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 uint8_t flag; 49 float x, y; 50 bool is_end_point; 51 }; 52 53 struct contour_point_vector_t : hb_vector_t<contour_point_t> 54 { extendOT::contour_point_vector_t55 void extend (const hb_array_t<contour_point_t> &a) 56 { 57 unsigned int old_len = length; 58 resize (old_len + a.length); 59 for (unsigned int i = 0; i < a.length; i++) 60 (*this)[old_len + i] = a[i]; 61 } 62 transformOT::contour_point_vector_t63 void transform (const float (&matrix)[4]) 64 { 65 for (unsigned int i = 0; i < length; i++) 66 { 67 contour_point_t &p = (*this)[i]; 68 float x_ = p.x * matrix[0] + p.y * matrix[2]; 69 p.y = p.x * matrix[1] + p.y * matrix[3]; 70 p.x = x_; 71 } 72 } 73 translateOT::contour_point_vector_t74 void translate (const contour_point_t& delta) 75 { 76 for (unsigned int i = 0; i < length; i++) 77 (*this)[i].translate (delta); 78 } 79 }; 80 81 /* https://docs.microsoft.com/en-us/typography/opentype/spec/otvarcommonformats#tuplevariationheader */ 82 struct TupleVariationHeader 83 { get_sizeOT::TupleVariationHeader84 unsigned get_size (unsigned axis_count) const 85 { return min_size + get_all_tuples (axis_count).get_size (); } 86 get_data_sizeOT::TupleVariationHeader87 unsigned get_data_size () const { return varDataSize; } 88 get_nextOT::TupleVariationHeader89 const TupleVariationHeader &get_next (unsigned axis_count) const 90 { return StructAtOffset<TupleVariationHeader> (this, get_size (axis_count)); } 91 calculate_scalarOT::TupleVariationHeader92 float calculate_scalar (const int *coords, unsigned int coord_count, 93 const hb_array_t<const F2DOT14> shared_tuples) const 94 { 95 hb_array_t<const F2DOT14> peak_tuple; 96 97 if (has_peak ()) 98 peak_tuple = get_peak_tuple (coord_count); 99 else 100 { 101 unsigned int index = get_index (); 102 if (unlikely (index * coord_count >= shared_tuples.length)) 103 return 0.f; 104 peak_tuple = shared_tuples.sub_array (coord_count * index, coord_count); 105 } 106 107 hb_array_t<const F2DOT14> start_tuple; 108 hb_array_t<const F2DOT14> end_tuple; 109 if (has_intermediate ()) 110 { 111 start_tuple = get_start_tuple (coord_count); 112 end_tuple = get_end_tuple (coord_count); 113 } 114 115 float scalar = 1.f; 116 for (unsigned int i = 0; i < coord_count; i++) 117 { 118 int v = coords[i]; 119 int peak = peak_tuple[i]; 120 if (!peak || v == peak) continue; 121 122 if (has_intermediate ()) 123 { 124 int start = start_tuple[i]; 125 int end = end_tuple[i]; 126 if (unlikely (start > peak || peak > end || 127 (start < 0 && end > 0 && peak))) continue; 128 if (v < start || v > end) return 0.f; 129 if (v < peak) 130 { if (peak != start) scalar *= (float) (v - start) / (peak - start); } 131 else 132 { if (peak != end) scalar *= (float) (end - v) / (end - peak); } 133 } 134 else if (!v || v < hb_min (0, peak) || v > hb_max (0, peak)) return 0.f; 135 else 136 scalar *= (float) v / peak; 137 } 138 return scalar; 139 } 140 has_peakOT::TupleVariationHeader141 bool has_peak () const { return tupleIndex & TuppleIndex::EmbeddedPeakTuple; } has_intermediateOT::TupleVariationHeader142 bool has_intermediate () const { return tupleIndex & TuppleIndex::IntermediateRegion; } has_private_pointsOT::TupleVariationHeader143 bool has_private_points () const { return tupleIndex & TuppleIndex::PrivatePointNumbers; } get_indexOT::TupleVariationHeader144 unsigned get_index () const { return tupleIndex & TuppleIndex::TupleIndexMask; } 145 146 protected: 147 struct TuppleIndex : HBUINT16 148 { 149 enum Flags { 150 EmbeddedPeakTuple = 0x8000u, 151 IntermediateRegion = 0x4000u, 152 PrivatePointNumbers = 0x2000u, 153 TupleIndexMask = 0x0FFFu 154 }; 155 156 DEFINE_SIZE_STATIC (2); 157 }; 158 get_all_tuplesOT::TupleVariationHeader159 hb_array_t<const F2DOT14> get_all_tuples (unsigned axis_count) const 160 { return StructAfter<UnsizedArrayOf<F2DOT14>> (tupleIndex).as_array ((has_peak () + has_intermediate () * 2) * axis_count); } get_peak_tupleOT::TupleVariationHeader161 hb_array_t<const F2DOT14> get_peak_tuple (unsigned axis_count) const 162 { return get_all_tuples (axis_count).sub_array (0, axis_count); } get_start_tupleOT::TupleVariationHeader163 hb_array_t<const F2DOT14> get_start_tuple (unsigned axis_count) const 164 { return get_all_tuples (axis_count).sub_array (has_peak () * axis_count, axis_count); } get_end_tupleOT::TupleVariationHeader165 hb_array_t<const F2DOT14> get_end_tuple (unsigned axis_count) const 166 { return get_all_tuples (axis_count).sub_array (has_peak () * axis_count + axis_count, axis_count); } 167 168 HBUINT16 varDataSize; /* The size in bytes of the serialized 169 * data for this tuple variation table. */ 170 TuppleIndex tupleIndex; /* A packed field. The high 4 bits are flags (see below). 171 The low 12 bits are an index into a shared tuple 172 records array. */ 173 /* UnsizedArrayOf<F2DOT14> peakTuple - optional */ 174 /* Peak tuple record for this tuple variation table — optional, 175 * determined by flags in the tupleIndex value. 176 * 177 * Note that this must always be included in the 'cvar' table. */ 178 /* UnsizedArrayOf<F2DOT14> intermediateStartTuple - optional */ 179 /* Intermediate start tuple record for this tuple variation table — optional, 180 determined by flags in the tupleIndex value. */ 181 /* UnsizedArrayOf<F2DOT14> intermediateEndTuple - optional */ 182 /* Intermediate end tuple record for this tuple variation table — optional, 183 * determined by flags in the tupleIndex value. */ 184 public: 185 DEFINE_SIZE_MIN (4); 186 }; 187 188 struct GlyphVariationData 189 { get_tuple_var_headerOT::GlyphVariationData190 const TupleVariationHeader &get_tuple_var_header (void) const 191 { return StructAfter<TupleVariationHeader> (data); } 192 193 struct tuple_iterator_t 194 { initOT::GlyphVariationData::tuple_iterator_t195 void init (hb_bytes_t var_data_bytes_, unsigned int axis_count_) 196 { 197 var_data_bytes = var_data_bytes_; 198 var_data = var_data_bytes_.as<GlyphVariationData> (); 199 index = 0; 200 axis_count = axis_count_; 201 current_tuple = &var_data->get_tuple_var_header (); 202 data_offset = 0; 203 } 204 get_shared_indicesOT::GlyphVariationData::tuple_iterator_t205 bool get_shared_indices (hb_vector_t<unsigned int> &shared_indices /* OUT */) 206 { 207 if (var_data->has_shared_point_numbers ()) 208 { 209 const HBUINT8 *base = &(var_data+var_data->data); 210 const HBUINT8 *p = base; 211 if (!unpack_points (p, shared_indices, var_data_bytes)) return false; 212 data_offset = p - base; 213 } 214 return true; 215 } 216 is_validOT::GlyphVariationData::tuple_iterator_t217 bool is_valid () const 218 { 219 return (index < var_data->tupleVarCount.get_count ()) && 220 var_data_bytes.check_range (current_tuple, TupleVariationHeader::min_size) && 221 var_data_bytes.check_range (current_tuple, hb_max (current_tuple->get_data_size (), current_tuple->get_size (axis_count))) && 222 current_tuple->get_size (axis_count); 223 } 224 move_to_nextOT::GlyphVariationData::tuple_iterator_t225 bool move_to_next () 226 { 227 data_offset += current_tuple->get_data_size (); 228 current_tuple = ¤t_tuple->get_next (axis_count); 229 index++; 230 return is_valid (); 231 } 232 get_serialized_dataOT::GlyphVariationData::tuple_iterator_t233 const HBUINT8 *get_serialized_data () const 234 { return &(var_data+var_data->data) + data_offset; } 235 236 private: 237 const GlyphVariationData *var_data; 238 unsigned int index; 239 unsigned int axis_count; 240 unsigned int data_offset; 241 242 public: 243 hb_bytes_t var_data_bytes; 244 const TupleVariationHeader *current_tuple; 245 }; 246 get_tuple_iteratorOT::GlyphVariationData247 static bool get_tuple_iterator (hb_bytes_t var_data_bytes, unsigned axis_count, 248 hb_vector_t<unsigned int> &shared_indices /* OUT */, 249 tuple_iterator_t *iterator /* OUT */) 250 { 251 iterator->init (var_data_bytes, axis_count); 252 if (!iterator->get_shared_indices (shared_indices)) 253 return false; 254 return iterator->is_valid (); 255 } 256 has_shared_point_numbersOT::GlyphVariationData257 bool has_shared_point_numbers () const { return tupleVarCount.has_shared_point_numbers (); } 258 unpack_pointsOT::GlyphVariationData259 static bool unpack_points (const HBUINT8 *&p /* IN/OUT */, 260 hb_vector_t<unsigned int> &points /* OUT */, 261 const hb_bytes_t &bytes) 262 { 263 enum packed_point_flag_t 264 { 265 POINTS_ARE_WORDS = 0x80, 266 POINT_RUN_COUNT_MASK = 0x7F 267 }; 268 269 if (unlikely (!bytes.check_range (p))) return false; 270 271 uint16_t count = *p++; 272 if (count & POINTS_ARE_WORDS) 273 { 274 if (unlikely (!bytes.check_range (p))) return false; 275 count = ((count & POINT_RUN_COUNT_MASK) << 8) | *p++; 276 } 277 points.resize (count); 278 279 unsigned int n = 0; 280 uint16_t i = 0; 281 while (i < count) 282 { 283 if (unlikely (!bytes.check_range (p))) return false; 284 uint16_t j; 285 uint8_t control = *p++; 286 uint16_t run_count = (control & POINT_RUN_COUNT_MASK) + 1; 287 if (control & POINTS_ARE_WORDS) 288 { 289 for (j = 0; j < run_count && i < count; j++, i++) 290 { 291 if (unlikely (!bytes.check_range ((const HBUINT16 *) p))) 292 return false; 293 n += *(const HBUINT16 *)p; 294 points[i] = n; 295 p += HBUINT16::static_size; 296 } 297 } 298 else 299 { 300 for (j = 0; j < run_count && i < count; j++, i++) 301 { 302 if (unlikely (!bytes.check_range (p))) return false; 303 n += *p++; 304 points[i] = n; 305 } 306 } 307 if (j < run_count) return false; 308 } 309 return true; 310 } 311 unpack_deltasOT::GlyphVariationData312 static bool unpack_deltas (const HBUINT8 *&p /* IN/OUT */, 313 hb_vector_t<int> &deltas /* IN/OUT */, 314 const hb_bytes_t &bytes) 315 { 316 enum packed_delta_flag_t 317 { 318 DELTAS_ARE_ZERO = 0x80, 319 DELTAS_ARE_WORDS = 0x40, 320 DELTA_RUN_COUNT_MASK = 0x3F 321 }; 322 323 unsigned int i = 0; 324 unsigned int count = deltas.length; 325 while (i < count) 326 { 327 if (unlikely (!bytes.check_range (p))) return false; 328 uint8_t control = *p++; 329 unsigned int run_count = (control & DELTA_RUN_COUNT_MASK) + 1; 330 unsigned int j; 331 if (control & DELTAS_ARE_ZERO) 332 for (j = 0; j < run_count && i < count; j++, i++) 333 deltas[i] = 0; 334 else if (control & DELTAS_ARE_WORDS) 335 for (j = 0; j < run_count && i < count; j++, i++) 336 { 337 if (unlikely (!bytes.check_range ((const HBUINT16 *) p))) 338 return false; 339 deltas[i] = *(const HBINT16 *) p; 340 p += HBUINT16::static_size; 341 } 342 else 343 for (j = 0; j < run_count && i < count; j++, i++) 344 { 345 if (unlikely (!bytes.check_range (p))) 346 return false; 347 deltas[i] = *(const HBINT8 *) p++; 348 } 349 if (j < run_count) 350 return false; 351 } 352 return true; 353 } 354 has_dataOT::GlyphVariationData355 bool has_data () const { return tupleVarCount; } 356 357 protected: 358 struct TupleVarCount : HBUINT16 359 { has_shared_point_numbersOT::GlyphVariationData::TupleVarCount360 bool has_shared_point_numbers () const { return ((*this) & SharedPointNumbers); } get_countOT::GlyphVariationData::TupleVarCount361 unsigned int get_count () const { return (*this) & CountMask; } 362 363 protected: 364 enum Flags 365 { 366 SharedPointNumbers= 0x8000u, 367 CountMask = 0x0FFFu 368 }; 369 public: 370 DEFINE_SIZE_STATIC (2); 371 }; 372 373 TupleVarCount tupleVarCount; /* A packed field. The high 4 bits are flags, and the 374 * low 12 bits are the number of tuple variation tables 375 * for this glyph. The number of tuple variation tables 376 * can be any number between 1 and 4095. */ 377 Offset16To<HBUINT8> 378 data; /* Offset from the start of the GlyphVariationData table 379 * to the serialized data. */ 380 /* TupleVariationHeader tupleVariationHeaders[] *//* Array of tuple variation headers. */ 381 public: 382 DEFINE_SIZE_MIN (4); 383 }; 384 385 struct gvar 386 { 387 static constexpr hb_tag_t tableTag = HB_OT_TAG_gvar; 388 sanitize_shallowOT::gvar389 bool sanitize_shallow (hb_sanitize_context_t *c) const 390 { 391 TRACE_SANITIZE (this); 392 return_trace (c->check_struct (this) && (version.major == 1) && 393 (glyphCount == c->get_num_glyphs ()) && 394 sharedTuples.sanitize (c, this, axisCount * sharedTupleCount) && 395 (is_long_offset () ? 396 c->check_array (get_long_offset_array (), glyphCount+1) : 397 c->check_array (get_short_offset_array (), glyphCount+1)) && 398 c->check_array (((const HBUINT8*)&(this+dataZ)) + get_offset (0), 399 get_offset (glyphCount) - get_offset (0))); 400 } 401 402 /* GlyphVariationData not sanitized here; must be checked while accessing each glyph varation data */ sanitizeOT::gvar403 bool sanitize (hb_sanitize_context_t *c) const 404 { return sanitize_shallow (c); } 405 subsetOT::gvar406 bool subset (hb_subset_context_t *c) const 407 { 408 TRACE_SUBSET (this); 409 410 gvar *out = c->serializer->allocate_min<gvar> (); 411 if (unlikely (!out)) return_trace (false); 412 413 out->version.major = 1; 414 out->version.minor = 0; 415 out->axisCount = axisCount; 416 out->sharedTupleCount = sharedTupleCount; 417 418 unsigned int num_glyphs = c->plan->num_output_glyphs (); 419 out->glyphCount = num_glyphs; 420 421 unsigned int subset_data_size = 0; 422 for (hb_codepoint_t gid = 0; gid < num_glyphs; gid++) 423 { 424 hb_codepoint_t old_gid; 425 if (!c->plan->old_gid_for_new_gid (gid, &old_gid)) continue; 426 subset_data_size += get_glyph_var_data_bytes (c->source_blob, old_gid).length; 427 } 428 429 bool long_offset = subset_data_size & ~0xFFFFu; 430 out->flags = long_offset ? 1 : 0; 431 432 HBUINT8 *subset_offsets = c->serializer->allocate_size<HBUINT8> ((long_offset ? 4 : 2) * (num_glyphs + 1)); 433 if (!subset_offsets) return_trace (false); 434 435 /* shared tuples */ 436 if (!sharedTupleCount || !sharedTuples) 437 out->sharedTuples = 0; 438 else 439 { 440 unsigned int shared_tuple_size = F2DOT14::static_size * axisCount * sharedTupleCount; 441 F2DOT14 *tuples = c->serializer->allocate_size<F2DOT14> (shared_tuple_size); 442 if (!tuples) return_trace (false); 443 out->sharedTuples = (char *) tuples - (char *) out; 444 memcpy (tuples, this+sharedTuples, shared_tuple_size); 445 } 446 447 char *subset_data = c->serializer->allocate_size<char> (subset_data_size); 448 if (!subset_data) return_trace (false); 449 out->dataZ = subset_data - (char *) out; 450 451 unsigned int glyph_offset = 0; 452 for (hb_codepoint_t gid = 0; gid < num_glyphs; gid++) 453 { 454 hb_codepoint_t old_gid; 455 hb_bytes_t var_data_bytes = c->plan->old_gid_for_new_gid (gid, &old_gid) 456 ? get_glyph_var_data_bytes (c->source_blob, old_gid) 457 : hb_bytes_t (); 458 459 if (long_offset) 460 ((HBUINT32 *) subset_offsets)[gid] = glyph_offset; 461 else 462 ((HBUINT16 *) subset_offsets)[gid] = glyph_offset / 2; 463 464 if (var_data_bytes.length > 0) 465 memcpy (subset_data, var_data_bytes.arrayZ, var_data_bytes.length); 466 subset_data += var_data_bytes.length; 467 glyph_offset += var_data_bytes.length; 468 } 469 if (long_offset) 470 ((HBUINT32 *) subset_offsets)[num_glyphs] = glyph_offset; 471 else 472 ((HBUINT16 *) subset_offsets)[num_glyphs] = glyph_offset / 2; 473 474 return_trace (true); 475 } 476 477 protected: get_glyph_var_data_bytesOT::gvar478 const hb_bytes_t get_glyph_var_data_bytes (hb_blob_t *blob, hb_codepoint_t glyph) const 479 { 480 unsigned start_offset = get_offset (glyph); 481 unsigned length = get_offset (glyph+1) - start_offset; 482 hb_bytes_t var_data = blob->as_bytes ().sub_array (((unsigned) dataZ) + start_offset, length); 483 return likely (var_data.length >= GlyphVariationData::min_size) ? var_data : hb_bytes_t (); 484 } 485 is_long_offsetOT::gvar486 bool is_long_offset () const { return flags & 1; } 487 get_offsetOT::gvar488 unsigned get_offset (unsigned i) const 489 { return is_long_offset () ? get_long_offset_array ()[i] : get_short_offset_array ()[i] * 2; } 490 get_long_offset_arrayOT::gvar491 const HBUINT32 * get_long_offset_array () const { return (const HBUINT32 *) &offsetZ; } get_short_offset_arrayOT::gvar492 const HBUINT16 *get_short_offset_array () const { return (const HBUINT16 *) &offsetZ; } 493 494 public: 495 struct accelerator_t 496 { initOT::gvar::accelerator_t497 void init (hb_face_t *face) 498 { table = hb_sanitize_context_t ().reference_table<gvar> (face); } finiOT::gvar::accelerator_t499 void fini () { table.destroy (); } 500 501 private: getOT::gvar::accelerator_t::x_getter502 struct x_getter { static float get (const contour_point_t &p) { return p.x; } }; getOT::gvar::accelerator_t::y_getter503 struct y_getter { static float get (const contour_point_t &p) { return p.y; } }; 504 505 template <typename T> infer_deltaOT::gvar::accelerator_t506 static float infer_delta (const hb_array_t<contour_point_t> points, 507 const hb_array_t<contour_point_t> deltas, 508 unsigned int target, unsigned int prev, unsigned int next) 509 { 510 float target_val = T::get (points[target]); 511 float prev_val = T::get (points[prev]); 512 float next_val = T::get (points[next]); 513 float prev_delta = T::get (deltas[prev]); 514 float next_delta = T::get (deltas[next]); 515 516 if (prev_val == next_val) 517 return (prev_delta == next_delta) ? prev_delta : 0.f; 518 else if (target_val <= hb_min (prev_val, next_val)) 519 return (prev_val < next_val) ? prev_delta : next_delta; 520 else if (target_val >= hb_max (prev_val, next_val)) 521 return (prev_val > next_val) ? prev_delta : next_delta; 522 523 /* linear interpolation */ 524 float r = (target_val - prev_val) / (next_val - prev_val); 525 return (1.f - r) * prev_delta + r * next_delta; 526 } 527 next_indexOT::gvar::accelerator_t528 static unsigned int next_index (unsigned int i, unsigned int start, unsigned int end) 529 { return (i >= end) ? start : (i + 1); } 530 531 public: apply_deltas_to_pointsOT::gvar::accelerator_t532 bool apply_deltas_to_points (hb_codepoint_t glyph, hb_font_t *font, 533 const hb_array_t<contour_point_t> points) const 534 { 535 /* num_coords should exactly match gvar's axisCount due to how GlyphVariationData tuples are aligned */ 536 if (!font->num_coords || font->num_coords != table->axisCount) return true; 537 538 if (unlikely (glyph >= table->glyphCount)) return true; 539 540 hb_bytes_t var_data_bytes = table->get_glyph_var_data_bytes (table.get_blob (), glyph); 541 if (!var_data_bytes.as<GlyphVariationData> ()->has_data ()) return true; 542 hb_vector_t<unsigned int> shared_indices; 543 GlyphVariationData::tuple_iterator_t iterator; 544 if (!GlyphVariationData::get_tuple_iterator (var_data_bytes, table->axisCount, 545 shared_indices, &iterator)) 546 return true; /* so isn't applied at all */ 547 548 /* Save original points for inferred delta calculation */ 549 contour_point_vector_t orig_points; 550 orig_points.resize (points.length); 551 for (unsigned int i = 0; i < orig_points.length; i++) 552 orig_points[i] = points[i]; 553 554 contour_point_vector_t deltas; /* flag is used to indicate referenced point */ 555 deltas.resize (points.length); 556 557 hb_vector_t<unsigned> end_points; 558 for (unsigned i = 0; i < points.length; ++i) 559 if (points[i].is_end_point) 560 end_points.push (i); 561 562 int *coords = font->coords; 563 unsigned num_coords = font->num_coords; 564 hb_array_t<const F2DOT14> shared_tuples = (table+table->sharedTuples).as_array (table->sharedTupleCount * table->axisCount); 565 do 566 { 567 float scalar = iterator.current_tuple->calculate_scalar (coords, num_coords, shared_tuples); 568 if (scalar == 0.f) continue; 569 const HBUINT8 *p = iterator.get_serialized_data (); 570 unsigned int length = iterator.current_tuple->get_data_size (); 571 if (unlikely (!iterator.var_data_bytes.check_range (p, length))) 572 return false; 573 574 hb_bytes_t bytes ((const char *) p, length); 575 hb_vector_t<unsigned int> private_indices; 576 if (iterator.current_tuple->has_private_points () && 577 !GlyphVariationData::unpack_points (p, private_indices, bytes)) 578 return false; 579 const hb_array_t<unsigned int> &indices = private_indices.length ? private_indices : shared_indices; 580 581 bool apply_to_all = (indices.length == 0); 582 unsigned int num_deltas = apply_to_all ? points.length : indices.length; 583 hb_vector_t<int> x_deltas; 584 x_deltas.resize (num_deltas); 585 if (!GlyphVariationData::unpack_deltas (p, x_deltas, bytes)) 586 return false; 587 hb_vector_t<int> y_deltas; 588 y_deltas.resize (num_deltas); 589 if (!GlyphVariationData::unpack_deltas (p, y_deltas, bytes)) 590 return false; 591 592 for (unsigned int i = 0; i < deltas.length; i++) 593 deltas[i].init (); 594 for (unsigned int i = 0; i < num_deltas; i++) 595 { 596 unsigned int pt_index = apply_to_all ? i : indices[i]; 597 deltas[pt_index].flag = 1; /* this point is referenced, i.e., explicit deltas specified */ 598 deltas[pt_index].x += x_deltas[i] * scalar; 599 deltas[pt_index].y += y_deltas[i] * scalar; 600 } 601 602 /* infer deltas for unreferenced points */ 603 unsigned start_point = 0; 604 for (unsigned c = 0; c < end_points.length; c++) 605 { 606 unsigned end_point = end_points[c]; 607 608 /* Check the number of unreferenced points in a contour. If no unref points or no ref points, nothing to do. */ 609 unsigned unref_count = 0; 610 for (unsigned i = start_point; i <= end_point; i++) 611 if (!deltas[i].flag) unref_count++; 612 613 unsigned j = start_point; 614 if (unref_count == 0 || unref_count > end_point - start_point) 615 goto no_more_gaps; 616 617 for (;;) 618 { 619 /* Locate the next gap of unreferenced points between two referenced points prev and next. 620 * Note that a gap may wrap around at left (start_point) and/or at right (end_point). 621 */ 622 unsigned int prev, next, i; 623 for (;;) 624 { 625 i = j; 626 j = next_index (i, start_point, end_point); 627 if (deltas[i].flag && !deltas[j].flag) break; 628 } 629 prev = j = i; 630 for (;;) 631 { 632 i = j; 633 j = next_index (i, start_point, end_point); 634 if (!deltas[i].flag && deltas[j].flag) break; 635 } 636 next = j; 637 /* Infer deltas for all unref points in the gap between prev and next */ 638 i = prev; 639 for (;;) 640 { 641 i = next_index (i, start_point, end_point); 642 if (i == next) break; 643 deltas[i].x = infer_delta<x_getter> (orig_points.as_array (), deltas.as_array (), i, prev, next); 644 deltas[i].y = infer_delta<y_getter> (orig_points.as_array (), deltas.as_array (), i, prev, next); 645 if (--unref_count == 0) goto no_more_gaps; 646 } 647 } 648 no_more_gaps: 649 start_point = end_point + 1; 650 } 651 652 /* apply specified / inferred deltas to points */ 653 for (unsigned int i = 0; i < points.length; i++) 654 { 655 points[i].x += deltas[i].x; 656 points[i].y += deltas[i].y; 657 } 658 } while (iterator.move_to_next ()); 659 660 return true; 661 } 662 get_axis_countOT::gvar::accelerator_t663 unsigned int get_axis_count () const { return table->axisCount; } 664 665 private: 666 hb_blob_ptr_t<gvar> table; 667 }; 668 669 protected: 670 FixedVersion<>version; /* Version number of the glyph variations table 671 * Set to 0x00010000u. */ 672 HBUINT16 axisCount; /* The number of variation axes for this font. This must be 673 * the same number as axisCount in the 'fvar' table. */ 674 HBUINT16 sharedTupleCount; 675 /* The number of shared tuple records. Shared tuple records 676 * can be referenced within glyph variation data tables for 677 * multiple glyphs, as opposed to other tuple records stored 678 * directly within a glyph variation data table. */ 679 NNOffset32To<UnsizedArrayOf<F2DOT14>> 680 sharedTuples; /* Offset from the start of this table to the shared tuple records. 681 * Array of tuple records shared across all glyph variation data tables. */ 682 HBUINT16 glyphCount; /* The number of glyphs in this font. This must match the number of 683 * glyphs stored elsewhere in the font. */ 684 HBUINT16 flags; /* Bit-field that gives the format of the offset array that follows. 685 * If bit 0 is clear, the offsets are uint16; if bit 0 is set, the 686 * offsets are uint32. */ 687 Offset32To<GlyphVariationData> 688 dataZ; /* Offset from the start of this table to the array of 689 * GlyphVariationData tables. */ 690 UnsizedArrayOf<HBUINT8> 691 offsetZ; /* Offsets from the start of the GlyphVariationData array 692 * to each GlyphVariationData table. */ 693 public: 694 DEFINE_SIZE_MIN (20); 695 }; 696 697 struct gvar_accelerator_t : gvar::accelerator_t {}; 698 699 } /* namespace OT */ 700 701 #endif /* HB_OT_VAR_GVAR_TABLE_HH */ 702