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