1/***************************************************************************/ 2/* */ 3/* cf2hints.c */ 4/* */ 5/* Adobe's code for handling CFF hints (body). */ 6/* */ 7/* Copyright 2007-2014 Adobe Systems Incorporated. */ 8/* */ 9/* This software, and all works of authorship, whether in source or */ 10/* object code form as indicated by the copyright notice(s) included */ 11/* herein (collectively, the "Work") is made available, and may only be */ 12/* used, modified, and distributed under the FreeType Project License, */ 13/* LICENSE.TXT. Additionally, subject to the terms and conditions of the */ 14/* FreeType Project License, each contributor to the Work hereby grants */ 15/* to any individual or legal entity exercising permissions granted by */ 16/* the FreeType Project License and this section (hereafter, "You" or */ 17/* "Your") a perpetual, worldwide, non-exclusive, no-charge, */ 18/* royalty-free, irrevocable (except as stated in this section) patent */ 19/* license to make, have made, use, offer to sell, sell, import, and */ 20/* otherwise transfer the Work, where such license applies only to those */ 21/* patent claims licensable by such contributor that are necessarily */ 22/* infringed by their contribution(s) alone or by combination of their */ 23/* contribution(s) with the Work to which such contribution(s) was */ 24/* submitted. If You institute patent litigation against any entity */ 25/* (including a cross-claim or counterclaim in a lawsuit) alleging that */ 26/* the Work or a contribution incorporated within the Work constitutes */ 27/* direct or contributory patent infringement, then any patent licenses */ 28/* granted to You under this License for that Work shall terminate as of */ 29/* the date such litigation is filed. */ 30/* */ 31/* By using, modifying, or distributing the Work you indicate that you */ 32/* have read and understood the terms and conditions of the */ 33/* FreeType Project License as well as those provided in this section, */ 34/* and you accept them fully. */ 35/* */ 36/***************************************************************************/ 37 38 39#include "cf2ft.h" 40#include FT_INTERNAL_DEBUG_H 41 42#include "cf2glue.h" 43#include "cf2font.h" 44#include "cf2hints.h" 45#include "cf2intrp.h" 46 47 48 /*************************************************************************/ 49 /* */ 50 /* The macro FT_COMPONENT is used in trace mode. It is an implicit */ 51 /* parameter of the FT_TRACE() and FT_ERROR() macros, used to print/log */ 52 /* messages during execution. */ 53 /* */ 54#undef FT_COMPONENT 55#define FT_COMPONENT trace_cf2hints 56 57 58 typedef struct CF2_HintMoveRec_ 59 { 60 size_t j; /* index of upper hint map edge */ 61 CF2_Fixed moveUp; /* adjustment to optimum position */ 62 63 } CF2_HintMoveRec, *CF2_HintMove; 64 65 66 /* Compute angular momentum for winding order detection. It is called */ 67 /* for all lines and curves, but not necessarily in element order. */ 68 static CF2_Int 69 cf2_getWindingMomentum( CF2_Fixed x1, 70 CF2_Fixed y1, 71 CF2_Fixed x2, 72 CF2_Fixed y2 ) 73 { 74 /* cross product of pt1 position from origin with pt2 position from */ 75 /* pt1; we reduce the precision so that the result fits into 32 bits */ 76 77 return ( x1 >> 16 ) * ( ( y2 - y1 ) >> 16 ) - 78 ( y1 >> 16 ) * ( ( x2 - x1 ) >> 16 ); 79 } 80 81 82 /* 83 * Construct from a StemHint; this is used as a parameter to 84 * `cf2_blues_capture'. 85 * `hintOrigin' is the character space displacement of a seac accent. 86 * Adjust stem hint for darkening here. 87 * 88 */ 89 static void 90 cf2_hint_init( CF2_Hint hint, 91 const CF2_ArrStack stemHintArray, 92 size_t indexStemHint, 93 const CF2_Font font, 94 CF2_Fixed hintOrigin, 95 CF2_Fixed scale, 96 FT_Bool bottom ) 97 { 98 CF2_Fixed width; 99 const CF2_StemHintRec* stemHint; 100 101 102 FT_ZERO( hint ); 103 104 stemHint = (const CF2_StemHintRec*)cf2_arrstack_getPointer( 105 stemHintArray, 106 indexStemHint ); 107 108 width = stemHint->max - stemHint->min; 109 110 if ( width == cf2_intToFixed( -21 ) ) 111 { 112 /* ghost bottom */ 113 114 if ( bottom ) 115 { 116 hint->csCoord = stemHint->max; 117 hint->flags = CF2_GhostBottom; 118 } 119 else 120 hint->flags = 0; 121 } 122 123 else if ( width == cf2_intToFixed( -20 ) ) 124 { 125 /* ghost top */ 126 127 if ( bottom ) 128 hint->flags = 0; 129 else 130 { 131 hint->csCoord = stemHint->min; 132 hint->flags = CF2_GhostTop; 133 } 134 } 135 136 else if ( width < 0 ) 137 { 138 /* inverted pair */ 139 140 /* 141 * Hints with negative widths were produced by an early version of a 142 * non-Adobe font tool. The Type 2 spec allows edge (ghost) hints 143 * with negative widths, but says 144 * 145 * All other negative widths have undefined meaning. 146 * 147 * CoolType has a silent workaround that negates the hint width; for 148 * permissive mode, we do the same here. 149 * 150 * Note: Such fonts cannot use ghost hints, but should otherwise work. 151 * Note: Some poor hints in our faux fonts can produce negative 152 * widths at some blends. For example, see a light weight of 153 * `u' in ASerifMM. 154 * 155 */ 156 if ( bottom ) 157 { 158 hint->csCoord = stemHint->max; 159 hint->flags = CF2_PairBottom; 160 } 161 else 162 { 163 hint->csCoord = stemHint->min; 164 hint->flags = CF2_PairTop; 165 } 166 } 167 168 else 169 { 170 /* normal pair */ 171 172 if ( bottom ) 173 { 174 hint->csCoord = stemHint->min; 175 hint->flags = CF2_PairBottom; 176 } 177 else 178 { 179 hint->csCoord = stemHint->max; 180 hint->flags = CF2_PairTop; 181 } 182 } 183 184 /* Now that ghost hints have been detected, adjust this edge for */ 185 /* darkening. Bottoms are not changed; tops are incremented by twice */ 186 /* `darkenY'. */ 187 if ( cf2_hint_isTop( hint ) ) 188 hint->csCoord += 2 * font->darkenY; 189 190 hint->csCoord += hintOrigin; 191 hint->scale = scale; 192 hint->index = indexStemHint; /* index in original stem hint array */ 193 194 /* if original stem hint has been used, use the same position */ 195 if ( hint->flags != 0 && stemHint->used ) 196 { 197 if ( cf2_hint_isTop( hint ) ) 198 hint->dsCoord = stemHint->maxDS; 199 else 200 hint->dsCoord = stemHint->minDS; 201 202 cf2_hint_lock( hint ); 203 } 204 else 205 hint->dsCoord = FT_MulFix( hint->csCoord, scale ); 206 } 207 208 209 /* initialize an invalid hint map element */ 210 static void 211 cf2_hint_initZero( CF2_Hint hint ) 212 { 213 FT_ZERO( hint ); 214 } 215 216 217 FT_LOCAL_DEF( FT_Bool ) 218 cf2_hint_isValid( const CF2_Hint hint ) 219 { 220 return (FT_Bool)( hint->flags != 0 ); 221 } 222 223 224 static FT_Bool 225 cf2_hint_isPair( const CF2_Hint hint ) 226 { 227 return (FT_Bool)( ( hint->flags & 228 ( CF2_PairBottom | CF2_PairTop ) ) != 0 ); 229 } 230 231 232 static FT_Bool 233 cf2_hint_isPairTop( const CF2_Hint hint ) 234 { 235 return (FT_Bool)( ( hint->flags & CF2_PairTop ) != 0 ); 236 } 237 238 239 FT_LOCAL_DEF( FT_Bool ) 240 cf2_hint_isTop( const CF2_Hint hint ) 241 { 242 return (FT_Bool)( ( hint->flags & 243 ( CF2_PairTop | CF2_GhostTop ) ) != 0 ); 244 } 245 246 247 FT_LOCAL_DEF( FT_Bool ) 248 cf2_hint_isBottom( const CF2_Hint hint ) 249 { 250 return (FT_Bool)( ( hint->flags & 251 ( CF2_PairBottom | CF2_GhostBottom ) ) != 0 ); 252 } 253 254 255 static FT_Bool 256 cf2_hint_isLocked( const CF2_Hint hint ) 257 { 258 return (FT_Bool)( ( hint->flags & CF2_Locked ) != 0 ); 259 } 260 261 262 static FT_Bool 263 cf2_hint_isSynthetic( const CF2_Hint hint ) 264 { 265 return (FT_Bool)( ( hint->flags & CF2_Synthetic ) != 0 ); 266 } 267 268 269 FT_LOCAL_DEF( void ) 270 cf2_hint_lock( CF2_Hint hint ) 271 { 272 hint->flags |= CF2_Locked; 273 } 274 275 276 FT_LOCAL_DEF( void ) 277 cf2_hintmap_init( CF2_HintMap hintmap, 278 CF2_Font font, 279 CF2_HintMap initialMap, 280 CF2_ArrStack hintMoves, 281 CF2_Fixed scale ) 282 { 283 FT_ZERO( hintmap ); 284 285 /* copy parameters from font instance */ 286 hintmap->hinted = font->hinted; 287 hintmap->scale = scale; 288 hintmap->font = font; 289 hintmap->initialHintMap = initialMap; 290 /* will clear in `cf2_hintmap_adjustHints' */ 291 hintmap->hintMoves = hintMoves; 292 } 293 294 295 static FT_Bool 296 cf2_hintmap_isValid( const CF2_HintMap hintmap ) 297 { 298 return hintmap->isValid; 299 } 300 301 302 /* transform character space coordinate to device space using hint map */ 303 static CF2_Fixed 304 cf2_hintmap_map( CF2_HintMap hintmap, 305 CF2_Fixed csCoord ) 306 { 307 if ( hintmap->count == 0 || ! hintmap->hinted ) 308 { 309 /* there are no hints; use uniform scale and zero offset */ 310 return FT_MulFix( csCoord, hintmap->scale ); 311 } 312 else 313 { 314 /* start linear search from last hit */ 315 CF2_UInt i = hintmap->lastIndex; 316 317 FT_ASSERT( hintmap->lastIndex < CF2_MAX_HINT_EDGES ); 318 319 /* search up */ 320 while ( i < hintmap->count - 1 && 321 csCoord >= hintmap->edge[i + 1].csCoord ) 322 i += 1; 323 324 /* search down */ 325 while ( i > 0 && csCoord < hintmap->edge[i].csCoord ) 326 i -= 1; 327 328 hintmap->lastIndex = i; 329 330 if ( i == 0 && csCoord < hintmap->edge[0].csCoord ) 331 { 332 /* special case for points below first edge: use uniform scale */ 333 return FT_MulFix( csCoord - hintmap->edge[0].csCoord, 334 hintmap->scale ) + 335 hintmap->edge[0].dsCoord; 336 } 337 else 338 { 339 /* 340 * Note: entries with duplicate csCoord are allowed. 341 * Use edge[i], the highest entry where csCoord >= entry[i].csCoord 342 */ 343 return FT_MulFix( csCoord - hintmap->edge[i].csCoord, 344 hintmap->edge[i].scale ) + 345 hintmap->edge[i].dsCoord; 346 } 347 } 348 } 349 350 351 /* 352 * This hinting policy moves a hint pair in device space so that one of 353 * its two edges is on a device pixel boundary (its fractional part is 354 * zero). `cf2_hintmap_insertHint' guarantees no overlap in CS 355 * space. Ensure here that there is no overlap in DS. 356 * 357 * In the first pass, edges are adjusted relative to adjacent hints. 358 * Those that are below have already been adjusted. Those that are 359 * above have not yet been adjusted. If a hint above blocks an 360 * adjustment to an optimal position, we will try again in a second 361 * pass. The second pass is top-down. 362 * 363 */ 364 365 static void 366 cf2_hintmap_adjustHints( CF2_HintMap hintmap ) 367 { 368 size_t i, j; 369 370 371 cf2_arrstack_clear( hintmap->hintMoves ); /* working storage */ 372 373 /* 374 * First pass is bottom-up (font hint order) without look-ahead. 375 * Locked edges are already adjusted. 376 * Unlocked edges begin with dsCoord from `initialHintMap'. 377 * Save edges that are not optimally adjusted in `hintMoves' array, 378 * and process them in second pass. 379 */ 380 381 for ( i = 0; i < hintmap->count; i++ ) 382 { 383 FT_Bool isPair = cf2_hint_isPair( &hintmap->edge[i] ); 384 385 386 /* index of upper edge (same value for ghost hint) */ 387 j = isPair ? i + 1 : i; 388 389 FT_ASSERT( j < hintmap->count ); 390 FT_ASSERT( cf2_hint_isValid( &hintmap->edge[i] ) ); 391 FT_ASSERT( cf2_hint_isValid( &hintmap->edge[j] ) ); 392 FT_ASSERT( cf2_hint_isLocked( &hintmap->edge[i] ) == 393 cf2_hint_isLocked( &hintmap->edge[j] ) ); 394 395 if ( !cf2_hint_isLocked( &hintmap->edge[i] ) ) 396 { 397 /* hint edge is not locked, we can adjust it */ 398 CF2_Fixed fracDown = cf2_fixedFraction( hintmap->edge[i].dsCoord ); 399 CF2_Fixed fracUp = cf2_fixedFraction( hintmap->edge[j].dsCoord ); 400 401 /* calculate all four possibilities; moves down are negative */ 402 CF2_Fixed downMoveDown = 0 - fracDown; 403 CF2_Fixed upMoveDown = 0 - fracUp; 404 CF2_Fixed downMoveUp = ( fracDown == 0 ) 405 ? 0 406 : cf2_intToFixed( 1 ) - fracDown; 407 CF2_Fixed upMoveUp = ( fracUp == 0 ) 408 ? 0 409 : cf2_intToFixed( 1 ) - fracUp; 410 411 /* smallest move up */ 412 CF2_Fixed moveUp = FT_MIN( downMoveUp, upMoveUp ); 413 /* smallest move down */ 414 CF2_Fixed moveDown = FT_MAX( downMoveDown, upMoveDown ); 415 416 /* final amount to move edge or edge pair */ 417 CF2_Fixed move; 418 419 CF2_Fixed downMinCounter = CF2_MIN_COUNTER; 420 CF2_Fixed upMinCounter = CF2_MIN_COUNTER; 421 FT_Bool saveEdge = FALSE; 422 423 424 /* minimum counter constraint doesn't apply when adjacent edges */ 425 /* are synthetic */ 426 /* TODO: doesn't seem a big effect; for now, reduce the code */ 427#if 0 428 if ( i == 0 || 429 cf2_hint_isSynthetic( &hintmap->edge[i - 1] ) ) 430 downMinCounter = 0; 431 432 if ( j >= hintmap->count - 1 || 433 cf2_hint_isSynthetic( &hintmap->edge[j + 1] ) ) 434 upMinCounter = 0; 435#endif 436 437 /* is there room to move up? */ 438 /* there is if we are at top of array or the next edge is at or */ 439 /* beyond proposed move up? */ 440 if ( j >= hintmap->count - 1 || 441 hintmap->edge[j + 1].dsCoord >= 442 hintmap->edge[j].dsCoord + moveUp + upMinCounter ) 443 { 444 /* there is room to move up; is there also room to move down? */ 445 if ( i == 0 || 446 hintmap->edge[i - 1].dsCoord <= 447 hintmap->edge[i].dsCoord + moveDown - downMinCounter ) 448 { 449 /* move smaller absolute amount */ 450 move = ( -moveDown < moveUp ) ? moveDown : moveUp; /* optimum */ 451 } 452 else 453 move = moveUp; 454 } 455 else 456 { 457 /* is there room to move down? */ 458 if ( i == 0 || 459 hintmap->edge[i - 1].dsCoord <= 460 hintmap->edge[i].dsCoord + moveDown - downMinCounter ) 461 { 462 move = moveDown; 463 /* true if non-optimum move */ 464 saveEdge = (FT_Bool)( moveUp < -moveDown ); 465 } 466 else 467 { 468 /* no room to move either way without overlapping or reducing */ 469 /* the counter too much */ 470 move = 0; 471 saveEdge = TRUE; 472 } 473 } 474 475 /* Identify non-moves and moves down that aren't optimal, and save */ 476 /* them for second pass. */ 477 /* Do this only if there is an unlocked edge above (which could */ 478 /* possibly move). */ 479 if ( saveEdge && 480 j < hintmap->count - 1 && 481 !cf2_hint_isLocked( &hintmap->edge[j + 1] ) ) 482 { 483 CF2_HintMoveRec savedMove; 484 485 486 savedMove.j = j; 487 /* desired adjustment in second pass */ 488 savedMove.moveUp = moveUp - move; 489 490 cf2_arrstack_push( hintmap->hintMoves, &savedMove ); 491 } 492 493 /* move the edge(s) */ 494 hintmap->edge[i].dsCoord += move; 495 if ( isPair ) 496 hintmap->edge[j].dsCoord += move; 497 } 498 499 /* assert there are no overlaps in device space */ 500 FT_ASSERT( i == 0 || 501 hintmap->edge[i - 1].dsCoord <= hintmap->edge[i].dsCoord ); 502 FT_ASSERT( i < j || 503 hintmap->edge[i].dsCoord <= hintmap->edge[j].dsCoord ); 504 505 /* adjust the scales, avoiding divide by zero */ 506 if ( i > 0 ) 507 { 508 if ( hintmap->edge[i].csCoord != hintmap->edge[i - 1].csCoord ) 509 hintmap->edge[i - 1].scale = 510 FT_DivFix( 511 hintmap->edge[i].dsCoord - hintmap->edge[i - 1].dsCoord, 512 hintmap->edge[i].csCoord - hintmap->edge[i - 1].csCoord ); 513 } 514 515 if ( isPair ) 516 { 517 if ( hintmap->edge[j].csCoord != hintmap->edge[j - 1].csCoord ) 518 hintmap->edge[j - 1].scale = 519 FT_DivFix( 520 hintmap->edge[j].dsCoord - hintmap->edge[j - 1].dsCoord, 521 hintmap->edge[j].csCoord - hintmap->edge[j - 1].csCoord ); 522 523 i += 1; /* skip upper edge on next loop */ 524 } 525 } 526 527 /* second pass tries to move non-optimal hints up, in case there is */ 528 /* room now */ 529 for ( i = cf2_arrstack_size( hintmap->hintMoves ); i > 0; i-- ) 530 { 531 CF2_HintMove hintMove = (CF2_HintMove) 532 cf2_arrstack_getPointer( hintmap->hintMoves, i - 1 ); 533 534 535 j = hintMove->j; 536 537 /* this was tested before the push, above */ 538 FT_ASSERT( j < hintmap->count - 1 ); 539 540 /* is there room to move up? */ 541 if ( hintmap->edge[j + 1].dsCoord >= 542 hintmap->edge[j].dsCoord + hintMove->moveUp + CF2_MIN_COUNTER ) 543 { 544 /* there is more room now, move edge up */ 545 hintmap->edge[j].dsCoord += hintMove->moveUp; 546 547 if ( cf2_hint_isPair( &hintmap->edge[j] ) ) 548 { 549 FT_ASSERT( j > 0 ); 550 hintmap->edge[j - 1].dsCoord += hintMove->moveUp; 551 } 552 } 553 } 554 } 555 556 557 /* insert hint edges into map, sorted by csCoord */ 558 static void 559 cf2_hintmap_insertHint( CF2_HintMap hintmap, 560 CF2_Hint bottomHintEdge, 561 CF2_Hint topHintEdge ) 562 { 563 CF2_UInt indexInsert; 564 565 /* set default values, then check for edge hints */ 566 FT_Bool isPair = TRUE; 567 CF2_Hint firstHintEdge = bottomHintEdge; 568 CF2_Hint secondHintEdge = topHintEdge; 569 570 571 /* one or none of the input params may be invalid when dealing with */ 572 /* edge hints; at least one edge must be valid */ 573 FT_ASSERT( cf2_hint_isValid( bottomHintEdge ) || 574 cf2_hint_isValid( topHintEdge ) ); 575 576 /* determine how many and which edges to insert */ 577 if ( !cf2_hint_isValid( bottomHintEdge ) ) 578 { 579 /* insert only the top edge */ 580 firstHintEdge = topHintEdge; 581 isPair = FALSE; 582 } 583 else if ( !cf2_hint_isValid( topHintEdge ) ) 584 { 585 /* insert only the bottom edge */ 586 isPair = FALSE; 587 } 588 589 /* paired edges must be in proper order */ 590 if ( isPair && 591 topHintEdge->csCoord < bottomHintEdge->csCoord ) 592 return; 593 594 /* linear search to find index value of insertion point */ 595 indexInsert = 0; 596 for ( ; indexInsert < hintmap->count; indexInsert++ ) 597 { 598 if ( hintmap->edge[indexInsert].csCoord >= firstHintEdge->csCoord ) 599 break; 600 } 601 602 /* 603 * Discard any hints that overlap in character space. Most often, this 604 * is while building the initial map, where captured hints from all 605 * zones are combined. Define overlap to include hints that `touch' 606 * (overlap zero). Hiragino Sans/Gothic fonts have numerous hints that 607 * touch. Some fonts have non-ideographic glyphs that overlap our 608 * synthetic hints. 609 * 610 * Overlap also occurs when darkening stem hints that are close. 611 * 612 */ 613 if ( indexInsert < hintmap->count ) 614 { 615 /* we are inserting before an existing edge: */ 616 /* verify that an existing edge is not the same */ 617 if ( hintmap->edge[indexInsert].csCoord == firstHintEdge->csCoord ) 618 return; /* ignore overlapping stem hint */ 619 620 /* verify that a new pair does not straddle the next edge */ 621 if ( isPair && 622 hintmap->edge[indexInsert].csCoord <= secondHintEdge->csCoord ) 623 return; /* ignore overlapping stem hint */ 624 625 /* verify that we are not inserting between paired edges */ 626 if ( cf2_hint_isPairTop( &hintmap->edge[indexInsert] ) ) 627 return; /* ignore overlapping stem hint */ 628 } 629 630 /* recompute device space locations using initial hint map */ 631 if ( cf2_hintmap_isValid( hintmap->initialHintMap ) && 632 !cf2_hint_isLocked( firstHintEdge ) ) 633 { 634 if ( isPair ) 635 { 636 /* Use hint map to position the center of stem, and nominal scale */ 637 /* to position the two edges. This preserves the stem width. */ 638 CF2_Fixed midpoint = cf2_hintmap_map( 639 hintmap->initialHintMap, 640 ( secondHintEdge->csCoord + 641 firstHintEdge->csCoord ) / 2 ); 642 CF2_Fixed halfWidth = FT_MulFix( 643 ( secondHintEdge->csCoord - 644 firstHintEdge->csCoord ) / 2, 645 hintmap->scale ); 646 647 648 firstHintEdge->dsCoord = midpoint - halfWidth; 649 secondHintEdge->dsCoord = midpoint + halfWidth; 650 } 651 else 652 firstHintEdge->dsCoord = cf2_hintmap_map( hintmap->initialHintMap, 653 firstHintEdge->csCoord ); 654 } 655 656 /* 657 * Discard any hints that overlap in device space; this can occur 658 * because locked hints have been moved to align with blue zones. 659 * 660 * TODO: Although we might correct this later during adjustment, we 661 * don't currently have a way to delete a conflicting hint once it has 662 * been inserted. See v2.030 MinionPro-Regular, 12 ppem darkened, 663 * initial hint map for second path, glyph 945 (the perispomeni (tilde) 664 * in U+1F6E, Greek omega with psili and perispomeni). Darkening is 665 * 25. Pair 667,747 initially conflicts in design space with top edge 666 * 660. This is because 667 maps to 7.87, and the top edge was 667 * captured by a zone at 8.0. The pair is later successfully inserted 668 * in a zone without the top edge. In this zone it is adjusted to 8.0, 669 * and no longer conflicts with the top edge in design space. This 670 * means it can be included in yet a later zone which does have the top 671 * edge hint. This produces a small mismatch between the first and 672 * last points of this path, even though the hint masks are the same. 673 * The density map difference is tiny (1/256). 674 * 675 */ 676 677 if ( indexInsert > 0 ) 678 { 679 /* we are inserting after an existing edge */ 680 if ( firstHintEdge->dsCoord < hintmap->edge[indexInsert - 1].dsCoord ) 681 return; 682 } 683 684 if ( indexInsert < hintmap->count ) 685 { 686 /* we are inserting before an existing edge */ 687 if ( isPair ) 688 { 689 if ( secondHintEdge->dsCoord > hintmap->edge[indexInsert].dsCoord ) 690 return; 691 } 692 else 693 { 694 if ( firstHintEdge->dsCoord > hintmap->edge[indexInsert].dsCoord ) 695 return; 696 } 697 } 698 699 /* make room to insert */ 700 { 701 CF2_UInt iSrc = hintmap->count - 1; 702 CF2_UInt iDst = isPair ? hintmap->count + 1 : hintmap->count; 703 704 CF2_UInt count = hintmap->count - indexInsert; 705 706 707 if ( iDst >= CF2_MAX_HINT_EDGES ) 708 { 709 FT_TRACE4(( "cf2_hintmap_insertHint: too many hintmaps\n" )); 710 return; 711 } 712 713 while ( count-- ) 714 hintmap->edge[iDst--] = hintmap->edge[iSrc--]; 715 716 /* insert first edge */ 717 hintmap->edge[indexInsert] = *firstHintEdge; /* copy struct */ 718 hintmap->count += 1; 719 720 if ( isPair ) 721 { 722 /* insert second edge */ 723 hintmap->edge[indexInsert + 1] = *secondHintEdge; /* copy struct */ 724 hintmap->count += 1; 725 } 726 } 727 728 return; 729 } 730 731 732 /* 733 * Build a map from hints and mask. 734 * 735 * This function may recur one level if `hintmap->initialHintMap' is not yet 736 * valid. 737 * If `initialMap' is true, simply build initial map. 738 * 739 * Synthetic hints are used in two ways. A hint at zero is inserted, if 740 * needed, in the initial hint map, to prevent translations from 741 * propagating across the origin. If synthetic em box hints are enabled 742 * for ideographic dictionaries, then they are inserted in all hint 743 * maps, including the initial one. 744 * 745 */ 746 FT_LOCAL_DEF( void ) 747 cf2_hintmap_build( CF2_HintMap hintmap, 748 CF2_ArrStack hStemHintArray, 749 CF2_ArrStack vStemHintArray, 750 CF2_HintMask hintMask, 751 CF2_Fixed hintOrigin, 752 FT_Bool initialMap ) 753 { 754 FT_Byte* maskPtr; 755 756 CF2_Font font = hintmap->font; 757 CF2_HintMaskRec tempHintMask; 758 759 size_t bitCount, i; 760 FT_Byte maskByte; 761 762 763 /* check whether initial map is constructed */ 764 if ( !initialMap && !cf2_hintmap_isValid( hintmap->initialHintMap ) ) 765 { 766 /* make recursive call with initialHintMap and temporary mask; */ 767 /* temporary mask will get all bits set, below */ 768 cf2_hintmask_init( &tempHintMask, hintMask->error ); 769 cf2_hintmap_build( hintmap->initialHintMap, 770 hStemHintArray, 771 vStemHintArray, 772 &tempHintMask, 773 hintOrigin, 774 TRUE ); 775 } 776 777 if ( !cf2_hintmask_isValid( hintMask ) ) 778 { 779 /* without a hint mask, assume all hints are active */ 780 cf2_hintmask_setAll( hintMask, 781 cf2_arrstack_size( hStemHintArray ) + 782 cf2_arrstack_size( vStemHintArray ) ); 783 if ( !cf2_hintmask_isValid( hintMask ) ) 784 return; /* too many stem hints */ 785 } 786 787 /* begin by clearing the map */ 788 hintmap->count = 0; 789 hintmap->lastIndex = 0; 790 791 /* make a copy of the hint mask so we can modify it */ 792 tempHintMask = *hintMask; 793 maskPtr = cf2_hintmask_getMaskPtr( &tempHintMask ); 794 795 /* use the hStem hints only, which are first in the mask */ 796 bitCount = cf2_arrstack_size( hStemHintArray ); 797 798 /* Defense-in-depth. Should never return here. */ 799 if ( bitCount > hintMask->bitCount ) 800 return; 801 802 /* synthetic embox hints get highest priority */ 803 if ( font->blues.doEmBoxHints ) 804 { 805 CF2_HintRec dummy; 806 807 808 cf2_hint_initZero( &dummy ); /* invalid hint map element */ 809 810 /* ghost bottom */ 811 cf2_hintmap_insertHint( hintmap, 812 &font->blues.emBoxBottomEdge, 813 &dummy ); 814 /* ghost top */ 815 cf2_hintmap_insertHint( hintmap, 816 &dummy, 817 &font->blues.emBoxTopEdge ); 818 } 819 820 /* insert hints captured by a blue zone or already locked (higher */ 821 /* priority) */ 822 for ( i = 0, maskByte = 0x80; i < bitCount; i++ ) 823 { 824 if ( maskByte & *maskPtr ) 825 { 826 /* expand StemHint into two `CF2_Hint' elements */ 827 CF2_HintRec bottomHintEdge, topHintEdge; 828 829 830 cf2_hint_init( &bottomHintEdge, 831 hStemHintArray, 832 i, 833 font, 834 hintOrigin, 835 hintmap->scale, 836 TRUE /* bottom */ ); 837 cf2_hint_init( &topHintEdge, 838 hStemHintArray, 839 i, 840 font, 841 hintOrigin, 842 hintmap->scale, 843 FALSE /* top */ ); 844 845 if ( cf2_hint_isLocked( &bottomHintEdge ) || 846 cf2_hint_isLocked( &topHintEdge ) || 847 cf2_blues_capture( &font->blues, 848 &bottomHintEdge, 849 &topHintEdge ) ) 850 { 851 /* insert captured hint into map */ 852 cf2_hintmap_insertHint( hintmap, &bottomHintEdge, &topHintEdge ); 853 854 *maskPtr &= ~maskByte; /* turn off the bit for this hint */ 855 } 856 } 857 858 if ( ( i & 7 ) == 7 ) 859 { 860 /* move to next mask byte */ 861 maskPtr++; 862 maskByte = 0x80; 863 } 864 else 865 maskByte >>= 1; 866 } 867 868 /* initial hint map includes only captured hints plus maybe one at 0 */ 869 870 /* 871 * TODO: There is a problem here because we are trying to build a 872 * single hint map containing all captured hints. It is 873 * possible for there to be conflicts between captured hints, 874 * either because of darkening or because the hints are in 875 * separate hint zones (we are ignoring hint zones for the 876 * initial map). An example of the latter is MinionPro-Regular 877 * v2.030 glyph 883 (Greek Capital Alpha with Psili) at 15ppem. 878 * A stem hint for the psili conflicts with the top edge hint 879 * for the base character. The stem hint gets priority because 880 * of its sort order. In glyph 884 (Greek Capital Alpha with 881 * Psili and Oxia), the top of the base character gets a stem 882 * hint, and the psili does not. This creates different initial 883 * maps for the two glyphs resulting in different renderings of 884 * the base character. Will probably defer this either as not 885 * worth the cost or as a font bug. I don't think there is any 886 * good reason for an accent to be captured by an alignment 887 * zone. -darnold 2/12/10 888 */ 889 890 if ( initialMap ) 891 { 892 /* Apply a heuristic that inserts a point for (0,0), unless it's */ 893 /* already covered by a mapping. This locks the baseline for glyphs */ 894 /* that have no baseline hints. */ 895 896 if ( hintmap->count == 0 || 897 hintmap->edge[0].csCoord > 0 || 898 hintmap->edge[hintmap->count - 1].csCoord < 0 ) 899 { 900 /* all edges are above 0 or all edges are below 0; */ 901 /* construct a locked edge hint at 0 */ 902 903 CF2_HintRec edge, invalid; 904 905 906 cf2_hint_initZero( &edge ); 907 908 edge.flags = CF2_GhostBottom | 909 CF2_Locked | 910 CF2_Synthetic; 911 edge.scale = hintmap->scale; 912 913 cf2_hint_initZero( &invalid ); 914 cf2_hintmap_insertHint( hintmap, &edge, &invalid ); 915 } 916 } 917 else 918 { 919 /* insert remaining hints */ 920 921 maskPtr = cf2_hintmask_getMaskPtr( &tempHintMask ); 922 923 for ( i = 0, maskByte = 0x80; i < bitCount; i++ ) 924 { 925 if ( maskByte & *maskPtr ) 926 { 927 CF2_HintRec bottomHintEdge, topHintEdge; 928 929 930 cf2_hint_init( &bottomHintEdge, 931 hStemHintArray, 932 i, 933 font, 934 hintOrigin, 935 hintmap->scale, 936 TRUE /* bottom */ ); 937 cf2_hint_init( &topHintEdge, 938 hStemHintArray, 939 i, 940 font, 941 hintOrigin, 942 hintmap->scale, 943 FALSE /* top */ ); 944 945 cf2_hintmap_insertHint( hintmap, &bottomHintEdge, &topHintEdge ); 946 } 947 948 if ( ( i & 7 ) == 7 ) 949 { 950 /* move to next mask byte */ 951 maskPtr++; 952 maskByte = 0x80; 953 } 954 else 955 maskByte >>= 1; 956 } 957 } 958 959 /* 960 * Note: The following line is a convenient place to break when 961 * debugging hinting. Examine `hintmap->edge' for the list of 962 * enabled hints, then step over the call to see the effect of 963 * adjustment. We stop here first on the recursive call that 964 * creates the initial map, and then on each counter group and 965 * hint zone. 966 */ 967 968 /* adjust positions of hint edges that are not locked to blue zones */ 969 cf2_hintmap_adjustHints( hintmap ); 970 971 /* save the position of all hints that were used in this hint map; */ 972 /* if we use them again, we'll locate them in the same position */ 973 if ( !initialMap ) 974 { 975 for ( i = 0; i < hintmap->count; i++ ) 976 { 977 if ( !cf2_hint_isSynthetic( &hintmap->edge[i] ) ) 978 { 979 /* Note: include both valid and invalid edges */ 980 /* Note: top and bottom edges are copied back separately */ 981 CF2_StemHint stemhint = (CF2_StemHint) 982 cf2_arrstack_getPointer( hStemHintArray, 983 hintmap->edge[i].index ); 984 985 986 if ( cf2_hint_isTop( &hintmap->edge[i] ) ) 987 stemhint->maxDS = hintmap->edge[i].dsCoord; 988 else 989 stemhint->minDS = hintmap->edge[i].dsCoord; 990 991 stemhint->used = TRUE; 992 } 993 } 994 } 995 996 /* hint map is ready to use */ 997 hintmap->isValid = TRUE; 998 999 /* remember this mask has been used */ 1000 cf2_hintmask_setNew( hintMask, FALSE ); 1001 } 1002 1003 1004 FT_LOCAL_DEF( void ) 1005 cf2_glyphpath_init( CF2_GlyphPath glyphpath, 1006 CF2_Font font, 1007 CF2_OutlineCallbacks callbacks, 1008 CF2_Fixed scaleY, 1009 /* CF2_Fixed hShift, */ 1010 CF2_ArrStack hStemHintArray, 1011 CF2_ArrStack vStemHintArray, 1012 CF2_HintMask hintMask, 1013 CF2_Fixed hintOriginY, 1014 const CF2_Blues blues, 1015 const FT_Vector* fractionalTranslation ) 1016 { 1017 FT_ZERO( glyphpath ); 1018 1019 glyphpath->font = font; 1020 glyphpath->callbacks = callbacks; 1021 1022 cf2_arrstack_init( &glyphpath->hintMoves, 1023 font->memory, 1024 &font->error, 1025 sizeof ( CF2_HintMoveRec ) ); 1026 1027 cf2_hintmap_init( &glyphpath->initialHintMap, 1028 font, 1029 &glyphpath->initialHintMap, 1030 &glyphpath->hintMoves, 1031 scaleY ); 1032 cf2_hintmap_init( &glyphpath->firstHintMap, 1033 font, 1034 &glyphpath->initialHintMap, 1035 &glyphpath->hintMoves, 1036 scaleY ); 1037 cf2_hintmap_init( &glyphpath->hintMap, 1038 font, 1039 &glyphpath->initialHintMap, 1040 &glyphpath->hintMoves, 1041 scaleY ); 1042 1043 glyphpath->scaleX = font->innerTransform.a; 1044 glyphpath->scaleC = font->innerTransform.c; 1045 glyphpath->scaleY = font->innerTransform.d; 1046 1047 glyphpath->fractionalTranslation = *fractionalTranslation; 1048 1049#if 0 1050 glyphpath->hShift = hShift; /* for fauxing */ 1051#endif 1052 1053 glyphpath->hStemHintArray = hStemHintArray; 1054 glyphpath->vStemHintArray = vStemHintArray; 1055 glyphpath->hintMask = hintMask; /* ptr to current mask */ 1056 glyphpath->hintOriginY = hintOriginY; 1057 glyphpath->blues = blues; 1058 glyphpath->darken = font->darkened; /* TODO: should we make copies? */ 1059 glyphpath->xOffset = font->darkenX; 1060 glyphpath->yOffset = font->darkenY; 1061 glyphpath->miterLimit = 2 * FT_MAX( 1062 cf2_fixedAbs( glyphpath->xOffset ), 1063 cf2_fixedAbs( glyphpath->yOffset ) ); 1064 1065 /* .1 character space unit */ 1066 glyphpath->snapThreshold = cf2_floatToFixed( 0.1f ); 1067 1068 glyphpath->moveIsPending = TRUE; 1069 glyphpath->pathIsOpen = FALSE; 1070 glyphpath->pathIsClosing = FALSE; 1071 glyphpath->elemIsQueued = FALSE; 1072 } 1073 1074 1075 FT_LOCAL_DEF( void ) 1076 cf2_glyphpath_finalize( CF2_GlyphPath glyphpath ) 1077 { 1078 cf2_arrstack_finalize( &glyphpath->hintMoves ); 1079 } 1080 1081 1082 /* 1083 * Hint point in y-direction and apply outerTransform. 1084 * Input `current' hint map (which is actually delayed by one element). 1085 * Input x,y point in Character Space. 1086 * Output x,y point in Device Space, including translation. 1087 */ 1088 static void 1089 cf2_glyphpath_hintPoint( CF2_GlyphPath glyphpath, 1090 CF2_HintMap hintmap, 1091 FT_Vector* ppt, 1092 CF2_Fixed x, 1093 CF2_Fixed y ) 1094 { 1095 FT_Vector pt; /* hinted point in upright DS */ 1096 1097 1098 pt.x = FT_MulFix( glyphpath->scaleX, x ) + 1099 FT_MulFix( glyphpath->scaleC, y ); 1100 pt.y = cf2_hintmap_map( hintmap, y ); 1101 1102 ppt->x = FT_MulFix( glyphpath->font->outerTransform.a, pt.x ) + 1103 FT_MulFix( glyphpath->font->outerTransform.c, pt.y ) + 1104 glyphpath->fractionalTranslation.x; 1105 ppt->y = FT_MulFix( glyphpath->font->outerTransform.b, pt.x ) + 1106 FT_MulFix( glyphpath->font->outerTransform.d, pt.y ) + 1107 glyphpath->fractionalTranslation.y; 1108 } 1109 1110 1111 /* 1112 * From two line segments, (u1,u2) and (v1,v2), compute a point of 1113 * intersection on the corresponding lines. 1114 * Return false if no intersection is found, or if the intersection is 1115 * too far away from the ends of the line segments, u2 and v1. 1116 * 1117 */ 1118 static FT_Bool 1119 cf2_glyphpath_computeIntersection( CF2_GlyphPath glyphpath, 1120 const FT_Vector* u1, 1121 const FT_Vector* u2, 1122 const FT_Vector* v1, 1123 const FT_Vector* v2, 1124 FT_Vector* intersection ) 1125 { 1126 /* 1127 * Let `u' be a zero-based vector from the first segment, `v' from the 1128 * second segment. 1129 * Let `w 'be the zero-based vector from `u1' to `v1'. 1130 * `perp' is the `perpendicular dot product'; see 1131 * http://mathworld.wolfram.com/PerpDotProduct.html. 1132 * `s' is the parameter for the parametric line for the first segment 1133 * (`u'). 1134 * 1135 * See notation in 1136 * http://softsurfer.com/Archive/algorithm_0104/algorithm_0104B.htm. 1137 * Calculations are done in 16.16, but must handle the squaring of 1138 * line lengths in character space. We scale all vectors by 1/32 to 1139 * avoid overflow. This allows values up to 4095 to be squared. The 1140 * scale factor cancels in the divide. 1141 * 1142 * TODO: the scale factor could be computed from UnitsPerEm. 1143 * 1144 */ 1145 1146#define cf2_perp( a, b ) \ 1147 ( FT_MulFix( a.x, b.y ) - FT_MulFix( a.y, b.x ) ) 1148 1149 /* round and divide by 32 */ 1150#define CF2_CS_SCALE( x ) \ 1151 ( ( (x) + 0x10 ) >> 5 ) 1152 1153 FT_Vector u, v, w; /* scaled vectors */ 1154 CF2_Fixed denominator, s; 1155 1156 1157 u.x = CF2_CS_SCALE( u2->x - u1->x ); 1158 u.y = CF2_CS_SCALE( u2->y - u1->y ); 1159 v.x = CF2_CS_SCALE( v2->x - v1->x ); 1160 v.y = CF2_CS_SCALE( v2->y - v1->y ); 1161 w.x = CF2_CS_SCALE( v1->x - u1->x ); 1162 w.y = CF2_CS_SCALE( v1->y - u1->y ); 1163 1164 denominator = cf2_perp( u, v ); 1165 1166 if ( denominator == 0 ) 1167 return FALSE; /* parallel or coincident lines */ 1168 1169 s = FT_DivFix( cf2_perp( w, v ), denominator ); 1170 1171 intersection->x = u1->x + FT_MulFix( s, u2->x - u1->x ); 1172 intersection->y = u1->y + FT_MulFix( s, u2->y - u1->y ); 1173 1174 /* 1175 * Special case snapping for horizontal and vertical lines. 1176 * This cleans up intersections and reduces problems with winding 1177 * order detection. 1178 * Sample case is sbc cd KozGoPr6N-Medium.otf 20 16685. 1179 * Note: these calculations are in character space. 1180 * 1181 */ 1182 1183 if ( u1->x == u2->x && 1184 cf2_fixedAbs( intersection->x - u1->x ) < glyphpath->snapThreshold ) 1185 intersection->x = u1->x; 1186 if ( u1->y == u2->y && 1187 cf2_fixedAbs( intersection->y - u1->y ) < glyphpath->snapThreshold ) 1188 intersection->y = u1->y; 1189 1190 if ( v1->x == v2->x && 1191 cf2_fixedAbs( intersection->x - v1->x ) < glyphpath->snapThreshold ) 1192 intersection->x = v1->x; 1193 if ( v1->y == v2->y && 1194 cf2_fixedAbs( intersection->y - v1->y ) < glyphpath->snapThreshold ) 1195 intersection->y = v1->y; 1196 1197 /* limit the intersection distance from midpoint of u2 and v1 */ 1198 if ( cf2_fixedAbs( intersection->x - ( u2->x + v1->x ) / 2 ) > 1199 glyphpath->miterLimit || 1200 cf2_fixedAbs( intersection->y - ( u2->y + v1->y ) / 2 ) > 1201 glyphpath->miterLimit ) 1202 return FALSE; 1203 1204 return TRUE; 1205 } 1206 1207 1208 /* 1209 * Push the cached element (glyphpath->prevElem*) to the outline 1210 * consumer. When a darkening offset is used, the end point of the 1211 * cached element may be adjusted to an intersection point or we may 1212 * synthesize a connecting line to the current element. If we are 1213 * closing a subpath, we may also generate a connecting line to the start 1214 * point. 1215 * 1216 * This is where Character Space (CS) is converted to Device Space (DS) 1217 * using a hint map. This calculation must use a HintMap that was valid 1218 * at the time the element was saved. For the first point in a subpath, 1219 * that is a saved HintMap. For most elements, it just means the caller 1220 * has delayed building a HintMap from the current HintMask. 1221 * 1222 * Transform each point with outerTransform and call the outline 1223 * callbacks. This is a general 3x3 transform: 1224 * 1225 * x' = a*x + c*y + tx, y' = b*x + d*y + ty 1226 * 1227 * but it uses 4 elements from CF2_Font and the translation part 1228 * from CF2_GlyphPath. 1229 * 1230 */ 1231 static void 1232 cf2_glyphpath_pushPrevElem( CF2_GlyphPath glyphpath, 1233 CF2_HintMap hintmap, 1234 FT_Vector* nextP0, 1235 FT_Vector nextP1, 1236 FT_Bool close ) 1237 { 1238 CF2_CallbackParamsRec params; 1239 1240 FT_Vector* prevP0; 1241 FT_Vector* prevP1; 1242 1243 FT_Vector intersection = { 0, 0 }; 1244 FT_Bool useIntersection = FALSE; 1245 1246 1247 FT_ASSERT( glyphpath->prevElemOp == CF2_PathOpLineTo || 1248 glyphpath->prevElemOp == CF2_PathOpCubeTo ); 1249 1250 if ( glyphpath->prevElemOp == CF2_PathOpLineTo ) 1251 { 1252 prevP0 = &glyphpath->prevElemP0; 1253 prevP1 = &glyphpath->prevElemP1; 1254 } 1255 else 1256 { 1257 prevP0 = &glyphpath->prevElemP2; 1258 prevP1 = &glyphpath->prevElemP3; 1259 } 1260 1261 /* optimization: if previous and next elements are offset by the same */ 1262 /* amount, then there will be no gap, and no need to compute an */ 1263 /* intersection. */ 1264 if ( prevP1->x != nextP0->x || prevP1->y != nextP0->y ) 1265 { 1266 /* previous element does not join next element: */ 1267 /* adjust end point of previous element to the intersection */ 1268 useIntersection = cf2_glyphpath_computeIntersection( glyphpath, 1269 prevP0, 1270 prevP1, 1271 nextP0, 1272 &nextP1, 1273 &intersection ); 1274 if ( useIntersection ) 1275 { 1276 /* modify the last point of the cached element (either line or */ 1277 /* curve) */ 1278 *prevP1 = intersection; 1279 } 1280 } 1281 1282 params.pt0 = glyphpath->currentDS; 1283 1284 switch( glyphpath->prevElemOp ) 1285 { 1286 case CF2_PathOpLineTo: 1287 params.op = CF2_PathOpLineTo; 1288 1289 /* note: pt2 and pt3 are unused */ 1290 1291 if ( close ) 1292 { 1293 /* use first hint map if closing */ 1294 cf2_glyphpath_hintPoint( glyphpath, 1295 &glyphpath->firstHintMap, 1296 ¶ms.pt1, 1297 glyphpath->prevElemP1.x, 1298 glyphpath->prevElemP1.y ); 1299 } 1300 else 1301 { 1302 cf2_glyphpath_hintPoint( glyphpath, 1303 hintmap, 1304 ¶ms.pt1, 1305 glyphpath->prevElemP1.x, 1306 glyphpath->prevElemP1.y ); 1307 } 1308 1309 /* output only non-zero length lines */ 1310 if ( params.pt0.x != params.pt1.x || params.pt0.y != params.pt1.y ) 1311 { 1312 glyphpath->callbacks->lineTo( glyphpath->callbacks, ¶ms ); 1313 1314 glyphpath->currentDS = params.pt1; 1315 } 1316 break; 1317 1318 case CF2_PathOpCubeTo: 1319 params.op = CF2_PathOpCubeTo; 1320 1321 /* TODO: should we intersect the interior joins (p1-p2 and p2-p3)? */ 1322 cf2_glyphpath_hintPoint( glyphpath, 1323 hintmap, 1324 ¶ms.pt1, 1325 glyphpath->prevElemP1.x, 1326 glyphpath->prevElemP1.y ); 1327 cf2_glyphpath_hintPoint( glyphpath, 1328 hintmap, 1329 ¶ms.pt2, 1330 glyphpath->prevElemP2.x, 1331 glyphpath->prevElemP2.y ); 1332 cf2_glyphpath_hintPoint( glyphpath, 1333 hintmap, 1334 ¶ms.pt3, 1335 glyphpath->prevElemP3.x, 1336 glyphpath->prevElemP3.y ); 1337 1338 glyphpath->callbacks->cubeTo( glyphpath->callbacks, ¶ms ); 1339 1340 glyphpath->currentDS = params.pt3; 1341 1342 break; 1343 } 1344 1345 if ( !useIntersection || close ) 1346 { 1347 /* insert connecting line between end of previous element and start */ 1348 /* of current one */ 1349 /* note: at the end of a subpath, we might do both, so use `nextP0' */ 1350 /* before we change it, below */ 1351 1352 if ( close ) 1353 { 1354 /* if we are closing the subpath, then nextP0 is in the first */ 1355 /* hint zone */ 1356 cf2_glyphpath_hintPoint( glyphpath, 1357 &glyphpath->firstHintMap, 1358 ¶ms.pt1, 1359 nextP0->x, 1360 nextP0->y ); 1361 } 1362 else 1363 { 1364 cf2_glyphpath_hintPoint( glyphpath, 1365 hintmap, 1366 ¶ms.pt1, 1367 nextP0->x, 1368 nextP0->y ); 1369 } 1370 1371 if ( params.pt1.x != glyphpath->currentDS.x || 1372 params.pt1.y != glyphpath->currentDS.y ) 1373 { 1374 /* length is nonzero */ 1375 params.op = CF2_PathOpLineTo; 1376 params.pt0 = glyphpath->currentDS; 1377 1378 /* note: pt2 and pt3 are unused */ 1379 glyphpath->callbacks->lineTo( glyphpath->callbacks, ¶ms ); 1380 1381 glyphpath->currentDS = params.pt1; 1382 } 1383 } 1384 1385 if ( useIntersection ) 1386 { 1387 /* return intersection point to caller */ 1388 *nextP0 = intersection; 1389 } 1390 } 1391 1392 1393 /* push a MoveTo element based on current point and offset of current */ 1394 /* element */ 1395 static void 1396 cf2_glyphpath_pushMove( CF2_GlyphPath glyphpath, 1397 FT_Vector start ) 1398 { 1399 CF2_CallbackParamsRec params; 1400 1401 1402 params.op = CF2_PathOpMoveTo; 1403 params.pt0 = glyphpath->currentDS; 1404 1405 /* Test if move has really happened yet; it would have called */ 1406 /* `cf2_hintmap_build' to set `isValid'. */ 1407 if ( !cf2_hintmap_isValid( &glyphpath->hintMap ) ) 1408 { 1409 /* we are here iff first subpath is missing a moveto operator: */ 1410 /* synthesize first moveTo to finish initialization of hintMap */ 1411 cf2_glyphpath_moveTo( glyphpath, 1412 glyphpath->start.x, 1413 glyphpath->start.y ); 1414 } 1415 1416 cf2_glyphpath_hintPoint( glyphpath, 1417 &glyphpath->hintMap, 1418 ¶ms.pt1, 1419 start.x, 1420 start.y ); 1421 1422 /* note: pt2 and pt3 are unused */ 1423 glyphpath->callbacks->moveTo( glyphpath->callbacks, ¶ms ); 1424 1425 glyphpath->currentDS = params.pt1; 1426 glyphpath->offsetStart0 = start; 1427 } 1428 1429 1430 /* 1431 * All coordinates are in character space. 1432 * On input, (x1, y1) and (x2, y2) give line segment. 1433 * On output, (x, y) give offset vector. 1434 * We use a piecewise approximation to trig functions. 1435 * 1436 * TODO: Offset true perpendicular and proper length 1437 * supply the y-translation for hinting here, too, 1438 * that adds yOffset unconditionally to *y. 1439 */ 1440 static void 1441 cf2_glyphpath_computeOffset( CF2_GlyphPath glyphpath, 1442 CF2_Fixed x1, 1443 CF2_Fixed y1, 1444 CF2_Fixed x2, 1445 CF2_Fixed y2, 1446 CF2_Fixed* x, 1447 CF2_Fixed* y ) 1448 { 1449 CF2_Fixed dx = x2 - x1; 1450 CF2_Fixed dy = y2 - y1; 1451 1452 1453 /* note: negative offsets don't work here; negate deltas to change */ 1454 /* quadrants, below */ 1455 if ( glyphpath->font->reverseWinding ) 1456 { 1457 dx = -dx; 1458 dy = -dy; 1459 } 1460 1461 *x = *y = 0; 1462 1463 if ( !glyphpath->darken ) 1464 return; 1465 1466 /* add momentum for this path element */ 1467 glyphpath->callbacks->windingMomentum += 1468 cf2_getWindingMomentum( x1, y1, x2, y2 ); 1469 1470 /* note: allow mixed integer and fixed multiplication here */ 1471 if ( dx >= 0 ) 1472 { 1473 if ( dy >= 0 ) 1474 { 1475 /* first quadrant, +x +y */ 1476 1477 if ( dx > 2 * dy ) 1478 { 1479 /* +x */ 1480 *x = 0; 1481 *y = 0; 1482 } 1483 else if ( dy > 2 * dx ) 1484 { 1485 /* +y */ 1486 *x = glyphpath->xOffset; 1487 *y = glyphpath->yOffset; 1488 } 1489 else 1490 { 1491 /* +x +y */ 1492 *x = FT_MulFix( cf2_floatToFixed( 0.7 ), 1493 glyphpath->xOffset ); 1494 *y = FT_MulFix( cf2_floatToFixed( 1.0 - 0.7 ), 1495 glyphpath->yOffset ); 1496 } 1497 } 1498 else 1499 { 1500 /* fourth quadrant, +x -y */ 1501 1502 if ( dx > -2 * dy ) 1503 { 1504 /* +x */ 1505 *x = 0; 1506 *y = 0; 1507 } 1508 else if ( -dy > 2 * dx ) 1509 { 1510 /* -y */ 1511 *x = -glyphpath->xOffset; 1512 *y = glyphpath->yOffset; 1513 } 1514 else 1515 { 1516 /* +x -y */ 1517 *x = FT_MulFix( cf2_floatToFixed( -0.7 ), 1518 glyphpath->xOffset ); 1519 *y = FT_MulFix( cf2_floatToFixed( 1.0 - 0.7 ), 1520 glyphpath->yOffset ); 1521 } 1522 } 1523 } 1524 else 1525 { 1526 if ( dy >= 0 ) 1527 { 1528 /* second quadrant, -x +y */ 1529 1530 if ( -dx > 2 * dy ) 1531 { 1532 /* -x */ 1533 *x = 0; 1534 *y = 2 * glyphpath->yOffset; 1535 } 1536 else if ( dy > -2 * dx ) 1537 { 1538 /* +y */ 1539 *x = glyphpath->xOffset; 1540 *y = glyphpath->yOffset; 1541 } 1542 else 1543 { 1544 /* -x +y */ 1545 *x = FT_MulFix( cf2_floatToFixed( 0.7 ), 1546 glyphpath->xOffset ); 1547 *y = FT_MulFix( cf2_floatToFixed( 1.0 + 0.7 ), 1548 glyphpath->yOffset ); 1549 } 1550 } 1551 else 1552 { 1553 /* third quadrant, -x -y */ 1554 1555 if ( -dx > -2 * dy ) 1556 { 1557 /* -x */ 1558 *x = 0; 1559 *y = 2 * glyphpath->yOffset; 1560 } 1561 else if ( -dy > -2 * dx ) 1562 { 1563 /* -y */ 1564 *x = -glyphpath->xOffset; 1565 *y = glyphpath->yOffset; 1566 } 1567 else 1568 { 1569 /* -x -y */ 1570 *x = FT_MulFix( cf2_floatToFixed( -0.7 ), 1571 glyphpath->xOffset ); 1572 *y = FT_MulFix( cf2_floatToFixed( 1.0 + 0.7 ), 1573 glyphpath->yOffset ); 1574 } 1575 } 1576 } 1577 } 1578 1579 1580 /* 1581 * The functions cf2_glyphpath_{moveTo,lineTo,curveTo,closeOpenPath} are 1582 * called by the interpreter with Character Space (CS) coordinates. Each 1583 * path element is placed into a queue of length one to await the 1584 * calculation of the following element. At that time, the darkening 1585 * offset of the following element is known and joins can be computed, 1586 * including possible modification of this element, before mapping to 1587 * Device Space (DS) and passing it on to the outline consumer. 1588 * 1589 */ 1590 FT_LOCAL_DEF( void ) 1591 cf2_glyphpath_moveTo( CF2_GlyphPath glyphpath, 1592 CF2_Fixed x, 1593 CF2_Fixed y ) 1594 { 1595 cf2_glyphpath_closeOpenPath( glyphpath ); 1596 1597 /* save the parameters of the move for later, when we'll know how to */ 1598 /* offset it; */ 1599 /* also save last move point */ 1600 glyphpath->currentCS.x = glyphpath->start.x = x; 1601 glyphpath->currentCS.y = glyphpath->start.y = y; 1602 1603 glyphpath->moveIsPending = TRUE; 1604 1605 /* ensure we have a valid map with current mask */ 1606 if ( !cf2_hintmap_isValid( &glyphpath->hintMap ) || 1607 cf2_hintmask_isNew( glyphpath->hintMask ) ) 1608 cf2_hintmap_build( &glyphpath->hintMap, 1609 glyphpath->hStemHintArray, 1610 glyphpath->vStemHintArray, 1611 glyphpath->hintMask, 1612 glyphpath->hintOriginY, 1613 FALSE ); 1614 1615 /* save a copy of current HintMap to use when drawing initial point */ 1616 glyphpath->firstHintMap = glyphpath->hintMap; /* structure copy */ 1617 } 1618 1619 1620 FT_LOCAL_DEF( void ) 1621 cf2_glyphpath_lineTo( CF2_GlyphPath glyphpath, 1622 CF2_Fixed x, 1623 CF2_Fixed y ) 1624 { 1625 CF2_Fixed xOffset, yOffset; 1626 FT_Vector P0, P1; 1627 FT_Bool newHintMap; 1628 1629 /* 1630 * New hints will be applied after cf2_glyphpath_pushPrevElem has run. 1631 * In case this is a synthesized closing line, any new hints should be 1632 * delayed until this path is closed (`cf2_hintmask_isNew' will be 1633 * called again before the next line or curve). 1634 */ 1635 1636 /* true if new hint map not on close */ 1637 newHintMap = cf2_hintmask_isNew( glyphpath->hintMask ) && 1638 !glyphpath->pathIsClosing; 1639 1640 /* 1641 * Zero-length lines may occur in the charstring. Because we cannot 1642 * compute darkening offsets or intersections from zero-length lines, 1643 * it is best to remove them and avoid artifacts. However, zero-length 1644 * lines in CS at the start of a new hint map can generate non-zero 1645 * lines in DS due to hint substitution. We detect a change in hint 1646 * map here and pass those zero-length lines along. 1647 */ 1648 1649 /* 1650 * Note: Find explicitly closed paths here with a conditional 1651 * breakpoint using 1652 * 1653 * !gp->pathIsClosing && gp->start.x == x && gp->start.y == y 1654 * 1655 */ 1656 1657 if ( glyphpath->currentCS.x == x && 1658 glyphpath->currentCS.y == y && 1659 !newHintMap ) 1660 /* 1661 * Ignore zero-length lines in CS where the hint map is the same 1662 * because the line in DS will also be zero length. 1663 * 1664 * Ignore zero-length lines when we synthesize a closing line because 1665 * the close will be handled in cf2_glyphPath_pushPrevElem. 1666 */ 1667 return; 1668 1669 cf2_glyphpath_computeOffset( glyphpath, 1670 glyphpath->currentCS.x, 1671 glyphpath->currentCS.y, 1672 x, 1673 y, 1674 &xOffset, 1675 &yOffset ); 1676 1677 /* construct offset points */ 1678 P0.x = glyphpath->currentCS.x + xOffset; 1679 P0.y = glyphpath->currentCS.y + yOffset; 1680 P1.x = x + xOffset; 1681 P1.y = y + yOffset; 1682 1683 if ( glyphpath->moveIsPending ) 1684 { 1685 /* emit offset 1st point as MoveTo */ 1686 cf2_glyphpath_pushMove( glyphpath, P0 ); 1687 1688 glyphpath->moveIsPending = FALSE; /* adjust state machine */ 1689 glyphpath->pathIsOpen = TRUE; 1690 1691 glyphpath->offsetStart1 = P1; /* record second point */ 1692 } 1693 1694 if ( glyphpath->elemIsQueued ) 1695 { 1696 FT_ASSERT( cf2_hintmap_isValid( &glyphpath->hintMap ) || 1697 glyphpath->hintMap.count == 0 ); 1698 1699 cf2_glyphpath_pushPrevElem( glyphpath, 1700 &glyphpath->hintMap, 1701 &P0, 1702 P1, 1703 FALSE ); 1704 } 1705 1706 /* queue the current element with offset points */ 1707 glyphpath->elemIsQueued = TRUE; 1708 glyphpath->prevElemOp = CF2_PathOpLineTo; 1709 glyphpath->prevElemP0 = P0; 1710 glyphpath->prevElemP1 = P1; 1711 1712 /* update current map */ 1713 if ( newHintMap ) 1714 cf2_hintmap_build( &glyphpath->hintMap, 1715 glyphpath->hStemHintArray, 1716 glyphpath->vStemHintArray, 1717 glyphpath->hintMask, 1718 glyphpath->hintOriginY, 1719 FALSE ); 1720 1721 glyphpath->currentCS.x = x; /* pre-offset current point */ 1722 glyphpath->currentCS.y = y; 1723 } 1724 1725 1726 FT_LOCAL_DEF( void ) 1727 cf2_glyphpath_curveTo( CF2_GlyphPath glyphpath, 1728 CF2_Fixed x1, 1729 CF2_Fixed y1, 1730 CF2_Fixed x2, 1731 CF2_Fixed y2, 1732 CF2_Fixed x3, 1733 CF2_Fixed y3 ) 1734 { 1735 CF2_Fixed xOffset1, yOffset1, xOffset3, yOffset3; 1736 FT_Vector P0, P1, P2, P3; 1737 1738 1739 /* TODO: ignore zero length portions of curve?? */ 1740 cf2_glyphpath_computeOffset( glyphpath, 1741 glyphpath->currentCS.x, 1742 glyphpath->currentCS.y, 1743 x1, 1744 y1, 1745 &xOffset1, 1746 &yOffset1 ); 1747 cf2_glyphpath_computeOffset( glyphpath, 1748 x2, 1749 y2, 1750 x3, 1751 y3, 1752 &xOffset3, 1753 &yOffset3 ); 1754 1755 /* add momentum from the middle segment */ 1756 glyphpath->callbacks->windingMomentum += 1757 cf2_getWindingMomentum( x1, y1, x2, y2 ); 1758 1759 /* construct offset points */ 1760 P0.x = glyphpath->currentCS.x + xOffset1; 1761 P0.y = glyphpath->currentCS.y + yOffset1; 1762 P1.x = x1 + xOffset1; 1763 P1.y = y1 + yOffset1; 1764 /* note: preserve angle of final segment by using offset3 at both ends */ 1765 P2.x = x2 + xOffset3; 1766 P2.y = y2 + yOffset3; 1767 P3.x = x3 + xOffset3; 1768 P3.y = y3 + yOffset3; 1769 1770 if ( glyphpath->moveIsPending ) 1771 { 1772 /* emit offset 1st point as MoveTo */ 1773 cf2_glyphpath_pushMove( glyphpath, P0 ); 1774 1775 glyphpath->moveIsPending = FALSE; 1776 glyphpath->pathIsOpen = TRUE; 1777 1778 glyphpath->offsetStart1 = P1; /* record second point */ 1779 } 1780 1781 if ( glyphpath->elemIsQueued ) 1782 { 1783 FT_ASSERT( cf2_hintmap_isValid( &glyphpath->hintMap ) || 1784 glyphpath->hintMap.count == 0 ); 1785 1786 cf2_glyphpath_pushPrevElem( glyphpath, 1787 &glyphpath->hintMap, 1788 &P0, 1789 P1, 1790 FALSE ); 1791 } 1792 1793 /* queue the current element with offset points */ 1794 glyphpath->elemIsQueued = TRUE; 1795 glyphpath->prevElemOp = CF2_PathOpCubeTo; 1796 glyphpath->prevElemP0 = P0; 1797 glyphpath->prevElemP1 = P1; 1798 glyphpath->prevElemP2 = P2; 1799 glyphpath->prevElemP3 = P3; 1800 1801 /* update current map */ 1802 if ( cf2_hintmask_isNew( glyphpath->hintMask ) ) 1803 cf2_hintmap_build( &glyphpath->hintMap, 1804 glyphpath->hStemHintArray, 1805 glyphpath->vStemHintArray, 1806 glyphpath->hintMask, 1807 glyphpath->hintOriginY, 1808 FALSE ); 1809 1810 glyphpath->currentCS.x = x3; /* pre-offset current point */ 1811 glyphpath->currentCS.y = y3; 1812 } 1813 1814 1815 FT_LOCAL_DEF( void ) 1816 cf2_glyphpath_closeOpenPath( CF2_GlyphPath glyphpath ) 1817 { 1818 if ( glyphpath->pathIsOpen ) 1819 { 1820 /* 1821 * A closing line in Character Space line is always generated below 1822 * with `cf2_glyphPath_lineTo'. It may be ignored later if it turns 1823 * out to be zero length in Device Space. 1824 */ 1825 glyphpath->pathIsClosing = TRUE; 1826 1827 cf2_glyphpath_lineTo( glyphpath, 1828 glyphpath->start.x, 1829 glyphpath->start.y ); 1830 1831 /* empty the final element from the queue and close the path */ 1832 if ( glyphpath->elemIsQueued ) 1833 cf2_glyphpath_pushPrevElem( glyphpath, 1834 &glyphpath->hintMap, 1835 &glyphpath->offsetStart0, 1836 glyphpath->offsetStart1, 1837 TRUE ); 1838 1839 /* reset state machine */ 1840 glyphpath->moveIsPending = TRUE; 1841 glyphpath->pathIsOpen = FALSE; 1842 glyphpath->pathIsClosing = FALSE; 1843 glyphpath->elemIsQueued = FALSE; 1844 } 1845 } 1846 1847 1848/* END */ 1849