1 /***************************************************************************/ 2 /* */ 3 /* ftoutln.c */ 4 /* */ 5 /* FreeType outline management (body). */ 6 /* */ 7 /* Copyright 1996-2008, 2010, 2012-2013 by */ 8 /* David Turner, Robert Wilhelm, and Werner Lemberg. */ 9 /* */ 10 /* This file is part of the FreeType project, and may only be used, */ 11 /* modified, and distributed under the terms of the FreeType project */ 12 /* license, LICENSE.TXT. By continuing to use, modify, or distribute */ 13 /* this file you indicate that you have read the license and */ 14 /* understand and accept it fully. */ 15 /* */ 16 /***************************************************************************/ 17 18 19 /*************************************************************************/ 20 /* */ 21 /* All functions are declared in freetype.h. */ 22 /* */ 23 /*************************************************************************/ 24 25 26 #include <ft2build.h> 27 #include FT_OUTLINE_H 28 #include FT_INTERNAL_OBJECTS_H 29 #include FT_INTERNAL_CALC_H 30 #include FT_INTERNAL_DEBUG_H 31 #include FT_TRIGONOMETRY_H 32 33 34 /*************************************************************************/ 35 /* */ 36 /* The macro FT_COMPONENT is used in trace mode. It is an implicit */ 37 /* parameter of the FT_TRACE() and FT_ERROR() macros, used to print/log */ 38 /* messages during execution. */ 39 /* */ 40 #undef FT_COMPONENT 41 #define FT_COMPONENT trace_outline 42 43 44 static 45 const FT_Outline null_outline = { 0, 0, 0, 0, 0, 0 }; 46 47 48 /* documentation is in ftoutln.h */ 49 50 FT_EXPORT_DEF( FT_Error ) 51 FT_Outline_Decompose( FT_Outline* outline, 52 const FT_Outline_Funcs* func_interface, 53 void* user ) 54 { 55 #undef SCALED 56 #define SCALED( x ) ( ( (x) << shift ) - delta ) 57 58 FT_Vector v_last; 59 FT_Vector v_control; 60 FT_Vector v_start; 61 62 FT_Vector* point; 63 FT_Vector* limit; 64 char* tags; 65 66 FT_Error error; 67 68 FT_Int n; /* index of contour in outline */ 69 FT_UInt first; /* index of first point in contour */ 70 FT_Int tag; /* current point's state */ 71 72 FT_Int shift; 73 FT_Pos delta; 74 75 76 if ( !outline || !func_interface ) 77 return FT_THROW( Invalid_Argument ); 78 79 shift = func_interface->shift; 80 delta = func_interface->delta; 81 first = 0; 82 83 for ( n = 0; n < outline->n_contours; n++ ) 84 { 85 FT_Int last; /* index of last point in contour */ 86 87 88 FT_TRACE5(( "FT_Outline_Decompose: Outline %d\n", n )); 89 90 last = outline->contours[n]; 91 if ( last < 0 ) 92 goto Invalid_Outline; 93 limit = outline->points + last; 94 95 v_start = outline->points[first]; 96 v_start.x = SCALED( v_start.x ); 97 v_start.y = SCALED( v_start.y ); 98 99 v_last = outline->points[last]; 100 v_last.x = SCALED( v_last.x ); 101 v_last.y = SCALED( v_last.y ); 102 103 v_control = v_start; 104 105 point = outline->points + first; 106 tags = outline->tags + first; 107 tag = FT_CURVE_TAG( tags[0] ); 108 109 /* A contour cannot start with a cubic control point! */ 110 if ( tag == FT_CURVE_TAG_CUBIC ) 111 goto Invalid_Outline; 112 113 /* check first point to determine origin */ 114 if ( tag == FT_CURVE_TAG_CONIC ) 115 { 116 /* first point is conic control. Yes, this happens. */ 117 if ( FT_CURVE_TAG( outline->tags[last] ) == FT_CURVE_TAG_ON ) 118 { 119 /* start at last point if it is on the curve */ 120 v_start = v_last; 121 limit--; 122 } 123 else 124 { 125 /* if both first and last points are conic, */ 126 /* start at their middle and record its position */ 127 /* for closure */ 128 v_start.x = ( v_start.x + v_last.x ) / 2; 129 v_start.y = ( v_start.y + v_last.y ) / 2; 130 131 v_last = v_start; 132 } 133 point--; 134 tags--; 135 } 136 137 FT_TRACE5(( " move to (%.2f, %.2f)\n", 138 v_start.x / 64.0, v_start.y / 64.0 )); 139 error = func_interface->move_to( &v_start, user ); 140 if ( error ) 141 goto Exit; 142 143 while ( point < limit ) 144 { 145 point++; 146 tags++; 147 148 tag = FT_CURVE_TAG( tags[0] ); 149 switch ( tag ) 150 { 151 case FT_CURVE_TAG_ON: /* emit a single line_to */ 152 { 153 FT_Vector vec; 154 155 156 vec.x = SCALED( point->x ); 157 vec.y = SCALED( point->y ); 158 159 FT_TRACE5(( " line to (%.2f, %.2f)\n", 160 vec.x / 64.0, vec.y / 64.0 )); 161 error = func_interface->line_to( &vec, user ); 162 if ( error ) 163 goto Exit; 164 continue; 165 } 166 167 case FT_CURVE_TAG_CONIC: /* consume conic arcs */ 168 v_control.x = SCALED( point->x ); 169 v_control.y = SCALED( point->y ); 170 171 Do_Conic: 172 if ( point < limit ) 173 { 174 FT_Vector vec; 175 FT_Vector v_middle; 176 177 178 point++; 179 tags++; 180 tag = FT_CURVE_TAG( tags[0] ); 181 182 vec.x = SCALED( point->x ); 183 vec.y = SCALED( point->y ); 184 185 if ( tag == FT_CURVE_TAG_ON ) 186 { 187 FT_TRACE5(( " conic to (%.2f, %.2f)" 188 " with control (%.2f, %.2f)\n", 189 vec.x / 64.0, vec.y / 64.0, 190 v_control.x / 64.0, v_control.y / 64.0 )); 191 error = func_interface->conic_to( &v_control, &vec, user ); 192 if ( error ) 193 goto Exit; 194 continue; 195 } 196 197 if ( tag != FT_CURVE_TAG_CONIC ) 198 goto Invalid_Outline; 199 200 v_middle.x = ( v_control.x + vec.x ) / 2; 201 v_middle.y = ( v_control.y + vec.y ) / 2; 202 203 FT_TRACE5(( " conic to (%.2f, %.2f)" 204 " with control (%.2f, %.2f)\n", 205 v_middle.x / 64.0, v_middle.y / 64.0, 206 v_control.x / 64.0, v_control.y / 64.0 )); 207 error = func_interface->conic_to( &v_control, &v_middle, user ); 208 if ( error ) 209 goto Exit; 210 211 v_control = vec; 212 goto Do_Conic; 213 } 214 215 FT_TRACE5(( " conic to (%.2f, %.2f)" 216 " with control (%.2f, %.2f)\n", 217 v_start.x / 64.0, v_start.y / 64.0, 218 v_control.x / 64.0, v_control.y / 64.0 )); 219 error = func_interface->conic_to( &v_control, &v_start, user ); 220 goto Close; 221 222 default: /* FT_CURVE_TAG_CUBIC */ 223 { 224 FT_Vector vec1, vec2; 225 226 227 if ( point + 1 > limit || 228 FT_CURVE_TAG( tags[1] ) != FT_CURVE_TAG_CUBIC ) 229 goto Invalid_Outline; 230 231 point += 2; 232 tags += 2; 233 234 vec1.x = SCALED( point[-2].x ); 235 vec1.y = SCALED( point[-2].y ); 236 237 vec2.x = SCALED( point[-1].x ); 238 vec2.y = SCALED( point[-1].y ); 239 240 if ( point <= limit ) 241 { 242 FT_Vector vec; 243 244 245 vec.x = SCALED( point->x ); 246 vec.y = SCALED( point->y ); 247 248 FT_TRACE5(( " cubic to (%.2f, %.2f)" 249 " with controls (%.2f, %.2f) and (%.2f, %.2f)\n", 250 vec.x / 64.0, vec.y / 64.0, 251 vec1.x / 64.0, vec1.y / 64.0, 252 vec2.x / 64.0, vec2.y / 64.0 )); 253 error = func_interface->cubic_to( &vec1, &vec2, &vec, user ); 254 if ( error ) 255 goto Exit; 256 continue; 257 } 258 259 FT_TRACE5(( " cubic to (%.2f, %.2f)" 260 " with controls (%.2f, %.2f) and (%.2f, %.2f)\n", 261 v_start.x / 64.0, v_start.y / 64.0, 262 vec1.x / 64.0, vec1.y / 64.0, 263 vec2.x / 64.0, vec2.y / 64.0 )); 264 error = func_interface->cubic_to( &vec1, &vec2, &v_start, user ); 265 goto Close; 266 } 267 } 268 } 269 270 /* close the contour with a line segment */ 271 FT_TRACE5(( " line to (%.2f, %.2f)\n", 272 v_start.x / 64.0, v_start.y / 64.0 )); 273 error = func_interface->line_to( &v_start, user ); 274 275 Close: 276 if ( error ) 277 goto Exit; 278 279 first = last + 1; 280 } 281 282 FT_TRACE5(( "FT_Outline_Decompose: Done\n", n )); 283 return FT_Err_Ok; 284 285 Exit: 286 FT_TRACE5(( "FT_Outline_Decompose: Error %d\n", error )); 287 return error; 288 289 Invalid_Outline: 290 return FT_THROW( Invalid_Outline ); 291 } 292 293 294 FT_EXPORT_DEF( FT_Error ) 295 FT_Outline_New_Internal( FT_Memory memory, 296 FT_UInt numPoints, 297 FT_Int numContours, 298 FT_Outline *anoutline ) 299 { 300 FT_Error error; 301 302 303 if ( !anoutline || !memory ) 304 return FT_THROW( Invalid_Argument ); 305 306 *anoutline = null_outline; 307 308 if ( numContours < 0 || 309 (FT_UInt)numContours > numPoints ) 310 return FT_THROW( Invalid_Argument ); 311 312 if ( numPoints > FT_OUTLINE_POINTS_MAX ) 313 return FT_THROW( Array_Too_Large ); 314 315 if ( FT_NEW_ARRAY( anoutline->points, numPoints ) || 316 FT_NEW_ARRAY( anoutline->tags, numPoints ) || 317 FT_NEW_ARRAY( anoutline->contours, numContours ) ) 318 goto Fail; 319 320 anoutline->n_points = (FT_UShort)numPoints; 321 anoutline->n_contours = (FT_Short)numContours; 322 anoutline->flags |= FT_OUTLINE_OWNER; 323 324 return FT_Err_Ok; 325 326 Fail: 327 anoutline->flags |= FT_OUTLINE_OWNER; 328 FT_Outline_Done_Internal( memory, anoutline ); 329 330 return error; 331 } 332 333 334 /* documentation is in ftoutln.h */ 335 336 FT_EXPORT_DEF( FT_Error ) 337 FT_Outline_New( FT_Library library, 338 FT_UInt numPoints, 339 FT_Int numContours, 340 FT_Outline *anoutline ) 341 { 342 if ( !library ) 343 return FT_THROW( Invalid_Library_Handle ); 344 345 return FT_Outline_New_Internal( library->memory, numPoints, 346 numContours, anoutline ); 347 } 348 349 350 /* documentation is in ftoutln.h */ 351 352 FT_EXPORT_DEF( FT_Error ) 353 FT_Outline_Check( FT_Outline* outline ) 354 { 355 if ( outline ) 356 { 357 FT_Int n_points = outline->n_points; 358 FT_Int n_contours = outline->n_contours; 359 FT_Int end0, end; 360 FT_Int n; 361 362 363 /* empty glyph? */ 364 if ( n_points == 0 && n_contours == 0 ) 365 return 0; 366 367 /* check point and contour counts */ 368 if ( n_points <= 0 || n_contours <= 0 ) 369 goto Bad; 370 371 end0 = end = -1; 372 for ( n = 0; n < n_contours; n++ ) 373 { 374 end = outline->contours[n]; 375 376 /* note that we don't accept empty contours */ 377 if ( end <= end0 || end >= n_points ) 378 goto Bad; 379 380 end0 = end; 381 } 382 383 if ( end != n_points - 1 ) 384 goto Bad; 385 386 /* XXX: check the tags array */ 387 return 0; 388 } 389 390 Bad: 391 return FT_THROW( Invalid_Argument ); 392 } 393 394 395 /* documentation is in ftoutln.h */ 396 397 FT_EXPORT_DEF( FT_Error ) 398 FT_Outline_Copy( const FT_Outline* source, 399 FT_Outline *target ) 400 { 401 FT_Int is_owner; 402 403 404 if ( !source || !target || 405 source->n_points != target->n_points || 406 source->n_contours != target->n_contours ) 407 return FT_THROW( Invalid_Argument ); 408 409 if ( source == target ) 410 return FT_Err_Ok; 411 412 FT_ARRAY_COPY( target->points, source->points, source->n_points ); 413 414 FT_ARRAY_COPY( target->tags, source->tags, source->n_points ); 415 416 FT_ARRAY_COPY( target->contours, source->contours, source->n_contours ); 417 418 /* copy all flags, except the `FT_OUTLINE_OWNER' one */ 419 is_owner = target->flags & FT_OUTLINE_OWNER; 420 target->flags = source->flags; 421 422 target->flags &= ~FT_OUTLINE_OWNER; 423 target->flags |= is_owner; 424 425 return FT_Err_Ok; 426 } 427 428 429 FT_EXPORT_DEF( FT_Error ) 430 FT_Outline_Done_Internal( FT_Memory memory, 431 FT_Outline* outline ) 432 { 433 if ( memory && outline ) 434 { 435 if ( outline->flags & FT_OUTLINE_OWNER ) 436 { 437 FT_FREE( outline->points ); 438 FT_FREE( outline->tags ); 439 FT_FREE( outline->contours ); 440 } 441 *outline = null_outline; 442 443 return FT_Err_Ok; 444 } 445 else 446 return FT_THROW( Invalid_Argument ); 447 } 448 449 450 /* documentation is in ftoutln.h */ 451 452 FT_EXPORT_DEF( FT_Error ) 453 FT_Outline_Done( FT_Library library, 454 FT_Outline* outline ) 455 { 456 /* check for valid `outline' in FT_Outline_Done_Internal() */ 457 458 if ( !library ) 459 return FT_THROW( Invalid_Library_Handle ); 460 461 return FT_Outline_Done_Internal( library->memory, outline ); 462 } 463 464 465 /* documentation is in ftoutln.h */ 466 467 FT_EXPORT_DEF( void ) 468 FT_Outline_Get_CBox( const FT_Outline* outline, 469 FT_BBox *acbox ) 470 { 471 FT_Pos xMin, yMin, xMax, yMax; 472 473 474 if ( outline && acbox ) 475 { 476 if ( outline->n_points == 0 ) 477 { 478 xMin = 0; 479 yMin = 0; 480 xMax = 0; 481 yMax = 0; 482 } 483 else 484 { 485 FT_Vector* vec = outline->points; 486 FT_Vector* limit = vec + outline->n_points; 487 488 489 xMin = xMax = vec->x; 490 yMin = yMax = vec->y; 491 vec++; 492 493 for ( ; vec < limit; vec++ ) 494 { 495 FT_Pos x, y; 496 497 498 x = vec->x; 499 if ( x < xMin ) xMin = x; 500 if ( x > xMax ) xMax = x; 501 502 y = vec->y; 503 if ( y < yMin ) yMin = y; 504 if ( y > yMax ) yMax = y; 505 } 506 } 507 acbox->xMin = xMin; 508 acbox->xMax = xMax; 509 acbox->yMin = yMin; 510 acbox->yMax = yMax; 511 } 512 } 513 514 515 /* documentation is in ftoutln.h */ 516 517 FT_EXPORT_DEF( void ) 518 FT_Outline_Translate( const FT_Outline* outline, 519 FT_Pos xOffset, 520 FT_Pos yOffset ) 521 { 522 FT_UShort n; 523 FT_Vector* vec; 524 525 526 if ( !outline ) 527 return; 528 529 vec = outline->points; 530 531 for ( n = 0; n < outline->n_points; n++ ) 532 { 533 vec->x += xOffset; 534 vec->y += yOffset; 535 vec++; 536 } 537 } 538 539 540 /* documentation is in ftoutln.h */ 541 542 FT_EXPORT_DEF( void ) 543 FT_Outline_Reverse( FT_Outline* outline ) 544 { 545 FT_UShort n; 546 FT_Int first, last; 547 548 549 if ( !outline ) 550 return; 551 552 first = 0; 553 554 for ( n = 0; n < outline->n_contours; n++ ) 555 { 556 last = outline->contours[n]; 557 558 /* reverse point table */ 559 { 560 FT_Vector* p = outline->points + first; 561 FT_Vector* q = outline->points + last; 562 FT_Vector swap; 563 564 565 while ( p < q ) 566 { 567 swap = *p; 568 *p = *q; 569 *q = swap; 570 p++; 571 q--; 572 } 573 } 574 575 /* reverse tags table */ 576 { 577 char* p = outline->tags + first; 578 char* q = outline->tags + last; 579 char swap; 580 581 582 while ( p < q ) 583 { 584 swap = *p; 585 *p = *q; 586 *q = swap; 587 p++; 588 q--; 589 } 590 } 591 592 first = last + 1; 593 } 594 595 outline->flags ^= FT_OUTLINE_REVERSE_FILL; 596 } 597 598 599 /* documentation is in ftoutln.h */ 600 601 FT_EXPORT_DEF( FT_Error ) 602 FT_Outline_Render( FT_Library library, 603 FT_Outline* outline, 604 FT_Raster_Params* params ) 605 { 606 FT_Error error; 607 FT_Bool update = FALSE; 608 FT_Renderer renderer; 609 FT_ListNode node; 610 611 612 if ( !library ) 613 return FT_THROW( Invalid_Library_Handle ); 614 615 if ( !outline || !params ) 616 return FT_THROW( Invalid_Argument ); 617 618 renderer = library->cur_renderer; 619 node = library->renderers.head; 620 621 params->source = (void*)outline; 622 623 error = FT_ERR( Cannot_Render_Glyph ); 624 while ( renderer ) 625 { 626 error = renderer->raster_render( renderer->raster, params ); 627 if ( !error || FT_ERR_NEQ( error, Cannot_Render_Glyph ) ) 628 break; 629 630 /* FT_Err_Cannot_Render_Glyph is returned if the render mode */ 631 /* is unsupported by the current renderer for this glyph image */ 632 /* format */ 633 634 /* now, look for another renderer that supports the same */ 635 /* format */ 636 renderer = FT_Lookup_Renderer( library, FT_GLYPH_FORMAT_OUTLINE, 637 &node ); 638 update = TRUE; 639 } 640 641 /* if we changed the current renderer for the glyph image format */ 642 /* we need to select it as the next current one */ 643 if ( !error && update && renderer ) 644 FT_Set_Renderer( library, renderer, 0, 0 ); 645 646 return error; 647 } 648 649 650 /* documentation is in ftoutln.h */ 651 652 FT_EXPORT_DEF( FT_Error ) 653 FT_Outline_Get_Bitmap( FT_Library library, 654 FT_Outline* outline, 655 const FT_Bitmap *abitmap ) 656 { 657 FT_Raster_Params params; 658 659 660 if ( !abitmap ) 661 return FT_THROW( Invalid_Argument ); 662 663 /* other checks are delayed to FT_Outline_Render() */ 664 665 params.target = abitmap; 666 params.flags = 0; 667 668 if ( abitmap->pixel_mode == FT_PIXEL_MODE_GRAY || 669 abitmap->pixel_mode == FT_PIXEL_MODE_LCD || 670 abitmap->pixel_mode == FT_PIXEL_MODE_LCD_V ) 671 params.flags |= FT_RASTER_FLAG_AA; 672 673 return FT_Outline_Render( library, outline, ¶ms ); 674 } 675 676 677 /* documentation is in freetype.h */ 678 679 FT_EXPORT_DEF( void ) 680 FT_Vector_Transform( FT_Vector* vector, 681 const FT_Matrix* matrix ) 682 { 683 FT_Pos xz, yz; 684 685 686 if ( !vector || !matrix ) 687 return; 688 689 xz = FT_MulFix( vector->x, matrix->xx ) + 690 FT_MulFix( vector->y, matrix->xy ); 691 692 yz = FT_MulFix( vector->x, matrix->yx ) + 693 FT_MulFix( vector->y, matrix->yy ); 694 695 vector->x = xz; 696 vector->y = yz; 697 } 698 699 700 /* documentation is in ftoutln.h */ 701 702 FT_EXPORT_DEF( void ) 703 FT_Outline_Transform( const FT_Outline* outline, 704 const FT_Matrix* matrix ) 705 { 706 FT_Vector* vec; 707 FT_Vector* limit; 708 709 710 if ( !outline || !matrix ) 711 return; 712 713 vec = outline->points; 714 limit = vec + outline->n_points; 715 716 for ( ; vec < limit; vec++ ) 717 FT_Vector_Transform( vec, matrix ); 718 } 719 720 721 #if 0 722 723 #define FT_OUTLINE_GET_CONTOUR( outline, c, first, last ) \ 724 do { \ 725 (first) = ( c > 0 ) ? (outline)->points + \ 726 (outline)->contours[c - 1] + 1 \ 727 : (outline)->points; \ 728 (last) = (outline)->points + (outline)->contours[c]; \ 729 } while ( 0 ) 730 731 732 /* Is a point in some contour? */ 733 /* */ 734 /* We treat every point of the contour as if it */ 735 /* it were ON. That is, we allow false positives, */ 736 /* but disallow false negatives. (XXX really?) */ 737 static FT_Bool 738 ft_contour_has( FT_Outline* outline, 739 FT_Short c, 740 FT_Vector* point ) 741 { 742 FT_Vector* first; 743 FT_Vector* last; 744 FT_Vector* a; 745 FT_Vector* b; 746 FT_UInt n = 0; 747 748 749 FT_OUTLINE_GET_CONTOUR( outline, c, first, last ); 750 751 for ( a = first; a <= last; a++ ) 752 { 753 FT_Pos x; 754 FT_Int intersect; 755 756 757 b = ( a == last ) ? first : a + 1; 758 759 intersect = ( a->y - point->y ) ^ ( b->y - point->y ); 760 761 /* a and b are on the same side */ 762 if ( intersect >= 0 ) 763 { 764 if ( intersect == 0 && a->y == point->y ) 765 { 766 if ( ( a->x <= point->x && b->x >= point->x ) || 767 ( a->x >= point->x && b->x <= point->x ) ) 768 return 1; 769 } 770 771 continue; 772 } 773 774 x = a->x + ( b->x - a->x ) * (point->y - a->y ) / ( b->y - a->y ); 775 776 if ( x < point->x ) 777 n++; 778 else if ( x == point->x ) 779 return 1; 780 } 781 782 return n & 1; 783 } 784 785 786 static FT_Bool 787 ft_contour_enclosed( FT_Outline* outline, 788 FT_UShort c ) 789 { 790 FT_Vector* first; 791 FT_Vector* last; 792 FT_Short i; 793 794 795 FT_OUTLINE_GET_CONTOUR( outline, c, first, last ); 796 797 for ( i = 0; i < outline->n_contours; i++ ) 798 { 799 if ( i != c && ft_contour_has( outline, i, first ) ) 800 { 801 FT_Vector* pt; 802 803 804 for ( pt = first + 1; pt <= last; pt++ ) 805 if ( !ft_contour_has( outline, i, pt ) ) 806 return 0; 807 808 return 1; 809 } 810 } 811 812 return 0; 813 } 814 815 816 /* This version differs from the public one in that each */ 817 /* part (contour not enclosed in another contour) of the */ 818 /* outline is checked for orientation. This is */ 819 /* necessary for some buggy CJK fonts. */ 820 static FT_Orientation 821 ft_outline_get_orientation( FT_Outline* outline ) 822 { 823 FT_Short i; 824 FT_Vector* first; 825 FT_Vector* last; 826 FT_Orientation orient = FT_ORIENTATION_NONE; 827 828 829 first = outline->points; 830 for ( i = 0; i < outline->n_contours; i++, first = last + 1 ) 831 { 832 FT_Vector* point; 833 FT_Vector* xmin_point; 834 FT_Pos xmin; 835 836 837 last = outline->points + outline->contours[i]; 838 839 /* skip degenerate contours */ 840 if ( last < first + 2 ) 841 continue; 842 843 if ( ft_contour_enclosed( outline, i ) ) 844 continue; 845 846 xmin = first->x; 847 xmin_point = first; 848 849 for ( point = first + 1; point <= last; point++ ) 850 { 851 if ( point->x < xmin ) 852 { 853 xmin = point->x; 854 xmin_point = point; 855 } 856 } 857 858 /* check the orientation of the contour */ 859 { 860 FT_Vector* prev; 861 FT_Vector* next; 862 FT_Orientation o; 863 864 865 prev = ( xmin_point == first ) ? last : xmin_point - 1; 866 next = ( xmin_point == last ) ? first : xmin_point + 1; 867 868 if ( FT_Atan2( prev->x - xmin_point->x, prev->y - xmin_point->y ) > 869 FT_Atan2( next->x - xmin_point->x, next->y - xmin_point->y ) ) 870 o = FT_ORIENTATION_POSTSCRIPT; 871 else 872 o = FT_ORIENTATION_TRUETYPE; 873 874 if ( orient == FT_ORIENTATION_NONE ) 875 orient = o; 876 else if ( orient != o ) 877 return FT_ORIENTATION_NONE; 878 } 879 } 880 881 return orient; 882 } 883 884 #endif /* 0 */ 885 886 887 /* documentation is in ftoutln.h */ 888 889 FT_EXPORT_DEF( FT_Error ) 890 FT_Outline_Embolden( FT_Outline* outline, 891 FT_Pos strength ) 892 { 893 return FT_Outline_EmboldenXY( outline, strength, strength ); 894 } 895 896 897 /* documentation is in ftoutln.h */ 898 899 FT_EXPORT_DEF( FT_Error ) 900 FT_Outline_EmboldenXY( FT_Outline* outline, 901 FT_Pos xstrength, 902 FT_Pos ystrength ) 903 { 904 FT_Vector* points; 905 FT_Vector v_prev, v_first, v_next, v_cur; 906 FT_Int c, n, first; 907 FT_Int orientation; 908 909 910 if ( !outline ) 911 return FT_THROW( Invalid_Argument ); 912 913 xstrength /= 2; 914 ystrength /= 2; 915 if ( xstrength == 0 && ystrength == 0 ) 916 return FT_Err_Ok; 917 918 orientation = FT_Outline_Get_Orientation( outline ); 919 if ( orientation == FT_ORIENTATION_NONE ) 920 { 921 if ( outline->n_contours ) 922 return FT_THROW( Invalid_Argument ); 923 else 924 return FT_Err_Ok; 925 } 926 927 points = outline->points; 928 929 first = 0; 930 for ( c = 0; c < outline->n_contours; c++ ) 931 { 932 FT_Vector in, out, shift; 933 FT_Fixed l_in, l_out, l, q, d; 934 int last = outline->contours[c]; 935 936 937 v_first = points[first]; 938 v_prev = points[last]; 939 v_cur = v_first; 940 941 /* compute incoming normalized vector */ 942 in.x = v_cur.x - v_prev.x; 943 in.y = v_cur.y - v_prev.y; 944 l_in = FT_Vector_Length( &in ); 945 if ( l_in ) 946 { 947 in.x = FT_DivFix( in.x, l_in ); 948 in.y = FT_DivFix( in.y, l_in ); 949 } 950 951 for ( n = first; n <= last; n++ ) 952 { 953 if ( n < last ) 954 v_next = points[n + 1]; 955 else 956 v_next = v_first; 957 958 /* compute outgoing normalized vector */ 959 out.x = v_next.x - v_cur.x; 960 out.y = v_next.y - v_cur.y; 961 l_out = FT_Vector_Length( &out ); 962 if ( l_out ) 963 { 964 out.x = FT_DivFix( out.x, l_out ); 965 out.y = FT_DivFix( out.y, l_out ); 966 } 967 968 d = FT_MulFix( in.x, out.x ) + FT_MulFix( in.y, out.y ); 969 970 /* shift only if turn is less than ~160 degrees */ 971 if ( d > -0xF000L ) 972 { 973 d = d + 0x10000L; 974 975 /* shift components are aligned along lateral bisector */ 976 /* and directed according to the outline orientation. */ 977 shift.x = in.y + out.y; 978 shift.y = in.x + out.x; 979 980 if ( orientation == FT_ORIENTATION_TRUETYPE ) 981 shift.x = -shift.x; 982 else 983 shift.y = -shift.y; 984 985 /* restrict shift magnitude to better handle collapsing segments */ 986 q = FT_MulFix( out.x, in.y ) - FT_MulFix( out.y, in.x ); 987 if ( orientation == FT_ORIENTATION_TRUETYPE ) 988 q = -q; 989 990 l = FT_MIN( l_in, l_out ); 991 992 /* non-strict inequalities avoid divide-by-zero when q == l == 0 */ 993 if ( FT_MulFix( xstrength, q ) <= FT_MulFix( d, l ) ) 994 shift.x = FT_MulDiv( shift.x, xstrength, d ); 995 else 996 shift.x = FT_MulDiv( shift.x, l, q ); 997 998 999 if ( FT_MulFix( ystrength, q ) <= FT_MulFix( d, l ) ) 1000 shift.y = FT_MulDiv( shift.y, ystrength, d ); 1001 else 1002 shift.y = FT_MulDiv( shift.y, l, q ); 1003 } 1004 else 1005 shift.x = shift.y = 0; 1006 1007 outline->points[n].x = v_cur.x + xstrength + shift.x; 1008 outline->points[n].y = v_cur.y + ystrength + shift.y; 1009 1010 in = out; 1011 l_in = l_out; 1012 v_cur = v_next; 1013 } 1014 1015 first = last + 1; 1016 } 1017 1018 return FT_Err_Ok; 1019 } 1020 1021 1022 /* documentation is in ftoutln.h */ 1023 1024 FT_EXPORT_DEF( FT_Orientation ) 1025 FT_Outline_Get_Orientation( FT_Outline* outline ) 1026 { 1027 FT_BBox cbox; 1028 FT_Int xshift, yshift; 1029 FT_Vector* points; 1030 FT_Vector v_prev, v_cur; 1031 FT_Int c, n, first; 1032 FT_Pos area = 0; 1033 1034 1035 if ( !outline || outline->n_points <= 0 ) 1036 return FT_ORIENTATION_TRUETYPE; 1037 1038 /* We use the nonzero winding rule to find the orientation. */ 1039 /* Since glyph outlines behave much more `regular' than arbitrary */ 1040 /* cubic or quadratic curves, this test deals with the polygon */ 1041 /* only which is spanned up by the control points. */ 1042 1043 FT_Outline_Get_CBox( outline, &cbox ); 1044 1045 xshift = FT_MSB( FT_ABS( cbox.xMax ) | FT_ABS( cbox.xMin ) ) - 14; 1046 xshift = FT_MAX( xshift, 0 ); 1047 1048 yshift = FT_MSB( cbox.yMax - cbox.yMin ) - 14; 1049 yshift = FT_MAX( yshift, 0 ); 1050 1051 points = outline->points; 1052 1053 first = 0; 1054 for ( c = 0; c < outline->n_contours; c++ ) 1055 { 1056 FT_Int last = outline->contours[c]; 1057 1058 1059 v_prev = points[last]; 1060 1061 for ( n = first; n <= last; n++ ) 1062 { 1063 v_cur = points[n]; 1064 area += ( ( v_cur.y - v_prev.y ) >> yshift ) * 1065 ( ( v_cur.x + v_prev.x ) >> xshift ); 1066 v_prev = v_cur; 1067 } 1068 1069 first = last + 1; 1070 } 1071 1072 if ( area > 0 ) 1073 return FT_ORIENTATION_POSTSCRIPT; 1074 else if ( area < 0 ) 1075 return FT_ORIENTATION_TRUETYPE; 1076 else 1077 return FT_ORIENTATION_NONE; 1078 } 1079 1080 1081 /* END */ 1082
