1 /***************************************************************************/
2 /* */
3 /* ftoutln.c */
4 /* */
5 /* FreeType outline management (body). */
6 /* */
7 /* Copyright 1996-2018 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, NULL, NULL, NULL, 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) < 0 ? -( -(x) << shift ) \
57 : ( (x) << shift ) ) - delta )
58
59 FT_Vector v_last;
60 FT_Vector v_control;
61 FT_Vector v_start;
62
63 FT_Vector* point;
64 FT_Vector* limit;
65 char* tags;
66
67 FT_Error error;
68
69 FT_Int n; /* index of contour in outline */
70 FT_UInt first; /* index of first point in contour */
71 FT_Int tag; /* current point's state */
72
73 FT_Int shift;
74 FT_Pos delta;
75
76
77 if ( !outline )
78 return FT_THROW( Invalid_Outline );
79
80 if ( !func_interface )
81 return FT_THROW( Invalid_Argument );
82
83 shift = func_interface->shift;
84 delta = func_interface->delta;
85 first = 0;
86
87 for ( n = 0; n < outline->n_contours; n++ )
88 {
89 FT_Int last; /* index of last point in contour */
90
91
92 FT_TRACE5(( "FT_Outline_Decompose: Outline %d\n", n ));
93
94 last = outline->contours[n];
95 if ( last < 0 )
96 goto Invalid_Outline;
97 limit = outline->points + last;
98
99 v_start = outline->points[first];
100 v_start.x = SCALED( v_start.x );
101 v_start.y = SCALED( v_start.y );
102
103 v_last = outline->points[last];
104 v_last.x = SCALED( v_last.x );
105 v_last.y = SCALED( v_last.y );
106
107 v_control = v_start;
108
109 point = outline->points + first;
110 tags = outline->tags + first;
111 tag = FT_CURVE_TAG( tags[0] );
112
113 /* A contour cannot start with a cubic control point! */
114 if ( tag == FT_CURVE_TAG_CUBIC )
115 goto Invalid_Outline;
116
117 /* check first point to determine origin */
118 if ( tag == FT_CURVE_TAG_CONIC )
119 {
120 /* first point is conic control. Yes, this happens. */
121 if ( FT_CURVE_TAG( outline->tags[last] ) == FT_CURVE_TAG_ON )
122 {
123 /* start at last point if it is on the curve */
124 v_start = v_last;
125 limit--;
126 }
127 else
128 {
129 /* if both first and last points are conic, */
130 /* start at their middle and record its position */
131 /* for closure */
132 v_start.x = ( v_start.x + v_last.x ) / 2;
133 v_start.y = ( v_start.y + v_last.y ) / 2;
134
135 /* v_last = v_start; */
136 }
137 point--;
138 tags--;
139 }
140
141 FT_TRACE5(( " move to (%.2f, %.2f)\n",
142 v_start.x / 64.0, v_start.y / 64.0 ));
143 error = func_interface->move_to( &v_start, user );
144 if ( error )
145 goto Exit;
146
147 while ( point < limit )
148 {
149 point++;
150 tags++;
151
152 tag = FT_CURVE_TAG( tags[0] );
153 switch ( tag )
154 {
155 case FT_CURVE_TAG_ON: /* emit a single line_to */
156 {
157 FT_Vector vec;
158
159
160 vec.x = SCALED( point->x );
161 vec.y = SCALED( point->y );
162
163 FT_TRACE5(( " line to (%.2f, %.2f)\n",
164 vec.x / 64.0, vec.y / 64.0 ));
165 error = func_interface->line_to( &vec, user );
166 if ( error )
167 goto Exit;
168 continue;
169 }
170
171 case FT_CURVE_TAG_CONIC: /* consume conic arcs */
172 v_control.x = SCALED( point->x );
173 v_control.y = SCALED( point->y );
174
175 Do_Conic:
176 if ( point < limit )
177 {
178 FT_Vector vec;
179 FT_Vector v_middle;
180
181
182 point++;
183 tags++;
184 tag = FT_CURVE_TAG( tags[0] );
185
186 vec.x = SCALED( point->x );
187 vec.y = SCALED( point->y );
188
189 if ( tag == FT_CURVE_TAG_ON )
190 {
191 FT_TRACE5(( " conic to (%.2f, %.2f)"
192 " with control (%.2f, %.2f)\n",
193 vec.x / 64.0, vec.y / 64.0,
194 v_control.x / 64.0, v_control.y / 64.0 ));
195 error = func_interface->conic_to( &v_control, &vec, user );
196 if ( error )
197 goto Exit;
198 continue;
199 }
200
201 if ( tag != FT_CURVE_TAG_CONIC )
202 goto Invalid_Outline;
203
204 v_middle.x = ( v_control.x + vec.x ) / 2;
205 v_middle.y = ( v_control.y + vec.y ) / 2;
206
207 FT_TRACE5(( " conic to (%.2f, %.2f)"
208 " with control (%.2f, %.2f)\n",
209 v_middle.x / 64.0, v_middle.y / 64.0,
210 v_control.x / 64.0, v_control.y / 64.0 ));
211 error = func_interface->conic_to( &v_control, &v_middle, user );
212 if ( error )
213 goto Exit;
214
215 v_control = vec;
216 goto Do_Conic;
217 }
218
219 FT_TRACE5(( " conic to (%.2f, %.2f)"
220 " with control (%.2f, %.2f)\n",
221 v_start.x / 64.0, v_start.y / 64.0,
222 v_control.x / 64.0, v_control.y / 64.0 ));
223 error = func_interface->conic_to( &v_control, &v_start, user );
224 goto Close;
225
226 default: /* FT_CURVE_TAG_CUBIC */
227 {
228 FT_Vector vec1, vec2;
229
230
231 if ( point + 1 > limit ||
232 FT_CURVE_TAG( tags[1] ) != FT_CURVE_TAG_CUBIC )
233 goto Invalid_Outline;
234
235 point += 2;
236 tags += 2;
237
238 vec1.x = SCALED( point[-2].x );
239 vec1.y = SCALED( point[-2].y );
240
241 vec2.x = SCALED( point[-1].x );
242 vec2.y = SCALED( point[-1].y );
243
244 if ( point <= limit )
245 {
246 FT_Vector vec;
247
248
249 vec.x = SCALED( point->x );
250 vec.y = SCALED( point->y );
251
252 FT_TRACE5(( " cubic to (%.2f, %.2f)"
253 " with controls (%.2f, %.2f) and (%.2f, %.2f)\n",
254 vec.x / 64.0, vec.y / 64.0,
255 vec1.x / 64.0, vec1.y / 64.0,
256 vec2.x / 64.0, vec2.y / 64.0 ));
257 error = func_interface->cubic_to( &vec1, &vec2, &vec, user );
258 if ( error )
259 goto Exit;
260 continue;
261 }
262
263 FT_TRACE5(( " cubic to (%.2f, %.2f)"
264 " with controls (%.2f, %.2f) and (%.2f, %.2f)\n",
265 v_start.x / 64.0, v_start.y / 64.0,
266 vec1.x / 64.0, vec1.y / 64.0,
267 vec2.x / 64.0, vec2.y / 64.0 ));
268 error = func_interface->cubic_to( &vec1, &vec2, &v_start, user );
269 goto Close;
270 }
271 }
272 }
273
274 /* close the contour with a line segment */
275 FT_TRACE5(( " line to (%.2f, %.2f)\n",
276 v_start.x / 64.0, v_start.y / 64.0 ));
277 error = func_interface->line_to( &v_start, user );
278
279 Close:
280 if ( error )
281 goto Exit;
282
283 first = (FT_UInt)last + 1;
284 }
285
286 FT_TRACE5(( "FT_Outline_Decompose: Done\n", n ));
287 return FT_Err_Ok;
288
289 Exit:
290 FT_TRACE5(( "FT_Outline_Decompose: Error 0x%x\n", error ));
291 return error;
292
293 Invalid_Outline:
294 return FT_THROW( Invalid_Outline );
295 }
296
297
298 FT_EXPORT_DEF( FT_Error )
299 FT_Outline_New_Internal( FT_Memory memory,
300 FT_UInt numPoints,
301 FT_Int numContours,
302 FT_Outline *anoutline )
303 {
304 FT_Error error;
305
306
307 if ( !anoutline || !memory )
308 return FT_THROW( Invalid_Argument );
309
310 *anoutline = null_outline;
311
312 if ( numContours < 0 ||
313 (FT_UInt)numContours > numPoints )
314 return FT_THROW( Invalid_Argument );
315
316 if ( numPoints > FT_OUTLINE_POINTS_MAX )
317 return FT_THROW( Array_Too_Large );
318
319 if ( FT_NEW_ARRAY( anoutline->points, numPoints ) ||
320 FT_NEW_ARRAY( anoutline->tags, numPoints ) ||
321 FT_NEW_ARRAY( anoutline->contours, numContours ) )
322 goto Fail;
323
324 anoutline->n_points = (FT_Short)numPoints;
325 anoutline->n_contours = (FT_Short)numContours;
326 anoutline->flags |= FT_OUTLINE_OWNER;
327
328 return FT_Err_Ok;
329
330 Fail:
331 anoutline->flags |= FT_OUTLINE_OWNER;
332 FT_Outline_Done_Internal( memory, anoutline );
333
334 return error;
335 }
336
337
338 /* documentation is in ftoutln.h */
339
340 FT_EXPORT_DEF( FT_Error )
341 FT_Outline_New( FT_Library library,
342 FT_UInt numPoints,
343 FT_Int numContours,
344 FT_Outline *anoutline )
345 {
346 if ( !library )
347 return FT_THROW( Invalid_Library_Handle );
348
349 return FT_Outline_New_Internal( library->memory, numPoints,
350 numContours, anoutline );
351 }
352
353
354 /* documentation is in ftoutln.h */
355
356 FT_EXPORT_DEF( FT_Error )
357 FT_Outline_Check( FT_Outline* outline )
358 {
359 if ( outline )
360 {
361 FT_Int n_points = outline->n_points;
362 FT_Int n_contours = outline->n_contours;
363 FT_Int end0, end;
364 FT_Int n;
365
366
367 /* empty glyph? */
368 if ( n_points == 0 && n_contours == 0 )
369 return FT_Err_Ok;
370
371 /* check point and contour counts */
372 if ( n_points <= 0 || n_contours <= 0 )
373 goto Bad;
374
375 end0 = end = -1;
376 for ( n = 0; n < n_contours; n++ )
377 {
378 end = outline->contours[n];
379
380 /* note that we don't accept empty contours */
381 if ( end <= end0 || end >= n_points )
382 goto Bad;
383
384 end0 = end;
385 }
386
387 if ( end != n_points - 1 )
388 goto Bad;
389
390 /* XXX: check the tags array */
391 return FT_Err_Ok;
392 }
393
394 Bad:
395 return FT_THROW( Invalid_Argument );
396 }
397
398
399 /* documentation is in ftoutln.h */
400
401 FT_EXPORT_DEF( FT_Error )
402 FT_Outline_Copy( const FT_Outline* source,
403 FT_Outline *target )
404 {
405 FT_Int is_owner;
406
407
408 if ( !source || !target )
409 return FT_THROW( Invalid_Outline );
410
411 if ( source->n_points != target->n_points ||
412 source->n_contours != target->n_contours )
413 return FT_THROW( Invalid_Argument );
414
415 if ( source == target )
416 return FT_Err_Ok;
417
418 if ( source->n_points )
419 {
420 FT_ARRAY_COPY( target->points, source->points, source->n_points );
421 FT_ARRAY_COPY( target->tags, source->tags, source->n_points );
422 }
423
424 if ( source->n_contours )
425 FT_ARRAY_COPY( target->contours, source->contours, source->n_contours );
426
427 /* copy all flags, except the `FT_OUTLINE_OWNER' one */
428 is_owner = target->flags & FT_OUTLINE_OWNER;
429 target->flags = source->flags;
430
431 target->flags &= ~FT_OUTLINE_OWNER;
432 target->flags |= is_owner;
433
434 return FT_Err_Ok;
435 }
436
437
438 FT_EXPORT_DEF( FT_Error )
439 FT_Outline_Done_Internal( FT_Memory memory,
440 FT_Outline* outline )
441 {
442 if ( !outline )
443 return FT_THROW( Invalid_Outline );
444
445 if ( !memory )
446 return FT_THROW( Invalid_Argument );
447
448 if ( outline->flags & FT_OUTLINE_OWNER )
449 {
450 FT_FREE( outline->points );
451 FT_FREE( outline->tags );
452 FT_FREE( outline->contours );
453 }
454 *outline = null_outline;
455
456 return FT_Err_Ok;
457 }
458
459
460 /* documentation is in ftoutln.h */
461
462 FT_EXPORT_DEF( FT_Error )
463 FT_Outline_Done( FT_Library library,
464 FT_Outline* outline )
465 {
466 /* check for valid `outline' in FT_Outline_Done_Internal() */
467
468 if ( !library )
469 return FT_THROW( Invalid_Library_Handle );
470
471 return FT_Outline_Done_Internal( library->memory, outline );
472 }
473
474
475 /* documentation is in ftoutln.h */
476
477 FT_EXPORT_DEF( void )
478 FT_Outline_Get_CBox( const FT_Outline* outline,
479 FT_BBox *acbox )
480 {
481 FT_Pos xMin, yMin, xMax, yMax;
482
483
484 if ( outline && acbox )
485 {
486 if ( outline->n_points == 0 )
487 {
488 xMin = 0;
489 yMin = 0;
490 xMax = 0;
491 yMax = 0;
492 }
493 else
494 {
495 FT_Vector* vec = outline->points;
496 FT_Vector* limit = vec + outline->n_points;
497
498
499 xMin = xMax = vec->x;
500 yMin = yMax = vec->y;
501 vec++;
502
503 for ( ; vec < limit; vec++ )
504 {
505 FT_Pos x, y;
506
507
508 x = vec->x;
509 if ( x < xMin ) xMin = x;
510 if ( x > xMax ) xMax = x;
511
512 y = vec->y;
513 if ( y < yMin ) yMin = y;
514 if ( y > yMax ) yMax = y;
515 }
516 }
517 acbox->xMin = xMin;
518 acbox->xMax = xMax;
519 acbox->yMin = yMin;
520 acbox->yMax = yMax;
521 }
522 }
523
524
525 /* documentation is in ftoutln.h */
526
527 FT_EXPORT_DEF( void )
528 FT_Outline_Translate( const FT_Outline* outline,
529 FT_Pos xOffset,
530 FT_Pos yOffset )
531 {
532 FT_UShort n;
533 FT_Vector* vec;
534
535
536 if ( !outline )
537 return;
538
539 vec = outline->points;
540
541 for ( n = 0; n < outline->n_points; n++ )
542 {
543 vec->x = ADD_LONG( vec->x, xOffset );
544 vec->y = ADD_LONG( vec->y, yOffset );
545 vec++;
546 }
547 }
548
549
550 /* documentation is in ftoutln.h */
551
552 FT_EXPORT_DEF( void )
553 FT_Outline_Reverse( FT_Outline* outline )
554 {
555 FT_UShort n;
556 FT_Int first, last;
557
558
559 if ( !outline )
560 return;
561
562 first = 0;
563
564 for ( n = 0; n < outline->n_contours; n++ )
565 {
566 last = outline->contours[n];
567
568 /* reverse point table */
569 {
570 FT_Vector* p = outline->points + first;
571 FT_Vector* q = outline->points + last;
572 FT_Vector swap;
573
574
575 while ( p < q )
576 {
577 swap = *p;
578 *p = *q;
579 *q = swap;
580 p++;
581 q--;
582 }
583 }
584
585 /* reverse tags table */
586 {
587 char* p = outline->tags + first;
588 char* q = outline->tags + last;
589
590
591 while ( p < q )
592 {
593 char swap;
594
595
596 swap = *p;
597 *p = *q;
598 *q = swap;
599 p++;
600 q--;
601 }
602 }
603
604 first = last + 1;
605 }
606
607 outline->flags ^= FT_OUTLINE_REVERSE_FILL;
608 }
609
610
611 /* documentation is in ftoutln.h */
612
613 FT_EXPORT_DEF( FT_Error )
614 FT_Outline_Render( FT_Library library,
615 FT_Outline* outline,
616 FT_Raster_Params* params )
617 {
618 FT_Error error;
619 FT_Renderer renderer;
620 FT_ListNode node;
621
622
623 if ( !library )
624 return FT_THROW( Invalid_Library_Handle );
625
626 if ( !outline )
627 return FT_THROW( Invalid_Outline );
628
629 if ( !params )
630 return FT_THROW( Invalid_Argument );
631
632 renderer = library->cur_renderer;
633 node = library->renderers.head;
634
635 params->source = (void*)outline;
636
637 error = FT_ERR( Cannot_Render_Glyph );
638 while ( renderer )
639 {
640 error = renderer->raster_render( renderer->raster, params );
641 if ( !error || FT_ERR_NEQ( error, Cannot_Render_Glyph ) )
642 break;
643
644 /* FT_Err_Cannot_Render_Glyph is returned if the render mode */
645 /* is unsupported by the current renderer for this glyph image */
646 /* format */
647
648 /* now, look for another renderer that supports the same */
649 /* format */
650 renderer = FT_Lookup_Renderer( library, FT_GLYPH_FORMAT_OUTLINE,
651 &node );
652 }
653
654 return error;
655 }
656
657
658 /* documentation is in ftoutln.h */
659
660 FT_EXPORT_DEF( FT_Error )
661 FT_Outline_Get_Bitmap( FT_Library library,
662 FT_Outline* outline,
663 const FT_Bitmap *abitmap )
664 {
665 FT_Raster_Params params;
666
667
668 if ( !abitmap )
669 return FT_THROW( Invalid_Argument );
670
671 /* other checks are delayed to `FT_Outline_Render' */
672
673 params.target = abitmap;
674 params.flags = 0;
675
676 if ( abitmap->pixel_mode == FT_PIXEL_MODE_GRAY ||
677 abitmap->pixel_mode == FT_PIXEL_MODE_LCD ||
678 abitmap->pixel_mode == FT_PIXEL_MODE_LCD_V )
679 params.flags |= FT_RASTER_FLAG_AA;
680
681 return FT_Outline_Render( library, outline, ¶ms );
682 }
683
684
685 /* documentation is in freetype.h */
686
687 FT_EXPORT_DEF( void )
688 FT_Vector_Transform( FT_Vector* vector,
689 const FT_Matrix* matrix )
690 {
691 FT_Pos xz, yz;
692
693
694 if ( !vector || !matrix )
695 return;
696
697 xz = FT_MulFix( vector->x, matrix->xx ) +
698 FT_MulFix( vector->y, matrix->xy );
699
700 yz = FT_MulFix( vector->x, matrix->yx ) +
701 FT_MulFix( vector->y, matrix->yy );
702
703 vector->x = xz;
704 vector->y = yz;
705 }
706
707
708 /* documentation is in ftoutln.h */
709
710 FT_EXPORT_DEF( void )
711 FT_Outline_Transform( const FT_Outline* outline,
712 const FT_Matrix* matrix )
713 {
714 FT_Vector* vec;
715 FT_Vector* limit;
716
717
718 if ( !outline || !matrix )
719 return;
720
721 vec = outline->points;
722 limit = vec + outline->n_points;
723
724 for ( ; vec < limit; vec++ )
725 FT_Vector_Transform( vec, matrix );
726 }
727
728
729 #if 0
730
731 #define FT_OUTLINE_GET_CONTOUR( outline, c, first, last ) \
732 do \
733 { \
734 (first) = ( c > 0 ) ? (outline)->points + \
735 (outline)->contours[c - 1] + 1 \
736 : (outline)->points; \
737 (last) = (outline)->points + (outline)->contours[c]; \
738 } while ( 0 )
739
740
741 /* Is a point in some contour? */
742 /* */
743 /* We treat every point of the contour as if it */
744 /* it were ON. That is, we allow false positives, */
745 /* but disallow false negatives. (XXX really?) */
746 static FT_Bool
747 ft_contour_has( FT_Outline* outline,
748 FT_Short c,
749 FT_Vector* point )
750 {
751 FT_Vector* first;
752 FT_Vector* last;
753 FT_Vector* a;
754 FT_Vector* b;
755 FT_UInt n = 0;
756
757
758 FT_OUTLINE_GET_CONTOUR( outline, c, first, last );
759
760 for ( a = first; a <= last; a++ )
761 {
762 FT_Pos x;
763 FT_Int intersect;
764
765
766 b = ( a == last ) ? first : a + 1;
767
768 intersect = ( a->y - point->y ) ^ ( b->y - point->y );
769
770 /* a and b are on the same side */
771 if ( intersect >= 0 )
772 {
773 if ( intersect == 0 && a->y == point->y )
774 {
775 if ( ( a->x <= point->x && b->x >= point->x ) ||
776 ( a->x >= point->x && b->x <= point->x ) )
777 return 1;
778 }
779
780 continue;
781 }
782
783 x = a->x + ( b->x - a->x ) * (point->y - a->y ) / ( b->y - a->y );
784
785 if ( x < point->x )
786 n++;
787 else if ( x == point->x )
788 return 1;
789 }
790
791 return n & 1;
792 }
793
794
795 static FT_Bool
796 ft_contour_enclosed( FT_Outline* outline,
797 FT_UShort c )
798 {
799 FT_Vector* first;
800 FT_Vector* last;
801 FT_Short i;
802
803
804 FT_OUTLINE_GET_CONTOUR( outline, c, first, last );
805
806 for ( i = 0; i < outline->n_contours; i++ )
807 {
808 if ( i != c && ft_contour_has( outline, i, first ) )
809 {
810 FT_Vector* pt;
811
812
813 for ( pt = first + 1; pt <= last; pt++ )
814 if ( !ft_contour_has( outline, i, pt ) )
815 return 0;
816
817 return 1;
818 }
819 }
820
821 return 0;
822 }
823
824
825 /* This version differs from the public one in that each */
826 /* part (contour not enclosed in another contour) of the */
827 /* outline is checked for orientation. This is */
828 /* necessary for some buggy CJK fonts. */
829 static FT_Orientation
830 ft_outline_get_orientation( FT_Outline* outline )
831 {
832 FT_Short i;
833 FT_Vector* first;
834 FT_Vector* last;
835 FT_Orientation orient = FT_ORIENTATION_NONE;
836
837
838 first = outline->points;
839 for ( i = 0; i < outline->n_contours; i++, first = last + 1 )
840 {
841 FT_Vector* point;
842 FT_Vector* xmin_point;
843 FT_Pos xmin;
844
845
846 last = outline->points + outline->contours[i];
847
848 /* skip degenerate contours */
849 if ( last < first + 2 )
850 continue;
851
852 if ( ft_contour_enclosed( outline, i ) )
853 continue;
854
855 xmin = first->x;
856 xmin_point = first;
857
858 for ( point = first + 1; point <= last; point++ )
859 {
860 if ( point->x < xmin )
861 {
862 xmin = point->x;
863 xmin_point = point;
864 }
865 }
866
867 /* check the orientation of the contour */
868 {
869 FT_Vector* prev;
870 FT_Vector* next;
871 FT_Orientation o;
872
873
874 prev = ( xmin_point == first ) ? last : xmin_point - 1;
875 next = ( xmin_point == last ) ? first : xmin_point + 1;
876
877 if ( FT_Atan2( prev->x - xmin_point->x, prev->y - xmin_point->y ) >
878 FT_Atan2( next->x - xmin_point->x, next->y - xmin_point->y ) )
879 o = FT_ORIENTATION_POSTSCRIPT;
880 else
881 o = FT_ORIENTATION_TRUETYPE;
882
883 if ( orient == FT_ORIENTATION_NONE )
884 orient = o;
885 else if ( orient != o )
886 return FT_ORIENTATION_NONE;
887 }
888 }
889
890 return orient;
891 }
892
893 #endif /* 0 */
894
895
896 /* documentation is in ftoutln.h */
897
898 FT_EXPORT_DEF( FT_Error )
899 FT_Outline_Embolden( FT_Outline* outline,
900 FT_Pos strength )
901 {
902 return FT_Outline_EmboldenXY( outline, strength, strength );
903 }
904
905
906 /* documentation is in ftoutln.h */
907
908 FT_EXPORT_DEF( FT_Error )
909 FT_Outline_EmboldenXY( FT_Outline* outline,
910 FT_Pos xstrength,
911 FT_Pos ystrength )
912 {
913 FT_Vector* points;
914 FT_Int c, first, last;
915 FT_Int orientation;
916
917
918 if ( !outline )
919 return FT_THROW( Invalid_Outline );
920
921 xstrength /= 2;
922 ystrength /= 2;
923 if ( xstrength == 0 && ystrength == 0 )
924 return FT_Err_Ok;
925
926 orientation = FT_Outline_Get_Orientation( outline );
927 if ( orientation == FT_ORIENTATION_NONE )
928 {
929 if ( outline->n_contours )
930 return FT_THROW( Invalid_Argument );
931 else
932 return FT_Err_Ok;
933 }
934
935 points = outline->points;
936
937 first = 0;
938 for ( c = 0; c < outline->n_contours; c++ )
939 {
940 FT_Vector in, out, anchor, shift;
941 FT_Fixed l_in, l_out, l_anchor = 0, l, q, d;
942 FT_Int i, j, k;
943
944
945 l_in = 0;
946 last = outline->contours[c];
947
948 /* pacify compiler */
949 in.x = in.y = anchor.x = anchor.y = 0;
950
951 /* Counter j cycles though the points; counter i advances only */
952 /* when points are moved; anchor k marks the first moved point. */
953 for ( i = last, j = first, k = -1;
954 j != i && i != k;
955 j = j < last ? j + 1 : first )
956 {
957 if ( j != k )
958 {
959 out.x = points[j].x - points[i].x;
960 out.y = points[j].y - points[i].y;
961 l_out = (FT_Fixed)FT_Vector_NormLen( &out );
962
963 if ( l_out == 0 )
964 continue;
965 }
966 else
967 {
968 out = anchor;
969 l_out = l_anchor;
970 }
971
972 if ( l_in != 0 )
973 {
974 if ( k < 0 )
975 {
976 k = i;
977 anchor = in;
978 l_anchor = l_in;
979 }
980
981 d = FT_MulFix( in.x, out.x ) + FT_MulFix( in.y, out.y );
982
983 /* shift only if turn is less than ~160 degrees */
984 if ( d > -0xF000L )
985 {
986 d = d + 0x10000L;
987
988 /* shift components along lateral bisector in proper orientation */
989 shift.x = in.y + out.y;
990 shift.y = in.x + out.x;
991
992 if ( orientation == FT_ORIENTATION_TRUETYPE )
993 shift.x = -shift.x;
994 else
995 shift.y = -shift.y;
996
997 /* restrict shift magnitude to better handle collapsing segments */
998 q = FT_MulFix( out.x, in.y ) - FT_MulFix( out.y, in.x );
999 if ( orientation == FT_ORIENTATION_TRUETYPE )
1000 q = -q;
1001
1002 l = FT_MIN( l_in, l_out );
1003
1004 /* non-strict inequalities avoid divide-by-zero when q == l == 0 */
1005 if ( FT_MulFix( xstrength, q ) <= FT_MulFix( l, d ) )
1006 shift.x = FT_MulDiv( shift.x, xstrength, d );
1007 else
1008 shift.x = FT_MulDiv( shift.x, l, q );
1009
1010
1011 if ( FT_MulFix( ystrength, q ) <= FT_MulFix( l, d ) )
1012 shift.y = FT_MulDiv( shift.y, ystrength, d );
1013 else
1014 shift.y = FT_MulDiv( shift.y, l, q );
1015 }
1016 else
1017 shift.x = shift.y = 0;
1018
1019 for ( ;
1020 i != j;
1021 i = i < last ? i + 1 : first )
1022 {
1023 points[i].x += xstrength + shift.x;
1024 points[i].y += ystrength + shift.y;
1025 }
1026 }
1027 else
1028 i = j;
1029
1030 in = out;
1031 l_in = l_out;
1032 }
1033
1034 first = last + 1;
1035 }
1036
1037 return FT_Err_Ok;
1038 }
1039
1040
1041 /* documentation is in ftoutln.h */
1042
1043 FT_EXPORT_DEF( FT_Orientation )
1044 FT_Outline_Get_Orientation( FT_Outline* outline )
1045 {
1046 FT_BBox cbox;
1047 FT_Int xshift, yshift;
1048 FT_Vector* points;
1049 FT_Vector v_prev, v_cur;
1050 FT_Int c, n, first;
1051 FT_Pos area = 0;
1052
1053
1054 if ( !outline || outline->n_points <= 0 )
1055 return FT_ORIENTATION_TRUETYPE;
1056
1057 /* We use the nonzero winding rule to find the orientation. */
1058 /* Since glyph outlines behave much more `regular' than arbitrary */
1059 /* cubic or quadratic curves, this test deals with the polygon */
1060 /* only that is spanned up by the control points. */
1061
1062 FT_Outline_Get_CBox( outline, &cbox );
1063
1064 /* Handle collapsed outlines to avoid undefined FT_MSB. */
1065 if ( cbox.xMin == cbox.xMax || cbox.yMin == cbox.yMax )
1066 return FT_ORIENTATION_NONE;
1067
1068 xshift = FT_MSB( (FT_UInt32)( FT_ABS( cbox.xMax ) |
1069 FT_ABS( cbox.xMin ) ) ) - 14;
1070 xshift = FT_MAX( xshift, 0 );
1071
1072 yshift = FT_MSB( (FT_UInt32)( cbox.yMax - cbox.yMin ) ) - 14;
1073 yshift = FT_MAX( yshift, 0 );
1074
1075 points = outline->points;
1076
1077 first = 0;
1078 for ( c = 0; c < outline->n_contours; c++ )
1079 {
1080 FT_Int last = outline->contours[c];
1081
1082
1083 v_prev.x = points[last].x >> xshift;
1084 v_prev.y = points[last].y >> yshift;
1085
1086 for ( n = first; n <= last; n++ )
1087 {
1088 v_cur.x = points[n].x >> xshift;
1089 v_cur.y = points[n].y >> yshift;
1090
1091 area = ADD_LONG( area,
1092 ( v_cur.y - v_prev.y ) * ( v_cur.x + v_prev.x ) );
1093
1094 v_prev = v_cur;
1095 }
1096
1097 first = last + 1;
1098 }
1099
1100 if ( area > 0 )
1101 return FT_ORIENTATION_POSTSCRIPT;
1102 else if ( area < 0 )
1103 return FT_ORIENTATION_TRUETYPE;
1104 else
1105 return FT_ORIENTATION_NONE;
1106 }
1107
1108
1109 /* END */