1 /**************************************************************************** 2 * 3 * aflatin.c 4 * 5 * Auto-fitter hinting routines for latin writing system (body). 6 * 7 * Copyright (C) 2003-2020 by 8 * David Turner, Robert Wilhelm, and Werner Lemberg. 9 * 10 * This file is part of the FreeType project, and may only be used, 11 * modified, and distributed under the terms of the FreeType project 12 * license, LICENSE.TXT. By continuing to use, modify, or distribute 13 * this file you indicate that you have read the license and 14 * understand and accept it fully. 15 * 16 */ 17 18 19 #include <freetype/ftadvanc.h> 20 #include <freetype/internal/ftdebug.h> 21 22 #include "afglobal.h" 23 #include "aflatin.h" 24 #include "aferrors.h" 25 26 27 #ifdef AF_CONFIG_OPTION_USE_WARPER 28 #include "afwarp.h" 29 #endif 30 31 32 /************************************************************************** 33 * 34 * The macro FT_COMPONENT is used in trace mode. It is an implicit 35 * parameter of the FT_TRACE() and FT_ERROR() macros, used to print/log 36 * messages during execution. 37 */ 38 #undef FT_COMPONENT 39 #define FT_COMPONENT aflatin 40 41 42 /* needed for computation of round vs. flat segments */ 43 #define FLAT_THRESHOLD( x ) ( x / 14 ) 44 45 46 /*************************************************************************/ 47 /*************************************************************************/ 48 /***** *****/ 49 /***** L A T I N G L O B A L M E T R I C S *****/ 50 /***** *****/ 51 /*************************************************************************/ 52 /*************************************************************************/ 53 54 55 /* Find segments and links, compute all stem widths, and initialize */ 56 /* standard width and height for the glyph with given charcode. */ 57 58 FT_LOCAL_DEF( void ) af_latin_metrics_init_widths(AF_LatinMetrics metrics,FT_Face face)59 af_latin_metrics_init_widths( AF_LatinMetrics metrics, 60 FT_Face face ) 61 { 62 /* scan the array of segments in each direction */ 63 AF_GlyphHintsRec hints[1]; 64 65 66 FT_TRACE5(( "\n" 67 "latin standard widths computation (style `%s')\n" 68 "=====================================================\n" 69 "\n", 70 af_style_names[metrics->root.style_class->style] )); 71 72 af_glyph_hints_init( hints, face->memory ); 73 74 metrics->axis[AF_DIMENSION_HORZ].width_count = 0; 75 metrics->axis[AF_DIMENSION_VERT].width_count = 0; 76 77 { 78 FT_Error error; 79 FT_ULong glyph_index; 80 int dim; 81 AF_LatinMetricsRec dummy[1]; 82 AF_Scaler scaler = &dummy->root.scaler; 83 84 AF_StyleClass style_class = metrics->root.style_class; 85 AF_ScriptClass script_class = af_script_classes[style_class->script]; 86 87 /* If HarfBuzz is not available, we need a pointer to a single */ 88 /* unsigned long value. */ 89 #ifdef FT_CONFIG_OPTION_USE_HARFBUZZ 90 void* shaper_buf; 91 #else 92 FT_ULong shaper_buf_; 93 void* shaper_buf = &shaper_buf_; 94 #endif 95 96 const char* p; 97 98 #ifdef FT_DEBUG_LEVEL_TRACE 99 FT_ULong ch = 0; 100 #endif 101 102 103 p = script_class->standard_charstring; 104 105 #ifdef FT_CONFIG_OPTION_USE_HARFBUZZ 106 shaper_buf = af_shaper_buf_create( face ); 107 #endif 108 /* 109 * We check a list of standard characters to catch features like 110 * `c2sc' (small caps from caps) that don't contain lowercase letters 111 * by definition, or other features that mainly operate on numerals. 112 * The first match wins. 113 */ 114 115 glyph_index = 0; 116 while ( *p ) 117 { 118 unsigned int num_idx; 119 120 #ifdef FT_DEBUG_LEVEL_TRACE 121 const char* p_old; 122 #endif 123 124 125 while ( *p == ' ' ) 126 p++; 127 128 #ifdef FT_DEBUG_LEVEL_TRACE 129 p_old = p; 130 GET_UTF8_CHAR( ch, p_old ); 131 #endif 132 133 /* reject input that maps to more than a single glyph */ 134 p = af_shaper_get_cluster( p, &metrics->root, shaper_buf, &num_idx ); 135 if ( num_idx > 1 ) 136 continue; 137 138 /* otherwise exit loop if we have a result */ 139 glyph_index = af_shaper_get_elem( &metrics->root, 140 shaper_buf, 141 0, 142 NULL, 143 NULL ); 144 if ( glyph_index ) 145 break; 146 } 147 148 af_shaper_buf_destroy( face, shaper_buf ); 149 150 if ( !glyph_index ) 151 { 152 FT_TRACE5(( "standard character missing;" 153 " using fallback stem widths\n" )); 154 goto Exit; 155 } 156 157 FT_TRACE5(( "standard character: U+%04lX (glyph index %ld)\n", 158 ch, glyph_index )); 159 160 error = FT_Load_Glyph( face, glyph_index, FT_LOAD_NO_SCALE ); 161 if ( error || face->glyph->outline.n_points <= 0 ) 162 goto Exit; 163 164 FT_ZERO( dummy ); 165 166 dummy->units_per_em = metrics->units_per_em; 167 168 scaler->x_scale = 0x10000L; 169 scaler->y_scale = 0x10000L; 170 scaler->x_delta = 0; 171 scaler->y_delta = 0; 172 173 scaler->face = face; 174 scaler->render_mode = FT_RENDER_MODE_NORMAL; 175 scaler->flags = 0; 176 177 af_glyph_hints_rescale( hints, (AF_StyleMetrics)dummy ); 178 179 error = af_glyph_hints_reload( hints, &face->glyph->outline ); 180 if ( error ) 181 goto Exit; 182 183 for ( dim = 0; dim < AF_DIMENSION_MAX; dim++ ) 184 { 185 AF_LatinAxis axis = &metrics->axis[dim]; 186 AF_AxisHints axhints = &hints->axis[dim]; 187 AF_Segment seg, limit, link; 188 FT_UInt num_widths = 0; 189 190 191 error = af_latin_hints_compute_segments( hints, 192 (AF_Dimension)dim ); 193 if ( error ) 194 goto Exit; 195 196 /* 197 * We assume that the glyphs selected for the stem width 198 * computation are `featureless' enough so that the linking 199 * algorithm works fine without adjustments of its scoring 200 * function. 201 */ 202 af_latin_hints_link_segments( hints, 203 0, 204 NULL, 205 (AF_Dimension)dim ); 206 207 seg = axhints->segments; 208 limit = seg + axhints->num_segments; 209 210 for ( ; seg < limit; seg++ ) 211 { 212 link = seg->link; 213 214 /* we only consider stem segments there! */ 215 if ( link && link->link == seg && link > seg ) 216 { 217 FT_Pos dist; 218 219 220 dist = seg->pos - link->pos; 221 if ( dist < 0 ) 222 dist = -dist; 223 224 if ( num_widths < AF_LATIN_MAX_WIDTHS ) 225 axis->widths[num_widths++].org = dist; 226 } 227 } 228 229 /* this also replaces multiple almost identical stem widths */ 230 /* with a single one (the value 100 is heuristic) */ 231 af_sort_and_quantize_widths( &num_widths, axis->widths, 232 dummy->units_per_em / 100 ); 233 axis->width_count = num_widths; 234 } 235 236 Exit: 237 for ( dim = 0; dim < AF_DIMENSION_MAX; dim++ ) 238 { 239 AF_LatinAxis axis = &metrics->axis[dim]; 240 FT_Pos stdw; 241 242 243 stdw = ( axis->width_count > 0 ) ? axis->widths[0].org 244 : AF_LATIN_CONSTANT( metrics, 50 ); 245 246 /* let's try 20% of the smallest width */ 247 axis->edge_distance_threshold = stdw / 5; 248 axis->standard_width = stdw; 249 axis->extra_light = 0; 250 251 #ifdef FT_DEBUG_LEVEL_TRACE 252 { 253 FT_UInt i; 254 255 256 FT_TRACE5(( "%s widths:\n", 257 dim == AF_DIMENSION_VERT ? "horizontal" 258 : "vertical" )); 259 260 FT_TRACE5(( " %ld (standard)", axis->standard_width )); 261 for ( i = 1; i < axis->width_count; i++ ) 262 FT_TRACE5(( " %ld", axis->widths[i].org )); 263 264 FT_TRACE5(( "\n" )); 265 } 266 #endif 267 } 268 } 269 270 FT_TRACE5(( "\n" )); 271 272 af_glyph_hints_done( hints ); 273 } 274 275 276 static void af_latin_sort_blue(FT_UInt count,AF_LatinBlue * table)277 af_latin_sort_blue( FT_UInt count, 278 AF_LatinBlue* table ) 279 { 280 FT_UInt i, j; 281 AF_LatinBlue swap; 282 283 284 /* we sort from bottom to top */ 285 for ( i = 1; i < count; i++ ) 286 { 287 for ( j = i; j > 0; j-- ) 288 { 289 FT_Pos a, b; 290 291 292 if ( table[j - 1]->flags & ( AF_LATIN_BLUE_TOP | 293 AF_LATIN_BLUE_SUB_TOP ) ) 294 a = table[j - 1]->ref.org; 295 else 296 a = table[j - 1]->shoot.org; 297 298 if ( table[j]->flags & ( AF_LATIN_BLUE_TOP | 299 AF_LATIN_BLUE_SUB_TOP ) ) 300 b = table[j]->ref.org; 301 else 302 b = table[j]->shoot.org; 303 304 if ( b >= a ) 305 break; 306 307 swap = table[j]; 308 table[j] = table[j - 1]; 309 table[j - 1] = swap; 310 } 311 } 312 } 313 314 315 /* Find all blue zones. Flat segments give the reference points, */ 316 /* round segments the overshoot positions. */ 317 318 static int af_latin_metrics_init_blues(AF_LatinMetrics metrics,FT_Face face)319 af_latin_metrics_init_blues( AF_LatinMetrics metrics, 320 FT_Face face ) 321 { 322 FT_Pos flats [AF_BLUE_STRING_MAX_LEN]; 323 FT_Pos rounds[AF_BLUE_STRING_MAX_LEN]; 324 325 FT_UInt num_flats; 326 FT_UInt num_rounds; 327 328 AF_LatinBlue blue; 329 FT_Error error; 330 AF_LatinAxis axis = &metrics->axis[AF_DIMENSION_VERT]; 331 FT_Outline outline; 332 333 AF_StyleClass sc = metrics->root.style_class; 334 335 AF_Blue_Stringset bss = sc->blue_stringset; 336 const AF_Blue_StringRec* bs = &af_blue_stringsets[bss]; 337 338 FT_Pos flat_threshold = FLAT_THRESHOLD( metrics->units_per_em ); 339 340 /* If HarfBuzz is not available, we need a pointer to a single */ 341 /* unsigned long value. */ 342 #ifdef FT_CONFIG_OPTION_USE_HARFBUZZ 343 void* shaper_buf; 344 #else 345 FT_ULong shaper_buf_; 346 void* shaper_buf = &shaper_buf_; 347 #endif 348 349 350 /* we walk over the blue character strings as specified in the */ 351 /* style's entry in the `af_blue_stringset' array */ 352 353 FT_TRACE5(( "latin blue zones computation\n" 354 "============================\n" 355 "\n" )); 356 357 #ifdef FT_CONFIG_OPTION_USE_HARFBUZZ 358 shaper_buf = af_shaper_buf_create( face ); 359 #endif 360 361 for ( ; bs->string != AF_BLUE_STRING_MAX; bs++ ) 362 { 363 const char* p = &af_blue_strings[bs->string]; 364 FT_Pos* blue_ref; 365 FT_Pos* blue_shoot; 366 FT_Pos ascender; 367 FT_Pos descender; 368 369 370 #ifdef FT_DEBUG_LEVEL_TRACE 371 { 372 FT_Bool have_flag = 0; 373 374 375 FT_TRACE5(( "blue zone %d", axis->blue_count )); 376 377 if ( bs->properties ) 378 { 379 FT_TRACE5(( " (" )); 380 381 if ( AF_LATIN_IS_TOP_BLUE( bs ) ) 382 { 383 FT_TRACE5(( "top" )); 384 have_flag = 1; 385 } 386 else if ( AF_LATIN_IS_SUB_TOP_BLUE( bs ) ) 387 { 388 FT_TRACE5(( "sub top" )); 389 have_flag = 1; 390 } 391 392 if ( AF_LATIN_IS_NEUTRAL_BLUE( bs ) ) 393 { 394 if ( have_flag ) 395 FT_TRACE5(( ", " )); 396 FT_TRACE5(( "neutral" )); 397 have_flag = 1; 398 } 399 400 if ( AF_LATIN_IS_X_HEIGHT_BLUE( bs ) ) 401 { 402 if ( have_flag ) 403 FT_TRACE5(( ", " )); 404 FT_TRACE5(( "small top" )); 405 have_flag = 1; 406 } 407 408 if ( AF_LATIN_IS_LONG_BLUE( bs ) ) 409 { 410 if ( have_flag ) 411 FT_TRACE5(( ", " )); 412 FT_TRACE5(( "long" )); 413 } 414 415 FT_TRACE5(( ")" )); 416 } 417 418 FT_TRACE5(( ":\n" )); 419 } 420 #endif /* FT_DEBUG_LEVEL_TRACE */ 421 422 num_flats = 0; 423 num_rounds = 0; 424 ascender = 0; 425 descender = 0; 426 427 while ( *p ) 428 { 429 FT_ULong glyph_index; 430 FT_Long y_offset; 431 FT_Int best_point, best_contour_first, best_contour_last; 432 FT_Vector* points; 433 434 FT_Pos best_y_extremum; /* same as points.y */ 435 FT_Bool best_round = 0; 436 437 unsigned int i, num_idx; 438 439 #ifdef FT_DEBUG_LEVEL_TRACE 440 const char* p_old; 441 FT_ULong ch; 442 #endif 443 444 445 while ( *p == ' ' ) 446 p++; 447 448 #ifdef FT_DEBUG_LEVEL_TRACE 449 p_old = p; 450 GET_UTF8_CHAR( ch, p_old ); 451 #endif 452 453 p = af_shaper_get_cluster( p, &metrics->root, shaper_buf, &num_idx ); 454 455 if ( !num_idx ) 456 { 457 FT_TRACE5(( " U+%04lX unavailable\n", ch )); 458 continue; 459 } 460 461 if ( AF_LATIN_IS_TOP_BLUE( bs ) ) 462 best_y_extremum = FT_INT_MIN; 463 else 464 best_y_extremum = FT_INT_MAX; 465 466 /* iterate over all glyph elements of the character cluster */ 467 /* and get the data of the `biggest' one */ 468 for ( i = 0; i < num_idx; i++ ) 469 { 470 FT_Pos best_y; 471 FT_Bool round = 0; 472 473 474 /* load the character in the face -- skip unknown or empty ones */ 475 glyph_index = af_shaper_get_elem( &metrics->root, 476 shaper_buf, 477 i, 478 NULL, 479 &y_offset ); 480 if ( glyph_index == 0 ) 481 { 482 FT_TRACE5(( " U+%04lX unavailable\n", ch )); 483 continue; 484 } 485 486 error = FT_Load_Glyph( face, glyph_index, FT_LOAD_NO_SCALE ); 487 outline = face->glyph->outline; 488 /* reject glyphs that don't produce any rendering */ 489 if ( error || outline.n_points <= 2 ) 490 { 491 #ifdef FT_DEBUG_LEVEL_TRACE 492 if ( num_idx == 1 ) 493 FT_TRACE5(( " U+%04lX contains no (usable) outlines\n", ch )); 494 else 495 FT_TRACE5(( " component %d of cluster starting with U+%04lX" 496 " contains no (usable) outlines\n", i, ch )); 497 #endif 498 continue; 499 } 500 501 /* now compute min or max point indices and coordinates */ 502 points = outline.points; 503 best_point = -1; 504 best_y = 0; /* make compiler happy */ 505 best_contour_first = 0; /* ditto */ 506 best_contour_last = 0; /* ditto */ 507 508 { 509 FT_Int nn; 510 FT_Int first = 0; 511 FT_Int last = -1; 512 513 514 for ( nn = 0; nn < outline.n_contours; first = last + 1, nn++ ) 515 { 516 FT_Int old_best_point = best_point; 517 FT_Int pp; 518 519 520 last = outline.contours[nn]; 521 522 /* Avoid single-point contours since they are never */ 523 /* rasterized. In some fonts, they correspond to mark */ 524 /* attachment points that are way outside of the glyph's */ 525 /* real outline. */ 526 if ( last <= first ) 527 continue; 528 529 if ( AF_LATIN_IS_TOP_BLUE( bs ) || 530 AF_LATIN_IS_SUB_TOP_BLUE( bs ) ) 531 { 532 for ( pp = first; pp <= last; pp++ ) 533 { 534 if ( best_point < 0 || points[pp].y > best_y ) 535 { 536 best_point = pp; 537 best_y = points[pp].y; 538 ascender = FT_MAX( ascender, best_y + y_offset ); 539 } 540 else 541 descender = FT_MIN( descender, points[pp].y + y_offset ); 542 } 543 } 544 else 545 { 546 for ( pp = first; pp <= last; pp++ ) 547 { 548 if ( best_point < 0 || points[pp].y < best_y ) 549 { 550 best_point = pp; 551 best_y = points[pp].y; 552 descender = FT_MIN( descender, best_y + y_offset ); 553 } 554 else 555 ascender = FT_MAX( ascender, points[pp].y + y_offset ); 556 } 557 } 558 559 if ( best_point != old_best_point ) 560 { 561 best_contour_first = first; 562 best_contour_last = last; 563 } 564 } 565 } 566 567 /* now check whether the point belongs to a straight or round */ 568 /* segment; we first need to find in which contour the extremum */ 569 /* lies, then inspect its previous and next points */ 570 if ( best_point >= 0 ) 571 { 572 FT_Pos best_x = points[best_point].x; 573 FT_Int prev, next; 574 FT_Int best_segment_first, best_segment_last; 575 FT_Int best_on_point_first, best_on_point_last; 576 FT_Pos dist; 577 578 579 best_segment_first = best_point; 580 best_segment_last = best_point; 581 582 if ( FT_CURVE_TAG( outline.tags[best_point] ) == FT_CURVE_TAG_ON ) 583 { 584 best_on_point_first = best_point; 585 best_on_point_last = best_point; 586 } 587 else 588 { 589 best_on_point_first = -1; 590 best_on_point_last = -1; 591 } 592 593 /* look for the previous and next points on the contour */ 594 /* that are not on the same Y coordinate, then threshold */ 595 /* the `closeness'... */ 596 prev = best_point; 597 next = prev; 598 599 do 600 { 601 if ( prev > best_contour_first ) 602 prev--; 603 else 604 prev = best_contour_last; 605 606 dist = FT_ABS( points[prev].y - best_y ); 607 /* accept a small distance or a small angle (both values are */ 608 /* heuristic; value 20 corresponds to approx. 2.9 degrees) */ 609 if ( dist > 5 ) 610 if ( FT_ABS( points[prev].x - best_x ) <= 20 * dist ) 611 break; 612 613 best_segment_first = prev; 614 615 if ( FT_CURVE_TAG( outline.tags[prev] ) == FT_CURVE_TAG_ON ) 616 { 617 best_on_point_first = prev; 618 if ( best_on_point_last < 0 ) 619 best_on_point_last = prev; 620 } 621 622 } while ( prev != best_point ); 623 624 do 625 { 626 if ( next < best_contour_last ) 627 next++; 628 else 629 next = best_contour_first; 630 631 dist = FT_ABS( points[next].y - best_y ); 632 if ( dist > 5 ) 633 if ( FT_ABS( points[next].x - best_x ) <= 20 * dist ) 634 break; 635 636 best_segment_last = next; 637 638 if ( FT_CURVE_TAG( outline.tags[next] ) == FT_CURVE_TAG_ON ) 639 { 640 best_on_point_last = next; 641 if ( best_on_point_first < 0 ) 642 best_on_point_first = next; 643 } 644 645 } while ( next != best_point ); 646 647 if ( AF_LATIN_IS_LONG_BLUE( bs ) ) 648 { 649 /* If this flag is set, we have an additional constraint to */ 650 /* get the blue zone distance: Find a segment of the topmost */ 651 /* (or bottommost) contour that is longer than a heuristic */ 652 /* threshold. This ensures that small bumps in the outline */ 653 /* are ignored (for example, the `vertical serifs' found in */ 654 /* many Hebrew glyph designs). */ 655 656 /* If this segment is long enough, we are done. Otherwise, */ 657 /* search the segment next to the extremum that is long */ 658 /* enough, has the same direction, and a not too large */ 659 /* vertical distance from the extremum. Note that the */ 660 /* algorithm doesn't check whether the found segment is */ 661 /* actually the one (vertically) nearest to the extremum. */ 662 663 /* heuristic threshold value */ 664 FT_Pos length_threshold = metrics->units_per_em / 25; 665 666 667 dist = FT_ABS( points[best_segment_last].x - 668 points[best_segment_first].x ); 669 670 if ( dist < length_threshold && 671 best_segment_last - best_segment_first + 2 <= 672 best_contour_last - best_contour_first ) 673 { 674 /* heuristic threshold value */ 675 FT_Pos height_threshold = metrics->units_per_em / 4; 676 677 FT_Int first; 678 FT_Int last; 679 FT_Bool hit; 680 681 /* we intentionally declare these two variables */ 682 /* outside of the loop since various compilers emit */ 683 /* incorrect warning messages otherwise, talking about */ 684 /* `possibly uninitialized variables' */ 685 FT_Int p_first = 0; /* make compiler happy */ 686 FT_Int p_last = 0; 687 688 FT_Bool left2right; 689 690 691 /* compute direction */ 692 prev = best_point; 693 694 do 695 { 696 if ( prev > best_contour_first ) 697 prev--; 698 else 699 prev = best_contour_last; 700 701 if ( points[prev].x != best_x ) 702 break; 703 704 } while ( prev != best_point ); 705 706 /* skip glyph for the degenerate case */ 707 if ( prev == best_point ) 708 continue; 709 710 left2right = FT_BOOL( points[prev].x < points[best_point].x ); 711 712 first = best_segment_last; 713 last = first; 714 hit = 0; 715 716 do 717 { 718 FT_Bool l2r; 719 FT_Pos d; 720 721 722 if ( !hit ) 723 { 724 /* no hit; adjust first point */ 725 first = last; 726 727 /* also adjust first and last on point */ 728 if ( FT_CURVE_TAG( outline.tags[first] ) == 729 FT_CURVE_TAG_ON ) 730 { 731 p_first = first; 732 p_last = first; 733 } 734 else 735 { 736 p_first = -1; 737 p_last = -1; 738 } 739 740 hit = 1; 741 } 742 743 if ( last < best_contour_last ) 744 last++; 745 else 746 last = best_contour_first; 747 748 if ( FT_ABS( best_y - points[first].y ) > height_threshold ) 749 { 750 /* vertical distance too large */ 751 hit = 0; 752 continue; 753 } 754 755 /* same test as above */ 756 dist = FT_ABS( points[last].y - points[first].y ); 757 if ( dist > 5 ) 758 if ( FT_ABS( points[last].x - points[first].x ) <= 759 20 * dist ) 760 { 761 hit = 0; 762 continue; 763 } 764 765 if ( FT_CURVE_TAG( outline.tags[last] ) == FT_CURVE_TAG_ON ) 766 { 767 p_last = last; 768 if ( p_first < 0 ) 769 p_first = last; 770 } 771 772 l2r = FT_BOOL( points[first].x < points[last].x ); 773 d = FT_ABS( points[last].x - points[first].x ); 774 775 if ( l2r == left2right && 776 d >= length_threshold ) 777 { 778 /* all constraints are met; update segment after */ 779 /* finding its end */ 780 do 781 { 782 if ( last < best_contour_last ) 783 last++; 784 else 785 last = best_contour_first; 786 787 d = FT_ABS( points[last].y - points[first].y ); 788 if ( d > 5 ) 789 if ( FT_ABS( points[next].x - points[first].x ) <= 790 20 * dist ) 791 { 792 if ( last > best_contour_first ) 793 last--; 794 else 795 last = best_contour_last; 796 break; 797 } 798 799 p_last = last; 800 801 if ( FT_CURVE_TAG( outline.tags[last] ) == 802 FT_CURVE_TAG_ON ) 803 { 804 p_last = last; 805 if ( p_first < 0 ) 806 p_first = last; 807 } 808 809 } while ( last != best_segment_first ); 810 811 best_y = points[first].y; 812 813 best_segment_first = first; 814 best_segment_last = last; 815 816 best_on_point_first = p_first; 817 best_on_point_last = p_last; 818 819 break; 820 } 821 822 } while ( last != best_segment_first ); 823 } 824 } 825 826 /* for computing blue zones, we add the y offset as returned */ 827 /* by the currently used OpenType feature -- for example, */ 828 /* superscript glyphs might be identical to subscript glyphs */ 829 /* with a vertical shift */ 830 best_y += y_offset; 831 832 #ifdef FT_DEBUG_LEVEL_TRACE 833 if ( num_idx == 1 ) 834 FT_TRACE5(( " U+%04lX: best_y = %5ld", ch, best_y )); 835 else 836 FT_TRACE5(( " component %d of cluster starting with U+%04lX:" 837 " best_y = %5ld", i, ch, best_y )); 838 #endif 839 840 /* now set the `round' flag depending on the segment's kind: */ 841 /* */ 842 /* - if the horizontal distance between the first and last */ 843 /* `on' point is larger than a heuristic threshold */ 844 /* we have a flat segment */ 845 /* - if either the first or the last point of the segment is */ 846 /* an `off' point, the segment is round, otherwise it is */ 847 /* flat */ 848 if ( best_on_point_first >= 0 && 849 best_on_point_last >= 0 && 850 ( FT_ABS( points[best_on_point_last].x - 851 points[best_on_point_first].x ) ) > 852 flat_threshold ) 853 round = 0; 854 else 855 round = FT_BOOL( 856 FT_CURVE_TAG( outline.tags[best_segment_first] ) != 857 FT_CURVE_TAG_ON || 858 FT_CURVE_TAG( outline.tags[best_segment_last] ) != 859 FT_CURVE_TAG_ON ); 860 861 if ( round && AF_LATIN_IS_NEUTRAL_BLUE( bs ) ) 862 { 863 /* only use flat segments for a neutral blue zone */ 864 FT_TRACE5(( " (round, skipped)\n" )); 865 continue; 866 } 867 868 FT_TRACE5(( " (%s)\n", round ? "round" : "flat" )); 869 } 870 871 if ( AF_LATIN_IS_TOP_BLUE( bs ) ) 872 { 873 if ( best_y > best_y_extremum ) 874 { 875 best_y_extremum = best_y; 876 best_round = round; 877 } 878 } 879 else 880 { 881 if ( best_y < best_y_extremum ) 882 { 883 best_y_extremum = best_y; 884 best_round = round; 885 } 886 } 887 888 } /* end for loop */ 889 890 if ( !( best_y_extremum == FT_INT_MIN || 891 best_y_extremum == FT_INT_MAX ) ) 892 { 893 if ( best_round ) 894 rounds[num_rounds++] = best_y_extremum; 895 else 896 flats[num_flats++] = best_y_extremum; 897 } 898 899 } /* end while loop */ 900 901 if ( num_flats == 0 && num_rounds == 0 ) 902 { 903 /* 904 * we couldn't find a single glyph to compute this blue zone, 905 * we will simply ignore it then 906 */ 907 FT_TRACE5(( " empty\n" )); 908 continue; 909 } 910 911 /* we have computed the contents of the `rounds' and `flats' tables, */ 912 /* now determine the reference and overshoot position of the blue -- */ 913 /* we simply take the median value after a simple sort */ 914 af_sort_pos( num_rounds, rounds ); 915 af_sort_pos( num_flats, flats ); 916 917 blue = &axis->blues[axis->blue_count]; 918 blue_ref = &blue->ref.org; 919 blue_shoot = &blue->shoot.org; 920 921 axis->blue_count++; 922 923 if ( num_flats == 0 ) 924 { 925 *blue_ref = 926 *blue_shoot = rounds[num_rounds / 2]; 927 } 928 else if ( num_rounds == 0 ) 929 { 930 *blue_ref = 931 *blue_shoot = flats[num_flats / 2]; 932 } 933 else 934 { 935 *blue_ref = flats [num_flats / 2]; 936 *blue_shoot = rounds[num_rounds / 2]; 937 } 938 939 /* there are sometimes problems: if the overshoot position of top */ 940 /* zones is under its reference position, or the opposite for bottom */ 941 /* zones. We must thus check everything there and correct the errors */ 942 if ( *blue_shoot != *blue_ref ) 943 { 944 FT_Pos ref = *blue_ref; 945 FT_Pos shoot = *blue_shoot; 946 FT_Bool over_ref = FT_BOOL( shoot > ref ); 947 948 949 if ( ( AF_LATIN_IS_TOP_BLUE( bs ) || 950 AF_LATIN_IS_SUB_TOP_BLUE( bs) ) ^ over_ref ) 951 { 952 *blue_ref = 953 *blue_shoot = ( shoot + ref ) / 2; 954 955 FT_TRACE5(( " [overshoot smaller than reference," 956 " taking mean value]\n" )); 957 } 958 } 959 960 blue->ascender = ascender; 961 blue->descender = descender; 962 963 blue->flags = 0; 964 if ( AF_LATIN_IS_TOP_BLUE( bs ) ) 965 blue->flags |= AF_LATIN_BLUE_TOP; 966 if ( AF_LATIN_IS_SUB_TOP_BLUE( bs ) ) 967 blue->flags |= AF_LATIN_BLUE_SUB_TOP; 968 if ( AF_LATIN_IS_NEUTRAL_BLUE( bs ) ) 969 blue->flags |= AF_LATIN_BLUE_NEUTRAL; 970 971 /* 972 * The following flag is used later to adjust the y and x scales 973 * in order to optimize the pixel grid alignment of the top of small 974 * letters. 975 */ 976 if ( AF_LATIN_IS_X_HEIGHT_BLUE( bs ) ) 977 blue->flags |= AF_LATIN_BLUE_ADJUSTMENT; 978 979 FT_TRACE5(( " -> reference = %ld\n" 980 " overshoot = %ld\n", 981 *blue_ref, *blue_shoot )); 982 983 } /* end for loop */ 984 985 af_shaper_buf_destroy( face, shaper_buf ); 986 987 if ( axis->blue_count ) 988 { 989 /* we finally check whether blue zones are ordered; */ 990 /* `ref' and `shoot' values of two blue zones must not overlap */ 991 992 FT_UInt i; 993 AF_LatinBlue blue_sorted[AF_BLUE_STRINGSET_MAX_LEN + 2]; 994 995 996 for ( i = 0; i < axis->blue_count; i++ ) 997 blue_sorted[i] = &axis->blues[i]; 998 999 /* sort bottoms of blue zones... */ 1000 af_latin_sort_blue( axis->blue_count, blue_sorted ); 1001 1002 /* ...and adjust top values if necessary */ 1003 for ( i = 0; i < axis->blue_count - 1; i++ ) 1004 { 1005 FT_Pos* a; 1006 FT_Pos* b; 1007 1008 #ifdef FT_DEBUG_LEVEL_TRACE 1009 FT_Bool a_is_top = 0; 1010 #endif 1011 1012 1013 if ( blue_sorted[i]->flags & ( AF_LATIN_BLUE_TOP | 1014 AF_LATIN_BLUE_SUB_TOP ) ) 1015 { 1016 a = &blue_sorted[i]->shoot.org; 1017 #ifdef FT_DEBUG_LEVEL_TRACE 1018 a_is_top = 1; 1019 #endif 1020 } 1021 else 1022 a = &blue_sorted[i]->ref.org; 1023 1024 if ( blue_sorted[i + 1]->flags & ( AF_LATIN_BLUE_TOP | 1025 AF_LATIN_BLUE_SUB_TOP ) ) 1026 b = &blue_sorted[i + 1]->shoot.org; 1027 else 1028 b = &blue_sorted[i + 1]->ref.org; 1029 1030 if ( *a > *b ) 1031 { 1032 *a = *b; 1033 FT_TRACE5(( "blue zone overlap:" 1034 " adjusting %s %ld to %ld\n", 1035 a_is_top ? "overshoot" : "reference", 1036 blue_sorted[i] - axis->blues, 1037 *a )); 1038 } 1039 } 1040 1041 FT_TRACE5(( "\n" )); 1042 1043 return 0; 1044 } 1045 else 1046 { 1047 /* disable hinting for the current style if there are no blue zones */ 1048 1049 AF_FaceGlobals globals = metrics->root.globals; 1050 FT_UShort* gstyles = globals->glyph_styles; 1051 1052 FT_Long i; 1053 1054 1055 FT_TRACE5(( "no blue zones found:" 1056 " hinting disabled for this style\n" )); 1057 1058 for ( i = 0; i < globals->glyph_count; i++ ) 1059 { 1060 if ( ( gstyles[i] & AF_STYLE_MASK ) == sc->style ) 1061 gstyles[i] = AF_STYLE_NONE_DFLT; 1062 } 1063 1064 FT_TRACE5(( "\n" )); 1065 1066 return 1; 1067 } 1068 } 1069 1070 1071 /* Check whether all ASCII digits have the same advance width. */ 1072 1073 FT_LOCAL_DEF( void ) af_latin_metrics_check_digits(AF_LatinMetrics metrics,FT_Face face)1074 af_latin_metrics_check_digits( AF_LatinMetrics metrics, 1075 FT_Face face ) 1076 { 1077 FT_Bool started = 0, same_width = 1; 1078 FT_Fixed advance = 0, old_advance = 0; 1079 1080 /* If HarfBuzz is not available, we need a pointer to a single */ 1081 /* unsigned long value. */ 1082 #ifdef FT_CONFIG_OPTION_USE_HARFBUZZ 1083 void* shaper_buf; 1084 #else 1085 FT_ULong shaper_buf_; 1086 void* shaper_buf = &shaper_buf_; 1087 #endif 1088 1089 /* in all supported charmaps, digits have character codes 0x30-0x39 */ 1090 const char digits[] = "0 1 2 3 4 5 6 7 8 9"; 1091 const char* p; 1092 1093 1094 p = digits; 1095 1096 #ifdef FT_CONFIG_OPTION_USE_HARFBUZZ 1097 shaper_buf = af_shaper_buf_create( face ); 1098 #endif 1099 1100 while ( *p ) 1101 { 1102 FT_ULong glyph_index; 1103 unsigned int num_idx; 1104 1105 1106 /* reject input that maps to more than a single glyph */ 1107 p = af_shaper_get_cluster( p, &metrics->root, shaper_buf, &num_idx ); 1108 if ( num_idx > 1 ) 1109 continue; 1110 1111 glyph_index = af_shaper_get_elem( &metrics->root, 1112 shaper_buf, 1113 0, 1114 &advance, 1115 NULL ); 1116 if ( !glyph_index ) 1117 continue; 1118 1119 if ( started ) 1120 { 1121 if ( advance != old_advance ) 1122 { 1123 same_width = 0; 1124 break; 1125 } 1126 } 1127 else 1128 { 1129 old_advance = advance; 1130 started = 1; 1131 } 1132 } 1133 1134 af_shaper_buf_destroy( face, shaper_buf ); 1135 1136 metrics->root.digits_have_same_width = same_width; 1137 } 1138 1139 1140 /* Initialize global metrics. */ 1141 1142 FT_LOCAL_DEF( FT_Error ) af_latin_metrics_init(AF_LatinMetrics metrics,FT_Face face)1143 af_latin_metrics_init( AF_LatinMetrics metrics, 1144 FT_Face face ) 1145 { 1146 FT_Error error = FT_Err_Ok; 1147 1148 FT_CharMap oldmap = face->charmap; 1149 1150 1151 metrics->units_per_em = face->units_per_EM; 1152 1153 if ( !FT_Select_Charmap( face, FT_ENCODING_UNICODE ) ) 1154 { 1155 af_latin_metrics_init_widths( metrics, face ); 1156 if ( af_latin_metrics_init_blues( metrics, face ) ) 1157 { 1158 /* use internal error code to indicate missing blue zones */ 1159 error = -1; 1160 goto Exit; 1161 } 1162 af_latin_metrics_check_digits( metrics, face ); 1163 } 1164 1165 Exit: 1166 FT_Set_Charmap( face, oldmap ); 1167 return error; 1168 } 1169 1170 1171 /* Adjust scaling value, then scale and shift widths */ 1172 /* and blue zones (if applicable) for given dimension. */ 1173 1174 static void af_latin_metrics_scale_dim(AF_LatinMetrics metrics,AF_Scaler scaler,AF_Dimension dim)1175 af_latin_metrics_scale_dim( AF_LatinMetrics metrics, 1176 AF_Scaler scaler, 1177 AF_Dimension dim ) 1178 { 1179 FT_Fixed scale; 1180 FT_Pos delta; 1181 AF_LatinAxis axis; 1182 FT_UInt nn; 1183 1184 1185 if ( dim == AF_DIMENSION_HORZ ) 1186 { 1187 scale = scaler->x_scale; 1188 delta = scaler->x_delta; 1189 } 1190 else 1191 { 1192 scale = scaler->y_scale; 1193 delta = scaler->y_delta; 1194 } 1195 1196 axis = &metrics->axis[dim]; 1197 1198 if ( axis->org_scale == scale && axis->org_delta == delta ) 1199 return; 1200 1201 axis->org_scale = scale; 1202 axis->org_delta = delta; 1203 1204 /* 1205 * correct X and Y scale to optimize the alignment of the top of small 1206 * letters to the pixel grid 1207 */ 1208 { 1209 AF_LatinAxis Axis = &metrics->axis[AF_DIMENSION_VERT]; 1210 AF_LatinBlue blue = NULL; 1211 1212 1213 for ( nn = 0; nn < Axis->blue_count; nn++ ) 1214 { 1215 if ( Axis->blues[nn].flags & AF_LATIN_BLUE_ADJUSTMENT ) 1216 { 1217 blue = &Axis->blues[nn]; 1218 break; 1219 } 1220 } 1221 1222 if ( blue ) 1223 { 1224 FT_Pos scaled; 1225 FT_Pos threshold; 1226 FT_Pos fitted; 1227 FT_UInt limit; 1228 FT_UInt ppem; 1229 1230 1231 scaled = FT_MulFix( blue->shoot.org, scale ); 1232 ppem = metrics->root.scaler.face->size->metrics.x_ppem; 1233 limit = metrics->root.globals->increase_x_height; 1234 threshold = 40; 1235 1236 /* if the `increase-x-height' property is active, */ 1237 /* we round up much more often */ 1238 if ( limit && 1239 ppem <= limit && 1240 ppem >= AF_PROP_INCREASE_X_HEIGHT_MIN ) 1241 threshold = 52; 1242 1243 fitted = ( scaled + threshold ) & ~63; 1244 1245 if ( scaled != fitted ) 1246 { 1247 #if 0 1248 if ( dim == AF_DIMENSION_HORZ ) 1249 { 1250 if ( fitted < scaled ) 1251 scale -= scale / 50; /* scale *= 0.98 */ 1252 } 1253 else 1254 #endif 1255 if ( dim == AF_DIMENSION_VERT ) 1256 { 1257 FT_Pos max_height; 1258 FT_Pos dist; 1259 FT_Fixed new_scale; 1260 1261 1262 new_scale = FT_MulDiv( scale, fitted, scaled ); 1263 1264 /* the scaling should not change the result by more than two pixels */ 1265 max_height = metrics->units_per_em; 1266 1267 for ( nn = 0; nn < Axis->blue_count; nn++ ) 1268 { 1269 max_height = FT_MAX( max_height, Axis->blues[nn].ascender ); 1270 max_height = FT_MAX( max_height, -Axis->blues[nn].descender ); 1271 } 1272 1273 dist = FT_ABS( FT_MulFix( max_height, new_scale - scale ) ); 1274 dist &= ~127; 1275 1276 if ( dist == 0 ) 1277 { 1278 FT_TRACE5(( 1279 "af_latin_metrics_scale_dim:" 1280 " x height alignment (style `%s'):\n" 1281 " " 1282 " vertical scaling changed from %.5f to %.5f (by %ld%%)\n" 1283 "\n", 1284 af_style_names[metrics->root.style_class->style], 1285 scale / 65536.0, 1286 new_scale / 65536.0, 1287 ( fitted - scaled ) * 100 / scaled )); 1288 1289 scale = new_scale; 1290 } 1291 #ifdef FT_DEBUG_LEVEL_TRACE 1292 else 1293 { 1294 FT_TRACE5(( 1295 "af_latin_metrics_scale_dim:" 1296 " x height alignment (style `%s'):\n" 1297 " " 1298 " excessive vertical scaling abandoned\n" 1299 "\n", 1300 af_style_names[metrics->root.style_class->style] )); 1301 } 1302 #endif 1303 } 1304 } 1305 } 1306 } 1307 1308 axis->scale = scale; 1309 axis->delta = delta; 1310 1311 if ( dim == AF_DIMENSION_HORZ ) 1312 { 1313 metrics->root.scaler.x_scale = scale; 1314 metrics->root.scaler.x_delta = delta; 1315 } 1316 else 1317 { 1318 metrics->root.scaler.y_scale = scale; 1319 metrics->root.scaler.y_delta = delta; 1320 } 1321 1322 FT_TRACE5(( "%s widths (style `%s')\n", 1323 dim == AF_DIMENSION_HORZ ? "horizontal" : "vertical", 1324 af_style_names[metrics->root.style_class->style] )); 1325 1326 /* scale the widths */ 1327 for ( nn = 0; nn < axis->width_count; nn++ ) 1328 { 1329 AF_Width width = axis->widths + nn; 1330 1331 1332 width->cur = FT_MulFix( width->org, scale ); 1333 width->fit = width->cur; 1334 1335 FT_TRACE5(( " %ld scaled to %.2f\n", 1336 width->org, 1337 width->cur / 64.0 )); 1338 } 1339 1340 FT_TRACE5(( "\n" )); 1341 1342 /* an extra-light axis corresponds to a standard width that is */ 1343 /* smaller than 5/8 pixels */ 1344 axis->extra_light = 1345 FT_BOOL( FT_MulFix( axis->standard_width, scale ) < 32 + 8 ); 1346 1347 #ifdef FT_DEBUG_LEVEL_TRACE 1348 if ( axis->extra_light ) 1349 FT_TRACE5(( "`%s' style is extra light (at current resolution)\n" 1350 "\n", 1351 af_style_names[metrics->root.style_class->style] )); 1352 #endif 1353 1354 if ( dim == AF_DIMENSION_VERT ) 1355 { 1356 #ifdef FT_DEBUG_LEVEL_TRACE 1357 if ( axis->blue_count ) 1358 FT_TRACE5(( "blue zones (style `%s')\n", 1359 af_style_names[metrics->root.style_class->style] )); 1360 #endif 1361 1362 /* scale the blue zones */ 1363 for ( nn = 0; nn < axis->blue_count; nn++ ) 1364 { 1365 AF_LatinBlue blue = &axis->blues[nn]; 1366 FT_Pos dist; 1367 1368 1369 blue->ref.cur = FT_MulFix( blue->ref.org, scale ) + delta; 1370 blue->ref.fit = blue->ref.cur; 1371 blue->shoot.cur = FT_MulFix( blue->shoot.org, scale ) + delta; 1372 blue->shoot.fit = blue->shoot.cur; 1373 blue->flags &= ~AF_LATIN_BLUE_ACTIVE; 1374 1375 /* a blue zone is only active if it is less than 3/4 pixels tall */ 1376 dist = FT_MulFix( blue->ref.org - blue->shoot.org, scale ); 1377 if ( dist <= 48 && dist >= -48 ) 1378 { 1379 #if 0 1380 FT_Pos delta1; 1381 #endif 1382 FT_Pos delta2; 1383 1384 1385 /* use discrete values for blue zone widths */ 1386 1387 #if 0 1388 1389 /* generic, original code */ 1390 delta1 = blue->shoot.org - blue->ref.org; 1391 delta2 = delta1; 1392 if ( delta1 < 0 ) 1393 delta2 = -delta2; 1394 1395 delta2 = FT_MulFix( delta2, scale ); 1396 1397 if ( delta2 < 32 ) 1398 delta2 = 0; 1399 else if ( delta2 < 64 ) 1400 delta2 = 32 + ( ( ( delta2 - 32 ) + 16 ) & ~31 ); 1401 else 1402 delta2 = FT_PIX_ROUND( delta2 ); 1403 1404 if ( delta1 < 0 ) 1405 delta2 = -delta2; 1406 1407 blue->ref.fit = FT_PIX_ROUND( blue->ref.cur ); 1408 blue->shoot.fit = blue->ref.fit + delta2; 1409 1410 #else 1411 1412 /* simplified version due to abs(dist) <= 48 */ 1413 delta2 = dist; 1414 if ( dist < 0 ) 1415 delta2 = -delta2; 1416 1417 if ( delta2 < 32 ) 1418 delta2 = 0; 1419 else if ( delta2 < 48 ) 1420 delta2 = 32; 1421 else 1422 delta2 = 64; 1423 1424 if ( dist < 0 ) 1425 delta2 = -delta2; 1426 1427 blue->ref.fit = FT_PIX_ROUND( blue->ref.cur ); 1428 blue->shoot.fit = blue->ref.fit - delta2; 1429 1430 #endif 1431 1432 blue->flags |= AF_LATIN_BLUE_ACTIVE; 1433 } 1434 } 1435 1436 /* use sub-top blue zone only if it doesn't overlap with */ 1437 /* another (non-sup-top) blue zone; otherwise, the */ 1438 /* effect would be similar to a neutral blue zone, which */ 1439 /* is not desired here */ 1440 for ( nn = 0; nn < axis->blue_count; nn++ ) 1441 { 1442 AF_LatinBlue blue = &axis->blues[nn]; 1443 FT_UInt i; 1444 1445 1446 if ( !( blue->flags & AF_LATIN_BLUE_SUB_TOP ) ) 1447 continue; 1448 if ( !( blue->flags & AF_LATIN_BLUE_ACTIVE ) ) 1449 continue; 1450 1451 for ( i = 0; i < axis->blue_count; i++ ) 1452 { 1453 AF_LatinBlue b = &axis->blues[i]; 1454 1455 1456 if ( b->flags & AF_LATIN_BLUE_SUB_TOP ) 1457 continue; 1458 if ( !( b->flags & AF_LATIN_BLUE_ACTIVE ) ) 1459 continue; 1460 1461 if ( b->ref.fit <= blue->shoot.fit && 1462 b->shoot.fit >= blue->ref.fit ) 1463 { 1464 blue->flags &= ~AF_LATIN_BLUE_ACTIVE; 1465 break; 1466 } 1467 } 1468 } 1469 1470 #ifdef FT_DEBUG_LEVEL_TRACE 1471 for ( nn = 0; nn < axis->blue_count; nn++ ) 1472 { 1473 AF_LatinBlue blue = &axis->blues[nn]; 1474 1475 1476 FT_TRACE5(( " reference %d: %ld scaled to %.2f%s\n" 1477 " overshoot %d: %ld scaled to %.2f%s\n", 1478 nn, 1479 blue->ref.org, 1480 blue->ref.fit / 64.0, 1481 ( blue->flags & AF_LATIN_BLUE_ACTIVE ) ? "" 1482 : " (inactive)", 1483 nn, 1484 blue->shoot.org, 1485 blue->shoot.fit / 64.0, 1486 ( blue->flags & AF_LATIN_BLUE_ACTIVE ) ? "" 1487 : " (inactive)" )); 1488 } 1489 #endif 1490 } 1491 } 1492 1493 1494 /* Scale global values in both directions. */ 1495 1496 FT_LOCAL_DEF( void ) af_latin_metrics_scale(AF_LatinMetrics metrics,AF_Scaler scaler)1497 af_latin_metrics_scale( AF_LatinMetrics metrics, 1498 AF_Scaler scaler ) 1499 { 1500 metrics->root.scaler.render_mode = scaler->render_mode; 1501 metrics->root.scaler.face = scaler->face; 1502 metrics->root.scaler.flags = scaler->flags; 1503 1504 af_latin_metrics_scale_dim( metrics, scaler, AF_DIMENSION_HORZ ); 1505 af_latin_metrics_scale_dim( metrics, scaler, AF_DIMENSION_VERT ); 1506 } 1507 1508 1509 /* Extract standard_width from writing system/script specific */ 1510 /* metrics class. */ 1511 1512 FT_LOCAL_DEF( void ) af_latin_get_standard_widths(AF_LatinMetrics metrics,FT_Pos * stdHW,FT_Pos * stdVW)1513 af_latin_get_standard_widths( AF_LatinMetrics metrics, 1514 FT_Pos* stdHW, 1515 FT_Pos* stdVW ) 1516 { 1517 if ( stdHW ) 1518 *stdHW = metrics->axis[AF_DIMENSION_VERT].standard_width; 1519 1520 if ( stdVW ) 1521 *stdVW = metrics->axis[AF_DIMENSION_HORZ].standard_width; 1522 } 1523 1524 1525 /*************************************************************************/ 1526 /*************************************************************************/ 1527 /***** *****/ 1528 /***** L A T I N G L Y P H A N A L Y S I S *****/ 1529 /***** *****/ 1530 /*************************************************************************/ 1531 /*************************************************************************/ 1532 1533 1534 /* Walk over all contours and compute its segments. */ 1535 1536 FT_LOCAL_DEF( FT_Error ) af_latin_hints_compute_segments(AF_GlyphHints hints,AF_Dimension dim)1537 af_latin_hints_compute_segments( AF_GlyphHints hints, 1538 AF_Dimension dim ) 1539 { 1540 AF_LatinMetrics metrics = (AF_LatinMetrics)hints->metrics; 1541 AF_AxisHints axis = &hints->axis[dim]; 1542 FT_Memory memory = hints->memory; 1543 FT_Error error = FT_Err_Ok; 1544 AF_Segment segment = NULL; 1545 AF_SegmentRec seg0; 1546 AF_Point* contour = hints->contours; 1547 AF_Point* contour_limit = contour + hints->num_contours; 1548 AF_Direction major_dir, segment_dir; 1549 1550 FT_Pos flat_threshold = FLAT_THRESHOLD( metrics->units_per_em ); 1551 1552 1553 FT_ZERO( &seg0 ); 1554 seg0.score = 32000; 1555 seg0.flags = AF_EDGE_NORMAL; 1556 1557 major_dir = (AF_Direction)FT_ABS( axis->major_dir ); 1558 segment_dir = major_dir; 1559 1560 axis->num_segments = 0; 1561 1562 /* set up (u,v) in each point */ 1563 if ( dim == AF_DIMENSION_HORZ ) 1564 { 1565 AF_Point point = hints->points; 1566 AF_Point limit = point + hints->num_points; 1567 1568 1569 for ( ; point < limit; point++ ) 1570 { 1571 point->u = point->fx; 1572 point->v = point->fy; 1573 } 1574 } 1575 else 1576 { 1577 AF_Point point = hints->points; 1578 AF_Point limit = point + hints->num_points; 1579 1580 1581 for ( ; point < limit; point++ ) 1582 { 1583 point->u = point->fy; 1584 point->v = point->fx; 1585 } 1586 } 1587 1588 /* do each contour separately */ 1589 for ( ; contour < contour_limit; contour++ ) 1590 { 1591 AF_Point point = contour[0]; 1592 AF_Point last = point->prev; 1593 int on_edge = 0; 1594 1595 /* we call values measured along a segment (point->v) */ 1596 /* `coordinates', and values orthogonal to it (point->u) */ 1597 /* `positions' */ 1598 FT_Pos min_pos = 32000; 1599 FT_Pos max_pos = -32000; 1600 FT_Pos min_coord = 32000; 1601 FT_Pos max_coord = -32000; 1602 FT_UShort min_flags = AF_FLAG_NONE; 1603 FT_UShort max_flags = AF_FLAG_NONE; 1604 FT_Pos min_on_coord = 32000; 1605 FT_Pos max_on_coord = -32000; 1606 1607 FT_Bool passed; 1608 1609 AF_Segment prev_segment = NULL; 1610 1611 FT_Pos prev_min_pos = min_pos; 1612 FT_Pos prev_max_pos = max_pos; 1613 FT_Pos prev_min_coord = min_coord; 1614 FT_Pos prev_max_coord = max_coord; 1615 FT_UShort prev_min_flags = min_flags; 1616 FT_UShort prev_max_flags = max_flags; 1617 FT_Pos prev_min_on_coord = min_on_coord; 1618 FT_Pos prev_max_on_coord = max_on_coord; 1619 1620 1621 if ( FT_ABS( last->out_dir ) == major_dir && 1622 FT_ABS( point->out_dir ) == major_dir ) 1623 { 1624 /* we are already on an edge, try to locate its start */ 1625 last = point; 1626 1627 for (;;) 1628 { 1629 point = point->prev; 1630 if ( FT_ABS( point->out_dir ) != major_dir ) 1631 { 1632 point = point->next; 1633 break; 1634 } 1635 if ( point == last ) 1636 break; 1637 } 1638 } 1639 1640 last = point; 1641 passed = 0; 1642 1643 for (;;) 1644 { 1645 FT_Pos u, v; 1646 1647 1648 if ( on_edge ) 1649 { 1650 /* get minimum and maximum position */ 1651 u = point->u; 1652 if ( u < min_pos ) 1653 min_pos = u; 1654 if ( u > max_pos ) 1655 max_pos = u; 1656 1657 /* get minimum and maximum coordinate together with flags */ 1658 v = point->v; 1659 if ( v < min_coord ) 1660 { 1661 min_coord = v; 1662 min_flags = point->flags; 1663 } 1664 if ( v > max_coord ) 1665 { 1666 max_coord = v; 1667 max_flags = point->flags; 1668 } 1669 1670 /* get minimum and maximum coordinate of `on' points */ 1671 if ( !( point->flags & AF_FLAG_CONTROL ) ) 1672 { 1673 v = point->v; 1674 if ( v < min_on_coord ) 1675 min_on_coord = v; 1676 if ( v > max_on_coord ) 1677 max_on_coord = v; 1678 } 1679 1680 if ( point->out_dir != segment_dir || point == last ) 1681 { 1682 /* check whether the new segment's start point is identical to */ 1683 /* the previous segment's end point; for example, this might */ 1684 /* happen for spikes */ 1685 1686 if ( !prev_segment || segment->first != prev_segment->last ) 1687 { 1688 /* points are different: we are just leaving an edge, thus */ 1689 /* record a new segment */ 1690 1691 segment->last = point; 1692 segment->pos = (FT_Short)( ( min_pos + max_pos ) >> 1 ); 1693 segment->delta = (FT_Short)( ( max_pos - min_pos ) >> 1 ); 1694 1695 /* a segment is round if either its first or last point */ 1696 /* is a control point, and the length of the on points */ 1697 /* inbetween doesn't exceed a heuristic limit */ 1698 if ( ( min_flags | max_flags ) & AF_FLAG_CONTROL && 1699 ( max_on_coord - min_on_coord ) < flat_threshold ) 1700 segment->flags |= AF_EDGE_ROUND; 1701 1702 segment->min_coord = (FT_Short)min_coord; 1703 segment->max_coord = (FT_Short)max_coord; 1704 segment->height = segment->max_coord - segment->min_coord; 1705 1706 prev_segment = segment; 1707 prev_min_pos = min_pos; 1708 prev_max_pos = max_pos; 1709 prev_min_coord = min_coord; 1710 prev_max_coord = max_coord; 1711 prev_min_flags = min_flags; 1712 prev_max_flags = max_flags; 1713 prev_min_on_coord = min_on_coord; 1714 prev_max_on_coord = max_on_coord; 1715 } 1716 else 1717 { 1718 /* points are the same: we don't create a new segment but */ 1719 /* merge the current segment with the previous one */ 1720 1721 if ( prev_segment->last->in_dir == point->in_dir ) 1722 { 1723 /* we have identical directions (this can happen for */ 1724 /* degenerate outlines that move zig-zag along the main */ 1725 /* axis without changing the coordinate value of the other */ 1726 /* axis, and where the segments have just been merged): */ 1727 /* unify segments */ 1728 1729 /* update constraints */ 1730 1731 if ( prev_min_pos < min_pos ) 1732 min_pos = prev_min_pos; 1733 if ( prev_max_pos > max_pos ) 1734 max_pos = prev_max_pos; 1735 1736 if ( prev_min_coord < min_coord ) 1737 { 1738 min_coord = prev_min_coord; 1739 min_flags = prev_min_flags; 1740 } 1741 if ( prev_max_coord > max_coord ) 1742 { 1743 max_coord = prev_max_coord; 1744 max_flags = prev_max_flags; 1745 } 1746 1747 if ( prev_min_on_coord < min_on_coord ) 1748 min_on_coord = prev_min_on_coord; 1749 if ( prev_max_on_coord > max_on_coord ) 1750 max_on_coord = prev_max_on_coord; 1751 1752 prev_segment->last = point; 1753 prev_segment->pos = (FT_Short)( ( min_pos + 1754 max_pos ) >> 1 ); 1755 prev_segment->delta = (FT_Short)( ( max_pos - 1756 min_pos ) >> 1 ); 1757 1758 if ( ( min_flags | max_flags ) & AF_FLAG_CONTROL && 1759 ( max_on_coord - min_on_coord ) < flat_threshold ) 1760 prev_segment->flags |= AF_EDGE_ROUND; 1761 else 1762 prev_segment->flags &= ~AF_EDGE_ROUND; 1763 1764 prev_segment->min_coord = (FT_Short)min_coord; 1765 prev_segment->max_coord = (FT_Short)max_coord; 1766 prev_segment->height = prev_segment->max_coord - 1767 prev_segment->min_coord; 1768 } 1769 else 1770 { 1771 /* we have different directions; use the properties of the */ 1772 /* longer segment and discard the other one */ 1773 1774 if ( FT_ABS( prev_max_coord - prev_min_coord ) > 1775 FT_ABS( max_coord - min_coord ) ) 1776 { 1777 /* discard current segment */ 1778 1779 if ( min_pos < prev_min_pos ) 1780 prev_min_pos = min_pos; 1781 if ( max_pos > prev_max_pos ) 1782 prev_max_pos = max_pos; 1783 1784 prev_segment->last = point; 1785 prev_segment->pos = (FT_Short)( ( prev_min_pos + 1786 prev_max_pos ) >> 1 ); 1787 prev_segment->delta = (FT_Short)( ( prev_max_pos - 1788 prev_min_pos ) >> 1 ); 1789 } 1790 else 1791 { 1792 /* discard previous segment */ 1793 1794 if ( prev_min_pos < min_pos ) 1795 min_pos = prev_min_pos; 1796 if ( prev_max_pos > max_pos ) 1797 max_pos = prev_max_pos; 1798 1799 segment->last = point; 1800 segment->pos = (FT_Short)( ( min_pos + max_pos ) >> 1 ); 1801 segment->delta = (FT_Short)( ( max_pos - min_pos ) >> 1 ); 1802 1803 if ( ( min_flags | max_flags ) & AF_FLAG_CONTROL && 1804 ( max_on_coord - min_on_coord ) < flat_threshold ) 1805 segment->flags |= AF_EDGE_ROUND; 1806 1807 segment->min_coord = (FT_Short)min_coord; 1808 segment->max_coord = (FT_Short)max_coord; 1809 segment->height = segment->max_coord - 1810 segment->min_coord; 1811 1812 *prev_segment = *segment; 1813 1814 prev_min_pos = min_pos; 1815 prev_max_pos = max_pos; 1816 prev_min_coord = min_coord; 1817 prev_max_coord = max_coord; 1818 prev_min_flags = min_flags; 1819 prev_max_flags = max_flags; 1820 prev_min_on_coord = min_on_coord; 1821 prev_max_on_coord = max_on_coord; 1822 } 1823 } 1824 1825 axis->num_segments--; 1826 } 1827 1828 on_edge = 0; 1829 segment = NULL; 1830 1831 /* fall through */ 1832 } 1833 } 1834 1835 /* now exit if we are at the start/end point */ 1836 if ( point == last ) 1837 { 1838 if ( passed ) 1839 break; 1840 passed = 1; 1841 } 1842 1843 /* if we are not on an edge, check whether the major direction */ 1844 /* coincides with the current point's `out' direction, or */ 1845 /* whether we have a single-point contour */ 1846 if ( !on_edge && 1847 ( FT_ABS( point->out_dir ) == major_dir || 1848 point == point->prev ) ) 1849 { 1850 /* this is the start of a new segment! */ 1851 segment_dir = (AF_Direction)point->out_dir; 1852 1853 error = af_axis_hints_new_segment( axis, memory, &segment ); 1854 if ( error ) 1855 goto Exit; 1856 1857 /* clear all segment fields */ 1858 segment[0] = seg0; 1859 1860 segment->dir = (FT_Char)segment_dir; 1861 segment->first = point; 1862 segment->last = point; 1863 1864 /* `af_axis_hints_new_segment' reallocates memory, */ 1865 /* thus we have to refresh the `prev_segment' pointer */ 1866 if ( prev_segment ) 1867 prev_segment = segment - 1; 1868 1869 min_pos = max_pos = point->u; 1870 min_coord = max_coord = point->v; 1871 min_flags = max_flags = point->flags; 1872 1873 if ( point->flags & AF_FLAG_CONTROL ) 1874 { 1875 min_on_coord = 32000; 1876 max_on_coord = -32000; 1877 } 1878 else 1879 min_on_coord = max_on_coord = point->v; 1880 1881 on_edge = 1; 1882 1883 if ( point == point->prev ) 1884 { 1885 /* we have a one-point segment: this is a one-point */ 1886 /* contour with `in' and `out' direction set to */ 1887 /* AF_DIR_NONE */ 1888 segment->pos = (FT_Short)min_pos; 1889 1890 if (point->flags & AF_FLAG_CONTROL) 1891 segment->flags |= AF_EDGE_ROUND; 1892 1893 segment->min_coord = (FT_Short)point->v; 1894 segment->max_coord = (FT_Short)point->v; 1895 segment->height = 0; 1896 1897 on_edge = 0; 1898 segment = NULL; 1899 } 1900 } 1901 1902 point = point->next; 1903 } 1904 1905 } /* contours */ 1906 1907 1908 /* now slightly increase the height of segments if this makes */ 1909 /* sense -- this is used to better detect and ignore serifs */ 1910 { 1911 AF_Segment segments = axis->segments; 1912 AF_Segment segments_end = FT_OFFSET( segments, axis->num_segments ); 1913 1914 1915 for ( segment = segments; segment < segments_end; segment++ ) 1916 { 1917 AF_Point first = segment->first; 1918 AF_Point last = segment->last; 1919 FT_Pos first_v = first->v; 1920 FT_Pos last_v = last->v; 1921 1922 1923 if ( first_v < last_v ) 1924 { 1925 AF_Point p; 1926 1927 1928 p = first->prev; 1929 if ( p->v < first_v ) 1930 segment->height = (FT_Short)( segment->height + 1931 ( ( first_v - p->v ) >> 1 ) ); 1932 1933 p = last->next; 1934 if ( p->v > last_v ) 1935 segment->height = (FT_Short)( segment->height + 1936 ( ( p->v - last_v ) >> 1 ) ); 1937 } 1938 else 1939 { 1940 AF_Point p; 1941 1942 1943 p = first->prev; 1944 if ( p->v > first_v ) 1945 segment->height = (FT_Short)( segment->height + 1946 ( ( p->v - first_v ) >> 1 ) ); 1947 1948 p = last->next; 1949 if ( p->v < last_v ) 1950 segment->height = (FT_Short)( segment->height + 1951 ( ( last_v - p->v ) >> 1 ) ); 1952 } 1953 } 1954 } 1955 1956 Exit: 1957 return error; 1958 } 1959 1960 1961 /* Link segments to form stems and serifs. If `width_count' and */ 1962 /* `widths' are non-zero, use them to fine-tune the scoring function. */ 1963 1964 FT_LOCAL_DEF( void ) af_latin_hints_link_segments(AF_GlyphHints hints,FT_UInt width_count,AF_WidthRec * widths,AF_Dimension dim)1965 af_latin_hints_link_segments( AF_GlyphHints hints, 1966 FT_UInt width_count, 1967 AF_WidthRec* widths, 1968 AF_Dimension dim ) 1969 { 1970 AF_AxisHints axis = &hints->axis[dim]; 1971 AF_Segment segments = axis->segments; 1972 AF_Segment segment_limit = segments + axis->num_segments; 1973 FT_Pos len_threshold, len_score, dist_score, max_width; 1974 AF_Segment seg1, seg2; 1975 1976 1977 if ( width_count ) 1978 max_width = widths[width_count - 1].org; 1979 else 1980 max_width = 0; 1981 1982 /* a heuristic value to set up a minimum value for overlapping */ 1983 len_threshold = AF_LATIN_CONSTANT( hints->metrics, 8 ); 1984 if ( len_threshold == 0 ) 1985 len_threshold = 1; 1986 1987 /* a heuristic value to weight lengths */ 1988 len_score = AF_LATIN_CONSTANT( hints->metrics, 6000 ); 1989 1990 /* a heuristic value to weight distances (no call to */ 1991 /* AF_LATIN_CONSTANT needed, since we work on multiples */ 1992 /* of the stem width) */ 1993 dist_score = 3000; 1994 1995 /* now compare each segment to the others */ 1996 for ( seg1 = segments; seg1 < segment_limit; seg1++ ) 1997 { 1998 if ( seg1->dir != axis->major_dir ) 1999 continue; 2000 2001 /* search for stems having opposite directions, */ 2002 /* with seg1 to the `left' of seg2 */ 2003 for ( seg2 = segments; seg2 < segment_limit; seg2++ ) 2004 { 2005 FT_Pos pos1 = seg1->pos; 2006 FT_Pos pos2 = seg2->pos; 2007 2008 2009 if ( seg1->dir + seg2->dir == 0 && pos2 > pos1 ) 2010 { 2011 /* compute distance between the two segments */ 2012 FT_Pos min = seg1->min_coord; 2013 FT_Pos max = seg1->max_coord; 2014 FT_Pos len; 2015 2016 2017 if ( min < seg2->min_coord ) 2018 min = seg2->min_coord; 2019 2020 if ( max > seg2->max_coord ) 2021 max = seg2->max_coord; 2022 2023 /* compute maximum coordinate difference of the two segments */ 2024 /* (this is, how much they overlap) */ 2025 len = max - min; 2026 if ( len >= len_threshold ) 2027 { 2028 /* 2029 * The score is the sum of two demerits indicating the 2030 * `badness' of a fit, measured along the segments' main axis 2031 * and orthogonal to it, respectively. 2032 * 2033 * - The less overlapping along the main axis, the worse it 2034 * is, causing a larger demerit. 2035 * 2036 * - The nearer the orthogonal distance to a stem width, the 2037 * better it is, causing a smaller demerit. For simplicity, 2038 * however, we only increase the demerit for values that 2039 * exceed the largest stem width. 2040 */ 2041 2042 FT_Pos dist = pos2 - pos1; 2043 2044 FT_Pos dist_demerit, score; 2045 2046 2047 if ( max_width ) 2048 { 2049 /* distance demerits are based on multiples of `max_width'; */ 2050 /* we scale by 1024 for getting more precision */ 2051 FT_Pos delta = ( dist << 10 ) / max_width - ( 1 << 10 ); 2052 2053 2054 if ( delta > 10000 ) 2055 dist_demerit = 32000; 2056 else if ( delta > 0 ) 2057 dist_demerit = delta * delta / dist_score; 2058 else 2059 dist_demerit = 0; 2060 } 2061 else 2062 dist_demerit = dist; /* default if no widths available */ 2063 2064 score = dist_demerit + len_score / len; 2065 2066 /* and we search for the smallest score */ 2067 if ( score < seg1->score ) 2068 { 2069 seg1->score = score; 2070 seg1->link = seg2; 2071 } 2072 2073 if ( score < seg2->score ) 2074 { 2075 seg2->score = score; 2076 seg2->link = seg1; 2077 } 2078 } 2079 } 2080 } 2081 } 2082 2083 /* now compute the `serif' segments, cf. explanations in `afhints.h' */ 2084 for ( seg1 = segments; seg1 < segment_limit; seg1++ ) 2085 { 2086 seg2 = seg1->link; 2087 2088 if ( seg2 ) 2089 { 2090 if ( seg2->link != seg1 ) 2091 { 2092 seg1->link = 0; 2093 seg1->serif = seg2->link; 2094 } 2095 } 2096 } 2097 } 2098 2099 2100 /* Link segments to edges, using feature analysis for selection. */ 2101 2102 FT_LOCAL_DEF( FT_Error ) af_latin_hints_compute_edges(AF_GlyphHints hints,AF_Dimension dim)2103 af_latin_hints_compute_edges( AF_GlyphHints hints, 2104 AF_Dimension dim ) 2105 { 2106 AF_AxisHints axis = &hints->axis[dim]; 2107 FT_Error error = FT_Err_Ok; 2108 FT_Memory memory = hints->memory; 2109 AF_LatinAxis laxis = &((AF_LatinMetrics)hints->metrics)->axis[dim]; 2110 2111 AF_StyleClass style_class = hints->metrics->style_class; 2112 AF_ScriptClass script_class = af_script_classes[style_class->script]; 2113 2114 FT_Bool top_to_bottom_hinting = 0; 2115 2116 AF_Segment segments = axis->segments; 2117 AF_Segment segment_limit = segments + axis->num_segments; 2118 AF_Segment seg; 2119 2120 #if 0 2121 AF_Direction up_dir; 2122 #endif 2123 FT_Fixed scale; 2124 FT_Pos edge_distance_threshold; 2125 FT_Pos segment_length_threshold; 2126 FT_Pos segment_width_threshold; 2127 2128 2129 axis->num_edges = 0; 2130 2131 scale = ( dim == AF_DIMENSION_HORZ ) ? hints->x_scale 2132 : hints->y_scale; 2133 2134 #if 0 2135 up_dir = ( dim == AF_DIMENSION_HORZ ) ? AF_DIR_UP 2136 : AF_DIR_RIGHT; 2137 #endif 2138 2139 if ( dim == AF_DIMENSION_VERT ) 2140 top_to_bottom_hinting = script_class->top_to_bottom_hinting; 2141 2142 /* 2143 * We ignore all segments that are less than 1 pixel in length 2144 * to avoid many problems with serif fonts. We compute the 2145 * corresponding threshold in font units. 2146 */ 2147 if ( dim == AF_DIMENSION_HORZ ) 2148 segment_length_threshold = FT_DivFix( 64, hints->y_scale ); 2149 else 2150 segment_length_threshold = 0; 2151 2152 /* 2153 * Similarly, we ignore segments that have a width delta 2154 * larger than 0.5px (i.e., a width larger than 1px). 2155 */ 2156 segment_width_threshold = FT_DivFix( 32, scale ); 2157 2158 /********************************************************************** 2159 * 2160 * We begin by generating a sorted table of edges for the current 2161 * direction. To do so, we simply scan each segment and try to find 2162 * an edge in our table that corresponds to its position. 2163 * 2164 * If no edge is found, we create and insert a new edge in the 2165 * sorted table. Otherwise, we simply add the segment to the edge's 2166 * list which gets processed in the second step to compute the 2167 * edge's properties. 2168 * 2169 * Note that the table of edges is sorted along the segment/edge 2170 * position. 2171 * 2172 */ 2173 2174 /* assure that edge distance threshold is at most 0.25px */ 2175 edge_distance_threshold = FT_MulFix( laxis->edge_distance_threshold, 2176 scale ); 2177 if ( edge_distance_threshold > 64 / 4 ) 2178 edge_distance_threshold = 64 / 4; 2179 2180 edge_distance_threshold = FT_DivFix( edge_distance_threshold, 2181 scale ); 2182 2183 for ( seg = segments; seg < segment_limit; seg++ ) 2184 { 2185 AF_Edge found = NULL; 2186 FT_Int ee; 2187 2188 2189 /* ignore too short segments, too wide ones, and, in this loop, */ 2190 /* one-point segments without a direction */ 2191 if ( seg->height < segment_length_threshold || 2192 seg->delta > segment_width_threshold || 2193 seg->dir == AF_DIR_NONE ) 2194 continue; 2195 2196 /* A special case for serif edges: If they are smaller than */ 2197 /* 1.5 pixels we ignore them. */ 2198 if ( seg->serif && 2199 2 * seg->height < 3 * segment_length_threshold ) 2200 continue; 2201 2202 /* look for an edge corresponding to the segment */ 2203 for ( ee = 0; ee < axis->num_edges; ee++ ) 2204 { 2205 AF_Edge edge = axis->edges + ee; 2206 FT_Pos dist; 2207 2208 2209 dist = seg->pos - edge->fpos; 2210 if ( dist < 0 ) 2211 dist = -dist; 2212 2213 if ( dist < edge_distance_threshold && edge->dir == seg->dir ) 2214 { 2215 found = edge; 2216 break; 2217 } 2218 } 2219 2220 if ( !found ) 2221 { 2222 AF_Edge edge; 2223 2224 2225 /* insert a new edge in the list and */ 2226 /* sort according to the position */ 2227 error = af_axis_hints_new_edge( axis, seg->pos, 2228 (AF_Direction)seg->dir, 2229 top_to_bottom_hinting, 2230 memory, &edge ); 2231 if ( error ) 2232 goto Exit; 2233 2234 /* add the segment to the new edge's list */ 2235 FT_ZERO( edge ); 2236 2237 edge->first = seg; 2238 edge->last = seg; 2239 edge->dir = seg->dir; 2240 edge->fpos = seg->pos; 2241 edge->opos = FT_MulFix( seg->pos, scale ); 2242 edge->pos = edge->opos; 2243 seg->edge_next = seg; 2244 } 2245 else 2246 { 2247 /* if an edge was found, simply add the segment to the edge's */ 2248 /* list */ 2249 seg->edge_next = found->first; 2250 found->last->edge_next = seg; 2251 found->last = seg; 2252 } 2253 } 2254 2255 /* we loop again over all segments to catch one-point segments */ 2256 /* without a direction: if possible, link them to existing edges */ 2257 for ( seg = segments; seg < segment_limit; seg++ ) 2258 { 2259 AF_Edge found = NULL; 2260 FT_Int ee; 2261 2262 2263 if ( seg->dir != AF_DIR_NONE ) 2264 continue; 2265 2266 /* look for an edge corresponding to the segment */ 2267 for ( ee = 0; ee < axis->num_edges; ee++ ) 2268 { 2269 AF_Edge edge = axis->edges + ee; 2270 FT_Pos dist; 2271 2272 2273 dist = seg->pos - edge->fpos; 2274 if ( dist < 0 ) 2275 dist = -dist; 2276 2277 if ( dist < edge_distance_threshold ) 2278 { 2279 found = edge; 2280 break; 2281 } 2282 } 2283 2284 /* one-point segments without a match are ignored */ 2285 if ( found ) 2286 { 2287 seg->edge_next = found->first; 2288 found->last->edge_next = seg; 2289 found->last = seg; 2290 } 2291 } 2292 2293 2294 /******************************************************************* 2295 * 2296 * Good, we now compute each edge's properties according to the 2297 * segments found on its position. Basically, these are 2298 * 2299 * - the edge's main direction 2300 * - stem edge, serif edge or both (which defaults to stem then) 2301 * - rounded edge, straight or both (which defaults to straight) 2302 * - link for edge 2303 * 2304 */ 2305 2306 /* first of all, set the `edge' field in each segment -- this is */ 2307 /* required in order to compute edge links */ 2308 2309 /* 2310 * Note that removing this loop and setting the `edge' field of each 2311 * segment directly in the code above slows down execution speed for 2312 * some reasons on platforms like the Sun. 2313 */ 2314 { 2315 AF_Edge edges = axis->edges; 2316 AF_Edge edge_limit = FT_OFFSET( edges, axis->num_edges ); 2317 AF_Edge edge; 2318 2319 2320 for ( edge = edges; edge < edge_limit; edge++ ) 2321 { 2322 seg = edge->first; 2323 if ( seg ) 2324 do 2325 { 2326 seg->edge = edge; 2327 seg = seg->edge_next; 2328 2329 } while ( seg != edge->first ); 2330 } 2331 2332 /* now compute each edge properties */ 2333 for ( edge = edges; edge < edge_limit; edge++ ) 2334 { 2335 FT_Int is_round = 0; /* does it contain round segments? */ 2336 FT_Int is_straight = 0; /* does it contain straight segments? */ 2337 #if 0 2338 FT_Pos ups = 0; /* number of upwards segments */ 2339 FT_Pos downs = 0; /* number of downwards segments */ 2340 #endif 2341 2342 2343 seg = edge->first; 2344 2345 do 2346 { 2347 FT_Bool is_serif; 2348 2349 2350 /* check for roundness of segment */ 2351 if ( seg->flags & AF_EDGE_ROUND ) 2352 is_round++; 2353 else 2354 is_straight++; 2355 2356 #if 0 2357 /* check for segment direction */ 2358 if ( seg->dir == up_dir ) 2359 ups += seg->max_coord - seg->min_coord; 2360 else 2361 downs += seg->max_coord - seg->min_coord; 2362 #endif 2363 2364 /* check for links -- if seg->serif is set, then seg->link must */ 2365 /* be ignored */ 2366 is_serif = FT_BOOL( seg->serif && 2367 seg->serif->edge && 2368 seg->serif->edge != edge ); 2369 2370 if ( ( seg->link && seg->link->edge ) || is_serif ) 2371 { 2372 AF_Edge edge2; 2373 AF_Segment seg2; 2374 2375 2376 edge2 = edge->link; 2377 seg2 = seg->link; 2378 2379 if ( is_serif ) 2380 { 2381 seg2 = seg->serif; 2382 edge2 = edge->serif; 2383 } 2384 2385 if ( edge2 ) 2386 { 2387 FT_Pos edge_delta; 2388 FT_Pos seg_delta; 2389 2390 2391 edge_delta = edge->fpos - edge2->fpos; 2392 if ( edge_delta < 0 ) 2393 edge_delta = -edge_delta; 2394 2395 seg_delta = seg->pos - seg2->pos; 2396 if ( seg_delta < 0 ) 2397 seg_delta = -seg_delta; 2398 2399 if ( seg_delta < edge_delta ) 2400 edge2 = seg2->edge; 2401 } 2402 else 2403 edge2 = seg2->edge; 2404 2405 if ( is_serif ) 2406 { 2407 edge->serif = edge2; 2408 edge2->flags |= AF_EDGE_SERIF; 2409 } 2410 else 2411 edge->link = edge2; 2412 } 2413 2414 seg = seg->edge_next; 2415 2416 } while ( seg != edge->first ); 2417 2418 /* set the round/straight flags */ 2419 edge->flags = AF_EDGE_NORMAL; 2420 2421 if ( is_round > 0 && is_round >= is_straight ) 2422 edge->flags |= AF_EDGE_ROUND; 2423 2424 #if 0 2425 /* set the edge's main direction */ 2426 edge->dir = AF_DIR_NONE; 2427 2428 if ( ups > downs ) 2429 edge->dir = (FT_Char)up_dir; 2430 2431 else if ( ups < downs ) 2432 edge->dir = (FT_Char)-up_dir; 2433 2434 else if ( ups == downs ) 2435 edge->dir = 0; /* both up and down! */ 2436 #endif 2437 2438 /* get rid of serifs if link is set */ 2439 /* XXX: This gets rid of many unpleasant artefacts! */ 2440 /* Example: the `c' in cour.pfa at size 13 */ 2441 2442 if ( edge->serif && edge->link ) 2443 edge->serif = NULL; 2444 } 2445 } 2446 2447 Exit: 2448 return error; 2449 } 2450 2451 2452 /* Detect segments and edges for given dimension. */ 2453 2454 FT_LOCAL_DEF( FT_Error ) af_latin_hints_detect_features(AF_GlyphHints hints,FT_UInt width_count,AF_WidthRec * widths,AF_Dimension dim)2455 af_latin_hints_detect_features( AF_GlyphHints hints, 2456 FT_UInt width_count, 2457 AF_WidthRec* widths, 2458 AF_Dimension dim ) 2459 { 2460 FT_Error error; 2461 2462 2463 error = af_latin_hints_compute_segments( hints, dim ); 2464 if ( !error ) 2465 { 2466 af_latin_hints_link_segments( hints, width_count, widths, dim ); 2467 2468 error = af_latin_hints_compute_edges( hints, dim ); 2469 } 2470 2471 return error; 2472 } 2473 2474 2475 /* Compute all edges which lie within blue zones. */ 2476 2477 static void af_latin_hints_compute_blue_edges(AF_GlyphHints hints,AF_LatinMetrics metrics)2478 af_latin_hints_compute_blue_edges( AF_GlyphHints hints, 2479 AF_LatinMetrics metrics ) 2480 { 2481 AF_AxisHints axis = &hints->axis[AF_DIMENSION_VERT]; 2482 AF_Edge edge = axis->edges; 2483 AF_Edge edge_limit = edge + axis->num_edges; 2484 AF_LatinAxis latin = &metrics->axis[AF_DIMENSION_VERT]; 2485 FT_Fixed scale = latin->scale; 2486 2487 2488 /* compute which blue zones are active, i.e. have their scaled */ 2489 /* size < 3/4 pixels */ 2490 2491 /* for each horizontal edge search the blue zone which is closest */ 2492 for ( ; edge < edge_limit; edge++ ) 2493 { 2494 FT_UInt bb; 2495 AF_Width best_blue = NULL; 2496 FT_Bool best_blue_is_neutral = 0; 2497 FT_Pos best_dist; /* initial threshold */ 2498 2499 2500 /* compute the initial threshold as a fraction of the EM size */ 2501 /* (the value 40 is heuristic) */ 2502 best_dist = FT_MulFix( metrics->units_per_em / 40, scale ); 2503 2504 /* assure a minimum distance of 0.5px */ 2505 if ( best_dist > 64 / 2 ) 2506 best_dist = 64 / 2; 2507 2508 for ( bb = 0; bb < latin->blue_count; bb++ ) 2509 { 2510 AF_LatinBlue blue = latin->blues + bb; 2511 FT_Bool is_top_blue, is_neutral_blue, is_major_dir; 2512 2513 2514 /* skip inactive blue zones (i.e., those that are too large) */ 2515 if ( !( blue->flags & AF_LATIN_BLUE_ACTIVE ) ) 2516 continue; 2517 2518 /* if it is a top zone, check for right edges (against the major */ 2519 /* direction); if it is a bottom zone, check for left edges (in */ 2520 /* the major direction) -- this assumes the TrueType convention */ 2521 /* for the orientation of contours */ 2522 is_top_blue = 2523 (FT_Byte)( ( blue->flags & ( AF_LATIN_BLUE_TOP | 2524 AF_LATIN_BLUE_SUB_TOP ) ) != 0 ); 2525 is_neutral_blue = 2526 (FT_Byte)( ( blue->flags & AF_LATIN_BLUE_NEUTRAL ) != 0); 2527 is_major_dir = 2528 FT_BOOL( edge->dir == axis->major_dir ); 2529 2530 /* neutral blue zones are handled for both directions */ 2531 if ( is_top_blue ^ is_major_dir || is_neutral_blue ) 2532 { 2533 FT_Pos dist; 2534 2535 2536 /* first of all, compare it to the reference position */ 2537 dist = edge->fpos - blue->ref.org; 2538 if ( dist < 0 ) 2539 dist = -dist; 2540 2541 dist = FT_MulFix( dist, scale ); 2542 if ( dist < best_dist ) 2543 { 2544 best_dist = dist; 2545 best_blue = &blue->ref; 2546 best_blue_is_neutral = is_neutral_blue; 2547 } 2548 2549 /* now compare it to the overshoot position and check whether */ 2550 /* the edge is rounded, and whether the edge is over the */ 2551 /* reference position of a top zone, or under the reference */ 2552 /* position of a bottom zone (provided we don't have a */ 2553 /* neutral blue zone) */ 2554 if ( edge->flags & AF_EDGE_ROUND && 2555 dist != 0 && 2556 !is_neutral_blue ) 2557 { 2558 FT_Bool is_under_ref = FT_BOOL( edge->fpos < blue->ref.org ); 2559 2560 2561 if ( is_top_blue ^ is_under_ref ) 2562 { 2563 dist = edge->fpos - blue->shoot.org; 2564 if ( dist < 0 ) 2565 dist = -dist; 2566 2567 dist = FT_MulFix( dist, scale ); 2568 if ( dist < best_dist ) 2569 { 2570 best_dist = dist; 2571 best_blue = &blue->shoot; 2572 best_blue_is_neutral = is_neutral_blue; 2573 } 2574 } 2575 } 2576 } 2577 } 2578 2579 if ( best_blue ) 2580 { 2581 edge->blue_edge = best_blue; 2582 if ( best_blue_is_neutral ) 2583 edge->flags |= AF_EDGE_NEUTRAL; 2584 } 2585 } 2586 } 2587 2588 2589 /* Initalize hinting engine. */ 2590 2591 static FT_Error af_latin_hints_init(AF_GlyphHints hints,AF_LatinMetrics metrics)2592 af_latin_hints_init( AF_GlyphHints hints, 2593 AF_LatinMetrics metrics ) 2594 { 2595 FT_Render_Mode mode; 2596 FT_UInt32 scaler_flags, other_flags; 2597 FT_Face face = metrics->root.scaler.face; 2598 2599 2600 af_glyph_hints_rescale( hints, (AF_StyleMetrics)metrics ); 2601 2602 /* 2603 * correct x_scale and y_scale if needed, since they may have 2604 * been modified by `af_latin_metrics_scale_dim' above 2605 */ 2606 hints->x_scale = metrics->axis[AF_DIMENSION_HORZ].scale; 2607 hints->x_delta = metrics->axis[AF_DIMENSION_HORZ].delta; 2608 hints->y_scale = metrics->axis[AF_DIMENSION_VERT].scale; 2609 hints->y_delta = metrics->axis[AF_DIMENSION_VERT].delta; 2610 2611 /* compute flags depending on render mode, etc. */ 2612 mode = metrics->root.scaler.render_mode; 2613 2614 #if 0 /* #ifdef AF_CONFIG_OPTION_USE_WARPER */ 2615 if ( mode == FT_RENDER_MODE_LCD || mode == FT_RENDER_MODE_LCD_V ) 2616 metrics->root.scaler.render_mode = mode = FT_RENDER_MODE_NORMAL; 2617 #endif 2618 2619 scaler_flags = hints->scaler_flags; 2620 other_flags = 0; 2621 2622 /* 2623 * We snap the width of vertical stems for the monochrome and 2624 * horizontal LCD rendering targets only. 2625 */ 2626 if ( mode == FT_RENDER_MODE_MONO || mode == FT_RENDER_MODE_LCD ) 2627 other_flags |= AF_LATIN_HINTS_HORZ_SNAP; 2628 2629 /* 2630 * We snap the width of horizontal stems for the monochrome and 2631 * vertical LCD rendering targets only. 2632 */ 2633 if ( mode == FT_RENDER_MODE_MONO || mode == FT_RENDER_MODE_LCD_V ) 2634 other_flags |= AF_LATIN_HINTS_VERT_SNAP; 2635 2636 /* 2637 * We adjust stems to full pixels unless in `light' or `lcd' mode. 2638 */ 2639 if ( mode != FT_RENDER_MODE_LIGHT && mode != FT_RENDER_MODE_LCD ) 2640 other_flags |= AF_LATIN_HINTS_STEM_ADJUST; 2641 2642 if ( mode == FT_RENDER_MODE_MONO ) 2643 other_flags |= AF_LATIN_HINTS_MONO; 2644 2645 /* 2646 * In `light' or `lcd' mode we disable horizontal hinting completely. 2647 * We also do it if the face is italic. 2648 * 2649 * However, if warping is enabled (which only works in `light' hinting 2650 * mode), advance widths get adjusted, too. 2651 */ 2652 if ( mode == FT_RENDER_MODE_LIGHT || mode == FT_RENDER_MODE_LCD || 2653 ( face->style_flags & FT_STYLE_FLAG_ITALIC ) != 0 ) 2654 scaler_flags |= AF_SCALER_FLAG_NO_HORIZONTAL; 2655 2656 #ifdef AF_CONFIG_OPTION_USE_WARPER 2657 /* get (global) warper flag */ 2658 if ( !metrics->root.globals->module->warping ) 2659 scaler_flags |= AF_SCALER_FLAG_NO_WARPER; 2660 #endif 2661 2662 hints->scaler_flags = scaler_flags; 2663 hints->other_flags = other_flags; 2664 2665 return FT_Err_Ok; 2666 } 2667 2668 2669 /*************************************************************************/ 2670 /*************************************************************************/ 2671 /***** *****/ 2672 /***** L A T I N G L Y P H G R I D - F I T T I N G *****/ 2673 /***** *****/ 2674 /*************************************************************************/ 2675 /*************************************************************************/ 2676 2677 /* Snap a given width in scaled coordinates to one of the */ 2678 /* current standard widths. */ 2679 2680 static FT_Pos af_latin_snap_width(AF_Width widths,FT_UInt count,FT_Pos width)2681 af_latin_snap_width( AF_Width widths, 2682 FT_UInt count, 2683 FT_Pos width ) 2684 { 2685 FT_UInt n; 2686 FT_Pos best = 64 + 32 + 2; 2687 FT_Pos reference = width; 2688 FT_Pos scaled; 2689 2690 2691 for ( n = 0; n < count; n++ ) 2692 { 2693 FT_Pos w; 2694 FT_Pos dist; 2695 2696 2697 w = widths[n].cur; 2698 dist = width - w; 2699 if ( dist < 0 ) 2700 dist = -dist; 2701 if ( dist < best ) 2702 { 2703 best = dist; 2704 reference = w; 2705 } 2706 } 2707 2708 scaled = FT_PIX_ROUND( reference ); 2709 2710 if ( width >= reference ) 2711 { 2712 if ( width < scaled + 48 ) 2713 width = reference; 2714 } 2715 else 2716 { 2717 if ( width > scaled - 48 ) 2718 width = reference; 2719 } 2720 2721 return width; 2722 } 2723 2724 2725 /* Compute the snapped width of a given stem, ignoring very thin ones. */ 2726 /* There is a lot of voodoo in this function; changing the hard-coded */ 2727 /* parameters influence the whole hinting process. */ 2728 2729 static FT_Pos af_latin_compute_stem_width(AF_GlyphHints hints,AF_Dimension dim,FT_Pos width,FT_Pos base_delta,FT_UInt base_flags,FT_UInt stem_flags)2730 af_latin_compute_stem_width( AF_GlyphHints hints, 2731 AF_Dimension dim, 2732 FT_Pos width, 2733 FT_Pos base_delta, 2734 FT_UInt base_flags, 2735 FT_UInt stem_flags ) 2736 { 2737 AF_LatinMetrics metrics = (AF_LatinMetrics)hints->metrics; 2738 AF_LatinAxis axis = &metrics->axis[dim]; 2739 FT_Pos dist = width; 2740 FT_Int sign = 0; 2741 FT_Int vertical = ( dim == AF_DIMENSION_VERT ); 2742 2743 2744 if ( !AF_LATIN_HINTS_DO_STEM_ADJUST( hints ) || 2745 axis->extra_light ) 2746 return width; 2747 2748 if ( dist < 0 ) 2749 { 2750 dist = -width; 2751 sign = 1; 2752 } 2753 2754 if ( ( vertical && !AF_LATIN_HINTS_DO_VERT_SNAP( hints ) ) || 2755 ( !vertical && !AF_LATIN_HINTS_DO_HORZ_SNAP( hints ) ) ) 2756 { 2757 /* smooth hinting process: very lightly quantize the stem width */ 2758 2759 /* leave the widths of serifs alone */ 2760 if ( ( stem_flags & AF_EDGE_SERIF ) && 2761 vertical && 2762 ( dist < 3 * 64 ) ) 2763 goto Done_Width; 2764 2765 else if ( base_flags & AF_EDGE_ROUND ) 2766 { 2767 if ( dist < 80 ) 2768 dist = 64; 2769 } 2770 else if ( dist < 56 ) 2771 dist = 56; 2772 2773 if ( axis->width_count > 0 ) 2774 { 2775 FT_Pos delta; 2776 2777 2778 /* compare to standard width */ 2779 delta = dist - axis->widths[0].cur; 2780 2781 if ( delta < 0 ) 2782 delta = -delta; 2783 2784 if ( delta < 40 ) 2785 { 2786 dist = axis->widths[0].cur; 2787 if ( dist < 48 ) 2788 dist = 48; 2789 2790 goto Done_Width; 2791 } 2792 2793 if ( dist < 3 * 64 ) 2794 { 2795 delta = dist & 63; 2796 dist &= -64; 2797 2798 if ( delta < 10 ) 2799 dist += delta; 2800 2801 else if ( delta < 32 ) 2802 dist += 10; 2803 2804 else if ( delta < 54 ) 2805 dist += 54; 2806 2807 else 2808 dist += delta; 2809 } 2810 else 2811 { 2812 /* A stem's end position depends on two values: the start */ 2813 /* position and the stem length. The former gets usually */ 2814 /* rounded to the grid, while the latter gets rounded also if it */ 2815 /* exceeds a certain length (see below in this function). This */ 2816 /* `double rounding' can lead to a great difference to the */ 2817 /* original, unhinted position; this normally doesn't matter for */ 2818 /* large PPEM values, but for small sizes it can easily make */ 2819 /* outlines collide. For this reason, we adjust the stem length */ 2820 /* by a small amount depending on the PPEM value in case the */ 2821 /* former and latter rounding both point into the same */ 2822 /* direction. */ 2823 2824 FT_Pos bdelta = 0; 2825 2826 2827 if ( ( ( width > 0 ) && ( base_delta > 0 ) ) || 2828 ( ( width < 0 ) && ( base_delta < 0 ) ) ) 2829 { 2830 FT_UInt ppem = metrics->root.scaler.face->size->metrics.x_ppem; 2831 2832 2833 if ( ppem < 10 ) 2834 bdelta = base_delta; 2835 else if ( ppem < 30 ) 2836 bdelta = ( base_delta * (FT_Pos)( 30 - ppem ) ) / 20; 2837 2838 if ( bdelta < 0 ) 2839 bdelta = -bdelta; 2840 } 2841 2842 dist = ( dist - bdelta + 32 ) & ~63; 2843 } 2844 } 2845 } 2846 else 2847 { 2848 /* strong hinting process: snap the stem width to integer pixels */ 2849 2850 FT_Pos org_dist = dist; 2851 2852 2853 dist = af_latin_snap_width( axis->widths, axis->width_count, dist ); 2854 2855 if ( vertical ) 2856 { 2857 /* in the case of vertical hinting, always round */ 2858 /* the stem heights to integer pixels */ 2859 2860 if ( dist >= 64 ) 2861 dist = ( dist + 16 ) & ~63; 2862 else 2863 dist = 64; 2864 } 2865 else 2866 { 2867 if ( AF_LATIN_HINTS_DO_MONO( hints ) ) 2868 { 2869 /* monochrome horizontal hinting: snap widths to integer pixels */ 2870 /* with a different threshold */ 2871 2872 if ( dist < 64 ) 2873 dist = 64; 2874 else 2875 dist = ( dist + 32 ) & ~63; 2876 } 2877 else 2878 { 2879 /* for horizontal anti-aliased hinting, we adopt a more subtle */ 2880 /* approach: we strengthen small stems, round stems whose size */ 2881 /* is between 1 and 2 pixels to an integer, otherwise nothing */ 2882 2883 if ( dist < 48 ) 2884 dist = ( dist + 64 ) >> 1; 2885 2886 else if ( dist < 128 ) 2887 { 2888 /* We only round to an integer width if the corresponding */ 2889 /* distortion is less than 1/4 pixel. Otherwise this */ 2890 /* makes everything worse since the diagonals, which are */ 2891 /* not hinted, appear a lot bolder or thinner than the */ 2892 /* vertical stems. */ 2893 2894 FT_Pos delta; 2895 2896 2897 dist = ( dist + 22 ) & ~63; 2898 delta = dist - org_dist; 2899 if ( delta < 0 ) 2900 delta = -delta; 2901 2902 if ( delta >= 16 ) 2903 { 2904 dist = org_dist; 2905 if ( dist < 48 ) 2906 dist = ( dist + 64 ) >> 1; 2907 } 2908 } 2909 else 2910 /* round otherwise to prevent color fringes in LCD mode */ 2911 dist = ( dist + 32 ) & ~63; 2912 } 2913 } 2914 } 2915 2916 Done_Width: 2917 if ( sign ) 2918 dist = -dist; 2919 2920 return dist; 2921 } 2922 2923 2924 /* Align one stem edge relative to the previous stem edge. */ 2925 2926 static void af_latin_align_linked_edge(AF_GlyphHints hints,AF_Dimension dim,AF_Edge base_edge,AF_Edge stem_edge)2927 af_latin_align_linked_edge( AF_GlyphHints hints, 2928 AF_Dimension dim, 2929 AF_Edge base_edge, 2930 AF_Edge stem_edge ) 2931 { 2932 FT_Pos dist, base_delta; 2933 FT_Pos fitted_width; 2934 2935 2936 dist = stem_edge->opos - base_edge->opos; 2937 base_delta = base_edge->pos - base_edge->opos; 2938 2939 fitted_width = af_latin_compute_stem_width( hints, dim, 2940 dist, base_delta, 2941 base_edge->flags, 2942 stem_edge->flags ); 2943 2944 2945 stem_edge->pos = base_edge->pos + fitted_width; 2946 2947 FT_TRACE5(( " LINK: edge %ld (opos=%.2f) linked to %.2f," 2948 " dist was %.2f, now %.2f\n", 2949 stem_edge - hints->axis[dim].edges, stem_edge->opos / 64.0, 2950 stem_edge->pos / 64.0, dist / 64.0, fitted_width / 64.0 )); 2951 } 2952 2953 2954 /* Shift the coordinates of the `serif' edge by the same amount */ 2955 /* as the corresponding `base' edge has been moved already. */ 2956 2957 static void af_latin_align_serif_edge(AF_GlyphHints hints,AF_Edge base,AF_Edge serif)2958 af_latin_align_serif_edge( AF_GlyphHints hints, 2959 AF_Edge base, 2960 AF_Edge serif ) 2961 { 2962 FT_UNUSED( hints ); 2963 2964 serif->pos = base->pos + ( serif->opos - base->opos ); 2965 } 2966 2967 2968 /*************************************************************************/ 2969 /*************************************************************************/ 2970 /*************************************************************************/ 2971 /**** ****/ 2972 /**** E D G E H I N T I N G ****/ 2973 /**** ****/ 2974 /*************************************************************************/ 2975 /*************************************************************************/ 2976 /*************************************************************************/ 2977 2978 2979 /* The main grid-fitting routine. */ 2980 2981 static void af_latin_hint_edges(AF_GlyphHints hints,AF_Dimension dim)2982 af_latin_hint_edges( AF_GlyphHints hints, 2983 AF_Dimension dim ) 2984 { 2985 AF_AxisHints axis = &hints->axis[dim]; 2986 AF_Edge edges = axis->edges; 2987 AF_Edge edge_limit = edges + axis->num_edges; 2988 FT_PtrDist n_edges; 2989 AF_Edge edge; 2990 AF_Edge anchor = NULL; 2991 FT_Int has_serifs = 0; 2992 2993 AF_StyleClass style_class = hints->metrics->style_class; 2994 AF_ScriptClass script_class = af_script_classes[style_class->script]; 2995 2996 FT_Bool top_to_bottom_hinting = 0; 2997 2998 #ifdef FT_DEBUG_LEVEL_TRACE 2999 FT_UInt num_actions = 0; 3000 #endif 3001 3002 3003 FT_TRACE5(( "latin %s edge hinting (style `%s')\n", 3004 dim == AF_DIMENSION_VERT ? "horizontal" : "vertical", 3005 af_style_names[hints->metrics->style_class->style] )); 3006 3007 if ( dim == AF_DIMENSION_VERT ) 3008 top_to_bottom_hinting = script_class->top_to_bottom_hinting; 3009 3010 /* we begin by aligning all stems relative to the blue zone */ 3011 /* if needed -- that's only for horizontal edges */ 3012 3013 if ( dim == AF_DIMENSION_VERT && AF_HINTS_DO_BLUES( hints ) ) 3014 { 3015 for ( edge = edges; edge < edge_limit; edge++ ) 3016 { 3017 AF_Width blue; 3018 AF_Edge edge1, edge2; /* these edges form the stem to check */ 3019 3020 3021 if ( edge->flags & AF_EDGE_DONE ) 3022 continue; 3023 3024 edge1 = NULL; 3025 edge2 = edge->link; 3026 3027 /* 3028 * If a stem contains both a neutral and a non-neutral blue zone, 3029 * skip the neutral one. Otherwise, outlines with different 3030 * directions might be incorrectly aligned at the same vertical 3031 * position. 3032 * 3033 * If we have two neutral blue zones, skip one of them. 3034 * 3035 */ 3036 if ( edge->blue_edge && edge2 && edge2->blue_edge ) 3037 { 3038 FT_Byte neutral = edge->flags & AF_EDGE_NEUTRAL; 3039 FT_Byte neutral2 = edge2->flags & AF_EDGE_NEUTRAL; 3040 3041 3042 if ( neutral2 ) 3043 { 3044 edge2->blue_edge = NULL; 3045 edge2->flags &= ~AF_EDGE_NEUTRAL; 3046 } 3047 else if ( neutral ) 3048 { 3049 edge->blue_edge = NULL; 3050 edge->flags &= ~AF_EDGE_NEUTRAL; 3051 } 3052 } 3053 3054 blue = edge->blue_edge; 3055 if ( blue ) 3056 edge1 = edge; 3057 3058 /* flip edges if the other edge is aligned to a blue zone */ 3059 else if ( edge2 && edge2->blue_edge ) 3060 { 3061 blue = edge2->blue_edge; 3062 edge1 = edge2; 3063 edge2 = edge; 3064 } 3065 3066 if ( !edge1 ) 3067 continue; 3068 3069 #ifdef FT_DEBUG_LEVEL_TRACE 3070 if ( !anchor ) 3071 FT_TRACE5(( " BLUE_ANCHOR: edge %ld (opos=%.2f) snapped to %.2f," 3072 " was %.2f (anchor=edge %ld)\n", 3073 edge1 - edges, edge1->opos / 64.0, blue->fit / 64.0, 3074 edge1->pos / 64.0, edge - edges )); 3075 else 3076 FT_TRACE5(( " BLUE: edge %ld (opos=%.2f) snapped to %.2f," 3077 " was %.2f\n", 3078 edge1 - edges, edge1->opos / 64.0, blue->fit / 64.0, 3079 edge1->pos / 64.0 )); 3080 3081 num_actions++; 3082 #endif 3083 3084 edge1->pos = blue->fit; 3085 edge1->flags |= AF_EDGE_DONE; 3086 3087 if ( edge2 && !edge2->blue_edge ) 3088 { 3089 af_latin_align_linked_edge( hints, dim, edge1, edge2 ); 3090 edge2->flags |= AF_EDGE_DONE; 3091 3092 #ifdef FT_DEBUG_LEVEL_TRACE 3093 num_actions++; 3094 #endif 3095 } 3096 3097 if ( !anchor ) 3098 anchor = edge; 3099 } 3100 } 3101 3102 /* now we align all other stem edges, trying to maintain the */ 3103 /* relative order of stems in the glyph */ 3104 for ( edge = edges; edge < edge_limit; edge++ ) 3105 { 3106 AF_Edge edge2; 3107 3108 3109 if ( edge->flags & AF_EDGE_DONE ) 3110 continue; 3111 3112 /* skip all non-stem edges */ 3113 edge2 = edge->link; 3114 if ( !edge2 ) 3115 { 3116 has_serifs++; 3117 continue; 3118 } 3119 3120 /* now align the stem */ 3121 3122 /* this should not happen, but it's better to be safe */ 3123 if ( edge2->blue_edge ) 3124 { 3125 FT_TRACE5(( " ASSERTION FAILED for edge %ld\n", edge2 - edges )); 3126 3127 af_latin_align_linked_edge( hints, dim, edge2, edge ); 3128 edge->flags |= AF_EDGE_DONE; 3129 3130 #ifdef FT_DEBUG_LEVEL_TRACE 3131 num_actions++; 3132 #endif 3133 continue; 3134 } 3135 3136 if ( !anchor ) 3137 { 3138 /* if we reach this if clause, no stem has been aligned yet */ 3139 3140 FT_Pos org_len, org_center, cur_len; 3141 FT_Pos cur_pos1, error1, error2, u_off, d_off; 3142 3143 3144 org_len = edge2->opos - edge->opos; 3145 cur_len = af_latin_compute_stem_width( hints, dim, 3146 org_len, 0, 3147 edge->flags, 3148 edge2->flags ); 3149 3150 /* some voodoo to specially round edges for small stem widths; */ 3151 /* the idea is to align the center of a stem, then shifting */ 3152 /* the stem edges to suitable positions */ 3153 if ( cur_len <= 64 ) 3154 { 3155 /* width <= 1px */ 3156 u_off = 32; 3157 d_off = 32; 3158 } 3159 else 3160 { 3161 /* 1px < width < 1.5px */ 3162 u_off = 38; 3163 d_off = 26; 3164 } 3165 3166 if ( cur_len < 96 ) 3167 { 3168 org_center = edge->opos + ( org_len >> 1 ); 3169 cur_pos1 = FT_PIX_ROUND( org_center ); 3170 3171 error1 = org_center - ( cur_pos1 - u_off ); 3172 if ( error1 < 0 ) 3173 error1 = -error1; 3174 3175 error2 = org_center - ( cur_pos1 + d_off ); 3176 if ( error2 < 0 ) 3177 error2 = -error2; 3178 3179 if ( error1 < error2 ) 3180 cur_pos1 -= u_off; 3181 else 3182 cur_pos1 += d_off; 3183 3184 edge->pos = cur_pos1 - cur_len / 2; 3185 edge2->pos = edge->pos + cur_len; 3186 } 3187 else 3188 edge->pos = FT_PIX_ROUND( edge->opos ); 3189 3190 anchor = edge; 3191 edge->flags |= AF_EDGE_DONE; 3192 3193 FT_TRACE5(( " ANCHOR: edge %ld (opos=%.2f) and %ld (opos=%.2f)" 3194 " snapped to %.2f and %.2f\n", 3195 edge - edges, edge->opos / 64.0, 3196 edge2 - edges, edge2->opos / 64.0, 3197 edge->pos / 64.0, edge2->pos / 64.0 )); 3198 3199 af_latin_align_linked_edge( hints, dim, edge, edge2 ); 3200 3201 #ifdef FT_DEBUG_LEVEL_TRACE 3202 num_actions += 2; 3203 #endif 3204 } 3205 else 3206 { 3207 FT_Pos org_pos, org_len, org_center, cur_len; 3208 FT_Pos cur_pos1, cur_pos2, delta1, delta2; 3209 3210 3211 org_pos = anchor->pos + ( edge->opos - anchor->opos ); 3212 org_len = edge2->opos - edge->opos; 3213 org_center = org_pos + ( org_len >> 1 ); 3214 3215 cur_len = af_latin_compute_stem_width( hints, dim, 3216 org_len, 0, 3217 edge->flags, 3218 edge2->flags ); 3219 3220 if ( edge2->flags & AF_EDGE_DONE ) 3221 { 3222 FT_TRACE5(( " ADJUST: edge %ld (pos=%.2f) moved to %.2f\n", 3223 edge - edges, edge->pos / 64.0, 3224 ( edge2->pos - cur_len ) / 64.0 )); 3225 3226 edge->pos = edge2->pos - cur_len; 3227 } 3228 3229 else if ( cur_len < 96 ) 3230 { 3231 FT_Pos u_off, d_off; 3232 3233 3234 cur_pos1 = FT_PIX_ROUND( org_center ); 3235 3236 if ( cur_len <= 64 ) 3237 { 3238 u_off = 32; 3239 d_off = 32; 3240 } 3241 else 3242 { 3243 u_off = 38; 3244 d_off = 26; 3245 } 3246 3247 delta1 = org_center - ( cur_pos1 - u_off ); 3248 if ( delta1 < 0 ) 3249 delta1 = -delta1; 3250 3251 delta2 = org_center - ( cur_pos1 + d_off ); 3252 if ( delta2 < 0 ) 3253 delta2 = -delta2; 3254 3255 if ( delta1 < delta2 ) 3256 cur_pos1 -= u_off; 3257 else 3258 cur_pos1 += d_off; 3259 3260 edge->pos = cur_pos1 - cur_len / 2; 3261 edge2->pos = cur_pos1 + cur_len / 2; 3262 3263 FT_TRACE5(( " STEM: edge %ld (opos=%.2f) linked to %ld (opos=%.2f)" 3264 " snapped to %.2f and %.2f\n", 3265 edge - edges, edge->opos / 64.0, 3266 edge2 - edges, edge2->opos / 64.0, 3267 edge->pos / 64.0, edge2->pos / 64.0 )); 3268 } 3269 3270 else 3271 { 3272 org_pos = anchor->pos + ( edge->opos - anchor->opos ); 3273 org_len = edge2->opos - edge->opos; 3274 org_center = org_pos + ( org_len >> 1 ); 3275 3276 cur_len = af_latin_compute_stem_width( hints, dim, 3277 org_len, 0, 3278 edge->flags, 3279 edge2->flags ); 3280 3281 cur_pos1 = FT_PIX_ROUND( org_pos ); 3282 delta1 = cur_pos1 + ( cur_len >> 1 ) - org_center; 3283 if ( delta1 < 0 ) 3284 delta1 = -delta1; 3285 3286 cur_pos2 = FT_PIX_ROUND( org_pos + org_len ) - cur_len; 3287 delta2 = cur_pos2 + ( cur_len >> 1 ) - org_center; 3288 if ( delta2 < 0 ) 3289 delta2 = -delta2; 3290 3291 edge->pos = ( delta1 < delta2 ) ? cur_pos1 : cur_pos2; 3292 edge2->pos = edge->pos + cur_len; 3293 3294 FT_TRACE5(( " STEM: edge %ld (opos=%.2f) linked to %ld (opos=%.2f)" 3295 " snapped to %.2f and %.2f\n", 3296 edge - edges, edge->opos / 64.0, 3297 edge2 - edges, edge2->opos / 64.0, 3298 edge->pos / 64.0, edge2->pos / 64.0 )); 3299 } 3300 3301 #ifdef FT_DEBUG_LEVEL_TRACE 3302 num_actions++; 3303 #endif 3304 3305 edge->flags |= AF_EDGE_DONE; 3306 edge2->flags |= AF_EDGE_DONE; 3307 3308 if ( edge > edges && 3309 ( top_to_bottom_hinting ? ( edge->pos > edge[-1].pos ) 3310 : ( edge->pos < edge[-1].pos ) ) ) 3311 { 3312 /* don't move if stem would (almost) disappear otherwise; */ 3313 /* the ad-hoc value 16 corresponds to 1/4px */ 3314 if ( edge->link && FT_ABS( edge->link->pos - edge[-1].pos ) > 16 ) 3315 { 3316 #ifdef FT_DEBUG_LEVEL_TRACE 3317 FT_TRACE5(( " BOUND: edge %ld (pos=%.2f) moved to %.2f\n", 3318 edge - edges, 3319 edge->pos / 64.0, 3320 edge[-1].pos / 64.0 )); 3321 3322 num_actions++; 3323 #endif 3324 3325 edge->pos = edge[-1].pos; 3326 } 3327 } 3328 } 3329 } 3330 3331 /* make sure that lowercase m's maintain their symmetry */ 3332 3333 /* In general, lowercase m's have six vertical edges if they are sans */ 3334 /* serif, or twelve if they are with serifs. This implementation is */ 3335 /* based on that assumption, and seems to work very well with most */ 3336 /* faces. However, if for a certain face this assumption is not */ 3337 /* true, the m is just rendered like before. In addition, any stem */ 3338 /* correction will only be applied to symmetrical glyphs (even if the */ 3339 /* glyph is not an m), so the potential for unwanted distortion is */ 3340 /* relatively low. */ 3341 3342 /* We don't handle horizontal edges since we can't easily assure that */ 3343 /* the third (lowest) stem aligns with the base line; it might end up */ 3344 /* one pixel higher or lower. */ 3345 3346 n_edges = edge_limit - edges; 3347 if ( dim == AF_DIMENSION_HORZ && ( n_edges == 6 || n_edges == 12 ) ) 3348 { 3349 AF_Edge edge1, edge2, edge3; 3350 FT_Pos dist1, dist2, span, delta; 3351 3352 3353 if ( n_edges == 6 ) 3354 { 3355 edge1 = edges; 3356 edge2 = edges + 2; 3357 edge3 = edges + 4; 3358 } 3359 else 3360 { 3361 edge1 = edges + 1; 3362 edge2 = edges + 5; 3363 edge3 = edges + 9; 3364 } 3365 3366 dist1 = edge2->opos - edge1->opos; 3367 dist2 = edge3->opos - edge2->opos; 3368 3369 span = dist1 - dist2; 3370 if ( span < 0 ) 3371 span = -span; 3372 3373 if ( span < 8 ) 3374 { 3375 delta = edge3->pos - ( 2 * edge2->pos - edge1->pos ); 3376 edge3->pos -= delta; 3377 if ( edge3->link ) 3378 edge3->link->pos -= delta; 3379 3380 /* move the serifs along with the stem */ 3381 if ( n_edges == 12 ) 3382 { 3383 ( edges + 8 )->pos -= delta; 3384 ( edges + 11 )->pos -= delta; 3385 } 3386 3387 edge3->flags |= AF_EDGE_DONE; 3388 if ( edge3->link ) 3389 edge3->link->flags |= AF_EDGE_DONE; 3390 } 3391 } 3392 3393 if ( has_serifs || !anchor ) 3394 { 3395 /* 3396 * now hint the remaining edges (serifs and single) in order 3397 * to complete our processing 3398 */ 3399 for ( edge = edges; edge < edge_limit; edge++ ) 3400 { 3401 FT_Pos delta; 3402 3403 3404 if ( edge->flags & AF_EDGE_DONE ) 3405 continue; 3406 3407 delta = 1000; 3408 3409 if ( edge->serif ) 3410 { 3411 delta = edge->serif->opos - edge->opos; 3412 if ( delta < 0 ) 3413 delta = -delta; 3414 } 3415 3416 if ( delta < 64 + 16 ) 3417 { 3418 af_latin_align_serif_edge( hints, edge->serif, edge ); 3419 FT_TRACE5(( " SERIF: edge %ld (opos=%.2f) serif to %ld (opos=%.2f)" 3420 " aligned to %.2f\n", 3421 edge - edges, edge->opos / 64.0, 3422 edge->serif - edges, edge->serif->opos / 64.0, 3423 edge->pos / 64.0 )); 3424 } 3425 else if ( !anchor ) 3426 { 3427 edge->pos = FT_PIX_ROUND( edge->opos ); 3428 anchor = edge; 3429 FT_TRACE5(( " SERIF_ANCHOR: edge %ld (opos=%.2f)" 3430 " snapped to %.2f\n", 3431 edge-edges, edge->opos / 64.0, edge->pos / 64.0 )); 3432 } 3433 else 3434 { 3435 AF_Edge before, after; 3436 3437 3438 for ( before = edge - 1; before >= edges; before-- ) 3439 if ( before->flags & AF_EDGE_DONE ) 3440 break; 3441 3442 for ( after = edge + 1; after < edge_limit; after++ ) 3443 if ( after->flags & AF_EDGE_DONE ) 3444 break; 3445 3446 if ( before >= edges && before < edge && 3447 after < edge_limit && after > edge ) 3448 { 3449 if ( after->opos == before->opos ) 3450 edge->pos = before->pos; 3451 else 3452 edge->pos = before->pos + 3453 FT_MulDiv( edge->opos - before->opos, 3454 after->pos - before->pos, 3455 after->opos - before->opos ); 3456 3457 FT_TRACE5(( " SERIF_LINK1: edge %ld (opos=%.2f) snapped to %.2f" 3458 " from %ld (opos=%.2f)\n", 3459 edge - edges, edge->opos / 64.0, 3460 edge->pos / 64.0, 3461 before - edges, before->opos / 64.0 )); 3462 } 3463 else 3464 { 3465 edge->pos = anchor->pos + 3466 ( ( edge->opos - anchor->opos + 16 ) & ~31 ); 3467 FT_TRACE5(( " SERIF_LINK2: edge %ld (opos=%.2f)" 3468 " snapped to %.2f\n", 3469 edge - edges, edge->opos / 64.0, edge->pos / 64.0 )); 3470 } 3471 } 3472 3473 #ifdef FT_DEBUG_LEVEL_TRACE 3474 num_actions++; 3475 #endif 3476 edge->flags |= AF_EDGE_DONE; 3477 3478 if ( edge > edges && 3479 ( top_to_bottom_hinting ? ( edge->pos > edge[-1].pos ) 3480 : ( edge->pos < edge[-1].pos ) ) ) 3481 { 3482 /* don't move if stem would (almost) disappear otherwise; */ 3483 /* the ad-hoc value 16 corresponds to 1/4px */ 3484 if ( edge->link && FT_ABS( edge->link->pos - edge[-1].pos ) > 16 ) 3485 { 3486 #ifdef FT_DEBUG_LEVEL_TRACE 3487 FT_TRACE5(( " BOUND: edge %ld (pos=%.2f) moved to %.2f\n", 3488 edge - edges, 3489 edge->pos / 64.0, 3490 edge[-1].pos / 64.0 )); 3491 3492 num_actions++; 3493 #endif 3494 edge->pos = edge[-1].pos; 3495 } 3496 } 3497 3498 if ( edge + 1 < edge_limit && 3499 edge[1].flags & AF_EDGE_DONE && 3500 ( top_to_bottom_hinting ? ( edge->pos < edge[1].pos ) 3501 : ( edge->pos > edge[1].pos ) ) ) 3502 { 3503 /* don't move if stem would (almost) disappear otherwise; */ 3504 /* the ad-hoc value 16 corresponds to 1/4px */ 3505 if ( edge->link && FT_ABS( edge->link->pos - edge[-1].pos ) > 16 ) 3506 { 3507 #ifdef FT_DEBUG_LEVEL_TRACE 3508 FT_TRACE5(( " BOUND: edge %ld (pos=%.2f) moved to %.2f\n", 3509 edge - edges, 3510 edge->pos / 64.0, 3511 edge[1].pos / 64.0 )); 3512 3513 num_actions++; 3514 #endif 3515 3516 edge->pos = edge[1].pos; 3517 } 3518 } 3519 } 3520 } 3521 3522 #ifdef FT_DEBUG_LEVEL_TRACE 3523 if ( !num_actions ) 3524 FT_TRACE5(( " (none)\n" )); 3525 FT_TRACE5(( "\n" )); 3526 #endif 3527 } 3528 3529 3530 /* Apply the complete hinting algorithm to a latin glyph. */ 3531 3532 static FT_Error af_latin_hints_apply(FT_UInt glyph_index,AF_GlyphHints hints,FT_Outline * outline,AF_LatinMetrics metrics)3533 af_latin_hints_apply( FT_UInt glyph_index, 3534 AF_GlyphHints hints, 3535 FT_Outline* outline, 3536 AF_LatinMetrics metrics ) 3537 { 3538 FT_Error error; 3539 int dim; 3540 3541 AF_LatinAxis axis; 3542 3543 3544 error = af_glyph_hints_reload( hints, outline ); 3545 if ( error ) 3546 goto Exit; 3547 3548 /* analyze glyph outline */ 3549 if ( AF_HINTS_DO_HORIZONTAL( hints ) ) 3550 { 3551 axis = &metrics->axis[AF_DIMENSION_HORZ]; 3552 error = af_latin_hints_detect_features( hints, 3553 axis->width_count, 3554 axis->widths, 3555 AF_DIMENSION_HORZ ); 3556 if ( error ) 3557 goto Exit; 3558 } 3559 3560 if ( AF_HINTS_DO_VERTICAL( hints ) ) 3561 { 3562 axis = &metrics->axis[AF_DIMENSION_VERT]; 3563 error = af_latin_hints_detect_features( hints, 3564 axis->width_count, 3565 axis->widths, 3566 AF_DIMENSION_VERT ); 3567 if ( error ) 3568 goto Exit; 3569 3570 /* apply blue zones to base characters only */ 3571 if ( !( metrics->root.globals->glyph_styles[glyph_index] & AF_NONBASE ) ) 3572 af_latin_hints_compute_blue_edges( hints, metrics ); 3573 } 3574 3575 /* grid-fit the outline */ 3576 for ( dim = 0; dim < AF_DIMENSION_MAX; dim++ ) 3577 { 3578 #ifdef AF_CONFIG_OPTION_USE_WARPER 3579 if ( dim == AF_DIMENSION_HORZ && 3580 metrics->root.scaler.render_mode == FT_RENDER_MODE_NORMAL && 3581 AF_HINTS_DO_WARP( hints ) ) 3582 { 3583 AF_WarperRec warper; 3584 FT_Fixed scale; 3585 FT_Pos delta; 3586 3587 3588 af_warper_compute( &warper, hints, (AF_Dimension)dim, 3589 &scale, &delta ); 3590 af_glyph_hints_scale_dim( hints, (AF_Dimension)dim, 3591 scale, delta ); 3592 continue; 3593 } 3594 #endif /* AF_CONFIG_OPTION_USE_WARPER */ 3595 3596 if ( ( dim == AF_DIMENSION_HORZ && AF_HINTS_DO_HORIZONTAL( hints ) ) || 3597 ( dim == AF_DIMENSION_VERT && AF_HINTS_DO_VERTICAL( hints ) ) ) 3598 { 3599 af_latin_hint_edges( hints, (AF_Dimension)dim ); 3600 af_glyph_hints_align_edge_points( hints, (AF_Dimension)dim ); 3601 af_glyph_hints_align_strong_points( hints, (AF_Dimension)dim ); 3602 af_glyph_hints_align_weak_points( hints, (AF_Dimension)dim ); 3603 } 3604 } 3605 3606 af_glyph_hints_save( hints, outline ); 3607 3608 Exit: 3609 return error; 3610 } 3611 3612 3613 /*************************************************************************/ 3614 /*************************************************************************/ 3615 /***** *****/ 3616 /***** L A T I N S C R I P T C L A S S *****/ 3617 /***** *****/ 3618 /*************************************************************************/ 3619 /*************************************************************************/ 3620 3621 3622 AF_DEFINE_WRITING_SYSTEM_CLASS( 3623 af_latin_writing_system_class, 3624 3625 AF_WRITING_SYSTEM_LATIN, 3626 3627 sizeof ( AF_LatinMetricsRec ), 3628 3629 (AF_WritingSystem_InitMetricsFunc) af_latin_metrics_init, /* style_metrics_init */ 3630 (AF_WritingSystem_ScaleMetricsFunc)af_latin_metrics_scale, /* style_metrics_scale */ 3631 (AF_WritingSystem_DoneMetricsFunc) NULL, /* style_metrics_done */ 3632 (AF_WritingSystem_GetStdWidthsFunc)af_latin_get_standard_widths, /* style_metrics_getstdw */ 3633 3634 (AF_WritingSystem_InitHintsFunc) af_latin_hints_init, /* style_hints_init */ 3635 (AF_WritingSystem_ApplyHintsFunc) af_latin_hints_apply /* style_hints_apply */ 3636 ) 3637 3638 3639 /* END */ 3640