1/***************************************************************************/ 2/* */ 3/* cf2hints.c */ 4/* */ 5/* Adobe's code for handling CFF hints (body). */ 6/* */ 7/* Copyright 2007-2013 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 "../../include/freetype/internal/ftdebug.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 FT_ASSERT( hintmap->isValid ); /* must call Build before Map */ 308 FT_ASSERT( hintmap->lastIndex < CF2_MAX_HINT_EDGES ); 309 310 if ( hintmap->count == 0 || ! hintmap->hinted ) 311 { 312 /* there are no hints; use uniform scale and zero offset */ 313 return FT_MulFix( csCoord, hintmap->scale ); 314 } 315 else 316 { 317 /* start linear search from last hit */ 318 CF2_UInt i = hintmap->lastIndex; 319 320 321 /* search up */ 322 while ( i < hintmap->count - 1 && 323 csCoord >= hintmap->edge[i + 1].csCoord ) 324 i += 1; 325 326 /* search down */ 327 while ( i > 0 && csCoord < hintmap->edge[i].csCoord ) 328 i -= 1; 329 330 hintmap->lastIndex = i; 331 332 if ( i == 0 && csCoord < hintmap->edge[0].csCoord ) 333 { 334 /* special case for points below first edge: use uniform scale */ 335 return FT_MulFix( csCoord - hintmap->edge[0].csCoord, 336 hintmap->scale ) + 337 hintmap->edge[0].dsCoord; 338 } 339 else 340 { 341 /* 342 * Note: entries with duplicate csCoord are allowed. 343 * Use edge[i], the highest entry where csCoord >= entry[i].csCoord 344 */ 345 return FT_MulFix( csCoord - hintmap->edge[i].csCoord, 346 hintmap->edge[i].scale ) + 347 hintmap->edge[i].dsCoord; 348 } 349 } 350 } 351 352 353 /* 354 * This hinting policy moves a hint pair in device space so that one of 355 * its two edges is on a device pixel boundary (its fractional part is 356 * zero). `cf2_hintmap_insertHint' guarantees no overlap in CS 357 * space. Ensure here that there is no overlap in DS. 358 * 359 * In the first pass, edges are adjusted relative to adjacent hints. 360 * Those that are below have already been adjusted. Those that are 361 * above have not yet been adjusted. If a hint above blocks an 362 * adjustment to an optimal position, we will try again in a second 363 * pass. The second pass is top-down. 364 * 365 */ 366 367 static void 368 cf2_hintmap_adjustHints( CF2_HintMap hintmap ) 369 { 370 size_t i, j; 371 372 373 cf2_arrstack_clear( hintmap->hintMoves ); /* working storage */ 374 375 /* 376 * First pass is bottom-up (font hint order) without look-ahead. 377 * Locked edges are already adjusted. 378 * Unlocked edges begin with dsCoord from `initialHintMap'. 379 * Save edges that are not optimally adjusted in `hintMoves' array, 380 * and process them in second pass. 381 */ 382 383 for ( i = 0; i < hintmap->count; i++ ) 384 { 385 FT_Bool isPair = cf2_hint_isPair( &hintmap->edge[i] ); 386 387 388 /* index of upper edge (same value for ghost hint) */ 389 j = isPair ? i + 1 : i; 390 391 FT_ASSERT( j < hintmap->count ); 392 FT_ASSERT( cf2_hint_isValid( &hintmap->edge[i] ) ); 393 FT_ASSERT( cf2_hint_isValid( &hintmap->edge[j] ) ); 394 FT_ASSERT( cf2_hint_isLocked( &hintmap->edge[i] ) == 395 cf2_hint_isLocked( &hintmap->edge[j] ) ); 396 397 if ( !cf2_hint_isLocked( &hintmap->edge[i] ) ) 398 { 399 /* hint edge is not locked, we can adjust it */ 400 CF2_Fixed fracDown = cf2_fixedFraction( hintmap->edge[i].dsCoord ); 401 CF2_Fixed fracUp = cf2_fixedFraction( hintmap->edge[j].dsCoord ); 402 403 /* calculate all four possibilities; moves down are negative */ 404 CF2_Fixed downMoveDown = 0 - fracDown; 405 CF2_Fixed upMoveDown = 0 - fracUp; 406 CF2_Fixed downMoveUp = fracDown == 0 407 ? 0 408 : cf2_intToFixed( 1 ) - fracDown; 409 CF2_Fixed upMoveUp = fracUp == 0 410 ? 0 411 : cf2_intToFixed( 1 ) - fracUp; 412 413 /* smallest move up */ 414 CF2_Fixed moveUp = FT_MIN( downMoveUp, upMoveUp ); 415 /* smallest move down */ 416 CF2_Fixed moveDown = FT_MAX( downMoveDown, upMoveDown ); 417 418 /* final amount to move edge or edge pair */ 419 CF2_Fixed move; 420 421 CF2_Fixed downMinCounter = CF2_MIN_COUNTER; 422 CF2_Fixed upMinCounter = CF2_MIN_COUNTER; 423 FT_Bool saveEdge = FALSE; 424 425 426 /* minimum counter constraint doesn't apply when adjacent edges */ 427 /* are synthetic */ 428 /* TODO: doesn't seem a big effect; for now, reduce the code */ 429#if 0 430 if ( i == 0 || 431 cf2_hint_isSynthetic( &hintmap->edge[i - 1] ) ) 432 downMinCounter = 0; 433 434 if ( j >= hintmap->count - 1 || 435 cf2_hint_isSynthetic( &hintmap->edge[j + 1] ) ) 436 upMinCounter = 0; 437#endif 438 439 /* is there room to move up? */ 440 /* there is if we are at top of array or the next edge is at or */ 441 /* beyond proposed move up? */ 442 if ( j >= hintmap->count - 1 || 443 hintmap->edge[j + 1].dsCoord >= 444 hintmap->edge[j].dsCoord + moveUp + upMinCounter ) 445 { 446 /* there is room to move up; is there also room to move down? */ 447 if ( i == 0 || 448 hintmap->edge[i - 1].dsCoord <= 449 hintmap->edge[i].dsCoord + moveDown - downMinCounter ) 450 { 451 /* move smaller absolute amount */ 452 move = ( -moveDown < moveUp ) ? moveDown : moveUp; /* optimum */ 453 } 454 else 455 move = moveUp; 456 } 457 else 458 { 459 /* is there room to move down? */ 460 if ( i == 0 || 461 hintmap->edge[i - 1].dsCoord <= 462 hintmap->edge[i].dsCoord + moveDown - downMinCounter ) 463 { 464 move = moveDown; 465 /* true if non-optimum move */ 466 saveEdge = (FT_Bool)( moveUp < -moveDown ); 467 } 468 else 469 { 470 /* no room to move either way without overlapping or reducing */ 471 /* the counter too much */ 472 move = 0; 473 saveEdge = TRUE; 474 } 475 } 476 477 /* Identify non-moves and moves down that aren't optimal, and save */ 478 /* them for second pass. */ 479 /* Do this only if there is an unlocked edge above (which could */ 480 /* possibly move). */ 481 if ( saveEdge && 482 j < hintmap->count - 1 && 483 !cf2_hint_isLocked( &hintmap->edge[j + 1] ) ) 484 { 485 CF2_HintMoveRec savedMove; 486 487 488 savedMove.j = j; 489 /* desired adjustment in second pass */ 490 savedMove.moveUp = moveUp - move; 491 492 cf2_arrstack_push( hintmap->hintMoves, &savedMove ); 493 } 494 495 /* move the edge(s) */ 496 hintmap->edge[i].dsCoord += move; 497 if ( isPair ) 498 hintmap->edge[j].dsCoord += move; 499 } 500 501 /* assert there are no overlaps in device space */ 502 FT_ASSERT( i == 0 || 503 hintmap->edge[i - 1].dsCoord <= hintmap->edge[i].dsCoord ); 504 FT_ASSERT( i < j || 505 hintmap->edge[i].dsCoord <= hintmap->edge[j].dsCoord ); 506 507 /* adjust the scales, avoiding divide by zero */ 508 if ( i > 0 ) 509 { 510 if ( hintmap->edge[i].csCoord != hintmap->edge[i - 1].csCoord ) 511 hintmap->edge[i - 1].scale = 512 FT_DivFix( 513 hintmap->edge[i].dsCoord - hintmap->edge[i - 1].dsCoord, 514 hintmap->edge[i].csCoord - hintmap->edge[i - 1].csCoord ); 515 } 516 517 if ( isPair ) 518 { 519 if ( hintmap->edge[j].csCoord != hintmap->edge[j - 1].csCoord ) 520 hintmap->edge[j - 1].scale = 521 FT_DivFix( 522 hintmap->edge[j].dsCoord - hintmap->edge[j - 1].dsCoord, 523 hintmap->edge[j].csCoord - hintmap->edge[j - 1].csCoord ); 524 525 i += 1; /* skip upper edge on next loop */ 526 } 527 } 528 529 /* second pass tries to move non-optimal hints up, in case there is */ 530 /* room now */ 531 for ( i = cf2_arrstack_size( hintmap->hintMoves ); i > 0; i-- ) 532 { 533 CF2_HintMove hintMove = (CF2_HintMove) 534 cf2_arrstack_getPointer( hintmap->hintMoves, i - 1 ); 535 536 537 j = hintMove->j; 538 539 /* this was tested before the push, above */ 540 FT_ASSERT( j < hintmap->count - 1 ); 541 542 /* is there room to move up? */ 543 if ( hintmap->edge[j + 1].dsCoord >= 544 hintmap->edge[j].dsCoord + hintMove->moveUp + CF2_MIN_COUNTER ) 545 { 546 /* there is more room now, move edge up */ 547 hintmap->edge[j].dsCoord += hintMove->moveUp; 548 549 if ( cf2_hint_isPair( &hintmap->edge[j] ) ) 550 { 551 FT_ASSERT( j > 0 ); 552 hintmap->edge[j - 1].dsCoord += hintMove->moveUp; 553 } 554 } 555 } 556 } 557 558 559 /* insert hint edges into map, sorted by csCoord */ 560 static void 561 cf2_hintmap_insertHint( CF2_HintMap hintmap, 562 CF2_Hint bottomHintEdge, 563 CF2_Hint topHintEdge ) 564 { 565 CF2_UInt indexInsert; 566 567 /* set default values, then check for edge hints */ 568 FT_Bool isPair = TRUE; 569 CF2_Hint firstHintEdge = bottomHintEdge; 570 CF2_Hint secondHintEdge = topHintEdge; 571 572 573 /* one or none of the input params may be invalid when dealing with */ 574 /* edge hints; at least one edge must be valid */ 575 FT_ASSERT( cf2_hint_isValid( bottomHintEdge ) || 576 cf2_hint_isValid( topHintEdge ) ); 577 578 /* determine how many and which edges to insert */ 579 if ( !cf2_hint_isValid( bottomHintEdge ) ) 580 { 581 /* insert only the top edge */ 582 firstHintEdge = topHintEdge; 583 isPair = FALSE; 584 } 585 else if ( !cf2_hint_isValid( topHintEdge ) ) 586 { 587 /* insert only the bottom edge */ 588 isPair = FALSE; 589 } 590 591 /* paired edges must be in proper order */ 592 FT_ASSERT( !isPair || 593 topHintEdge->csCoord >= bottomHintEdge->csCoord ); 594 595 /* linear search to find index value of insertion point */ 596 indexInsert = 0; 597 for ( ; indexInsert < hintmap->count; indexInsert++ ) 598 { 599 if ( hintmap->edge[indexInsert].csCoord > firstHintEdge->csCoord ) 600 break; 601 } 602 603 /* 604 * Discard any hints that overlap in character space. Most often, 605 * this is while building the initial map, but in theory, it can also 606 * occur because of darkening. 607 * 608 */ 609 if ( indexInsert < hintmap->count ) 610 { 611 /* we are inserting before an existing edge: */ 612 /* verify that a new pair does not straddle the next edge */ 613 if ( isPair && 614 hintmap->edge[indexInsert].csCoord < secondHintEdge->csCoord ) 615 return; /* ignore overlapping stem hint */ 616 617 /* verify that we are not inserting between paired edges */ 618 if ( cf2_hint_isPairTop( &hintmap->edge[indexInsert] ) ) 619 return; /* ignore overlapping stem hint */ 620 } 621 622 /* recompute device space locations using initial hint map */ 623 if ( cf2_hintmap_isValid( hintmap->initialHintMap ) && 624 !cf2_hint_isLocked( firstHintEdge ) ) 625 { 626 if ( isPair ) 627 { 628 /* Use hint map to position the center of stem, and nominal scale */ 629 /* to position the two edges. This preserves the stem width. */ 630 CF2_Fixed midpoint = cf2_hintmap_map( 631 hintmap->initialHintMap, 632 ( secondHintEdge->csCoord + 633 firstHintEdge->csCoord ) / 2 ); 634 CF2_Fixed halfWidth = FT_MulFix( 635 ( secondHintEdge->csCoord - 636 firstHintEdge->csCoord ) / 2, 637 hintmap->scale ); 638 639 640 firstHintEdge->dsCoord = midpoint - halfWidth; 641 secondHintEdge->dsCoord = midpoint + halfWidth; 642 } 643 else 644 firstHintEdge->dsCoord = cf2_hintmap_map( hintmap->initialHintMap, 645 firstHintEdge->csCoord ); 646 } 647 648 /* discard any hints that overlap in device space; this can occur */ 649 /* because locked hints have been moved to align with blue zones */ 650 if ( indexInsert > 0 ) 651 { 652 /* we are inserting after an existing edge */ 653 if ( firstHintEdge->dsCoord < hintmap->edge[indexInsert - 1].dsCoord ) 654 return; 655 } 656 657 if ( indexInsert < hintmap->count ) 658 { 659 /* we are inserting before an existing edge */ 660 if ( isPair ) 661 { 662 if ( secondHintEdge->dsCoord > hintmap->edge[indexInsert].dsCoord ) 663 return; 664 } 665 else 666 { 667 if ( firstHintEdge->dsCoord > hintmap->edge[indexInsert].dsCoord ) 668 return; 669 } 670 } 671 672 /* make room to insert */ 673 { 674 CF2_Int iSrc = hintmap->count - 1; 675 CF2_Int iDst = isPair ? hintmap->count + 1 : hintmap->count; 676 677 CF2_Int count = hintmap->count - indexInsert; 678 679 680 if ( iDst >= CF2_MAX_HINT_EDGES ) 681 { 682 FT_TRACE4(( "cf2_hintmap_insertHint: too many hintmaps\n" )); 683 return; 684 } 685 686 while ( count-- ) 687 hintmap->edge[iDst--] = hintmap->edge[iSrc--]; 688 689 /* insert first edge */ 690 hintmap->edge[indexInsert] = *firstHintEdge; /* copy struct */ 691 hintmap->count += 1; 692 693 if ( isPair ) 694 { 695 /* insert second edge */ 696 hintmap->edge[indexInsert + 1] = *secondHintEdge; /* copy struct */ 697 hintmap->count += 1; 698 } 699 } 700 701 return; 702 } 703 704 705 /* 706 * Build a map from hints and mask. 707 * 708 * This function may recur one level if `hintmap->initialHintMap' is not yet 709 * valid. 710 * If `initialMap' is true, simply build initial map. 711 * 712 * Synthetic hints are used in two ways. A hint at zero is inserted, if 713 * needed, in the initial hint map, to prevent translations from 714 * propagating across the origin. If synthetic em box hints are enabled 715 * for ideographic dictionaries, then they are inserted in all hint 716 * maps, including the initial one. 717 * 718 */ 719 FT_LOCAL_DEF( void ) 720 cf2_hintmap_build( CF2_HintMap hintmap, 721 CF2_ArrStack hStemHintArray, 722 CF2_ArrStack vStemHintArray, 723 CF2_HintMask hintMask, 724 CF2_Fixed hintOrigin, 725 FT_Bool initialMap ) 726 { 727 FT_Byte* maskPtr; 728 FT_Byte* maskEndPtr; // add by Xiaochuan_Liu 729 730 CF2_Font font = hintmap->font; 731 CF2_HintMaskRec tempHintMask; 732 733 size_t bitCount, i; 734 FT_Byte maskByte; 735 736 737 /* check whether initial map is constructed */ 738 if ( !initialMap && !cf2_hintmap_isValid( hintmap->initialHintMap ) ) 739 { 740 /* make recursive call with initialHintMap and temporary mask; */ 741 /* temporary mask will get all bits set, below */ 742 cf2_hintmask_init( &tempHintMask, hintMask->error ); 743 cf2_hintmap_build( hintmap->initialHintMap, 744 hStemHintArray, 745 vStemHintArray, 746 &tempHintMask, 747 hintOrigin, 748 TRUE ); 749 } 750 751 if ( !cf2_hintmask_isValid( hintMask ) ) 752 { 753 /* without a hint mask, assume all hints are active */ 754 cf2_hintmask_setAll( hintMask, 755 cf2_arrstack_size( hStemHintArray ) + 756 cf2_arrstack_size( vStemHintArray ) ); 757 } 758 759 /* begin by clearing the map */ 760 hintmap->count = 0; 761 hintmap->lastIndex = 0; 762 763 /* make a copy of the hint mask so we can modify it */ 764 tempHintMask = *hintMask; 765 maskPtr = cf2_hintmask_getMaskPtr( &tempHintMask ); 766 maskEndPtr = maskPtr + ( CF2_MAX_HINTS + 7 ) / 8; 767 768 769 /* use the hStem hints only, which are first in the mask */ 770 /* TODO: compare this to cffhintmaskGetBitCount */ 771 bitCount = cf2_arrstack_size( hStemHintArray ); 772 773 /* synthetic embox hints get highest priority */ 774 if ( font->blues.doEmBoxHints ) 775 { 776 CF2_HintRec dummy; 777 778 779 cf2_hint_initZero( &dummy ); /* invalid hint map element */ 780 781 /* ghost bottom */ 782 cf2_hintmap_insertHint( hintmap, 783 &font->blues.emBoxBottomEdge, 784 &dummy ); 785 /* ghost top */ 786 cf2_hintmap_insertHint( hintmap, 787 &dummy, 788 &font->blues.emBoxTopEdge ); 789 } 790 791 /* insert hints captured by a blue zone or already locked (higher */ 792 /* priority) */ 793 for ( i = 0, maskByte = 0x80; i < bitCount; i++ ) 794 { 795 if ( maskByte & *maskPtr ) 796 { 797 /* expand StemHint into two `CF2_Hint' elements */ 798 CF2_HintRec bottomHintEdge, topHintEdge; 799 800 801 cf2_hint_init( &bottomHintEdge, 802 hStemHintArray, 803 i, 804 font, 805 hintOrigin, 806 hintmap->scale, 807 TRUE /* bottom */ ); 808 cf2_hint_init( &topHintEdge, 809 hStemHintArray, 810 i, 811 font, 812 hintOrigin, 813 hintmap->scale, 814 FALSE /* top */ ); 815 816 if ( cf2_hint_isLocked( &bottomHintEdge ) || 817 cf2_hint_isLocked( &topHintEdge ) || 818 cf2_blues_capture( &font->blues, 819 &bottomHintEdge, 820 &topHintEdge ) ) 821 { 822 /* insert captured hint into map */ 823 cf2_hintmap_insertHint( hintmap, &bottomHintEdge, &topHintEdge ); 824 825 *maskPtr &= ~maskByte; /* turn off the bit for this hint */ 826 } 827 } 828 829 if ( ( i & 7 ) == 7 ) 830 { 831 /* move to next mask byte */ 832 maskPtr++; 833 if (maskPtr >= maskEndPtr) 834 { 835 break; 836 } 837 838 maskByte = 0x80; 839 } 840 else 841 maskByte >>= 1; 842 } 843 844 /* initial hint map includes only captured hints plus maybe one at 0 */ 845 846 /* 847 * TODO: There is a problem here because we are trying to build a 848 * single hint map containing all captured hints. It is 849 * possible for there to be conflicts between captured hints, 850 * either because of darkening or because the hints are in 851 * separate hint zones (we are ignoring hint zones for the 852 * initial map). An example of the latter is MinionPro-Regular 853 * v2.030 glyph 883 (Greek Capital Alpha with Psili) at 15ppem. 854 * A stem hint for the psili conflicts with the top edge hint 855 * for the base character. The stem hint gets priority because 856 * of its sort order. In glyph 884 (Greek Capital Alpha with 857 * Psili and Oxia), the top of the base character gets a stem 858 * hint, and the psili does not. This creates different initial 859 * maps for the two glyphs resulting in different renderings of 860 * the base character. Will probably defer this either as not 861 * worth the cost or as a font bug. I don't think there is any 862 * good reason for an accent to be captured by an alignment 863 * zone. -darnold 2/12/10 864 */ 865 866 if ( initialMap ) 867 { 868 /* Apply a heuristic that inserts a point for (0,0), unless it's */ 869 /* already covered by a mapping. This locks the baseline for glyphs */ 870 /* that have no baseline hints. */ 871 872 if ( hintmap->count == 0 || 873 hintmap->edge[0].csCoord > 0 || 874 hintmap->edge[hintmap->count - 1].csCoord < 0 ) 875 { 876 /* all edges are above 0 or all edges are below 0; */ 877 /* construct a locked edge hint at 0 */ 878 879 CF2_HintRec edge, invalid; 880 881 882 cf2_hint_initZero( &edge ); 883 884 edge.flags = CF2_GhostBottom | 885 CF2_Locked | 886 CF2_Synthetic; 887 edge.scale = hintmap->scale; 888 889 cf2_hint_initZero( &invalid ); 890 cf2_hintmap_insertHint( hintmap, &edge, &invalid ); 891 } 892 } 893 else 894 { 895 /* insert remaining hints */ 896 897 maskPtr = cf2_hintmask_getMaskPtr( &tempHintMask ); 898 maskEndPtr = maskPtr + ( CF2_MAX_HINTS + 7 ) / 8; 899 900 for ( i = 0, maskByte = 0x80; i < bitCount; i++ ) 901 { 902 if ( maskByte & *maskPtr ) 903 { 904 CF2_HintRec bottomHintEdge, topHintEdge; 905 906 907 cf2_hint_init( &bottomHintEdge, 908 hStemHintArray, 909 i, 910 font, 911 hintOrigin, 912 hintmap->scale, 913 TRUE /* bottom */ ); 914 cf2_hint_init( &topHintEdge, 915 hStemHintArray, 916 i, 917 font, 918 hintOrigin, 919 hintmap->scale, 920 FALSE /* top */ ); 921 922 cf2_hintmap_insertHint( hintmap, &bottomHintEdge, &topHintEdge ); 923 } 924 925 if ( ( i & 7 ) == 7 ) 926 { 927 /* move to next mask byte */ 928 maskPtr++; 929 if (maskPtr >= maskEndPtr) 930 { 931 break; 932 } 933 maskByte = 0x80; 934 } 935 else 936 maskByte >>= 1; 937 } 938 } 939 940 /* 941 * Note: The following line is a convenient place to break when 942 * debugging hinting. Examine `hintmap->edge' for the list of 943 * enabled hints, then step over the call to see the effect of 944 * adjustment. We stop here first on the recursive call that 945 * creates the initial map, and then on each counter group and 946 * hint zone. 947 */ 948 949 /* adjust positions of hint edges that are not locked to blue zones */ 950 cf2_hintmap_adjustHints( hintmap ); 951 952 /* save the position of all hints that were used in this hint map; */ 953 /* if we use them again, we'll locate them in the same position */ 954 if ( !initialMap ) 955 { 956 for ( i = 0; i < hintmap->count; i++ ) 957 { 958 if ( !cf2_hint_isSynthetic( &hintmap->edge[i] ) ) 959 { 960 /* Note: include both valid and invalid edges */ 961 /* Note: top and bottom edges are copied back separately */ 962 CF2_StemHint stemhint = (CF2_StemHint) 963 cf2_arrstack_getPointer( hStemHintArray, 964 hintmap->edge[i].index ); 965 966 967 if ( cf2_hint_isTop( &hintmap->edge[i] ) ) 968 stemhint->maxDS = hintmap->edge[i].dsCoord; 969 else 970 stemhint->minDS = hintmap->edge[i].dsCoord; 971 972 stemhint->used = TRUE; 973 } 974 } 975 } 976 977 /* hint map is ready to use */ 978 hintmap->isValid = TRUE; 979 980 /* remember this mask has been used */ 981 cf2_hintmask_setNew( hintMask, FALSE ); 982 } 983 984 985 FT_LOCAL_DEF( void ) 986 cf2_glyphpath_init( CF2_GlyphPath glyphpath, 987 CF2_Font font, 988 CF2_OutlineCallbacks callbacks, 989 CF2_Fixed scaleY, 990 /* CF2_Fixed hShift, */ 991 CF2_ArrStack hStemHintArray, 992 CF2_ArrStack vStemHintArray, 993 CF2_HintMask hintMask, 994 CF2_Fixed hintOriginY, 995 const CF2_Blues blues, 996 const FT_Vector* fractionalTranslation ) 997 { 998 FT_ZERO( glyphpath ); 999 1000 glyphpath->font = font; 1001 glyphpath->callbacks = callbacks; 1002 1003 cf2_arrstack_init( &glyphpath->hintMoves, 1004 font->memory, 1005 &font->error, 1006 sizeof ( CF2_HintMoveRec ) ); 1007 1008 cf2_hintmap_init( &glyphpath->initialHintMap, 1009 font, 1010 &glyphpath->initialHintMap, 1011 &glyphpath->hintMoves, 1012 scaleY ); 1013 cf2_hintmap_init( &glyphpath->firstHintMap, 1014 font, 1015 &glyphpath->initialHintMap, 1016 &glyphpath->hintMoves, 1017 scaleY ); 1018 cf2_hintmap_init( &glyphpath->hintMap, 1019 font, 1020 &glyphpath->initialHintMap, 1021 &glyphpath->hintMoves, 1022 scaleY ); 1023 1024 glyphpath->scaleX = font->innerTransform.a; 1025 glyphpath->scaleC = font->innerTransform.c; 1026 glyphpath->scaleY = font->innerTransform.d; 1027 1028 glyphpath->fractionalTranslation = *fractionalTranslation; 1029 1030#if 0 1031 glyphpath->hShift = hShift; /* for fauxing */ 1032#endif 1033 1034 glyphpath->hStemHintArray = hStemHintArray; 1035 glyphpath->vStemHintArray = vStemHintArray; 1036 glyphpath->hintMask = hintMask; /* ptr to current mask */ 1037 glyphpath->hintOriginY = hintOriginY; 1038 glyphpath->blues = blues; 1039 glyphpath->darken = font->darkened; /* TODO: should we make copies? */ 1040 glyphpath->xOffset = font->darkenX; 1041 glyphpath->yOffset = font->darkenY; 1042 glyphpath->miterLimit = 2 * FT_MAX( 1043 cf2_fixedAbs( glyphpath->xOffset ), 1044 cf2_fixedAbs( glyphpath->yOffset ) ); 1045 1046 /* .1 character space unit */ 1047 glyphpath->snapThreshold = cf2_floatToFixed( 0.1f ); 1048 1049 glyphpath->moveIsPending = TRUE; 1050 glyphpath->pathIsOpen = FALSE; 1051 glyphpath->elemIsQueued = FALSE; 1052 } 1053 1054 1055 FT_LOCAL_DEF( void ) 1056 cf2_glyphpath_finalize( CF2_GlyphPath glyphpath ) 1057 { 1058 cf2_arrstack_finalize( &glyphpath->hintMoves ); 1059 } 1060 1061 1062 /* 1063 * Hint point in y-direction and apply outerTransform. 1064 * Input `current' hint map (which is actually delayed by one element). 1065 * Input x,y point in Character Space. 1066 * Output x,y point in Device Space, including translation. 1067 */ 1068 static void 1069 cf2_glyphpath_hintPoint( CF2_GlyphPath glyphpath, 1070 CF2_HintMap hintmap, 1071 FT_Vector* ppt, 1072 CF2_Fixed x, 1073 CF2_Fixed y ) 1074 { 1075 FT_Vector pt; /* hinted point in upright DS */ 1076 1077 1078 pt.x = FT_MulFix( glyphpath->scaleX, x ) + 1079 FT_MulFix( glyphpath->scaleC, y ); 1080 pt.y = cf2_hintmap_map( hintmap, y ); 1081 1082 ppt->x = FT_MulFix( glyphpath->font->outerTransform.a, pt.x ) + 1083 FT_MulFix( glyphpath->font->outerTransform.c, pt.y ) + 1084 glyphpath->fractionalTranslation.x; 1085 ppt->y = FT_MulFix( glyphpath->font->outerTransform.b, pt.x ) + 1086 FT_MulFix( glyphpath->font->outerTransform.d, pt.y ) + 1087 glyphpath->fractionalTranslation.y; 1088 } 1089 1090 1091 /* 1092 * From two line segments, (u1,u2) and (v1,v2), compute a point of 1093 * intersection on the corresponding lines. 1094 * Return false if no intersection is found, or if the intersection is 1095 * too far away from the ends of the line segments, u2 and v1. 1096 * 1097 */ 1098 static FT_Bool 1099 cf2_glyphpath_computeIntersection( CF2_GlyphPath glyphpath, 1100 const FT_Vector* u1, 1101 const FT_Vector* u2, 1102 const FT_Vector* v1, 1103 const FT_Vector* v2, 1104 FT_Vector* intersection ) 1105 { 1106 /* 1107 * Let `u' be a zero-based vector from the first segment, `v' from the 1108 * second segment. 1109 * Let `w 'be the zero-based vector from `u1' to `v1'. 1110 * `perp' is the `perpendicular dot product'; see 1111 * http://mathworld.wolfram.com/PerpDotProduct.html. 1112 * `s' is the parameter for the parametric line for the first segment 1113 * (`u'). 1114 * 1115 * See notation in 1116 * http://softsurfer.com/Archive/algorithm_0104/algorithm_0104B.htm. 1117 * Calculations are done in 16.16, but must handle the squaring of 1118 * line lengths in character space. We scale all vectors by 1/32 to 1119 * avoid overflow. This allows values up to 4095 to be squared. The 1120 * scale factor cancels in the divide. 1121 * 1122 * TODO: the scale factor could be computed from UnitsPerEm. 1123 * 1124 */ 1125 1126#define cf2_perp( a, b ) \ 1127 ( FT_MulFix( a.x, b.y ) - FT_MulFix( a.y, b.x ) ) 1128 1129 /* round and divide by 32 */ 1130#define CF2_CS_SCALE( x ) \ 1131 ( ( (x) + 0x10 ) >> 5 ) 1132 1133 FT_Vector u, v, w; /* scaled vectors */ 1134 CF2_Fixed denominator, s; 1135 1136 1137 u.x = CF2_CS_SCALE( u2->x - u1->x ); 1138 u.y = CF2_CS_SCALE( u2->y - u1->y ); 1139 v.x = CF2_CS_SCALE( v2->x - v1->x ); 1140 v.y = CF2_CS_SCALE( v2->y - v1->y ); 1141 w.x = CF2_CS_SCALE( v1->x - u1->x ); 1142 w.y = CF2_CS_SCALE( v1->y - u1->y ); 1143 1144 denominator = cf2_perp( u, v ); 1145 1146 if ( denominator == 0 ) 1147 return FALSE; /* parallel or coincident lines */ 1148 1149 s = FT_DivFix( cf2_perp( w, v ), denominator ); 1150 1151 intersection->x = u1->x + FT_MulFix( s, u2->x - u1->x ); 1152 intersection->y = u1->y + FT_MulFix( s, u2->y - u1->y ); 1153 1154 /* 1155 * Special case snapping for horizontal and vertical lines. 1156 * This cleans up intersections and reduces problems with winding 1157 * order detection. 1158 * Sample case is sbc cd KozGoPr6N-Medium.otf 20 16685. 1159 * Note: these calculations are in character space. 1160 * 1161 */ 1162 1163 if ( u1->x == u2->x && 1164 cf2_fixedAbs( intersection->x - u1->x ) < glyphpath->snapThreshold ) 1165 intersection->x = u1->x; 1166 if ( u1->y == u2->y && 1167 cf2_fixedAbs( intersection->y - u1->y ) < glyphpath->snapThreshold ) 1168 intersection->y = u1->y; 1169 1170 if ( v1->x == v2->x && 1171 cf2_fixedAbs( intersection->x - v1->x ) < glyphpath->snapThreshold ) 1172 intersection->x = v1->x; 1173 if ( v1->y == v2->y && 1174 cf2_fixedAbs( intersection->y - v1->y ) < glyphpath->snapThreshold ) 1175 intersection->y = v1->y; 1176 1177 /* limit the intersection distance from midpoint of u2 and v1 */ 1178 if ( cf2_fixedAbs( intersection->x - ( u2->x + v1->x ) / 2 ) > 1179 glyphpath->miterLimit || 1180 cf2_fixedAbs( intersection->y - ( u2->y + v1->y ) / 2 ) > 1181 glyphpath->miterLimit ) 1182 return FALSE; 1183 1184 return TRUE; 1185 } 1186 1187 1188 /* 1189 * Push the cached element (glyphpath->prevElem*) to the outline 1190 * consumer. When a darkening offset is used, the end point of the 1191 * cached element may be adjusted to an intersection point or it may be 1192 * connected by a line to the current element. This calculation must 1193 * use a HintMap that was valid at the time the element was saved. For 1194 * the first point in a subpath, that is a saved HintMap. For most 1195 * elements, it just means the caller has delayed building a HintMap 1196 * from the current HintMask. 1197 * 1198 * Transform each point with outerTransform and call the outline 1199 * callbacks. This is a general 3x3 transform: 1200 * 1201 * x' = a*x + c*y + tx, y' = b*x + d*y + ty 1202 * 1203 * but it uses 4 elements from CF2_Font and the translation part 1204 * from CF2_GlyphPath. 1205 * 1206 */ 1207 static void 1208 cf2_glyphpath_pushPrevElem( CF2_GlyphPath glyphpath, 1209 CF2_HintMap hintmap, 1210 FT_Vector* nextP0, 1211 FT_Vector nextP1, 1212 FT_Bool close ) 1213 { 1214 CF2_CallbackParamsRec params; 1215 1216 FT_Vector* prevP0; 1217 FT_Vector* prevP1; 1218 1219 FT_Vector intersection = { 0, 0 }; 1220 FT_Bool useIntersection = FALSE; 1221 1222 1223 FT_ASSERT( glyphpath->prevElemOp == CF2_PathOpLineTo || 1224 glyphpath->prevElemOp == CF2_PathOpCubeTo ); 1225 1226 if ( glyphpath->prevElemOp == CF2_PathOpLineTo ) 1227 { 1228 prevP0 = &glyphpath->prevElemP0; 1229 prevP1 = &glyphpath->prevElemP1; 1230 } 1231 else 1232 { 1233 prevP0 = &glyphpath->prevElemP2; 1234 prevP1 = &glyphpath->prevElemP3; 1235 } 1236 1237 /* optimization: if previous and next elements are offset by the same */ 1238 /* amount, then there will be no gap, and no need to compute an */ 1239 /* intersection. */ 1240 if ( prevP1->x != nextP0->x || prevP1->y != nextP0->y ) 1241 { 1242 /* previous element does not join next element: */ 1243 /* adjust end point of previous element to the intersection */ 1244 useIntersection = cf2_glyphpath_computeIntersection( glyphpath, 1245 prevP0, 1246 prevP1, 1247 nextP0, 1248 &nextP1, 1249 &intersection ); 1250 if ( useIntersection ) 1251 { 1252 /* modify the last point of the cached element (either line or */ 1253 /* curve) */ 1254 *prevP1 = intersection; 1255 } 1256 } 1257 1258 params.pt0 = glyphpath->currentDS; 1259 1260 switch( glyphpath->prevElemOp ) 1261 { 1262 case CF2_PathOpLineTo: 1263 params.op = CF2_PathOpLineTo; 1264 1265 /* note: pt2 and pt3 are unused */ 1266 cf2_glyphpath_hintPoint( glyphpath, 1267 hintmap, 1268 ¶ms.pt1, 1269 glyphpath->prevElemP1.x, 1270 glyphpath->prevElemP1.y ); 1271 1272 glyphpath->callbacks->lineTo( glyphpath->callbacks, ¶ms ); 1273 1274 glyphpath->currentDS = params.pt1; 1275 1276 break; 1277 1278 case CF2_PathOpCubeTo: 1279 params.op = CF2_PathOpCubeTo; 1280 1281 /* TODO: should we intersect the interior joins (p1-p2 and p2-p3)? */ 1282 cf2_glyphpath_hintPoint( glyphpath, 1283 hintmap, 1284 ¶ms.pt1, 1285 glyphpath->prevElemP1.x, 1286 glyphpath->prevElemP1.y ); 1287 cf2_glyphpath_hintPoint( glyphpath, 1288 hintmap, 1289 ¶ms.pt2, 1290 glyphpath->prevElemP2.x, 1291 glyphpath->prevElemP2.y ); 1292 cf2_glyphpath_hintPoint( glyphpath, 1293 hintmap, 1294 ¶ms.pt3, 1295 glyphpath->prevElemP3.x, 1296 glyphpath->prevElemP3.y ); 1297 1298 glyphpath->callbacks->cubeTo( glyphpath->callbacks, ¶ms ); 1299 1300 glyphpath->currentDS = params.pt3; 1301 1302 break; 1303 } 1304 1305 if ( !useIntersection || close ) 1306 { 1307 /* insert connecting line between end of previous element and start */ 1308 /* of current one */ 1309 /* note: at the end of a subpath, we might do both, so use `nextP0' */ 1310 /* before we change it, below */ 1311 1312 cf2_glyphpath_hintPoint( glyphpath, 1313 hintmap, 1314 ¶ms.pt1, 1315 nextP0->x, 1316 nextP0->y ); 1317 1318 if ( params.pt1.x != glyphpath->currentDS.x || 1319 params.pt1.y != glyphpath->currentDS.y ) 1320 { 1321 /* length is nonzero */ 1322 params.op = CF2_PathOpLineTo; 1323 params.pt0 = glyphpath->currentDS; 1324 1325 /* note: pt2 and pt3 are unused */ 1326 glyphpath->callbacks->lineTo( glyphpath->callbacks, ¶ms ); 1327 1328 glyphpath->currentDS = params.pt1; 1329 } 1330 } 1331 1332 if ( useIntersection ) 1333 { 1334 /* return intersection point to caller */ 1335 *nextP0 = intersection; 1336 } 1337 } 1338 1339 1340 /* push a MoveTo element based on current point and offset of current */ 1341 /* element */ 1342 static void 1343 cf2_glyphpath_pushMove( CF2_GlyphPath glyphpath, 1344 FT_Vector start ) 1345 { 1346 CF2_CallbackParamsRec params; 1347 1348 1349 params.op = CF2_PathOpMoveTo; 1350 params.pt0 = glyphpath->currentDS; 1351 1352 /* Test if move has really happened yet; it would have called */ 1353 /* `cf2_hintmap_build' to set `isValid'. */ 1354 if ( !cf2_hintmap_isValid( &glyphpath->hintMap ) ) 1355 { 1356 /* we are here iff first subpath is missing a moveto operator: */ 1357 /* synthesize first moveTo to finish initialization of hintMap */ 1358 cf2_glyphpath_moveTo( glyphpath, 1359 glyphpath->start.x, 1360 glyphpath->start.y ); 1361 } 1362 1363 cf2_glyphpath_hintPoint( glyphpath, 1364 &glyphpath->hintMap, 1365 ¶ms.pt1, 1366 start.x, 1367 start.y ); 1368 1369 /* note: pt2 and pt3 are unused */ 1370 glyphpath->callbacks->moveTo( glyphpath->callbacks, ¶ms ); 1371 1372 glyphpath->currentDS = params.pt1; 1373 glyphpath->offsetStart0 = start; 1374 } 1375 1376 1377 /* 1378 * All coordinates are in character space. 1379 * On input, (x1, y1) and (x2, y2) give line segment. 1380 * On output, (x, y) give offset vector. 1381 * We use a piecewise approximation to trig functions. 1382 * 1383 * TODO: Offset true perpendicular and proper length 1384 * supply the y-translation for hinting here, too, 1385 * that adds yOffset unconditionally to *y. 1386 */ 1387 static void 1388 cf2_glyphpath_computeOffset( CF2_GlyphPath glyphpath, 1389 CF2_Fixed x1, 1390 CF2_Fixed y1, 1391 CF2_Fixed x2, 1392 CF2_Fixed y2, 1393 CF2_Fixed* x, 1394 CF2_Fixed* y ) 1395 { 1396 CF2_Fixed dx = x2 - x1; 1397 CF2_Fixed dy = y2 - y1; 1398 1399 1400 /* note: negative offsets don't work here; negate deltas to change */ 1401 /* quadrants, below */ 1402 if ( glyphpath->font->reverseWinding ) 1403 { 1404 dx = -dx; 1405 dy = -dy; 1406 } 1407 1408 *x = *y = 0; 1409 1410 if ( !glyphpath->darken ) 1411 return; 1412 1413 /* add momentum for this path element */ 1414 glyphpath->callbacks->windingMomentum += 1415 cf2_getWindingMomentum( x1, y1, x2, y2 ); 1416 1417 /* note: allow mixed integer and fixed multiplication here */ 1418 if ( dx >= 0 ) 1419 { 1420 if ( dy >= 0 ) 1421 { 1422 /* first quadrant, +x +y */ 1423 1424 if ( dx > 2 * dy ) 1425 { 1426 /* +x */ 1427 *x = 0; 1428 *y = 0; 1429 } 1430 else if ( dy > 2 * dx ) 1431 { 1432 /* +y */ 1433 *x = glyphpath->xOffset; 1434 *y = glyphpath->yOffset; 1435 } 1436 else 1437 { 1438 /* +x +y */ 1439 *x = FT_MulFix( cf2_floatToFixed( 0.7 ), 1440 glyphpath->xOffset ); 1441 *y = FT_MulFix( cf2_floatToFixed( 1.0 - 0.7 ), 1442 glyphpath->yOffset ); 1443 } 1444 } 1445 else 1446 { 1447 /* fourth quadrant, +x -y */ 1448 1449 if ( dx > -2 * dy ) 1450 { 1451 /* +x */ 1452 *x = 0; 1453 *y = 0; 1454 } 1455 else if ( -dy > 2 * dx ) 1456 { 1457 /* -y */ 1458 *x = -glyphpath->xOffset; 1459 *y = glyphpath->yOffset; 1460 } 1461 else 1462 { 1463 /* +x -y */ 1464 *x = FT_MulFix( cf2_floatToFixed( -0.7 ), 1465 glyphpath->xOffset ); 1466 *y = FT_MulFix( cf2_floatToFixed( 1.0 - 0.7 ), 1467 glyphpath->yOffset ); 1468 } 1469 } 1470 } 1471 else 1472 { 1473 if ( dy >= 0 ) 1474 { 1475 /* second quadrant, -x +y */ 1476 1477 if ( -dx > 2 * dy ) 1478 { 1479 /* -x */ 1480 *x = 0; 1481 *y = 2 * glyphpath->yOffset; 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 /* third quadrant, -x -y */ 1501 1502 if ( -dx > -2 * dy ) 1503 { 1504 /* -x */ 1505 *x = 0; 1506 *y = 2 * glyphpath->yOffset; 1507 } 1508 else if ( -dy > -2 * dx ) 1509 { 1510 /* -y */ 1511 *x = -glyphpath->xOffset; 1512 *y = glyphpath->xOffset; 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 } 1525 1526 1527 FT_LOCAL_DEF( void ) 1528 cf2_glyphpath_moveTo( CF2_GlyphPath glyphpath, 1529 CF2_Fixed x, 1530 CF2_Fixed y ) 1531 { 1532 cf2_glyphpath_closeOpenPath( glyphpath ); 1533 1534 /* save the parameters of the move for later, when we'll know how to */ 1535 /* offset it; */ 1536 /* also save last move point */ 1537 glyphpath->currentCS.x = glyphpath->start.x = x; 1538 glyphpath->currentCS.y = glyphpath->start.y = y; 1539 1540 glyphpath->moveIsPending = TRUE; 1541 1542 /* ensure we have a valid map with current mask */ 1543 if ( !cf2_hintmap_isValid( &glyphpath->hintMap ) || 1544 cf2_hintmask_isNew( glyphpath->hintMask ) ) 1545 cf2_hintmap_build( &glyphpath->hintMap, 1546 glyphpath->hStemHintArray, 1547 glyphpath->vStemHintArray, 1548 glyphpath->hintMask, 1549 glyphpath->hintOriginY, 1550 FALSE ); 1551 1552 /* save a copy of current HintMap to use when drawing initial point */ 1553 glyphpath->firstHintMap = glyphpath->hintMap; /* structure copy */ 1554 } 1555 1556 1557 FT_LOCAL_DEF( void ) 1558 cf2_glyphpath_lineTo( CF2_GlyphPath glyphpath, 1559 CF2_Fixed x, 1560 CF2_Fixed y ) 1561 { 1562 CF2_Fixed xOffset, yOffset; 1563 FT_Vector P0, P1; 1564 1565 1566 /* can't compute offset of zero length line, so ignore them */ 1567 if ( glyphpath->currentCS.x == x && glyphpath->currentCS.y == y ) 1568 return; 1569 1570 cf2_glyphpath_computeOffset( glyphpath, 1571 glyphpath->currentCS.x, 1572 glyphpath->currentCS.y, 1573 x, 1574 y, 1575 &xOffset, 1576 &yOffset ); 1577 1578 /* construct offset points */ 1579 P0.x = glyphpath->currentCS.x + xOffset; 1580 P0.y = glyphpath->currentCS.y + yOffset; 1581 P1.x = x + xOffset; 1582 P1.y = y + yOffset; 1583 1584 if ( glyphpath->moveIsPending ) 1585 { 1586 /* emit offset 1st point as MoveTo */ 1587 cf2_glyphpath_pushMove( glyphpath, P0 ); 1588 1589 glyphpath->moveIsPending = FALSE; /* adjust state machine */ 1590 glyphpath->pathIsOpen = TRUE; 1591 1592 glyphpath->offsetStart1 = P1; /* record second point */ 1593 } 1594 1595 if ( glyphpath->elemIsQueued ) 1596 { 1597 FT_ASSERT( cf2_hintmap_isValid( &glyphpath->hintMap ) ); 1598 1599 cf2_glyphpath_pushPrevElem( glyphpath, 1600 &glyphpath->hintMap, 1601 &P0, 1602 P1, 1603 FALSE ); 1604 } 1605 1606 /* queue the current element with offset points */ 1607 glyphpath->elemIsQueued = TRUE; 1608 glyphpath->prevElemOp = CF2_PathOpLineTo; 1609 glyphpath->prevElemP0 = P0; 1610 glyphpath->prevElemP1 = P1; 1611 1612 /* update current map */ 1613 if ( cf2_hintmask_isNew( glyphpath->hintMask ) ) 1614 cf2_hintmap_build( &glyphpath->hintMap, 1615 glyphpath->hStemHintArray, 1616 glyphpath->vStemHintArray, 1617 glyphpath->hintMask, 1618 glyphpath->hintOriginY, 1619 FALSE ); 1620 1621 glyphpath->currentCS.x = x; /* pre-offset current point */ 1622 glyphpath->currentCS.y = y; 1623 } 1624 1625 1626 FT_LOCAL_DEF( void ) 1627 cf2_glyphpath_curveTo( CF2_GlyphPath glyphpath, 1628 CF2_Fixed x1, 1629 CF2_Fixed y1, 1630 CF2_Fixed x2, 1631 CF2_Fixed y2, 1632 CF2_Fixed x3, 1633 CF2_Fixed y3 ) 1634 { 1635 CF2_Fixed xOffset1, yOffset1, xOffset3, yOffset3; 1636 FT_Vector P0, P1, P2, P3; 1637 1638 1639 /* TODO: ignore zero length portions of curve?? */ 1640 cf2_glyphpath_computeOffset( glyphpath, 1641 glyphpath->currentCS.x, 1642 glyphpath->currentCS.y, 1643 x1, 1644 y1, 1645 &xOffset1, 1646 &yOffset1 ); 1647 cf2_glyphpath_computeOffset( glyphpath, 1648 x2, 1649 y2, 1650 x3, 1651 y3, 1652 &xOffset3, 1653 &yOffset3 ); 1654 1655 /* add momentum from the middle segment */ 1656 glyphpath->callbacks->windingMomentum += 1657 cf2_getWindingMomentum( x1, y1, x2, y2 ); 1658 1659 /* construct offset points */ 1660 P0.x = glyphpath->currentCS.x + xOffset1; 1661 P0.y = glyphpath->currentCS.y + yOffset1; 1662 P1.x = x1 + xOffset1; 1663 P1.y = y1 + yOffset1; 1664 /* note: preserve angle of final segment by using offset3 at both ends */ 1665 P2.x = x2 + xOffset3; 1666 P2.y = y2 + yOffset3; 1667 P3.x = x3 + xOffset3; 1668 P3.y = y3 + yOffset3; 1669 1670 if ( glyphpath->moveIsPending ) 1671 { 1672 /* emit offset 1st point as MoveTo */ 1673 cf2_glyphpath_pushMove( glyphpath, P0 ); 1674 1675 glyphpath->moveIsPending = FALSE; 1676 glyphpath->pathIsOpen = TRUE; 1677 1678 glyphpath->offsetStart1 = P1; /* record second point */ 1679 } 1680 1681 if ( glyphpath->elemIsQueued ) 1682 { 1683 FT_ASSERT( cf2_hintmap_isValid( &glyphpath->hintMap ) ); 1684 1685 cf2_glyphpath_pushPrevElem( glyphpath, 1686 &glyphpath->hintMap, 1687 &P0, 1688 P1, 1689 FALSE ); 1690 } 1691 1692 /* queue the current element with offset points */ 1693 glyphpath->elemIsQueued = TRUE; 1694 glyphpath->prevElemOp = CF2_PathOpCubeTo; 1695 glyphpath->prevElemP0 = P0; 1696 glyphpath->prevElemP1 = P1; 1697 glyphpath->prevElemP2 = P2; 1698 glyphpath->prevElemP3 = P3; 1699 1700 /* update current map */ 1701 if ( cf2_hintmask_isNew( glyphpath->hintMask ) ) 1702 cf2_hintmap_build( &glyphpath->hintMap, 1703 glyphpath->hStemHintArray, 1704 glyphpath->vStemHintArray, 1705 glyphpath->hintMask, 1706 glyphpath->hintOriginY, 1707 FALSE ); 1708 1709 glyphpath->currentCS.x = x3; /* pre-offset current point */ 1710 glyphpath->currentCS.y = y3; 1711 } 1712 1713 1714 FT_LOCAL_DEF( void ) 1715 cf2_glyphpath_closeOpenPath( CF2_GlyphPath glyphpath ) 1716 { 1717 if ( glyphpath->pathIsOpen ) 1718 { 1719 FT_ASSERT( cf2_hintmap_isValid( &glyphpath->firstHintMap ) ); 1720 1721 /* since we need to apply an offset to the implicit lineto, we make */ 1722 /* it explicit here */ 1723 cf2_glyphpath_lineTo( glyphpath, 1724 glyphpath->start.x, 1725 glyphpath->start.y ); 1726 1727 /* Draw previous element (the explicit LineTo we just created, */ 1728 /* above) and connect it to the start point, but with the offset we */ 1729 /* saved from the first element. */ 1730 /* Use the saved HintMap, too. */ 1731 FT_ASSERT( glyphpath->elemIsQueued ); 1732 1733 cf2_glyphpath_pushPrevElem( glyphpath, 1734 &glyphpath->firstHintMap, 1735 &glyphpath->offsetStart0, 1736 glyphpath->offsetStart1, 1737 TRUE ); 1738 1739 /* reset state machine */ 1740 glyphpath->moveIsPending = TRUE; 1741 glyphpath->pathIsOpen = FALSE; 1742 glyphpath->elemIsQueued = FALSE; 1743 } 1744 } 1745 1746 1747/* END */ 1748