1 /***************************************************************************/ 2 /* */ 3 /* aflatin.c */ 4 /* */ 5 /* Auto-fitter hinting routines for latin script (body). */ 6 /* */ 7 /* Copyright 2003-2011 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 <ft2build.h> 20 #include FT_ADVANCES_H 21 #include FT_INTERNAL_DEBUG_H 22 23 #include "aflatin.h" 24 #include "aferrors.h" 25 26 27 #ifdef AF_CONFIG_OPTION_USE_WARPER 28 #include "afwarp.h" 29 #endif 30 31 32 /*************************************************************************/ 33 /* */ 34 /* The macro FT_COMPONENT is used in trace mode. It is an implicit */ 35 /* parameter of the FT_TRACE() and FT_ERROR() macros, used to print/log */ 36 /* messages during execution. */ 37 /* */ 38 #undef FT_COMPONENT 39 #define FT_COMPONENT trace_aflatin 40 41 42 /*************************************************************************/ 43 /*************************************************************************/ 44 /***** *****/ 45 /***** L A T I N G L O B A L M E T R I C S *****/ 46 /***** *****/ 47 /*************************************************************************/ 48 /*************************************************************************/ 49 50 51 /* Find segments and links, compute all stem widths, and initialize */ 52 /* standard width and height for the glyph with given charcode. */ 53 54 FT_LOCAL_DEF( void ) af_latin_metrics_init_widths(AF_LatinMetrics metrics,FT_Face face,FT_ULong charcode)55 af_latin_metrics_init_widths( AF_LatinMetrics metrics, 56 FT_Face face, 57 FT_ULong charcode ) 58 { 59 /* scan the array of segments in each direction */ 60 AF_GlyphHintsRec hints[1]; 61 62 63 af_glyph_hints_init( hints, face->memory ); 64 65 metrics->axis[AF_DIMENSION_HORZ].width_count = 0; 66 metrics->axis[AF_DIMENSION_VERT].width_count = 0; 67 68 { 69 FT_Error error; 70 FT_UInt glyph_index; 71 int dim; 72 AF_LatinMetricsRec dummy[1]; 73 AF_Scaler scaler = &dummy->root.scaler; 74 75 76 glyph_index = FT_Get_Char_Index( face, charcode ); 77 if ( glyph_index == 0 ) 78 goto Exit; 79 80 error = FT_Load_Glyph( face, glyph_index, FT_LOAD_NO_SCALE ); 81 if ( error || face->glyph->outline.n_points <= 0 ) 82 goto Exit; 83 84 FT_ZERO( dummy ); 85 86 dummy->units_per_em = metrics->units_per_em; 87 88 scaler->x_scale = 0x10000L; 89 scaler->y_scale = 0x10000L; 90 scaler->x_delta = 0; 91 scaler->y_delta = 0; 92 93 scaler->face = face; 94 scaler->render_mode = FT_RENDER_MODE_NORMAL; 95 scaler->flags = 0; 96 97 af_glyph_hints_rescale( hints, (AF_ScriptMetrics)dummy ); 98 99 error = af_glyph_hints_reload( hints, &face->glyph->outline ); 100 if ( error ) 101 goto Exit; 102 103 for ( dim = 0; dim < AF_DIMENSION_MAX; dim++ ) 104 { 105 AF_LatinAxis axis = &metrics->axis[dim]; 106 AF_AxisHints axhints = &hints->axis[dim]; 107 AF_Segment seg, limit, link; 108 FT_UInt num_widths = 0; 109 110 111 error = af_latin_hints_compute_segments( hints, 112 (AF_Dimension)dim ); 113 if ( error ) 114 goto Exit; 115 116 af_latin_hints_link_segments( hints, 117 (AF_Dimension)dim ); 118 119 seg = axhints->segments; 120 limit = seg + axhints->num_segments; 121 122 for ( ; seg < limit; seg++ ) 123 { 124 link = seg->link; 125 126 /* we only consider stem segments there! */ 127 if ( link && link->link == seg && link > seg ) 128 { 129 FT_Pos dist; 130 131 132 dist = seg->pos - link->pos; 133 if ( dist < 0 ) 134 dist = -dist; 135 136 if ( num_widths < AF_LATIN_MAX_WIDTHS ) 137 axis->widths[num_widths++].org = dist; 138 } 139 } 140 141 af_sort_widths( num_widths, axis->widths ); 142 axis->width_count = num_widths; 143 } 144 145 Exit: 146 for ( dim = 0; dim < AF_DIMENSION_MAX; dim++ ) 147 { 148 AF_LatinAxis axis = &metrics->axis[dim]; 149 FT_Pos stdw; 150 151 152 stdw = ( axis->width_count > 0 ) 153 ? axis->widths[0].org 154 : AF_LATIN_CONSTANT( metrics, 50 ); 155 156 /* let's try 20% of the smallest width */ 157 axis->edge_distance_threshold = stdw / 5; 158 axis->standard_width = stdw; 159 axis->extra_light = 0; 160 } 161 } 162 163 af_glyph_hints_done( hints ); 164 } 165 166 167 168 #define AF_LATIN_MAX_TEST_CHARACTERS 12 169 170 171 static const char af_latin_blue_chars[AF_LATIN_MAX_BLUES] 172 [AF_LATIN_MAX_TEST_CHARACTERS + 1] = 173 { 174 "THEZOCQS", 175 "HEZLOCUS", 176 "fijkdbh", 177 "xzroesc", 178 "xzroesc", 179 "pqgjy" 180 }; 181 182 183 /* Find all blue zones. Flat segments give the reference points, */ 184 /* round segments the overshoot positions. */ 185 186 static void af_latin_metrics_init_blues(AF_LatinMetrics metrics,FT_Face face)187 af_latin_metrics_init_blues( AF_LatinMetrics metrics, 188 FT_Face face ) 189 { 190 FT_Pos flats [AF_LATIN_MAX_TEST_CHARACTERS]; 191 FT_Pos rounds[AF_LATIN_MAX_TEST_CHARACTERS]; 192 FT_Int num_flats; 193 FT_Int num_rounds; 194 FT_Int bb; 195 AF_LatinBlue blue; 196 FT_Error error; 197 AF_LatinAxis axis = &metrics->axis[AF_DIMENSION_VERT]; 198 FT_GlyphSlot glyph = face->glyph; 199 200 201 /* we compute the blues simply by loading each character from the */ 202 /* `af_latin_blue_chars[blues]' string, then finding its top-most or */ 203 /* bottom-most points (depending on `AF_IS_TOP_BLUE') */ 204 205 FT_TRACE5(( "blue zones computation\n" )); 206 FT_TRACE5(( "------------------------------------------------\n" )); 207 208 for ( bb = 0; bb < AF_LATIN_BLUE_MAX; bb++ ) 209 { 210 const char* p = af_latin_blue_chars[bb]; 211 const char* limit = p + AF_LATIN_MAX_TEST_CHARACTERS; 212 FT_Pos* blue_ref; 213 FT_Pos* blue_shoot; 214 215 216 FT_TRACE5(( "blue %3d: ", bb )); 217 218 num_flats = 0; 219 num_rounds = 0; 220 221 for ( ; p < limit && *p; p++ ) 222 { 223 FT_UInt glyph_index; 224 FT_Pos best_y; /* same as points.y */ 225 FT_Int best_point, best_first, best_last; 226 FT_Vector* points; 227 FT_Bool round = 0; 228 229 230 FT_TRACE5(( "'%c'", *p )); 231 232 /* load the character in the face -- skip unknown or empty ones */ 233 glyph_index = FT_Get_Char_Index( face, (FT_UInt)*p ); 234 if ( glyph_index == 0 ) 235 continue; 236 237 error = FT_Load_Glyph( face, glyph_index, FT_LOAD_NO_SCALE ); 238 if ( error || glyph->outline.n_points <= 0 ) 239 continue; 240 241 /* now compute min or max point indices and coordinates */ 242 points = glyph->outline.points; 243 best_point = -1; 244 best_y = 0; /* make compiler happy */ 245 best_first = 0; /* ditto */ 246 best_last = 0; /* ditto */ 247 248 { 249 FT_Int nn; 250 FT_Int first = 0; 251 FT_Int last = -1; 252 253 254 for ( nn = 0; 255 nn < glyph->outline.n_contours; 256 first = last + 1, nn++ ) 257 { 258 FT_Int old_best_point = best_point; 259 FT_Int pp; 260 261 262 last = glyph->outline.contours[nn]; 263 264 /* Avoid single-point contours since they are never rasterized. */ 265 /* In some fonts, they correspond to mark attachment points */ 266 /* which are way outside of the glyph's real outline. */ 267 if ( last <= first ) 268 continue; 269 270 if ( AF_LATIN_IS_TOP_BLUE( bb ) ) 271 { 272 for ( pp = first; pp <= last; pp++ ) 273 if ( best_point < 0 || points[pp].y > best_y ) 274 { 275 best_point = pp; 276 best_y = points[pp].y; 277 } 278 } 279 else 280 { 281 for ( pp = first; pp <= last; pp++ ) 282 if ( best_point < 0 || points[pp].y < best_y ) 283 { 284 best_point = pp; 285 best_y = points[pp].y; 286 } 287 } 288 289 if ( best_point != old_best_point ) 290 { 291 best_first = first; 292 best_last = last; 293 } 294 } 295 FT_TRACE5(( "%5d", best_y )); 296 } 297 298 /* now check whether the point belongs to a straight or round */ 299 /* segment; we first need to find in which contour the extremum */ 300 /* lies, then inspect its previous and next points */ 301 if ( best_point >= 0 ) 302 { 303 FT_Int prev, next; 304 FT_Pos dist; 305 306 307 /* now look for the previous and next points that are not on the */ 308 /* same Y coordinate. Threshold the `closeness'... */ 309 prev = best_point; 310 next = prev; 311 312 do 313 { 314 if ( prev > best_first ) 315 prev--; 316 else 317 prev = best_last; 318 319 dist = points[prev].y - best_y; 320 if ( dist < -5 || dist > 5 ) 321 break; 322 323 } while ( prev != best_point ); 324 325 do 326 { 327 if ( next < best_last ) 328 next++; 329 else 330 next = best_first; 331 332 dist = points[next].y - best_y; 333 if ( dist < -5 || dist > 5 ) 334 break; 335 336 } while ( next != best_point ); 337 338 /* now set the `round' flag depending on the segment's kind */ 339 round = FT_BOOL( 340 FT_CURVE_TAG( glyph->outline.tags[prev] ) != FT_CURVE_TAG_ON || 341 FT_CURVE_TAG( glyph->outline.tags[next] ) != FT_CURVE_TAG_ON ); 342 343 FT_TRACE5(( "%c ", round ? 'r' : 'f' )); 344 } 345 346 if ( round ) 347 rounds[num_rounds++] = best_y; 348 else 349 flats[num_flats++] = best_y; 350 } 351 352 FT_TRACE5(( "\n" )); 353 354 if ( num_flats == 0 && num_rounds == 0 ) 355 { 356 /* 357 * we couldn't find a single glyph to compute this blue zone, 358 * we will simply ignore it then 359 */ 360 FT_TRACE5(( "empty\n" )); 361 continue; 362 } 363 364 /* we have computed the contents of the `rounds' and `flats' tables, */ 365 /* now determine the reference and overshoot position of the blue -- */ 366 /* we simply take the median value after a simple sort */ 367 af_sort_pos( num_rounds, rounds ); 368 af_sort_pos( num_flats, flats ); 369 370 blue = &axis->blues[axis->blue_count]; 371 blue_ref = &blue->ref.org; 372 blue_shoot = &blue->shoot.org; 373 374 axis->blue_count++; 375 376 if ( num_flats == 0 ) 377 { 378 *blue_ref = 379 *blue_shoot = rounds[num_rounds / 2]; 380 } 381 else if ( num_rounds == 0 ) 382 { 383 *blue_ref = 384 *blue_shoot = flats[num_flats / 2]; 385 } 386 else 387 { 388 *blue_ref = flats[num_flats / 2]; 389 *blue_shoot = rounds[num_rounds / 2]; 390 } 391 392 /* there are sometimes problems: if the overshoot position of top */ 393 /* zones is under its reference position, or the opposite for bottom */ 394 /* zones. We must thus check everything there and correct the errors */ 395 if ( *blue_shoot != *blue_ref ) 396 { 397 FT_Pos ref = *blue_ref; 398 FT_Pos shoot = *blue_shoot; 399 FT_Bool over_ref = FT_BOOL( shoot > ref ); 400 401 402 if ( AF_LATIN_IS_TOP_BLUE( bb ) ^ over_ref ) 403 *blue_ref = 404 *blue_shoot = ( shoot + ref ) / 2; 405 } 406 407 blue->flags = 0; 408 if ( AF_LATIN_IS_TOP_BLUE( bb ) ) 409 blue->flags |= AF_LATIN_BLUE_TOP; 410 411 /* 412 * The following flag is used later to adjust the y and x scales 413 * in order to optimize the pixel grid alignment of the top of small 414 * letters. 415 */ 416 if ( bb == AF_LATIN_BLUE_SMALL_TOP ) 417 blue->flags |= AF_LATIN_BLUE_ADJUSTMENT; 418 419 FT_TRACE5(( "-- ref = %ld, shoot = %ld\n", *blue_ref, *blue_shoot )); 420 } 421 422 FT_TRACE5(( "\n" )); 423 424 return; 425 } 426 427 428 /* Check whether all ASCII digits have the same advance width. */ 429 430 FT_LOCAL_DEF( void ) af_latin_metrics_check_digits(AF_LatinMetrics metrics,FT_Face face)431 af_latin_metrics_check_digits( AF_LatinMetrics metrics, 432 FT_Face face ) 433 { 434 FT_UInt i; 435 FT_Bool started = 0, same_width = 1; 436 FT_Fixed advance, old_advance = 0; 437 438 439 /* 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 /* Initialize global metrics. */ 476 477 FT_LOCAL_DEF( FT_Error ) af_latin_metrics_init(AF_LatinMetrics metrics,FT_Face face)478 af_latin_metrics_init( AF_LatinMetrics metrics, 479 FT_Face face ) 480 { 481 FT_Error error = AF_Err_Ok; 482 FT_CharMap oldmap = face->charmap; 483 FT_UInt ee; 484 485 static const FT_Encoding latin_encodings[] = 486 { 487 FT_ENCODING_UNICODE, 488 FT_ENCODING_APPLE_ROMAN, 489 FT_ENCODING_ADOBE_STANDARD, 490 FT_ENCODING_ADOBE_LATIN_1, 491 492 FT_ENCODING_NONE /* end of list */ 493 }; 494 495 496 metrics->units_per_em = face->units_per_EM; 497 498 /* do we have a latin charmap in there? */ 499 for ( ee = 0; latin_encodings[ee] != FT_ENCODING_NONE; ee++ ) 500 { 501 error = FT_Select_Charmap( face, latin_encodings[ee] ); 502 if ( !error ) 503 break; 504 } 505 506 if ( !error ) 507 { 508 /* For now, compute the standard width and height from the `o'. */ 509 af_latin_metrics_init_widths( metrics, face, 'o' ); 510 af_latin_metrics_init_blues( metrics, face ); 511 af_latin_metrics_check_digits( metrics, face ); 512 } 513 514 FT_Set_Charmap( face, oldmap ); 515 return AF_Err_Ok; 516 } 517 518 519 /* Adjust scaling value, then scale and shift widths */ 520 /* and blue zones (if applicable) for given dimension. */ 521 522 static void af_latin_metrics_scale_dim(AF_LatinMetrics metrics,AF_Scaler scaler,AF_Dimension dim)523 af_latin_metrics_scale_dim( AF_LatinMetrics metrics, 524 AF_Scaler scaler, 525 AF_Dimension dim ) 526 { 527 FT_Fixed scale; 528 FT_Pos delta; 529 AF_LatinAxis axis; 530 FT_UInt nn; 531 532 533 if ( dim == AF_DIMENSION_HORZ ) 534 { 535 scale = scaler->x_scale; 536 delta = scaler->x_delta; 537 } 538 else 539 { 540 scale = scaler->y_scale; 541 delta = scaler->y_delta; 542 } 543 544 axis = &metrics->axis[dim]; 545 546 if ( axis->org_scale == scale && axis->org_delta == delta ) 547 return; 548 549 axis->org_scale = scale; 550 axis->org_delta = delta; 551 552 /* 553 * correct X and Y scale to optimize the alignment of the top of small 554 * letters to the pixel grid 555 */ 556 { 557 AF_LatinAxis Axis = &metrics->axis[AF_DIMENSION_VERT]; 558 AF_LatinBlue blue = NULL; 559 560 561 for ( nn = 0; nn < Axis->blue_count; nn++ ) 562 { 563 if ( Axis->blues[nn].flags & AF_LATIN_BLUE_ADJUSTMENT ) 564 { 565 blue = &Axis->blues[nn]; 566 break; 567 } 568 } 569 570 if ( blue ) 571 { 572 FT_Pos scaled = FT_MulFix( blue->shoot.org, scaler->y_scale ); 573 FT_Pos fitted = ( scaled + 40 ) & ~63; 574 575 576 if ( scaled != fitted ) 577 { 578 #if 0 579 if ( dim == AF_DIMENSION_HORZ ) 580 { 581 if ( fitted < scaled ) 582 scale -= scale / 50; /* scale *= 0.98 */ 583 } 584 else 585 #endif 586 if ( dim == AF_DIMENSION_VERT ) 587 scale = FT_MulDiv( scale, fitted, scaled ); 588 } 589 } 590 } 591 592 axis->scale = scale; 593 axis->delta = delta; 594 595 if ( dim == AF_DIMENSION_HORZ ) 596 { 597 metrics->root.scaler.x_scale = scale; 598 metrics->root.scaler.x_delta = delta; 599 } 600 else 601 { 602 metrics->root.scaler.y_scale = scale; 603 metrics->root.scaler.y_delta = delta; 604 } 605 606 /* scale the widths */ 607 for ( nn = 0; nn < axis->width_count; nn++ ) 608 { 609 AF_Width width = axis->widths + nn; 610 611 612 width->cur = FT_MulFix( width->org, scale ); 613 width->fit = width->cur; 614 } 615 616 /* an extra-light axis corresponds to a standard width that is */ 617 /* smaller than 5/8 pixels */ 618 axis->extra_light = 619 (FT_Bool)( FT_MulFix( axis->standard_width, scale ) < 32 + 8 ); 620 621 if ( dim == AF_DIMENSION_VERT ) 622 { 623 /* scale the blue zones */ 624 for ( nn = 0; nn < axis->blue_count; nn++ ) 625 { 626 AF_LatinBlue blue = &axis->blues[nn]; 627 FT_Pos dist; 628 629 630 blue->ref.cur = FT_MulFix( blue->ref.org, scale ) + delta; 631 blue->ref.fit = blue->ref.cur; 632 blue->shoot.cur = FT_MulFix( blue->shoot.org, scale ) + delta; 633 blue->shoot.fit = blue->shoot.cur; 634 blue->flags &= ~AF_LATIN_BLUE_ACTIVE; 635 636 /* a blue zone is only active if it is less than 3/4 pixels tall */ 637 dist = FT_MulFix( blue->ref.org - blue->shoot.org, scale ); 638 if ( dist <= 48 && dist >= -48 ) 639 { 640 #if 0 641 FT_Pos delta1; 642 #endif 643 FT_Pos delta2; 644 645 646 /* use discrete values for blue zone widths */ 647 648 #if 0 649 650 /* generic, original code */ 651 delta1 = blue->shoot.org - blue->ref.org; 652 delta2 = delta1; 653 if ( delta1 < 0 ) 654 delta2 = -delta2; 655 656 delta2 = FT_MulFix( delta2, scale ); 657 658 if ( delta2 < 32 ) 659 delta2 = 0; 660 else if ( delta2 < 64 ) 661 delta2 = 32 + ( ( ( delta2 - 32 ) + 16 ) & ~31 ); 662 else 663 delta2 = FT_PIX_ROUND( delta2 ); 664 665 if ( delta1 < 0 ) 666 delta2 = -delta2; 667 668 blue->ref.fit = FT_PIX_ROUND( blue->ref.cur ); 669 blue->shoot.fit = blue->ref.fit + delta2; 670 671 #else 672 673 /* simplified version due to abs(dist) <= 48 */ 674 delta2 = dist; 675 if ( dist < 0 ) 676 delta2 = -delta2; 677 678 if ( delta2 < 32 ) 679 delta2 = 0; 680 else if ( delta < 48 ) 681 delta2 = 32; 682 else 683 delta2 = 64; 684 685 if ( dist < 0 ) 686 delta2 = -delta2; 687 688 blue->ref.fit = FT_PIX_ROUND( blue->ref.cur ); 689 blue->shoot.fit = blue->ref.fit - delta2; 690 691 #endif 692 693 blue->flags |= AF_LATIN_BLUE_ACTIVE; 694 } 695 } 696 } 697 } 698 699 700 /* Scale global values in both directions. */ 701 702 FT_LOCAL_DEF( void ) af_latin_metrics_scale(AF_LatinMetrics metrics,AF_Scaler scaler)703 af_latin_metrics_scale( AF_LatinMetrics metrics, 704 AF_Scaler scaler ) 705 { 706 metrics->root.scaler.render_mode = scaler->render_mode; 707 metrics->root.scaler.face = scaler->face; 708 709 af_latin_metrics_scale_dim( metrics, scaler, AF_DIMENSION_HORZ ); 710 af_latin_metrics_scale_dim( metrics, scaler, AF_DIMENSION_VERT ); 711 } 712 713 714 /*************************************************************************/ 715 /*************************************************************************/ 716 /***** *****/ 717 /***** L A T I N G L Y P H A N A L Y S I S *****/ 718 /***** *****/ 719 /*************************************************************************/ 720 /*************************************************************************/ 721 722 723 /* Walk over all contours and compute its segments. */ 724 725 FT_LOCAL_DEF( FT_Error ) af_latin_hints_compute_segments(AF_GlyphHints hints,AF_Dimension dim)726 af_latin_hints_compute_segments( AF_GlyphHints hints, 727 AF_Dimension dim ) 728 { 729 AF_AxisHints axis = &hints->axis[dim]; 730 FT_Memory memory = hints->memory; 731 FT_Error error = AF_Err_Ok; 732 AF_Segment segment = NULL; 733 AF_SegmentRec seg0; 734 AF_Point* contour = hints->contours; 735 AF_Point* contour_limit = contour + hints->num_contours; 736 AF_Direction major_dir, segment_dir; 737 738 739 FT_ZERO( &seg0 ); 740 seg0.score = 32000; 741 seg0.flags = AF_EDGE_NORMAL; 742 743 major_dir = (AF_Direction)FT_ABS( axis->major_dir ); 744 segment_dir = major_dir; 745 746 axis->num_segments = 0; 747 748 /* set up (u,v) in each point */ 749 if ( dim == AF_DIMENSION_HORZ ) 750 { 751 AF_Point point = hints->points; 752 AF_Point limit = point + hints->num_points; 753 754 755 for ( ; point < limit; point++ ) 756 { 757 point->u = point->fx; 758 point->v = point->fy; 759 } 760 } 761 else 762 { 763 AF_Point point = hints->points; 764 AF_Point limit = point + hints->num_points; 765 766 767 for ( ; point < limit; point++ ) 768 { 769 point->u = point->fy; 770 point->v = point->fx; 771 } 772 } 773 774 /* do each contour separately */ 775 for ( ; contour < contour_limit; contour++ ) 776 { 777 AF_Point point = contour[0]; 778 AF_Point last = point->prev; 779 int on_edge = 0; 780 FT_Pos min_pos = 32000; /* minimum segment pos != min_coord */ 781 FT_Pos max_pos = -32000; /* maximum segment pos != max_coord */ 782 FT_Bool passed; 783 784 785 if ( point == last ) /* skip singletons -- just in case */ 786 continue; 787 788 if ( FT_ABS( last->out_dir ) == major_dir && 789 FT_ABS( point->out_dir ) == major_dir ) 790 { 791 /* we are already on an edge, try to locate its start */ 792 last = point; 793 794 for (;;) 795 { 796 point = point->prev; 797 if ( FT_ABS( point->out_dir ) != major_dir ) 798 { 799 point = point->next; 800 break; 801 } 802 if ( point == last ) 803 break; 804 } 805 } 806 807 last = point; 808 passed = 0; 809 810 for (;;) 811 { 812 FT_Pos u, v; 813 814 815 if ( on_edge ) 816 { 817 u = point->u; 818 if ( u < min_pos ) 819 min_pos = u; 820 if ( u > max_pos ) 821 max_pos = u; 822 823 if ( point->out_dir != segment_dir || point == last ) 824 { 825 /* we are just leaving an edge; record a new segment! */ 826 segment->last = point; 827 segment->pos = (FT_Short)( ( min_pos + max_pos ) >> 1 ); 828 829 /* a segment is round if either its first or last point */ 830 /* is a control point */ 831 if ( ( segment->first->flags | point->flags ) & 832 AF_FLAG_CONTROL ) 833 segment->flags |= AF_EDGE_ROUND; 834 835 /* compute segment size */ 836 min_pos = max_pos = point->v; 837 838 v = segment->first->v; 839 if ( v < min_pos ) 840 min_pos = v; 841 if ( v > max_pos ) 842 max_pos = v; 843 844 segment->min_coord = (FT_Short)min_pos; 845 segment->max_coord = (FT_Short)max_pos; 846 segment->height = (FT_Short)( segment->max_coord - 847 segment->min_coord ); 848 849 on_edge = 0; 850 segment = NULL; 851 /* fallthrough */ 852 } 853 } 854 855 /* now exit if we are at the start/end point */ 856 if ( point == last ) 857 { 858 if ( passed ) 859 break; 860 passed = 1; 861 } 862 863 if ( !on_edge && FT_ABS( point->out_dir ) == major_dir ) 864 { 865 /* this is the start of a new segment! */ 866 segment_dir = (AF_Direction)point->out_dir; 867 868 /* clear all segment fields */ 869 error = af_axis_hints_new_segment( axis, memory, &segment ); 870 if ( error ) 871 goto Exit; 872 873 segment[0] = seg0; 874 segment->dir = (FT_Char)segment_dir; 875 min_pos = max_pos = point->u; 876 segment->first = point; 877 segment->last = point; 878 on_edge = 1; 879 } 880 881 point = point->next; 882 } 883 884 } /* contours */ 885 886 887 /* now slightly increase the height of segments when this makes */ 888 /* sense -- this is used to better detect and ignore serifs */ 889 { 890 AF_Segment segments = axis->segments; 891 AF_Segment segments_end = segments + axis->num_segments; 892 893 894 for ( segment = segments; segment < segments_end; segment++ ) 895 { 896 AF_Point first = segment->first; 897 AF_Point last = segment->last; 898 FT_Pos first_v = first->v; 899 FT_Pos last_v = last->v; 900 901 902 if ( first == last ) 903 continue; 904 905 if ( first_v < last_v ) 906 { 907 AF_Point p; 908 909 910 p = first->prev; 911 if ( p->v < first_v ) 912 segment->height = (FT_Short)( segment->height + 913 ( ( first_v - p->v ) >> 1 ) ); 914 915 p = last->next; 916 if ( p->v > last_v ) 917 segment->height = (FT_Short)( segment->height + 918 ( ( p->v - last_v ) >> 1 ) ); 919 } 920 else 921 { 922 AF_Point p; 923 924 925 p = first->prev; 926 if ( p->v > first_v ) 927 segment->height = (FT_Short)( segment->height + 928 ( ( p->v - first_v ) >> 1 ) ); 929 930 p = last->next; 931 if ( p->v < last_v ) 932 segment->height = (FT_Short)( segment->height + 933 ( ( last_v - p->v ) >> 1 ) ); 934 } 935 } 936 } 937 938 Exit: 939 return error; 940 } 941 942 943 /* Link segments to form stems and serifs. */ 944 945 FT_LOCAL_DEF( void ) af_latin_hints_link_segments(AF_GlyphHints hints,AF_Dimension dim)946 af_latin_hints_link_segments( AF_GlyphHints hints, 947 AF_Dimension dim ) 948 { 949 AF_AxisHints axis = &hints->axis[dim]; 950 AF_Segment segments = axis->segments; 951 AF_Segment segment_limit = segments + axis->num_segments; 952 FT_Pos len_threshold, len_score; 953 AF_Segment seg1, seg2; 954 955 956 len_threshold = AF_LATIN_CONSTANT( hints->metrics, 8 ); 957 if ( len_threshold == 0 ) 958 len_threshold = 1; 959 960 len_score = AF_LATIN_CONSTANT( hints->metrics, 6000 ); 961 962 /* now compare each segment to the others */ 963 for ( seg1 = segments; seg1 < segment_limit; seg1++ ) 964 { 965 /* the fake segments are introduced to hint the metrics -- */ 966 /* we must never link them to anything */ 967 if ( seg1->dir != axis->major_dir || seg1->first == seg1->last ) 968 continue; 969 970 /* search for stems having opposite directions, */ 971 /* with seg1 to the `left' of seg2 */ 972 for ( seg2 = segments; seg2 < segment_limit; seg2++ ) 973 { 974 FT_Pos pos1 = seg1->pos; 975 FT_Pos pos2 = seg2->pos; 976 977 978 if ( seg1->dir + seg2->dir == 0 && pos2 > pos1 ) 979 { 980 /* compute distance between the two segments */ 981 FT_Pos dist = pos2 - pos1; 982 FT_Pos min = seg1->min_coord; 983 FT_Pos max = seg1->max_coord; 984 FT_Pos len, score; 985 986 987 if ( min < seg2->min_coord ) 988 min = seg2->min_coord; 989 990 if ( max > seg2->max_coord ) 991 max = seg2->max_coord; 992 993 /* compute maximum coordinate difference of the two segments */ 994 len = max - min; 995 if ( len >= len_threshold ) 996 { 997 /* small coordinate differences cause a higher score, and */ 998 /* segments with a greater distance cause a higher score also */ 999 score = dist + len_score / len; 1000 1001 /* and we search for the smallest score */ 1002 /* of the sum of the two values */ 1003 if ( score < seg1->score ) 1004 { 1005 seg1->score = score; 1006 seg1->link = seg2; 1007 } 1008 1009 if ( score < seg2->score ) 1010 { 1011 seg2->score = score; 1012 seg2->link = seg1; 1013 } 1014 } 1015 } 1016 } 1017 } 1018 1019 /* now compute the `serif' segments, cf. explanations in `afhints.h' */ 1020 for ( seg1 = segments; seg1 < segment_limit; seg1++ ) 1021 { 1022 seg2 = seg1->link; 1023 1024 if ( seg2 ) 1025 { 1026 if ( seg2->link != seg1 ) 1027 { 1028 seg1->link = 0; 1029 seg1->serif = seg2->link; 1030 } 1031 } 1032 } 1033 } 1034 1035 1036 /* Link segments to edges, using feature analysis for selection. */ 1037 1038 FT_LOCAL_DEF( FT_Error ) af_latin_hints_compute_edges(AF_GlyphHints hints,AF_Dimension dim)1039 af_latin_hints_compute_edges( AF_GlyphHints hints, 1040 AF_Dimension dim ) 1041 { 1042 AF_AxisHints axis = &hints->axis[dim]; 1043 FT_Error error = AF_Err_Ok; 1044 FT_Memory memory = hints->memory; 1045 AF_LatinAxis laxis = &((AF_LatinMetrics)hints->metrics)->axis[dim]; 1046 1047 AF_Segment segments = axis->segments; 1048 AF_Segment segment_limit = segments + axis->num_segments; 1049 AF_Segment seg; 1050 1051 #if 0 1052 AF_Direction up_dir; 1053 #endif 1054 FT_Fixed scale; 1055 FT_Pos edge_distance_threshold; 1056 FT_Pos segment_length_threshold; 1057 1058 1059 axis->num_edges = 0; 1060 1061 scale = ( dim == AF_DIMENSION_HORZ ) ? hints->x_scale 1062 : hints->y_scale; 1063 1064 #if 0 1065 up_dir = ( dim == AF_DIMENSION_HORZ ) ? AF_DIR_UP 1066 : AF_DIR_RIGHT; 1067 #endif 1068 1069 /* 1070 * We ignore all segments that are less than 1 pixel in length 1071 * to avoid many problems with serif fonts. We compute the 1072 * corresponding threshold in font units. 1073 */ 1074 if ( dim == AF_DIMENSION_HORZ ) 1075 segment_length_threshold = FT_DivFix( 64, hints->y_scale ); 1076 else 1077 segment_length_threshold = 0; 1078 1079 /*********************************************************************/ 1080 /* */ 1081 /* We begin by generating a sorted table of edges for the current */ 1082 /* direction. To do so, we simply scan each segment and try to find */ 1083 /* an edge in our table that corresponds to its position. */ 1084 /* */ 1085 /* If no edge is found, we create and insert a new edge in the */ 1086 /* sorted table. Otherwise, we simply add the segment to the edge's */ 1087 /* list which gets processed in the second step to compute the */ 1088 /* edge's properties. */ 1089 /* */ 1090 /* Note that the table of edges is sorted along the segment/edge */ 1091 /* position. */ 1092 /* */ 1093 /*********************************************************************/ 1094 1095 /* assure that edge distance threshold is at most 0.25px */ 1096 edge_distance_threshold = FT_MulFix( laxis->edge_distance_threshold, 1097 scale ); 1098 if ( edge_distance_threshold > 64 / 4 ) 1099 edge_distance_threshold = 64 / 4; 1100 1101 edge_distance_threshold = FT_DivFix( edge_distance_threshold, 1102 scale ); 1103 1104 for ( seg = segments; seg < segment_limit; seg++ ) 1105 { 1106 AF_Edge found = NULL; 1107 FT_Int ee; 1108 1109 1110 if ( seg->height < segment_length_threshold ) 1111 continue; 1112 1113 /* A special case for serif edges: If they are smaller than */ 1114 /* 1.5 pixels we ignore them. */ 1115 if ( seg->serif && 1116 2 * seg->height < 3 * segment_length_threshold ) 1117 continue; 1118 1119 /* look for an edge corresponding to the segment */ 1120 for ( ee = 0; ee < axis->num_edges; ee++ ) 1121 { 1122 AF_Edge edge = axis->edges + ee; 1123 FT_Pos dist; 1124 1125 1126 dist = seg->pos - edge->fpos; 1127 if ( dist < 0 ) 1128 dist = -dist; 1129 1130 if ( dist < edge_distance_threshold && edge->dir == seg->dir ) 1131 { 1132 found = edge; 1133 break; 1134 } 1135 } 1136 1137 if ( !found ) 1138 { 1139 AF_Edge edge; 1140 1141 1142 /* insert a new edge in the list and */ 1143 /* sort according to the position */ 1144 error = af_axis_hints_new_edge( axis, seg->pos, 1145 (AF_Direction)seg->dir, 1146 memory, &edge ); 1147 if ( error ) 1148 goto Exit; 1149 1150 /* add the segment to the new edge's list */ 1151 FT_ZERO( edge ); 1152 1153 edge->first = seg; 1154 edge->last = seg; 1155 edge->dir = seg->dir; 1156 edge->fpos = seg->pos; 1157 edge->opos = FT_MulFix( seg->pos, scale ); 1158 edge->pos = edge->opos; 1159 seg->edge_next = seg; 1160 } 1161 else 1162 { 1163 /* if an edge was found, simply add the segment to the edge's */ 1164 /* list */ 1165 seg->edge_next = found->first; 1166 found->last->edge_next = seg; 1167 found->last = seg; 1168 } 1169 } 1170 1171 1172 /*********************************************************************/ 1173 /* */ 1174 /* Good, we will now compute each edge's properties according to */ 1175 /* the segments found on its position. Basically, these are */ 1176 /* */ 1177 /* - the edge's main direction */ 1178 /* - stem edge, serif edge or both (which defaults to stem then) */ 1179 /* - rounded edge, straight or both (which defaults to straight) */ 1180 /* - link for edge */ 1181 /* */ 1182 /*********************************************************************/ 1183 1184 /* first of all, set the `edge' field in each segment -- this is */ 1185 /* required in order to compute edge links */ 1186 1187 /* 1188 * Note that removing this loop and setting the `edge' field of each 1189 * segment directly in the code above slows down execution speed for 1190 * some reasons on platforms like the Sun. 1191 */ 1192 { 1193 AF_Edge edges = axis->edges; 1194 AF_Edge edge_limit = edges + axis->num_edges; 1195 AF_Edge edge; 1196 1197 1198 for ( edge = edges; edge < edge_limit; edge++ ) 1199 { 1200 seg = edge->first; 1201 if ( seg ) 1202 do 1203 { 1204 seg->edge = edge; 1205 seg = seg->edge_next; 1206 1207 } while ( seg != edge->first ); 1208 } 1209 1210 /* now compute each edge properties */ 1211 for ( edge = edges; edge < edge_limit; edge++ ) 1212 { 1213 FT_Int is_round = 0; /* does it contain round segments? */ 1214 FT_Int is_straight = 0; /* does it contain straight segments? */ 1215 #if 0 1216 FT_Pos ups = 0; /* number of upwards segments */ 1217 FT_Pos downs = 0; /* number of downwards segments */ 1218 #endif 1219 1220 1221 seg = edge->first; 1222 1223 do 1224 { 1225 FT_Bool is_serif; 1226 1227 1228 /* check for roundness of segment */ 1229 if ( seg->flags & AF_EDGE_ROUND ) 1230 is_round++; 1231 else 1232 is_straight++; 1233 1234 #if 0 1235 /* check for segment direction */ 1236 if ( seg->dir == up_dir ) 1237 ups += seg->max_coord - seg->min_coord; 1238 else 1239 downs += seg->max_coord - seg->min_coord; 1240 #endif 1241 1242 /* check for links -- if seg->serif is set, then seg->link must */ 1243 /* be ignored */ 1244 is_serif = (FT_Bool)( seg->serif && 1245 seg->serif->edge && 1246 seg->serif->edge != edge ); 1247 1248 if ( ( seg->link && seg->link->edge != NULL ) || is_serif ) 1249 { 1250 AF_Edge edge2; 1251 AF_Segment seg2; 1252 1253 1254 edge2 = edge->link; 1255 seg2 = seg->link; 1256 1257 if ( is_serif ) 1258 { 1259 seg2 = seg->serif; 1260 edge2 = edge->serif; 1261 } 1262 1263 if ( edge2 ) 1264 { 1265 FT_Pos edge_delta; 1266 FT_Pos seg_delta; 1267 1268 1269 edge_delta = edge->fpos - edge2->fpos; 1270 if ( edge_delta < 0 ) 1271 edge_delta = -edge_delta; 1272 1273 seg_delta = seg->pos - seg2->pos; 1274 if ( seg_delta < 0 ) 1275 seg_delta = -seg_delta; 1276 1277 if ( seg_delta < edge_delta ) 1278 edge2 = seg2->edge; 1279 } 1280 else 1281 edge2 = seg2->edge; 1282 1283 if ( is_serif ) 1284 { 1285 edge->serif = edge2; 1286 edge2->flags |= AF_EDGE_SERIF; 1287 } 1288 else 1289 edge->link = edge2; 1290 } 1291 1292 seg = seg->edge_next; 1293 1294 } while ( seg != edge->first ); 1295 1296 /* set the round/straight flags */ 1297 edge->flags = AF_EDGE_NORMAL; 1298 1299 if ( is_round > 0 && is_round >= is_straight ) 1300 edge->flags |= AF_EDGE_ROUND; 1301 1302 #if 0 1303 /* set the edge's main direction */ 1304 edge->dir = AF_DIR_NONE; 1305 1306 if ( ups > downs ) 1307 edge->dir = (FT_Char)up_dir; 1308 1309 else if ( ups < downs ) 1310 edge->dir = (FT_Char)-up_dir; 1311 1312 else if ( ups == downs ) 1313 edge->dir = 0; /* both up and down! */ 1314 #endif 1315 1316 /* get rid of serifs if link is set */ 1317 /* XXX: This gets rid of many unpleasant artefacts! */ 1318 /* Example: the `c' in cour.pfa at size 13 */ 1319 1320 if ( edge->serif && edge->link ) 1321 edge->serif = 0; 1322 } 1323 } 1324 1325 Exit: 1326 return error; 1327 } 1328 1329 1330 /* Detect segments and edges for given dimension. */ 1331 1332 FT_LOCAL_DEF( FT_Error ) af_latin_hints_detect_features(AF_GlyphHints hints,AF_Dimension dim)1333 af_latin_hints_detect_features( AF_GlyphHints hints, 1334 AF_Dimension dim ) 1335 { 1336 FT_Error error; 1337 1338 1339 error = af_latin_hints_compute_segments( hints, dim ); 1340 if ( !error ) 1341 { 1342 af_latin_hints_link_segments( hints, dim ); 1343 1344 error = af_latin_hints_compute_edges( hints, dim ); 1345 } 1346 1347 return error; 1348 } 1349 1350 1351 /* Compute all edges which lie within blue zones. */ 1352 1353 FT_LOCAL_DEF( void ) af_latin_hints_compute_blue_edges(AF_GlyphHints hints,AF_LatinMetrics metrics)1354 af_latin_hints_compute_blue_edges( AF_GlyphHints hints, 1355 AF_LatinMetrics metrics ) 1356 { 1357 AF_AxisHints axis = &hints->axis[AF_DIMENSION_VERT]; 1358 AF_Edge edge = axis->edges; 1359 AF_Edge edge_limit = edge + axis->num_edges; 1360 AF_LatinAxis latin = &metrics->axis[AF_DIMENSION_VERT]; 1361 FT_Fixed scale = latin->scale; 1362 1363 1364 /* compute which blue zones are active, i.e. have their scaled */ 1365 /* size < 3/4 pixels */ 1366 1367 /* for each horizontal edge search the blue zone which is closest */ 1368 for ( ; edge < edge_limit; edge++ ) 1369 { 1370 FT_Int bb; 1371 AF_Width best_blue = NULL; 1372 FT_Pos best_dist; /* initial threshold */ 1373 1374 1375 /* compute the initial threshold as a fraction of the EM size */ 1376 /* (the value 40 is heuristic) */ 1377 best_dist = FT_MulFix( metrics->units_per_em / 40, scale ); 1378 1379 /* assure a minimum distance of 0.5px */ 1380 if ( best_dist > 64 / 2 ) 1381 best_dist = 64 / 2; 1382 1383 for ( bb = 0; bb < AF_LATIN_BLUE_MAX; bb++ ) 1384 { 1385 AF_LatinBlue blue = latin->blues + bb; 1386 FT_Bool is_top_blue, is_major_dir; 1387 1388 1389 /* skip inactive blue zones (i.e., those that are too large) */ 1390 if ( !( blue->flags & AF_LATIN_BLUE_ACTIVE ) ) 1391 continue; 1392 1393 /* if it is a top zone, check for right edges -- if it is a bottom */ 1394 /* zone, check for left edges */ 1395 /* */ 1396 /* of course, that's for TrueType */ 1397 is_top_blue = (FT_Byte)( ( blue->flags & AF_LATIN_BLUE_TOP ) != 0 ); 1398 is_major_dir = FT_BOOL( edge->dir == axis->major_dir ); 1399 1400 /* if it is a top zone, the edge must be against the major */ 1401 /* direction; if it is a bottom zone, it must be in the major */ 1402 /* direction */ 1403 if ( is_top_blue ^ is_major_dir ) 1404 { 1405 FT_Pos dist; 1406 1407 1408 /* first of all, compare it to the reference position */ 1409 dist = edge->fpos - blue->ref.org; 1410 if ( dist < 0 ) 1411 dist = -dist; 1412 1413 dist = FT_MulFix( dist, scale ); 1414 if ( dist < best_dist ) 1415 { 1416 best_dist = dist; 1417 best_blue = &blue->ref; 1418 } 1419 1420 /* now compare it to the overshoot position and check whether */ 1421 /* the edge is rounded, and whether the edge is over the */ 1422 /* reference position of a top zone, or under the reference */ 1423 /* position of a bottom zone */ 1424 if ( edge->flags & AF_EDGE_ROUND && dist != 0 ) 1425 { 1426 FT_Bool is_under_ref = FT_BOOL( edge->fpos < blue->ref.org ); 1427 1428 1429 if ( is_top_blue ^ is_under_ref ) 1430 { 1431 dist = edge->fpos - blue->shoot.org; 1432 if ( dist < 0 ) 1433 dist = -dist; 1434 1435 dist = FT_MulFix( dist, scale ); 1436 if ( dist < best_dist ) 1437 { 1438 best_dist = dist; 1439 best_blue = &blue->shoot; 1440 } 1441 } 1442 } 1443 } 1444 } 1445 1446 if ( best_blue ) 1447 edge->blue_edge = best_blue; 1448 } 1449 } 1450 1451 1452 /* Initalize hinting engine. */ 1453 1454 static FT_Error af_latin_hints_init(AF_GlyphHints hints,AF_LatinMetrics metrics)1455 af_latin_hints_init( AF_GlyphHints hints, 1456 AF_LatinMetrics metrics ) 1457 { 1458 FT_Render_Mode mode; 1459 FT_UInt32 scaler_flags, other_flags; 1460 FT_Face face = metrics->root.scaler.face; 1461 1462 1463 af_glyph_hints_rescale( hints, (AF_ScriptMetrics)metrics ); 1464 1465 /* 1466 * correct x_scale and y_scale if needed, since they may have 1467 * been modified by `af_latin_metrics_scale_dim' above 1468 */ 1469 hints->x_scale = metrics->axis[AF_DIMENSION_HORZ].scale; 1470 hints->x_delta = metrics->axis[AF_DIMENSION_HORZ].delta; 1471 hints->y_scale = metrics->axis[AF_DIMENSION_VERT].scale; 1472 hints->y_delta = metrics->axis[AF_DIMENSION_VERT].delta; 1473 1474 /* compute flags depending on render mode, etc. */ 1475 mode = metrics->root.scaler.render_mode; 1476 1477 #if 0 /* #ifdef AF_CONFIG_OPTION_USE_WARPER */ 1478 if ( mode == FT_RENDER_MODE_LCD || mode == FT_RENDER_MODE_LCD_V ) 1479 { 1480 metrics->root.scaler.render_mode = mode = FT_RENDER_MODE_NORMAL; 1481 } 1482 #endif 1483 1484 scaler_flags = hints->scaler_flags; 1485 other_flags = 0; 1486 1487 /* 1488 * We snap the width of vertical stems for the monochrome and 1489 * horizontal LCD rendering targets only. 1490 */ 1491 if ( mode == FT_RENDER_MODE_MONO || mode == FT_RENDER_MODE_LCD ) 1492 other_flags |= AF_LATIN_HINTS_HORZ_SNAP; 1493 1494 /* 1495 * We snap the width of horizontal stems for the monochrome and 1496 * vertical LCD rendering targets only. 1497 */ 1498 if ( mode == FT_RENDER_MODE_MONO || mode == FT_RENDER_MODE_LCD_V ) 1499 other_flags |= AF_LATIN_HINTS_VERT_SNAP; 1500 1501 /* 1502 * We adjust stems to full pixels only if we don't use the `light' mode. 1503 */ 1504 if ( mode != FT_RENDER_MODE_LIGHT ) 1505 other_flags |= AF_LATIN_HINTS_STEM_ADJUST; 1506 1507 if ( mode == FT_RENDER_MODE_MONO ) 1508 other_flags |= AF_LATIN_HINTS_MONO; 1509 1510 /* 1511 * In `light' hinting mode we disable horizontal hinting completely. 1512 * We also do it if the face is italic. 1513 */ 1514 if ( mode == FT_RENDER_MODE_LIGHT || 1515 ( face->style_flags & FT_STYLE_FLAG_ITALIC ) != 0 ) 1516 scaler_flags |= AF_SCALER_FLAG_NO_HORIZONTAL; 1517 1518 hints->scaler_flags = scaler_flags; 1519 hints->other_flags = other_flags; 1520 1521 return AF_Err_Ok; 1522 } 1523 1524 1525 /*************************************************************************/ 1526 /*************************************************************************/ 1527 /***** *****/ 1528 /***** L A T I N G L Y P H G R I D - F I T T I N G *****/ 1529 /***** *****/ 1530 /*************************************************************************/ 1531 /*************************************************************************/ 1532 1533 /* Snap a given width in scaled coordinates to one of the */ 1534 /* current standard widths. */ 1535 1536 static FT_Pos af_latin_snap_width(AF_Width widths,FT_Int count,FT_Pos width)1537 af_latin_snap_width( AF_Width widths, 1538 FT_Int count, 1539 FT_Pos width ) 1540 { 1541 int n; 1542 FT_Pos best = 64 + 32 + 2; 1543 FT_Pos reference = width; 1544 FT_Pos scaled; 1545 1546 1547 for ( n = 0; n < count; n++ ) 1548 { 1549 FT_Pos w; 1550 FT_Pos dist; 1551 1552 1553 w = widths[n].cur; 1554 dist = width - w; 1555 if ( dist < 0 ) 1556 dist = -dist; 1557 if ( dist < best ) 1558 { 1559 best = dist; 1560 reference = w; 1561 } 1562 } 1563 1564 scaled = FT_PIX_ROUND( reference ); 1565 1566 if ( width >= reference ) 1567 { 1568 if ( width < scaled + 48 ) 1569 width = reference; 1570 } 1571 else 1572 { 1573 if ( width > scaled - 48 ) 1574 width = reference; 1575 } 1576 1577 return width; 1578 } 1579 1580 1581 /* Compute the snapped width of a given stem, ignoring very thin ones. */ 1582 /* There is a lot of voodoo in this function; changing the hard-coded */ 1583 /* parameters influence the whole hinting process. */ 1584 1585 static FT_Pos af_latin_compute_stem_width(AF_GlyphHints hints,AF_Dimension dim,FT_Pos width,AF_Edge_Flags base_flags,AF_Edge_Flags stem_flags)1586 af_latin_compute_stem_width( AF_GlyphHints hints, 1587 AF_Dimension dim, 1588 FT_Pos width, 1589 AF_Edge_Flags base_flags, 1590 AF_Edge_Flags stem_flags ) 1591 { 1592 AF_LatinMetrics metrics = (AF_LatinMetrics) hints->metrics; 1593 AF_LatinAxis axis = & metrics->axis[dim]; 1594 FT_Pos dist = width; 1595 FT_Int sign = 0; 1596 FT_Int vertical = ( dim == AF_DIMENSION_VERT ); 1597 1598 1599 if ( !AF_LATIN_HINTS_DO_STEM_ADJUST( hints ) || 1600 axis->extra_light ) 1601 return width; 1602 1603 if ( dist < 0 ) 1604 { 1605 dist = -width; 1606 sign = 1; 1607 } 1608 1609 if ( ( vertical && !AF_LATIN_HINTS_DO_VERT_SNAP( hints ) ) || 1610 ( !vertical && !AF_LATIN_HINTS_DO_HORZ_SNAP( hints ) ) ) 1611 { 1612 /* smooth hinting process: very lightly quantize the stem width */ 1613 1614 /* leave the widths of serifs alone */ 1615 if ( ( stem_flags & AF_EDGE_SERIF ) && 1616 vertical && 1617 ( dist < 3 * 64 ) ) 1618 goto Done_Width; 1619 1620 else if ( base_flags & AF_EDGE_ROUND ) 1621 { 1622 if ( dist < 80 ) 1623 dist = 64; 1624 } 1625 else if ( dist < 56 ) 1626 dist = 56; 1627 1628 if ( axis->width_count > 0 ) 1629 { 1630 FT_Pos delta; 1631 1632 1633 /* compare to standard width */ 1634 delta = dist - axis->widths[0].cur; 1635 1636 if ( delta < 0 ) 1637 delta = -delta; 1638 1639 if ( delta < 40 ) 1640 { 1641 dist = axis->widths[0].cur; 1642 if ( dist < 48 ) 1643 dist = 48; 1644 1645 goto Done_Width; 1646 } 1647 1648 if ( dist < 3 * 64 ) 1649 { 1650 delta = dist & 63; 1651 dist &= -64; 1652 1653 if ( delta < 10 ) 1654 dist += delta; 1655 1656 else if ( delta < 32 ) 1657 dist += 10; 1658 1659 else if ( delta < 54 ) 1660 dist += 54; 1661 1662 else 1663 dist += delta; 1664 } 1665 else 1666 dist = ( dist + 32 ) & ~63; 1667 } 1668 } 1669 else 1670 { 1671 /* strong hinting process: snap the stem width to integer pixels */ 1672 1673 FT_Pos org_dist = dist; 1674 1675 1676 dist = af_latin_snap_width( axis->widths, axis->width_count, dist ); 1677 1678 if ( vertical ) 1679 { 1680 /* in the case of vertical hinting, always round */ 1681 /* the stem heights to integer pixels */ 1682 1683 if ( dist >= 64 ) 1684 dist = ( dist + 16 ) & ~63; 1685 else 1686 dist = 64; 1687 } 1688 else 1689 { 1690 if ( AF_LATIN_HINTS_DO_MONO( hints ) ) 1691 { 1692 /* monochrome horizontal hinting: snap widths to integer pixels */ 1693 /* with a different threshold */ 1694 1695 if ( dist < 64 ) 1696 dist = 64; 1697 else 1698 dist = ( dist + 32 ) & ~63; 1699 } 1700 else 1701 { 1702 /* for horizontal anti-aliased hinting, we adopt a more subtle */ 1703 /* approach: we strengthen small stems, round stems whose size */ 1704 /* is between 1 and 2 pixels to an integer, otherwise nothing */ 1705 1706 if ( dist < 48 ) 1707 dist = ( dist + 64 ) >> 1; 1708 1709 else if ( dist < 128 ) 1710 { 1711 /* We only round to an integer width if the corresponding */ 1712 /* distortion is less than 1/4 pixel. Otherwise this */ 1713 /* makes everything worse since the diagonals, which are */ 1714 /* not hinted, appear a lot bolder or thinner than the */ 1715 /* vertical stems. */ 1716 1717 FT_Pos delta; 1718 1719 1720 dist = ( dist + 22 ) & ~63; 1721 delta = dist - org_dist; 1722 if ( delta < 0 ) 1723 delta = -delta; 1724 1725 if (delta >= 16) 1726 { 1727 dist = org_dist; 1728 if ( dist < 48 ) 1729 dist = ( dist + 64 ) >> 1; 1730 } 1731 } 1732 else 1733 /* round otherwise to prevent color fringes in LCD mode */ 1734 dist = ( dist + 32 ) & ~63; 1735 } 1736 } 1737 } 1738 1739 Done_Width: 1740 if ( sign ) 1741 dist = -dist; 1742 1743 return dist; 1744 } 1745 1746 1747 /* Align one stem edge relative to the previous stem edge. */ 1748 1749 static void af_latin_align_linked_edge(AF_GlyphHints hints,AF_Dimension dim,AF_Edge base_edge,AF_Edge stem_edge)1750 af_latin_align_linked_edge( AF_GlyphHints hints, 1751 AF_Dimension dim, 1752 AF_Edge base_edge, 1753 AF_Edge stem_edge ) 1754 { 1755 FT_Pos dist = stem_edge->opos - base_edge->opos; 1756 1757 FT_Pos fitted_width = af_latin_compute_stem_width( 1758 hints, dim, dist, 1759 (AF_Edge_Flags)base_edge->flags, 1760 (AF_Edge_Flags)stem_edge->flags ); 1761 1762 1763 stem_edge->pos = base_edge->pos + fitted_width; 1764 1765 FT_TRACE5(( " LINK: edge %d (opos=%.2f) linked to (%.2f)," 1766 " dist was %.2f, now %.2f\n", 1767 stem_edge-hints->axis[dim].edges, stem_edge->opos / 64.0, 1768 stem_edge->pos / 64.0, dist / 64.0, fitted_width / 64.0 )); 1769 } 1770 1771 1772 /* Shift the coordinates of the `serif' edge by the same amount */ 1773 /* as the corresponding `base' edge has been moved already. */ 1774 1775 static void af_latin_align_serif_edge(AF_GlyphHints hints,AF_Edge base,AF_Edge serif)1776 af_latin_align_serif_edge( AF_GlyphHints hints, 1777 AF_Edge base, 1778 AF_Edge serif ) 1779 { 1780 FT_UNUSED( hints ); 1781 1782 serif->pos = base->pos + ( serif->opos - base->opos ); 1783 } 1784 1785 1786 /*************************************************************************/ 1787 /*************************************************************************/ 1788 /*************************************************************************/ 1789 /**** ****/ 1790 /**** E D G E H I N T I N G ****/ 1791 /**** ****/ 1792 /*************************************************************************/ 1793 /*************************************************************************/ 1794 /*************************************************************************/ 1795 1796 1797 /* The main grid-fitting routine. */ 1798 1799 FT_LOCAL_DEF( void ) af_latin_hint_edges(AF_GlyphHints hints,AF_Dimension dim)1800 af_latin_hint_edges( AF_GlyphHints hints, 1801 AF_Dimension dim ) 1802 { 1803 AF_AxisHints axis = &hints->axis[dim]; 1804 AF_Edge edges = axis->edges; 1805 AF_Edge edge_limit = edges + axis->num_edges; 1806 FT_PtrDist n_edges; 1807 AF_Edge edge; 1808 AF_Edge anchor = NULL; 1809 FT_Int has_serifs = 0; 1810 1811 1812 FT_TRACE5(("%s edge hinting\n", dim == AF_DIMENSION_VERT ? "horizontal" 1813 : "vertical")); 1814 1815 /* we begin by aligning all stems relative to the blue zone */ 1816 /* if needed -- that's only for horizontal edges */ 1817 1818 if ( dim == AF_DIMENSION_VERT && AF_HINTS_DO_BLUES( hints ) ) 1819 { 1820 for ( edge = edges; edge < edge_limit; edge++ ) 1821 { 1822 AF_Width blue; 1823 AF_Edge edge1, edge2; /* these edges form the stem to check */ 1824 1825 1826 if ( edge->flags & AF_EDGE_DONE ) 1827 continue; 1828 1829 blue = edge->blue_edge; 1830 edge1 = NULL; 1831 edge2 = edge->link; 1832 1833 if ( blue ) 1834 edge1 = edge; 1835 1836 /* flip edges if the other stem is aligned to a blue zone */ 1837 else if ( edge2 && edge2->blue_edge ) 1838 { 1839 blue = edge2->blue_edge; 1840 edge1 = edge2; 1841 edge2 = edge; 1842 } 1843 1844 if ( !edge1 ) 1845 continue; 1846 1847 FT_TRACE5(( " BLUE: edge %d (opos=%.2f) snapped to (%.2f)," 1848 " was (%.2f)\n", 1849 edge1 - edges, edge1->opos / 64.0, blue->fit / 64.0, 1850 edge1->pos / 64.0 )); 1851 1852 edge1->pos = blue->fit; 1853 edge1->flags |= AF_EDGE_DONE; 1854 1855 if ( edge2 && !edge2->blue_edge ) 1856 { 1857 af_latin_align_linked_edge( hints, dim, edge1, edge2 ); 1858 edge2->flags |= AF_EDGE_DONE; 1859 } 1860 1861 if ( !anchor ) 1862 anchor = edge; 1863 } 1864 } 1865 1866 /* now we align all other stem edges, trying to maintain the */ 1867 /* relative order of stems in the glyph */ 1868 for ( edge = edges; edge < edge_limit; edge++ ) 1869 { 1870 AF_Edge edge2; 1871 1872 1873 if ( edge->flags & AF_EDGE_DONE ) 1874 continue; 1875 1876 /* skip all non-stem edges */ 1877 edge2 = edge->link; 1878 if ( !edge2 ) 1879 { 1880 has_serifs++; 1881 continue; 1882 } 1883 1884 /* now align the stem */ 1885 1886 /* this should not happen, but it's better to be safe */ 1887 if ( edge2->blue_edge ) 1888 { 1889 FT_TRACE5(( " ASSERTION FAILED for edge %d\n", edge2-edges )); 1890 1891 af_latin_align_linked_edge( hints, dim, edge2, edge ); 1892 edge->flags |= AF_EDGE_DONE; 1893 continue; 1894 } 1895 1896 if ( !anchor ) 1897 { 1898 /* if we reach this if clause, no stem has been aligned yet */ 1899 1900 FT_Pos org_len, org_center, cur_len; 1901 FT_Pos cur_pos1, error1, error2, u_off, d_off; 1902 1903 1904 org_len = edge2->opos - edge->opos; 1905 cur_len = af_latin_compute_stem_width( 1906 hints, dim, org_len, 1907 (AF_Edge_Flags)edge->flags, 1908 (AF_Edge_Flags)edge2->flags ); 1909 1910 /* some voodoo to specially round edges for small stem widths; */ 1911 /* the idea is to align the center of a stem, then shifting */ 1912 /* the stem edges to suitable positions */ 1913 if ( cur_len <= 64 ) 1914 { 1915 /* width <= 1px */ 1916 u_off = 32; 1917 d_off = 32; 1918 } 1919 else 1920 { 1921 /* 1px < width < 1.5px */ 1922 u_off = 38; 1923 d_off = 26; 1924 } 1925 1926 if ( cur_len < 96 ) 1927 { 1928 org_center = edge->opos + ( org_len >> 1 ); 1929 cur_pos1 = FT_PIX_ROUND( org_center ); 1930 1931 error1 = org_center - ( cur_pos1 - u_off ); 1932 if ( error1 < 0 ) 1933 error1 = -error1; 1934 1935 error2 = org_center - ( cur_pos1 + d_off ); 1936 if ( error2 < 0 ) 1937 error2 = -error2; 1938 1939 if ( error1 < error2 ) 1940 cur_pos1 -= u_off; 1941 else 1942 cur_pos1 += d_off; 1943 1944 edge->pos = cur_pos1 - cur_len / 2; 1945 edge2->pos = edge->pos + cur_len; 1946 } 1947 else 1948 edge->pos = FT_PIX_ROUND( edge->opos ); 1949 1950 FT_TRACE5(( " ANCHOR: edge %d (opos=%.2f) and %d (opos=%.2f)" 1951 " snapped to (%.2f) (%.2f)\n", 1952 edge - edges, edge->opos / 64.0, 1953 edge2 - edges, edge2->opos / 64.0, 1954 edge->pos / 64.0, edge2->pos / 64.0 )); 1955 anchor = edge; 1956 1957 edge->flags |= AF_EDGE_DONE; 1958 1959 af_latin_align_linked_edge( hints, dim, edge, edge2 ); 1960 } 1961 else 1962 { 1963 FT_Pos org_pos, org_len, org_center, cur_len; 1964 FT_Pos cur_pos1, cur_pos2, delta1, delta2; 1965 1966 1967 org_pos = anchor->pos + ( edge->opos - anchor->opos ); 1968 org_len = edge2->opos - edge->opos; 1969 org_center = org_pos + ( org_len >> 1 ); 1970 1971 cur_len = af_latin_compute_stem_width( 1972 hints, dim, org_len, 1973 (AF_Edge_Flags)edge->flags, 1974 (AF_Edge_Flags)edge2->flags ); 1975 1976 if ( edge2->flags & AF_EDGE_DONE ) 1977 { 1978 FT_TRACE5(( " ADJUST: edge %d (pos=%.2f) moved to %.2f\n", 1979 edge - edges, edge->pos / 64.0, 1980 ( edge2->pos - cur_len ) / 64.0 )); 1981 1982 edge->pos = edge2->pos - cur_len; 1983 } 1984 1985 else if ( cur_len < 96 ) 1986 { 1987 FT_Pos u_off, d_off; 1988 1989 1990 cur_pos1 = FT_PIX_ROUND( org_center ); 1991 1992 if (cur_len <= 64 ) 1993 { 1994 u_off = 32; 1995 d_off = 32; 1996 } 1997 else 1998 { 1999 u_off = 38; 2000 d_off = 26; 2001 } 2002 2003 delta1 = org_center - ( cur_pos1 - u_off ); 2004 if ( delta1 < 0 ) 2005 delta1 = -delta1; 2006 2007 delta2 = org_center - ( cur_pos1 + d_off ); 2008 if ( delta2 < 0 ) 2009 delta2 = -delta2; 2010 2011 if ( delta1 < delta2 ) 2012 cur_pos1 -= u_off; 2013 else 2014 cur_pos1 += d_off; 2015 2016 edge->pos = cur_pos1 - cur_len / 2; 2017 edge2->pos = cur_pos1 + cur_len / 2; 2018 2019 FT_TRACE5(( " STEM: %d (opos=%.2f) to %d (opos=%.2f)" 2020 " snapped to (%.2f) and (%.2f)\n", 2021 edge - edges, edge->opos / 64.0, 2022 edge2 - edges, edge2->opos / 64.0, 2023 edge->pos / 64.0, edge2->pos / 64.0 )); 2024 } 2025 else 2026 { 2027 org_pos = anchor->pos + ( edge->opos - anchor->opos ); 2028 org_len = edge2->opos - edge->opos; 2029 org_center = org_pos + ( org_len >> 1 ); 2030 2031 cur_len = af_latin_compute_stem_width( 2032 hints, dim, org_len, 2033 (AF_Edge_Flags)edge->flags, 2034 (AF_Edge_Flags)edge2->flags ); 2035 2036 cur_pos1 = FT_PIX_ROUND( org_pos ); 2037 delta1 = cur_pos1 + ( cur_len >> 1 ) - org_center; 2038 if ( delta1 < 0 ) 2039 delta1 = -delta1; 2040 2041 cur_pos2 = FT_PIX_ROUND( org_pos + org_len ) - cur_len; 2042 delta2 = cur_pos2 + ( cur_len >> 1 ) - org_center; 2043 if ( delta2 < 0 ) 2044 delta2 = -delta2; 2045 2046 edge->pos = ( delta1 < delta2 ) ? cur_pos1 : cur_pos2; 2047 edge2->pos = edge->pos + cur_len; 2048 2049 FT_TRACE5(( " STEM: %d (opos=%.2f) to %d (opos=%.2f)" 2050 " snapped to (%.2f) and (%.2f)\n", 2051 edge - edges, edge->opos / 64.0, 2052 edge2 - edges, edge2->opos / 64.0, 2053 edge->pos / 64.0, edge2->pos / 64.0 )); 2054 } 2055 2056 edge->flags |= AF_EDGE_DONE; 2057 edge2->flags |= AF_EDGE_DONE; 2058 2059 if ( edge > edges && edge->pos < edge[-1].pos ) 2060 { 2061 FT_TRACE5(( " BOUND: %d (pos=%.2f) to (%.2f)\n", 2062 edge - edges, edge->pos / 64.0, edge[-1].pos / 64.0 )); 2063 edge->pos = edge[-1].pos; 2064 } 2065 } 2066 } 2067 2068 /* make sure that lowercase m's maintain their symmetry */ 2069 2070 /* In general, lowercase m's have six vertical edges if they are sans */ 2071 /* serif, or twelve if they are with serifs. This implementation is */ 2072 /* based on that assumption, and seems to work very well with most */ 2073 /* faces. However, if for a certain face this assumption is not */ 2074 /* true, the m is just rendered like before. In addition, any stem */ 2075 /* correction will only be applied to symmetrical glyphs (even if the */ 2076 /* glyph is not an m), so the potential for unwanted distortion is */ 2077 /* relatively low. */ 2078 2079 /* We don't handle horizontal edges since we can't easily assure that */ 2080 /* the third (lowest) stem aligns with the base line; it might end up */ 2081 /* one pixel higher or lower. */ 2082 2083 n_edges = edge_limit - edges; 2084 if ( dim == AF_DIMENSION_HORZ && ( n_edges == 6 || n_edges == 12 ) ) 2085 { 2086 AF_Edge edge1, edge2, edge3; 2087 FT_Pos dist1, dist2, span, delta; 2088 2089 2090 if ( n_edges == 6 ) 2091 { 2092 edge1 = edges; 2093 edge2 = edges + 2; 2094 edge3 = edges + 4; 2095 } 2096 else 2097 { 2098 edge1 = edges + 1; 2099 edge2 = edges + 5; 2100 edge3 = edges + 9; 2101 } 2102 2103 dist1 = edge2->opos - edge1->opos; 2104 dist2 = edge3->opos - edge2->opos; 2105 2106 span = dist1 - dist2; 2107 if ( span < 0 ) 2108 span = -span; 2109 2110 if ( span < 8 ) 2111 { 2112 delta = edge3->pos - ( 2 * edge2->pos - edge1->pos ); 2113 edge3->pos -= delta; 2114 if ( edge3->link ) 2115 edge3->link->pos -= delta; 2116 2117 /* move the serifs along with the stem */ 2118 if ( n_edges == 12 ) 2119 { 2120 ( edges + 8 )->pos -= delta; 2121 ( edges + 11 )->pos -= delta; 2122 } 2123 2124 edge3->flags |= AF_EDGE_DONE; 2125 if ( edge3->link ) 2126 edge3->link->flags |= AF_EDGE_DONE; 2127 } 2128 } 2129 2130 if ( has_serifs || !anchor ) 2131 { 2132 /* 2133 * now hint the remaining edges (serifs and single) in order 2134 * to complete our processing 2135 */ 2136 for ( edge = edges; edge < edge_limit; edge++ ) 2137 { 2138 FT_Pos delta; 2139 2140 2141 if ( edge->flags & AF_EDGE_DONE ) 2142 continue; 2143 2144 delta = 1000; 2145 2146 if ( edge->serif ) 2147 { 2148 delta = edge->serif->opos - edge->opos; 2149 if ( delta < 0 ) 2150 delta = -delta; 2151 } 2152 2153 if ( delta < 64 + 16 ) 2154 { 2155 af_latin_align_serif_edge( hints, edge->serif, edge ); 2156 FT_TRACE5(( " SERIF: edge %d (opos=%.2f) serif to %d (opos=%.2f)" 2157 " aligned to (%.2f)\n", 2158 edge - edges, edge->opos / 64.0, 2159 edge->serif - edges, edge->serif->opos / 64.0, 2160 edge->pos / 64.0 )); 2161 } 2162 else if ( !anchor ) 2163 { 2164 edge->pos = FT_PIX_ROUND( edge->opos ); 2165 anchor = edge; 2166 FT_TRACE5(( " SERIF_ANCHOR: edge %d (opos=%.2f)" 2167 " snapped to (%.2f)\n", 2168 edge-edges, edge->opos / 64.0, edge->pos / 64.0 )); 2169 } 2170 else 2171 { 2172 AF_Edge before, after; 2173 2174 2175 for ( before = edge - 1; before >= edges; before-- ) 2176 if ( before->flags & AF_EDGE_DONE ) 2177 break; 2178 2179 for ( after = edge + 1; after < edge_limit; after++ ) 2180 if ( after->flags & AF_EDGE_DONE ) 2181 break; 2182 2183 if ( before >= edges && before < edge && 2184 after < edge_limit && after > edge ) 2185 { 2186 if ( after->opos == before->opos ) 2187 edge->pos = before->pos; 2188 else 2189 edge->pos = before->pos + 2190 FT_MulDiv( edge->opos - before->opos, 2191 after->pos - before->pos, 2192 after->opos - before->opos ); 2193 2194 FT_TRACE5(( " SERIF_LINK1: edge %d (opos=%.2f) snapped to (%.2f)" 2195 " from %d (opos=%.2f)\n", 2196 edge - edges, edge->opos / 64.0, 2197 edge->pos / 64.0, 2198 before - edges, before->opos / 64.0 )); 2199 } 2200 else 2201 { 2202 edge->pos = anchor->pos + 2203 ( ( edge->opos - anchor->opos + 16 ) & ~31 ); 2204 2205 FT_TRACE5(( " SERIF_LINK2: edge %d (opos=%.2f)" 2206 " snapped to (%.2f)\n", 2207 edge - edges, edge->opos / 64.0, edge->pos / 64.0 )); 2208 } 2209 } 2210 2211 edge->flags |= AF_EDGE_DONE; 2212 2213 if ( edge > edges && edge->pos < edge[-1].pos ) 2214 edge->pos = edge[-1].pos; 2215 2216 if ( edge + 1 < edge_limit && 2217 edge[1].flags & AF_EDGE_DONE && 2218 edge->pos > edge[1].pos ) 2219 edge->pos = edge[1].pos; 2220 } 2221 } 2222 2223 FT_TRACE5(( "\n" )); 2224 } 2225 2226 2227 /* Apply the complete hinting algorithm to a latin glyph. */ 2228 2229 static FT_Error af_latin_hints_apply(AF_GlyphHints hints,FT_Outline * outline,AF_LatinMetrics metrics)2230 af_latin_hints_apply( AF_GlyphHints hints, 2231 FT_Outline* outline, 2232 AF_LatinMetrics metrics ) 2233 { 2234 FT_Error error; 2235 int dim; 2236 2237 2238 error = af_glyph_hints_reload( hints, outline ); 2239 if ( error ) 2240 goto Exit; 2241 2242 /* analyze glyph outline */ 2243 #ifdef AF_CONFIG_OPTION_USE_WARPER 2244 if ( metrics->root.scaler.render_mode == FT_RENDER_MODE_LIGHT || 2245 AF_HINTS_DO_HORIZONTAL( hints ) ) 2246 #else 2247 if ( AF_HINTS_DO_HORIZONTAL( hints ) ) 2248 #endif 2249 { 2250 error = af_latin_hints_detect_features( hints, AF_DIMENSION_HORZ ); 2251 if ( error ) 2252 goto Exit; 2253 } 2254 2255 if ( AF_HINTS_DO_VERTICAL( hints ) ) 2256 { 2257 error = af_latin_hints_detect_features( hints, AF_DIMENSION_VERT ); 2258 if ( error ) 2259 goto Exit; 2260 2261 af_latin_hints_compute_blue_edges( hints, metrics ); 2262 } 2263 2264 /* grid-fit the outline */ 2265 for ( dim = 0; dim < AF_DIMENSION_MAX; dim++ ) 2266 { 2267 #ifdef AF_CONFIG_OPTION_USE_WARPER 2268 if ( dim == AF_DIMENSION_HORZ && 2269 metrics->root.scaler.render_mode == FT_RENDER_MODE_LIGHT ) 2270 { 2271 AF_WarperRec warper; 2272 FT_Fixed scale; 2273 FT_Pos delta; 2274 2275 2276 af_warper_compute( &warper, hints, (AF_Dimension)dim, 2277 &scale, &delta ); 2278 af_glyph_hints_scale_dim( hints, (AF_Dimension)dim, 2279 scale, delta ); 2280 continue; 2281 } 2282 #endif 2283 2284 if ( ( dim == AF_DIMENSION_HORZ && AF_HINTS_DO_HORIZONTAL( hints ) ) || 2285 ( dim == AF_DIMENSION_VERT && AF_HINTS_DO_VERTICAL( hints ) ) ) 2286 { 2287 af_latin_hint_edges( hints, (AF_Dimension)dim ); 2288 af_glyph_hints_align_edge_points( hints, (AF_Dimension)dim ); 2289 af_glyph_hints_align_strong_points( hints, (AF_Dimension)dim ); 2290 af_glyph_hints_align_weak_points( hints, (AF_Dimension)dim ); 2291 } 2292 } 2293 af_glyph_hints_save( hints, outline ); 2294 2295 Exit: 2296 return error; 2297 } 2298 2299 2300 /*************************************************************************/ 2301 /*************************************************************************/ 2302 /***** *****/ 2303 /***** L A T I N S C R I P T C L A S S *****/ 2304 /***** *****/ 2305 /*************************************************************************/ 2306 /*************************************************************************/ 2307 2308 2309 /* XXX: this should probably fine tuned to differentiate better between */ 2310 /* scripts... */ 2311 2312 static const AF_Script_UniRangeRec af_latin_uniranges[] = 2313 { 2314 AF_UNIRANGE_REC( 0x0020UL, 0x007FUL ), /* Basic Latin (no control chars) */ 2315 AF_UNIRANGE_REC( 0x00A0UL, 0x00FFUL ), /* Latin-1 Supplement (no control chars) */ 2316 AF_UNIRANGE_REC( 0x0100UL, 0x017FUL ), /* Latin Extended-A */ 2317 AF_UNIRANGE_REC( 0x0180UL, 0x024FUL ), /* Latin Extended-B */ 2318 AF_UNIRANGE_REC( 0x0250UL, 0x02AFUL ), /* IPA Extensions */ 2319 AF_UNIRANGE_REC( 0x02B0UL, 0x02FFUL ), /* Spacing Modifier Letters */ 2320 AF_UNIRANGE_REC( 0x0300UL, 0x036FUL ), /* Combining Diacritical Marks */ 2321 AF_UNIRANGE_REC( 0x0370UL, 0x03FFUL ), /* Greek and Coptic */ 2322 AF_UNIRANGE_REC( 0x0400UL, 0x04FFUL ), /* Cyrillic */ 2323 AF_UNIRANGE_REC( 0x0500UL, 0x052FUL ), /* Cyrillic Supplement */ 2324 AF_UNIRANGE_REC( 0x1D00UL, 0x1D7FUL ), /* Phonetic Extensions */ 2325 AF_UNIRANGE_REC( 0x1D80UL, 0x1DBFUL ), /* Phonetic Extensions Supplement */ 2326 AF_UNIRANGE_REC( 0x1DC0UL, 0x1DFFUL ), /* Combining Diacritical Marks Supplement */ 2327 AF_UNIRANGE_REC( 0x1E00UL, 0x1EFFUL ), /* Latin Extended Additional */ 2328 AF_UNIRANGE_REC( 0x1F00UL, 0x1FFFUL ), /* Greek Extended */ 2329 AF_UNIRANGE_REC( 0x2000UL, 0x206FUL ), /* General Punctuation */ 2330 AF_UNIRANGE_REC( 0x2070UL, 0x209FUL ), /* Superscripts and Subscripts */ 2331 AF_UNIRANGE_REC( 0x20A0UL, 0x20CFUL ), /* Currency Symbols */ 2332 AF_UNIRANGE_REC( 0x2150UL, 0x218FUL ), /* Number Forms */ 2333 AF_UNIRANGE_REC( 0x2460UL, 0x24FFUL ), /* Enclosed Alphanumerics */ 2334 AF_UNIRANGE_REC( 0x2C60UL, 0x2C7FUL ), /* Latin Extended-C */ 2335 AF_UNIRANGE_REC( 0x2DE0UL, 0x2DFFUL ), /* Cyrillic Extended-A */ 2336 AF_UNIRANGE_REC( 0xA640UL, 0xA69FUL ), /* Cyrillic Extended-B */ 2337 AF_UNIRANGE_REC( 0xA720UL, 0xA7FFUL ), /* Latin Extended-D */ 2338 AF_UNIRANGE_REC( 0xFB00UL, 0xFB06UL ), /* Alphab. Present. Forms (Latin Ligs) */ 2339 AF_UNIRANGE_REC( 0x1D400UL, 0x1D7FFUL ), /* Mathematical Alphanumeric Symbols */ 2340 AF_UNIRANGE_REC( 0UL, 0UL ) 2341 }; 2342 2343 2344 AF_DEFINE_SCRIPT_CLASS( af_latin_script_class, 2345 AF_SCRIPT_LATIN, 2346 af_latin_uniranges, 2347 2348 sizeof ( AF_LatinMetricsRec ), 2349 2350 (AF_Script_InitMetricsFunc) af_latin_metrics_init, 2351 (AF_Script_ScaleMetricsFunc)af_latin_metrics_scale, 2352 (AF_Script_DoneMetricsFunc) NULL, 2353 2354 (AF_Script_InitHintsFunc) af_latin_hints_init, 2355 (AF_Script_ApplyHintsFunc) af_latin_hints_apply 2356 ) 2357 2358 2359 /* END */ 2360