hb-ot-shape.cc revision 5aec2fb8d0a4db52ae414d980b66018ca5ce1e9c
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 44static 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 53static 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 64static void 65hb_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 map->add_global_bool_feature (HB_TAG('r','v','r','n')); 73 map->add_gsub_pause (NULL); 74 75 switch (props->direction) { 76 case HB_DIRECTION_LTR: 77 map->add_global_bool_feature (HB_TAG ('l','t','r','a')); 78 map->add_global_bool_feature (HB_TAG ('l','t','r','m')); 79 break; 80 case HB_DIRECTION_RTL: 81 map->add_global_bool_feature (HB_TAG ('r','t','l','a')); 82 map->add_feature (HB_TAG ('r','t','l','m'), 1, F_NONE); 83 break; 84 case HB_DIRECTION_TTB: 85 case HB_DIRECTION_BTT: 86 case HB_DIRECTION_INVALID: 87 default: 88 break; 89 } 90 91 map->add_feature (HB_TAG ('f','r','a','c'), 1, F_NONE); 92 map->add_feature (HB_TAG ('n','u','m','r'), 1, F_NONE); 93 map->add_feature (HB_TAG ('d','n','o','m'), 1, F_NONE); 94 95 if (planner->shaper->collect_features) 96 planner->shaper->collect_features (planner); 97 98 for (unsigned int i = 0; i < ARRAY_LENGTH (common_features); i++) 99 map->add_global_bool_feature (common_features[i]); 100 101 if (HB_DIRECTION_IS_HORIZONTAL (props->direction)) 102 for (unsigned int i = 0; i < ARRAY_LENGTH (horizontal_features); i++) 103 map->add_feature (horizontal_features[i], 1, F_GLOBAL | 104 (horizontal_features[i] == HB_TAG('k','e','r','n') ? 105 F_HAS_FALLBACK : F_NONE)); 106 else 107 { 108 /* We really want to find a 'vert' feature if there's any in the font, no 109 * matter which script/langsys it is listed (or not) under. 110 * See various bugs referenced from: 111 * https://github.com/behdad/harfbuzz/issues/63 */ 112 map->add_feature (HB_TAG ('v','e','r','t'), 1, F_GLOBAL | F_GLOBAL_SEARCH); 113 } 114 115 if (planner->shaper->override_features) 116 planner->shaper->override_features (planner); 117 118 for (unsigned int i = 0; i < num_user_features; i++) { 119 const hb_feature_t *feature = &user_features[i]; 120 map->add_feature (feature->tag, feature->value, 121 (feature->start == 0 && feature->end == (unsigned int) -1) ? 122 F_GLOBAL : F_NONE); 123 } 124} 125 126 127/* 128 * shaper face data 129 */ 130 131HB_SHAPER_DATA_ENSURE_DEFINE(ot, face) 132 133hb_ot_shaper_face_data_t * 134_hb_ot_shaper_face_data_create (hb_face_t *face) 135{ 136 return _hb_ot_layout_create (face); 137} 138 139void 140_hb_ot_shaper_face_data_destroy (hb_ot_shaper_face_data_t *data) 141{ 142 _hb_ot_layout_destroy (data); 143} 144 145 146/* 147 * shaper font data 148 */ 149 150HB_SHAPER_DATA_ENSURE_DEFINE(ot, font) 151 152struct hb_ot_shaper_font_data_t {}; 153 154hb_ot_shaper_font_data_t * 155_hb_ot_shaper_font_data_create (hb_font_t *font HB_UNUSED) 156{ 157 return (hb_ot_shaper_font_data_t *) HB_SHAPER_DATA_SUCCEEDED; 158} 159 160void 161_hb_ot_shaper_font_data_destroy (hb_ot_shaper_font_data_t *data) 162{ 163} 164 165 166/* 167 * shaper shape_plan data 168 */ 169 170hb_ot_shaper_shape_plan_data_t * 171_hb_ot_shaper_shape_plan_data_create (hb_shape_plan_t *shape_plan, 172 const hb_feature_t *user_features, 173 unsigned int num_user_features, 174 const int *coords, 175 unsigned int num_coords) 176{ 177 hb_ot_shape_plan_t *plan = (hb_ot_shape_plan_t *) calloc (1, sizeof (hb_ot_shape_plan_t)); 178 if (unlikely (!plan)) 179 return NULL; 180 181 hb_ot_shape_planner_t planner (shape_plan); 182 183 planner.shaper = hb_ot_shape_complex_categorize (&planner); 184 185 hb_ot_shape_collect_features (&planner, &shape_plan->props, 186 user_features, num_user_features); 187 188 planner.compile (*plan, coords, num_coords); 189 190 if (plan->shaper->data_create) { 191 plan->data = plan->shaper->data_create (plan); 192 if (unlikely (!plan->data)) 193 return NULL; 194 } 195 196 return plan; 197} 198 199void 200_hb_ot_shaper_shape_plan_data_destroy (hb_ot_shaper_shape_plan_data_t *plan) 201{ 202 if (plan->shaper->data_destroy) 203 plan->shaper->data_destroy (const_cast<void *> (plan->data)); 204 205 plan->finish (); 206 207 free (plan); 208} 209 210 211/* 212 * shaper 213 */ 214 215struct hb_ot_shape_context_t 216{ 217 hb_ot_shape_plan_t *plan; 218 hb_font_t *font; 219 hb_face_t *face; 220 hb_buffer_t *buffer; 221 const hb_feature_t *user_features; 222 unsigned int num_user_features; 223 224 /* Transient stuff */ 225 bool fallback_positioning; 226 bool fallback_glyph_classes; 227 hb_direction_t target_direction; 228}; 229 230 231 232/* Main shaper */ 233 234 235/* Prepare */ 236 237static void 238hb_set_unicode_props (hb_buffer_t *buffer) 239{ 240 unsigned int count = buffer->len; 241 hb_glyph_info_t *info = buffer->info; 242 for (unsigned int i = 0; i < count; i++) 243 _hb_glyph_info_set_unicode_props (&info[i], buffer); 244} 245 246static void 247hb_insert_dotted_circle (hb_buffer_t *buffer, hb_font_t *font) 248{ 249 if (!(buffer->flags & HB_BUFFER_FLAG_BOT) || 250 buffer->context_len[0] || 251 _hb_glyph_info_get_general_category (&buffer->info[0]) != 252 HB_UNICODE_GENERAL_CATEGORY_NON_SPACING_MARK) 253 return; 254 255 if (!font->has_glyph (0x25CCu)) 256 return; 257 258 hb_glyph_info_t dottedcircle = {0}; 259 dottedcircle.codepoint = 0x25CCu; 260 _hb_glyph_info_set_unicode_props (&dottedcircle, buffer); 261 262 buffer->clear_output (); 263 264 buffer->idx = 0; 265 hb_glyph_info_t info = dottedcircle; 266 info.cluster = buffer->cur().cluster; 267 info.mask = buffer->cur().mask; 268 buffer->output_info (info); 269 while (buffer->idx < buffer->len && !buffer->in_error) 270 buffer->next_glyph (); 271 272 buffer->swap_buffers (); 273} 274 275static void 276hb_form_clusters (hb_buffer_t *buffer) 277{ 278 if (!(buffer->scratch_flags & HB_BUFFER_SCRATCH_FLAG_HAS_NON_ASCII) || 279 buffer->cluster_level != HB_BUFFER_CLUSTER_LEVEL_MONOTONE_GRAPHEMES) 280 return; 281 282 /* Loop duplicated in hb_ensure_native_direction(), and in _hb-coretext.cc */ 283 unsigned int base = 0; 284 unsigned int count = buffer->len; 285 hb_glyph_info_t *info = buffer->info; 286 for (unsigned int i = 1; i < count; i++) 287 { 288 if (likely (!HB_UNICODE_GENERAL_CATEGORY_IS_MARK (_hb_glyph_info_get_general_category (&info[i])) && 289 !_hb_glyph_info_is_joiner (&info[i]))) 290 { 291 buffer->merge_clusters (base, i); 292 base = i; 293 } 294 } 295 buffer->merge_clusters (base, count); 296} 297 298static void 299hb_ensure_native_direction (hb_buffer_t *buffer) 300{ 301 hb_direction_t direction = buffer->props.direction; 302 303 /* TODO vertical: 304 * The only BTT vertical script is Ogham, but it's not clear to me whether OpenType 305 * Ogham fonts are supposed to be implemented BTT or not. Need to research that 306 * first. */ 307 if ((HB_DIRECTION_IS_HORIZONTAL (direction) && direction != hb_script_get_horizontal_direction (buffer->props.script)) || 308 (HB_DIRECTION_IS_VERTICAL (direction) && direction != HB_DIRECTION_TTB)) 309 { 310 /* Same loop as hb_form_clusters(). 311 * Since form_clusters() merged clusters already, we don't merge. */ 312 unsigned int base = 0; 313 unsigned int count = buffer->len; 314 hb_glyph_info_t *info = buffer->info; 315 for (unsigned int i = 1; i < count; i++) 316 { 317 if (likely (!HB_UNICODE_GENERAL_CATEGORY_IS_MARK (_hb_glyph_info_get_general_category (&info[i])))) 318 { 319 if (buffer->cluster_level == HB_BUFFER_CLUSTER_LEVEL_MONOTONE_CHARACTERS) 320 buffer->merge_clusters (base, i); 321 buffer->reverse_range (base, i); 322 323 base = i; 324 } 325 } 326 if (buffer->cluster_level == HB_BUFFER_CLUSTER_LEVEL_MONOTONE_CHARACTERS) 327 buffer->merge_clusters (base, count); 328 buffer->reverse_range (base, count); 329 330 buffer->reverse (); 331 332 buffer->props.direction = HB_DIRECTION_REVERSE (buffer->props.direction); 333 } 334} 335 336 337/* Substitute */ 338 339static inline void 340hb_ot_mirror_chars (hb_ot_shape_context_t *c) 341{ 342 if (HB_DIRECTION_IS_FORWARD (c->target_direction)) 343 return; 344 345 hb_buffer_t *buffer = c->buffer; 346 hb_unicode_funcs_t *unicode = buffer->unicode; 347 hb_mask_t rtlm_mask = c->plan->rtlm_mask; 348 349 unsigned int count = buffer->len; 350 hb_glyph_info_t *info = buffer->info; 351 for (unsigned int i = 0; i < count; i++) { 352 hb_codepoint_t codepoint = unicode->mirroring (info[i].codepoint); 353 if (likely (codepoint == info[i].codepoint || !c->font->has_glyph (codepoint))) 354 info[i].mask |= rtlm_mask; 355 else 356 info[i].codepoint = codepoint; 357 } 358} 359 360static inline void 361hb_ot_shape_setup_masks_fraction (hb_ot_shape_context_t *c) 362{ 363 if (!(c->buffer->scratch_flags & HB_BUFFER_SCRATCH_FLAG_HAS_NON_ASCII) || 364 !c->plan->has_frac) 365 return; 366 367 hb_buffer_t *buffer = c->buffer; 368 369 hb_mask_t pre_mask, post_mask; 370 if (HB_DIRECTION_IS_FORWARD (buffer->props.direction)) 371 { 372 pre_mask = c->plan->numr_mask | c->plan->frac_mask; 373 post_mask = c->plan->frac_mask | c->plan->dnom_mask; 374 } 375 else 376 { 377 pre_mask = c->plan->frac_mask | c->plan->dnom_mask; 378 post_mask = c->plan->numr_mask | c->plan->frac_mask; 379 } 380 381 unsigned int count = buffer->len; 382 hb_glyph_info_t *info = buffer->info; 383 for (unsigned int i = 0; i < count; i++) 384 { 385 if (info[i].codepoint == 0x2044u) /* FRACTION SLASH */ 386 { 387 unsigned int start = i, end = i + 1; 388 while (start && 389 _hb_glyph_info_get_general_category (&info[start - 1]) == 390 HB_UNICODE_GENERAL_CATEGORY_DECIMAL_NUMBER) 391 start--; 392 while (end < count && 393 _hb_glyph_info_get_general_category (&info[end]) == 394 HB_UNICODE_GENERAL_CATEGORY_DECIMAL_NUMBER) 395 end++; 396 397 for (unsigned int j = start; j < i; j++) 398 info[j].mask |= pre_mask; 399 info[i].mask |= c->plan->frac_mask; 400 for (unsigned int j = i + 1; j < end; j++) 401 info[j].mask |= post_mask; 402 403 i = end - 1; 404 } 405 } 406} 407 408static inline void 409hb_ot_shape_initialize_masks (hb_ot_shape_context_t *c) 410{ 411 hb_ot_map_t *map = &c->plan->map; 412 hb_buffer_t *buffer = c->buffer; 413 414 hb_mask_t global_mask = map->get_global_mask (); 415 buffer->reset_masks (global_mask); 416} 417 418static inline void 419hb_ot_shape_setup_masks (hb_ot_shape_context_t *c) 420{ 421 hb_ot_map_t *map = &c->plan->map; 422 hb_buffer_t *buffer = c->buffer; 423 424 hb_ot_shape_setup_masks_fraction (c); 425 426 if (c->plan->shaper->setup_masks) 427 c->plan->shaper->setup_masks (c->plan, buffer, c->font); 428 429 for (unsigned int i = 0; i < c->num_user_features; i++) 430 { 431 const hb_feature_t *feature = &c->user_features[i]; 432 if (!(feature->start == 0 && feature->end == (unsigned int)-1)) { 433 unsigned int shift; 434 hb_mask_t mask = map->get_mask (feature->tag, &shift); 435 buffer->set_masks (feature->value << shift, mask, feature->start, feature->end); 436 } 437 } 438} 439 440static void 441hb_ot_zero_width_default_ignorables (hb_ot_shape_context_t *c) 442{ 443 hb_buffer_t *buffer = c->buffer; 444 445 if (!(buffer->scratch_flags & HB_BUFFER_SCRATCH_FLAG_HAS_DEFAULT_IGNORABLES) || 446 (buffer->flags & HB_BUFFER_FLAG_PRESERVE_DEFAULT_IGNORABLES)) 447 return; 448 449 unsigned int count = buffer->len; 450 hb_glyph_info_t *info = buffer->info; 451 hb_glyph_position_t *pos = buffer->pos; 452 unsigned int i = 0; 453 for (i = 0; i < count; i++) 454 if (unlikely (_hb_glyph_info_is_default_ignorable (&info[i]))) 455 pos[i].x_advance = pos[i].y_advance = pos[i].x_offset = pos[i].y_offset = 0; 456} 457 458static void 459hb_ot_hide_default_ignorables (hb_ot_shape_context_t *c) 460{ 461 hb_buffer_t *buffer = c->buffer; 462 463 if (!(buffer->scratch_flags & HB_BUFFER_SCRATCH_FLAG_HAS_DEFAULT_IGNORABLES) || 464 (buffer->flags & HB_BUFFER_FLAG_PRESERVE_DEFAULT_IGNORABLES)) 465 return; 466 467 unsigned int count = buffer->len; 468 hb_glyph_info_t *info = buffer->info; 469 hb_glyph_position_t *pos = buffer->pos; 470 unsigned int i = 0; 471 for (i = 0; i < count; i++) 472 { 473 if (unlikely (_hb_glyph_info_is_default_ignorable (&info[i]))) 474 break; 475 } 476 477 /* No default-ignorables found; return. */ 478 if (i == count) 479 return; 480 481 hb_codepoint_t space; 482 if (c->font->get_nominal_glyph (' ', &space)) 483 { 484 /* Replace default-ignorables with a zero-advance space glyph. */ 485 for (/*continue*/; i < count; i++) 486 { 487 if (_hb_glyph_info_is_default_ignorable (&info[i])) 488 info[i].codepoint = space; 489 } 490 } 491 else 492 { 493 /* Merge clusters and delete default-ignorables. 494 * NOTE! We can't use out-buffer as we have positioning data. */ 495 unsigned int j = i; 496 for (; i < count; i++) 497 { 498 if (_hb_glyph_info_is_default_ignorable (&info[i])) 499 { 500 /* Merge clusters. 501 * Same logic as buffer->delete_glyph(), but for in-place removal. */ 502 503 unsigned int cluster = info[i].cluster; 504 if (i + 1 < count && cluster == info[i + 1].cluster) 505 continue; /* Cluster survives; do nothing. */ 506 507 if (j) 508 { 509 /* Merge cluster backward. */ 510 if (cluster < info[j - 1].cluster) 511 { 512 unsigned int old_cluster = info[j - 1].cluster; 513 for (unsigned k = j; k && info[k - 1].cluster == old_cluster; k--) 514 info[k - 1].cluster = cluster; 515 } 516 continue; 517 } 518 519 if (i + 1 < count) 520 buffer->merge_clusters (i, i + 2); /* Merge cluster forward. */ 521 522 continue; 523 } 524 525 if (j != i) 526 { 527 info[j] = info[i]; 528 pos[j] = pos[i]; 529 } 530 j++; 531 } 532 buffer->len = j; 533 } 534} 535 536 537static inline void 538hb_ot_map_glyphs_fast (hb_buffer_t *buffer) 539{ 540 /* Normalization process sets up glyph_index(), we just copy it. */ 541 unsigned int count = buffer->len; 542 hb_glyph_info_t *info = buffer->info; 543 for (unsigned int i = 0; i < count; i++) 544 info[i].codepoint = info[i].glyph_index(); 545 546 buffer->content_type = HB_BUFFER_CONTENT_TYPE_GLYPHS; 547} 548 549static inline void 550hb_synthesize_glyph_classes (hb_ot_shape_context_t *c) 551{ 552 unsigned int count = c->buffer->len; 553 hb_glyph_info_t *info = c->buffer->info; 554 for (unsigned int i = 0; i < count; i++) 555 { 556 hb_ot_layout_glyph_props_flags_t klass; 557 558 /* Never mark default-ignorables as marks. 559 * They won't get in the way of lookups anyway, 560 * but having them as mark will cause them to be skipped 561 * over if the lookup-flag says so, but at least for the 562 * Mongolian variation selectors, looks like Uniscribe 563 * marks them as non-mark. Some Mongolian fonts without 564 * GDEF rely on this. Another notable character that 565 * this applies to is COMBINING GRAPHEME JOINER. */ 566 klass = (_hb_glyph_info_get_general_category (&info[i]) != 567 HB_UNICODE_GENERAL_CATEGORY_NON_SPACING_MARK || 568 _hb_glyph_info_is_default_ignorable (&info[i])) ? 569 HB_OT_LAYOUT_GLYPH_PROPS_BASE_GLYPH : 570 HB_OT_LAYOUT_GLYPH_PROPS_MARK; 571 _hb_glyph_info_set_glyph_props (&info[i], klass); 572 } 573} 574 575static inline void 576hb_ot_substitute_default (hb_ot_shape_context_t *c) 577{ 578 hb_buffer_t *buffer = c->buffer; 579 580 hb_ot_shape_initialize_masks (c); 581 582 hb_ot_mirror_chars (c); 583 584 HB_BUFFER_ALLOCATE_VAR (buffer, glyph_index); 585 586 _hb_ot_shape_normalize (c->plan, buffer, c->font); 587 588 hb_ot_shape_setup_masks (c); 589 590 /* This is unfortunate to go here, but necessary... */ 591 if (c->fallback_positioning) 592 _hb_ot_shape_fallback_position_recategorize_marks (c->plan, c->font, buffer); 593 594 hb_ot_map_glyphs_fast (buffer); 595 596 HB_BUFFER_DEALLOCATE_VAR (buffer, glyph_index); 597} 598 599static inline void 600hb_ot_substitute_complex (hb_ot_shape_context_t *c) 601{ 602 hb_buffer_t *buffer = c->buffer; 603 604 hb_ot_layout_substitute_start (c->font, buffer); 605 606 if (!hb_ot_layout_has_glyph_classes (c->face)) 607 hb_synthesize_glyph_classes (c); 608 609 c->plan->substitute (c->font, buffer); 610 611 return; 612} 613 614static inline void 615hb_ot_substitute (hb_ot_shape_context_t *c) 616{ 617 hb_ot_substitute_default (c); 618 619 _hb_buffer_allocate_gsubgpos_vars (c->buffer); 620 621 hb_ot_substitute_complex (c); 622} 623 624/* Position */ 625 626static inline void 627adjust_mark_offsets (hb_glyph_position_t *pos) 628{ 629 pos->x_offset -= pos->x_advance; 630 pos->y_offset -= pos->y_advance; 631} 632 633static inline void 634zero_mark_width (hb_glyph_position_t *pos) 635{ 636 pos->x_advance = 0; 637 pos->y_advance = 0; 638} 639 640static inline void 641zero_mark_widths_by_gdef (hb_buffer_t *buffer, bool adjust_offsets) 642{ 643 unsigned int count = buffer->len; 644 hb_glyph_info_t *info = buffer->info; 645 for (unsigned int i = 0; i < count; i++) 646 if (_hb_glyph_info_is_mark (&info[i])) 647 { 648 if (adjust_offsets) 649 adjust_mark_offsets (&buffer->pos[i]); 650 zero_mark_width (&buffer->pos[i]); 651 } 652} 653 654static inline void 655hb_ot_position_default (hb_ot_shape_context_t *c) 656{ 657 hb_direction_t direction = c->buffer->props.direction; 658 unsigned int count = c->buffer->len; 659 hb_glyph_info_t *info = c->buffer->info; 660 hb_glyph_position_t *pos = c->buffer->pos; 661 662 if (HB_DIRECTION_IS_HORIZONTAL (direction)) 663 { 664 for (unsigned int i = 0; i < count; i++) 665 pos[i].x_advance = c->font->get_glyph_h_advance (info[i].codepoint); 666 /* The nil glyph_h_origin() func returns 0, so no need to apply it. */ 667 if (c->font->has_glyph_h_origin_func ()) 668 for (unsigned int i = 0; i < count; i++) 669 c->font->subtract_glyph_h_origin (info[i].codepoint, 670 &pos[i].x_offset, 671 &pos[i].y_offset); 672 } 673 else 674 { 675 for (unsigned int i = 0; i < count; i++) 676 { 677 pos[i].y_advance = c->font->get_glyph_v_advance (info[i].codepoint); 678 c->font->subtract_glyph_v_origin (info[i].codepoint, 679 &pos[i].x_offset, 680 &pos[i].y_offset); 681 } 682 } 683 if (c->buffer->scratch_flags & HB_BUFFER_SCRATCH_FLAG_HAS_SPACE_FALLBACK) 684 _hb_ot_shape_fallback_spaces (c->plan, c->font, c->buffer); 685} 686 687static inline void 688hb_ot_position_complex (hb_ot_shape_context_t *c) 689{ 690 hb_ot_layout_position_start (c->font, c->buffer); 691 692 unsigned int count = c->buffer->len; 693 694 /* If the font has no GPOS, AND, no fallback positioning will 695 * happen, AND, direction is forward, then when zeroing mark 696 * widths, we shift the mark with it, such that the mark 697 * is positioned hanging over the previous glyph. When 698 * direction is backward we don't shift and it will end up 699 * hanging over the next glyph after the final reordering. 700 * If fallback positinoing happens or GPOS is present, we don't 701 * care. 702 */ 703 bool adjust_offsets_when_zeroing = c->fallback_positioning && 704 !c->plan->shaper->fallback_position && 705 HB_DIRECTION_IS_FORWARD (c->buffer->props.direction); 706 707 switch (c->plan->shaper->zero_width_marks) 708 { 709 case HB_OT_SHAPE_ZERO_WIDTH_MARKS_BY_GDEF_EARLY: 710 zero_mark_widths_by_gdef (c->buffer, adjust_offsets_when_zeroing); 711 break; 712 713 default: 714 case HB_OT_SHAPE_ZERO_WIDTH_MARKS_NONE: 715 case HB_OT_SHAPE_ZERO_WIDTH_MARKS_BY_GDEF_LATE: 716 break; 717 } 718 719 if (likely (!c->fallback_positioning)) 720 { 721 hb_glyph_info_t *info = c->buffer->info; 722 hb_glyph_position_t *pos = c->buffer->pos; 723 724 /* Change glyph origin to what GPOS expects (horizontal), apply GPOS, change it back. */ 725 726 /* The nil glyph_h_origin() func returns 0, so no need to apply it. */ 727 if (c->font->has_glyph_h_origin_func ()) 728 for (unsigned int i = 0; i < count; i++) 729 c->font->add_glyph_h_origin (info[i].codepoint, 730 &pos[i].x_offset, 731 &pos[i].y_offset); 732 733 c->plan->position (c->font, c->buffer); 734 735 /* The nil glyph_h_origin() func returns 0, so no need to apply it. */ 736 if (c->font->has_glyph_h_origin_func ()) 737 for (unsigned int i = 0; i < count; i++) 738 c->font->subtract_glyph_h_origin (info[i].codepoint, 739 &pos[i].x_offset, 740 &pos[i].y_offset); 741 742 } 743 744 switch (c->plan->shaper->zero_width_marks) 745 { 746 case HB_OT_SHAPE_ZERO_WIDTH_MARKS_BY_GDEF_LATE: 747 zero_mark_widths_by_gdef (c->buffer, adjust_offsets_when_zeroing); 748 break; 749 750 default: 751 case HB_OT_SHAPE_ZERO_WIDTH_MARKS_NONE: 752 case HB_OT_SHAPE_ZERO_WIDTH_MARKS_BY_GDEF_EARLY: 753 break; 754 } 755 756 /* Finishing off GPOS has to follow a certain order. */ 757 hb_ot_layout_position_finish_advances (c->font, c->buffer); 758 hb_ot_zero_width_default_ignorables (c); 759 hb_ot_layout_position_finish_offsets (c->font, c->buffer); 760} 761 762static inline void 763hb_ot_position (hb_ot_shape_context_t *c) 764{ 765 c->buffer->clear_positions (); 766 767 hb_ot_position_default (c); 768 769 hb_ot_position_complex (c); 770 771 if (c->fallback_positioning && c->plan->shaper->fallback_position) 772 _hb_ot_shape_fallback_position (c->plan, c->font, c->buffer); 773 774 if (HB_DIRECTION_IS_BACKWARD (c->buffer->props.direction)) 775 hb_buffer_reverse (c->buffer); 776 777 /* Visual fallback goes here. */ 778 779 if (c->fallback_positioning) 780 _hb_ot_shape_fallback_kern (c->plan, c->font, c->buffer); 781 782 _hb_buffer_deallocate_gsubgpos_vars (c->buffer); 783} 784 785 786/* Pull it all together! */ 787 788static void 789hb_ot_shape_internal (hb_ot_shape_context_t *c) 790{ 791 c->buffer->deallocate_var_all (); 792 c->buffer->scratch_flags = HB_BUFFER_SCRATCH_FLAG_DEFAULT; 793 if (likely (!_hb_unsigned_int_mul_overflows (c->buffer->len, HB_BUFFER_MAX_EXPANSION_FACTOR))) 794 { 795 c->buffer->max_len = MAX (c->buffer->len * HB_BUFFER_MAX_EXPANSION_FACTOR, 796 (unsigned) HB_BUFFER_MAX_LEN_MIN); 797 } 798 799 bool disable_otl = c->plan->shaper->disable_otl && c->plan->shaper->disable_otl (c->plan); 800 //c->fallback_substitute = disable_otl || !hb_ot_layout_has_substitution (c->face); 801 c->fallback_positioning = disable_otl || !hb_ot_layout_has_positioning (c->face); 802 c->fallback_glyph_classes = disable_otl || !hb_ot_layout_has_glyph_classes (c->face); 803 804 /* Save the original direction, we use it later. */ 805 c->target_direction = c->buffer->props.direction; 806 807 _hb_buffer_allocate_unicode_vars (c->buffer); 808 809 c->buffer->clear_output (); 810 811 hb_set_unicode_props (c->buffer); 812 hb_insert_dotted_circle (c->buffer, c->font); 813 hb_form_clusters (c->buffer); 814 815 hb_ensure_native_direction (c->buffer); 816 817 if (c->plan->shaper->preprocess_text) 818 c->plan->shaper->preprocess_text (c->plan, c->buffer, c->font); 819 820 hb_ot_substitute (c); 821 hb_ot_position (c); 822 823 hb_ot_hide_default_ignorables (c); 824 825 if (c->plan->shaper->postprocess_glyphs) 826 c->plan->shaper->postprocess_glyphs (c->plan, c->buffer, c->font); 827 828 _hb_buffer_deallocate_unicode_vars (c->buffer); 829 830 c->buffer->props.direction = c->target_direction; 831 832 c->buffer->max_len = HB_BUFFER_MAX_LEN_DEFAULT; 833 c->buffer->deallocate_var_all (); 834} 835 836 837hb_bool_t 838_hb_ot_shape (hb_shape_plan_t *shape_plan, 839 hb_font_t *font, 840 hb_buffer_t *buffer, 841 const hb_feature_t *features, 842 unsigned int num_features) 843{ 844 hb_ot_shape_context_t c = {HB_SHAPER_DATA_GET (shape_plan), font, font->face, buffer, features, num_features}; 845 hb_ot_shape_internal (&c); 846 847 return true; 848} 849 850 851/** 852 * hb_ot_shape_plan_collect_lookups: 853 * 854 * Since: 0.9.7 855 **/ 856void 857hb_ot_shape_plan_collect_lookups (hb_shape_plan_t *shape_plan, 858 hb_tag_t table_tag, 859 hb_set_t *lookup_indexes /* OUT */) 860{ 861 /* XXX Does the first part always succeed? */ 862 HB_SHAPER_DATA_GET (shape_plan)->collect_lookups (table_tag, lookup_indexes); 863} 864 865 866/* TODO Move this to hb-ot-shape-normalize, make it do decompose, and make it public. */ 867static void 868add_char (hb_font_t *font, 869 hb_unicode_funcs_t *unicode, 870 hb_bool_t mirror, 871 hb_codepoint_t u, 872 hb_set_t *glyphs) 873{ 874 hb_codepoint_t glyph; 875 if (font->get_nominal_glyph (u, &glyph)) 876 glyphs->add (glyph); 877 if (mirror) 878 { 879 hb_codepoint_t m = unicode->mirroring (u); 880 if (m != u && font->get_nominal_glyph (m, &glyph)) 881 glyphs->add (glyph); 882 } 883} 884 885 886/** 887 * hb_ot_shape_glyphs_closure: 888 * 889 * Since: 0.9.2 890 **/ 891void 892hb_ot_shape_glyphs_closure (hb_font_t *font, 893 hb_buffer_t *buffer, 894 const hb_feature_t *features, 895 unsigned int num_features, 896 hb_set_t *glyphs) 897{ 898 hb_ot_shape_plan_t plan; 899 900 const char *shapers[] = {"ot", NULL}; 901 hb_shape_plan_t *shape_plan = hb_shape_plan_create_cached (font->face, &buffer->props, 902 features, num_features, shapers); 903 904 bool mirror = hb_script_get_horizontal_direction (buffer->props.script) == HB_DIRECTION_RTL; 905 906 unsigned int count = buffer->len; 907 hb_glyph_info_t *info = buffer->info; 908 for (unsigned int i = 0; i < count; i++) 909 add_char (font, buffer->unicode, mirror, info[i].codepoint, glyphs); 910 911 hb_set_t lookups; 912 lookups.init (); 913 hb_ot_shape_plan_collect_lookups (shape_plan, HB_OT_TAG_GSUB, &lookups); 914 915 /* And find transitive closure. */ 916 hb_set_t copy; 917 copy.init (); 918 do { 919 copy.set (glyphs); 920 for (hb_codepoint_t lookup_index = -1; hb_set_next (&lookups, &lookup_index);) 921 hb_ot_layout_lookup_substitute_closure (font->face, lookup_index, glyphs); 922 } while (!copy.is_equal (glyphs)); 923 924 hb_shape_plan_destroy (shape_plan); 925} 926