1 /* ATTENTION: This file doesn't compile. It is only here as a reference */ 2 /* of an alternative latin hinting algorithm that was always */ 3 /* marked as experimental. */ 4 5 6 /***************************************************************************/ 7 /* */ 8 /* aflatin2.c */ 9 /* */ 10 /* Auto-fitter hinting routines for latin writing system (body). */ 11 /* */ 12 /* Copyright 2003-2018 by */ 13 /* David Turner, Robert Wilhelm, and Werner Lemberg. */ 14 /* */ 15 /* This file is part of the FreeType project, and may only be used, */ 16 /* modified, and distributed under the terms of the FreeType project */ 17 /* license, LICENSE.TXT. By continuing to use, modify, or distribute */ 18 /* this file you indicate that you have read the license and */ 19 /* understand and accept it fully. */ 20 /* */ 21 /***************************************************************************/ 22 23 24 #include FT_ADVANCES_H 25 26 27 #ifdef FT_OPTION_AUTOFIT2 28 29 #include "afglobal.h" 30 #include "aflatin.h" 31 #include "aflatin2.h" 32 #include "aferrors.h" 33 34 35 #ifdef AF_CONFIG_OPTION_USE_WARPER 36 #include "afwarp.h" 37 #endif 38 39 40 /*************************************************************************/ 41 /* */ 42 /* The macro FT_COMPONENT is used in trace mode. It is an implicit */ 43 /* parameter of the FT_TRACE() and FT_ERROR() macros, used to print/log */ 44 /* messages during execution. */ 45 /* */ 46 #undef FT_COMPONENT 47 #define FT_COMPONENT trace_aflatin2 48 49 50 FT_LOCAL_DEF( FT_Error ) 51 af_latin2_hints_compute_segments( AF_GlyphHints hints, 52 AF_Dimension dim ); 53 54 FT_LOCAL_DEF( void ) 55 af_latin2_hints_link_segments( AF_GlyphHints hints, 56 AF_Dimension dim ); 57 58 /*************************************************************************/ 59 /*************************************************************************/ 60 /***** *****/ 61 /***** L A T I N G L O B A L M E T R I C S *****/ 62 /***** *****/ 63 /*************************************************************************/ 64 /*************************************************************************/ 65 66 FT_LOCAL_DEF( void ) 67 af_latin2_metrics_init_widths( AF_LatinMetrics metrics, 68 FT_Face face ) 69 { 70 /* scan the array of segments in each direction */ 71 AF_GlyphHintsRec hints[1]; 72 73 74 af_glyph_hints_init( hints, face->memory ); 75 76 metrics->axis[AF_DIMENSION_HORZ].width_count = 0; 77 metrics->axis[AF_DIMENSION_VERT].width_count = 0; 78 79 { 80 FT_Error error; 81 FT_UInt glyph_index; 82 int dim; 83 AF_LatinMetricsRec dummy[1]; 84 AF_Scaler scaler = &dummy->root.scaler; 85 86 87 glyph_index = FT_Get_Char_Index( 88 face, 89 metrics->root.style_class->standard_char ); 90 if ( glyph_index == 0 ) 91 goto Exit; 92 93 error = FT_Load_Glyph( face, glyph_index, FT_LOAD_NO_SCALE ); 94 if ( error || face->glyph->outline.n_points <= 0 ) 95 goto Exit; 96 97 FT_ZERO( dummy ); 98 99 dummy->units_per_em = metrics->units_per_em; 100 scaler->x_scale = scaler->y_scale = 0x10000L; 101 scaler->x_delta = scaler->y_delta = 0; 102 scaler->face = face; 103 scaler->render_mode = FT_RENDER_MODE_NORMAL; 104 scaler->flags = 0; 105 106 af_glyph_hints_rescale( hints, (AF_StyleMetrics)dummy ); 107 108 error = af_glyph_hints_reload( hints, &face->glyph->outline ); 109 if ( error ) 110 goto Exit; 111 112 for ( dim = 0; dim < AF_DIMENSION_MAX; dim++ ) 113 { 114 AF_LatinAxis axis = &metrics->axis[dim]; 115 AF_AxisHints axhints = &hints->axis[dim]; 116 AF_Segment seg, limit, link; 117 FT_UInt num_widths = 0; 118 119 120 error = af_latin2_hints_compute_segments( hints, 121 (AF_Dimension)dim ); 122 if ( error ) 123 goto Exit; 124 125 af_latin2_hints_link_segments( hints, 126 (AF_Dimension)dim ); 127 128 seg = axhints->segments; 129 limit = seg + axhints->num_segments; 130 131 for ( ; seg < limit; seg++ ) 132 { 133 link = seg->link; 134 135 /* we only consider stem segments there! */ 136 if ( link && link->link == seg && link > seg ) 137 { 138 FT_Pos dist; 139 140 141 dist = seg->pos - link->pos; 142 if ( dist < 0 ) 143 dist = -dist; 144 145 if ( num_widths < AF_LATIN_MAX_WIDTHS ) 146 axis->widths[num_widths++].org = dist; 147 } 148 } 149 150 af_sort_widths( num_widths, axis->widths ); 151 axis->width_count = num_widths; 152 } 153 154 Exit: 155 for ( dim = 0; dim < AF_DIMENSION_MAX; dim++ ) 156 { 157 AF_LatinAxis axis = &metrics->axis[dim]; 158 FT_Pos stdw; 159 160 161 stdw = ( axis->width_count > 0 ) 162 ? axis->widths[0].org 163 : AF_LATIN_CONSTANT( metrics, 50 ); 164 165 /* let's try 20% of the smallest width */ 166 axis->edge_distance_threshold = stdw / 5; 167 axis->standard_width = stdw; 168 axis->extra_light = 0; 169 } 170 } 171 172 af_glyph_hints_done( hints ); 173 } 174 175 176 177 #define AF_LATIN_MAX_TEST_CHARACTERS 12 178 179 180 static const char af_latin2_blue_chars[AF_LATIN_MAX_BLUES] 181 [AF_LATIN_MAX_TEST_CHARACTERS+1] = 182 { 183 "THEZOCQS", 184 "HEZLOCUS", 185 "fijkdbh", 186 "xzroesc", 187 "xzroesc", 188 "pqgjy" 189 }; 190 191 192 static void 193 af_latin2_metrics_init_blues( AF_LatinMetrics metrics, 194 FT_Face face ) 195 { 196 FT_Pos flats [AF_LATIN_MAX_TEST_CHARACTERS]; 197 FT_Pos rounds[AF_LATIN_MAX_TEST_CHARACTERS]; 198 FT_Int num_flats; 199 FT_Int num_rounds; 200 FT_Int bb; 201 AF_LatinBlue blue; 202 FT_Error error; 203 AF_LatinAxis axis = &metrics->axis[AF_DIMENSION_VERT]; 204 FT_GlyphSlot glyph = face->glyph; 205 206 207 /* we compute the blues simply by loading each character from the */ 208 /* 'af_latin2_blue_chars[blues]' string, then compute its top-most or */ 209 /* bottom-most points (depending on `AF_IS_TOP_BLUE') */ 210 211 FT_TRACE5(( "blue zones computation\n" 212 "======================\n\n" )); 213 214 for ( bb = 0; bb < AF_LATIN_BLUE_MAX; bb++ ) 215 { 216 const char* p = af_latin2_blue_chars[bb]; 217 const char* limit = p + AF_LATIN_MAX_TEST_CHARACTERS; 218 FT_Pos* blue_ref; 219 FT_Pos* blue_shoot; 220 221 222 FT_TRACE5(( "blue zone %d:\n", bb )); 223 224 num_flats = 0; 225 num_rounds = 0; 226 227 for ( ; p < limit && *p; p++ ) 228 { 229 FT_UInt glyph_index; 230 FT_Int best_point, best_y, best_first, best_last; 231 FT_Vector* points; 232 FT_Bool round; 233 234 235 /* load the character in the face -- skip unknown or empty ones */ 236 glyph_index = FT_Get_Char_Index( face, (FT_UInt)*p ); 237 if ( glyph_index == 0 ) 238 continue; 239 240 error = FT_Load_Glyph( face, glyph_index, FT_LOAD_NO_SCALE ); 241 if ( error || glyph->outline.n_points <= 0 ) 242 continue; 243 244 /* now compute min or max point indices and coordinates */ 245 points = glyph->outline.points; 246 best_point = -1; 247 best_y = 0; /* make compiler happy */ 248 best_first = 0; /* ditto */ 249 best_last = 0; /* ditto */ 250 251 { 252 FT_Int nn; 253 FT_Int first = 0; 254 FT_Int last = -1; 255 256 257 for ( nn = 0; nn < glyph->outline.n_contours; first = last+1, nn++ ) 258 { 259 FT_Int old_best_point = best_point; 260 FT_Int pp; 261 262 263 last = glyph->outline.contours[nn]; 264 265 /* Avoid single-point contours since they are never rasterized. */ 266 /* In some fonts, they correspond to mark attachment points */ 267 /* which are way outside of the glyph's real outline. */ 268 if ( last == first ) 269 continue; 270 271 if ( AF_LATIN_IS_TOP_BLUE( bb ) ) 272 { 273 for ( pp = first; pp <= last; pp++ ) 274 if ( best_point < 0 || points[pp].y > best_y ) 275 { 276 best_point = pp; 277 best_y = points[pp].y; 278 } 279 } 280 else 281 { 282 for ( pp = first; pp <= last; pp++ ) 283 if ( best_point < 0 || points[pp].y < best_y ) 284 { 285 best_point = pp; 286 best_y = points[pp].y; 287 } 288 } 289 290 if ( best_point != old_best_point ) 291 { 292 best_first = first; 293 best_last = last; 294 } 295 } 296 FT_TRACE5(( " %c %d", *p, best_y )); 297 } 298 299 /* now check whether the point belongs to a straight or round */ 300 /* segment; we first need to find in which contour the extremum */ 301 /* lies, then inspect its previous and next points */ 302 { 303 FT_Pos best_x = points[best_point].x; 304 FT_Int start, end, prev, next; 305 FT_Pos dist; 306 307 308 /* now look for the previous and next points that are not on the */ 309 /* same Y coordinate. Threshold the `closeness'... */ 310 start = end = best_point; 311 312 do 313 { 314 prev = start - 1; 315 if ( prev < best_first ) 316 prev = best_last; 317 318 dist = FT_ABS( points[prev].y - best_y ); 319 /* accept a small distance or a small angle (both values are */ 320 /* heuristic; value 20 corresponds to approx. 2.9 degrees) */ 321 if ( dist > 5 ) 322 if ( FT_ABS( points[prev].x - best_x ) <= 20 * dist ) 323 break; 324 325 start = prev; 326 327 } while ( start != best_point ); 328 329 do 330 { 331 next = end + 1; 332 if ( next > best_last ) 333 next = best_first; 334 335 dist = FT_ABS( points[next].y - best_y ); 336 if ( dist > 5 ) 337 if ( FT_ABS( points[next].x - best_x ) <= 20 * dist ) 338 break; 339 340 end = next; 341 342 } while ( end != best_point ); 343 344 /* now, set the `round' flag depending on the segment's kind */ 345 round = FT_BOOL( 346 FT_CURVE_TAG( glyph->outline.tags[start] ) != FT_CURVE_TAG_ON || 347 FT_CURVE_TAG( glyph->outline.tags[ end ] ) != FT_CURVE_TAG_ON ); 348 349 FT_TRACE5(( " (%s)\n", round ? "round" : "flat" )); 350 } 351 352 if ( round ) 353 rounds[num_rounds++] = best_y; 354 else 355 flats[num_flats++] = best_y; 356 } 357 358 if ( num_flats == 0 && num_rounds == 0 ) 359 { 360 /* 361 * we couldn't find a single glyph to compute this blue zone, 362 * we will simply ignore it then 363 */ 364 FT_TRACE5(( " empty\n" )); 365 continue; 366 } 367 368 /* we have computed the contents of the `rounds' and `flats' tables, */ 369 /* now determine the reference and overshoot position of the blue -- */ 370 /* we simply take the median value after a simple sort */ 371 af_sort_pos( num_rounds, rounds ); 372 af_sort_pos( num_flats, flats ); 373 374 blue = & axis->blues[axis->blue_count]; 375 blue_ref = & blue->ref.org; 376 blue_shoot = & blue->shoot.org; 377 378 axis->blue_count++; 379 380 if ( num_flats == 0 ) 381 { 382 *blue_ref = 383 *blue_shoot = rounds[num_rounds / 2]; 384 } 385 else if ( num_rounds == 0 ) 386 { 387 *blue_ref = 388 *blue_shoot = flats[num_flats / 2]; 389 } 390 else 391 { 392 *blue_ref = flats[num_flats / 2]; 393 *blue_shoot = rounds[num_rounds / 2]; 394 } 395 396 /* there are sometimes problems: if the overshoot position of top */ 397 /* zones is under its reference position, or the opposite for bottom */ 398 /* zones. We must thus check everything there and correct the errors */ 399 if ( *blue_shoot != *blue_ref ) 400 { 401 FT_Pos ref = *blue_ref; 402 FT_Pos shoot = *blue_shoot; 403 FT_Bool over_ref = FT_BOOL( shoot > ref ); 404 405 406 if ( AF_LATIN_IS_TOP_BLUE( bb ) ^ over_ref ) 407 { 408 *blue_ref = 409 *blue_shoot = ( shoot + ref ) / 2; 410 411 FT_TRACE5(( " [overshoot smaller than reference," 412 " taking mean value]\n" )); 413 } 414 } 415 416 blue->flags = 0; 417 if ( AF_LATIN_IS_TOP_BLUE( bb ) ) 418 blue->flags |= AF_LATIN_BLUE_TOP; 419 420 /* 421 * The following flag is used later to adjust the y and x scales 422 * in order to optimize the pixel grid alignment of the top of small 423 * letters. 424 */ 425 if ( AF_LATIN_IS_X_HEIGHT_BLUE( bb ) ) 426 blue->flags |= AF_LATIN_BLUE_ADJUSTMENT; 427 428 FT_TRACE5(( " -> reference = %ld\n" 429 " overshoot = %ld\n", 430 *blue_ref, *blue_shoot )); 431 } 432 433 return; 434 } 435 436 437 FT_LOCAL_DEF( void ) 438 af_latin2_metrics_check_digits( AF_LatinMetrics metrics, 439 FT_Face face ) 440 { 441 FT_UInt i; 442 FT_Bool started = 0, same_width = 1; 443 FT_Fixed advance, old_advance = 0; 444 445 446 /* check whether all ASCII digits have the same advance width; */ 447 /* digit `0' is 0x30 in all supported charmaps */ 448 for ( i = 0x30; i <= 0x39; i++ ) 449 { 450 FT_UInt glyph_index; 451 452 453 glyph_index = FT_Get_Char_Index( face, i ); 454 if ( glyph_index == 0 ) 455 continue; 456 457 if ( FT_Get_Advance( face, glyph_index, 458 FT_LOAD_NO_SCALE | 459 FT_LOAD_NO_HINTING | 460 FT_LOAD_IGNORE_TRANSFORM, 461 &advance ) ) 462 continue; 463 464 if ( started ) 465 { 466 if ( advance != old_advance ) 467 { 468 same_width = 0; 469 break; 470 } 471 } 472 else 473 { 474 old_advance = advance; 475 started = 1; 476 } 477 } 478 479 metrics->root.digits_have_same_width = same_width; 480 } 481 482 483 FT_LOCAL_DEF( FT_Error ) 484 af_latin2_metrics_init( AF_LatinMetrics metrics, 485 FT_Face face ) 486 { 487 FT_Error error = FT_Err_Ok; 488 FT_CharMap oldmap = face->charmap; 489 FT_UInt ee; 490 491 static const FT_Encoding latin_encodings[] = 492 { 493 FT_ENCODING_UNICODE, 494 FT_ENCODING_APPLE_ROMAN, 495 FT_ENCODING_ADOBE_STANDARD, 496 FT_ENCODING_ADOBE_LATIN_1, 497 FT_ENCODING_NONE /* end of list */ 498 }; 499 500 501 metrics->units_per_em = face->units_per_EM; 502 503 /* do we have a latin charmap in there? */ 504 for ( ee = 0; latin_encodings[ee] != FT_ENCODING_NONE; ee++ ) 505 { 506 error = FT_Select_Charmap( face, latin_encodings[ee] ); 507 if ( !error ) 508 break; 509 } 510 511 if ( !error ) 512 { 513 af_latin2_metrics_init_widths( metrics, face ); 514 af_latin2_metrics_init_blues( metrics, face ); 515 af_latin2_metrics_check_digits( metrics, face ); 516 } 517 518 FT_Set_Charmap( face, oldmap ); 519 return FT_Err_Ok; 520 } 521 522 523 static void 524 af_latin2_metrics_scale_dim( AF_LatinMetrics metrics, 525 AF_Scaler scaler, 526 AF_Dimension dim ) 527 { 528 FT_Fixed scale; 529 FT_Pos delta; 530 AF_LatinAxis axis; 531 FT_UInt nn; 532 533 534 if ( dim == AF_DIMENSION_HORZ ) 535 { 536 scale = scaler->x_scale; 537 delta = scaler->x_delta; 538 } 539 else 540 { 541 scale = scaler->y_scale; 542 delta = scaler->y_delta; 543 } 544 545 axis = &metrics->axis[dim]; 546 547 if ( axis->org_scale == scale && axis->org_delta == delta ) 548 return; 549 550 axis->org_scale = scale; 551 axis->org_delta = delta; 552 553 /* 554 * correct Y scale to optimize the alignment of the top of small 555 * letters to the pixel grid 556 */ 557 if ( dim == AF_DIMENSION_VERT ) 558 { 559 AF_LatinAxis vaxis = &metrics->axis[AF_DIMENSION_VERT]; 560 AF_LatinBlue blue = NULL; 561 562 563 for ( nn = 0; nn < vaxis->blue_count; nn++ ) 564 { 565 if ( vaxis->blues[nn].flags & AF_LATIN_BLUE_ADJUSTMENT ) 566 { 567 blue = &vaxis->blues[nn]; 568 break; 569 } 570 } 571 572 if ( blue ) 573 { 574 FT_Pos scaled; 575 FT_Pos threshold; 576 FT_Pos fitted; 577 FT_UInt limit; 578 FT_UInt ppem; 579 580 581 scaled = FT_MulFix( blue->shoot.org, scaler->y_scale ); 582 ppem = metrics->root.scaler.face->size->metrics.x_ppem; 583 limit = metrics->root.globals->increase_x_height; 584 threshold = 40; 585 586 /* if the `increase-x-height' property is active, */ 587 /* we round up much more often */ 588 if ( limit && 589 ppem <= limit && 590 ppem >= AF_PROP_INCREASE_X_HEIGHT_MIN ) 591 threshold = 52; 592 593 fitted = ( scaled + threshold ) & ~63; 594 595 #if 1 596 if ( scaled != fitted ) 597 { 598 scale = FT_MulDiv( scale, fitted, scaled ); 599 FT_TRACE5(( "== scaled x-top = %.2g" 600 " fitted = %.2g, scaling = %.4g\n", 601 scaled / 64.0, fitted / 64.0, 602 ( fitted * 1.0 ) / scaled )); 603 } 604 #endif 605 } 606 } 607 608 axis->scale = scale; 609 axis->delta = delta; 610 611 if ( dim == AF_DIMENSION_HORZ ) 612 { 613 metrics->root.scaler.x_scale = scale; 614 metrics->root.scaler.x_delta = delta; 615 } 616 else 617 { 618 metrics->root.scaler.y_scale = scale; 619 metrics->root.scaler.y_delta = delta; 620 } 621 622 /* scale the standard widths */ 623 for ( nn = 0; nn < axis->width_count; nn++ ) 624 { 625 AF_Width width = axis->widths + nn; 626 627 628 width->cur = FT_MulFix( width->org, scale ); 629 width->fit = width->cur; 630 } 631 632 /* an extra-light axis corresponds to a standard width that is */ 633 /* smaller than 5/8 pixels */ 634 axis->extra_light = 635 (FT_Bool)( FT_MulFix( axis->standard_width, scale ) < 32 + 8 ); 636 637 if ( dim == AF_DIMENSION_VERT ) 638 { 639 /* scale the blue zones */ 640 for ( nn = 0; nn < axis->blue_count; nn++ ) 641 { 642 AF_LatinBlue blue = &axis->blues[nn]; 643 FT_Pos dist; 644 645 646 blue->ref.cur = FT_MulFix( blue->ref.org, scale ) + delta; 647 blue->ref.fit = blue->ref.cur; 648 blue->shoot.cur = FT_MulFix( blue->shoot.org, scale ) + delta; 649 blue->shoot.fit = blue->shoot.cur; 650 blue->flags &= ~AF_LATIN_BLUE_ACTIVE; 651 652 /* a blue zone is only active if it is less than 3/4 pixels tall */ 653 dist = FT_MulFix( blue->ref.org - blue->shoot.org, scale ); 654 if ( dist <= 48 && dist >= -48 ) 655 { 656 FT_Pos delta1, delta2; 657 658 delta1 = blue->shoot.org - blue->ref.org; 659 delta2 = delta1; 660 if ( delta1 < 0 ) 661 delta2 = -delta2; 662 663 delta2 = FT_MulFix( delta2, scale ); 664 665 if ( delta2 < 32 ) 666 delta2 = 0; 667 else if ( delta2 < 64 ) 668 delta2 = 32 + ( ( ( delta2 - 32 ) + 16 ) & ~31 ); 669 else 670 delta2 = FT_PIX_ROUND( delta2 ); 671 672 if ( delta1 < 0 ) 673 delta2 = -delta2; 674 675 blue->ref.fit = FT_PIX_ROUND( blue->ref.cur ); 676 blue->shoot.fit = blue->ref.fit + delta2; 677 678 FT_TRACE5(( ">> activating blue zone %d:" 679 " ref.cur=%.2g ref.fit=%.2g" 680 " shoot.cur=%.2g shoot.fit=%.2g\n", 681 nn, blue->ref.cur / 64.0, blue->ref.fit / 64.0, 682 blue->shoot.cur / 64.0, blue->shoot.fit / 64.0 )); 683 684 blue->flags |= AF_LATIN_BLUE_ACTIVE; 685 } 686 } 687 } 688 } 689 690 691 FT_LOCAL_DEF( void ) 692 af_latin2_metrics_scale( AF_LatinMetrics metrics, 693 AF_Scaler scaler ) 694 { 695 metrics->root.scaler.render_mode = scaler->render_mode; 696 metrics->root.scaler.face = scaler->face; 697 metrics->root.scaler.flags = scaler->flags; 698 699 af_latin2_metrics_scale_dim( metrics, scaler, AF_DIMENSION_HORZ ); 700 af_latin2_metrics_scale_dim( metrics, scaler, AF_DIMENSION_VERT ); 701 } 702 703 704 /* Extract standard_width from writing system/script specific */ 705 /* metrics class. */ 706 707 FT_LOCAL_DEF( void ) 708 af_latin2_get_standard_widths( AF_LatinMetrics metrics, 709 FT_Pos* stdHW, 710 FT_Pos* stdVW ) 711 { 712 if ( stdHW ) 713 *stdHW = metrics->axis[AF_DIMENSION_VERT].standard_width; 714 715 if ( stdVW ) 716 *stdVW = metrics->axis[AF_DIMENSION_HORZ].standard_width; 717 } 718 719 720 /*************************************************************************/ 721 /*************************************************************************/ 722 /***** *****/ 723 /***** L A T I N G L Y P H A N A L Y S I S *****/ 724 /***** *****/ 725 /*************************************************************************/ 726 /*************************************************************************/ 727 728 #define SORT_SEGMENTS 729 730 FT_LOCAL_DEF( FT_Error ) 731 af_latin2_hints_compute_segments( AF_GlyphHints hints, 732 AF_Dimension dim ) 733 { 734 AF_AxisHints axis = &hints->axis[dim]; 735 FT_Memory memory = hints->memory; 736 FT_Error error = FT_Err_Ok; 737 AF_Segment segment = NULL; 738 AF_SegmentRec seg0; 739 AF_Point* contour = hints->contours; 740 AF_Point* contour_limit = contour + hints->num_contours; 741 AF_Direction major_dir, segment_dir; 742 743 744 FT_ZERO( &seg0 ); 745 seg0.score = 32000; 746 seg0.flags = AF_EDGE_NORMAL; 747 748 major_dir = (AF_Direction)FT_ABS( axis->major_dir ); 749 segment_dir = major_dir; 750 751 axis->num_segments = 0; 752 753 /* set up (u,v) in each point */ 754 if ( dim == AF_DIMENSION_HORZ ) 755 { 756 AF_Point point = hints->points; 757 AF_Point limit = point + hints->num_points; 758 759 760 for ( ; point < limit; point++ ) 761 { 762 point->u = point->fx; 763 point->v = point->fy; 764 } 765 } 766 else 767 { 768 AF_Point point = hints->points; 769 AF_Point limit = point + hints->num_points; 770 771 772 for ( ; point < limit; point++ ) 773 { 774 point->u = point->fy; 775 point->v = point->fx; 776 } 777 } 778 779 /* do each contour separately */ 780 for ( ; contour < contour_limit; contour++ ) 781 { 782 AF_Point point = contour[0]; 783 AF_Point start = point; 784 AF_Point last = point->prev; 785 786 787 if ( point == last ) /* skip singletons -- just in case */ 788 continue; 789 790 /* already on an edge ?, backtrack to find its start */ 791 if ( FT_ABS( point->in_dir ) == major_dir ) 792 { 793 point = point->prev; 794 795 while ( point->in_dir == start->in_dir ) 796 point = point->prev; 797 } 798 else /* otherwise, find first segment start, if any */ 799 { 800 while ( FT_ABS( point->out_dir ) != major_dir ) 801 { 802 point = point->next; 803 804 if ( point == start ) 805 goto NextContour; 806 } 807 } 808 809 start = point; 810 811 for (;;) 812 { 813 AF_Point first; 814 FT_Pos min_u, min_v, max_u, max_v; 815 816 /* we're at the start of a new segment */ 817 FT_ASSERT( FT_ABS( point->out_dir ) == major_dir && 818 point->in_dir != point->out_dir ); 819 first = point; 820 821 min_u = max_u = point->u; 822 min_v = max_v = point->v; 823 824 point = point->next; 825 826 while ( point->out_dir == first->out_dir ) 827 { 828 point = point->next; 829 830 if ( point->u < min_u ) 831 min_u = point->u; 832 833 if ( point->u > max_u ) 834 max_u = point->u; 835 } 836 837 if ( point->v < min_v ) 838 min_v = point->v; 839 840 if ( point->v > max_v ) 841 max_v = point->v; 842 843 /* record new segment */ 844 error = af_axis_hints_new_segment( axis, memory, &segment ); 845 if ( error ) 846 goto Exit; 847 848 segment[0] = seg0; 849 segment->dir = first->out_dir; 850 segment->first = first; 851 segment->last = point; 852 segment->pos = (FT_Short)( ( min_u + max_u ) >> 1 ); 853 segment->min_coord = (FT_Short) min_v; 854 segment->max_coord = (FT_Short) max_v; 855 segment->height = (FT_Short)( max_v - min_v ); 856 857 /* a segment is round if it doesn't have successive */ 858 /* on-curve points. */ 859 { 860 AF_Point pt = first; 861 AF_Point last = point; 862 FT_UInt f0 = pt->flags & AF_FLAG_CONTROL; 863 FT_UInt f1; 864 865 866 segment->flags &= ~AF_EDGE_ROUND; 867 868 for ( ; pt != last; f0 = f1 ) 869 { 870 pt = pt->next; 871 f1 = pt->flags & AF_FLAG_CONTROL; 872 873 if ( !f0 && !f1 ) 874 break; 875 876 if ( pt == last ) 877 segment->flags |= AF_EDGE_ROUND; 878 } 879 } 880 881 /* this can happen in the case of a degenerate contour 882 * e.g. a 2-point vertical contour 883 */ 884 if ( point == start ) 885 break; 886 887 /* jump to the start of the next segment, if any */ 888 while ( FT_ABS( point->out_dir ) != major_dir ) 889 { 890 point = point->next; 891 892 if ( point == start ) 893 goto NextContour; 894 } 895 } 896 897 NextContour: 898 ; 899 } /* contours */ 900 901 /* now slightly increase the height of segments when this makes */ 902 /* sense -- this is used to better detect and ignore serifs */ 903 { 904 AF_Segment segments = axis->segments; 905 AF_Segment segments_end = segments + axis->num_segments; 906 907 908 for ( segment = segments; segment < segments_end; segment++ ) 909 { 910 AF_Point first = segment->first; 911 AF_Point last = segment->last; 912 AF_Point p; 913 FT_Pos first_v = first->v; 914 FT_Pos last_v = last->v; 915 916 917 if ( first_v < last_v ) 918 { 919 p = first->prev; 920 if ( p->v < first_v ) 921 segment->height = (FT_Short)( segment->height + 922 ( ( first_v - p->v ) >> 1 ) ); 923 924 p = last->next; 925 if ( p->v > last_v ) 926 segment->height = (FT_Short)( segment->height + 927 ( ( p->v - last_v ) >> 1 ) ); 928 } 929 else 930 { 931 p = first->prev; 932 if ( p->v > first_v ) 933 segment->height = (FT_Short)( segment->height + 934 ( ( p->v - first_v ) >> 1 ) ); 935 936 p = last->next; 937 if ( p->v < last_v ) 938 segment->height = (FT_Short)( segment->height + 939 ( ( last_v - p->v ) >> 1 ) ); 940 } 941 } 942 } 943 944 #ifdef AF_SORT_SEGMENTS 945 /* place all segments with a negative direction to the start 946 * of the array, used to speed up segment linking later... 947 */ 948 { 949 AF_Segment segments = axis->segments; 950 FT_UInt count = axis->num_segments; 951 FT_UInt ii, jj; 952 953 for ( ii = 0; ii < count; ii++ ) 954 { 955 if ( segments[ii].dir > 0 ) 956 { 957 for ( jj = ii + 1; jj < count; jj++ ) 958 { 959 if ( segments[jj].dir < 0 ) 960 { 961 AF_SegmentRec tmp; 962 963 964 tmp = segments[ii]; 965 segments[ii] = segments[jj]; 966 segments[jj] = tmp; 967 968 break; 969 } 970 } 971 972 if ( jj == count ) 973 break; 974 } 975 } 976 axis->mid_segments = ii; 977 } 978 #endif 979 980 Exit: 981 return error; 982 } 983 984 985 FT_LOCAL_DEF( void ) 986 af_latin2_hints_link_segments( AF_GlyphHints hints, 987 AF_Dimension dim ) 988 { 989 AF_AxisHints axis = &hints->axis[dim]; 990 AF_Segment segments = axis->segments; 991 AF_Segment segment_limit = segments + axis->num_segments; 992 #ifdef AF_SORT_SEGMENTS 993 AF_Segment segment_mid = segments + axis->mid_segments; 994 #endif 995 FT_Pos len_threshold, len_score; 996 AF_Segment seg1, seg2; 997 998 999 len_threshold = AF_LATIN_CONSTANT( hints->metrics, 8 ); 1000 if ( len_threshold == 0 ) 1001 len_threshold = 1; 1002 1003 len_score = AF_LATIN_CONSTANT( hints->metrics, 6000 ); 1004 1005 #ifdef AF_SORT_SEGMENTS 1006 for ( seg1 = segments; seg1 < segment_mid; seg1++ ) 1007 { 1008 if ( seg1->dir != axis->major_dir ) 1009 continue; 1010 1011 for ( seg2 = segment_mid; seg2 < segment_limit; seg2++ ) 1012 #else 1013 /* now compare each segment to the others */ 1014 for ( seg1 = segments; seg1 < segment_limit; seg1++ ) 1015 { 1016 if ( seg1->dir != axis->major_dir ) 1017 continue; 1018 1019 for ( seg2 = segments; seg2 < segment_limit; seg2++ ) 1020 if ( seg1->dir + seg2->dir == 0 && seg2->pos > seg1->pos ) 1021 #endif 1022 { 1023 FT_Pos pos1 = seg1->pos; 1024 FT_Pos pos2 = seg2->pos; 1025 FT_Pos dist = pos2 - pos1; 1026 1027 1028 if ( dist < 0 ) 1029 continue; 1030 1031 { 1032 FT_Pos min = seg1->min_coord; 1033 FT_Pos max = seg1->max_coord; 1034 FT_Pos len, score; 1035 1036 1037 if ( min < seg2->min_coord ) 1038 min = seg2->min_coord; 1039 1040 if ( max > seg2->max_coord ) 1041 max = seg2->max_coord; 1042 1043 len = max - min; 1044 if ( len >= len_threshold ) 1045 { 1046 score = dist + len_score / len; 1047 if ( score < seg1->score ) 1048 { 1049 seg1->score = score; 1050 seg1->link = seg2; 1051 } 1052 1053 if ( score < seg2->score ) 1054 { 1055 seg2->score = score; 1056 seg2->link = seg1; 1057 } 1058 } 1059 } 1060 } 1061 } 1062 #if 0 1063 } 1064 #endif 1065 1066 /* now, compute the `serif' segments */ 1067 for ( seg1 = segments; seg1 < segment_limit; seg1++ ) 1068 { 1069 seg2 = seg1->link; 1070 1071 if ( seg2 ) 1072 { 1073 if ( seg2->link != seg1 ) 1074 { 1075 seg1->link = NULL; 1076 seg1->serif = seg2->link; 1077 } 1078 } 1079 } 1080 } 1081 1082 1083 FT_LOCAL_DEF( FT_Error ) 1084 af_latin2_hints_compute_edges( AF_GlyphHints hints, 1085 AF_Dimension dim ) 1086 { 1087 AF_AxisHints axis = &hints->axis[dim]; 1088 FT_Error error = FT_Err_Ok; 1089 FT_Memory memory = hints->memory; 1090 AF_LatinAxis laxis = &((AF_LatinMetrics)hints->metrics)->axis[dim]; 1091 1092 AF_Segment segments = axis->segments; 1093 AF_Segment segment_limit = segments + axis->num_segments; 1094 AF_Segment seg; 1095 1096 AF_Direction up_dir; 1097 FT_Fixed scale; 1098 FT_Pos edge_distance_threshold; 1099 FT_Pos segment_length_threshold; 1100 1101 1102 axis->num_edges = 0; 1103 1104 scale = ( dim == AF_DIMENSION_HORZ ) ? hints->x_scale 1105 : hints->y_scale; 1106 1107 up_dir = ( dim == AF_DIMENSION_HORZ ) ? AF_DIR_UP 1108 : AF_DIR_RIGHT; 1109 1110 /* 1111 * We want to ignore very small (mostly serif) segments, we do that 1112 * by ignoring those that whose length is less than a given fraction 1113 * of the standard width. If there is no standard width, we ignore 1114 * those that are less than a given size in pixels 1115 * 1116 * also, unlink serif segments that are linked to segments farther 1117 * than 50% of the standard width 1118 */ 1119 if ( dim == AF_DIMENSION_HORZ ) 1120 { 1121 if ( laxis->width_count > 0 ) 1122 segment_length_threshold = ( laxis->standard_width * 10 ) >> 4; 1123 else 1124 segment_length_threshold = FT_DivFix( 64, hints->y_scale ); 1125 } 1126 else 1127 segment_length_threshold = 0; 1128 1129 /*********************************************************************/ 1130 /* */ 1131 /* We will begin by generating a sorted table of edges for the */ 1132 /* current direction. To do so, we simply scan each segment and try */ 1133 /* to find an edge in our table that corresponds to its position. */ 1134 /* */ 1135 /* If no edge is found, we create and insert a new edge in the */ 1136 /* sorted table. Otherwise, we simply add the segment to the edge's */ 1137 /* list which will be processed in the second step to compute the */ 1138 /* edge's properties. */ 1139 /* */ 1140 /* Note that the edges table is sorted along the segment/edge */ 1141 /* position. */ 1142 /* */ 1143 /*********************************************************************/ 1144 1145 edge_distance_threshold = FT_MulFix( laxis->edge_distance_threshold, 1146 scale ); 1147 if ( edge_distance_threshold > 64 / 4 ) 1148 edge_distance_threshold = 64 / 4; 1149 1150 edge_distance_threshold = FT_DivFix( edge_distance_threshold, 1151 scale ); 1152 1153 for ( seg = segments; seg < segment_limit; seg++ ) 1154 { 1155 AF_Edge found = NULL; 1156 FT_Int ee; 1157 1158 1159 if ( seg->height < segment_length_threshold ) 1160 continue; 1161 1162 /* A special case for serif edges: If they are smaller than */ 1163 /* 1.5 pixels we ignore them. */ 1164 if ( seg->serif ) 1165 { 1166 FT_Pos dist = seg->serif->pos - seg->pos; 1167 1168 1169 if ( dist < 0 ) 1170 dist = -dist; 1171 1172 if ( dist >= laxis->standard_width >> 1 ) 1173 { 1174 /* unlink this serif, it is too distant from its reference stem */ 1175 seg->serif = NULL; 1176 } 1177 else if ( 2*seg->height < 3 * segment_length_threshold ) 1178 continue; 1179 } 1180 1181 /* look for an edge corresponding to the segment */ 1182 for ( ee = 0; ee < axis->num_edges; ee++ ) 1183 { 1184 AF_Edge edge = axis->edges + ee; 1185 FT_Pos dist; 1186 1187 1188 dist = seg->pos - edge->fpos; 1189 if ( dist < 0 ) 1190 dist = -dist; 1191 1192 if ( dist < edge_distance_threshold && edge->dir == seg->dir ) 1193 { 1194 found = edge; 1195 break; 1196 } 1197 } 1198 1199 if ( !found ) 1200 { 1201 AF_Edge edge; 1202 1203 1204 /* insert a new edge in the list and */ 1205 /* sort according to the position */ 1206 error = af_axis_hints_new_edge( axis, seg->pos, seg->dir, 0, 1207 memory, &edge ); 1208 if ( error ) 1209 goto Exit; 1210 1211 /* add the segment to the new edge's list */ 1212 FT_ZERO( edge ); 1213 1214 edge->first = seg; 1215 edge->last = seg; 1216 edge->dir = seg->dir; 1217 edge->fpos = seg->pos; 1218 edge->opos = FT_MulFix( seg->pos, scale ); 1219 edge->pos = edge->opos; 1220 seg->edge_next = seg; 1221 } 1222 else 1223 { 1224 /* if an edge was found, simply add the segment to the edge's */ 1225 /* list */ 1226 seg->edge_next = found->first; 1227 found->last->edge_next = seg; 1228 found->last = seg; 1229 } 1230 } 1231 1232 1233 /*********************************************************************/ 1234 /* */ 1235 /* Good, we will now compute each edge's properties according to */ 1236 /* segments found on its position. Basically, these are: */ 1237 /* */ 1238 /* - edge's main direction */ 1239 /* - stem edge, serif edge or both (which defaults to stem then) */ 1240 /* - rounded edge, straight or both (which defaults to straight) */ 1241 /* - link for edge */ 1242 /* */ 1243 /*********************************************************************/ 1244 1245 /* first of all, set the `edge' field in each segment -- this is */ 1246 /* required in order to compute edge links */ 1247 1248 /* 1249 * Note that removing this loop and setting the `edge' field of each 1250 * segment directly in the code above slows down execution speed for 1251 * some reasons on platforms like the Sun. 1252 */ 1253 { 1254 AF_Edge edges = axis->edges; 1255 AF_Edge edge_limit = edges + axis->num_edges; 1256 AF_Edge edge; 1257 1258 1259 for ( edge = edges; edge < edge_limit; edge++ ) 1260 { 1261 seg = edge->first; 1262 if ( seg ) 1263 do 1264 { 1265 seg->edge = edge; 1266 seg = seg->edge_next; 1267 1268 } while ( seg != edge->first ); 1269 } 1270 1271 /* now, compute each edge properties */ 1272 for ( edge = edges; edge < edge_limit; edge++ ) 1273 { 1274 FT_Int is_round = 0; /* does it contain round segments? */ 1275 FT_Int is_straight = 0; /* does it contain straight segments? */ 1276 #if 0 1277 FT_Pos ups = 0; /* number of upwards segments */ 1278 FT_Pos downs = 0; /* number of downwards segments */ 1279 #endif 1280 1281 1282 seg = edge->first; 1283 1284 do 1285 { 1286 FT_Bool is_serif; 1287 1288 1289 /* check for roundness of segment */ 1290 if ( seg->flags & AF_EDGE_ROUND ) 1291 is_round++; 1292 else 1293 is_straight++; 1294 1295 #if 0 1296 /* check for segment direction */ 1297 if ( seg->dir == up_dir ) 1298 ups += seg->max_coord-seg->min_coord; 1299 else 1300 downs += seg->max_coord-seg->min_coord; 1301 #endif 1302 1303 /* check for links -- if seg->serif is set, then seg->link must */ 1304 /* be ignored */ 1305 is_serif = (FT_Bool)( seg->serif && 1306 seg->serif->edge && 1307 seg->serif->edge != edge ); 1308 1309 if ( ( seg->link && seg->link->edge ) || is_serif ) 1310 { 1311 AF_Edge edge2; 1312 AF_Segment seg2; 1313 1314 1315 edge2 = edge->link; 1316 seg2 = seg->link; 1317 1318 if ( is_serif ) 1319 { 1320 seg2 = seg->serif; 1321 edge2 = edge->serif; 1322 } 1323 1324 if ( edge2 ) 1325 { 1326 FT_Pos edge_delta; 1327 FT_Pos seg_delta; 1328 1329 1330 edge_delta = edge->fpos - edge2->fpos; 1331 if ( edge_delta < 0 ) 1332 edge_delta = -edge_delta; 1333 1334 seg_delta = seg->pos - seg2->pos; 1335 if ( seg_delta < 0 ) 1336 seg_delta = -seg_delta; 1337 1338 if ( seg_delta < edge_delta ) 1339 edge2 = seg2->edge; 1340 } 1341 else 1342 edge2 = seg2->edge; 1343 1344 if ( is_serif ) 1345 { 1346 edge->serif = edge2; 1347 edge2->flags |= AF_EDGE_SERIF; 1348 } 1349 else 1350 edge->link = edge2; 1351 } 1352 1353 seg = seg->edge_next; 1354 1355 } while ( seg != edge->first ); 1356 1357 /* set the round/straight flags */ 1358 edge->flags = AF_EDGE_NORMAL; 1359 1360 if ( is_round > 0 && is_round >= is_straight ) 1361 edge->flags |= AF_EDGE_ROUND; 1362 1363 #if 0 1364 /* set the edge's main direction */ 1365 edge->dir = AF_DIR_NONE; 1366 1367 if ( ups > downs ) 1368 edge->dir = (FT_Char)up_dir; 1369 1370 else if ( ups < downs ) 1371 edge->dir = (FT_Char)-up_dir; 1372 1373 else if ( ups == downs ) 1374 edge->dir = 0; /* both up and down! */ 1375 #endif 1376 1377 /* gets rid of serifs if link is set */ 1378 /* XXX: This gets rid of many unpleasant artefacts! */ 1379 /* Example: the `c' in cour.pfa at size 13 */ 1380 1381 if ( edge->serif && edge->link ) 1382 edge->serif = NULL; 1383 } 1384 } 1385 1386 Exit: 1387 return error; 1388 } 1389 1390 1391 FT_LOCAL_DEF( FT_Error ) 1392 af_latin2_hints_detect_features( AF_GlyphHints hints, 1393 AF_Dimension dim ) 1394 { 1395 FT_Error error; 1396 1397 1398 error = af_latin2_hints_compute_segments( hints, dim ); 1399 if ( !error ) 1400 { 1401 af_latin2_hints_link_segments( hints, dim ); 1402 1403 error = af_latin2_hints_compute_edges( hints, dim ); 1404 } 1405 return error; 1406 } 1407 1408 1409 static void 1410 af_latin2_hints_compute_blue_edges( AF_GlyphHints hints, 1411 AF_LatinMetrics metrics ) 1412 { 1413 AF_AxisHints axis = &hints->axis[AF_DIMENSION_VERT]; 1414 AF_Edge edge = axis->edges; 1415 AF_Edge edge_limit = edge + axis->num_edges; 1416 AF_LatinAxis latin = &metrics->axis[AF_DIMENSION_VERT]; 1417 FT_Fixed scale = latin->scale; 1418 FT_Pos best_dist0; /* initial threshold */ 1419 1420 1421 /* compute the initial threshold as a fraction of the EM size */ 1422 best_dist0 = FT_MulFix( metrics->units_per_em / 40, scale ); 1423 1424 if ( best_dist0 > 64 / 2 ) 1425 best_dist0 = 64 / 2; 1426 1427 /* compute which blue zones are active, i.e. have their scaled */ 1428 /* size < 3/4 pixels */ 1429 1430 /* for each horizontal edge search the blue zone which is closest */ 1431 for ( ; edge < edge_limit; edge++ ) 1432 { 1433 FT_Int bb; 1434 AF_Width best_blue = NULL; 1435 FT_Pos best_dist = best_dist0; 1436 1437 for ( bb = 0; bb < AF_LATIN_BLUE_MAX; bb++ ) 1438 { 1439 AF_LatinBlue blue = latin->blues + bb; 1440 FT_Bool is_top_blue, is_major_dir; 1441 1442 1443 /* skip inactive blue zones (i.e., those that are too small) */ 1444 if ( !( blue->flags & AF_LATIN_BLUE_ACTIVE ) ) 1445 continue; 1446 1447 /* if it is a top zone, check for right edges -- if it is a bottom */ 1448 /* zone, check for left edges */ 1449 /* */ 1450 /* of course, that's for TrueType */ 1451 is_top_blue = (FT_Byte)( ( blue->flags & AF_LATIN_BLUE_TOP ) != 0 ); 1452 is_major_dir = FT_BOOL( edge->dir == axis->major_dir ); 1453 1454 /* if it is a top zone, the edge must be against the major */ 1455 /* direction; if it is a bottom zone, it must be in the major */ 1456 /* direction */ 1457 if ( is_top_blue ^ is_major_dir ) 1458 { 1459 FT_Pos dist; 1460 AF_Width compare; 1461 1462 1463 /* if it's a rounded edge, compare it to the overshoot position */ 1464 /* if it's a flat edge, compare it to the reference position */ 1465 if ( edge->flags & AF_EDGE_ROUND ) 1466 compare = &blue->shoot; 1467 else 1468 compare = &blue->ref; 1469 1470 dist = edge->fpos - compare->org; 1471 if ( dist < 0 ) 1472 dist = -dist; 1473 1474 dist = FT_MulFix( dist, scale ); 1475 if ( dist < best_dist ) 1476 { 1477 best_dist = dist; 1478 best_blue = compare; 1479 } 1480 1481 #if 0 1482 /* now, compare it to the overshoot position if the edge is */ 1483 /* rounded, and if the edge is over the reference position of a */ 1484 /* top zone, or under the reference position of a bottom zone */ 1485 if ( edge->flags & AF_EDGE_ROUND && dist != 0 ) 1486 { 1487 FT_Bool is_under_ref = FT_BOOL( edge->fpos < blue->ref.org ); 1488 1489 1490 if ( is_top_blue ^ is_under_ref ) 1491 { 1492 blue = latin->blues + bb; 1493 dist = edge->fpos - blue->shoot.org; 1494 if ( dist < 0 ) 1495 dist = -dist; 1496 1497 dist = FT_MulFix( dist, scale ); 1498 if ( dist < best_dist ) 1499 { 1500 best_dist = dist; 1501 best_blue = & blue->shoot; 1502 } 1503 } 1504 } 1505 #endif 1506 } 1507 } 1508 1509 if ( best_blue ) 1510 edge->blue_edge = best_blue; 1511 } 1512 } 1513 1514 1515 static FT_Error 1516 af_latin2_hints_init( AF_GlyphHints hints, 1517 AF_LatinMetrics metrics ) 1518 { 1519 FT_Render_Mode mode; 1520 FT_UInt32 scaler_flags, other_flags; 1521 FT_Face face = metrics->root.scaler.face; 1522 1523 1524 af_glyph_hints_rescale( hints, (AF_StyleMetrics)metrics ); 1525 1526 /* 1527 * correct x_scale and y_scale if needed, since they may have 1528 * been modified `af_latin2_metrics_scale_dim' above 1529 */ 1530 hints->x_scale = metrics->axis[AF_DIMENSION_HORZ].scale; 1531 hints->x_delta = metrics->axis[AF_DIMENSION_HORZ].delta; 1532 hints->y_scale = metrics->axis[AF_DIMENSION_VERT].scale; 1533 hints->y_delta = metrics->axis[AF_DIMENSION_VERT].delta; 1534 1535 /* compute flags depending on render mode, etc. */ 1536 mode = metrics->root.scaler.render_mode; 1537 1538 #if 0 /* #ifdef AF_CONFIG_OPTION_USE_WARPER */ 1539 if ( mode == FT_RENDER_MODE_LCD || mode == FT_RENDER_MODE_LCD_V ) 1540 metrics->root.scaler.render_mode = mode = FT_RENDER_MODE_NORMAL; 1541 #endif 1542 1543 scaler_flags = hints->scaler_flags; 1544 other_flags = 0; 1545 1546 /* 1547 * We snap the width of vertical stems for the monochrome and 1548 * horizontal LCD rendering targets only. 1549 */ 1550 if ( mode == FT_RENDER_MODE_MONO || mode == FT_RENDER_MODE_LCD ) 1551 other_flags |= AF_LATIN_HINTS_HORZ_SNAP; 1552 1553 /* 1554 * We snap the width of horizontal stems for the monochrome and 1555 * vertical LCD rendering targets only. 1556 */ 1557 if ( mode == FT_RENDER_MODE_MONO || mode == FT_RENDER_MODE_LCD_V ) 1558 other_flags |= AF_LATIN_HINTS_VERT_SNAP; 1559 1560 /* 1561 * We adjust stems to full pixels unless in `light' or `lcd' mode. 1562 */ 1563 if ( mode != FT_RENDER_MODE_LIGHT && mode != FT_RENDER_MODE_LCD ) 1564 other_flags |= AF_LATIN_HINTS_STEM_ADJUST; 1565 1566 if ( mode == FT_RENDER_MODE_MONO ) 1567 other_flags |= AF_LATIN_HINTS_MONO; 1568 1569 /* 1570 * In `light' or `lcd' mode we disable horizontal hinting completely. 1571 * We also do it if the face is italic. 1572 */ 1573 if ( mode == FT_RENDER_MODE_LIGHT || mode == FT_RENDER_MODE_LCD || 1574 ( face->style_flags & FT_STYLE_FLAG_ITALIC ) != 0 ) 1575 scaler_flags |= AF_SCALER_FLAG_NO_HORIZONTAL; 1576 1577 #ifdef AF_CONFIG_OPTION_USE_WARPER 1578 /* get (global) warper flag */ 1579 if ( !metrics->root.globals->module->warping ) 1580 scaler_flags |= AF_SCALER_FLAG_NO_WARPER; 1581 #endif 1582 1583 hints->scaler_flags = scaler_flags; 1584 hints->other_flags = other_flags; 1585 1586 return 0; 1587 } 1588 1589 1590 /*************************************************************************/ 1591 /*************************************************************************/ 1592 /***** *****/ 1593 /***** L A T I N G L Y P H G R I D - F I T T I N G *****/ 1594 /***** *****/ 1595 /*************************************************************************/ 1596 /*************************************************************************/ 1597 1598 /* snap a given width in scaled coordinates to one of the */ 1599 /* current standard widths */ 1600 1601 static FT_Pos 1602 af_latin2_snap_width( AF_Width widths, 1603 FT_UInt count, 1604 FT_Pos width ) 1605 { 1606 FT_UInt n; 1607 FT_Pos best = 64 + 32 + 2; 1608 FT_Pos reference = width; 1609 FT_Pos scaled; 1610 1611 1612 for ( n = 0; n < count; n++ ) 1613 { 1614 FT_Pos w; 1615 FT_Pos dist; 1616 1617 1618 w = widths[n].cur; 1619 dist = width - w; 1620 if ( dist < 0 ) 1621 dist = -dist; 1622 if ( dist < best ) 1623 { 1624 best = dist; 1625 reference = w; 1626 } 1627 } 1628 1629 scaled = FT_PIX_ROUND( reference ); 1630 1631 if ( width >= reference ) 1632 { 1633 if ( width < scaled + 48 ) 1634 width = reference; 1635 } 1636 else 1637 { 1638 if ( width > scaled - 48 ) 1639 width = reference; 1640 } 1641 1642 return width; 1643 } 1644 1645 1646 /* compute the snapped width of a given stem */ 1647 1648 static FT_Pos 1649 af_latin2_compute_stem_width( AF_GlyphHints hints, 1650 AF_Dimension dim, 1651 FT_Pos width, 1652 FT_UInt base_flags, 1653 FT_UInt stem_flags ) 1654 { 1655 AF_LatinMetrics metrics = (AF_LatinMetrics) hints->metrics; 1656 AF_LatinAxis axis = & metrics->axis[dim]; 1657 FT_Pos dist = width; 1658 FT_Int sign = 0; 1659 FT_Int vertical = ( dim == AF_DIMENSION_VERT ); 1660 1661 FT_UNUSED( base_flags ); 1662 1663 1664 if ( !AF_LATIN_HINTS_DO_STEM_ADJUST( hints ) || 1665 axis->extra_light ) 1666 return width; 1667 1668 if ( dist < 0 ) 1669 { 1670 dist = -width; 1671 sign = 1; 1672 } 1673 1674 if ( ( vertical && !AF_LATIN_HINTS_DO_VERT_SNAP( hints ) ) || 1675 ( !vertical && !AF_LATIN_HINTS_DO_HORZ_SNAP( hints ) ) ) 1676 { 1677 /* smooth hinting process: very lightly quantize the stem width */ 1678 1679 /* leave the widths of serifs alone */ 1680 1681 if ( ( stem_flags & AF_EDGE_SERIF ) && vertical && ( dist < 3 * 64 ) ) 1682 goto Done_Width; 1683 1684 #if 0 1685 else if ( ( base_flags & AF_EDGE_ROUND ) ) 1686 { 1687 if ( dist < 80 ) 1688 dist = 64; 1689 } 1690 else if ( dist < 56 ) 1691 dist = 56; 1692 #endif 1693 if ( axis->width_count > 0 ) 1694 { 1695 FT_Pos delta; 1696 1697 1698 /* compare to standard width */ 1699 if ( axis->width_count > 0 ) 1700 { 1701 delta = dist - axis->widths[0].cur; 1702 1703 if ( delta < 0 ) 1704 delta = -delta; 1705 1706 if ( delta < 40 ) 1707 { 1708 dist = axis->widths[0].cur; 1709 if ( dist < 48 ) 1710 dist = 48; 1711 1712 goto Done_Width; 1713 } 1714 } 1715 1716 if ( dist < 3 * 64 ) 1717 { 1718 delta = dist & 63; 1719 dist &= -64; 1720 1721 if ( delta < 10 ) 1722 dist += delta; 1723 1724 else if ( delta < 32 ) 1725 dist += 10; 1726 1727 else if ( delta < 54 ) 1728 dist += 54; 1729 1730 else 1731 dist += delta; 1732 } 1733 else 1734 dist = ( dist + 32 ) & ~63; 1735 } 1736 } 1737 else 1738 { 1739 /* strong hinting process: snap the stem width to integer pixels */ 1740 FT_Pos org_dist = dist; 1741 1742 1743 dist = af_latin2_snap_width( axis->widths, axis->width_count, dist ); 1744 1745 if ( vertical ) 1746 { 1747 /* in the case of vertical hinting, always round */ 1748 /* the stem heights to integer pixels */ 1749 1750 if ( dist >= 64 ) 1751 dist = ( dist + 16 ) & ~63; 1752 else 1753 dist = 64; 1754 } 1755 else 1756 { 1757 if ( AF_LATIN_HINTS_DO_MONO( hints ) ) 1758 { 1759 /* monochrome horizontal hinting: snap widths to integer pixels */ 1760 /* with a different threshold */ 1761 1762 if ( dist < 64 ) 1763 dist = 64; 1764 else 1765 dist = ( dist + 32 ) & ~63; 1766 } 1767 else 1768 { 1769 /* for horizontal anti-aliased hinting, we adopt a more subtle */ 1770 /* approach: we strengthen small stems, round stems whose size */ 1771 /* is between 1 and 2 pixels to an integer, otherwise nothing */ 1772 1773 if ( dist < 48 ) 1774 dist = ( dist + 64 ) >> 1; 1775 1776 else if ( dist < 128 ) 1777 { 1778 /* We only round to an integer width if the corresponding */ 1779 /* distortion is less than 1/4 pixel. Otherwise this */ 1780 /* makes everything worse since the diagonals, which are */ 1781 /* not hinted, appear a lot bolder or thinner than the */ 1782 /* vertical stems. */ 1783 1784 FT_Int delta; 1785 1786 1787 dist = ( dist + 22 ) & ~63; 1788 delta = dist - org_dist; 1789 if ( delta < 0 ) 1790 delta = -delta; 1791 1792 if ( delta >= 16 ) 1793 { 1794 dist = org_dist; 1795 if ( dist < 48 ) 1796 dist = ( dist + 64 ) >> 1; 1797 } 1798 } 1799 else 1800 /* round otherwise to prevent color fringes in LCD mode */ 1801 dist = ( dist + 32 ) & ~63; 1802 } 1803 } 1804 } 1805 1806 Done_Width: 1807 if ( sign ) 1808 dist = -dist; 1809 1810 return dist; 1811 } 1812 1813 1814 /* align one stem edge relative to the previous stem edge */ 1815 1816 static void 1817 af_latin2_align_linked_edge( AF_GlyphHints hints, 1818 AF_Dimension dim, 1819 AF_Edge base_edge, 1820 AF_Edge stem_edge ) 1821 { 1822 FT_Pos dist = stem_edge->opos - base_edge->opos; 1823 1824 FT_Pos fitted_width = af_latin2_compute_stem_width( hints, dim, dist, 1825 base_edge->flags, 1826 stem_edge->flags ); 1827 1828 1829 stem_edge->pos = base_edge->pos + fitted_width; 1830 1831 FT_TRACE5(( "LINK: edge %d (opos=%.2f) linked to (%.2f), " 1832 "dist was %.2f, now %.2f\n", 1833 stem_edge-hints->axis[dim].edges, stem_edge->opos / 64.0, 1834 stem_edge->pos / 64.0, dist / 64.0, fitted_width / 64.0 )); 1835 } 1836 1837 1838 static void 1839 af_latin2_align_serif_edge( AF_GlyphHints hints, 1840 AF_Edge base, 1841 AF_Edge serif ) 1842 { 1843 FT_UNUSED( hints ); 1844 1845 serif->pos = base->pos + ( serif->opos - base->opos ); 1846 } 1847 1848 1849 /*************************************************************************/ 1850 /*************************************************************************/ 1851 /*************************************************************************/ 1852 /**** ****/ 1853 /**** E D G E H I N T I N G ****/ 1854 /**** ****/ 1855 /*************************************************************************/ 1856 /*************************************************************************/ 1857 /*************************************************************************/ 1858 1859 1860 static void 1861 af_latin2_hint_edges( AF_GlyphHints hints, 1862 AF_Dimension dim ) 1863 { 1864 AF_AxisHints axis = &hints->axis[dim]; 1865 AF_Edge edges = axis->edges; 1866 AF_Edge edge_limit = edges + axis->num_edges; 1867 AF_Edge edge; 1868 AF_Edge anchor = NULL; 1869 FT_Int has_serifs = 0; 1870 FT_Pos anchor_drift = 0; 1871 1872 1873 1874 FT_TRACE5(( "==== hinting %s edges =====\n", 1875 dim == AF_DIMENSION_HORZ ? "vertical" : "horizontal" )); 1876 1877 /* we begin by aligning all stems relative to the blue zone */ 1878 /* if needed -- that's only for horizontal edges */ 1879 1880 if ( dim == AF_DIMENSION_VERT && AF_HINTS_DO_BLUES( hints ) ) 1881 { 1882 for ( edge = edges; edge < edge_limit; edge++ ) 1883 { 1884 AF_Width blue; 1885 AF_Edge edge1, edge2; 1886 1887 1888 if ( edge->flags & AF_EDGE_DONE ) 1889 continue; 1890 1891 blue = edge->blue_edge; 1892 edge1 = NULL; 1893 edge2 = edge->link; 1894 1895 if ( blue ) 1896 { 1897 edge1 = edge; 1898 } 1899 else if ( edge2 && edge2->blue_edge ) 1900 { 1901 blue = edge2->blue_edge; 1902 edge1 = edge2; 1903 edge2 = edge; 1904 } 1905 1906 if ( !edge1 ) 1907 continue; 1908 1909 FT_TRACE5(( "BLUE: edge %d (opos=%.2f) snapped to (%.2f), " 1910 "was (%.2f)\n", 1911 edge1-edges, edge1->opos / 64.0, blue->fit / 64.0, 1912 edge1->pos / 64.0 )); 1913 1914 edge1->pos = blue->fit; 1915 edge1->flags |= AF_EDGE_DONE; 1916 1917 if ( edge2 && !edge2->blue_edge ) 1918 { 1919 af_latin2_align_linked_edge( hints, dim, edge1, edge2 ); 1920 edge2->flags |= AF_EDGE_DONE; 1921 } 1922 1923 if ( !anchor ) 1924 { 1925 anchor = edge; 1926 1927 anchor_drift = ( anchor->pos - anchor->opos ); 1928 if ( edge2 ) 1929 anchor_drift = ( anchor_drift + 1930 ( edge2->pos - edge2->opos ) ) >> 1; 1931 } 1932 } 1933 } 1934 1935 /* now we will align all stem edges, trying to maintain the */ 1936 /* relative order of stems in the glyph */ 1937 for ( edge = edges; edge < edge_limit; edge++ ) 1938 { 1939 AF_Edge edge2; 1940 1941 1942 if ( edge->flags & AF_EDGE_DONE ) 1943 continue; 1944 1945 /* skip all non-stem edges */ 1946 edge2 = edge->link; 1947 if ( !edge2 ) 1948 { 1949 has_serifs++; 1950 continue; 1951 } 1952 1953 /* now align the stem */ 1954 1955 /* this should not happen, but it's better to be safe */ 1956 if ( edge2->blue_edge ) 1957 { 1958 FT_TRACE5(( "ASSERTION FAILED for edge %d\n", edge2-edges )); 1959 1960 af_latin2_align_linked_edge( hints, dim, edge2, edge ); 1961 edge->flags |= AF_EDGE_DONE; 1962 continue; 1963 } 1964 1965 if ( !anchor ) 1966 { 1967 FT_Pos org_len, org_center, cur_len; 1968 FT_Pos cur_pos1, error1, error2, u_off, d_off; 1969 1970 1971 org_len = edge2->opos - edge->opos; 1972 cur_len = af_latin2_compute_stem_width( hints, dim, org_len, 1973 edge->flags, 1974 edge2->flags ); 1975 if ( cur_len <= 64 ) 1976 u_off = d_off = 32; 1977 else 1978 { 1979 u_off = 38; 1980 d_off = 26; 1981 } 1982 1983 if ( cur_len < 96 ) 1984 { 1985 org_center = edge->opos + ( org_len >> 1 ); 1986 1987 cur_pos1 = FT_PIX_ROUND( org_center ); 1988 1989 error1 = org_center - ( cur_pos1 - u_off ); 1990 if ( error1 < 0 ) 1991 error1 = -error1; 1992 1993 error2 = org_center - ( cur_pos1 + d_off ); 1994 if ( error2 < 0 ) 1995 error2 = -error2; 1996 1997 if ( error1 < error2 ) 1998 cur_pos1 -= u_off; 1999 else 2000 cur_pos1 += d_off; 2001 2002 edge->pos = cur_pos1 - cur_len / 2; 2003 edge2->pos = edge->pos + cur_len; 2004 } 2005 else 2006 edge->pos = FT_PIX_ROUND( edge->opos ); 2007 2008 FT_TRACE5(( "ANCHOR: edge %d (opos=%.2f) and %d (opos=%.2f)" 2009 " snapped to (%.2f) (%.2f)\n", 2010 edge-edges, edge->opos / 64.0, 2011 edge2-edges, edge2->opos / 64.0, 2012 edge->pos / 64.0, edge2->pos / 64.0 )); 2013 anchor = edge; 2014 2015 edge->flags |= AF_EDGE_DONE; 2016 2017 af_latin2_align_linked_edge( hints, dim, edge, edge2 ); 2018 2019 edge2->flags |= AF_EDGE_DONE; 2020 2021 anchor_drift = ( ( anchor->pos - anchor->opos ) + 2022 ( edge2->pos - edge2->opos ) ) >> 1; 2023 2024 FT_TRACE5(( "DRIFT: %.2f\n", anchor_drift/64.0 )); 2025 } 2026 else 2027 { 2028 FT_Pos org_pos, org_len, org_center, cur_center, cur_len; 2029 FT_Pos org_left, org_right; 2030 2031 2032 org_pos = edge->opos + anchor_drift; 2033 org_len = edge2->opos - edge->opos; 2034 org_center = org_pos + ( org_len >> 1 ); 2035 2036 cur_len = af_latin2_compute_stem_width( hints, dim, org_len, 2037 edge->flags, 2038 edge2->flags ); 2039 2040 org_left = org_pos + ( ( org_len - cur_len ) >> 1 ); 2041 org_right = org_pos + ( ( org_len + cur_len ) >> 1 ); 2042 2043 FT_TRACE5(( "ALIGN: left=%.2f right=%.2f ", 2044 org_left / 64.0, org_right / 64.0 )); 2045 cur_center = org_center; 2046 2047 if ( edge2->flags & AF_EDGE_DONE ) 2048 { 2049 FT_TRACE5(( "\n" )); 2050 edge->pos = edge2->pos - cur_len; 2051 } 2052 else 2053 { 2054 /* we want to compare several displacement, and choose 2055 * the one that increases fitness while minimizing 2056 * distortion as well 2057 */ 2058 FT_Pos displacements[6], scores[6], org, fit, delta; 2059 FT_UInt count = 0; 2060 2061 /* note: don't even try to fit tiny stems */ 2062 if ( cur_len < 32 ) 2063 { 2064 FT_TRACE5(( "tiny stem\n" )); 2065 goto AlignStem; 2066 } 2067 2068 /* if the span is within a single pixel, don't touch it */ 2069 if ( FT_PIX_FLOOR( org_left ) == FT_PIX_CEIL( org_right ) ) 2070 { 2071 FT_TRACE5(( "single pixel stem\n" )); 2072 goto AlignStem; 2073 } 2074 2075 if ( cur_len <= 96 ) 2076 { 2077 /* we want to avoid the absolute worst case which is 2078 * when the left and right edges of the span each represent 2079 * about 50% of the gray. we'd better want to change this 2080 * to 25/75%, since this is much more pleasant to the eye with 2081 * very acceptable distortion 2082 */ 2083 FT_Pos frac_left = org_left & 63; 2084 FT_Pos frac_right = org_right & 63; 2085 2086 if ( frac_left >= 22 && frac_left <= 42 && 2087 frac_right >= 22 && frac_right <= 42 ) 2088 { 2089 org = frac_left; 2090 fit = ( org <= 32 ) ? 16 : 48; 2091 delta = FT_ABS( fit - org ); 2092 displacements[count] = fit - org; 2093 scores[count++] = delta; 2094 FT_TRACE5(( "dispA=%.2f (%d) ", ( fit - org ) / 64.0, delta )); 2095 2096 org = frac_right; 2097 fit = ( org <= 32 ) ? 16 : 48; 2098 delta = FT_ABS( fit - org ); 2099 displacements[count] = fit - org; 2100 scores[count++] = delta; 2101 FT_TRACE5(( "dispB=%.2f (%d) ", ( fit - org ) / 64.0, delta )); 2102 } 2103 } 2104 2105 /* snapping the left edge to the grid */ 2106 org = org_left; 2107 fit = FT_PIX_ROUND( org ); 2108 delta = FT_ABS( fit - org ); 2109 displacements[count] = fit - org; 2110 scores[count++] = delta; 2111 FT_TRACE5(( "dispC=%.2f (%d) ", ( fit - org ) / 64.0, delta )); 2112 2113 /* snapping the right edge to the grid */ 2114 org = org_right; 2115 fit = FT_PIX_ROUND( org ); 2116 delta = FT_ABS( fit - org ); 2117 displacements[count] = fit - org; 2118 scores[count++] = delta; 2119 FT_TRACE5(( "dispD=%.2f (%d) ", ( fit - org ) / 64.0, delta )); 2120 2121 /* now find the best displacement */ 2122 { 2123 FT_Pos best_score = scores[0]; 2124 FT_Pos best_disp = displacements[0]; 2125 FT_UInt nn; 2126 2127 for ( nn = 1; nn < count; nn++ ) 2128 { 2129 if ( scores[nn] < best_score ) 2130 { 2131 best_score = scores[nn]; 2132 best_disp = displacements[nn]; 2133 } 2134 } 2135 2136 cur_center = org_center + best_disp; 2137 } 2138 FT_TRACE5(( "\n" )); 2139 } 2140 2141 AlignStem: 2142 edge->pos = cur_center - ( cur_len >> 1 ); 2143 edge2->pos = edge->pos + cur_len; 2144 2145 FT_TRACE5(( "STEM1: %d (opos=%.2f) to %d (opos=%.2f)" 2146 " snapped to (%.2f) and (%.2f)," 2147 " org_len=%.2f cur_len=%.2f\n", 2148 edge-edges, edge->opos / 64.0, 2149 edge2-edges, edge2->opos / 64.0, 2150 edge->pos / 64.0, edge2->pos / 64.0, 2151 org_len / 64.0, cur_len / 64.0 )); 2152 2153 edge->flags |= AF_EDGE_DONE; 2154 edge2->flags |= AF_EDGE_DONE; 2155 2156 if ( edge > edges && edge->pos < edge[-1].pos ) 2157 { 2158 FT_TRACE5(( "BOUND: %d (pos=%.2f) to (%.2f)\n", 2159 edge-edges, edge->pos / 64.0, edge[-1].pos / 64.0 )); 2160 edge->pos = edge[-1].pos; 2161 } 2162 } 2163 } 2164 2165 /* make sure that lowercase m's maintain their symmetry */ 2166 2167 /* In general, lowercase m's have six vertical edges if they are sans */ 2168 /* serif, or twelve if they are with serifs. This implementation is */ 2169 /* based on that assumption, and seems to work very well with most */ 2170 /* faces. However, if for a certain face this assumption is not */ 2171 /* true, the m is just rendered like before. In addition, any stem */ 2172 /* correction will only be applied to symmetrical glyphs (even if the */ 2173 /* glyph is not an m), so the potential for unwanted distortion is */ 2174 /* relatively low. */ 2175 2176 /* We don't handle horizontal edges since we can't easily assure that */ 2177 /* the third (lowest) stem aligns with the base line; it might end up */ 2178 /* one pixel higher or lower. */ 2179 2180 #if 0 2181 { 2182 FT_Int n_edges = edge_limit - edges; 2183 2184 2185 if ( dim == AF_DIMENSION_HORZ && ( n_edges == 6 || n_edges == 12 ) ) 2186 { 2187 AF_Edge edge1, edge2, edge3; 2188 FT_Pos dist1, dist2, span, delta; 2189 2190 2191 if ( n_edges == 6 ) 2192 { 2193 edge1 = edges; 2194 edge2 = edges + 2; 2195 edge3 = edges + 4; 2196 } 2197 else 2198 { 2199 edge1 = edges + 1; 2200 edge2 = edges + 5; 2201 edge3 = edges + 9; 2202 } 2203 2204 dist1 = edge2->opos - edge1->opos; 2205 dist2 = edge3->opos - edge2->opos; 2206 2207 span = dist1 - dist2; 2208 if ( span < 0 ) 2209 span = -span; 2210 2211 if ( span < 8 ) 2212 { 2213 delta = edge3->pos - ( 2 * edge2->pos - edge1->pos ); 2214 edge3->pos -= delta; 2215 if ( edge3->link ) 2216 edge3->link->pos -= delta; 2217 2218 /* move the serifs along with the stem */ 2219 if ( n_edges == 12 ) 2220 { 2221 ( edges + 8 )->pos -= delta; 2222 ( edges + 11 )->pos -= delta; 2223 } 2224 2225 edge3->flags |= AF_EDGE_DONE; 2226 if ( edge3->link ) 2227 edge3->link->flags |= AF_EDGE_DONE; 2228 } 2229 } 2230 } 2231 #endif 2232 2233 if ( has_serifs || !anchor ) 2234 { 2235 /* 2236 * now hint the remaining edges (serifs and single) in order 2237 * to complete our processing 2238 */ 2239 for ( edge = edges; edge < edge_limit; edge++ ) 2240 { 2241 FT_Pos delta; 2242 2243 2244 if ( edge->flags & AF_EDGE_DONE ) 2245 continue; 2246 2247 delta = 1000; 2248 2249 if ( edge->serif ) 2250 { 2251 delta = edge->serif->opos - edge->opos; 2252 if ( delta < 0 ) 2253 delta = -delta; 2254 } 2255 2256 if ( delta < 64 + 16 ) 2257 { 2258 af_latin2_align_serif_edge( hints, edge->serif, edge ); 2259 FT_TRACE5(( "SERIF: edge %d (opos=%.2f) serif to %d (opos=%.2f)" 2260 " aligned to (%.2f)\n", 2261 edge-edges, edge->opos / 64.0, 2262 edge->serif - edges, edge->serif->opos / 64.0, 2263 edge->pos / 64.0 )); 2264 } 2265 else if ( !anchor ) 2266 { 2267 FT_TRACE5(( "SERIF_ANCHOR: edge %d (opos=%.2f)" 2268 " snapped to (%.2f)\n", 2269 edge-edges, edge->opos / 64.0, edge->pos / 64.0 )); 2270 edge->pos = FT_PIX_ROUND( edge->opos ); 2271 anchor = edge; 2272 } 2273 else 2274 { 2275 AF_Edge before, after; 2276 2277 2278 for ( before = edge - 1; before >= edges; before-- ) 2279 if ( before->flags & AF_EDGE_DONE ) 2280 break; 2281 2282 for ( after = edge + 1; after < edge_limit; after++ ) 2283 if ( after->flags & AF_EDGE_DONE ) 2284 break; 2285 2286 if ( before >= edges && before < edge && 2287 after < edge_limit && after > edge ) 2288 { 2289 if ( after->opos == before->opos ) 2290 edge->pos = before->pos; 2291 else 2292 edge->pos = before->pos + 2293 FT_MulDiv( edge->opos - before->opos, 2294 after->pos - before->pos, 2295 after->opos - before->opos ); 2296 FT_TRACE5(( "SERIF_LINK1: edge %d (opos=%.2f) snapped to (%.2f)" 2297 " from %d (opos=%.2f)\n", 2298 edge-edges, edge->opos / 64.0, edge->pos / 64.0, 2299 before - edges, before->opos / 64.0 )); 2300 } 2301 else 2302 { 2303 edge->pos = anchor->pos + 2304 ( ( edge->opos - anchor->opos + 16 ) & ~31 ); 2305 2306 FT_TRACE5(( "SERIF_LINK2: edge %d (opos=%.2f)" 2307 " snapped to (%.2f)\n", 2308 edge-edges, edge->opos / 64.0, edge->pos / 64.0 )); 2309 } 2310 } 2311 2312 edge->flags |= AF_EDGE_DONE; 2313 2314 if ( edge > edges && edge->pos < edge[-1].pos ) 2315 edge->pos = edge[-1].pos; 2316 2317 if ( edge + 1 < edge_limit && 2318 edge[1].flags & AF_EDGE_DONE && 2319 edge->pos > edge[1].pos ) 2320 edge->pos = edge[1].pos; 2321 } 2322 } 2323 } 2324 2325 2326 static FT_Error 2327 af_latin2_hints_apply( FT_UInt glyph_index, 2328 AF_GlyphHints hints, 2329 FT_Outline* outline, 2330 AF_LatinMetrics metrics ) 2331 { 2332 FT_Error error; 2333 int dim; 2334 2335 FT_UNUSED( glyph_index ); 2336 2337 2338 error = af_glyph_hints_reload( hints, outline ); 2339 if ( error ) 2340 goto Exit; 2341 2342 /* analyze glyph outline */ 2343 if ( AF_HINTS_DO_HORIZONTAL( hints ) ) 2344 { 2345 error = af_latin2_hints_detect_features( hints, AF_DIMENSION_HORZ ); 2346 if ( error ) 2347 goto Exit; 2348 } 2349 2350 if ( AF_HINTS_DO_VERTICAL( hints ) ) 2351 { 2352 error = af_latin2_hints_detect_features( hints, AF_DIMENSION_VERT ); 2353 if ( error ) 2354 goto Exit; 2355 2356 af_latin2_hints_compute_blue_edges( hints, metrics ); 2357 } 2358 2359 /* grid-fit the outline */ 2360 for ( dim = 0; dim < AF_DIMENSION_MAX; dim++ ) 2361 { 2362 #ifdef AF_CONFIG_OPTION_USE_WARPER 2363 if ( dim == AF_DIMENSION_HORZ && 2364 metrics->root.scaler.render_mode == FT_RENDER_MODE_NORMAL && 2365 AF_HINTS_DO_WARP( hints ) ) 2366 { 2367 AF_WarperRec warper; 2368 FT_Fixed scale; 2369 FT_Pos delta; 2370 2371 2372 af_warper_compute( &warper, hints, dim, &scale, &delta ); 2373 af_glyph_hints_scale_dim( hints, dim, scale, delta ); 2374 continue; 2375 } 2376 #endif /* AF_CONFIG_OPTION_USE_WARPER */ 2377 2378 if ( ( dim == AF_DIMENSION_HORZ && AF_HINTS_DO_HORIZONTAL( hints ) ) || 2379 ( dim == AF_DIMENSION_VERT && AF_HINTS_DO_VERTICAL( hints ) ) ) 2380 { 2381 af_latin2_hint_edges( hints, (AF_Dimension)dim ); 2382 af_glyph_hints_align_edge_points( hints, (AF_Dimension)dim ); 2383 af_glyph_hints_align_strong_points( hints, (AF_Dimension)dim ); 2384 af_glyph_hints_align_weak_points( hints, (AF_Dimension)dim ); 2385 } 2386 } 2387 af_glyph_hints_save( hints, outline ); 2388 2389 Exit: 2390 return error; 2391 } 2392 2393 2394 /*************************************************************************/ 2395 /*************************************************************************/ 2396 /***** *****/ 2397 /***** L A T I N S C R I P T C L A S S *****/ 2398 /***** *****/ 2399 /*************************************************************************/ 2400 /*************************************************************************/ 2401 2402 2403 AF_DEFINE_WRITING_SYSTEM_CLASS( 2404 af_latin2_writing_system_class, 2405 2406 AF_WRITING_SYSTEM_LATIN2, 2407 2408 sizeof ( AF_LatinMetricsRec ), 2409 2410 (AF_WritingSystem_InitMetricsFunc) af_latin2_metrics_init, /* style_metrics_init */ 2411 (AF_WritingSystem_ScaleMetricsFunc)af_latin2_metrics_scale, /* style_metrics_scale */ 2412 (AF_WritingSystem_DoneMetricsFunc) NULL, /* style_metrics_done */ 2413 (AF_WritingSystem_GetStdWidthsFunc)af_latin2_get_standard_widths, /* style_metrics_getstdw */ 2414 2415 (AF_WritingSystem_InitHintsFunc) af_latin2_hints_init, /* style_hints_init */ 2416 (AF_WritingSystem_ApplyHintsFunc) af_latin2_hints_apply /* style_hints_apply */ 2417 ) 2418 2419 #else /* !FT_OPTION_AUTOFIT2 */ 2420 2421 /* ANSI C doesn't like empty source files */ 2422 typedef int _af_latin2_dummy; 2423 2424 #endif /* !FT_OPTION_AUTOFIT2 */ 2425 2426 2427 /* END */ 2428
