITIZE (this); 363 return_trace (likely (c->check_struct (this) && 364 baseScript.sanitize (c, base))); 365 } 366 367 protected: 368 Tag baseScriptTag; /* 4-byte script identification tag */ 369 OffsetTo<BaseScript> 370 baseScript; /* Offset to BaseScript table, from beginning 371 * of BaseScriptList */ 372 373 public: 374 DEFINE_SIZE_STATIC (6); 375 }; 376 377 struct BaseScriptList 378 { find_recordOT::BaseScriptList379 const BaseScriptRecord *find_record (hb_tag_t script) const 380 { 381 /* TODO Replace hb_bsearch() with .bsearch(). */ 382 return (const BaseScriptRecord *) hb_bsearch (&script, baseScriptRecords.arrayZ, 383 baseScriptRecords.len, 384 BaseScriptRecord::static_size, 385 BaseScriptRecord::cmp); 386 } 387 388 /* TODO: Or client should handle fallback? */ get_base_scriptOT::BaseScriptList389 const BaseScript &get_base_script (hb_tag_t script) const 390 { 391 const BaseScriptRecord *record = find_record (script); 392 if (!record) record = find_record ((hb_script_t) HB_TAG ('D','F','L','T')); 393 394 return record ? record->get_base_script (this) : Null (BaseScript); 395 } 396 sanitizeOT::BaseScriptList397 bool sanitize (hb_sanitize_context_t *c) const 398 { 399 TRACE_SANITIZE (this); 400 return_trace (c->check_struct (this) && 401 baseScriptRecords.sanitize (c, this)); 402 } 403 404 protected: 405 SortedArrayOf<BaseScriptRecord> 406 baseScriptRecords; 407 408 public: 409 DEFINE_SIZE_ARRAY (2, baseScriptRecords); 410 }; 411 412 struct Axis 413 { get_baselineOT::Axis414 bool get_baseline (hb_ot_layout_baseline_t baseline, 415 hb_tag_t script_tag, 416 hb_tag_t language_tag, 417 const BaseCoord **coord) const 418 { 419 const BaseScript &base_script = (this+baseScriptList).get_base_script (script_tag); 420 if (base_script.is_empty ()) return false; 421 422 if (likely (coord)) *coord = &base_script.get_base_coord ((this+baseTagList).bsearch (baseline)); 423 424 return true; 425 } 426 get_min_maxOT::Axis427 bool get_min_max (hb_tag_t script_tag, 428 hb_tag_t language_tag, 429 hb_tag_t feature_tag, 430 const BaseCoord **min_coord, 431 const BaseCoord **max_coord) const 432 { 433 const BaseScript &base_script = (this+baseScriptList).get_base_script (script_tag); 434 if (base_script.is_empty ()) return false; 435 436 base_script.get_min_max (language_tag).get_min_max (feature_tag, min_coord, max_coord); 437 438 return true; 439 } 440 sanitizeOT::Axis441 bool sanitize (hb_sanitize_context_t *c) const 442 { 443 TRACE_SANITIZE (this); 444 return_trace (likely (c->check_struct (this) && 445 (this+baseTagList).sanitize (c) && 446 (this+baseScriptList).sanitize (c))); 447 } 448 449 protected: 450 OffsetTo<SortedArrayOf<Tag> > 451 baseTagList; /* Offset to BaseTagList table, from beginning 452 * of Axis table (may be NULL) 453 * Array of 4-byte baseline identification tags — must 454 * be in alphabetical order */ 455 OffsetTo<BaseScriptList> 456 baseScriptList; /* Offset to BaseScriptList table, from beginning 457 * of Axis table 458 * Array of BaseScriptRecords, in alphabetical order 459 * by baseScriptTag */ 460 461 public: 462 DEFINE_SIZE_STATIC (4); 463 }; 464 465 struct BASE 466 { 467 enum { tableTag = HB_OT_TAG_BASE }; 468 get_axisOT::BASE469 const Axis &get_axis (hb_direction_t direction) const 470 { return HB_DIRECTION_IS_VERTICAL (direction) ? this+vAxis : this+hAxis; } 471 get_var_storeOT::BASE472 const VariationStore &get_var_store () const 473 { return version.to_int () < 0x00010001u ? Null (VariationStore) : this+varStore; } 474 get_baselineOT::BASE475 bool get_baseline (hb_font_t *font, 476 hb_ot_layout_baseline_t baseline, 477 hb_direction_t direction, 478 hb_tag_t script_tag, 479 hb_tag_t language_tag, 480 hb_position_t *base) const 481 { 482 const BaseCoord *base_coord; 483 if (!get_axis (direction).get_baseline (baseline, script_tag, language_tag, &base_coord)) 484 return false; 485 486 if (likely (base && base_coord)) *base = base_coord->get_coord (font, 487 get_var_store (), 488 direction); 489 return true; 490 } 491 492 /* TODO: Expose this separately sometime? */ get_min_maxOT::BASE493 bool get_min_max (hb_font_t *font, 494 hb_direction_t direction, 495 hb_tag_t script_tag, 496 hb_tag_t language_tag, 497 hb_tag_t feature_tag, 498 hb_position_t *min, 499 hb_position_t *max) 500 { 501 const BaseCoord *min_coord, *max_coord; 502 if (!get_axis (direction).get_min_max (script_tag, language_tag, feature_tag, 503 &min_coord, &max_coord)) 504 return false; 505 506 const VariationStore &var_store = get_var_store (); 507 if (likely (min && min_coord)) *min = min_coord->get_coord (font, var_store, direction); 508 if (likely (max && max_coord)) *max = max_coord->get_coord (font, var_store, direction); 509 return true; 510 } 511 sanitizeOT::BASE512 bool sanitize (hb_sanitize_context_t *c) const 513 { 514 TRACE_SANITIZE (this); 515 return_trace (likely (c->check_struct (this) && 516 likely (version.major == 1) && 517 hAxis.sanitize (c, this) && 518 vAxis.sanitize (c, this) && 519 (version.to_int () < 0x00010001u || varStore.sanitize (c, this)))); 520 } 521 522 protected: 523 FixedVersion<>version; /* Version of the BASE table */ 524 OffsetTo<Axis>hAxis; /* Offset to horizontal Axis table, from beginning 525 * of BASE table (may be NULL) */ 526 OffsetTo<Axis>vAxis; /* Offset to vertical Axis table, from beginning 527 * of BASE table (may be NULL) */ 528 LOffsetTo<VariationStore> 529 varStore; /* Offset to the table of Item Variation 530 * Store--from beginning of BASE 531 * header (may be NULL). Introduced 532 * in version 0x00010001. */ 533 public: 534 DEFINE_SIZE_MIN (8); 535 }; 536 537 538 } /* namespace OT */ 539 540 541 #endif /* HB_OT_LAYOUT_BASE_TABLE_HH */ 542