1 /* 2 * Copyright © 2019 Adobe Inc. 3 * Copyright © 2019 Ebrahim Byagowi 4 * 5 * This is part of HarfBuzz, a text shaping library. 6 * 7 * Permission is hereby granted, without written agreement and without 8 * license or royalty fees, to use, copy, modify, and distribute this 9 * software and its documentation for any purpose, provided that the 10 * above copyright notice and the following two paragraphs appear in 11 * all copies of this software. 12 * 13 * IN NO EVENT SHALL THE COPYRIGHT HOLDER BE LIABLE TO ANY PARTY FOR 14 * DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES 15 * ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN 16 * IF THE COPYRIGHT HOLDER HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH 17 * DAMAGE. 18 * 19 * THE COPYRIGHT HOLDER SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING, 20 * BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND 21 * FITNESS FOR A PARTICULAR PURPOSE. THE SOFTWARE PROVIDED HEREUNDER IS 22 * ON AN "AS IS" BASIS, AND THE COPYRIGHT HOLDER HAS NO OBLIGATION TO 23 * PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS. 24 * 25 * Adobe Author(s): Michiharu Ariza 26 */ 27 28 #ifndef HB_OT_VAR_GVAR_TABLE_HH 29 #define HB_OT_VAR_GVAR_TABLE_HH 30 31 #include "hb-open-type.hh" 32 33 /* 34 * gvar -- Glyph Variation Table 35 * https://docs.microsoft.com/en-us/typography/opentype/spec/gvar 36 */ 37 #define HB_OT_TAG_gvar HB_TAG('g','v','a','r') 38 39 namespace OT { 40 41 struct contour_point_t 42 { initOT::contour_point_t43 void init (float x_ = 0.f, float y_ = 0.f, bool is_end_point_ = false) 44 { flag = 0; x = x_; y = y_; is_end_point = is_end_point_; } 45 translateOT::contour_point_t46 void translate (const contour_point_t &p) { x += p.x; y += p.y; } 47 48 float x = 0.f; 49 float y = 0.f; 50 uint8_t flag = 0; 51 bool is_end_point = false; 52 }; 53 54 struct contour_point_vector_t : hb_vector_t<contour_point_t> 55 { extendOT::contour_point_vector_t56 void extend (const hb_array_t<contour_point_t> &a) 57 { 58 unsigned int old_len = length; 59 if (unlikely (!resize (old_len + a.length, false))) 60 return; 61 auto arrayZ = this->arrayZ + old_len; 62 unsigned count = a.length; 63 hb_memcpy (arrayZ, a.arrayZ, count * sizeof (arrayZ[0])); 64 } 65 transformOT::contour_point_vector_t66 void transform (const float (&matrix)[4]) 67 { 68 if (matrix[0] == 1.f && matrix[1] == 0.f && 69 matrix[2] == 0.f && matrix[3] == 1.f) 70 return; 71 auto arrayZ = this->arrayZ; 72 unsigned count = length; 73 for (unsigned i = 0; i < count; i++) 74 { 75 contour_point_t &p = arrayZ[i]; 76 float x_ = p.x * matrix[0] + p.y * matrix[2]; 77 p.y = p.x * matrix[1] + p.y * matrix[3]; 78 p.x = x_; 79 } 80 } 81 translateOT::contour_point_vector_t82 void translate (const contour_point_t& delta) 83 { 84 if (delta.x == 0.f && delta.y == 0.f) 85 return; 86 auto arrayZ = this->arrayZ; 87 unsigned count = length; 88 for (unsigned i = 0; i < count; i++) 89 arrayZ[i].translate (delta); 90 } 91 }; 92 93 /* https://docs.microsoft.com/en-us/typography/opentype/spec/otvarcommonformats#tuplevariationheader */ 94 struct TupleVariationHeader 95 { get_sizeOT::TupleVariationHeader96 unsigned get_size (unsigned axis_count) const 97 { return min_size + get_all_tuples (axis_count).get_size (); } 98 get_data_sizeOT::TupleVariationHeader99 unsigned get_data_size () const { return varDataSize; } 100 get_nextOT::TupleVariationHeader101 const TupleVariationHeader &get_next (unsigned axis_count) const 102 { return StructAtOffset<TupleVariationHeader> (this, get_size (axis_count)); } 103 calculate_scalarOT::TupleVariationHeader104 float calculate_scalar (hb_array_t<int> coords, unsigned int coord_count, 105 const hb_array_t<const F2DOT14> shared_tuples) const 106 { 107 hb_array_t<const F2DOT14> peak_tuple; 108 109 if (has_peak ()) 110 peak_tuple = get_peak_tuple (coord_count); 111 else 112 { 113 unsigned int index = get_index (); 114 if (unlikely (index * coord_count >= shared_tuples.length)) 115 return 0.f; 116 peak_tuple = shared_tuples.sub_array (coord_count * index, coord_count); 117 } 118 119 hb_array_t<const F2DOT14> start_tuple; 120 hb_array_t<const F2DOT14> end_tuple; 121 if (has_intermediate ()) 122 { 123 start_tuple = get_start_tuple (coord_count); 124 end_tuple = get_end_tuple (coord_count); 125 } 126 127 float scalar = 1.f; 128 for (unsigned int i = 0; i < coord_count; i++) 129 { 130 int v = coords[i]; 131 int peak = peak_tuple[i]; 132 if (!peak || v == peak) continue; 133 134 if (has_intermediate ()) 135 { 136 int start = start_tuple[i]; 137 int end = end_tuple[i]; 138 if (unlikely (start > peak || peak > end || 139 (start < 0 && end > 0 && peak))) continue; 140 if (v < start || v > end) return 0.f; 141 if (v < peak) 142 { if (peak != start) scalar *= (float) (v - start) / (peak - start); } 143 else 144 { if (peak != end) scalar *= (float) (end - v) / (end - peak); } 145 } 146 else if (!v || v < hb_min (0, peak) || v > hb_max (0, peak)) return 0.f; 147 else 148 scalar *= (float) v / peak; 149 } 150 return scalar; 151 } 152 has_peakOT::TupleVariationHeader153 bool has_peak () const { return tupleIndex & TuppleIndex::EmbeddedPeakTuple; } has_intermediateOT::TupleVariationHeader154 bool has_intermediate () const { return tupleIndex & TuppleIndex::IntermediateRegion; } has_private_pointsOT::TupleVariationHeader155 bool has_private_points () const { return tupleIndex & TuppleIndex::PrivatePointNumbers; } get_indexOT::TupleVariationHeader156 unsigned get_index () const { return tupleIndex & TuppleIndex::TupleIndexMask; } 157 158 protected: 159 struct TuppleIndex : HBUINT16 160 { 161 enum Flags { 162 EmbeddedPeakTuple = 0x8000u, 163 IntermediateRegion = 0x4000u, 164 PrivatePointNumbers = 0x2000u, 165 TupleIndexMask = 0x0FFFu 166 }; 167 168 DEFINE_SIZE_STATIC (2); 169 }; 170 get_all_tuplesOT::TupleVariationHeader171 hb_array_t<const F2DOT14> get_all_tuples (unsigned axis_count) const 172 { return StructAfter<UnsizedArrayOf<F2DOT14>> (tupleIndex).as_array ((has_peak () + has_intermediate () * 2) * axis_count); } get_peak_tupleOT::TupleVariationHeader173 hb_array_t<const F2DOT14> get_peak_tuple (unsigned axis_count) const 174 { return get_all_tuples (axis_count).sub_array (0, axis_count); } get_start_tupleOT::TupleVariationHeader175 hb_array_t<const F2DOT14> get_start_tuple (unsigned axis_count) const 176 { return get_all_tuples (axis_count).sub_array (has_peak () * axis_count, axis_count); } get_end_tupleOT::TupleVariationHeader177 hb_array_t<const F2DOT14> get_end_tuple (unsigned axis_count) const 178 { return get_all_tuples (axis_count).sub_array (has_peak () * axis_count + axis_count, axis_count); } 179 180 HBUINT16 varDataSize; /* The size in bytes of the serialized 181 * data for this tuple variation table. */ 182 TuppleIndex tupleIndex; /* A packed field. The high 4 bits are flags (see below). 183 The low 12 bits are an index into a shared tuple 184 records array. */ 185 /* UnsizedArrayOf<F2DOT14> peakTuple - optional */ 186 /* Peak tuple record for this tuple variation table — optional, 187 * determined by flags in the tupleIndex value. 188 * 189 * Note that this must always be included in the 'cvar' table. */ 190 /* UnsizedArrayOf<F2DOT14> intermediateStartTuple - optional */ 191 /* Intermediate start tuple record for this tuple variation table — optional, 192 determined by flags in the tupleIndex value. */ 193 /* UnsizedArrayOf<F2DOT14> intermediateEndTuple - optional */ 194 /* Intermediate end tuple record for this tuple variation table — optional, 195 * determined by flags in the tupleIndex value. */ 196 public: 197 DEFINE_SIZE_MIN (4); 198 }; 199 200 struct GlyphVariationData 201 { get_tuple_var_headerOT::GlyphVariationData202 const TupleVariationHeader &get_tuple_var_header (void) const 203 { return StructAfter<TupleVariationHeader> (data); } 204 205 struct tuple_iterator_t 206 { initOT::GlyphVariationData::tuple_iterator_t207 void init (hb_bytes_t var_data_bytes_, unsigned int axis_count_) 208 { 209 var_data_bytes = var_data_bytes_; 210 var_data = var_data_bytes_.as<GlyphVariationData> (); 211 index = 0; 212 axis_count = axis_count_; 213 current_tuple = &var_data->get_tuple_var_header (); 214 data_offset = 0; 215 } 216 get_shared_indicesOT::GlyphVariationData::tuple_iterator_t217 bool get_shared_indices (hb_vector_t<unsigned int> &shared_indices /* OUT */) 218 { 219 if (var_data->has_shared_point_numbers ()) 220 { 221 const HBUINT8 *base = &(var_data+var_data->data); 222 const HBUINT8 *p = base; 223 if (!unpack_points (p, shared_indices, (const HBUINT8 *) (var_data_bytes.arrayZ + var_data_bytes.length))) return false; 224 data_offset = p - base; 225 } 226 return true; 227 } 228 is_validOT::GlyphVariationData::tuple_iterator_t229 bool is_valid () const 230 { 231 return (index < var_data->tupleVarCount.get_count ()) && 232 var_data_bytes.check_range (current_tuple, TupleVariationHeader::min_size) && 233 var_data_bytes.check_range (current_tuple, hb_max (current_tuple->get_data_size (), 234 current_tuple->get_size (axis_count))); 235 } 236 move_to_nextOT::GlyphVariationData::tuple_iterator_t237 bool move_to_next () 238 { 239 data_offset += current_tuple->get_data_size (); 240 current_tuple = ¤t_tuple->get_next (axis_count); 241 index++; 242 return is_valid (); 243 } 244 get_serialized_dataOT::GlyphVariationData::tuple_iterator_t245 const HBUINT8 *get_serialized_data () const 246 { return &(var_data+var_data->data) + data_offset; } 247 248 private: 249 const GlyphVariationData *var_data; 250 unsigned int index; 251 unsigned int axis_count; 252 unsigned int data_offset; 253 254 public: 255 hb_bytes_t var_data_bytes; 256 const TupleVariationHeader *current_tuple; 257 }; 258 get_tuple_iteratorOT::GlyphVariationData259 static bool get_tuple_iterator (hb_bytes_t var_data_bytes, unsigned axis_count, 260 hb_vector_t<unsigned int> &shared_indices /* OUT */, 261 tuple_iterator_t *iterator /* OUT */) 262 { 263 iterator->init (var_data_bytes, axis_count); 264 if (!iterator->get_shared_indices (shared_indices)) 265 return false; 266 return iterator->is_valid (); 267 } 268 has_shared_point_numbersOT::GlyphVariationData269 bool has_shared_point_numbers () const { return tupleVarCount.has_shared_point_numbers (); } 270 unpack_pointsOT::GlyphVariationData271 static bool unpack_points (const HBUINT8 *&p /* IN/OUT */, 272 hb_vector_t<unsigned int> &points /* OUT */, 273 const HBUINT8 *end) 274 { 275 enum packed_point_flag_t 276 { 277 POINTS_ARE_WORDS = 0x80, 278 POINT_RUN_COUNT_MASK = 0x7F 279 }; 280 281 if (unlikely (p + 1 > end)) return false; 282 283 unsigned count = *p++; 284 if (count & POINTS_ARE_WORDS) 285 { 286 if (unlikely (p + 1 > end)) return false; 287 count = ((count & POINT_RUN_COUNT_MASK) << 8) | *p++; 288 } 289 if (unlikely (!points.resize (count, false))) return false; 290 291 unsigned n = 0; 292 unsigned i = 0; 293 while (i < count) 294 { 295 if (unlikely (p + 1 > end)) return false; 296 unsigned control = *p++; 297 unsigned run_count = (control & POINT_RUN_COUNT_MASK) + 1; 298 if (unlikely (i + run_count > count)) return false; 299 unsigned j; 300 if (control & POINTS_ARE_WORDS) 301 { 302 if (unlikely (p + run_count * HBUINT16::static_size > end)) return false; 303 for (j = 0; j < run_count; j++, i++) 304 { 305 n += *(const HBUINT16 *)p; 306 points.arrayZ[i] = n; 307 p += HBUINT16::static_size; 308 } 309 } 310 else 311 { 312 if (unlikely (p + run_count > end)) return false; 313 for (j = 0; j < run_count; j++, i++) 314 { 315 n += *p++; 316 points.arrayZ[i] = n; 317 } 318 } 319 } 320 return true; 321 } 322 unpack_deltasOT::GlyphVariationData323 static bool unpack_deltas (const HBUINT8 *&p /* IN/OUT */, 324 hb_vector_t<int> &deltas /* IN/OUT */, 325 const HBUINT8 *end) 326 { 327 enum packed_delta_flag_t 328 { 329 DELTAS_ARE_ZERO = 0x80, 330 DELTAS_ARE_WORDS = 0x40, 331 DELTA_RUN_COUNT_MASK = 0x3F 332 }; 333 334 unsigned i = 0; 335 unsigned count = deltas.length; 336 while (i < count) 337 { 338 if (unlikely (p + 1 > end)) return false; 339 unsigned control = *p++; 340 unsigned run_count = (control & DELTA_RUN_COUNT_MASK) + 1; 341 if (unlikely (i + run_count > count)) return false; 342 unsigned j; 343 if (control & DELTAS_ARE_ZERO) 344 { 345 for (j = 0; j < run_count; j++, i++) 346 deltas.arrayZ[i] = 0; 347 } 348 else if (control & DELTAS_ARE_WORDS) 349 { 350 if (unlikely (p + run_count * HBUINT16::static_size > end)) return false; 351 for (j = 0; j < run_count; j++, i++) 352 { 353 deltas.arrayZ[i] = * (const HBINT16 *) p; 354 p += HBUINT16::static_size; 355 } 356 } 357 else 358 { 359 if (unlikely (p + run_count > end)) return false; 360 for (j = 0; j < run_count; j++, i++) 361 { 362 deltas.arrayZ[i] = * (const HBINT8 *) p++; 363 } 364 } 365 } 366 return true; 367 } 368 has_dataOT::GlyphVariationData369 bool has_data () const { return tupleVarCount; } 370 371 protected: 372 struct TupleVarCount : HBUINT16 373 { has_shared_point_numbersOT::GlyphVariationData::TupleVarCount374 bool has_shared_point_numbers () const { return ((*this) & SharedPointNumbers); } get_countOT::GlyphVariationData::TupleVarCount375 unsigned int get_count () const { return (*this) & CountMask; } 376 377 protected: 378 enum Flags 379 { 380 SharedPointNumbers= 0x8000u, 381 CountMask = 0x0FFFu 382 }; 383 public: 384 DEFINE_SIZE_STATIC (2); 385 }; 386 387 TupleVarCount tupleVarCount; /* A packed field. The high 4 bits are flags, and the 388 * low 12 bits are the number of tuple variation tables 389 * for this glyph. The number of tuple variation tables 390 * can be any number between 1 and 4095. */ 391 Offset16To<HBUINT8> 392 data; /* Offset from the start of the GlyphVariationData table 393 * to the serialized data. */ 394 /* TupleVariationHeader tupleVariationHeaders[] *//* Array of tuple variation headers. */ 395 public: 396 DEFINE_SIZE_MIN (4); 397 }; 398 399 struct gvar 400 { 401 static constexpr hb_tag_t tableTag = HB_OT_TAG_gvar; 402 sanitize_shallowOT::gvar403 bool sanitize_shallow (hb_sanitize_context_t *c) const 404 { 405 TRACE_SANITIZE (this); 406 return_trace (c->check_struct (this) && (version.major == 1) && 407 sharedTuples.sanitize (c, this, axisCount * sharedTupleCount) && 408 (is_long_offset () ? 409 c->check_array (get_long_offset_array (), glyphCount+1) : 410 c->check_array (get_short_offset_array (), glyphCount+1))); 411 } 412 413 /* GlyphVariationData not sanitized here; must be checked while accessing each glyph variation data */ sanitizeOT::gvar414 bool sanitize (hb_sanitize_context_t *c) const 415 { return sanitize_shallow (c); } 416 subsetOT::gvar417 bool subset (hb_subset_context_t *c) const 418 { 419 TRACE_SUBSET (this); 420 421 gvar *out = c->serializer->allocate_min<gvar> (); 422 if (unlikely (!out)) return_trace (false); 423 424 out->version.major = 1; 425 out->version.minor = 0; 426 out->axisCount = axisCount; 427 out->sharedTupleCount = sharedTupleCount; 428 429 unsigned int num_glyphs = c->plan->num_output_glyphs (); 430 out->glyphCount = num_glyphs; 431 432 unsigned int subset_data_size = 0; 433 for (hb_codepoint_t gid = (c->plan->flags & HB_SUBSET_FLAGS_NOTDEF_OUTLINE) ? 0 : 1; 434 gid < num_glyphs; 435 gid++) 436 { 437 hb_codepoint_t old_gid; 438 if (!c->plan->old_gid_for_new_gid (gid, &old_gid)) continue; 439 subset_data_size += get_glyph_var_data_bytes (c->source_blob, old_gid).length; 440 } 441 442 bool long_offset = subset_data_size & ~0xFFFFu; 443 out->flags = long_offset ? 1 : 0; 444 445 HBUINT8 *subset_offsets = c->serializer->allocate_size<HBUINT8> ((long_offset ? 4 : 2) * (num_glyphs + 1)); 446 if (!subset_offsets) return_trace (false); 447 448 /* shared tuples */ 449 if (!sharedTupleCount || !sharedTuples) 450 out->sharedTuples = 0; 451 else 452 { 453 unsigned int shared_tuple_size = F2DOT14::static_size * axisCount * sharedTupleCount; 454 F2DOT14 *tuples = c->serializer->allocate_size<F2DOT14> (shared_tuple_size); 455 if (!tuples) return_trace (false); 456 out->sharedTuples = (char *) tuples - (char *) out; 457 hb_memcpy (tuples, this+sharedTuples, shared_tuple_size); 458 } 459 460 char *subset_data = c->serializer->allocate_size<char> (subset_data_size); 461 if (!subset_data) return_trace (false); 462 out->dataZ = subset_data - (char *) out; 463 464 unsigned int glyph_offset = 0; 465 for (hb_codepoint_t gid = (c->plan->flags & HB_SUBSET_FLAGS_NOTDEF_OUTLINE) ? 0 : 1; 466 gid < num_glyphs; 467 gid++) 468 { 469 hb_codepoint_t old_gid; 470 hb_bytes_t var_data_bytes = c->plan->old_gid_for_new_gid (gid, &old_gid) 471 ? get_glyph_var_data_bytes (c->source_blob, old_gid) 472 : hb_bytes_t (); 473 474 if (long_offset) 475 ((HBUINT32 *) subset_offsets)[gid] = glyph_offset; 476 else 477 ((HBUINT16 *) subset_offsets)[gid] = glyph_offset / 2; 478 479 if (var_data_bytes.length > 0) 480 hb_memcpy (subset_data, var_data_bytes.arrayZ, var_data_bytes.length); 481 subset_data += var_data_bytes.length; 482 glyph_offset += var_data_bytes.length; 483 } 484 if (long_offset) 485 ((HBUINT32 *) subset_offsets)[num_glyphs] = glyph_offset; 486 else 487 ((HBUINT16 *) subset_offsets)[num_glyphs] = glyph_offset / 2; 488 489 return_trace (true); 490 } 491 492 protected: get_glyph_var_data_bytesOT::gvar493 const hb_bytes_t get_glyph_var_data_bytes (hb_blob_t *blob, hb_codepoint_t glyph) const 494 { 495 unsigned start_offset = get_offset (glyph); 496 unsigned end_offset = get_offset (glyph+1); 497 if (unlikely (end_offset < start_offset)) return hb_bytes_t (); 498 unsigned length = end_offset - start_offset; 499 hb_bytes_t var_data = blob->as_bytes ().sub_array (((unsigned) dataZ) + start_offset, length); 500 return likely (var_data.length >= GlyphVariationData::min_size) ? var_data : hb_bytes_t (); 501 } 502 is_long_offsetOT::gvar503 bool is_long_offset () const { return flags & 1; } 504 get_offsetOT::gvar505 unsigned get_offset (unsigned i) const 506 { 507 if (unlikely (i > glyphCount)) return 0; 508 _hb_compiler_memory_r_barrier (); 509 return is_long_offset () ? get_long_offset_array ()[i] : get_short_offset_array ()[i] * 2; 510 } 511 get_long_offset_arrayOT::gvar512 const HBUINT32 * get_long_offset_array () const { return (const HBUINT32 *) &offsetZ; } get_short_offset_arrayOT::gvar513 const HBUINT16 *get_short_offset_array () const { return (const HBUINT16 *) &offsetZ; } 514 515 public: 516 struct accelerator_t 517 { accelerator_tOT::gvar::accelerator_t518 accelerator_t (hb_face_t *face) 519 { table = hb_sanitize_context_t ().reference_table<gvar> (face); } ~accelerator_tOT::gvar::accelerator_t520 ~accelerator_t () { table.destroy (); } 521 522 private: 523 infer_deltaOT::gvar::accelerator_t524 static float infer_delta (const hb_array_t<contour_point_t> points, 525 const hb_array_t<contour_point_t> deltas, 526 unsigned int target, unsigned int prev, unsigned int next, 527 float contour_point_t::*m) 528 { 529 float target_val = points.arrayZ[target].*m; 530 float prev_val = points.arrayZ[prev].*m; 531 float next_val = points.arrayZ[next].*m; 532 float prev_delta = deltas.arrayZ[prev].*m; 533 float next_delta = deltas.arrayZ[next].*m; 534 535 if (prev_val == next_val) 536 return (prev_delta == next_delta) ? prev_delta : 0.f; 537 else if (target_val <= hb_min (prev_val, next_val)) 538 return (prev_val < next_val) ? prev_delta : next_delta; 539 else if (target_val >= hb_max (prev_val, next_val)) 540 return (prev_val > next_val) ? prev_delta : next_delta; 541 542 /* linear interpolation */ 543 float r = (target_val - prev_val) / (next_val - prev_val); 544 return prev_delta + r * (next_delta - prev_delta); 545 } 546 next_indexOT::gvar::accelerator_t547 static unsigned int next_index (unsigned int i, unsigned int start, unsigned int end) 548 { return (i >= end) ? start : (i + 1); } 549 550 public: apply_deltas_to_pointsOT::gvar::accelerator_t551 bool apply_deltas_to_points (hb_codepoint_t glyph, 552 hb_array_t<int> coords, 553 const hb_array_t<contour_point_t> points) const 554 { 555 if (!coords) return true; 556 557 if (unlikely (glyph >= table->glyphCount)) return true; 558 559 hb_bytes_t var_data_bytes = table->get_glyph_var_data_bytes (table.get_blob (), glyph); 560 if (!var_data_bytes.as<GlyphVariationData> ()->has_data ()) return true; 561 hb_vector_t<unsigned int> shared_indices; 562 GlyphVariationData::tuple_iterator_t iterator; 563 if (!GlyphVariationData::get_tuple_iterator (var_data_bytes, table->axisCount, 564 shared_indices, &iterator)) 565 return true; /* so isn't applied at all */ 566 567 /* Save original points for inferred delta calculation */ 568 contour_point_vector_t orig_points_vec; 569 orig_points_vec.extend (points); 570 if (unlikely (orig_points_vec.in_error ())) return false; 571 auto orig_points = orig_points_vec.as_array (); 572 573 contour_point_vector_t deltas_vec; /* flag is used to indicate referenced point */ 574 if (unlikely (!deltas_vec.resize (points.length, false))) return false; 575 auto deltas = deltas_vec.as_array (); 576 577 hb_vector_t<unsigned> end_points; 578 for (unsigned i = 0; i < points.length; ++i) 579 if (points.arrayZ[i].is_end_point) 580 end_points.push (i); 581 582 unsigned num_coords = table->axisCount; 583 hb_array_t<const F2DOT14> shared_tuples = (table+table->sharedTuples).as_array (table->sharedTupleCount * table->axisCount); 584 585 hb_vector_t<unsigned int> private_indices; 586 hb_vector_t<int> x_deltas; 587 hb_vector_t<int> y_deltas; 588 do 589 { 590 float scalar = iterator.current_tuple->calculate_scalar (coords, num_coords, shared_tuples); 591 if (scalar == 0.f) continue; 592 const HBUINT8 *p = iterator.get_serialized_data (); 593 unsigned int length = iterator.current_tuple->get_data_size (); 594 if (unlikely (!iterator.var_data_bytes.check_range (p, length))) 595 return false; 596 597 const HBUINT8 *end = p + length; 598 599 bool has_private_points = iterator.current_tuple->has_private_points (); 600 if (has_private_points && 601 !GlyphVariationData::unpack_points (p, private_indices, end)) 602 return false; 603 const hb_array_t<unsigned int> &indices = has_private_points ? private_indices : shared_indices; 604 605 bool apply_to_all = (indices.length == 0); 606 unsigned int num_deltas = apply_to_all ? points.length : indices.length; 607 if (unlikely (!x_deltas.resize (num_deltas, false))) return false; 608 if (unlikely (!GlyphVariationData::unpack_deltas (p, x_deltas, end))) return false; 609 if (unlikely (!y_deltas.resize (num_deltas, false))) return false; 610 if (unlikely (!GlyphVariationData::unpack_deltas (p, y_deltas, end))) return false; 611 612 hb_memset (deltas.arrayZ, 0, deltas.get_size ()); 613 614 unsigned ref_points = 0; 615 if (scalar != 1.0f) 616 for (unsigned int i = 0; i < num_deltas; i++) 617 { 618 unsigned int pt_index = apply_to_all ? i : indices[i]; 619 if (unlikely (pt_index >= deltas.length)) continue; 620 auto &delta = deltas.arrayZ[pt_index]; 621 ref_points += !delta.flag; 622 delta.flag = 1; /* this point is referenced, i.e., explicit deltas specified */ 623 delta.x += x_deltas.arrayZ[i] * scalar; 624 delta.y += y_deltas.arrayZ[i] * scalar; 625 } 626 else 627 for (unsigned int i = 0; i < num_deltas; i++) 628 { 629 unsigned int pt_index = apply_to_all ? i : indices[i]; 630 if (unlikely (pt_index >= deltas.length)) continue; 631 auto &delta = deltas.arrayZ[pt_index]; 632 ref_points += !delta.flag; 633 delta.flag = 1; /* this point is referenced, i.e., explicit deltas specified */ 634 delta.x += x_deltas.arrayZ[i]; 635 delta.y += y_deltas.arrayZ[i]; 636 } 637 638 /* infer deltas for unreferenced points */ 639 if (ref_points && ref_points < orig_points.length) 640 { 641 unsigned start_point = 0; 642 for (unsigned c = 0; c < end_points.length; c++) 643 { 644 unsigned end_point = end_points.arrayZ[c]; 645 646 /* Check the number of unreferenced points in a contour. If no unref points or no ref points, nothing to do. */ 647 unsigned unref_count = 0; 648 for (unsigned i = start_point; i < end_point + 1; i++) 649 unref_count += deltas.arrayZ[i].flag; 650 unref_count = (end_point - start_point + 1) - unref_count; 651 652 unsigned j = start_point; 653 if (unref_count == 0 || unref_count > end_point - start_point) 654 goto no_more_gaps; 655 656 for (;;) 657 { 658 /* Locate the next gap of unreferenced points between two referenced points prev and next. 659 * Note that a gap may wrap around at left (start_point) and/or at right (end_point). 660 */ 661 unsigned int prev, next, i; 662 for (;;) 663 { 664 i = j; 665 j = next_index (i, start_point, end_point); 666 if (deltas.arrayZ[i].flag && !deltas.arrayZ[j].flag) break; 667 } 668 prev = j = i; 669 for (;;) 670 { 671 i = j; 672 j = next_index (i, start_point, end_point); 673 if (!deltas.arrayZ[i].flag && deltas.arrayZ[j].flag) break; 674 } 675 next = j; 676 /* Infer deltas for all unref points in the gap between prev and next */ 677 i = prev; 678 for (;;) 679 { 680 i = next_index (i, start_point, end_point); 681 if (i == next) break; 682 deltas.arrayZ[i].x = infer_delta (orig_points, deltas, i, prev, next, &contour_point_t::x); 683 deltas.arrayZ[i].y = infer_delta (orig_points, deltas, i, prev, next, &contour_point_t::y); 684 if (--unref_count == 0) goto no_more_gaps; 685 } 686 } 687 no_more_gaps: 688 start_point = end_point + 1; 689 } 690 } 691 692 /* apply specified / inferred deltas to points */ 693 for (unsigned int i = 0; i < points.length; i++) 694 { 695 points.arrayZ[i].x += deltas.arrayZ[i].x; 696 points.arrayZ[i].y += deltas.arrayZ[i].y; 697 } 698 } while (iterator.move_to_next ()); 699 700 return true; 701 } 702 get_axis_countOT::gvar::accelerator_t703 unsigned int get_axis_count () const { return table->axisCount; } 704 705 private: 706 hb_blob_ptr_t<gvar> table; 707 }; 708 709 protected: 710 FixedVersion<>version; /* Version number of the glyph variations table 711 * Set to 0x00010000u. */ 712 HBUINT16 axisCount; /* The number of variation axes for this font. This must be 713 * the same number as axisCount in the 'fvar' table. */ 714 HBUINT16 sharedTupleCount; 715 /* The number of shared tuple records. Shared tuple records 716 * can be referenced within glyph variation data tables for 717 * multiple glyphs, as opposed to other tuple records stored 718 * directly within a glyph variation data table. */ 719 NNOffset32To<UnsizedArrayOf<F2DOT14>> 720 sharedTuples; /* Offset from the start of this table to the shared tuple records. 721 * Array of tuple records shared across all glyph variation data tables. */ 722 HBUINT16 glyphCount; /* The number of glyphs in this font. This must match the number of 723 * glyphs stored elsewhere in the font. */ 724 HBUINT16 flags; /* Bit-field that gives the format of the offset array that follows. 725 * If bit 0 is clear, the offsets are uint16; if bit 0 is set, the 726 * offsets are uint32. */ 727 Offset32To<GlyphVariationData> 728 dataZ; /* Offset from the start of this table to the array of 729 * GlyphVariationData tables. */ 730 UnsizedArrayOf<HBUINT8> 731 offsetZ; /* Offsets from the start of the GlyphVariationData array 732 * to each GlyphVariationData table. */ 733 public: 734 DEFINE_SIZE_ARRAY (20, offsetZ); 735 }; 736 737 struct gvar_accelerator_t : gvar::accelerator_t { gvar_accelerator_tOT::gvar_accelerator_t738 gvar_accelerator_t (hb_face_t *face) : gvar::accelerator_t (face) {} 739 }; 740 741 } /* namespace OT */ 742 743 #endif /* HB_OT_VAR_GVAR_TABLE_HH */ 744