1 /* 2 * Copyright 2009,2010 Red Hat, Inc. 3 * Copyright 2010,2011,2012 Google, Inc. 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 * Red Hat Author(s): Behdad Esfahbod 26 * Google Author(s): Behdad Esfahbod 27 */ 28 29 #define HB_SHAPER ot 30 #define hb_ot_shaper_face_data_t hb_ot_layout_t 31 #define hb_ot_shaper_shape_plan_data_t hb_ot_shape_plan_t 32 #include "hb-shaper-impl-private.hh" 33 34 #include "hb-ot-shape-private.hh" 35 #include "hb-ot-shape-complex-private.hh" 36 #include "hb-ot-shape-fallback-private.hh" 37 #include "hb-ot-shape-normalize-private.hh" 38 39 #include "hb-ot-layout-private.hh" 40 #include "hb-unicode-private.hh" 41 #include "hb-set-private.hh" 42 43 44 static hb_tag_t common_features[] = { 45 HB_TAG('c','c','m','p'), 46 HB_TAG('l','o','c','l'), 47 HB_TAG('m','a','r','k'), 48 HB_TAG('m','k','m','k'), 49 HB_TAG('r','l','i','g'), 50 }; 51 52 53 static hb_tag_t horizontal_features[] = { 54 HB_TAG('c','a','l','t'), 55 HB_TAG('c','l','i','g'), 56 HB_TAG('c','u','r','s'), 57 HB_TAG('k','e','r','n'), 58 HB_TAG('l','i','g','a'), 59 HB_TAG('r','c','l','t'), 60 }; 61 62 63 64 static void 65 hb_ot_shape_collect_features (hb_ot_shape_planner_t *planner, 66 const hb_segment_properties_t *props, 67 const hb_feature_t *user_features, 68 unsigned int num_user_features) 69 { 70 hb_ot_map_builder_t *map = &planner->map; 71 72 switch (props->direction) { 73 case HB_DIRECTION_LTR: 74 map->add_global_bool_feature (HB_TAG ('l','t','r','a')); 75 map->add_global_bool_feature (HB_TAG ('l','t','r','m')); 76 break; 77 case HB_DIRECTION_RTL: 78 map->add_global_bool_feature (HB_TAG ('r','t','l','a')); 79 map->add_feature (HB_TAG ('r','t','l','m'), 1, F_NONE); 80 break; 81 case HB_DIRECTION_TTB: 82 case HB_DIRECTION_BTT: 83 case HB_DIRECTION_INVALID: 84 default: 85 break; 86 } 87 88 map->add_feature (HB_TAG ('f','r','a','c'), 1, F_NONE); 89 map->add_feature (HB_TAG ('n','u','m','r'), 1, F_NONE); 90 map->add_feature (HB_TAG ('d','n','o','m'), 1, F_NONE); 91 92 if (planner->shaper->collect_features) 93 planner->shaper->collect_features (planner); 94 95 for (unsigned int i = 0; i < ARRAY_LENGTH (common_features); i++) 96 map->add_global_bool_feature (common_features[i]); 97 98 if (HB_DIRECTION_IS_HORIZONTAL (props->direction)) 99 for (unsigned int i = 0; i < ARRAY_LENGTH (horizontal_features); i++) 100 map->add_feature (horizontal_features[i], 1, F_GLOBAL | 101 (horizontal_features[i] == HB_TAG('k','e','r','n') ? 102 F_HAS_FALLBACK : F_NONE)); 103 else 104 { 105 /* We really want to find a 'vert' feature if there's any in the font, no 106 * matter which script/langsys it is listed (or not) under. 107 * See various bugs referenced from: 108 * https://github.com/behdad/harfbuzz/issues/63 */ 109 map->add_feature (HB_TAG ('v','e','r','t'), 1, F_GLOBAL | F_GLOBAL_SEARCH); 110 } 111 112 if (planner->shaper->override_features) 113 planner->shaper->override_features (planner); 114 115 for (unsigned int i = 0; i < num_user_features; i++) { 116 const hb_feature_t *feature = &user_features[i]; 117 map->add_feature (feature->tag, feature->value, 118 (feature->start == 0 && feature->end == (unsigned int) -1) ? 119 F_GLOBAL : F_NONE); 120 } 121 } 122 123 124 /* 125 * shaper face data 126 */ 127 128 hb_ot_shaper_face_data_t * 129 _hb_ot_shaper_face_data_create (hb_face_t *face) 130 { 131 return _hb_ot_layout_create (face); 132 } 133 134 void 135 _hb_ot_shaper_face_data_destroy (hb_ot_shaper_face_data_t *data) 136 { 137 _hb_ot_layout_destroy (data); 138 } 139 140 141 /* 142 * shaper font data 143 */ 144 145 struct hb_ot_shaper_font_data_t {}; 146 147 hb_ot_shaper_font_data_t * 148 _hb_ot_shaper_font_data_create (hb_font_t *font HB_UNUSED) 149 { 150 return (hb_ot_shaper_font_data_t *) HB_SHAPER_DATA_SUCCEEDED; 151 } 152 153 void 154 _hb_ot_shaper_font_data_destroy (hb_ot_shaper_font_data_t *data) 155 { 156 } 157 158 159 /* 160 * shaper shape_plan data 161 */ 162 163 hb_ot_shaper_shape_plan_data_t * 164 _hb_ot_shaper_shape_plan_data_create (hb_shape_plan_t *shape_plan, 165 const hb_feature_t *user_features, 166 unsigned int num_user_features) 167 { 168 hb_ot_shape_plan_t *plan = (hb_ot_shape_plan_t *) calloc (1, sizeof (hb_ot_shape_plan_t)); 169 if (unlikely (!plan)) 170 return NULL; 171 172 hb_ot_shape_planner_t planner (shape_plan); 173 174 planner.shaper = hb_ot_shape_complex_categorize (&planner); 175 176 hb_ot_shape_collect_features (&planner, &shape_plan->props, user_features, num_user_features); 177 178 planner.compile (*plan); 179 180 if (plan->shaper->data_create) { 181 plan->data = plan->shaper->data_create (plan); 182 if (unlikely (!plan->data)) 183 return NULL; 184 } 185 186 return plan; 187 } 188 189 void 190 _hb_ot_shaper_shape_plan_data_destroy (hb_ot_shaper_shape_plan_data_t *plan) 191 { 192 if (plan->shaper->data_destroy) 193 plan->shaper->data_destroy (const_cast<void *> (plan->data)); 194 195 plan->finish (); 196 197 free (plan); 198 } 199 200 201 /* 202 * shaper 203 */ 204 205 struct hb_ot_shape_context_t 206 { 207 hb_ot_shape_plan_t *plan; 208 hb_font_t *font; 209 hb_face_t *face; 210 hb_buffer_t *buffer; 211 const hb_feature_t *user_features; 212 unsigned int num_user_features; 213 214 /* Transient stuff */ 215 hb_direction_t target_direction; 216 }; 217 218 219 220 /* Main shaper */ 221 222 223 /* Prepare */ 224 225 static void 226 hb_set_unicode_props (hb_buffer_t *buffer) 227 { 228 unsigned int count = buffer->len; 229 hb_glyph_info_t *info = buffer->info; 230 for (unsigned int i = 0; i < count; i++) 231 _hb_glyph_info_set_unicode_props (&info[i], buffer); 232 } 233 234 static void 235 hb_insert_dotted_circle (hb_buffer_t *buffer, hb_font_t *font) 236 { 237 if (!(buffer->flags & HB_BUFFER_FLAG_BOT) || 238 buffer->context_len[0] || 239 _hb_glyph_info_get_general_category (&buffer->info[0]) != 240 HB_UNICODE_GENERAL_CATEGORY_NON_SPACING_MARK) 241 return; 242 243 if (!font->has_glyph (0x25CCu)) 244 return; 245 246 hb_glyph_info_t dottedcircle = {0}; 247 dottedcircle.codepoint = 0x25CCu; 248 _hb_glyph_info_set_unicode_props (&dottedcircle, buffer); 249 250 buffer->clear_output (); 251 252 buffer->idx = 0; 253 hb_glyph_info_t info = dottedcircle; 254 info.cluster = buffer->cur().cluster; 255 info.mask = buffer->cur().mask; 256 buffer->output_info (info); 257 while (buffer->idx < buffer->len && !buffer->in_error) 258 buffer->next_glyph (); 259 260 buffer->swap_buffers (); 261 } 262 263 static void 264 hb_form_clusters (hb_buffer_t *buffer) 265 { 266 if (!(buffer->scratch_flags & HB_BUFFER_SCRATCH_FLAG_HAS_NON_ASCII) || 267 buffer->cluster_level != HB_BUFFER_CLUSTER_LEVEL_MONOTONE_GRAPHEMES) 268 return; 269 270 /* Loop duplicated in hb_ensure_native_direction(), and in _hb-coretext.cc */ 271 unsigned int base = 0; 272 unsigned int count = buffer->len; 273 hb_glyph_info_t *info = buffer->info; 274 for (unsigned int i = 1; i < count; i++) 275 { 276 if (likely (!HB_UNICODE_GENERAL_CATEGORY_IS_MARK (_hb_glyph_info_get_general_category (&info[i])) && 277 !_hb_glyph_info_is_joiner (&info[i]))) 278 { 279 buffer->merge_clusters (base, i); 280 base = i; 281 } 282 } 283 buffer->merge_clusters (base, count); 284 } 285 286 static void 287 hb_ensure_native_direction (hb_buffer_t *buffer) 288 { 289 hb_direction_t direction = buffer->props.direction; 290 291 /* TODO vertical: 292 * The only BTT vertical script is Ogham, but it's not clear to me whether OpenType 293 * Ogham fonts are supposed to be implemented BTT or not. Need to research that 294 * first. */ 295 if ((HB_DIRECTION_IS_HORIZONTAL (direction) && direction != hb_script_get_horizontal_direction (buffer->props.script)) || 296 (HB_DIRECTION_IS_VERTICAL (direction) && direction != HB_DIRECTION_TTB)) 297 { 298 /* Same loop as hb_form_clusters(). 299 * Since form_clusters() merged clusters already, we don't merge. */ 300 unsigned int base = 0; 301 unsigned int count = buffer->len; 302 hb_glyph_info_t *info = buffer->info; 303 for (unsigned int i = 1; i < count; i++) 304 { 305 if (likely (!HB_UNICODE_GENERAL_CATEGORY_IS_MARK (_hb_glyph_info_get_general_category (&info[i])))) 306 { 307 if (buffer->cluster_level == HB_BUFFER_CLUSTER_LEVEL_MONOTONE_CHARACTERS) 308 buffer->merge_clusters (base, i); 309 buffer->reverse_range (base, i); 310 311 base = i; 312 } 313 } 314 if (buffer->cluster_level == HB_BUFFER_CLUSTER_LEVEL_MONOTONE_CHARACTERS) 315 buffer->merge_clusters (base, count); 316 buffer->reverse_range (base, count); 317 318 buffer->reverse (); 319 320 buffer->props.direction = HB_DIRECTION_REVERSE (buffer->props.direction); 321 } 322 } 323 324 325 /* Substitute */ 326 327 static inline void 328 hb_ot_mirror_chars (hb_ot_shape_context_t *c) 329 { 330 if (HB_DIRECTION_IS_FORWARD (c->target_direction)) 331 return; 332 333 hb_buffer_t *buffer = c->buffer; 334 hb_unicode_funcs_t *unicode = buffer->unicode; 335 hb_mask_t rtlm_mask = c->plan->rtlm_mask; 336 337 unsigned int count = buffer->len; 338 hb_glyph_info_t *info = buffer->info; 339 for (unsigned int i = 0; i < count; i++) { 340 hb_codepoint_t codepoint = unicode->mirroring (info[i].codepoint); 341 if (likely (codepoint == info[i].codepoint || !c->font->has_glyph (codepoint))) 342 info[i].mask |= rtlm_mask; 343 else 344 info[i].codepoint = codepoint; 345 } 346 } 347 348 static inline void 349 hb_ot_shape_setup_masks_fraction (hb_ot_shape_context_t *c) 350 { 351 if (!(c->buffer->scratch_flags & HB_BUFFER_SCRATCH_FLAG_HAS_NON_ASCII) || 352 !c->plan->has_frac) 353 return; 354 355 hb_buffer_t *buffer = c->buffer; 356 357 /* TODO look in pre/post context text also. */ 358 unsigned int count = buffer->len; 359 hb_glyph_info_t *info = buffer->info; 360 for (unsigned int i = 0; i < count; i++) 361 { 362 if (info[i].codepoint == 0x2044u) /* FRACTION SLASH */ 363 { 364 unsigned int start = i, end = i + 1; 365 while (start && 366 _hb_glyph_info_get_general_category (&info[start - 1]) == 367 HB_UNICODE_GENERAL_CATEGORY_DECIMAL_NUMBER) 368 start--; 369 while (end < count && 370 _hb_glyph_info_get_general_category (&info[end]) == 371 HB_UNICODE_GENERAL_CATEGORY_DECIMAL_NUMBER) 372 end++; 373 374 for (unsigned int j = start; j < i; j++) 375 info[j].mask |= c->plan->numr_mask | c->plan->frac_mask; 376 info[i].mask |= c->plan->frac_mask; 377 for (unsigned int j = i + 1; j < end; j++) 378 info[j].mask |= c->plan->frac_mask | c->plan->dnom_mask; 379 380 i = end - 1; 381 } 382 } 383 } 384 385 static inline void 386 hb_ot_shape_initialize_masks (hb_ot_shape_context_t *c) 387 { 388 hb_ot_map_t *map = &c->plan->map; 389 hb_buffer_t *buffer = c->buffer; 390 391 hb_mask_t global_mask = map->get_global_mask (); 392 buffer->reset_masks (global_mask); 393 } 394 395 static inline void 396 hb_ot_shape_setup_masks (hb_ot_shape_context_t *c) 397 { 398 hb_ot_map_t *map = &c->plan->map; 399 hb_buffer_t *buffer = c->buffer; 400 401 hb_ot_shape_setup_masks_fraction (c); 402 403 if (c->plan->shaper->setup_masks) 404 c->plan->shaper->setup_masks (c->plan, buffer, c->font); 405 406 for (unsigned int i = 0; i < c->num_user_features; i++) 407 { 408 const hb_feature_t *feature = &c->user_features[i]; 409 if (!(feature->start == 0 && feature->end == (unsigned int)-1)) { 410 unsigned int shift; 411 hb_mask_t mask = map->get_mask (feature->tag, &shift); 412 buffer->set_masks (feature->value << shift, mask, feature->start, feature->end); 413 } 414 } 415 } 416 417 static void 418 hb_ot_zero_width_default_ignorables (hb_ot_shape_context_t *c) 419 { 420 hb_buffer_t *buffer = c->buffer; 421 422 if (!(buffer->scratch_flags & HB_BUFFER_SCRATCH_FLAG_HAS_DEFAULT_IGNORABLES) || 423 (buffer->flags & HB_BUFFER_FLAG_PRESERVE_DEFAULT_IGNORABLES)) 424 return; 425 426 unsigned int count = buffer->len; 427 hb_glyph_info_t *info = buffer->info; 428 hb_glyph_position_t *pos = buffer->pos; 429 unsigned int i = 0; 430 for (i = 0; i < count; i++) 431 if (unlikely (_hb_glyph_info_is_default_ignorable (&info[i]))) 432 pos[i].x_advance = pos[i].y_advance = pos[i].x_offset = pos[i].y_offset = 0; 433 } 434 435 static void 436 hb_ot_hide_default_ignorables (hb_ot_shape_context_t *c) 437 { 438 hb_buffer_t *buffer = c->buffer; 439 440 if (!(buffer->scratch_flags & HB_BUFFER_SCRATCH_FLAG_HAS_DEFAULT_IGNORABLES) || 441 (buffer->flags & HB_BUFFER_FLAG_PRESERVE_DEFAULT_IGNORABLES)) 442 return; 443 444 unsigned int count = buffer->len; 445 hb_glyph_info_t *info = buffer->info; 446 hb_glyph_position_t *pos = buffer->pos; 447 unsigned int i = 0; 448 for (i = 0; i < count; i++) 449 { 450 if (unlikely (_hb_glyph_info_is_default_ignorable (&info[i]))) 451 break; 452 } 453 454 /* No default-ignorables found; return. */ 455 if (i == count) 456 return; 457 458 hb_codepoint_t space; 459 if (c->font->get_nominal_glyph (' ', &space)) 460 { 461 /* Replace default-ignorables with a zero-advance space glyph. */ 462 for (/*continue*/; i < count; i++) 463 { 464 if (_hb_glyph_info_is_default_ignorable (&info[i])) 465 info[i].codepoint = space; 466 } 467 } 468 else 469 { 470 /* Merge clusters and delete default-ignorables. 471 * NOTE! We can't use out-buffer as we have positioning data. */ 472 unsigned int j = i; 473 for (; i < count; i++) 474 { 475 if (_hb_glyph_info_is_default_ignorable (&info[i])) 476 { 477 /* Merge clusters. 478 * Same logic as buffer->delete_glyph(), but for in-place removal. */ 479 480 unsigned int cluster = info[i].cluster; 481 if (i + 1 < count && cluster == info[i + 1].cluster) 482 continue; /* Cluster survives; do nothing. */ 483 484 if (j) 485 { 486 /* Merge cluster backward. */ 487 if (cluster < info[j - 1].cluster) 488 { 489 unsigned int old_cluster = info[j - 1].cluster; 490 for (unsigned k = j; k && info[k - 1].cluster == old_cluster; k--) 491 info[k - 1].cluster = cluster; 492 } 493 continue; 494 } 495 496 if (i + 1 < count) 497 buffer->merge_clusters (i, i + 2); /* Merge cluster forward. */ 498 499 continue; 500 } 501 502 if (j != i) 503 { 504 info[j] = info[i]; 505 pos[j] = pos[i]; 506 } 507 j++; 508 } 509 buffer->len = j; 510 } 511 } 512 513 514 static inline void 515 hb_ot_map_glyphs_fast (hb_buffer_t *buffer) 516 { 517 /* Normalization process sets up glyph_index(), we just copy it. */ 518 unsigned int count = buffer->len; 519 hb_glyph_info_t *info = buffer->info; 520 for (unsigned int i = 0; i < count; i++) 521 info[i].codepoint = info[i].glyph_index(); 522 523 buffer->content_type = HB_BUFFER_CONTENT_TYPE_GLYPHS; 524 } 525 526 static inline void 527 hb_ot_substitute_default (hb_ot_shape_context_t *c) 528 { 529 hb_buffer_t *buffer = c->buffer; 530 531 hb_ot_shape_initialize_masks (c); 532 533 hb_ot_mirror_chars (c); 534 535 HB_BUFFER_ALLOCATE_VAR (buffer, glyph_index); 536 537 _hb_ot_shape_normalize (c->plan, buffer, c->font); 538 539 hb_ot_shape_setup_masks (c); 540 541 /* This is unfortunate to go here, but necessary... */ 542 if (!hb_ot_layout_has_positioning (c->face)) 543 _hb_ot_shape_fallback_position_recategorize_marks (c->plan, c->font, buffer); 544 545 hb_ot_map_glyphs_fast (buffer); 546 547 HB_BUFFER_DEALLOCATE_VAR (buffer, glyph_index); 548 } 549 550 static inline void 551 hb_ot_substitute_complex (hb_ot_shape_context_t *c) 552 { 553 hb_buffer_t *buffer = c->buffer; 554 555 hb_ot_layout_substitute_start (c->font, buffer); 556 557 c->plan->substitute (c->font, buffer); 558 559 return; 560 } 561 562 static inline void 563 hb_ot_substitute (hb_ot_shape_context_t *c) 564 { 565 hb_ot_substitute_default (c); 566 567 _hb_buffer_allocate_gsubgpos_vars (c->buffer); 568 569 hb_ot_substitute_complex (c); 570 } 571 572 /* Position */ 573 574 static inline void 575 adjust_mark_offsets (hb_glyph_position_t *pos) 576 { 577 pos->x_offset -= pos->x_advance; 578 pos->y_offset -= pos->y_advance; 579 } 580 581 static inline void 582 zero_mark_width (hb_glyph_position_t *pos) 583 { 584 pos->x_advance = 0; 585 pos->y_advance = 0; 586 } 587 588 static inline void 589 zero_mark_widths_by_gdef (hb_buffer_t *buffer, bool adjust_offsets) 590 { 591 unsigned int count = buffer->len; 592 hb_glyph_info_t *info = buffer->info; 593 for (unsigned int i = 0; i < count; i++) 594 if (_hb_glyph_info_is_mark (&info[i])) 595 { 596 if (adjust_offsets) 597 adjust_mark_offsets (&buffer->pos[i]); 598 zero_mark_width (&buffer->pos[i]); 599 } 600 } 601 602 static inline void 603 hb_ot_position_default (hb_ot_shape_context_t *c) 604 { 605 hb_direction_t direction = c->buffer->props.direction; 606 unsigned int count = c->buffer->len; 607 hb_glyph_info_t *info = c->buffer->info; 608 hb_glyph_position_t *pos = c->buffer->pos; 609 610 if (HB_DIRECTION_IS_HORIZONTAL (direction)) 611 { 612 for (unsigned int i = 0; i < count; i++) 613 pos[i].x_advance = c->font->get_glyph_h_advance (info[i].codepoint); 614 /* The nil glyph_h_origin() func returns 0, so no need to apply it. */ 615 if (c->font->has_glyph_h_origin_func ()) 616 for (unsigned int i = 0; i < count; i++) 617 c->font->subtract_glyph_h_origin (info[i].codepoint, 618 &pos[i].x_offset, 619 &pos[i].y_offset); 620 } 621 else 622 { 623 for (unsigned int i = 0; i < count; i++) 624 { 625 pos[i].y_advance = c->font->get_glyph_v_advance (info[i].codepoint); 626 c->font->subtract_glyph_v_origin (info[i].codepoint, 627 &pos[i].x_offset, 628 &pos[i].y_offset); 629 } 630 } 631 if (c->buffer->scratch_flags & HB_BUFFER_SCRATCH_FLAG_HAS_SPACE_FALLBACK) 632 _hb_ot_shape_fallback_spaces (c->plan, c->font, c->buffer); 633 } 634 635 static inline bool 636 hb_ot_position_complex (hb_ot_shape_context_t *c) 637 { 638 hb_ot_layout_position_start (c->font, c->buffer); 639 640 bool ret = false; 641 unsigned int count = c->buffer->len; 642 bool has_positioning = (bool) hb_ot_layout_has_positioning (c->face); 643 644 /* If the font has no GPOS, AND, no fallback positioning will 645 * happen, AND, direction is forward, then when zeroing mark 646 * widths, we shift the mark with it, such that the mark 647 * is positioned hanging over the previous glyph. When 648 * direction is backward we don't shift and it will end up 649 * hanging over the next glyph after the final reordering. 650 * If fallback positinoing happens or GPOS is present, we don't 651 * care. 652 */ 653 bool adjust_offsets_when_zeroing = !(has_positioning || c->plan->shaper->fallback_position || 654 HB_DIRECTION_IS_BACKWARD (c->buffer->props.direction)); 655 656 switch (c->plan->shaper->zero_width_marks) 657 { 658 case HB_OT_SHAPE_ZERO_WIDTH_MARKS_BY_GDEF_EARLY: 659 zero_mark_widths_by_gdef (c->buffer, adjust_offsets_when_zeroing); 660 break; 661 662 default: 663 case HB_OT_SHAPE_ZERO_WIDTH_MARKS_NONE: 664 case HB_OT_SHAPE_ZERO_WIDTH_MARKS_BY_GDEF_LATE: 665 break; 666 } 667 668 if (has_positioning) 669 { 670 hb_glyph_info_t *info = c->buffer->info; 671 hb_glyph_position_t *pos = c->buffer->pos; 672 673 /* Change glyph origin to what GPOS expects (horizontal), apply GPOS, change it back. */ 674 675 /* The nil glyph_h_origin() func returns 0, so no need to apply it. */ 676 if (c->font->has_glyph_h_origin_func ()) 677 for (unsigned int i = 0; i < count; i++) 678 c->font->add_glyph_h_origin (info[i].codepoint, 679 &pos[i].x_offset, 680 &pos[i].y_offset); 681 682 c->plan->position (c->font, c->buffer); 683 684 /* The nil glyph_h_origin() func returns 0, so no need to apply it. */ 685 if (c->font->has_glyph_h_origin_func ()) 686 for (unsigned int i = 0; i < count; i++) 687 c->font->subtract_glyph_h_origin (info[i].codepoint, 688 &pos[i].x_offset, 689 &pos[i].y_offset); 690 691 ret = true; 692 } 693 694 switch (c->plan->shaper->zero_width_marks) 695 { 696 case HB_OT_SHAPE_ZERO_WIDTH_MARKS_BY_GDEF_LATE: 697 zero_mark_widths_by_gdef (c->buffer, adjust_offsets_when_zeroing); 698 break; 699 700 default: 701 case HB_OT_SHAPE_ZERO_WIDTH_MARKS_NONE: 702 case HB_OT_SHAPE_ZERO_WIDTH_MARKS_BY_GDEF_EARLY: 703 break; 704 } 705 706 /* Finishing off GPOS has to follow a certain order. */ 707 hb_ot_layout_position_finish_advances (c->font, c->buffer); 708 hb_ot_zero_width_default_ignorables (c); 709 hb_ot_layout_position_finish_offsets (c->font, c->buffer); 710 711 return ret; 712 } 713 714 static inline void 715 hb_ot_position (hb_ot_shape_context_t *c) 716 { 717 c->buffer->clear_positions (); 718 719 hb_ot_position_default (c); 720 721 hb_bool_t fallback = !hb_ot_position_complex (c); 722 723 if (fallback && c->plan->shaper->fallback_position) 724 _hb_ot_shape_fallback_position (c->plan, c->font, c->buffer); 725 726 if (HB_DIRECTION_IS_BACKWARD (c->buffer->props.direction)) 727 hb_buffer_reverse (c->buffer); 728 729 /* Visual fallback goes here. */ 730 731 if (fallback) 732 _hb_ot_shape_fallback_kern (c->plan, c->font, c->buffer); 733 734 _hb_buffer_deallocate_gsubgpos_vars (c->buffer); 735 } 736 737 738 /* Pull it all together! */ 739 740 static void 741 hb_ot_shape_internal (hb_ot_shape_context_t *c) 742 { 743 c->buffer->deallocate_var_all (); 744 c->buffer->scratch_flags = HB_BUFFER_SCRATCH_FLAG_DEFAULT; 745 if (likely (!_hb_unsigned_int_mul_overflows (c->buffer->len, HB_BUFFER_MAX_EXPANSION_FACTOR))) 746 { 747 c->buffer->max_len = MAX (c->buffer->len * HB_BUFFER_MAX_EXPANSION_FACTOR, 748 (unsigned) HB_BUFFER_MAX_LEN_MIN); 749 } 750 751 /* Save the original direction, we use it later. */ 752 c->target_direction = c->buffer->props.direction; 753 754 _hb_buffer_allocate_unicode_vars (c->buffer); 755 756 c->buffer->clear_output (); 757 758 hb_set_unicode_props (c->buffer); 759 hb_insert_dotted_circle (c->buffer, c->font); 760 hb_form_clusters (c->buffer); 761 762 hb_ensure_native_direction (c->buffer); 763 764 if (c->plan->shaper->preprocess_text) 765 c->plan->shaper->preprocess_text (c->plan, c->buffer, c->font); 766 767 hb_ot_substitute (c); 768 hb_ot_position (c); 769 770 hb_ot_hide_default_ignorables (c); 771 772 if (c->plan->shaper->postprocess_glyphs) 773 c->plan->shaper->postprocess_glyphs (c->plan, c->buffer, c->font); 774 775 _hb_buffer_deallocate_unicode_vars (c->buffer); 776 777 c->buffer->props.direction = c->target_direction; 778 779 c->buffer->max_len = HB_BUFFER_MAX_LEN_DEFAULT; 780 c->buffer->deallocate_var_all (); 781 } 782 783 784 hb_bool_t 785 _hb_ot_shape (hb_shape_plan_t *shape_plan, 786 hb_font_t *font, 787 hb_buffer_t *buffer, 788 const hb_feature_t *features, 789 unsigned int num_features) 790 { 791 hb_ot_shape_context_t c = {HB_SHAPER_DATA_GET (shape_plan), font, font->face, buffer, features, num_features}; 792 hb_ot_shape_internal (&c); 793 794 return true; 795 } 796 797 798 /** 799 * hb_ot_shape_plan_collect_lookups: 800 * 801 * Since: 0.9.7 802 **/ 803 void 804 hb_ot_shape_plan_collect_lookups (hb_shape_plan_t *shape_plan, 805 hb_tag_t table_tag, 806 hb_set_t *lookup_indexes /* OUT */) 807 { 808 /* XXX Does the first part always succeed? */ 809 HB_SHAPER_DATA_GET (shape_plan)->collect_lookups (table_tag, lookup_indexes); 810 } 811 812 813 /* TODO Move this to hb-ot-shape-normalize, make it do decompose, and make it public. */ 814 static void 815 add_char (hb_font_t *font, 816 hb_unicode_funcs_t *unicode, 817 hb_bool_t mirror, 818 hb_codepoint_t u, 819 hb_set_t *glyphs) 820 { 821 hb_codepoint_t glyph; 822 if (font->get_nominal_glyph (u, &glyph)) 823 glyphs->add (glyph); 824 if (mirror) 825 { 826 hb_codepoint_t m = unicode->mirroring (u); 827 if (m != u && font->get_nominal_glyph (m, &glyph)) 828 glyphs->add (glyph); 829 } 830 } 831 832 833 /** 834 * hb_ot_shape_glyphs_closure: 835 * 836 * Since: 0.9.2 837 **/ 838 void 839 hb_ot_shape_glyphs_closure (hb_font_t *font, 840 hb_buffer_t *buffer, 841 const hb_feature_t *features, 842 unsigned int num_features, 843 hb_set_t *glyphs) 844 { 845 hb_ot_shape_plan_t plan; 846 847 const char *shapers[] = {"ot", NULL}; 848 hb_shape_plan_t *shape_plan = hb_shape_plan_create_cached (font->face, &buffer->props, 849 features, num_features, shapers); 850 851 bool mirror = hb_script_get_horizontal_direction (buffer->props.script) == HB_DIRECTION_RTL; 852 853 unsigned int count = buffer->len; 854 hb_glyph_info_t *info = buffer->info; 855 for (unsigned int i = 0; i < count; i++) 856 add_char (font, buffer->unicode, mirror, info[i].codepoint, glyphs); 857 858 hb_set_t lookups; 859 lookups.init (); 860 hb_ot_shape_plan_collect_lookups (shape_plan, HB_OT_TAG_GSUB, &lookups); 861 862 /* And find transitive closure. */ 863 hb_set_t copy; 864 copy.init (); 865 do { 866 copy.set (glyphs); 867 for (hb_codepoint_t lookup_index = -1; hb_set_next (&lookups, &lookup_index);) 868 hb_ot_layout_lookup_substitute_closure (font->face, lookup_index, glyphs); 869 } while (!copy.is_equal (glyphs)); 870 871 hb_shape_plan_destroy (shape_plan); 872 } 873
