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 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, this 605 * is while building the initial map, where captured hints from all 606 * zones are combined. Define overlap to include hints that `touch' 607 * (overlap zero). Hiragino Sans/Gothic fonts have numerous hints that 608 * touch. Some fonts have non-ideographic glyphs that overlap our 609 * synthetic hints. 610 * 611 * Overlap also occurs when darkening stem hints that are close. 612 * 613 */ 614 if ( indexInsert < hintmap->count ) 615 { 616 /* we are inserting before an existing edge: */ 617 /* verify that an existing edge is not the same */ 618 if ( hintmap->edge[indexInsert].csCoord == firstHintEdge->csCoord ) 619 return; /* ignore overlapping stem hint */ 620 621 /* verify that a new pair does not straddle the next edge */ 622 if ( isPair && 623 hintmap->edge[indexInsert].csCoord <= secondHintEdge->csCoord ) 624 return; /* ignore overlapping stem hint */ 625 626 /* verify that we are not inserting between paired edges */ 627 if ( cf2_hint_isPairTop( &hintmap->edge[indexInsert] ) ) 628 return; /* ignore overlapping stem hint */ 629 } 630 631 /* recompute device space locations using initial hint map */ 632 if ( cf2_hintmap_isValid( hintmap->initialHintMap ) && 633 !cf2_hint_isLocked( firstHintEdge ) ) 634 { 635 if ( isPair ) 636 { 637 /* Use hint map to position the center of stem, and nominal scale */ 638 /* to position the two edges. This preserves the stem width. */ 639 CF2_Fixed midpoint = cf2_hintmap_map( 640 hintmap->initialHintMap, 641 ( secondHintEdge->csCoord + 642 firstHintEdge->csCoord ) / 2 ); 643 CF2_Fixed halfWidth = FT_MulFix( 644 ( secondHintEdge->csCoord - 645 firstHintEdge->csCoord ) / 2, 646 hintmap->scale ); 647 648 649 firstHintEdge->dsCoord = midpoint - halfWidth; 650 secondHintEdge->dsCoord = midpoint + halfWidth; 651 } 652 else 653 firstHintEdge->dsCoord = cf2_hintmap_map( hintmap->initialHintMap, 654 firstHintEdge->csCoord ); 655 } 656 657 /* 658 * Discard any hints that overlap in device space; this can occur 659 * because locked hints have been moved to align with blue zones. 660 * 661 * TODO: Although we might correct this later during adjustment, we 662 * don't currently have a way to delete a conflicting hint once it has 663 * been inserted. See v2.030 MinionPro-Regular, 12 ppem darkened, 664 * initial hint map for second path, glyph 945 (the perispomeni (tilde) 665 * in U+1F6E, Greek omega with psili and perispomeni). Darkening is 666 * 25. Pair 667,747 initially conflicts in design space with top edge 667 * 660. This is because 667 maps to 7.87, and the top edge was 668 * captured by a zone at 8.0. The pair is later successfully inserted 669 * in a zone without the top edge. In this zone it is adjusted to 8.0, 670 * and no longer conflicts with the top edge in design space. This 671 * means it can be included in yet a later zone which does have the top 672 * edge hint. This produces a small mismatch between the first and 673 * last points of this path, even though the hint masks are the same. 674 * The density map difference is tiny (1/256). 675 * 676 */ 677 678 if ( indexInsert > 0 ) 679 { 680 /* we are inserting after an existing edge */ 681 if ( firstHintEdge->dsCoord < hintmap->edge[indexInsert - 1].dsCoord ) 682 return; 683 } 684 685 if ( indexInsert < hintmap->count ) 686 { 687 /* we are inserting before an existing edge */ 688 if ( isPair ) 689 { 690 if ( secondHintEdge->dsCoord > hintmap->edge[indexInsert].dsCoord ) 691 return; 692 } 693 else 694 { 695 if ( firstHintEdge->dsCoord > hintmap->edge[indexInsert].dsCoord ) 696 return; 697 } 698 } 699 700 /* make room to insert */ 701 { 702 CF2_Int iSrc = hintmap->count - 1; 703 CF2_Int iDst = isPair ? hintmap->count + 1 : hintmap->count; 704 705 CF2_Int count = hintmap->count - indexInsert; 706 707 708 if ( iDst >= CF2_MAX_HINT_EDGES ) 709 { 710 FT_TRACE4(( "cf2_hintmap_insertHint: too many hintmaps\n" )); 711 return; 712 } 713 714 while ( count-- ) 715 hintmap->edge[iDst--] = hintmap->edge[iSrc--]; 716 717 /* insert first edge */ 718 hintmap->edge[indexInsert] = *firstHintEdge; /* copy struct */ 719 hintmap->count += 1; 720 721 if ( isPair ) 722 { 723 /* insert second edge */ 724 hintmap->edge[indexInsert + 1] = *secondHintEdge; /* copy struct */ 725 hintmap->count += 1; 726 } 727 } 728 729 return; 730 } 731 732 733 /* 734 * Build a map from hints and mask. 735 * 736 * This function may recur one level if `hintmap->initialHintMap' is not yet 737 * valid. 738 * If `initialMap' is true, simply build initial map. 739 * 740 * Synthetic hints are used in two ways. A hint at zero is inserted, if 741 * needed, in the initial hint map, to prevent translations from 742 * propagating across the origin. If synthetic em box hints are enabled 743 * for ideographic dictionaries, then they are inserted in all hint 744 * maps, including the initial one. 745 * 746 */ 747 FT_LOCAL_DEF( void ) 748 cf2_hintmap_build( CF2_HintMap hintmap, 749 CF2_ArrStack hStemHintArray, 750 CF2_ArrStack vStemHintArray, 751 CF2_HintMask hintMask, 752 CF2_Fixed hintOrigin, 753 FT_Bool initialMap ) 754 { 755 FT_Byte* maskPtr; 756 757 CF2_Font font = hintmap->font; 758 CF2_HintMaskRec tempHintMask; 759 760 size_t bitCount, i; 761 FT_Byte maskByte; 762 763 764 /* check whether initial map is constructed */ 765 if ( !initialMap && !cf2_hintmap_isValid( hintmap->initialHintMap ) ) 766 { 767 /* make recursive call with initialHintMap and temporary mask; */ 768 /* temporary mask will get all bits set, below */ 769 cf2_hintmask_init( &tempHintMask, hintMask->error ); 770 cf2_hintmap_build( hintmap->initialHintMap, 771 hStemHintArray, 772 vStemHintArray, 773 &tempHintMask, 774 hintOrigin, 775 TRUE ); 776 } 777 778 if ( !cf2_hintmask_isValid( hintMask ) ) 779 { 780 /* without a hint mask, assume all hints are active */ 781 cf2_hintmask_setAll( hintMask, 782 cf2_arrstack_size( hStemHintArray ) + 783 cf2_arrstack_size( vStemHintArray ) ); 784 if ( !cf2_hintmask_isValid( hintMask ) ) 785 return; /* too many stem hints */ 786 } 787 788 /* begin by clearing the map */ 789 hintmap->count = 0; 790 hintmap->lastIndex = 0; 791 792 /* make a copy of the hint mask so we can modify it */ 793 tempHintMask = *hintMask; 794 maskPtr = cf2_hintmask_getMaskPtr( &tempHintMask ); 795 796 /* use the hStem hints only, which are first in the mask */ 797 /* TODO: compare this to cffhintmaskGetBitCount */ 798 bitCount = cf2_arrstack_size( hStemHintArray ); 799 800 /* synthetic embox hints get highest priority */ 801 if ( font->blues.doEmBoxHints ) 802 { 803 CF2_HintRec dummy; 804 805 806 cf2_hint_initZero( &dummy ); /* invalid hint map element */ 807 808 /* ghost bottom */ 809 cf2_hintmap_insertHint( hintmap, 810 &font->blues.emBoxBottomEdge, 811 &dummy ); 812 /* ghost top */ 813 cf2_hintmap_insertHint( hintmap, 814 &dummy, 815 &font->blues.emBoxTopEdge ); 816 } 817 818 /* insert hints captured by a blue zone or already locked (higher */ 819 /* priority) */ 820 for ( i = 0, maskByte = 0x80; i < bitCount; i++ ) 821 { 822 if ( maskByte & *maskPtr ) 823 { 824 /* expand StemHint into two `CF2_Hint' elements */ 825 CF2_HintRec bottomHintEdge, topHintEdge; 826 827 828 cf2_hint_init( &bottomHintEdge, 829 hStemHintArray, 830 i, 831 font, 832 hintOrigin, 833 hintmap->scale, 834 TRUE /* bottom */ ); 835 cf2_hint_init( &topHintEdge, 836 hStemHintArray, 837 i, 838 font, 839 hintOrigin, 840 hintmap->scale, 841 FALSE /* top */ ); 842 843 if ( cf2_hint_isLocked( &bottomHintEdge ) || 844 cf2_hint_isLocked( &topHintEdge ) || 845 cf2_blues_capture( &font->blues, 846 &bottomHintEdge, 847 &topHintEdge ) ) 848 { 849 /* insert captured hint into map */ 850 cf2_hintmap_insertHint( hintmap, &bottomHintEdge, &topHintEdge ); 851 852 *maskPtr &= ~maskByte; /* turn off the bit for this hint */ 853 } 854 } 855 856 if ( ( i & 7 ) == 7 ) 857 { 858 /* move to next mask byte */ 859 maskPtr++; 860 maskByte = 0x80; 861 } 862 else 863 maskByte >>= 1; 864 } 865 866 /* initial hint map includes only captured hints plus maybe one at 0 */ 867 868 /* 869 * TODO: There is a problem here because we are trying to build a 870 * single hint map containing all captured hints. It is 871 * possible for there to be conflicts between captured hints, 872 * either because of darkening or because the hints are in 873 * separate hint zones (we are ignoring hint zones for the 874 * initial map). An example of the latter is MinionPro-Regular 875 * v2.030 glyph 883 (Greek Capital Alpha with Psili) at 15ppem. 876 * A stem hint for the psili conflicts with the top edge hint 877 * for the base character. The stem hint gets priority because 878 * of its sort order. In glyph 884 (Greek Capital Alpha with 879 * Psili and Oxia), the top of the base character gets a stem 880 * hint, and the psili does not. This creates different initial 881 * maps for the two glyphs resulting in different renderings of 882 * the base character. Will probably defer this either as not 883 * worth the cost or as a font bug. I don't think there is any 884 * good reason for an accent to be captured by an alignment 885 * zone. -darnold 2/12/10 886 */ 887 888 if ( initialMap ) 889 { 890 /* Apply a heuristic that inserts a point for (0,0), unless it's */ 891 /* already covered by a mapping. This locks the baseline for glyphs */ 892 /* that have no baseline hints. */ 893 894 if ( hintmap->count == 0 || 895 hintmap->edge[0].csCoord > 0 || 896 hintmap->edge[hintmap->count - 1].csCoord < 0 ) 897 { 898 /* all edges are above 0 or all edges are below 0; */ 899 /* construct a locked edge hint at 0 */ 900 901 CF2_HintRec edge, invalid; 902 903 904 cf2_hint_initZero( &edge ); 905 906 edge.flags = CF2_GhostBottom | 907 CF2_Locked | 908 CF2_Synthetic; 909 edge.scale = hintmap->scale; 910 911 cf2_hint_initZero( &invalid ); 912 cf2_hintmap_insertHint( hintmap, &edge, &invalid ); 913 } 914 } 915 else 916 { 917 /* insert remaining hints */ 918 919 maskPtr = cf2_hintmask_getMaskPtr( &tempHintMask ); 920 921 for ( i = 0, maskByte = 0x80; i < bitCount; i++ ) 922 { 923 if ( maskByte & *maskPtr ) 924 { 925 CF2_HintRec bottomHintEdge, topHintEdge; 926 927 928 cf2_hint_init( &bottomHintEdge, 929 hStemHintArray, 930 i, 931 font, 932 hintOrigin, 933 hintmap->scale, 934 TRUE /* bottom */ ); 935 cf2_hint_init( &topHintEdge, 936 hStemHintArray, 937 i, 938 font, 939 hintOrigin, 940 hintmap->scale, 941 FALSE /* top */ ); 942 943 cf2_hintmap_insertHint( hintmap, &bottomHintEdge, &topHintEdge ); 944 } 945 946 if ( ( i & 7 ) == 7 ) 947 { 948 /* move to next mask byte */ 949 maskPtr++; 950 maskByte = 0x80; 951 } 952 else 953 maskByte >>= 1; 954 } 955 } 956 957 /* 958 * Note: The following line is a convenient place to break when 959 * debugging hinting. Examine `hintmap->edge' for the list of 960 * enabled hints, then step over the call to see the effect of 961 * adjustment. We stop here first on the recursive call that 962 * creates the initial map, and then on each counter group and 963 * hint zone. 964 */ 965 966 /* adjust positions of hint edges that are not locked to blue zones */ 967 cf2_hintmap_adjustHints( hintmap ); 968 969 /* save the position of all hints that were used in this hint map; */ 970 /* if we use them again, we'll locate them in the same position */ 971 if ( !initialMap ) 972 { 973 for ( i = 0; i < hintmap->count; i++ ) 974 { 975 if ( !cf2_hint_isSynthetic( &hintmap->edge[i] ) ) 976 { 977 /* Note: include both valid and invalid edges */ 978 /* Note: top and bottom edges are copied back separately */ 979 CF2_StemHint stemhint = (CF2_StemHint) 980 cf2_arrstack_getPointer( hStemHintArray, 981 hintmap->edge[i].index ); 982 983 984 if ( cf2_hint_isTop( &hintmap->edge[i] ) ) 985 stemhint->maxDS = hintmap->edge[i].dsCoord; 986 else 987 stemhint->minDS = hintmap->edge[i].dsCoord; 988 989 stemhint->used = TRUE; 990 } 991 } 992 } 993 994 /* hint map is ready to use */ 995 hintmap->isValid = TRUE; 996 997 /* remember this mask has been used */ 998 cf2_hintmask_setNew( hintMask, FALSE ); 999 } 1000 1001 1002 FT_LOCAL_DEF( void ) 1003 cf2_glyphpath_init( CF2_GlyphPath glyphpath, 1004 CF2_Font font, 1005 CF2_OutlineCallbacks callbacks, 1006 CF2_Fixed scaleY, 1007 /* CF2_Fixed hShift, */ 1008 CF2_ArrStack hStemHintArray, 1009 CF2_ArrStack vStemHintArray, 1010 CF2_HintMask hintMask, 1011 CF2_Fixed hintOriginY, 1012 const CF2_Blues blues, 1013 const FT_Vector* fractionalTranslation ) 1014 { 1015 FT_ZERO( glyphpath ); 1016 1017 glyphpath->font = font; 1018 glyphpath->callbacks = callbacks; 1019 1020 cf2_arrstack_init( &glyphpath->hintMoves, 1021 font->memory, 1022 &font->error, 1023 sizeof ( CF2_HintMoveRec ) ); 1024 1025 cf2_hintmap_init( &glyphpath->initialHintMap, 1026 font, 1027 &glyphpath->initialHintMap, 1028 &glyphpath->hintMoves, 1029 scaleY ); 1030 cf2_hintmap_init( &glyphpath->firstHintMap, 1031 font, 1032 &glyphpath->initialHintMap, 1033 &glyphpath->hintMoves, 1034 scaleY ); 1035 cf2_hintmap_init( &glyphpath->hintMap, 1036 font, 1037 &glyphpath->initialHintMap, 1038 &glyphpath->hintMoves, 1039 scaleY ); 1040 1041 glyphpath->scaleX = font->innerTransform.a; 1042 glyphpath->scaleC = font->innerTransform.c; 1043 glyphpath->scaleY = font->innerTransform.d; 1044 1045 glyphpath->fractionalTranslation = *fractionalTranslation; 1046 1047 #if 0 1048 glyphpath->hShift = hShift; /* for fauxing */ 1049 #endif 1050 1051 glyphpath->hStemHintArray = hStemHintArray; 1052 glyphpath->vStemHintArray = vStemHintArray; 1053 glyphpath->hintMask = hintMask; /* ptr to current mask */ 1054 glyphpath->hintOriginY = hintOriginY; 1055 glyphpath->blues = blues; 1056 glyphpath->darken = font->darkened; /* TODO: should we make copies? */ 1057 glyphpath->xOffset = font->darkenX; 1058 glyphpath->yOffset = font->darkenY; 1059 glyphpath->miterLimit = 2 * FT_MAX( 1060 cf2_fixedAbs( glyphpath->xOffset ), 1061 cf2_fixedAbs( glyphpath->yOffset ) ); 1062 1063 /* .1 character space unit */ 1064 glyphpath->snapThreshold = cf2_floatToFixed( 0.1f ); 1065 1066 glyphpath->moveIsPending = TRUE; 1067 glyphpath->pathIsOpen = FALSE; 1068 glyphpath->pathIsClosing = FALSE; 1069 glyphpath->elemIsQueued = FALSE; 1070 } 1071 1072 1073 FT_LOCAL_DEF( void ) 1074 cf2_glyphpath_finalize( CF2_GlyphPath glyphpath ) 1075 { 1076 cf2_arrstack_finalize( &glyphpath->hintMoves ); 1077 } 1078 1079 1080 /* 1081 * Hint point in y-direction and apply outerTransform. 1082 * Input `current' hint map (which is actually delayed by one element). 1083 * Input x,y point in Character Space. 1084 * Output x,y point in Device Space, including translation. 1085 */ 1086 static void 1087 cf2_glyphpath_hintPoint( CF2_GlyphPath glyphpath, 1088 CF2_HintMap hintmap, 1089 FT_Vector* ppt, 1090 CF2_Fixed x, 1091 CF2_Fixed y ) 1092 { 1093 FT_Vector pt; /* hinted point in upright DS */ 1094 1095 1096 pt.x = FT_MulFix( glyphpath->scaleX, x ) + 1097 FT_MulFix( glyphpath->scaleC, y ); 1098 pt.y = cf2_hintmap_map( hintmap, y ); 1099 1100 ppt->x = FT_MulFix( glyphpath->font->outerTransform.a, pt.x ) + 1101 FT_MulFix( glyphpath->font->outerTransform.c, pt.y ) + 1102 glyphpath->fractionalTranslation.x; 1103 ppt->y = FT_MulFix( glyphpath->font->outerTransform.b, pt.x ) + 1104 FT_MulFix( glyphpath->font->outerTransform.d, pt.y ) + 1105 glyphpath->fractionalTranslation.y; 1106 } 1107 1108 1109 /* 1110 * From two line segments, (u1,u2) and (v1,v2), compute a point of 1111 * intersection on the corresponding lines. 1112 * Return false if no intersection is found, or if the intersection is 1113 * too far away from the ends of the line segments, u2 and v1. 1114 * 1115 */ 1116 static FT_Bool 1117 cf2_glyphpath_computeIntersection( CF2_GlyphPath glyphpath, 1118 const FT_Vector* u1, 1119 const FT_Vector* u2, 1120 const FT_Vector* v1, 1121 const FT_Vector* v2, 1122 FT_Vector* intersection ) 1123 { 1124 /* 1125 * Let `u' be a zero-based vector from the first segment, `v' from the 1126 * second segment. 1127 * Let `w 'be the zero-based vector from `u1' to `v1'. 1128 * `perp' is the `perpendicular dot product'; see 1129 * http://mathworld.wolfram.com/PerpDotProduct.html. 1130 * `s' is the parameter for the parametric line for the first segment 1131 * (`u'). 1132 * 1133 * See notation in 1134 * http://softsurfer.com/Archive/algorithm_0104/algorithm_0104B.htm. 1135 * Calculations are done in 16.16, but must handle the squaring of 1136 * line lengths in character space. We scale all vectors by 1/32 to 1137 * avoid overflow. This allows values up to 4095 to be squared. The 1138 * scale factor cancels in the divide. 1139 * 1140 * TODO: the scale factor could be computed from UnitsPerEm. 1141 * 1142 */ 1143 1144 #define cf2_perp( a, b ) \ 1145 ( FT_MulFix( a.x, b.y ) - FT_MulFix( a.y, b.x ) ) 1146 1147 /* round and divide by 32 */ 1148 #define CF2_CS_SCALE( x ) \ 1149 ( ( (x) + 0x10 ) >> 5 ) 1150 1151 FT_Vector u, v, w; /* scaled vectors */ 1152 CF2_Fixed denominator, s; 1153 1154 1155 u.x = CF2_CS_SCALE( u2->x - u1->x ); 1156 u.y = CF2_CS_SCALE( u2->y - u1->y ); 1157 v.x = CF2_CS_SCALE( v2->x - v1->x ); 1158 v.y = CF2_CS_SCALE( v2->y - v1->y ); 1159 w.x = CF2_CS_SCALE( v1->x - u1->x ); 1160 w.y = CF2_CS_SCALE( v1->y - u1->y ); 1161 1162 denominator = cf2_perp( u, v ); 1163 1164 if ( denominator == 0 ) 1165 return FALSE; /* parallel or coincident lines */ 1166 1167 s = FT_DivFix( cf2_perp( w, v ), denominator ); 1168 1169 intersection->x = u1->x + FT_MulFix( s, u2->x - u1->x ); 1170 intersection->y = u1->y + FT_MulFix( s, u2->y - u1->y ); 1171 1172 /* 1173 * Special case snapping for horizontal and vertical lines. 1174 * This cleans up intersections and reduces problems with winding 1175 * order detection. 1176 * Sample case is sbc cd KozGoPr6N-Medium.otf 20 16685. 1177 * Note: these calculations are in character space. 1178 * 1179 */ 1180 1181 if ( u1->x == u2->x && 1182 cf2_fixedAbs( intersection->x - u1->x ) < glyphpath->snapThreshold ) 1183 intersection->x = u1->x; 1184 if ( u1->y == u2->y && 1185 cf2_fixedAbs( intersection->y - u1->y ) < glyphpath->snapThreshold ) 1186 intersection->y = u1->y; 1187 1188 if ( v1->x == v2->x && 1189 cf2_fixedAbs( intersection->x - v1->x ) < glyphpath->snapThreshold ) 1190 intersection->x = v1->x; 1191 if ( v1->y == v2->y && 1192 cf2_fixedAbs( intersection->y - v1->y ) < glyphpath->snapThreshold ) 1193 intersection->y = v1->y; 1194 1195 /* limit the intersection distance from midpoint of u2 and v1 */ 1196 if ( cf2_fixedAbs( intersection->x - ( u2->x + v1->x ) / 2 ) > 1197 glyphpath->miterLimit || 1198 cf2_fixedAbs( intersection->y - ( u2->y + v1->y ) / 2 ) > 1199 glyphpath->miterLimit ) 1200 return FALSE; 1201 1202 return TRUE; 1203 } 1204 1205 1206 /* 1207 * Push the cached element (glyphpath->prevElem*) to the outline 1208 * consumer. When a darkening offset is used, the end point of the 1209 * cached element may be adjusted to an intersection point or we may 1210 * synthesize a connecting line to the current element. If we are 1211 * closing a subpath, we may also generate a connecting line to the start 1212 * point. 1213 * 1214 * This is where Character Space (CS) is converted to Device Space (DS) 1215 * using a hint map. This calculation must use a HintMap that was valid 1216 * at the time the element was saved. For the first point in a subpath, 1217 * that is a saved HintMap. For most elements, it just means the caller 1218 * has delayed building a HintMap from the current HintMask. 1219 * 1220 * Transform each point with outerTransform and call the outline 1221 * callbacks. This is a general 3x3 transform: 1222 * 1223 * x' = a*x + c*y + tx, y' = b*x + d*y + ty 1224 * 1225 * but it uses 4 elements from CF2_Font and the translation part 1226 * from CF2_GlyphPath. 1227 * 1228 */ 1229 static void 1230 cf2_glyphpath_pushPrevElem( CF2_GlyphPath glyphpath, 1231 CF2_HintMap hintmap, 1232 FT_Vector* nextP0, 1233 FT_Vector nextP1, 1234 FT_Bool close ) 1235 { 1236 CF2_CallbackParamsRec params; 1237 1238 FT_Vector* prevP0; 1239 FT_Vector* prevP1; 1240 1241 FT_Vector intersection = { 0, 0 }; 1242 FT_Bool useIntersection = FALSE; 1243 1244 1245 FT_ASSERT( glyphpath->prevElemOp == CF2_PathOpLineTo || 1246 glyphpath->prevElemOp == CF2_PathOpCubeTo ); 1247 1248 if ( glyphpath->prevElemOp == CF2_PathOpLineTo ) 1249 { 1250 prevP0 = &glyphpath->prevElemP0; 1251 prevP1 = &glyphpath->prevElemP1; 1252 } 1253 else 1254 { 1255 prevP0 = &glyphpath->prevElemP2; 1256 prevP1 = &glyphpath->prevElemP3; 1257 } 1258 1259 /* optimization: if previous and next elements are offset by the same */ 1260 /* amount, then there will be no gap, and no need to compute an */ 1261 /* intersection. */ 1262 if ( prevP1->x != nextP0->x || prevP1->y != nextP0->y ) 1263 { 1264 /* previous element does not join next element: */ 1265 /* adjust end point of previous element to the intersection */ 1266 useIntersection = cf2_glyphpath_computeIntersection( glyphpath, 1267 prevP0, 1268 prevP1, 1269 nextP0, 1270 &nextP1, 1271 &intersection ); 1272 if ( useIntersection ) 1273 { 1274 /* modify the last point of the cached element (either line or */ 1275 /* curve) */ 1276 *prevP1 = intersection; 1277 } 1278 } 1279 1280 params.pt0 = glyphpath->currentDS; 1281 1282 switch( glyphpath->prevElemOp ) 1283 { 1284 case CF2_PathOpLineTo: 1285 params.op = CF2_PathOpLineTo; 1286 1287 /* note: pt2 and pt3 are unused */ 1288 1289 if ( close ) 1290 { 1291 /* use first hint map if closing */ 1292 cf2_glyphpath_hintPoint( glyphpath, 1293 &glyphpath->firstHintMap, 1294 ¶ms.pt1, 1295 glyphpath->prevElemP1.x, 1296 glyphpath->prevElemP1.y ); 1297 } 1298 else 1299 { 1300 cf2_glyphpath_hintPoint( glyphpath, 1301 hintmap, 1302 ¶ms.pt1, 1303 glyphpath->prevElemP1.x, 1304 glyphpath->prevElemP1.y ); 1305 } 1306 1307 /* output only non-zero length lines */ 1308 if ( params.pt0.x != params.pt1.x || params.pt0.y != params.pt1.y ) 1309 { 1310 glyphpath->callbacks->lineTo( glyphpath->callbacks, ¶ms ); 1311 1312 glyphpath->currentDS = params.pt1; 1313 } 1314 break; 1315 1316 case CF2_PathOpCubeTo: 1317 params.op = CF2_PathOpCubeTo; 1318 1319 /* TODO: should we intersect the interior joins (p1-p2 and p2-p3)? */ 1320 cf2_glyphpath_hintPoint( glyphpath, 1321 hintmap, 1322 ¶ms.pt1, 1323 glyphpath->prevElemP1.x, 1324 glyphpath->prevElemP1.y ); 1325 cf2_glyphpath_hintPoint( glyphpath, 1326 hintmap, 1327 ¶ms.pt2, 1328 glyphpath->prevElemP2.x, 1329 glyphpath->prevElemP2.y ); 1330 cf2_glyphpath_hintPoint( glyphpath, 1331 hintmap, 1332 ¶ms.pt3, 1333 glyphpath->prevElemP3.x, 1334 glyphpath->prevElemP3.y ); 1335 1336 glyphpath->callbacks->cubeTo( glyphpath->callbacks, ¶ms ); 1337 1338 glyphpath->currentDS = params.pt3; 1339 1340 break; 1341 } 1342 1343 if ( !useIntersection || close ) 1344 { 1345 /* insert connecting line between end of previous element and start */ 1346 /* of current one */ 1347 /* note: at the end of a subpath, we might do both, so use `nextP0' */ 1348 /* before we change it, below */ 1349 1350 if ( close ) 1351 { 1352 /* if we are closing the subpath, then nextP0 is in the first */ 1353 /* hint zone */ 1354 cf2_glyphpath_hintPoint( glyphpath, 1355 &glyphpath->firstHintMap, 1356 ¶ms.pt1, 1357 nextP0->x, 1358 nextP0->y ); 1359 } 1360 else 1361 { 1362 cf2_glyphpath_hintPoint( glyphpath, 1363 hintmap, 1364 ¶ms.pt1, 1365 nextP0->x, 1366 nextP0->y ); 1367 } 1368 1369 if ( params.pt1.x != glyphpath->currentDS.x || 1370 params.pt1.y != glyphpath->currentDS.y ) 1371 { 1372 /* length is nonzero */ 1373 params.op = CF2_PathOpLineTo; 1374 params.pt0 = glyphpath->currentDS; 1375 1376 /* note: pt2 and pt3 are unused */ 1377 glyphpath->callbacks->lineTo( glyphpath->callbacks, ¶ms ); 1378 1379 glyphpath->currentDS = params.pt1; 1380 } 1381 } 1382 1383 if ( useIntersection ) 1384 { 1385 /* return intersection point to caller */ 1386 *nextP0 = intersection; 1387 } 1388 } 1389 1390 1391 /* push a MoveTo element based on current point and offset of current */ 1392 /* element */ 1393 static void 1394 cf2_glyphpath_pushMove( CF2_GlyphPath glyphpath, 1395 FT_Vector start ) 1396 { 1397 CF2_CallbackParamsRec params; 1398 1399 1400 params.op = CF2_PathOpMoveTo; 1401 params.pt0 = glyphpath->currentDS; 1402 1403 /* Test if move has really happened yet; it would have called */ 1404 /* `cf2_hintmap_build' to set `isValid'. */ 1405 if ( !cf2_hintmap_isValid( &glyphpath->hintMap ) ) 1406 { 1407 /* we are here iff first subpath is missing a moveto operator: */ 1408 /* synthesize first moveTo to finish initialization of hintMap */ 1409 cf2_glyphpath_moveTo( glyphpath, 1410 glyphpath->start.x, 1411 glyphpath->start.y ); 1412 } 1413 1414 cf2_glyphpath_hintPoint( glyphpath, 1415 &glyphpath->hintMap, 1416 ¶ms.pt1, 1417 start.x, 1418 start.y ); 1419 1420 /* note: pt2 and pt3 are unused */ 1421 glyphpath->callbacks->moveTo( glyphpath->callbacks, ¶ms ); 1422 1423 glyphpath->currentDS = params.pt1; 1424 glyphpath->offsetStart0 = start; 1425 } 1426 1427 1428 /* 1429 * All coordinates are in character space. 1430 * On input, (x1, y1) and (x2, y2) give line segment. 1431 * On output, (x, y) give offset vector. 1432 * We use a piecewise approximation to trig functions. 1433 * 1434 * TODO: Offset true perpendicular and proper length 1435 * supply the y-translation for hinting here, too, 1436 * that adds yOffset unconditionally to *y. 1437 */ 1438 static void 1439 cf2_glyphpath_computeOffset( CF2_GlyphPath glyphpath, 1440 CF2_Fixed x1, 1441 CF2_Fixed y1, 1442 CF2_Fixed x2, 1443 CF2_Fixed y2, 1444 CF2_Fixed* x, 1445 CF2_Fixed* y ) 1446 { 1447 CF2_Fixed dx = x2 - x1; 1448 CF2_Fixed dy = y2 - y1; 1449 1450 1451 /* note: negative offsets don't work here; negate deltas to change */ 1452 /* quadrants, below */ 1453 if ( glyphpath->font->reverseWinding ) 1454 { 1455 dx = -dx; 1456 dy = -dy; 1457 } 1458 1459 *x = *y = 0; 1460 1461 if ( !glyphpath->darken ) 1462 return; 1463 1464 /* add momentum for this path element */ 1465 glyphpath->callbacks->windingMomentum += 1466 cf2_getWindingMomentum( x1, y1, x2, y2 ); 1467 1468 /* note: allow mixed integer and fixed multiplication here */ 1469 if ( dx >= 0 ) 1470 { 1471 if ( dy >= 0 ) 1472 { 1473 /* first quadrant, +x +y */ 1474 1475 if ( dx > 2 * dy ) 1476 { 1477 /* +x */ 1478 *x = 0; 1479 *y = 0; 1480 } 1481 else if ( dy > 2 * dx ) 1482 { 1483 /* +y */ 1484 *x = glyphpath->xOffset; 1485 *y = glyphpath->yOffset; 1486 } 1487 else 1488 { 1489 /* +x +y */ 1490 *x = FT_MulFix( cf2_floatToFixed( 0.7 ), 1491 glyphpath->xOffset ); 1492 *y = FT_MulFix( cf2_floatToFixed( 1.0 - 0.7 ), 1493 glyphpath->yOffset ); 1494 } 1495 } 1496 else 1497 { 1498 /* fourth quadrant, +x -y */ 1499 1500 if ( dx > -2 * dy ) 1501 { 1502 /* +x */ 1503 *x = 0; 1504 *y = 0; 1505 } 1506 else if ( -dy > 2 * dx ) 1507 { 1508 /* -y */ 1509 *x = -glyphpath->xOffset; 1510 *y = glyphpath->yOffset; 1511 } 1512 else 1513 { 1514 /* +x -y */ 1515 *x = FT_MulFix( cf2_floatToFixed( -0.7 ), 1516 glyphpath->xOffset ); 1517 *y = FT_MulFix( cf2_floatToFixed( 1.0 - 0.7 ), 1518 glyphpath->yOffset ); 1519 } 1520 } 1521 } 1522 else 1523 { 1524 if ( dy >= 0 ) 1525 { 1526 /* second quadrant, -x +y */ 1527 1528 if ( -dx > 2 * dy ) 1529 { 1530 /* -x */ 1531 *x = 0; 1532 *y = 2 * glyphpath->yOffset; 1533 } 1534 else if ( dy > -2 * dx ) 1535 { 1536 /* +y */ 1537 *x = glyphpath->xOffset; 1538 *y = glyphpath->yOffset; 1539 } 1540 else 1541 { 1542 /* -x +y */ 1543 *x = FT_MulFix( cf2_floatToFixed( 0.7 ), 1544 glyphpath->xOffset ); 1545 *y = FT_MulFix( cf2_floatToFixed( 1.0 + 0.7 ), 1546 glyphpath->yOffset ); 1547 } 1548 } 1549 else 1550 { 1551 /* third quadrant, -x -y */ 1552 1553 if ( -dx > -2 * dy ) 1554 { 1555 /* -x */ 1556 *x = 0; 1557 *y = 2 * glyphpath->yOffset; 1558 } 1559 else if ( -dy > -2 * dx ) 1560 { 1561 /* -y */ 1562 *x = -glyphpath->xOffset; 1563 *y = glyphpath->yOffset; 1564 } 1565 else 1566 { 1567 /* -x -y */ 1568 *x = FT_MulFix( cf2_floatToFixed( -0.7 ), 1569 glyphpath->xOffset ); 1570 *y = FT_MulFix( cf2_floatToFixed( 1.0 + 0.7 ), 1571 glyphpath->yOffset ); 1572 } 1573 } 1574 } 1575 } 1576 1577 1578 /* 1579 * The functions cf2_glyphpath_{moveTo,lineTo,curveTo,closeOpenPath} are 1580 * called by the interpreter with Character Space (CS) coordinates. Each 1581 * path element is placed into a queue of length one to await the 1582 * calculation of the following element. At that time, the darkening 1583 * offset of the following element is known and joins can be computed, 1584 * including possible modification of this element, before mapping to 1585 * Device Space (DS) and passing it on to the outline consumer. 1586 * 1587 */ 1588 FT_LOCAL_DEF( void ) 1589 cf2_glyphpath_moveTo( CF2_GlyphPath glyphpath, 1590 CF2_Fixed x, 1591 CF2_Fixed y ) 1592 { 1593 cf2_glyphpath_closeOpenPath( glyphpath ); 1594 1595 /* save the parameters of the move for later, when we'll know how to */ 1596 /* offset it; */ 1597 /* also save last move point */ 1598 glyphpath->currentCS.x = glyphpath->start.x = x; 1599 glyphpath->currentCS.y = glyphpath->start.y = y; 1600 1601 glyphpath->moveIsPending = TRUE; 1602 1603 /* ensure we have a valid map with current mask */ 1604 if ( !cf2_hintmap_isValid( &glyphpath->hintMap ) || 1605 cf2_hintmask_isNew( glyphpath->hintMask ) ) 1606 cf2_hintmap_build( &glyphpath->hintMap, 1607 glyphpath->hStemHintArray, 1608 glyphpath->vStemHintArray, 1609 glyphpath->hintMask, 1610 glyphpath->hintOriginY, 1611 FALSE ); 1612 1613 /* save a copy of current HintMap to use when drawing initial point */ 1614 glyphpath->firstHintMap = glyphpath->hintMap; /* structure copy */ 1615 } 1616 1617 1618 FT_LOCAL_DEF( void ) 1619 cf2_glyphpath_lineTo( CF2_GlyphPath glyphpath, 1620 CF2_Fixed x, 1621 CF2_Fixed y ) 1622 { 1623 CF2_Fixed xOffset, yOffset; 1624 FT_Vector P0, P1; 1625 FT_Bool newHintMap; 1626 1627 /* 1628 * New hints will be applied after cf2_glyphpath_pushPrevElem has run. 1629 * In case this is a synthesized closing line, any new hints should be 1630 * delayed until this path is closed (`cf2_hintmask_isNew' will be 1631 * called again before the next line or curve). 1632 */ 1633 1634 /* true if new hint map not on close */ 1635 newHintMap = cf2_hintmask_isNew( glyphpath->hintMask ) && 1636 !glyphpath->pathIsClosing; 1637 1638 /* 1639 * Zero-length lines may occur in the charstring. Because we cannot 1640 * compute darkening offsets or intersections from zero-length lines, 1641 * it is best to remove them and avoid artifacts. However, zero-length 1642 * lines in CS at the start of a new hint map can generate non-zero 1643 * lines in DS due to hint substitution. We detect a change in hint 1644 * map here and pass those zero-length lines along. 1645 */ 1646 1647 /* 1648 * Note: Find explicitly closed paths here with a conditional 1649 * breakpoint using 1650 * 1651 * !gp->pathIsClosing && gp->start.x == x && gp->start.y == y 1652 * 1653 */ 1654 1655 if ( glyphpath->currentCS.x == x && 1656 glyphpath->currentCS.y == y && 1657 !newHintMap ) 1658 /* 1659 * Ignore zero-length lines in CS where the hint map is the same 1660 * because the line in DS will also be zero length. 1661 * 1662 * Ignore zero-length lines when we synthesize a closing line because 1663 * the close will be handled in cf2_glyphPath_pushPrevElem. 1664 */ 1665 return; 1666 1667 cf2_glyphpath_computeOffset( glyphpath, 1668 glyphpath->currentCS.x, 1669 glyphpath->currentCS.y, 1670 x, 1671 y, 1672 &xOffset, 1673 &yOffset ); 1674 1675 /* construct offset points */ 1676 P0.x = glyphpath->currentCS.x + xOffset; 1677 P0.y = glyphpath->currentCS.y + yOffset; 1678 P1.x = x + xOffset; 1679 P1.y = y + yOffset; 1680 1681 if ( glyphpath->moveIsPending ) 1682 { 1683 /* emit offset 1st point as MoveTo */ 1684 cf2_glyphpath_pushMove( glyphpath, P0 ); 1685 1686 glyphpath->moveIsPending = FALSE; /* adjust state machine */ 1687 glyphpath->pathIsOpen = TRUE; 1688 1689 glyphpath->offsetStart1 = P1; /* record second point */ 1690 } 1691 1692 if ( glyphpath->elemIsQueued ) 1693 { 1694 FT_ASSERT( cf2_hintmap_isValid( &glyphpath->hintMap ) ); 1695 1696 cf2_glyphpath_pushPrevElem( glyphpath, 1697 &glyphpath->hintMap, 1698 &P0, 1699 P1, 1700 FALSE ); 1701 } 1702 1703 /* queue the current element with offset points */ 1704 glyphpath->elemIsQueued = TRUE; 1705 glyphpath->prevElemOp = CF2_PathOpLineTo; 1706 glyphpath->prevElemP0 = P0; 1707 glyphpath->prevElemP1 = P1; 1708 1709 /* update current map */ 1710 if ( newHintMap ) 1711 cf2_hintmap_build( &glyphpath->hintMap, 1712 glyphpath->hStemHintArray, 1713 glyphpath->vStemHintArray, 1714 glyphpath->hintMask, 1715 glyphpath->hintOriginY, 1716 FALSE ); 1717 1718 glyphpath->currentCS.x = x; /* pre-offset current point */ 1719 glyphpath->currentCS.y = y; 1720 } 1721 1722 1723 FT_LOCAL_DEF( void ) 1724 cf2_glyphpath_curveTo( CF2_GlyphPath glyphpath, 1725 CF2_Fixed x1, 1726 CF2_Fixed y1, 1727 CF2_Fixed x2, 1728 CF2_Fixed y2, 1729 CF2_Fixed x3, 1730 CF2_Fixed y3 ) 1731 { 1732 CF2_Fixed xOffset1, yOffset1, xOffset3, yOffset3; 1733 FT_Vector P0, P1, P2, P3; 1734 1735 1736 /* TODO: ignore zero length portions of curve?? */ 1737 cf2_glyphpath_computeOffset( glyphpath, 1738 glyphpath->currentCS.x, 1739 glyphpath->currentCS.y, 1740 x1, 1741 y1, 1742 &xOffset1, 1743 &yOffset1 ); 1744 cf2_glyphpath_computeOffset( glyphpath, 1745 x2, 1746 y2, 1747 x3, 1748 y3, 1749 &xOffset3, 1750 &yOffset3 ); 1751 1752 /* add momentum from the middle segment */ 1753 glyphpath->callbacks->windingMomentum += 1754 cf2_getWindingMomentum( x1, y1, x2, y2 ); 1755 1756 /* construct offset points */ 1757 P0.x = glyphpath->currentCS.x + xOffset1; 1758 P0.y = glyphpath->currentCS.y + yOffset1; 1759 P1.x = x1 + xOffset1; 1760 P1.y = y1 + yOffset1; 1761 /* note: preserve angle of final segment by using offset3 at both ends */ 1762 P2.x = x2 + xOffset3; 1763 P2.y = y2 + yOffset3; 1764 P3.x = x3 + xOffset3; 1765 P3.y = y3 + yOffset3; 1766 1767 if ( glyphpath->moveIsPending ) 1768 { 1769 /* emit offset 1st point as MoveTo */ 1770 cf2_glyphpath_pushMove( glyphpath, P0 ); 1771 1772 glyphpath->moveIsPending = FALSE; 1773 glyphpath->pathIsOpen = TRUE; 1774 1775 glyphpath->offsetStart1 = P1; /* record second point */ 1776 } 1777 1778 if ( glyphpath->elemIsQueued ) 1779 { 1780 FT_ASSERT( cf2_hintmap_isValid( &glyphpath->hintMap ) ); 1781 1782 cf2_glyphpath_pushPrevElem( glyphpath, 1783 &glyphpath->hintMap, 1784 &P0, 1785 P1, 1786 FALSE ); 1787 } 1788 1789 /* queue the current element with offset points */ 1790 glyphpath->elemIsQueued = TRUE; 1791 glyphpath->prevElemOp = CF2_PathOpCubeTo; 1792 glyphpath->prevElemP0 = P0; 1793 glyphpath->prevElemP1 = P1; 1794 glyphpath->prevElemP2 = P2; 1795 glyphpath->prevElemP3 = P3; 1796 1797 /* update current map */ 1798 if ( cf2_hintmask_isNew( glyphpath->hintMask ) ) 1799 cf2_hintmap_build( &glyphpath->hintMap, 1800 glyphpath->hStemHintArray, 1801 glyphpath->vStemHintArray, 1802 glyphpath->hintMask, 1803 glyphpath->hintOriginY, 1804 FALSE ); 1805 1806 glyphpath->currentCS.x = x3; /* pre-offset current point */ 1807 glyphpath->currentCS.y = y3; 1808 } 1809 1810 1811 FT_LOCAL_DEF( void ) 1812 cf2_glyphpath_closeOpenPath( CF2_GlyphPath glyphpath ) 1813 { 1814 if ( glyphpath->pathIsOpen ) 1815 { 1816 /* 1817 * A closing line in Character Space line is always generated below 1818 * with `cf2_glyphPath_lineTo'. It may be ignored later if it turns 1819 * out to be zero length in Device Space. 1820 */ 1821 glyphpath->pathIsClosing = TRUE; 1822 1823 cf2_glyphpath_lineTo( glyphpath, 1824 glyphpath->start.x, 1825 glyphpath->start.y ); 1826 1827 /* empty the final element from the queue and close the path */ 1828 if ( glyphpath->elemIsQueued ) 1829 cf2_glyphpath_pushPrevElem( glyphpath, 1830 &glyphpath->hintMap, 1831 &glyphpath->offsetStart0, 1832 glyphpath->offsetStart1, 1833 TRUE ); 1834 1835 /* reset state machine */ 1836 glyphpath->moveIsPending = TRUE; 1837 glyphpath->pathIsOpen = FALSE; 1838 glyphpath->pathIsClosing = FALSE; 1839 glyphpath->elemIsQueued = FALSE; 1840 } 1841 } 1842 1843 1844 /* END */ 1845
