1 /* 2 * Copyright © 2015 Google, Inc. 3 * Copyright © 2019 Adobe Inc. 4 * Copyright © 2019 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, Garret Rieger, Roderick Sheeter 27 * Adobe Author(s): Michiharu Ariza 28 */ 29 30 #ifndef HB_OT_GLYF_TABLE_HH 31 #define HB_OT_GLYF_TABLE_HH 32 33 #include "hb-open-type.hh" 34 #include "hb-ot-head-table.hh" 35 #include "hb-ot-hmtx-table.hh" 36 #include "hb-ot-var-gvar-table.hh" 37 38 #include <float.h> 39 40 namespace OT { 41 42 43 /* 44 * loca -- Index to Location 45 * https://docs.microsoft.com/en-us/typography/opentype/spec/loca 46 */ 47 #define HB_OT_TAG_loca HB_TAG('l','o','c','a') 48 49 50 struct loca 51 { 52 friend struct glyf; 53 54 static constexpr hb_tag_t tableTag = HB_OT_TAG_loca; 55 sanitizeOT::loca56 bool sanitize (hb_sanitize_context_t *c HB_UNUSED) const 57 { 58 TRACE_SANITIZE (this); 59 return_trace (true); 60 } 61 62 protected: 63 UnsizedArrayOf<HBUINT8> 64 dataZ; /* Location data. */ 65 public: 66 DEFINE_SIZE_MIN (0); /* In reality, this is UNBOUNDED() type; but since we always 67 * check the size externally, allow Null() object of it by 68 * defining it _MIN instead. */ 69 }; 70 71 72 /* 73 * glyf -- TrueType Glyph Data 74 * https://docs.microsoft.com/en-us/typography/opentype/spec/glyf 75 */ 76 #define HB_OT_TAG_glyf HB_TAG('g','l','y','f') 77 78 79 struct glyf 80 { 81 static constexpr hb_tag_t tableTag = HB_OT_TAG_glyf; 82 sanitizeOT::glyf83 bool sanitize (hb_sanitize_context_t *c HB_UNUSED) const 84 { 85 TRACE_SANITIZE (this); 86 /* Runtime checks as eager sanitizing each glyph is costy */ 87 return_trace (true); 88 } 89 90 template<typename Iterator, 91 hb_requires (hb_is_source_of (Iterator, unsigned int))> 92 static bool _add_loca_and_headOT::glyf93 _add_loca_and_head (hb_subset_plan_t * plan, Iterator padded_offsets) 94 { 95 unsigned max_offset = + padded_offsets | hb_reduce(hb_add, 0); 96 unsigned num_offsets = padded_offsets.len () + 1; 97 bool use_short_loca = max_offset < 0x1FFFF; 98 unsigned entry_size = use_short_loca ? 2 : 4; 99 char *loca_prime_data = (char *) calloc (entry_size, num_offsets); 100 101 if (unlikely (!loca_prime_data)) return false; 102 103 DEBUG_MSG (SUBSET, nullptr, "loca entry_size %d num_offsets %d " 104 "max_offset %d size %d", 105 entry_size, num_offsets, max_offset, entry_size * num_offsets); 106 107 if (use_short_loca) 108 _write_loca (padded_offsets, 1, hb_array ((HBUINT16*) loca_prime_data, num_offsets)); 109 else 110 _write_loca (padded_offsets, 0, hb_array ((HBUINT32*) loca_prime_data, num_offsets)); 111 112 hb_blob_t * loca_blob = hb_blob_create (loca_prime_data, 113 entry_size * num_offsets, 114 HB_MEMORY_MODE_WRITABLE, 115 loca_prime_data, 116 free); 117 118 bool result = plan->add_table (HB_OT_TAG_loca, loca_blob) 119 && _add_head_and_set_loca_version (plan, use_short_loca); 120 121 hb_blob_destroy (loca_blob); 122 return result; 123 } 124 125 template<typename IteratorIn, typename IteratorOut, 126 hb_requires (hb_is_source_of (IteratorIn, unsigned int)), 127 hb_requires (hb_is_sink_of (IteratorOut, unsigned))> 128 static void _write_locaOT::glyf129 _write_loca (IteratorIn it, unsigned right_shift, IteratorOut dest) 130 { 131 unsigned int offset = 0; 132 dest << 0; 133 + it 134 | hb_map ([=, &offset] (unsigned int padded_size) 135 { 136 offset += padded_size; 137 DEBUG_MSG (SUBSET, nullptr, "loca entry offset %d", offset); 138 return offset >> right_shift; 139 }) 140 | hb_sink (dest) 141 ; 142 } 143 144 /* requires source of SubsetGlyph complains the identifier isn't declared */ 145 template <typename Iterator> serializeOT::glyf146 bool serialize (hb_serialize_context_t *c, 147 Iterator it, 148 const hb_subset_plan_t *plan) 149 { 150 TRACE_SERIALIZE (this); 151 for (const auto &_ : it) _.serialize (c, plan); 152 return_trace (true); 153 } 154 155 /* Byte region(s) per glyph to output 156 unpadded, hints removed if so requested 157 If we fail to process a glyph we produce an empty (0-length) glyph */ subsetOT::glyf158 bool subset (hb_subset_context_t *c) const 159 { 160 TRACE_SUBSET (this); 161 162 glyf *glyf_prime = c->serializer->start_embed <glyf> (); 163 if (unlikely (!c->serializer->check_success (glyf_prime))) return_trace (false); 164 165 hb_vector_t<SubsetGlyph> glyphs; 166 _populate_subset_glyphs (c->plan, &glyphs); 167 168 glyf_prime->serialize (c->serializer, hb_iter (glyphs), c->plan); 169 170 auto padded_offsets = 171 + hb_iter (glyphs) 172 | hb_map (&SubsetGlyph::padded_size) 173 ; 174 175 if (c->serializer->in_error ()) return_trace (false); 176 return_trace (c->serializer->check_success (_add_loca_and_head (c->plan, 177 padded_offsets))); 178 } 179 180 template <typename SubsetGlyph> 181 void _populate_subset_glyphsOT::glyf182 _populate_subset_glyphs (const hb_subset_plan_t *plan, 183 hb_vector_t<SubsetGlyph> *glyphs /* OUT */) const 184 { 185 OT::glyf::accelerator_t glyf; 186 glyf.init (plan->source); 187 188 + hb_range (plan->num_output_glyphs ()) 189 | hb_map ([&] (hb_codepoint_t new_gid) 190 { 191 SubsetGlyph subset_glyph = {0}; 192 subset_glyph.new_gid = new_gid; 193 194 /* should never fail: all old gids should be mapped */ 195 if (!plan->old_gid_for_new_gid (new_gid, &subset_glyph.old_gid)) 196 return subset_glyph; 197 198 subset_glyph.source_glyph = glyf.glyph_for_gid (subset_glyph.old_gid, true); 199 if (plan->drop_hints) subset_glyph.drop_hints_bytes (); 200 else subset_glyph.dest_start = subset_glyph.source_glyph.get_bytes (); 201 202 return subset_glyph; 203 }) 204 | hb_sink (glyphs) 205 ; 206 207 glyf.fini (); 208 } 209 210 static bool _add_head_and_set_loca_versionOT::glyf211 _add_head_and_set_loca_version (hb_subset_plan_t *plan, bool use_short_loca) 212 { 213 hb_blob_t *head_blob = hb_sanitize_context_t ().reference_table<head> (plan->source); 214 hb_blob_t *head_prime_blob = hb_blob_copy_writable_or_fail (head_blob); 215 hb_blob_destroy (head_blob); 216 217 if (unlikely (!head_prime_blob)) 218 return false; 219 220 head *head_prime = (head *) hb_blob_get_data_writable (head_prime_blob, nullptr); 221 head_prime->indexToLocFormat = use_short_loca ? 0 : 1; 222 bool success = plan->add_table (HB_OT_TAG_head, head_prime_blob); 223 224 hb_blob_destroy (head_prime_blob); 225 return success; 226 } 227 228 struct CompositeGlyphChain 229 { 230 enum composite_glyph_flag_t 231 { 232 ARG_1_AND_2_ARE_WORDS = 0x0001, 233 ARGS_ARE_XY_VALUES = 0x0002, 234 ROUND_XY_TO_GRID = 0x0004, 235 WE_HAVE_A_SCALE = 0x0008, 236 MORE_COMPONENTS = 0x0020, 237 WE_HAVE_AN_X_AND_Y_SCALE = 0x0040, 238 WE_HAVE_A_TWO_BY_TWO = 0x0080, 239 WE_HAVE_INSTRUCTIONS = 0x0100, 240 USE_MY_METRICS = 0x0200, 241 OVERLAP_COMPOUND = 0x0400, 242 SCALED_COMPONENT_OFFSET = 0x0800, 243 UNSCALED_COMPONENT_OFFSET = 0x1000 244 }; 245 get_sizeOT::glyf::CompositeGlyphChain246 unsigned int get_size () const 247 { 248 unsigned int size = min_size; 249 /* arg1 and 2 are int16 */ 250 if (flags & ARG_1_AND_2_ARE_WORDS) size += 4; 251 /* arg1 and 2 are int8 */ 252 else size += 2; 253 254 /* One x 16 bit (scale) */ 255 if (flags & WE_HAVE_A_SCALE) size += 2; 256 /* Two x 16 bit (xscale, yscale) */ 257 else if (flags & WE_HAVE_AN_X_AND_Y_SCALE) size += 4; 258 /* Four x 16 bit (xscale, scale01, scale10, yscale) */ 259 else if (flags & WE_HAVE_A_TWO_BY_TWO) size += 8; 260 261 return size; 262 } 263 is_use_my_metricsOT::glyf::CompositeGlyphChain264 bool is_use_my_metrics () const { return flags & USE_MY_METRICS; } is_anchoredOT::glyf::CompositeGlyphChain265 bool is_anchored () const { return !(flags & ARGS_ARE_XY_VALUES); } get_anchor_pointsOT::glyf::CompositeGlyphChain266 void get_anchor_points (unsigned int &point1, unsigned int &point2) const 267 { 268 const HBUINT8 *p = &StructAfter<const HBUINT8> (glyphIndex); 269 if (flags & ARG_1_AND_2_ARE_WORDS) 270 { 271 point1 = ((const HBUINT16 *) p)[0]; 272 point2 = ((const HBUINT16 *) p)[1]; 273 } 274 else 275 { 276 point1 = p[0]; 277 point2 = p[1]; 278 } 279 } 280 transform_pointsOT::glyf::CompositeGlyphChain281 void transform_points (contour_point_vector_t &points) const 282 { 283 float matrix[4]; 284 contour_point_t trans; 285 if (get_transformation (matrix, trans)) 286 { 287 if (scaled_offsets ()) 288 { 289 points.translate (trans); 290 points.transform (matrix); 291 } 292 else 293 { 294 points.transform (matrix); 295 points.translate (trans); 296 } 297 } 298 } 299 300 protected: scaled_offsetsOT::glyf::CompositeGlyphChain301 bool scaled_offsets () const 302 { return (flags & (SCALED_COMPONENT_OFFSET | UNSCALED_COMPONENT_OFFSET)) == SCALED_COMPONENT_OFFSET; } 303 get_transformationOT::glyf::CompositeGlyphChain304 bool get_transformation (float (&matrix)[4], contour_point_t &trans) const 305 { 306 matrix[0] = matrix[3] = 1.f; 307 matrix[1] = matrix[2] = 0.f; 308 309 int tx, ty; 310 const HBINT8 *p = &StructAfter<const HBINT8> (glyphIndex); 311 if (flags & ARG_1_AND_2_ARE_WORDS) 312 { 313 tx = *(const HBINT16 *) p; 314 p += HBINT16::static_size; 315 ty = *(const HBINT16 *) p; 316 p += HBINT16::static_size; 317 } 318 else 319 { 320 tx = *p++; 321 ty = *p++; 322 } 323 if (is_anchored ()) tx = ty = 0; 324 325 trans.init ((float) tx, (float) ty); 326 327 { 328 const F2DOT14 *points = (const F2DOT14 *) p; 329 if (flags & WE_HAVE_A_SCALE) 330 { 331 matrix[0] = matrix[3] = points[0].to_float (); 332 return true; 333 } 334 else if (flags & WE_HAVE_AN_X_AND_Y_SCALE) 335 { 336 matrix[0] = points[0].to_float (); 337 matrix[3] = points[1].to_float (); 338 return true; 339 } 340 else if (flags & WE_HAVE_A_TWO_BY_TWO) 341 { 342 matrix[0] = points[0].to_float (); 343 matrix[1] = points[1].to_float (); 344 matrix[2] = points[2].to_float (); 345 matrix[3] = points[3].to_float (); 346 return true; 347 } 348 } 349 return tx || ty; 350 } 351 352 public: 353 HBUINT16 flags; 354 HBGlyphID glyphIndex; 355 public: 356 DEFINE_SIZE_MIN (4); 357 }; 358 359 struct composite_iter_t : hb_iter_with_fallback_t<composite_iter_t, const CompositeGlyphChain &> 360 { 361 typedef const CompositeGlyphChain *__item_t__; composite_iter_tOT::glyf::composite_iter_t362 composite_iter_t (hb_bytes_t glyph_, __item_t__ current_) : 363 glyph (glyph_), current (current_) 364 { if (!in_range (current)) current = nullptr; } composite_iter_tOT::glyf::composite_iter_t365 composite_iter_t () : glyph (hb_bytes_t ()), current (nullptr) {} 366 __item__OT::glyf::composite_iter_t367 const CompositeGlyphChain &__item__ () const { return *current; } __more__OT::glyf::composite_iter_t368 bool __more__ () const { return current; } __next__OT::glyf::composite_iter_t369 void __next__ () 370 { 371 if (!(current->flags & CompositeGlyphChain::MORE_COMPONENTS)) { current = nullptr; return; } 372 373 const CompositeGlyphChain *possible = &StructAfter<CompositeGlyphChain, 374 CompositeGlyphChain> (*current); 375 if (!in_range (possible)) { current = nullptr; return; } 376 current = possible; 377 } operator !=OT::glyf::composite_iter_t378 bool operator != (const composite_iter_t& o) const 379 { return glyph != o.glyph || current != o.current; } 380 in_rangeOT::glyf::composite_iter_t381 bool in_range (const CompositeGlyphChain *composite) const 382 { 383 return glyph.in_range (composite, CompositeGlyphChain::min_size) 384 && glyph.in_range (composite, composite->get_size ()); 385 } 386 387 private: 388 hb_bytes_t glyph; 389 __item_t__ current; 390 }; 391 392 struct Glyph 393 { 394 private: 395 struct GlyphHeader 396 { has_dataOT::glyf::Glyph::GlyphHeader397 bool has_data () const { return numberOfContours; } 398 get_extentsOT::glyf::Glyph::GlyphHeader399 bool get_extents (hb_font_t *font, hb_codepoint_t gid, hb_glyph_extents_t *extents) const 400 { 401 /* Undocumented rasterizer behavior: shift glyph to the left by (lsb - xMin), i.e., xMin = lsb */ 402 /* extents->x_bearing = hb_min (glyph_header.xMin, glyph_header.xMax); */ 403 extents->x_bearing = font->em_scale_x (font->face->table.hmtx->get_side_bearing (gid)); 404 extents->y_bearing = font->em_scale_y (hb_max (yMin, yMax)); 405 extents->width = font->em_scale_x (hb_max (xMin, xMax) - hb_min (xMin, xMax)); 406 extents->height = font->em_scale_y (hb_min (yMin, yMax) - hb_max (yMin, yMax)); 407 408 return true; 409 } 410 411 HBINT16 numberOfContours; 412 /* If the number of contours is 413 * greater than or equal to zero, 414 * this is a simple glyph; if negative, 415 * this is a composite glyph. */ 416 FWORD xMin; /* Minimum x for coordinate data. */ 417 FWORD yMin; /* Minimum y for coordinate data. */ 418 FWORD xMax; /* Maximum x for coordinate data. */ 419 FWORD yMax; /* Maximum y for coordinate data. */ 420 public: 421 DEFINE_SIZE_STATIC (10); 422 }; 423 424 struct SimpleGlyph 425 { 426 const GlyphHeader &header; 427 hb_bytes_t bytes; SimpleGlyphOT::glyf::Glyph::SimpleGlyph428 SimpleGlyph (const GlyphHeader &header_, hb_bytes_t bytes_) : 429 header (header_), bytes (bytes_) {} 430 instruction_len_offsetOT::glyf::Glyph::SimpleGlyph431 unsigned int instruction_len_offset () const 432 { return GlyphHeader::static_size + 2 * header.numberOfContours; } 433 lengthOT::glyf::Glyph::SimpleGlyph434 unsigned int length (unsigned int instruction_len) const 435 { return instruction_len_offset () + 2 + instruction_len; } 436 instructions_lengthOT::glyf::Glyph::SimpleGlyph437 unsigned int instructions_length () const 438 { 439 unsigned int instruction_length_offset = instruction_len_offset (); 440 if (unlikely (instruction_length_offset + 2 > bytes.length)) return 0; 441 442 const HBUINT16 &instructionLength = StructAtOffset<HBUINT16> (&bytes, instruction_length_offset); 443 /* Out of bounds of the current glyph */ 444 if (unlikely (length (instructionLength) > bytes.length)) return 0; 445 return instructionLength; 446 } 447 448 enum simple_glyph_flag_t 449 { 450 FLAG_ON_CURVE = 0x01, 451 FLAG_X_SHORT = 0x02, 452 FLAG_Y_SHORT = 0x04, 453 FLAG_REPEAT = 0x08, 454 FLAG_X_SAME = 0x10, 455 FLAG_Y_SAME = 0x20, 456 FLAG_RESERVED1 = 0x40, 457 FLAG_RESERVED2 = 0x80 458 }; 459 trim_paddingOT::glyf::Glyph::SimpleGlyph460 const Glyph trim_padding () const 461 { 462 /* based on FontTools _g_l_y_f.py::trim */ 463 const char *glyph = bytes.arrayZ; 464 const char *glyph_end = glyph + bytes.length; 465 /* simple glyph w/contours, possibly trimmable */ 466 glyph += instruction_len_offset (); 467 468 if (unlikely (glyph + 2 >= glyph_end)) return Glyph (); 469 unsigned int num_coordinates = StructAtOffset<HBUINT16> (glyph - 2, 0) + 1; 470 unsigned int num_instructions = StructAtOffset<HBUINT16> (glyph, 0); 471 472 glyph += 2 + num_instructions; 473 if (unlikely (glyph + 2 >= glyph_end)) return Glyph (); 474 475 unsigned int coord_bytes = 0; 476 unsigned int coords_with_flags = 0; 477 while (glyph < glyph_end) 478 { 479 uint8_t flag = *glyph; 480 glyph++; 481 482 unsigned int repeat = 1; 483 if (flag & FLAG_REPEAT) 484 { 485 if (unlikely (glyph >= glyph_end)) return Glyph (); 486 repeat = *glyph + 1; 487 glyph++; 488 } 489 490 unsigned int xBytes, yBytes; 491 xBytes = yBytes = 0; 492 if (flag & FLAG_X_SHORT) xBytes = 1; 493 else if ((flag & FLAG_X_SAME) == 0) xBytes = 2; 494 495 if (flag & FLAG_Y_SHORT) yBytes = 1; 496 else if ((flag & FLAG_Y_SAME) == 0) yBytes = 2; 497 498 coord_bytes += (xBytes + yBytes) * repeat; 499 coords_with_flags += repeat; 500 if (coords_with_flags >= num_coordinates) break; 501 } 502 503 if (unlikely (coords_with_flags != num_coordinates)) return Glyph (); 504 return Glyph (bytes.sub_array (0, bytes.length + coord_bytes - (glyph_end - glyph))); 505 } 506 507 /* zero instruction length */ drop_hintsOT::glyf::Glyph::SimpleGlyph508 void drop_hints () 509 { 510 GlyphHeader &glyph_header = const_cast<GlyphHeader &> (header); 511 (HBUINT16 &) StructAtOffset<HBUINT16> (&glyph_header, instruction_len_offset ()) = 0; 512 } 513 drop_hints_bytesOT::glyf::Glyph::SimpleGlyph514 void drop_hints_bytes (hb_bytes_t &dest_start, hb_bytes_t &dest_end) const 515 { 516 unsigned int instructions_len = instructions_length (); 517 unsigned int glyph_length = length (instructions_len); 518 dest_start = bytes.sub_array (0, glyph_length - instructions_len); 519 dest_end = bytes.sub_array (glyph_length, bytes.length - glyph_length); 520 } 521 522 struct x_setter_t 523 { setOT::glyf::Glyph::SimpleGlyph::x_setter_t524 void set (contour_point_t &point, float v) const { point.x = v; } is_shortOT::glyf::Glyph::SimpleGlyph::x_setter_t525 bool is_short (uint8_t flag) const { return flag & FLAG_X_SHORT; } is_sameOT::glyf::Glyph::SimpleGlyph::x_setter_t526 bool is_same (uint8_t flag) const { return flag & FLAG_X_SAME; } 527 }; 528 529 struct y_setter_t 530 { setOT::glyf::Glyph::SimpleGlyph::y_setter_t531 void set (contour_point_t &point, float v) const { point.y = v; } is_shortOT::glyf::Glyph::SimpleGlyph::y_setter_t532 bool is_short (uint8_t flag) const { return flag & FLAG_Y_SHORT; } is_sameOT::glyf::Glyph::SimpleGlyph::y_setter_t533 bool is_same (uint8_t flag) const { return flag & FLAG_Y_SAME; } 534 }; 535 536 template <typename T> read_pointsOT::glyf::Glyph::SimpleGlyph537 static bool read_points (const HBUINT8 *&p /* IN/OUT */, 538 contour_point_vector_t &points_ /* IN/OUT */, 539 const hb_bytes_t &bytes) 540 { 541 T coord_setter; 542 float v = 0; 543 for (unsigned int i = 0; i < points_.length - PHANTOM_COUNT; i++) 544 { 545 uint8_t flag = points_[i].flag; 546 if (coord_setter.is_short (flag)) 547 { 548 if (unlikely (!bytes.in_range (p))) return false; 549 if (coord_setter.is_same (flag)) 550 v += *p++; 551 else 552 v -= *p++; 553 } 554 else 555 { 556 if (!coord_setter.is_same (flag)) 557 { 558 if (unlikely (!bytes.in_range ((const HBUINT16 *) p))) return false; 559 v += *(const HBINT16 *) p; 560 p += HBINT16::static_size; 561 } 562 } 563 coord_setter.set (points_[i], v); 564 } 565 return true; 566 } 567 get_contour_pointsOT::glyf::Glyph::SimpleGlyph568 bool get_contour_points (contour_point_vector_t &points_ /* OUT */, 569 hb_vector_t<unsigned int> &end_points_ /* OUT */, 570 const bool phantom_only=false) const 571 { 572 const HBUINT16 *endPtsOfContours = &StructAfter<HBUINT16> (header); 573 int num_contours = header.numberOfContours; 574 if (unlikely (!bytes.in_range (&endPtsOfContours[num_contours + 1]))) return false; 575 unsigned int num_points = endPtsOfContours[num_contours - 1] + 1; 576 577 points_.resize (num_points + PHANTOM_COUNT); 578 for (unsigned int i = 0; i < points_.length; i++) points_[i].init (); 579 if (phantom_only) return true; 580 581 /* Read simple glyph points if !phantom_only */ 582 end_points_.resize (num_contours); 583 584 for (int i = 0; i < num_contours; i++) 585 end_points_[i] = endPtsOfContours[i]; 586 587 /* Skip instructions */ 588 const HBUINT8 *p = &StructAtOffset<HBUINT8> (&endPtsOfContours[num_contours + 1], 589 endPtsOfContours[num_contours]); 590 591 /* Read flags */ 592 for (unsigned int i = 0; i < num_points; i++) 593 { 594 if (unlikely (!bytes.in_range (p))) return false; 595 uint8_t flag = *p++; 596 points_[i].flag = flag; 597 if (flag & FLAG_REPEAT) 598 { 599 if (unlikely (!bytes.in_range (p))) return false; 600 unsigned int repeat_count = *p++; 601 while ((repeat_count-- > 0) && (++i < num_points)) 602 points_[i].flag = flag; 603 } 604 } 605 606 /* Read x & y coordinates */ 607 return (read_points<x_setter_t> (p, points_, bytes) && 608 read_points<y_setter_t> (p, points_, bytes)); 609 } 610 }; 611 612 struct CompositeGlyph 613 { 614 const GlyphHeader &header; 615 hb_bytes_t bytes; CompositeGlyphOT::glyf::Glyph::CompositeGlyph616 CompositeGlyph (const GlyphHeader &header_, hb_bytes_t bytes_) : 617 header (header_), bytes (bytes_) {} 618 get_iteratorOT::glyf::Glyph::CompositeGlyph619 composite_iter_t get_iterator () const 620 { return composite_iter_t (bytes, &StructAfter<CompositeGlyphChain, GlyphHeader> (header)); } 621 instructions_lengthOT::glyf::Glyph::CompositeGlyph622 unsigned int instructions_length (hb_bytes_t bytes) const 623 { 624 unsigned int start = bytes.length; 625 unsigned int end = bytes.length; 626 const CompositeGlyphChain *last = nullptr; 627 for (auto &item : get_iterator ()) 628 last = &item; 629 if (unlikely (!last)) return 0; 630 631 if ((uint16_t) last->flags & CompositeGlyphChain::WE_HAVE_INSTRUCTIONS) 632 start = (char *) last - &bytes + last->get_size (); 633 if (unlikely (start > end)) return 0; 634 return end - start; 635 } 636 637 /* Trimming for composites not implemented. 638 * If removing hints it falls out of that. */ trim_paddingOT::glyf::Glyph::CompositeGlyph639 const Glyph trim_padding () const { return Glyph (bytes); } 640 641 /* remove WE_HAVE_INSTRUCTIONS flag from composite glyph */ drop_hintsOT::glyf::Glyph::CompositeGlyph642 void drop_hints () 643 { 644 for (const auto &_ : get_iterator ()) 645 *const_cast<OT::HBUINT16 *> (&_.flags) = (uint16_t) _.flags & ~OT::glyf::CompositeGlyphChain::WE_HAVE_INSTRUCTIONS; 646 } 647 648 /* Chop instructions off the end */ drop_hints_bytesOT::glyf::Glyph::CompositeGlyph649 void drop_hints_bytes (hb_bytes_t &dest_start) const 650 { dest_start = bytes.sub_array (0, bytes.length - instructions_length (bytes)); } 651 get_contour_pointsOT::glyf::Glyph::CompositeGlyph652 bool get_contour_points (contour_point_vector_t &points_ /* OUT */, 653 hb_vector_t<unsigned int> &end_points_ /* OUT */, 654 const bool phantom_only=false) const 655 { 656 /* add one pseudo point for each component in composite glyph */ 657 unsigned int num_points = hb_len (get_iterator ()); 658 points_.resize (num_points + PHANTOM_COUNT); 659 for (unsigned int i = 0; i < points_.length; i++) points_[i].init (); 660 return true; 661 } 662 }; 663 664 enum glyph_type_t { EMPTY, SIMPLE, COMPOSITE }; 665 666 enum phantom_point_index_t 667 { 668 PHANTOM_LEFT = 0, 669 PHANTOM_RIGHT = 1, 670 PHANTOM_TOP = 2, 671 PHANTOM_BOTTOM = 3, 672 PHANTOM_COUNT = 4 673 }; 674 675 public: get_composite_iteratorOT::glyf::Glyph676 composite_iter_t get_composite_iterator () const 677 { 678 if (type != COMPOSITE) return composite_iter_t (); 679 return CompositeGlyph (*header, bytes).get_iterator (); 680 } 681 trim_paddingOT::glyf::Glyph682 const Glyph trim_padding () const 683 { 684 switch (type) { 685 case COMPOSITE: return CompositeGlyph (*header, bytes).trim_padding (); 686 case SIMPLE: return SimpleGlyph (*header, bytes).trim_padding (); 687 default: return bytes; 688 } 689 } 690 drop_hintsOT::glyf::Glyph691 void drop_hints () 692 { 693 switch (type) { 694 case COMPOSITE: CompositeGlyph (*header, bytes).drop_hints (); return; 695 case SIMPLE: SimpleGlyph (*header, bytes).drop_hints (); return; 696 default: return; 697 } 698 } 699 drop_hints_bytesOT::glyf::Glyph700 void drop_hints_bytes (hb_bytes_t &dest_start, hb_bytes_t &dest_end) const 701 { 702 switch (type) { 703 case COMPOSITE: CompositeGlyph (*header, bytes).drop_hints_bytes (dest_start); return; 704 case SIMPLE: SimpleGlyph (*header, bytes).drop_hints_bytes (dest_start, dest_end); return; 705 default: return; 706 } 707 } 708 709 /* for a simple glyph, return contour end points, flags, along with coordinate points 710 * for a composite glyph, return pseudo component points 711 * in both cases points trailed with four phantom points 712 */ get_contour_pointsOT::glyf::Glyph713 bool get_contour_points (contour_point_vector_t &points_ /* OUT */, 714 hb_vector_t<unsigned int> &end_points_ /* OUT */, 715 const bool phantom_only=false) const 716 { 717 switch (type) { 718 case COMPOSITE: return CompositeGlyph (*header, bytes).get_contour_points (points_, end_points_, phantom_only); 719 case SIMPLE: return SimpleGlyph (*header, bytes).get_contour_points (points_, end_points_, phantom_only); 720 default: 721 /* empty glyph */ 722 points_.resize (PHANTOM_COUNT); 723 for (unsigned int i = 0; i < points_.length; i++) points_[i].init (); 724 return true; 725 } 726 } 727 is_simple_glyphOT::glyf::Glyph728 bool is_simple_glyph () const { return type == SIMPLE; } is_composite_glyphOT::glyf::Glyph729 bool is_composite_glyph () const { return type == COMPOSITE; } 730 get_extentsOT::glyf::Glyph731 bool get_extents (hb_font_t *font, hb_codepoint_t gid, hb_glyph_extents_t *extents) const 732 { 733 if (type == EMPTY) return true; /* Empty glyph; zero extents. */ 734 return header->get_extents (font, gid, extents); 735 } 736 get_bytesOT::glyf::Glyph737 hb_bytes_t get_bytes () const { return bytes; } get_headerOT::glyf::Glyph738 const GlyphHeader &get_header () const { return *header; } 739 GlyphOT::glyf::Glyph740 Glyph (hb_bytes_t bytes_ = hb_bytes_t ()) : 741 bytes (bytes_), header (bytes.as<GlyphHeader> ()) 742 { 743 int num_contours = header->numberOfContours; 744 if (unlikely (num_contours == 0)) type = EMPTY; 745 else if (num_contours > 0) type = SIMPLE; 746 else type = COMPOSITE; /* negative numbers */ 747 } 748 749 protected: 750 hb_bytes_t bytes; 751 const GlyphHeader *header; 752 unsigned type; 753 }; 754 755 struct accelerator_t 756 { initOT::glyf::accelerator_t757 void init (hb_face_t *face_) 758 { 759 short_offset = false; 760 num_glyphs = 0; 761 loca_table = nullptr; 762 glyf_table = nullptr; 763 face = face_; 764 const OT::head &head = *face->table.head; 765 if (head.indexToLocFormat > 1 || head.glyphDataFormat > 0) 766 /* Unknown format. Leave num_glyphs=0, that takes care of disabling us. */ 767 return; 768 short_offset = 0 == head.indexToLocFormat; 769 770 loca_table = hb_sanitize_context_t ().reference_table<loca> (face); 771 glyf_table = hb_sanitize_context_t ().reference_table<glyf> (face); 772 773 num_glyphs = hb_max (1u, loca_table.get_length () / (short_offset ? 2 : 4)) - 1; 774 } 775 finiOT::glyf::accelerator_t776 void fini () 777 { 778 loca_table.destroy (); 779 glyf_table.destroy (); 780 } 781 782 enum phantom_point_index_t 783 { 784 PHANTOM_LEFT = 0, 785 PHANTOM_RIGHT = 1, 786 PHANTOM_TOP = 2, 787 PHANTOM_BOTTOM = 3, 788 PHANTOM_COUNT = 4 789 }; 790 791 protected: 792 init_phantom_pointsOT::glyf::accelerator_t793 void init_phantom_points (hb_codepoint_t gid, hb_array_t<contour_point_t> &phantoms /* IN/OUT */) const 794 { 795 const Glyph &glyph = glyph_for_gid (gid); 796 int h_delta = (int) glyph.get_header ().xMin - face->table.hmtx->get_side_bearing (gid); 797 int v_orig = (int) glyph.get_header ().yMax + face->table.vmtx->get_side_bearing (gid); 798 unsigned int h_adv = face->table.hmtx->get_advance (gid); 799 unsigned int v_adv = face->table.vmtx->get_advance (gid); 800 801 phantoms[PHANTOM_LEFT].x = h_delta; 802 phantoms[PHANTOM_RIGHT].x = h_adv + h_delta; 803 phantoms[PHANTOM_TOP].y = v_orig; 804 phantoms[PHANTOM_BOTTOM].y = v_orig - (int) v_adv; 805 } 806 807 struct contour_bounds_t 808 { contour_bounds_tOT::glyf::accelerator_t::contour_bounds_t809 contour_bounds_t () { min_x = min_y = FLT_MAX; max_x = max_y = -FLT_MAX; } 810 addOT::glyf::accelerator_t::contour_bounds_t811 void add (const contour_point_t &p) 812 { 813 min_x = hb_min (min_x, p.x); 814 min_y = hb_min (min_y, p.y); 815 max_x = hb_max (max_x, p.x); 816 max_y = hb_max (max_y, p.y); 817 } 818 emptyOT::glyf::accelerator_t::contour_bounds_t819 bool empty () const { return (min_x >= max_x) || (min_y >= max_y); } 820 get_extentsOT::glyf::accelerator_t::contour_bounds_t821 void get_extents (hb_font_t *font, hb_glyph_extents_t *extents) 822 { 823 if (unlikely (empty ())) 824 { 825 extents->width = 0; 826 extents->x_bearing = 0; 827 extents->height = 0; 828 extents->y_bearing = 0; 829 return; 830 } 831 extents->x_bearing = font->em_scalef_x (min_x); 832 extents->width = font->em_scalef_x (max_x - min_x); 833 extents->y_bearing = font->em_scalef_y (max_y); 834 extents->height = font->em_scalef_y (min_y - max_y); 835 } 836 837 protected: 838 float min_x, min_y, max_x, max_y; 839 }; 840 841 #ifndef HB_NO_VAR 842 /* Note: Recursively calls itself. 843 * all_points includes phantom points 844 */ get_points_varOT::glyf::accelerator_t845 bool get_points_var (hb_codepoint_t gid, 846 const int *coords, unsigned int coord_count, 847 contour_point_vector_t &all_points /* OUT */, 848 unsigned int depth = 0) const 849 { 850 if (unlikely (depth++ > HB_MAX_NESTING_LEVEL)) return false; 851 contour_point_vector_t points; 852 hb_vector_t<unsigned int> end_points; 853 const Glyph &glyph = glyph_for_gid (gid); 854 if (unlikely (!glyph.get_contour_points (points, end_points))) return false; 855 hb_array_t<contour_point_t> phantoms = points.sub_array (points.length - PHANTOM_COUNT, PHANTOM_COUNT); 856 init_phantom_points (gid, phantoms); 857 if (unlikely (!face->table.gvar->apply_deltas_to_points (gid, coords, coord_count, points.as_array (), end_points.as_array ()))) return false; 858 859 unsigned int comp_index = 0; 860 if (glyph.is_simple_glyph ()) 861 all_points.extend (points.as_array ()); 862 else if (glyph.is_composite_glyph ()) 863 { 864 for (auto &item : glyph.get_composite_iterator ()) 865 { 866 contour_point_vector_t comp_points; 867 if (unlikely (!get_points_var (item.glyphIndex, coords, coord_count, 868 comp_points, depth)) 869 || comp_points.length < PHANTOM_COUNT) 870 return false; 871 872 /* Copy phantom points from component if USE_MY_METRICS flag set */ 873 if (item.is_use_my_metrics ()) 874 for (unsigned int i = 0; i < PHANTOM_COUNT; i++) 875 phantoms[i] = comp_points[comp_points.length - PHANTOM_COUNT + i]; 876 877 /* Apply component transformation & translation */ 878 item.transform_points (comp_points); 879 880 /* Apply translatation from gvar */ 881 comp_points.translate (points[comp_index]); 882 883 if (item.is_anchored ()) 884 { 885 unsigned int p1, p2; 886 item.get_anchor_points (p1, p2); 887 if (likely (p1 < all_points.length && p2 < comp_points.length)) 888 { 889 contour_point_t delta; 890 delta.init (all_points[p1].x - comp_points[p2].x, 891 all_points[p1].y - comp_points[p2].y); 892 893 comp_points.translate (delta); 894 } 895 } 896 897 all_points.extend (comp_points.sub_array (0, comp_points.length - PHANTOM_COUNT)); 898 899 comp_index++; 900 } 901 902 all_points.extend (phantoms); 903 } 904 else return false; 905 906 return true; 907 } 908 get_points_bearing_appliedOT::glyf::accelerator_t909 bool get_points_bearing_applied (hb_font_t *font, hb_codepoint_t gid, contour_point_vector_t &all_points) const 910 { 911 if (unlikely (!get_points_var (gid, font->coords, font->num_coords, all_points) || 912 all_points.length < PHANTOM_COUNT)) return false; 913 914 /* Undocumented rasterizer behavior: 915 * Shift points horizontally by the updated left side bearing 916 */ 917 contour_point_t delta; 918 delta.init (-all_points[all_points.length - PHANTOM_COUNT + PHANTOM_LEFT].x, 0.f); 919 if (delta.x) all_points.translate (delta); 920 return true; 921 } 922 923 protected: 924 get_var_extents_and_phantomsOT::glyf::accelerator_t925 bool get_var_extents_and_phantoms (hb_font_t *font, hb_codepoint_t gid, 926 hb_glyph_extents_t *extents=nullptr /* OUT */, 927 contour_point_vector_t *phantoms=nullptr /* OUT */) const 928 { 929 contour_point_vector_t all_points; 930 if (!unlikely (get_points_bearing_applied (font, gid, all_points))) return false; 931 if (extents) 932 { 933 contour_bounds_t bounds; 934 for (unsigned int i = 0; i + PHANTOM_COUNT < all_points.length; i++) 935 bounds.add (all_points[i]); 936 bounds.get_extents (font, extents); 937 } 938 if (phantoms) 939 for (unsigned int i = 0; i < PHANTOM_COUNT; i++) 940 (*phantoms)[i] = all_points[all_points.length - PHANTOM_COUNT + i]; 941 return true; 942 } 943 get_var_metricsOT::glyf::accelerator_t944 bool get_var_metrics (hb_font_t *font, hb_codepoint_t gid, 945 contour_point_vector_t &phantoms) const 946 { return get_var_extents_and_phantoms (font, gid, nullptr, &phantoms); } 947 get_extents_varOT::glyf::accelerator_t948 bool get_extents_var (hb_font_t *font, hb_codepoint_t gid, 949 hb_glyph_extents_t *extents) const 950 { return get_var_extents_and_phantoms (font, gid, extents); } 951 #endif 952 953 public: 954 #ifndef HB_NO_VAR get_advance_varOT::glyf::accelerator_t955 unsigned int get_advance_var (hb_font_t *font, hb_codepoint_t gid, 956 bool is_vertical) const 957 { 958 bool success = false; 959 contour_point_vector_t phantoms; 960 phantoms.resize (PHANTOM_COUNT); 961 962 if (likely (font->num_coords == face->table.gvar->get_axis_count ())) 963 success = get_var_metrics (font, gid, phantoms); 964 965 if (unlikely (!success)) 966 return is_vertical ? face->table.vmtx->get_advance (gid) : face->table.hmtx->get_advance (gid); 967 968 if (is_vertical) 969 return roundf (phantoms[PHANTOM_TOP].y - phantoms[PHANTOM_BOTTOM].y); 970 else 971 return roundf (phantoms[PHANTOM_RIGHT].x - phantoms[PHANTOM_LEFT].x); 972 } 973 get_side_bearing_varOT::glyf::accelerator_t974 int get_side_bearing_var (hb_font_t *font, hb_codepoint_t gid, bool is_vertical) const 975 { 976 hb_glyph_extents_t extents; 977 contour_point_vector_t phantoms; 978 phantoms.resize (PHANTOM_COUNT); 979 980 if (unlikely (!get_var_extents_and_phantoms (font, gid, &extents, &phantoms))) 981 return is_vertical ? face->table.vmtx->get_side_bearing (gid) : face->table.hmtx->get_side_bearing (gid); 982 983 return is_vertical ? ceil (phantoms[PHANTOM_TOP].y) - extents.y_bearing : floor (phantoms[PHANTOM_LEFT].x); 984 } 985 #endif 986 get_extentsOT::glyf::accelerator_t987 bool get_extents (hb_font_t *font, hb_codepoint_t gid, hb_glyph_extents_t *extents) const 988 { 989 #ifndef HB_NO_VAR 990 unsigned int coord_count; 991 const int *coords = hb_font_get_var_coords_normalized (font, &coord_count); 992 if (coords && coord_count > 0 && coord_count == face->table.gvar->get_axis_count ()) 993 return get_extents_var (font, gid, extents); 994 #endif 995 996 if (unlikely (gid >= num_glyphs)) return false; 997 998 return glyph_for_gid (gid).get_extents (font, gid, extents); 999 } 1000 1001 const Glyph glyph_for_gidOT::glyf::accelerator_t1002 glyph_for_gid (hb_codepoint_t gid, bool needs_padding_removal = false) const 1003 { 1004 unsigned int start_offset, end_offset; 1005 if (unlikely (gid >= num_glyphs)) return Glyph (); 1006 1007 if (short_offset) 1008 { 1009 const HBUINT16 *offsets = (const HBUINT16 *) loca_table->dataZ.arrayZ; 1010 start_offset = 2 * offsets[gid]; 1011 end_offset = 2 * offsets[gid + 1]; 1012 } 1013 else 1014 { 1015 const HBUINT32 *offsets = (const HBUINT32 *) loca_table->dataZ.arrayZ; 1016 start_offset = offsets[gid]; 1017 end_offset = offsets[gid + 1]; 1018 } 1019 1020 if (unlikely (start_offset > end_offset || end_offset > glyf_table.get_length ())) 1021 return Glyph (); 1022 1023 Glyph glyph (hb_bytes_t ((const char *) this->glyf_table + start_offset, 1024 end_offset - start_offset)); 1025 return needs_padding_removal ? glyph.trim_padding () : glyph; 1026 } 1027 1028 void add_gid_and_childrenOT::glyf::accelerator_t1029 add_gid_and_children (hb_codepoint_t gid, hb_set_t *gids_to_retain, 1030 unsigned int depth = 0) const 1031 { 1032 if (unlikely (depth++ > HB_MAX_NESTING_LEVEL)) return; 1033 /* Check if is already visited */ 1034 if (gids_to_retain->has (gid)) return; 1035 1036 gids_to_retain->add (gid); 1037 1038 for (auto &item : glyph_for_gid (gid).get_composite_iterator ()) 1039 add_gid_and_children (item.glyphIndex, gids_to_retain, depth); 1040 } 1041 1042 private: 1043 bool short_offset; 1044 unsigned int num_glyphs; 1045 hb_blob_ptr_t<loca> loca_table; 1046 hb_blob_ptr_t<glyf> glyf_table; 1047 hb_face_t *face; 1048 }; 1049 1050 struct SubsetGlyph 1051 { 1052 hb_codepoint_t new_gid; 1053 hb_codepoint_t old_gid; 1054 Glyph source_glyph; 1055 hb_bytes_t dest_start; /* region of source_glyph to copy first */ 1056 hb_bytes_t dest_end; /* region of source_glyph to copy second */ 1057 serializeOT::glyf::SubsetGlyph1058 bool serialize (hb_serialize_context_t *c, 1059 const hb_subset_plan_t *plan) const 1060 { 1061 TRACE_SERIALIZE (this); 1062 1063 hb_bytes_t dest_glyph = dest_start.copy (c); 1064 dest_glyph = hb_bytes_t (&dest_glyph, dest_glyph.length + dest_end.copy (c).length); 1065 unsigned int pad_length = padding (); 1066 DEBUG_MSG (SUBSET, nullptr, "serialize %d byte glyph, width %d pad %d", dest_glyph.length, dest_glyph.length + pad_length, pad_length); 1067 1068 HBUINT8 pad; 1069 pad = 0; 1070 while (pad_length > 0) 1071 { 1072 c->embed (pad); 1073 pad_length--; 1074 } 1075 1076 if (!unlikely (dest_glyph.length)) return_trace (true); 1077 1078 /* update components gids */ 1079 for (auto &_ : Glyph (dest_glyph).get_composite_iterator ()) 1080 { 1081 hb_codepoint_t new_gid; 1082 if (plan->new_gid_for_old_gid (_.glyphIndex, &new_gid)) 1083 ((OT::glyf::CompositeGlyphChain *) &_)->glyphIndex = new_gid; 1084 } 1085 1086 if (plan->drop_hints) Glyph (dest_glyph).drop_hints (); 1087 1088 return_trace (true); 1089 } 1090 drop_hints_bytesOT::glyf::SubsetGlyph1091 void drop_hints_bytes () 1092 { source_glyph.drop_hints_bytes (dest_start, dest_end); } 1093 lengthOT::glyf::SubsetGlyph1094 unsigned int length () const { return dest_start.length + dest_end.length; } 1095 /* pad to 2 to ensure 2-byte loca will be ok */ paddingOT::glyf::SubsetGlyph1096 unsigned int padding () const { return length () % 2; } padded_sizeOT::glyf::SubsetGlyph1097 unsigned int padded_size () const { return length () + padding (); } 1098 }; 1099 1100 protected: 1101 UnsizedArrayOf<HBUINT8> 1102 dataZ; /* Glyphs data. */ 1103 public: 1104 DEFINE_SIZE_MIN (0); /* In reality, this is UNBOUNDED() type; but since we always 1105 * check the size externally, allow Null() object of it by 1106 * defining it _MIN instead. */ 1107 }; 1108 1109 struct glyf_accelerator_t : glyf::accelerator_t {}; 1110 1111 } /* namespace OT */ 1112 1113 1114 #endif /* HB_OT_GLYF_TABLE_HH */ 1115