1 /***************************************************************************/ 2 /* */ 3 /* aflatin2.c */ 4 /* */ 5 /* Auto-fitter hinting routines for latin writing system (body). */ 6 /* */ 7 /* Copyright 2003-2014 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 FT_ADVANCES_H 20 21 #include "afglobal.h" 22 #include "aflatin.h" 23 #include "aflatin2.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 trace_aflatin2 40 41 42 FT_LOCAL_DEF( FT_Error ) 43 af_latin2_hints_compute_segments( AF_GlyphHints hints, 44 AF_Dimension dim ); 45 46 FT_LOCAL_DEF( void ) 47 af_latin2_hints_link_segments( AF_GlyphHints hints, 48 AF_Dimension dim ); 49 50 /*************************************************************************/ 51 /*************************************************************************/ 52 /***** *****/ 53 /***** L A T I N G L O B A L M E T R I C S *****/ 54 /***** *****/ 55 /*************************************************************************/ 56 /*************************************************************************/ 57 58 FT_LOCAL_DEF( void ) af_latin2_metrics_init_widths(AF_LatinMetrics metrics,FT_Face face)59 af_latin2_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 af_glyph_hints_init( hints, face->memory ); 67 68 metrics->axis[AF_DIMENSION_HORZ].width_count = 0; 69 metrics->axis[AF_DIMENSION_VERT].width_count = 0; 70 71 { 72 FT_Error error; 73 FT_UInt glyph_index; 74 int dim; 75 AF_LatinMetricsRec dummy[1]; 76 AF_Scaler scaler = &dummy->root.scaler; 77 78 79 glyph_index = FT_Get_Char_Index( 80 face, 81 metrics->root.style_class->standard_char ); 82 if ( glyph_index == 0 ) 83 goto Exit; 84 85 error = FT_Load_Glyph( face, glyph_index, FT_LOAD_NO_SCALE ); 86 if ( error || face->glyph->outline.n_points <= 0 ) 87 goto Exit; 88 89 FT_ZERO( dummy ); 90 91 dummy->units_per_em = metrics->units_per_em; 92 scaler->x_scale = scaler->y_scale = 0x10000L; 93 scaler->x_delta = scaler->y_delta = 0; 94 scaler->face = face; 95 scaler->render_mode = FT_RENDER_MODE_NORMAL; 96 scaler->flags = 0; 97 98 af_glyph_hints_rescale( hints, (AF_StyleMetrics)dummy ); 99 100 error = af_glyph_hints_reload( hints, &face->glyph->outline ); 101 if ( error ) 102 goto Exit; 103 104 for ( dim = 0; dim < AF_DIMENSION_MAX; dim++ ) 105 { 106 AF_LatinAxis axis = &metrics->axis[dim]; 107 AF_AxisHints axhints = &hints->axis[dim]; 108 AF_Segment seg, limit, link; 109 FT_UInt num_widths = 0; 110 111 112 error = af_latin2_hints_compute_segments( hints, 113 (AF_Dimension)dim ); 114 if ( error ) 115 goto Exit; 116 117 af_latin2_hints_link_segments( hints, 118 (AF_Dimension)dim ); 119 120 seg = axhints->segments; 121 limit = seg + axhints->num_segments; 122 123 for ( ; seg < limit; seg++ ) 124 { 125 link = seg->link; 126 127 /* we only consider stem segments there! */ 128 if ( link && link->link == seg && link > seg ) 129 { 130 FT_Pos dist; 131 132 133 dist = seg->pos - link->pos; 134 if ( dist < 0 ) 135 dist = -dist; 136 137 if ( num_widths < AF_LATIN_MAX_WIDTHS ) 138 axis->widths[num_widths++].org = dist; 139 } 140 } 141 142 af_sort_widths( num_widths, axis->widths ); 143 axis->width_count = num_widths; 144 } 145 146 Exit: 147 for ( dim = 0; dim < AF_DIMENSION_MAX; dim++ ) 148 { 149 AF_LatinAxis axis = &metrics->axis[dim]; 150 FT_Pos stdw; 151 152 153 stdw = ( axis->width_count > 0 ) 154 ? axis->widths[0].org 155 : AF_LATIN_CONSTANT( metrics, 50 ); 156 157 /* let's try 20% of the smallest width */ 158 axis->edge_distance_threshold = stdw / 5; 159 axis->standard_width = stdw; 160 axis->extra_light = 0; 161 } 162 } 163 164 af_glyph_hints_done( hints ); 165 } 166 167 168 169 #define AF_LATIN_MAX_TEST_CHARACTERS 12 170 171 172 static const char af_latin2_blue_chars[AF_LATIN_MAX_BLUES] 173 [AF_LATIN_MAX_TEST_CHARACTERS+1] = 174 { 175 "THEZOCQS", 176 "HEZLOCUS", 177 "fijkdbh", 178 "xzroesc", 179 "xzroesc", 180 "pqgjy" 181 }; 182 183 184 static void af_latin2_metrics_init_blues(AF_LatinMetrics metrics,FT_Face face)185 af_latin2_metrics_init_blues( AF_LatinMetrics metrics, 186 FT_Face face ) 187 { 188 FT_Pos flats [AF_LATIN_MAX_TEST_CHARACTERS]; 189 FT_Pos rounds[AF_LATIN_MAX_TEST_CHARACTERS]; 190 FT_Int num_flats; 191 FT_Int num_rounds; 192 FT_Int bb; 193 AF_LatinBlue blue; 194 FT_Error error; 195 AF_LatinAxis axis = &metrics->axis[AF_DIMENSION_VERT]; 196 FT_GlyphSlot glyph = face->glyph; 197 198 199 /* we compute the blues simply by loading each character from the */ 200 /* 'af_latin2_blue_chars[blues]' string, then compute its top-most or */ 201 /* bottom-most points (depending on `AF_IS_TOP_BLUE') */ 202 203 FT_TRACE5(( "blue zones computation\n" 204 "======================\n\n" )); 205 206 for ( bb = 0; bb < AF_LATIN_BLUE_MAX; bb++ ) 207 { 208 const char* p = af_latin2_blue_chars[bb]; 209 const char* limit = p + AF_LATIN_MAX_TEST_CHARACTERS; 210 FT_Pos* blue_ref; 211 FT_Pos* blue_shoot; 212 213 214 FT_TRACE5(( "blue zone %d:\n", bb )); 215 216 num_flats = 0; 217 num_rounds = 0; 218 219 for ( ; p < limit && *p; p++ ) 220 { 221 FT_UInt glyph_index; 222 FT_Int best_point, best_y, best_first, best_last; 223 FT_Vector* points; 224 FT_Bool round; 225 226 227 /* load the character in the face -- skip unknown or empty ones */ 228 glyph_index = FT_Get_Char_Index( face, (FT_UInt)*p ); 229 if ( glyph_index == 0 ) 230 continue; 231 232 error = FT_Load_Glyph( face, glyph_index, FT_LOAD_NO_SCALE ); 233 if ( error || glyph->outline.n_points <= 0 ) 234 continue; 235 236 /* now compute min or max point indices and coordinates */ 237 points = glyph->outline.points; 238 best_point = -1; 239 best_y = 0; /* make compiler happy */ 240 best_first = 0; /* ditto */ 241 best_last = 0; /* ditto */ 242 243 { 244 FT_Int nn; 245 FT_Int first = 0; 246 FT_Int last = -1; 247 248 249 for ( nn = 0; nn < glyph->outline.n_contours; first = last+1, nn++ ) 250 { 251 FT_Int old_best_point = best_point; 252 FT_Int pp; 253 254 255 last = glyph->outline.contours[nn]; 256 257 /* Avoid single-point contours since they are never rasterized. */ 258 /* In some fonts, they correspond to mark attachment points */ 259 /* which are way outside of the glyph's real outline. */ 260 if ( last == first ) 261 continue; 262 263 if ( AF_LATIN_IS_TOP_BLUE( bb ) ) 264 { 265 for ( pp = first; pp <= last; pp++ ) 266 if ( best_point < 0 || points[pp].y > best_y ) 267 { 268 best_point = pp; 269 best_y = points[pp].y; 270 } 271 } 272 else 273 { 274 for ( pp = first; pp <= last; pp++ ) 275 if ( best_point < 0 || points[pp].y < best_y ) 276 { 277 best_point = pp; 278 best_y = points[pp].y; 279 } 280 } 281 282 if ( best_point != old_best_point ) 283 { 284 best_first = first; 285 best_last = last; 286 } 287 } 288 FT_TRACE5(( " %c %d", *p, best_y )); 289 } 290 291 /* now check whether the point belongs to a straight or round */ 292 /* segment; we first need to find in which contour the extremum */ 293 /* lies, then inspect its previous and next points */ 294 { 295 FT_Pos best_x = points[best_point].x; 296 FT_Int start, end, prev, next; 297 FT_Pos dist; 298 299 300 /* now look for the previous and next points that are not on the */ 301 /* same Y coordinate. Threshold the `closeness'... */ 302 start = end = best_point; 303 304 do 305 { 306 prev = start - 1; 307 if ( prev < best_first ) 308 prev = best_last; 309 310 dist = FT_ABS( points[prev].y - best_y ); 311 /* accept a small distance or a small angle (both values are */ 312 /* heuristic; value 20 corresponds to approx. 2.9 degrees) */ 313 if ( dist > 5 ) 314 if ( FT_ABS( points[prev].x - best_x ) <= 20 * dist ) 315 break; 316 317 start = prev; 318 319 } while ( start != best_point ); 320 321 do 322 { 323 next = end + 1; 324 if ( next > best_last ) 325 next = best_first; 326 327 dist = FT_ABS( points[next].y - best_y ); 328 if ( dist > 5 ) 329 if ( FT_ABS( points[next].x - best_x ) <= 20 * dist ) 330 break; 331 332 end = next; 333 334 } while ( end != best_point ); 335 336 /* now, set the `round' flag depending on the segment's kind */ 337 round = FT_BOOL( 338 FT_CURVE_TAG( glyph->outline.tags[start] ) != FT_CURVE_TAG_ON || 339 FT_CURVE_TAG( glyph->outline.tags[ end ] ) != FT_CURVE_TAG_ON ); 340 341 FT_TRACE5(( " (%s)\n", round ? "round" : "flat" )); 342 } 343 344 if ( round ) 345 rounds[num_rounds++] = best_y; 346 else 347 flats[num_flats++] = best_y; 348 } 349 350 if ( num_flats == 0 && num_rounds == 0 ) 351 { 352 /* 353 * we couldn't find a single glyph to compute this blue zone, 354 * we will simply ignore it then 355 */ 356 FT_TRACE5(( " empty\n" )); 357 continue; 358 } 359 360 /* we have computed the contents of the `rounds' and `flats' tables, */ 361 /* now determine the reference and overshoot position of the blue -- */ 362 /* we simply take the median value after a simple sort */ 363 af_sort_pos( num_rounds, rounds ); 364 af_sort_pos( num_flats, flats ); 365 366 blue = & axis->blues[axis->blue_count]; 367 blue_ref = & blue->ref.org; 368 blue_shoot = & blue->shoot.org; 369 370 axis->blue_count++; 371 372 if ( num_flats == 0 ) 373 { 374 *blue_ref = 375 *blue_shoot = rounds[num_rounds / 2]; 376 } 377 else if ( num_rounds == 0 ) 378 { 379 *blue_ref = 380 *blue_shoot = flats[num_flats / 2]; 381 } 382 else 383 { 384 *blue_ref = flats[num_flats / 2]; 385 *blue_shoot = rounds[num_rounds / 2]; 386 } 387 388 /* there are sometimes problems: if the overshoot position of top */ 389 /* zones is under its reference position, or the opposite for bottom */ 390 /* zones. We must thus check everything there and correct the errors */ 391 if ( *blue_shoot != *blue_ref ) 392 { 393 FT_Pos ref = *blue_ref; 394 FT_Pos shoot = *blue_shoot; 395 FT_Bool over_ref = FT_BOOL( shoot > ref ); 396 397 398 if ( AF_LATIN_IS_TOP_BLUE( bb ) ^ over_ref ) 399 { 400 *blue_ref = 401 *blue_shoot = ( shoot + ref ) / 2; 402 403 FT_TRACE5(( " [overshoot smaller than reference," 404 " taking mean value]\n" )); 405 } 406 } 407 408 blue->flags = 0; 409 if ( AF_LATIN_IS_TOP_BLUE( bb ) ) 410 blue->flags |= AF_LATIN_BLUE_TOP; 411 412 /* 413 * The following flag is used later to adjust the y and x scales 414 * in order to optimize the pixel grid alignment of the top of small 415 * letters. 416 */ 417 if ( AF_LATIN_IS_X_HEIGHT_BLUE( bb ) ) 418 blue->flags |= AF_LATIN_BLUE_ADJUSTMENT; 419 420 FT_TRACE5(( " -> reference = %ld\n" 421 " overshoot = %ld\n", 422 *blue_ref, *blue_shoot )); 423 } 424 425 return; 426 } 427 428 429 FT_LOCAL_DEF( void ) af_latin2_metrics_check_digits(AF_LatinMetrics metrics,FT_Face face)430 af_latin2_metrics_check_digits( AF_LatinMetrics metrics, 431 FT_Face face ) 432 { 433 FT_UInt i; 434 FT_Bool started = 0, same_width = 1; 435 FT_Fixed advance, old_advance = 0; 436 437 438 /* check whether all ASCII digits have the same advance width; */ 439 /* digit `0' is 0x30 in all supported charmaps */ 440 for ( i = 0x30; i <= 0x39; i++ ) 441 { 442 FT_UInt glyph_index; 443 444 445 glyph_index = FT_Get_Char_Index( face, i ); 446 if ( glyph_index == 0 ) 447 continue; 448 449 if ( FT_Get_Advance( face, glyph_index, 450 FT_LOAD_NO_SCALE | 451 FT_LOAD_NO_HINTING | 452 FT_LOAD_IGNORE_TRANSFORM, 453 &advance ) ) 454 continue; 455 456 if ( started ) 457 { 458 if ( advance != old_advance ) 459 { 460 same_width = 0; 461 break; 462 } 463 } 464 else 465 { 466 old_advance = advance; 467 started = 1; 468 } 469 } 470 471 metrics->root.digits_have_same_width = same_width; 472 } 473 474 475 FT_LOCAL_DEF( FT_Error ) af_latin2_metrics_init(AF_LatinMetrics metrics,FT_Face face)476 af_latin2_metrics_init( AF_LatinMetrics metrics, 477 FT_Face face ) 478 { 479 FT_Error error = FT_Err_Ok; 480 FT_CharMap oldmap = face->charmap; 481 FT_UInt ee; 482 483 static const FT_Encoding latin_encodings[] = 484 { 485 FT_ENCODING_UNICODE, 486 FT_ENCODING_APPLE_ROMAN, 487 FT_ENCODING_ADOBE_STANDARD, 488 FT_ENCODING_ADOBE_LATIN_1, 489 FT_ENCODING_NONE /* end of list */ 490 }; 491 492 493 metrics->units_per_em = face->units_per_EM; 494 495 /* do we have a latin charmap in there? */ 496 for ( ee = 0; latin_encodings[ee] != FT_ENCODING_NONE; ee++ ) 497 { 498 error = FT_Select_Charmap( face, latin_encodings[ee] ); 499 if ( !error ) 500 break; 501 } 502 503 if ( !error ) 504 { 505 af_latin2_metrics_init_widths( metrics, face ); 506 af_latin2_metrics_init_blues( metrics, face ); 507 af_latin2_metrics_check_digits( metrics, face ); 508 } 509 510 FT_Set_Charmap( face, oldmap ); 511 return FT_Err_Ok; 512 } 513 514 515 static void af_latin2_metrics_scale_dim(AF_LatinMetrics metrics,AF_Scaler scaler,AF_Dimension dim)516 af_latin2_metrics_scale_dim( AF_LatinMetrics metrics, 517 AF_Scaler scaler, 518 AF_Dimension dim ) 519 { 520 FT_Fixed scale; 521 FT_Pos delta; 522 AF_LatinAxis axis; 523 FT_UInt nn; 524 525 526 if ( dim == AF_DIMENSION_HORZ ) 527 { 528 scale = scaler->x_scale; 529 delta = scaler->x_delta; 530 } 531 else 532 { 533 scale = scaler->y_scale; 534 delta = scaler->y_delta; 535 } 536 537 axis = &metrics->axis[dim]; 538 539 if ( axis->org_scale == scale && axis->org_delta == delta ) 540 return; 541 542 axis->org_scale = scale; 543 axis->org_delta = delta; 544 545 /* 546 * correct Y scale to optimize the alignment of the top of small 547 * letters to the pixel grid 548 */ 549 if ( dim == AF_DIMENSION_VERT ) 550 { 551 AF_LatinAxis vaxis = &metrics->axis[AF_DIMENSION_VERT]; 552 AF_LatinBlue blue = NULL; 553 554 555 for ( nn = 0; nn < vaxis->blue_count; nn++ ) 556 { 557 if ( vaxis->blues[nn].flags & AF_LATIN_BLUE_ADJUSTMENT ) 558 { 559 blue = &vaxis->blues[nn]; 560 break; 561 } 562 } 563 564 if ( blue ) 565 { 566 FT_Pos scaled; 567 FT_Pos threshold; 568 FT_Pos fitted; 569 FT_UInt limit; 570 FT_UInt ppem; 571 572 573 scaled = FT_MulFix( blue->shoot.org, scaler->y_scale ); 574 ppem = metrics->root.scaler.face->size->metrics.x_ppem; 575 limit = metrics->root.globals->increase_x_height; 576 threshold = 40; 577 578 /* if the `increase-x-height' property is active, */ 579 /* we round up much more often */ 580 if ( limit && 581 ppem <= limit && 582 ppem >= AF_PROP_INCREASE_X_HEIGHT_MIN ) 583 threshold = 52; 584 585 fitted = ( scaled + threshold ) & ~63; 586 587 #if 1 588 if ( scaled != fitted ) 589 { 590 scale = FT_MulDiv( scale, fitted, scaled ); 591 FT_TRACE5(( "== scaled x-top = %.2g" 592 " fitted = %.2g, scaling = %.4g\n", 593 scaled / 64.0, fitted / 64.0, 594 ( fitted * 1.0 ) / scaled )); 595 } 596 #endif 597 } 598 } 599 600 axis->scale = scale; 601 axis->delta = delta; 602 603 if ( dim == AF_DIMENSION_HORZ ) 604 { 605 metrics->root.scaler.x_scale = scale; 606 metrics->root.scaler.x_delta = delta; 607 } 608 else 609 { 610 metrics->root.scaler.y_scale = scale; 611 metrics->root.scaler.y_delta = delta; 612 } 613 614 /* scale the standard widths */ 615 for ( nn = 0; nn < axis->width_count; nn++ ) 616 { 617 AF_Width width = axis->widths + nn; 618 619 620 width->cur = FT_MulFix( width->org, scale ); 621 width->fit = width->cur; 622 } 623 624 /* an extra-light axis corresponds to a standard width that is */ 625 /* smaller than 5/8 pixels */ 626 axis->extra_light = 627 (FT_Bool)( FT_MulFix( axis->standard_width, scale ) < 32 + 8 ); 628 629 if ( dim == AF_DIMENSION_VERT ) 630 { 631 /* scale the blue zones */ 632 for ( nn = 0; nn < axis->blue_count; nn++ ) 633 { 634 AF_LatinBlue blue = &axis->blues[nn]; 635 FT_Pos dist; 636 637 638 blue->ref.cur = FT_MulFix( blue->ref.org, scale ) + delta; 639 blue->ref.fit = blue->ref.cur; 640 blue->shoot.cur = FT_MulFix( blue->shoot.org, scale ) + delta; 641 blue->shoot.fit = blue->shoot.cur; 642 blue->flags &= ~AF_LATIN_BLUE_ACTIVE; 643 644 /* a blue zone is only active if it is less than 3/4 pixels tall */ 645 dist = FT_MulFix( blue->ref.org - blue->shoot.org, scale ); 646 if ( dist <= 48 && dist >= -48 ) 647 { 648 FT_Pos delta1, delta2; 649 650 delta1 = blue->shoot.org - blue->ref.org; 651 delta2 = delta1; 652 if ( delta1 < 0 ) 653 delta2 = -delta2; 654 655 delta2 = FT_MulFix( delta2, scale ); 656 657 if ( delta2 < 32 ) 658 delta2 = 0; 659 else if ( delta2 < 64 ) 660 delta2 = 32 + ( ( ( delta2 - 32 ) + 16 ) & ~31 ); 661 else 662 delta2 = FT_PIX_ROUND( delta2 ); 663 664 if ( delta1 < 0 ) 665 delta2 = -delta2; 666 667 blue->ref.fit = FT_PIX_ROUND( blue->ref.cur ); 668 blue->shoot.fit = blue->ref.fit + delta2; 669 670 FT_TRACE5(( ">> activating blue zone %d:" 671 " ref.cur=%.2g ref.fit=%.2g" 672 " shoot.cur=%.2g shoot.fit=%.2g\n", 673 nn, blue->ref.cur / 64.0, blue->ref.fit / 64.0, 674 blue->shoot.cur / 64.0, blue->shoot.fit / 64.0 )); 675 676 blue->flags |= AF_LATIN_BLUE_ACTIVE; 677 } 678 } 679 } 680 } 681 682 683 FT_LOCAL_DEF( void ) af_latin2_metrics_scale(AF_LatinMetrics metrics,AF_Scaler scaler)684 af_latin2_metrics_scale( AF_LatinMetrics metrics, 685 AF_Scaler scaler ) 686 { 687 metrics->root.scaler.render_mode = scaler->render_mode; 688 metrics->root.scaler.face = scaler->face; 689 metrics->root.scaler.flags = scaler->flags; 690 691 af_latin2_metrics_scale_dim( metrics, scaler, AF_DIMENSION_HORZ ); 692 af_latin2_metrics_scale_dim( metrics, scaler, AF_DIMENSION_VERT ); 693 } 694 695 696 /*************************************************************************/ 697 /*************************************************************************/ 698 /***** *****/ 699 /***** L A T I N G L Y P H A N A L Y S I S *****/ 700 /***** *****/ 701 /*************************************************************************/ 702 /*************************************************************************/ 703 704 #define SORT_SEGMENTS 705 706 FT_LOCAL_DEF( FT_Error ) af_latin2_hints_compute_segments(AF_GlyphHints hints,AF_Dimension dim)707 af_latin2_hints_compute_segments( AF_GlyphHints hints, 708 AF_Dimension dim ) 709 { 710 AF_AxisHints axis = &hints->axis[dim]; 711 FT_Memory memory = hints->memory; 712 FT_Error error = FT_Err_Ok; 713 AF_Segment segment = NULL; 714 AF_SegmentRec seg0; 715 AF_Point* contour = hints->contours; 716 AF_Point* contour_limit = contour + hints->num_contours; 717 AF_Direction major_dir, segment_dir; 718 719 720 FT_ZERO( &seg0 ); 721 seg0.score = 32000; 722 seg0.flags = AF_EDGE_NORMAL; 723 724 major_dir = (AF_Direction)FT_ABS( axis->major_dir ); 725 segment_dir = major_dir; 726 727 axis->num_segments = 0; 728 729 /* set up (u,v) in each point */ 730 if ( dim == AF_DIMENSION_HORZ ) 731 { 732 AF_Point point = hints->points; 733 AF_Point limit = point + hints->num_points; 734 735 736 for ( ; point < limit; point++ ) 737 { 738 point->u = point->fx; 739 point->v = point->fy; 740 } 741 } 742 else 743 { 744 AF_Point point = hints->points; 745 AF_Point limit = point + hints->num_points; 746 747 748 for ( ; point < limit; point++ ) 749 { 750 point->u = point->fy; 751 point->v = point->fx; 752 } 753 } 754 755 /* do each contour separately */ 756 for ( ; contour < contour_limit; contour++ ) 757 { 758 AF_Point point = contour[0]; 759 AF_Point start = point; 760 AF_Point last = point->prev; 761 762 763 if ( point == last ) /* skip singletons -- just in case */ 764 continue; 765 766 /* already on an edge ?, backtrack to find its start */ 767 if ( FT_ABS( point->in_dir ) == major_dir ) 768 { 769 point = point->prev; 770 771 while ( point->in_dir == start->in_dir ) 772 point = point->prev; 773 } 774 else /* otherwise, find first segment start, if any */ 775 { 776 while ( FT_ABS( point->out_dir ) != major_dir ) 777 { 778 point = point->next; 779 780 if ( point == start ) 781 goto NextContour; 782 } 783 } 784 785 start = point; 786 787 for (;;) 788 { 789 AF_Point first; 790 FT_Pos min_u, min_v, max_u, max_v; 791 792 /* we're at the start of a new segment */ 793 FT_ASSERT( FT_ABS( point->out_dir ) == major_dir && 794 point->in_dir != point->out_dir ); 795 first = point; 796 797 min_u = max_u = point->u; 798 min_v = max_v = point->v; 799 800 point = point->next; 801 802 while ( point->out_dir == first->out_dir ) 803 { 804 point = point->next; 805 806 if ( point->u < min_u ) 807 min_u = point->u; 808 809 if ( point->u > max_u ) 810 max_u = point->u; 811 } 812 813 if ( point->v < min_v ) 814 min_v = point->v; 815 816 if ( point->v > max_v ) 817 max_v = point->v; 818 819 /* record new segment */ 820 error = af_axis_hints_new_segment( axis, memory, &segment ); 821 if ( error ) 822 goto Exit; 823 824 segment[0] = seg0; 825 segment->dir = first->out_dir; 826 segment->first = first; 827 segment->last = point; 828 segment->pos = (FT_Short)( ( min_u + max_u ) >> 1 ); 829 segment->min_coord = (FT_Short) min_v; 830 segment->max_coord = (FT_Short) max_v; 831 segment->height = (FT_Short)( max_v - min_v ); 832 833 /* a segment is round if it doesn't have successive */ 834 /* on-curve points. */ 835 { 836 AF_Point pt = first; 837 AF_Point last = point; 838 AF_Flags f0 = (AF_Flags)( pt->flags & AF_FLAG_CONTROL ); 839 AF_Flags f1; 840 841 842 segment->flags &= ~AF_EDGE_ROUND; 843 844 for ( ; pt != last; f0 = f1 ) 845 { 846 pt = pt->next; 847 f1 = (AF_Flags)( pt->flags & AF_FLAG_CONTROL ); 848 849 if ( !f0 && !f1 ) 850 break; 851 852 if ( pt == last ) 853 segment->flags |= AF_EDGE_ROUND; 854 } 855 } 856 857 /* this can happen in the case of a degenerate contour 858 * e.g. a 2-point vertical contour 859 */ 860 if ( point == start ) 861 break; 862 863 /* jump to the start of the next segment, if any */ 864 while ( FT_ABS( point->out_dir ) != major_dir ) 865 { 866 point = point->next; 867 868 if ( point == start ) 869 goto NextContour; 870 } 871 } 872 873 NextContour: 874 ; 875 } /* contours */ 876 877 /* now slightly increase the height of segments when this makes */ 878 /* sense -- this is used to better detect and ignore serifs */ 879 { 880 AF_Segment segments = axis->segments; 881 AF_Segment segments_end = segments + axis->num_segments; 882 883 884 for ( segment = segments; segment < segments_end; segment++ ) 885 { 886 AF_Point first = segment->first; 887 AF_Point last = segment->last; 888 AF_Point p; 889 FT_Pos first_v = first->v; 890 FT_Pos last_v = last->v; 891 892 893 if ( first_v < last_v ) 894 { 895 p = first->prev; 896 if ( p->v < first_v ) 897 segment->height = (FT_Short)( segment->height + 898 ( ( first_v - p->v ) >> 1 ) ); 899 900 p = last->next; 901 if ( p->v > last_v ) 902 segment->height = (FT_Short)( segment->height + 903 ( ( p->v - last_v ) >> 1 ) ); 904 } 905 else 906 { 907 p = first->prev; 908 if ( p->v > first_v ) 909 segment->height = (FT_Short)( segment->height + 910 ( ( p->v - first_v ) >> 1 ) ); 911 912 p = last->next; 913 if ( p->v < last_v ) 914 segment->height = (FT_Short)( segment->height + 915 ( ( last_v - p->v ) >> 1 ) ); 916 } 917 } 918 } 919 920 #ifdef AF_SORT_SEGMENTS 921 /* place all segments with a negative direction to the start 922 * of the array, used to speed up segment linking later... 923 */ 924 { 925 AF_Segment segments = axis->segments; 926 FT_UInt count = axis->num_segments; 927 FT_UInt ii, jj; 928 929 for ( ii = 0; ii < count; ii++ ) 930 { 931 if ( segments[ii].dir > 0 ) 932 { 933 for ( jj = ii + 1; jj < count; jj++ ) 934 { 935 if ( segments[jj].dir < 0 ) 936 { 937 AF_SegmentRec tmp; 938 939 940 tmp = segments[ii]; 941 segments[ii] = segments[jj]; 942 segments[jj] = tmp; 943 944 break; 945 } 946 } 947 948 if ( jj == count ) 949 break; 950 } 951 } 952 axis->mid_segments = ii; 953 } 954 #endif 955 956 Exit: 957 return error; 958 } 959 960 961 FT_LOCAL_DEF( void ) af_latin2_hints_link_segments(AF_GlyphHints hints,AF_Dimension dim)962 af_latin2_hints_link_segments( AF_GlyphHints hints, 963 AF_Dimension dim ) 964 { 965 AF_AxisHints axis = &hints->axis[dim]; 966 AF_Segment segments = axis->segments; 967 AF_Segment segment_limit = segments + axis->num_segments; 968 #ifdef AF_SORT_SEGMENTS 969 AF_Segment segment_mid = segments + axis->mid_segments; 970 #endif 971 FT_Pos len_threshold, len_score; 972 AF_Segment seg1, seg2; 973 974 975 len_threshold = AF_LATIN_CONSTANT( hints->metrics, 8 ); 976 if ( len_threshold == 0 ) 977 len_threshold = 1; 978 979 len_score = AF_LATIN_CONSTANT( hints->metrics, 6000 ); 980 981 #ifdef AF_SORT_SEGMENTS 982 for ( seg1 = segments; seg1 < segment_mid; seg1++ ) 983 { 984 if ( seg1->dir != axis->major_dir ) 985 continue; 986 987 for ( seg2 = segment_mid; seg2 < segment_limit; seg2++ ) 988 #else 989 /* now compare each segment to the others */ 990 for ( seg1 = segments; seg1 < segment_limit; seg1++ ) 991 { 992 if ( seg1->dir != axis->major_dir ) 993 continue; 994 995 for ( seg2 = segments; seg2 < segment_limit; seg2++ ) 996 if ( seg1->dir + seg2->dir == 0 && seg2->pos > seg1->pos ) 997 #endif 998 { 999 FT_Pos pos1 = seg1->pos; 1000 FT_Pos pos2 = seg2->pos; 1001 FT_Pos dist = pos2 - pos1; 1002 1003 1004 if ( dist < 0 ) 1005 continue; 1006 1007 { 1008 FT_Pos min = seg1->min_coord; 1009 FT_Pos max = seg1->max_coord; 1010 FT_Pos len, score; 1011 1012 1013 if ( min < seg2->min_coord ) 1014 min = seg2->min_coord; 1015 1016 if ( max > seg2->max_coord ) 1017 max = seg2->max_coord; 1018 1019 len = max - min; 1020 if ( len >= len_threshold ) 1021 { 1022 score = dist + len_score / len; 1023 if ( score < seg1->score ) 1024 { 1025 seg1->score = score; 1026 seg1->link = seg2; 1027 } 1028 1029 if ( score < seg2->score ) 1030 { 1031 seg2->score = score; 1032 seg2->link = seg1; 1033 } 1034 } 1035 } 1036 } 1037 } 1038 #if 0 1039 } 1040 #endif 1041 1042 /* now, compute the `serif' segments */ 1043 for ( seg1 = segments; seg1 < segment_limit; seg1++ ) 1044 { 1045 seg2 = seg1->link; 1046 1047 if ( seg2 ) 1048 { 1049 if ( seg2->link != seg1 ) 1050 { 1051 seg1->link = 0; 1052 seg1->serif = seg2->link; 1053 } 1054 } 1055 } 1056 } 1057 1058 1059 FT_LOCAL_DEF( FT_Error ) af_latin2_hints_compute_edges(AF_GlyphHints hints,AF_Dimension dim)1060 af_latin2_hints_compute_edges( AF_GlyphHints hints, 1061 AF_Dimension dim ) 1062 { 1063 AF_AxisHints axis = &hints->axis[dim]; 1064 FT_Error error = FT_Err_Ok; 1065 FT_Memory memory = hints->memory; 1066 AF_LatinAxis laxis = &((AF_LatinMetrics)hints->metrics)->axis[dim]; 1067 1068 AF_Segment segments = axis->segments; 1069 AF_Segment segment_limit = segments + axis->num_segments; 1070 AF_Segment seg; 1071 1072 AF_Direction up_dir; 1073 FT_Fixed scale; 1074 FT_Pos edge_distance_threshold; 1075 FT_Pos segment_length_threshold; 1076 1077 1078 axis->num_edges = 0; 1079 1080 scale = ( dim == AF_DIMENSION_HORZ ) ? hints->x_scale 1081 : hints->y_scale; 1082 1083 up_dir = ( dim == AF_DIMENSION_HORZ ) ? AF_DIR_UP 1084 : AF_DIR_RIGHT; 1085 1086 /* 1087 * We want to ignore very small (mostly serif) segments, we do that 1088 * by ignoring those that whose length is less than a given fraction 1089 * of the standard width. If there is no standard width, we ignore 1090 * those that are less than a given size in pixels 1091 * 1092 * also, unlink serif segments that are linked to segments farther 1093 * than 50% of the standard width 1094 */ 1095 if ( dim == AF_DIMENSION_HORZ ) 1096 { 1097 if ( laxis->width_count > 0 ) 1098 segment_length_threshold = ( laxis->standard_width * 10 ) >> 4; 1099 else 1100 segment_length_threshold = FT_DivFix( 64, hints->y_scale ); 1101 } 1102 else 1103 segment_length_threshold = 0; 1104 1105 /*********************************************************************/ 1106 /* */ 1107 /* We will begin by generating a sorted table of edges for the */ 1108 /* current direction. To do so, we simply scan each segment and try */ 1109 /* to find an edge in our table that corresponds to its position. */ 1110 /* */ 1111 /* If no edge is found, we create and insert a new edge in the */ 1112 /* sorted table. Otherwise, we simply add the segment to the edge's */ 1113 /* list which will be processed in the second step to compute the */ 1114 /* edge's properties. */ 1115 /* */ 1116 /* Note that the edges table is sorted along the segment/edge */ 1117 /* position. */ 1118 /* */ 1119 /*********************************************************************/ 1120 1121 edge_distance_threshold = FT_MulFix( laxis->edge_distance_threshold, 1122 scale ); 1123 if ( edge_distance_threshold > 64 / 4 ) 1124 edge_distance_threshold = 64 / 4; 1125 1126 edge_distance_threshold = FT_DivFix( edge_distance_threshold, 1127 scale ); 1128 1129 for ( seg = segments; seg < segment_limit; seg++ ) 1130 { 1131 AF_Edge found = 0; 1132 FT_Int ee; 1133 1134 1135 if ( seg->height < segment_length_threshold ) 1136 continue; 1137 1138 /* A special case for serif edges: If they are smaller than */ 1139 /* 1.5 pixels we ignore them. */ 1140 if ( seg->serif ) 1141 { 1142 FT_Pos dist = seg->serif->pos - seg->pos; 1143 1144 1145 if ( dist < 0 ) 1146 dist = -dist; 1147 1148 if ( dist >= laxis->standard_width >> 1 ) 1149 { 1150 /* unlink this serif, it is too distant from its reference stem */ 1151 seg->serif = NULL; 1152 } 1153 else if ( 2*seg->height < 3 * segment_length_threshold ) 1154 continue; 1155 } 1156 1157 /* look for an edge corresponding to the segment */ 1158 for ( ee = 0; ee < axis->num_edges; ee++ ) 1159 { 1160 AF_Edge edge = axis->edges + ee; 1161 FT_Pos dist; 1162 1163 1164 dist = seg->pos - edge->fpos; 1165 if ( dist < 0 ) 1166 dist = -dist; 1167 1168 if ( dist < edge_distance_threshold && edge->dir == seg->dir ) 1169 { 1170 found = edge; 1171 break; 1172 } 1173 } 1174 1175 if ( !found ) 1176 { 1177 AF_Edge edge; 1178 1179 1180 /* insert a new edge in the list and */ 1181 /* sort according to the position */ 1182 error = af_axis_hints_new_edge( axis, seg->pos, seg->dir, 1183 memory, &edge ); 1184 if ( error ) 1185 goto Exit; 1186 1187 /* add the segment to the new edge's list */ 1188 FT_ZERO( edge ); 1189 1190 edge->first = seg; 1191 edge->last = seg; 1192 edge->dir = seg->dir; 1193 edge->fpos = seg->pos; 1194 edge->opos = FT_MulFix( seg->pos, scale ); 1195 edge->pos = edge->opos; 1196 seg->edge_next = seg; 1197 } 1198 else 1199 { 1200 /* if an edge was found, simply add the segment to the edge's */ 1201 /* list */ 1202 seg->edge_next = found->first; 1203 found->last->edge_next = seg; 1204 found->last = seg; 1205 } 1206 } 1207 1208 1209 /*********************************************************************/ 1210 /* */ 1211 /* Good, we will now compute each edge's properties according to */ 1212 /* segments found on its position. Basically, these are: */ 1213 /* */ 1214 /* - edge's main direction */ 1215 /* - stem edge, serif edge or both (which defaults to stem then) */ 1216 /* - rounded edge, straight or both (which defaults to straight) */ 1217 /* - link for edge */ 1218 /* */ 1219 /*********************************************************************/ 1220 1221 /* first of all, set the `edge' field in each segment -- this is */ 1222 /* required in order to compute edge links */ 1223 1224 /* 1225 * Note that removing this loop and setting the `edge' field of each 1226 * segment directly in the code above slows down execution speed for 1227 * some reasons on platforms like the Sun. 1228 */ 1229 { 1230 AF_Edge edges = axis->edges; 1231 AF_Edge edge_limit = edges + axis->num_edges; 1232 AF_Edge edge; 1233 1234 1235 for ( edge = edges; edge < edge_limit; edge++ ) 1236 { 1237 seg = edge->first; 1238 if ( seg ) 1239 do 1240 { 1241 seg->edge = edge; 1242 seg = seg->edge_next; 1243 1244 } while ( seg != edge->first ); 1245 } 1246 1247 /* now, compute each edge properties */ 1248 for ( edge = edges; edge < edge_limit; edge++ ) 1249 { 1250 FT_Int is_round = 0; /* does it contain round segments? */ 1251 FT_Int is_straight = 0; /* does it contain straight segments? */ 1252 #if 0 1253 FT_Pos ups = 0; /* number of upwards segments */ 1254 FT_Pos downs = 0; /* number of downwards segments */ 1255 #endif 1256 1257 1258 seg = edge->first; 1259 1260 do 1261 { 1262 FT_Bool is_serif; 1263 1264 1265 /* check for roundness of segment */ 1266 if ( seg->flags & AF_EDGE_ROUND ) 1267 is_round++; 1268 else 1269 is_straight++; 1270 1271 #if 0 1272 /* check for segment direction */ 1273 if ( seg->dir == up_dir ) 1274 ups += seg->max_coord-seg->min_coord; 1275 else 1276 downs += seg->max_coord-seg->min_coord; 1277 #endif 1278 1279 /* check for links -- if seg->serif is set, then seg->link must */ 1280 /* be ignored */ 1281 is_serif = (FT_Bool)( seg->serif && 1282 seg->serif->edge && 1283 seg->serif->edge != edge ); 1284 1285 if ( ( seg->link && seg->link->edge != NULL ) || is_serif ) 1286 { 1287 AF_Edge edge2; 1288 AF_Segment seg2; 1289 1290 1291 edge2 = edge->link; 1292 seg2 = seg->link; 1293 1294 if ( is_serif ) 1295 { 1296 seg2 = seg->serif; 1297 edge2 = edge->serif; 1298 } 1299 1300 if ( edge2 ) 1301 { 1302 FT_Pos edge_delta; 1303 FT_Pos seg_delta; 1304 1305 1306 edge_delta = edge->fpos - edge2->fpos; 1307 if ( edge_delta < 0 ) 1308 edge_delta = -edge_delta; 1309 1310 seg_delta = seg->pos - seg2->pos; 1311 if ( seg_delta < 0 ) 1312 seg_delta = -seg_delta; 1313 1314 if ( seg_delta < edge_delta ) 1315 edge2 = seg2->edge; 1316 } 1317 else 1318 edge2 = seg2->edge; 1319 1320 if ( is_serif ) 1321 { 1322 edge->serif = edge2; 1323 edge2->flags |= AF_EDGE_SERIF; 1324 } 1325 else 1326 edge->link = edge2; 1327 } 1328 1329 seg = seg->edge_next; 1330 1331 } while ( seg != edge->first ); 1332 1333 /* set the round/straight flags */ 1334 edge->flags = AF_EDGE_NORMAL; 1335 1336 if ( is_round > 0 && is_round >= is_straight ) 1337 edge->flags |= AF_EDGE_ROUND; 1338 1339 #if 0 1340 /* set the edge's main direction */ 1341 edge->dir = AF_DIR_NONE; 1342 1343 if ( ups > downs ) 1344 edge->dir = (FT_Char)up_dir; 1345 1346 else if ( ups < downs ) 1347 edge->dir = (FT_Char)-up_dir; 1348 1349 else if ( ups == downs ) 1350 edge->dir = 0; /* both up and down! */ 1351 #endif 1352 1353 /* gets rid of serifs if link is set */ 1354 /* XXX: This gets rid of many unpleasant artefacts! */ 1355 /* Example: the `c' in cour.pfa at size 13 */ 1356 1357 if ( edge->serif && edge->link ) 1358 edge->serif = 0; 1359 } 1360 } 1361 1362 Exit: 1363 return error; 1364 } 1365 1366 1367 FT_LOCAL_DEF( FT_Error ) af_latin2_hints_detect_features(AF_GlyphHints hints,AF_Dimension dim)1368 af_latin2_hints_detect_features( AF_GlyphHints hints, 1369 AF_Dimension dim ) 1370 { 1371 FT_Error error; 1372 1373 1374 error = af_latin2_hints_compute_segments( hints, dim ); 1375 if ( !error ) 1376 { 1377 af_latin2_hints_link_segments( hints, dim ); 1378 1379 error = af_latin2_hints_compute_edges( hints, dim ); 1380 } 1381 return error; 1382 } 1383 1384 1385 FT_LOCAL_DEF( void ) af_latin2_hints_compute_blue_edges(AF_GlyphHints hints,AF_LatinMetrics metrics)1386 af_latin2_hints_compute_blue_edges( AF_GlyphHints hints, 1387 AF_LatinMetrics metrics ) 1388 { 1389 AF_AxisHints axis = &hints->axis[AF_DIMENSION_VERT]; 1390 AF_Edge edge = axis->edges; 1391 AF_Edge edge_limit = edge + axis->num_edges; 1392 AF_LatinAxis latin = &metrics->axis[AF_DIMENSION_VERT]; 1393 FT_Fixed scale = latin->scale; 1394 FT_Pos best_dist0; /* initial threshold */ 1395 1396 1397 /* compute the initial threshold as a fraction of the EM size */ 1398 best_dist0 = FT_MulFix( metrics->units_per_em / 40, scale ); 1399 1400 if ( best_dist0 > 64 / 2 ) 1401 best_dist0 = 64 / 2; 1402 1403 /* compute which blue zones are active, i.e. have their scaled */ 1404 /* size < 3/4 pixels */ 1405 1406 /* for each horizontal edge search the blue zone which is closest */ 1407 for ( ; edge < edge_limit; edge++ ) 1408 { 1409 FT_Int bb; 1410 AF_Width best_blue = NULL; 1411 FT_Pos best_dist = best_dist0; 1412 1413 for ( bb = 0; bb < AF_LATIN_BLUE_MAX; bb++ ) 1414 { 1415 AF_LatinBlue blue = latin->blues + bb; 1416 FT_Bool is_top_blue, is_major_dir; 1417 1418 1419 /* skip inactive blue zones (i.e., those that are too small) */ 1420 if ( !( blue->flags & AF_LATIN_BLUE_ACTIVE ) ) 1421 continue; 1422 1423 /* if it is a top zone, check for right edges -- if it is a bottom */ 1424 /* zone, check for left edges */ 1425 /* */ 1426 /* of course, that's for TrueType */ 1427 is_top_blue = (FT_Byte)( ( blue->flags & AF_LATIN_BLUE_TOP ) != 0 ); 1428 is_major_dir = FT_BOOL( edge->dir == axis->major_dir ); 1429 1430 /* if it is a top zone, the edge must be against the major */ 1431 /* direction; if it is a bottom zone, it must be in the major */ 1432 /* direction */ 1433 if ( is_top_blue ^ is_major_dir ) 1434 { 1435 FT_Pos dist; 1436 AF_Width compare; 1437 1438 1439 /* if it's a rounded edge, compare it to the overshoot position */ 1440 /* if it's a flat edge, compare it to the reference position */ 1441 if ( edge->flags & AF_EDGE_ROUND ) 1442 compare = &blue->shoot; 1443 else 1444 compare = &blue->ref; 1445 1446 dist = edge->fpos - compare->org; 1447 if ( dist < 0 ) 1448 dist = -dist; 1449 1450 dist = FT_MulFix( dist, scale ); 1451 if ( dist < best_dist ) 1452 { 1453 best_dist = dist; 1454 best_blue = compare; 1455 } 1456 1457 #if 0 1458 /* now, compare it to the overshoot position if the edge is */ 1459 /* rounded, and if the edge is over the reference position of a */ 1460 /* top zone, or under the reference position of a bottom zone */ 1461 if ( edge->flags & AF_EDGE_ROUND && dist != 0 ) 1462 { 1463 FT_Bool is_under_ref = FT_BOOL( edge->fpos < blue->ref.org ); 1464 1465 1466 if ( is_top_blue ^ is_under_ref ) 1467 { 1468 blue = latin->blues + bb; 1469 dist = edge->fpos - blue->shoot.org; 1470 if ( dist < 0 ) 1471 dist = -dist; 1472 1473 dist = FT_MulFix( dist, scale ); 1474 if ( dist < best_dist ) 1475 { 1476 best_dist = dist; 1477 best_blue = & blue->shoot; 1478 } 1479 } 1480 } 1481 #endif 1482 } 1483 } 1484 1485 if ( best_blue ) 1486 edge->blue_edge = best_blue; 1487 } 1488 } 1489 1490 1491 static FT_Error af_latin2_hints_init(AF_GlyphHints hints,AF_LatinMetrics metrics)1492 af_latin2_hints_init( AF_GlyphHints hints, 1493 AF_LatinMetrics metrics ) 1494 { 1495 FT_Render_Mode mode; 1496 FT_UInt32 scaler_flags, other_flags; 1497 FT_Face face = metrics->root.scaler.face; 1498 1499 1500 af_glyph_hints_rescale( hints, (AF_StyleMetrics)metrics ); 1501 1502 /* 1503 * correct x_scale and y_scale if needed, since they may have 1504 * been modified `af_latin2_metrics_scale_dim' above 1505 */ 1506 hints->x_scale = metrics->axis[AF_DIMENSION_HORZ].scale; 1507 hints->x_delta = metrics->axis[AF_DIMENSION_HORZ].delta; 1508 hints->y_scale = metrics->axis[AF_DIMENSION_VERT].scale; 1509 hints->y_delta = metrics->axis[AF_DIMENSION_VERT].delta; 1510 1511 /* compute flags depending on render mode, etc. */ 1512 mode = metrics->root.scaler.render_mode; 1513 1514 #if 0 /* #ifdef AF_CONFIG_OPTION_USE_WARPER */ 1515 if ( mode == FT_RENDER_MODE_LCD || mode == FT_RENDER_MODE_LCD_V ) 1516 { 1517 metrics->root.scaler.render_mode = mode = FT_RENDER_MODE_NORMAL; 1518 } 1519 #endif 1520 1521 scaler_flags = hints->scaler_flags; 1522 other_flags = 0; 1523 1524 /* 1525 * We snap the width of vertical stems for the monochrome and 1526 * horizontal LCD rendering targets only. 1527 */ 1528 if ( mode == FT_RENDER_MODE_MONO || mode == FT_RENDER_MODE_LCD ) 1529 other_flags |= AF_LATIN_HINTS_HORZ_SNAP; 1530 1531 /* 1532 * We snap the width of horizontal stems for the monochrome and 1533 * vertical LCD rendering targets only. 1534 */ 1535 if ( mode == FT_RENDER_MODE_MONO || mode == FT_RENDER_MODE_LCD_V ) 1536 other_flags |= AF_LATIN_HINTS_VERT_SNAP; 1537 1538 /* 1539 * We adjust stems to full pixels only if we don't use the `light' mode. 1540 */ 1541 if ( mode != FT_RENDER_MODE_LIGHT ) 1542 other_flags |= AF_LATIN_HINTS_STEM_ADJUST; 1543 1544 if ( mode == FT_RENDER_MODE_MONO ) 1545 other_flags |= AF_LATIN_HINTS_MONO; 1546 1547 /* 1548 * In `light' hinting mode we disable horizontal hinting completely. 1549 * We also do it if the face is italic. 1550 */ 1551 if ( mode == FT_RENDER_MODE_LIGHT || 1552 ( face->style_flags & FT_STYLE_FLAG_ITALIC ) != 0 ) 1553 scaler_flags |= AF_SCALER_FLAG_NO_HORIZONTAL; 1554 1555 hints->scaler_flags = scaler_flags; 1556 hints->other_flags = other_flags; 1557 1558 return 0; 1559 } 1560 1561 1562 /*************************************************************************/ 1563 /*************************************************************************/ 1564 /***** *****/ 1565 /***** L A T I N G L Y P H G R I D - F I T T I N G *****/ 1566 /***** *****/ 1567 /*************************************************************************/ 1568 /*************************************************************************/ 1569 1570 /* snap a given width in scaled coordinates to one of the */ 1571 /* current standard widths */ 1572 1573 static FT_Pos af_latin2_snap_width(AF_Width widths,FT_Int count,FT_Pos width)1574 af_latin2_snap_width( AF_Width widths, 1575 FT_Int count, 1576 FT_Pos width ) 1577 { 1578 int n; 1579 FT_Pos best = 64 + 32 + 2; 1580 FT_Pos reference = width; 1581 FT_Pos scaled; 1582 1583 1584 for ( n = 0; n < count; n++ ) 1585 { 1586 FT_Pos w; 1587 FT_Pos dist; 1588 1589 1590 w = widths[n].cur; 1591 dist = width - w; 1592 if ( dist < 0 ) 1593 dist = -dist; 1594 if ( dist < best ) 1595 { 1596 best = dist; 1597 reference = w; 1598 } 1599 } 1600 1601 scaled = FT_PIX_ROUND( reference ); 1602 1603 if ( width >= reference ) 1604 { 1605 if ( width < scaled + 48 ) 1606 width = reference; 1607 } 1608 else 1609 { 1610 if ( width > scaled - 48 ) 1611 width = reference; 1612 } 1613 1614 return width; 1615 } 1616 1617 1618 /* compute the snapped width of a given stem */ 1619 1620 static FT_Pos af_latin2_compute_stem_width(AF_GlyphHints hints,AF_Dimension dim,FT_Pos width,AF_Edge_Flags base_flags,AF_Edge_Flags stem_flags)1621 af_latin2_compute_stem_width( AF_GlyphHints hints, 1622 AF_Dimension dim, 1623 FT_Pos width, 1624 AF_Edge_Flags base_flags, 1625 AF_Edge_Flags stem_flags ) 1626 { 1627 AF_LatinMetrics metrics = (AF_LatinMetrics) hints->metrics; 1628 AF_LatinAxis axis = & metrics->axis[dim]; 1629 FT_Pos dist = width; 1630 FT_Int sign = 0; 1631 FT_Int vertical = ( dim == AF_DIMENSION_VERT ); 1632 1633 FT_UNUSED( base_flags ); 1634 1635 1636 if ( !AF_LATIN_HINTS_DO_STEM_ADJUST( hints ) || 1637 axis->extra_light ) 1638 return width; 1639 1640 if ( dist < 0 ) 1641 { 1642 dist = -width; 1643 sign = 1; 1644 } 1645 1646 if ( ( vertical && !AF_LATIN_HINTS_DO_VERT_SNAP( hints ) ) || 1647 ( !vertical && !AF_LATIN_HINTS_DO_HORZ_SNAP( hints ) ) ) 1648 { 1649 /* smooth hinting process: very lightly quantize the stem width */ 1650 1651 /* leave the widths of serifs alone */ 1652 1653 if ( ( stem_flags & AF_EDGE_SERIF ) && vertical && ( dist < 3 * 64 ) ) 1654 goto Done_Width; 1655 1656 #if 0 1657 else if ( ( base_flags & AF_EDGE_ROUND ) ) 1658 { 1659 if ( dist < 80 ) 1660 dist = 64; 1661 } 1662 else if ( dist < 56 ) 1663 dist = 56; 1664 #endif 1665 if ( axis->width_count > 0 ) 1666 { 1667 FT_Pos delta; 1668 1669 1670 /* compare to standard width */ 1671 if ( axis->width_count > 0 ) 1672 { 1673 delta = dist - axis->widths[0].cur; 1674 1675 if ( delta < 0 ) 1676 delta = -delta; 1677 1678 if ( delta < 40 ) 1679 { 1680 dist = axis->widths[0].cur; 1681 if ( dist < 48 ) 1682 dist = 48; 1683 1684 goto Done_Width; 1685 } 1686 } 1687 1688 if ( dist < 3 * 64 ) 1689 { 1690 delta = dist & 63; 1691 dist &= -64; 1692 1693 if ( delta < 10 ) 1694 dist += delta; 1695 1696 else if ( delta < 32 ) 1697 dist += 10; 1698 1699 else if ( delta < 54 ) 1700 dist += 54; 1701 1702 else 1703 dist += delta; 1704 } 1705 else 1706 dist = ( dist + 32 ) & ~63; 1707 } 1708 } 1709 else 1710 { 1711 /* strong hinting process: snap the stem width to integer pixels */ 1712 FT_Pos org_dist = dist; 1713 1714 1715 dist = af_latin2_snap_width( axis->widths, axis->width_count, dist ); 1716 1717 if ( vertical ) 1718 { 1719 /* in the case of vertical hinting, always round */ 1720 /* the stem heights to integer pixels */ 1721 1722 if ( dist >= 64 ) 1723 dist = ( dist + 16 ) & ~63; 1724 else 1725 dist = 64; 1726 } 1727 else 1728 { 1729 if ( AF_LATIN_HINTS_DO_MONO( hints ) ) 1730 { 1731 /* monochrome horizontal hinting: snap widths to integer pixels */ 1732 /* with a different threshold */ 1733 1734 if ( dist < 64 ) 1735 dist = 64; 1736 else 1737 dist = ( dist + 32 ) & ~63; 1738 } 1739 else 1740 { 1741 /* for horizontal anti-aliased hinting, we adopt a more subtle */ 1742 /* approach: we strengthen small stems, round stems whose size */ 1743 /* is between 1 and 2 pixels to an integer, otherwise nothing */ 1744 1745 if ( dist < 48 ) 1746 dist = ( dist + 64 ) >> 1; 1747 1748 else if ( dist < 128 ) 1749 { 1750 /* We only round to an integer width if the corresponding */ 1751 /* distortion is less than 1/4 pixel. Otherwise this */ 1752 /* makes everything worse since the diagonals, which are */ 1753 /* not hinted, appear a lot bolder or thinner than the */ 1754 /* vertical stems. */ 1755 1756 FT_Int delta; 1757 1758 1759 dist = ( dist + 22 ) & ~63; 1760 delta = dist - org_dist; 1761 if ( delta < 0 ) 1762 delta = -delta; 1763 1764 if ( delta >= 16 ) 1765 { 1766 dist = org_dist; 1767 if ( dist < 48 ) 1768 dist = ( dist + 64 ) >> 1; 1769 } 1770 } 1771 else 1772 /* round otherwise to prevent color fringes in LCD mode */ 1773 dist = ( dist + 32 ) & ~63; 1774 } 1775 } 1776 } 1777 1778 Done_Width: 1779 if ( sign ) 1780 dist = -dist; 1781 1782 return dist; 1783 } 1784 1785 1786 /* align one stem edge relative to the previous stem edge */ 1787 1788 static void af_latin2_align_linked_edge(AF_GlyphHints hints,AF_Dimension dim,AF_Edge base_edge,AF_Edge stem_edge)1789 af_latin2_align_linked_edge( AF_GlyphHints hints, 1790 AF_Dimension dim, 1791 AF_Edge base_edge, 1792 AF_Edge stem_edge ) 1793 { 1794 FT_Pos dist = stem_edge->opos - base_edge->opos; 1795 1796 FT_Pos fitted_width = af_latin2_compute_stem_width( 1797 hints, dim, dist, 1798 (AF_Edge_Flags)base_edge->flags, 1799 (AF_Edge_Flags)stem_edge->flags ); 1800 1801 1802 stem_edge->pos = base_edge->pos + fitted_width; 1803 1804 FT_TRACE5(( "LINK: edge %d (opos=%.2f) linked to (%.2f), " 1805 "dist was %.2f, now %.2f\n", 1806 stem_edge-hints->axis[dim].edges, stem_edge->opos / 64.0, 1807 stem_edge->pos / 64.0, dist / 64.0, fitted_width / 64.0 )); 1808 } 1809 1810 1811 static void af_latin2_align_serif_edge(AF_GlyphHints hints,AF_Edge base,AF_Edge serif)1812 af_latin2_align_serif_edge( AF_GlyphHints hints, 1813 AF_Edge base, 1814 AF_Edge serif ) 1815 { 1816 FT_UNUSED( hints ); 1817 1818 serif->pos = base->pos + ( serif->opos - base->opos ); 1819 } 1820 1821 1822 /*************************************************************************/ 1823 /*************************************************************************/ 1824 /*************************************************************************/ 1825 /**** ****/ 1826 /**** E D G E H I N T I N G ****/ 1827 /**** ****/ 1828 /*************************************************************************/ 1829 /*************************************************************************/ 1830 /*************************************************************************/ 1831 1832 1833 FT_LOCAL_DEF( void ) af_latin2_hint_edges(AF_GlyphHints hints,AF_Dimension dim)1834 af_latin2_hint_edges( AF_GlyphHints hints, 1835 AF_Dimension dim ) 1836 { 1837 AF_AxisHints axis = &hints->axis[dim]; 1838 AF_Edge edges = axis->edges; 1839 AF_Edge edge_limit = edges + axis->num_edges; 1840 AF_Edge edge; 1841 AF_Edge anchor = 0; 1842 FT_Int has_serifs = 0; 1843 FT_Pos anchor_drift = 0; 1844 1845 1846 1847 FT_TRACE5(( "==== hinting %s edges =====\n", 1848 dim == AF_DIMENSION_HORZ ? "vertical" : "horizontal" )); 1849 1850 /* we begin by aligning all stems relative to the blue zone */ 1851 /* if needed -- that's only for horizontal edges */ 1852 1853 if ( dim == AF_DIMENSION_VERT && AF_HINTS_DO_BLUES( hints ) ) 1854 { 1855 for ( edge = edges; edge < edge_limit; edge++ ) 1856 { 1857 AF_Width blue; 1858 AF_Edge edge1, edge2; 1859 1860 1861 if ( edge->flags & AF_EDGE_DONE ) 1862 continue; 1863 1864 blue = edge->blue_edge; 1865 edge1 = NULL; 1866 edge2 = edge->link; 1867 1868 if ( blue ) 1869 { 1870 edge1 = edge; 1871 } 1872 else if ( edge2 && edge2->blue_edge ) 1873 { 1874 blue = edge2->blue_edge; 1875 edge1 = edge2; 1876 edge2 = edge; 1877 } 1878 1879 if ( !edge1 ) 1880 continue; 1881 1882 FT_TRACE5(( "BLUE: edge %d (opos=%.2f) snapped to (%.2f), " 1883 "was (%.2f)\n", 1884 edge1-edges, edge1->opos / 64.0, blue->fit / 64.0, 1885 edge1->pos / 64.0 )); 1886 1887 edge1->pos = blue->fit; 1888 edge1->flags |= AF_EDGE_DONE; 1889 1890 if ( edge2 && !edge2->blue_edge ) 1891 { 1892 af_latin2_align_linked_edge( hints, dim, edge1, edge2 ); 1893 edge2->flags |= AF_EDGE_DONE; 1894 } 1895 1896 if ( !anchor ) 1897 { 1898 anchor = edge; 1899 1900 anchor_drift = ( anchor->pos - anchor->opos ); 1901 if ( edge2 ) 1902 anchor_drift = ( anchor_drift + 1903 ( edge2->pos - edge2->opos ) ) >> 1; 1904 } 1905 } 1906 } 1907 1908 /* now we will align all stem edges, trying to maintain the */ 1909 /* relative order of stems in the glyph */ 1910 for ( edge = edges; edge < edge_limit; edge++ ) 1911 { 1912 AF_Edge edge2; 1913 1914 1915 if ( edge->flags & AF_EDGE_DONE ) 1916 continue; 1917 1918 /* skip all non-stem edges */ 1919 edge2 = edge->link; 1920 if ( !edge2 ) 1921 { 1922 has_serifs++; 1923 continue; 1924 } 1925 1926 /* now align the stem */ 1927 1928 /* this should not happen, but it's better to be safe */ 1929 if ( edge2->blue_edge ) 1930 { 1931 FT_TRACE5(( "ASSERTION FAILED for edge %d\n", edge2-edges )); 1932 1933 af_latin2_align_linked_edge( hints, dim, edge2, edge ); 1934 edge->flags |= AF_EDGE_DONE; 1935 continue; 1936 } 1937 1938 if ( !anchor ) 1939 { 1940 FT_Pos org_len, org_center, cur_len; 1941 FT_Pos cur_pos1, error1, error2, u_off, d_off; 1942 1943 1944 org_len = edge2->opos - edge->opos; 1945 cur_len = af_latin2_compute_stem_width( 1946 hints, dim, org_len, 1947 (AF_Edge_Flags)edge->flags, 1948 (AF_Edge_Flags)edge2->flags ); 1949 if ( cur_len <= 64 ) 1950 u_off = d_off = 32; 1951 else 1952 { 1953 u_off = 38; 1954 d_off = 26; 1955 } 1956 1957 if ( cur_len < 96 ) 1958 { 1959 org_center = edge->opos + ( org_len >> 1 ); 1960 1961 cur_pos1 = FT_PIX_ROUND( org_center ); 1962 1963 error1 = org_center - ( cur_pos1 - u_off ); 1964 if ( error1 < 0 ) 1965 error1 = -error1; 1966 1967 error2 = org_center - ( cur_pos1 + d_off ); 1968 if ( error2 < 0 ) 1969 error2 = -error2; 1970 1971 if ( error1 < error2 ) 1972 cur_pos1 -= u_off; 1973 else 1974 cur_pos1 += d_off; 1975 1976 edge->pos = cur_pos1 - cur_len / 2; 1977 edge2->pos = edge->pos + cur_len; 1978 } 1979 else 1980 edge->pos = FT_PIX_ROUND( edge->opos ); 1981 1982 FT_TRACE5(( "ANCHOR: edge %d (opos=%.2f) and %d (opos=%.2f)" 1983 " snapped to (%.2f) (%.2f)\n", 1984 edge-edges, edge->opos / 64.0, 1985 edge2-edges, edge2->opos / 64.0, 1986 edge->pos / 64.0, edge2->pos / 64.0 )); 1987 anchor = edge; 1988 1989 edge->flags |= AF_EDGE_DONE; 1990 1991 af_latin2_align_linked_edge( hints, dim, edge, edge2 ); 1992 1993 edge2->flags |= AF_EDGE_DONE; 1994 1995 anchor_drift = ( ( anchor->pos - anchor->opos ) + 1996 ( edge2->pos - edge2->opos ) ) >> 1; 1997 1998 FT_TRACE5(( "DRIFT: %.2f\n", anchor_drift/64.0 )); 1999 } 2000 else 2001 { 2002 FT_Pos org_pos, org_len, org_center, cur_center, cur_len; 2003 FT_Pos org_left, org_right; 2004 2005 2006 org_pos = edge->opos + anchor_drift; 2007 org_len = edge2->opos - edge->opos; 2008 org_center = org_pos + ( org_len >> 1 ); 2009 2010 cur_len = af_latin2_compute_stem_width( 2011 hints, dim, org_len, 2012 (AF_Edge_Flags)edge->flags, 2013 (AF_Edge_Flags)edge2->flags ); 2014 2015 org_left = org_pos + ( ( org_len - cur_len ) >> 1 ); 2016 org_right = org_pos + ( ( org_len + cur_len ) >> 1 ); 2017 2018 FT_TRACE5(( "ALIGN: left=%.2f right=%.2f ", 2019 org_left / 64.0, org_right / 64.0 )); 2020 cur_center = org_center; 2021 2022 if ( edge2->flags & AF_EDGE_DONE ) 2023 { 2024 FT_TRACE5(( "\n" )); 2025 edge->pos = edge2->pos - cur_len; 2026 } 2027 else 2028 { 2029 /* we want to compare several displacement, and choose 2030 * the one that increases fitness while minimizing 2031 * distortion as well 2032 */ 2033 FT_Pos displacements[6], scores[6], org, fit, delta; 2034 FT_UInt count = 0; 2035 2036 /* note: don't even try to fit tiny stems */ 2037 if ( cur_len < 32 ) 2038 { 2039 FT_TRACE5(( "tiny stem\n" )); 2040 goto AlignStem; 2041 } 2042 2043 /* if the span is within a single pixel, don't touch it */ 2044 if ( FT_PIX_FLOOR( org_left ) == FT_PIX_CEIL( org_right ) ) 2045 { 2046 FT_TRACE5(( "single pixel stem\n" )); 2047 goto AlignStem; 2048 } 2049 2050 if ( cur_len <= 96 ) 2051 { 2052 /* we want to avoid the absolute worst case which is 2053 * when the left and right edges of the span each represent 2054 * about 50% of the gray. we'd better want to change this 2055 * to 25/75%, since this is much more pleasant to the eye with 2056 * very acceptable distortion 2057 */ 2058 FT_Pos frac_left = org_left & 63; 2059 FT_Pos frac_right = org_right & 63; 2060 2061 if ( frac_left >= 22 && frac_left <= 42 && 2062 frac_right >= 22 && frac_right <= 42 ) 2063 { 2064 org = frac_left; 2065 fit = ( org <= 32 ) ? 16 : 48; 2066 delta = FT_ABS( fit - org ); 2067 displacements[count] = fit - org; 2068 scores[count++] = delta; 2069 FT_TRACE5(( "dispA=%.2f (%d) ", ( fit - org ) / 64.0, delta )); 2070 2071 org = frac_right; 2072 fit = ( org <= 32 ) ? 16 : 48; 2073 delta = FT_ABS( fit - org ); 2074 displacements[count] = fit - org; 2075 scores[count++] = delta; 2076 FT_TRACE5(( "dispB=%.2f (%d) ", ( fit - org ) / 64.0, delta )); 2077 } 2078 } 2079 2080 /* snapping the left edge to the grid */ 2081 org = org_left; 2082 fit = FT_PIX_ROUND( org ); 2083 delta = FT_ABS( fit - org ); 2084 displacements[count] = fit - org; 2085 scores[count++] = delta; 2086 FT_TRACE5(( "dispC=%.2f (%d) ", ( fit - org ) / 64.0, delta )); 2087 2088 /* snapping the right edge to the grid */ 2089 org = org_right; 2090 fit = FT_PIX_ROUND( org ); 2091 delta = FT_ABS( fit - org ); 2092 displacements[count] = fit - org; 2093 scores[count++] = delta; 2094 FT_TRACE5(( "dispD=%.2f (%d) ", ( fit - org ) / 64.0, delta )); 2095 2096 /* now find the best displacement */ 2097 { 2098 FT_Pos best_score = scores[0]; 2099 FT_Pos best_disp = displacements[0]; 2100 FT_UInt nn; 2101 2102 for ( nn = 1; nn < count; nn++ ) 2103 { 2104 if ( scores[nn] < best_score ) 2105 { 2106 best_score = scores[nn]; 2107 best_disp = displacements[nn]; 2108 } 2109 } 2110 2111 cur_center = org_center + best_disp; 2112 } 2113 FT_TRACE5(( "\n" )); 2114 } 2115 2116 AlignStem: 2117 edge->pos = cur_center - ( cur_len >> 1 ); 2118 edge2->pos = edge->pos + cur_len; 2119 2120 FT_TRACE5(( "STEM1: %d (opos=%.2f) to %d (opos=%.2f)" 2121 " snapped to (%.2f) and (%.2f)," 2122 " org_len=%.2f cur_len=%.2f\n", 2123 edge-edges, edge->opos / 64.0, 2124 edge2-edges, edge2->opos / 64.0, 2125 edge->pos / 64.0, edge2->pos / 64.0, 2126 org_len / 64.0, cur_len / 64.0 )); 2127 2128 edge->flags |= AF_EDGE_DONE; 2129 edge2->flags |= AF_EDGE_DONE; 2130 2131 if ( edge > edges && edge->pos < edge[-1].pos ) 2132 { 2133 FT_TRACE5(( "BOUND: %d (pos=%.2f) to (%.2f)\n", 2134 edge-edges, edge->pos / 64.0, edge[-1].pos / 64.0 )); 2135 edge->pos = edge[-1].pos; 2136 } 2137 } 2138 } 2139 2140 /* make sure that lowercase m's maintain their symmetry */ 2141 2142 /* In general, lowercase m's have six vertical edges if they are sans */ 2143 /* serif, or twelve if they are with serifs. This implementation is */ 2144 /* based on that assumption, and seems to work very well with most */ 2145 /* faces. However, if for a certain face this assumption is not */ 2146 /* true, the m is just rendered like before. In addition, any stem */ 2147 /* correction will only be applied to symmetrical glyphs (even if the */ 2148 /* glyph is not an m), so the potential for unwanted distortion is */ 2149 /* relatively low. */ 2150 2151 /* We don't handle horizontal edges since we can't easily assure that */ 2152 /* the third (lowest) stem aligns with the base line; it might end up */ 2153 /* one pixel higher or lower. */ 2154 2155 #if 0 2156 { 2157 FT_Int n_edges = edge_limit - edges; 2158 2159 2160 if ( dim == AF_DIMENSION_HORZ && ( n_edges == 6 || n_edges == 12 ) ) 2161 { 2162 AF_Edge edge1, edge2, edge3; 2163 FT_Pos dist1, dist2, span, delta; 2164 2165 2166 if ( n_edges == 6 ) 2167 { 2168 edge1 = edges; 2169 edge2 = edges + 2; 2170 edge3 = edges + 4; 2171 } 2172 else 2173 { 2174 edge1 = edges + 1; 2175 edge2 = edges + 5; 2176 edge3 = edges + 9; 2177 } 2178 2179 dist1 = edge2->opos - edge1->opos; 2180 dist2 = edge3->opos - edge2->opos; 2181 2182 span = dist1 - dist2; 2183 if ( span < 0 ) 2184 span = -span; 2185 2186 if ( span < 8 ) 2187 { 2188 delta = edge3->pos - ( 2 * edge2->pos - edge1->pos ); 2189 edge3->pos -= delta; 2190 if ( edge3->link ) 2191 edge3->link->pos -= delta; 2192 2193 /* move the serifs along with the stem */ 2194 if ( n_edges == 12 ) 2195 { 2196 ( edges + 8 )->pos -= delta; 2197 ( edges + 11 )->pos -= delta; 2198 } 2199 2200 edge3->flags |= AF_EDGE_DONE; 2201 if ( edge3->link ) 2202 edge3->link->flags |= AF_EDGE_DONE; 2203 } 2204 } 2205 } 2206 #endif 2207 2208 if ( has_serifs || !anchor ) 2209 { 2210 /* 2211 * now hint the remaining edges (serifs and single) in order 2212 * to complete our processing 2213 */ 2214 for ( edge = edges; edge < edge_limit; edge++ ) 2215 { 2216 FT_Pos delta; 2217 2218 2219 if ( edge->flags & AF_EDGE_DONE ) 2220 continue; 2221 2222 delta = 1000; 2223 2224 if ( edge->serif ) 2225 { 2226 delta = edge->serif->opos - edge->opos; 2227 if ( delta < 0 ) 2228 delta = -delta; 2229 } 2230 2231 if ( delta < 64 + 16 ) 2232 { 2233 af_latin2_align_serif_edge( hints, edge->serif, edge ); 2234 FT_TRACE5(( "SERIF: edge %d (opos=%.2f) serif to %d (opos=%.2f)" 2235 " aligned to (%.2f)\n", 2236 edge-edges, edge->opos / 64.0, 2237 edge->serif - edges, edge->serif->opos / 64.0, 2238 edge->pos / 64.0 )); 2239 } 2240 else if ( !anchor ) 2241 { 2242 FT_TRACE5(( "SERIF_ANCHOR: edge %d (opos=%.2f)" 2243 " snapped to (%.2f)\n", 2244 edge-edges, edge->opos / 64.0, edge->pos / 64.0 )); 2245 edge->pos = FT_PIX_ROUND( edge->opos ); 2246 anchor = edge; 2247 } 2248 else 2249 { 2250 AF_Edge before, after; 2251 2252 2253 for ( before = edge - 1; before >= edges; before-- ) 2254 if ( before->flags & AF_EDGE_DONE ) 2255 break; 2256 2257 for ( after = edge + 1; after < edge_limit; after++ ) 2258 if ( after->flags & AF_EDGE_DONE ) 2259 break; 2260 2261 if ( before >= edges && before < edge && 2262 after < edge_limit && after > edge ) 2263 { 2264 if ( after->opos == before->opos ) 2265 edge->pos = before->pos; 2266 else 2267 edge->pos = before->pos + 2268 FT_MulDiv( edge->opos - before->opos, 2269 after->pos - before->pos, 2270 after->opos - before->opos ); 2271 FT_TRACE5(( "SERIF_LINK1: edge %d (opos=%.2f) snapped to (%.2f)" 2272 " from %d (opos=%.2f)\n", 2273 edge-edges, edge->opos / 64.0, edge->pos / 64.0, 2274 before - edges, before->opos / 64.0 )); 2275 } 2276 else 2277 { 2278 edge->pos = anchor->pos + 2279 ( ( edge->opos - anchor->opos + 16 ) & ~31 ); 2280 2281 FT_TRACE5(( "SERIF_LINK2: edge %d (opos=%.2f)" 2282 " snapped to (%.2f)\n", 2283 edge-edges, edge->opos / 64.0, edge->pos / 64.0 )); 2284 } 2285 } 2286 2287 edge->flags |= AF_EDGE_DONE; 2288 2289 if ( edge > edges && edge->pos < edge[-1].pos ) 2290 edge->pos = edge[-1].pos; 2291 2292 if ( edge + 1 < edge_limit && 2293 edge[1].flags & AF_EDGE_DONE && 2294 edge->pos > edge[1].pos ) 2295 edge->pos = edge[1].pos; 2296 } 2297 } 2298 } 2299 2300 2301 static FT_Error af_latin2_hints_apply(AF_GlyphHints hints,FT_Outline * outline,AF_LatinMetrics metrics)2302 af_latin2_hints_apply( AF_GlyphHints hints, 2303 FT_Outline* outline, 2304 AF_LatinMetrics metrics ) 2305 { 2306 FT_Error error; 2307 int dim; 2308 2309 2310 error = af_glyph_hints_reload( hints, outline ); 2311 if ( error ) 2312 goto Exit; 2313 2314 /* analyze glyph outline */ 2315 #ifdef AF_CONFIG_OPTION_USE_WARPER 2316 if ( metrics->root.scaler.render_mode == FT_RENDER_MODE_LIGHT || 2317 AF_HINTS_DO_HORIZONTAL( hints ) ) 2318 #else 2319 if ( AF_HINTS_DO_HORIZONTAL( hints ) ) 2320 #endif 2321 { 2322 error = af_latin2_hints_detect_features( hints, AF_DIMENSION_HORZ ); 2323 if ( error ) 2324 goto Exit; 2325 } 2326 2327 if ( AF_HINTS_DO_VERTICAL( hints ) ) 2328 { 2329 error = af_latin2_hints_detect_features( hints, AF_DIMENSION_VERT ); 2330 if ( error ) 2331 goto Exit; 2332 2333 af_latin2_hints_compute_blue_edges( hints, metrics ); 2334 } 2335 2336 /* grid-fit the outline */ 2337 for ( dim = 0; dim < AF_DIMENSION_MAX; dim++ ) 2338 { 2339 #ifdef AF_CONFIG_OPTION_USE_WARPER 2340 if ( ( dim == AF_DIMENSION_HORZ && 2341 metrics->root.scaler.render_mode == FT_RENDER_MODE_LIGHT ) ) 2342 { 2343 AF_WarperRec warper; 2344 FT_Fixed scale; 2345 FT_Pos delta; 2346 2347 2348 af_warper_compute( &warper, hints, dim, &scale, &delta ); 2349 af_glyph_hints_scale_dim( hints, dim, scale, delta ); 2350 continue; 2351 } 2352 #endif 2353 2354 if ( ( dim == AF_DIMENSION_HORZ && AF_HINTS_DO_HORIZONTAL( hints ) ) || 2355 ( dim == AF_DIMENSION_VERT && AF_HINTS_DO_VERTICAL( hints ) ) ) 2356 { 2357 af_latin2_hint_edges( hints, (AF_Dimension)dim ); 2358 af_glyph_hints_align_edge_points( hints, (AF_Dimension)dim ); 2359 af_glyph_hints_align_strong_points( hints, (AF_Dimension)dim ); 2360 af_glyph_hints_align_weak_points( hints, (AF_Dimension)dim ); 2361 } 2362 } 2363 af_glyph_hints_save( hints, outline ); 2364 2365 Exit: 2366 return error; 2367 } 2368 2369 2370 /*************************************************************************/ 2371 /*************************************************************************/ 2372 /***** *****/ 2373 /***** L A T I N S C R I P T C L A S S *****/ 2374 /***** *****/ 2375 /*************************************************************************/ 2376 /*************************************************************************/ 2377 2378 2379 AF_DEFINE_WRITING_SYSTEM_CLASS( 2380 af_latin2_writing_system_class, 2381 2382 AF_WRITING_SYSTEM_LATIN2, 2383 2384 sizeof ( AF_LatinMetricsRec ), 2385 2386 (AF_WritingSystem_InitMetricsFunc) af_latin2_metrics_init, 2387 (AF_WritingSystem_ScaleMetricsFunc)af_latin2_metrics_scale, 2388 (AF_WritingSystem_DoneMetricsFunc) NULL, 2389 2390 (AF_WritingSystem_InitHintsFunc) af_latin2_hints_init, 2391 (AF_WritingSystem_ApplyHintsFunc) af_latin2_hints_apply 2392 ) 2393 2394 2395 /* END */ 2396