1 /****************************************************************************
2 *
3 * afhints.c
4 *
5 * Auto-fitter hinting routines (body).
6 *
7 * Copyright (C) 2003-2023 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 #include "afhints.h"
20 #include "aferrors.h"
21 #include <freetype/internal/ftcalc.h>
22 #include <freetype/internal/ftdebug.h>
23
24
25 /**************************************************************************
26 *
27 * The macro FT_COMPONENT is used in trace mode. It is an implicit
28 * parameter of the FT_TRACE() and FT_ERROR() macros, used to print/log
29 * messages during execution.
30 */
31 #undef FT_COMPONENT
32 #define FT_COMPONENT afhints
33
34
35 FT_LOCAL_DEF( void )
36 af_sort_pos( FT_UInt count,
37 FT_Pos* table )
38 {
39 FT_UInt i, j;
40 FT_Pos swap;
41
42
43 for ( i = 1; i < count; i++ )
44 {
45 for ( j = i; j > 0; j-- )
46 {
47 if ( table[j] >= table[j - 1] )
48 break;
49
50 swap = table[j];
51 table[j] = table[j - 1];
52 table[j - 1] = swap;
53 }
54 }
55 }
56
57
58 FT_LOCAL_DEF( void )
59 af_sort_and_quantize_widths( FT_UInt* count,
60 AF_Width table,
61 FT_Pos threshold )
62 {
63 FT_UInt i, j;
64 FT_UInt cur_idx;
65 FT_Pos cur_val;
66 FT_Pos sum;
67 AF_WidthRec swap;
68
69
70 if ( *count == 1 )
71 return;
72
73 /* sort */
74 for ( i = 1; i < *count; i++ )
75 {
76 for ( j = i; j > 0; j-- )
77 {
78 if ( table[j].org >= table[j - 1].org )
79 break;
80
81 swap = table[j];
82 table[j] = table[j - 1];
83 table[j - 1] = swap;
84 }
85 }
86
87 cur_idx = 0;
88 cur_val = table[cur_idx].org;
89
90 /* compute and use mean values for clusters not larger than */
91 /* `threshold'; this is very primitive and might not yield */
92 /* the best result, but normally, using reference character */
93 /* `o', `*count' is 2, so the code below is fully sufficient */
94 for ( i = 1; i < *count; i++ )
95 {
96 if ( table[i].org - cur_val > threshold ||
97 i == *count - 1 )
98 {
99 sum = 0;
100
101 /* fix loop for end of array */
102 if ( table[i].org - cur_val <= threshold &&
103 i == *count - 1 )
104 i++;
105
106 for ( j = cur_idx; j < i; j++ )
107 {
108 sum += table[j].org;
109 table[j].org = 0;
110 }
111 table[cur_idx].org = sum / (FT_Pos)j;
112
113 if ( i < *count - 1 )
114 {
115 cur_idx = i + 1;
116 cur_val = table[cur_idx].org;
117 }
118 }
119 }
120
121 cur_idx = 1;
122
123 /* compress array to remove zero values */
124 for ( i = 1; i < *count; i++ )
125 {
126 if ( table[i].org )
127 table[cur_idx++] = table[i];
128 }
129
130 *count = cur_idx;
131 }
132
133 /* Get new segment for given axis. */
134
135 FT_LOCAL_DEF( FT_Error )
136 af_axis_hints_new_segment( AF_AxisHints axis,
137 FT_Memory memory,
138 AF_Segment *asegment )
139 {
140 FT_Error error = FT_Err_Ok;
141 AF_Segment segment = NULL;
142
143
144 if ( axis->num_segments < AF_SEGMENTS_EMBEDDED )
145 {
146 if ( !axis->segments )
147 {
148 axis->segments = axis->embedded.segments;
149 axis->max_segments = AF_SEGMENTS_EMBEDDED;
150 }
151 }
152 else if ( axis->num_segments >= axis->max_segments )
153 {
154 FT_UInt old_max = axis->max_segments;
155 FT_UInt new_max = old_max;
156 FT_UInt big_max = FT_INT_MAX / sizeof ( *segment );
157
158
159 if ( old_max >= big_max )
160 {
161 error = FT_THROW( Out_Of_Memory );
162 goto Exit;
163 }
164
165 new_max += ( new_max >> 2 ) + 4;
166 if ( new_max < old_max || new_max > big_max )
167 new_max = big_max;
168
169 if ( axis->segments == axis->embedded.segments )
170 {
171 if ( FT_NEW_ARRAY( axis->segments, new_max ) )
172 goto Exit;
173 ft_memcpy( axis->segments, axis->embedded.segments,
174 sizeof ( axis->embedded.segments ) );
175 }
176 else
177 {
178 if ( FT_RENEW_ARRAY( axis->segments, old_max, new_max ) )
179 goto Exit;
180 }
181
182 axis->max_segments = new_max;
183 }
184
185 segment = axis->segments + axis->num_segments++;
186
187 Exit:
188 *asegment = segment;
189 return error;
190 }
191
192
193 /* Get new edge for given axis, direction, and position, */
194 /* without initializing the edge itself. */
195
196 FT_LOCAL_DEF( FT_Error )
197 af_axis_hints_new_edge( AF_AxisHints axis,
198 FT_Int fpos,
199 AF_Direction dir,
200 FT_Bool top_to_bottom_hinting,
201 FT_Memory memory,
202 AF_Edge *anedge )
203 {
204 FT_Error error = FT_Err_Ok;
205 AF_Edge edge = NULL;
206 AF_Edge edges;
207
208
209 if ( axis->num_edges < AF_EDGES_EMBEDDED )
210 {
211 if ( !axis->edges )
212 {
213 axis->edges = axis->embedded.edges;
214 axis->max_edges = AF_EDGES_EMBEDDED;
215 }
216 }
217 else if ( axis->num_edges >= axis->max_edges )
218 {
219 FT_UInt old_max = axis->max_edges;
220 FT_UInt new_max = old_max;
221 FT_UInt big_max = FT_INT_MAX / sizeof ( *edge );
222
223
224 if ( old_max >= big_max )
225 {
226 error = FT_THROW( Out_Of_Memory );
227 goto Exit;
228 }
229
230 new_max += ( new_max >> 2 ) + 4;
231 if ( new_max < old_max || new_max > big_max )
232 new_max = big_max;
233
234 if ( axis->edges == axis->embedded.edges )
235 {
236 if ( FT_NEW_ARRAY( axis->edges, new_max ) )
237 goto Exit;
238 ft_memcpy( axis->edges, axis->embedded.edges,
239 sizeof ( axis->embedded.edges ) );
240 }
241 else
242 {
243 if ( FT_RENEW_ARRAY( axis->edges, old_max, new_max ) )
244 goto Exit;
245 }
246
247 axis->max_edges = new_max;
248 }
249
250 edges = axis->edges;
251 edge = edges + axis->num_edges;
252
253 while ( edge > edges )
254 {
255 if ( top_to_bottom_hinting ? ( edge[-1].fpos > fpos )
256 : ( edge[-1].fpos < fpos ) )
257 break;
258
259 /* we want the edge with same position and minor direction */
260 /* to appear before those in the major one in the list */
261 if ( edge[-1].fpos == fpos && dir == axis->major_dir )
262 break;
263
264 edge[0] = edge[-1];
265 edge--;
266 }
267
268 axis->num_edges++;
269
270 Exit:
271 *anedge = edge;
272 return error;
273 }
274
275
276 #ifdef FT_DEBUG_AUTOFIT
277
278 #include FT_CONFIG_STANDARD_LIBRARY_H
279
280 /* The dump functions are used in the `ftgrid' demo program, too. */
281 #define AF_DUMP( varformat ) \
282 do \
283 { \
284 if ( to_stdout ) \
285 printf varformat; \
286 else \
287 FT_TRACE7( varformat ); \
288 } while ( 0 )
289
290
291 static const char*
292 af_dir_str( AF_Direction dir )
293 {
294 const char* result;
295
296
297 switch ( dir )
298 {
299 case AF_DIR_UP:
300 result = "up";
301 break;
302 case AF_DIR_DOWN:
303 result = "down";
304 break;
305 case AF_DIR_LEFT:
306 result = "left";
307 break;
308 case AF_DIR_RIGHT:
309 result = "right";
310 break;
311 default:
312 result = "none";
313 }
314
315 return result;
316 }
317
318
319 #define AF_INDEX_NUM( ptr, base ) (int)( (ptr) ? ( (ptr) - (base) ) : -1 )
320
321
322 static char*
323 af_print_idx( char* p,
324 size_t n,
325 int idx )
326 {
327 if ( idx == -1 )
328 {
329 p[0] = '-';
330 p[1] = '-';
331 p[2] = '\0';
332 }
333 else
334 ft_snprintf( p, n, "%d", idx );
335
336 return p;
337 }
338
339
340 static int
341 af_get_segment_index( AF_GlyphHints hints,
342 int point_idx,
343 int dimension )
344 {
345 AF_AxisHints axis = &hints->axis[dimension];
346 AF_Point point = hints->points + point_idx;
347 AF_Segment segments = axis->segments;
348 AF_Segment limit = segments + axis->num_segments;
349 AF_Segment segment;
350
351
352 for ( segment = segments; segment < limit; segment++ )
353 {
354 if ( segment->first <= segment->last )
355 {
356 if ( point >= segment->first && point <= segment->last )
357 break;
358 }
359 else
360 {
361 AF_Point p = segment->first;
362
363
364 for (;;)
365 {
366 if ( point == p )
367 goto Exit;
368
369 if ( p == segment->last )
370 break;
371
372 p = p->next;
373 }
374 }
375 }
376
377 Exit:
378 if ( segment == limit )
379 return -1;
380
381 return (int)( segment - segments );
382 }
383
384
385 static int
386 af_get_edge_index( AF_GlyphHints hints,
387 int segment_idx,
388 int dimension )
389 {
390 AF_AxisHints axis = &hints->axis[dimension];
391 AF_Edge edges = axis->edges;
392 AF_Segment segment = axis->segments + segment_idx;
393
394
395 return segment_idx == -1 ? -1 : AF_INDEX_NUM( segment->edge, edges );
396 }
397
398
399 static int
400 af_get_strong_edge_index( AF_GlyphHints hints,
401 AF_Edge* strong_edges,
402 int dimension )
403 {
404 AF_AxisHints axis = &hints->axis[dimension];
405 AF_Edge edges = axis->edges;
406
407
408 return AF_INDEX_NUM( strong_edges[dimension], edges );
409 }
410
411
412 #ifdef __cplusplus
413 extern "C" {
414 #endif
415 void
416 af_glyph_hints_dump_points( AF_GlyphHints hints,
417 FT_Bool to_stdout )
418 {
419 AF_Point points = hints->points;
420 AF_Point limit = points + hints->num_points;
421 AF_Point* contour = hints->contours;
422 AF_Point* climit = contour + hints->num_contours;
423 AF_Point point;
424
425
426 AF_DUMP(( "Table of points:\n" ));
427
428 if ( hints->num_points )
429 {
430 AF_DUMP(( " index hedge hseg vedge vseg flags "
431 /* " XXXXX XXXXX XXXXX XXXXX XXXXX XXXXXX" */
432 " xorg yorg xscale yscale xfit yfit "
433 /* " XXXXX XXXXX XXXX.XX XXXX.XX XXXX.XX XXXX.XX" */
434 " hbef haft vbef vaft" ));
435 /* " XXXXX XXXXX XXXXX XXXXX" */
436 }
437 else
438 AF_DUMP(( " (none)\n" ));
439
440 for ( point = points; point < limit; point++ )
441 {
442 int point_idx = AF_INDEX_NUM( point, points );
443 int segment_idx_0 = af_get_segment_index( hints, point_idx, 0 );
444 int segment_idx_1 = af_get_segment_index( hints, point_idx, 1 );
445
446 char buf1[16], buf2[16], buf3[16], buf4[16];
447 char buf5[16], buf6[16], buf7[16], buf8[16];
448
449
450 /* insert extra newline at the beginning of a contour */
451 if ( contour < climit && *contour == point )
452 {
453 AF_DUMP(( "\n" ));
454 contour++;
455 }
456
457 AF_DUMP(( " %5d %5s %5s %5s %5s %s"
458 " %5d %5d %7.2f %7.2f %7.2f %7.2f"
459 " %5s %5s %5s %5s\n",
460 point_idx,
461 af_print_idx( buf1, 16,
462 af_get_edge_index( hints, segment_idx_1, 1 ) ),
463 af_print_idx( buf2, 16, segment_idx_1 ),
464 af_print_idx( buf3, 16,
465 af_get_edge_index( hints, segment_idx_0, 0 ) ),
466 af_print_idx( buf4, 16, segment_idx_0 ),
467 ( point->flags & AF_FLAG_NEAR )
468 ? " near "
469 : ( point->flags & AF_FLAG_WEAK_INTERPOLATION )
470 ? " weak "
471 : "strong",
472
473 point->fx,
474 point->fy,
475 (double)point->ox / 64,
476 (double)point->oy / 64,
477 (double)point->x / 64,
478 (double)point->y / 64,
479
480 af_print_idx( buf5, 16,
481 af_get_strong_edge_index( hints,
482 point->before,
483 1 ) ),
484 af_print_idx( buf6, 16,
485 af_get_strong_edge_index( hints,
486 point->after,
487 1 ) ),
488 af_print_idx( buf7, 16,
489 af_get_strong_edge_index( hints,
490 point->before,
491 0 ) ),
492 af_print_idx( buf8, 16,
493 af_get_strong_edge_index( hints,
494 point->after,
495 0 ) ) ));
496 }
497 AF_DUMP(( "\n" ));
498 }
499 #ifdef __cplusplus
500 }
501 #endif
502
503
504 static const char*
505 af_edge_flags_to_string( FT_UInt flags )
506 {
507 static char temp[32];
508 int pos = 0;
509
510
511 if ( flags & AF_EDGE_ROUND )
512 {
513 ft_memcpy( temp + pos, "round", 5 );
514 pos += 5;
515 }
516 if ( flags & AF_EDGE_SERIF )
517 {
518 if ( pos > 0 )
519 temp[pos++] = ' ';
520 ft_memcpy( temp + pos, "serif", 5 );
521 pos += 5;
522 }
523 if ( pos == 0 )
524 return "normal";
525
526 temp[pos] = '\0';
527
528 return temp;
529 }
530
531
532 /* Dump the array of linked segments. */
533
534 #ifdef __cplusplus
535 extern "C" {
536 #endif
537 void
538 af_glyph_hints_dump_segments( AF_GlyphHints hints,
539 FT_Bool to_stdout )
540 {
541 FT_Int dimension;
542
543
544 for ( dimension = 1; dimension >= 0; dimension-- )
545 {
546 AF_AxisHints axis = &hints->axis[dimension];
547 AF_Point points = hints->points;
548 AF_Edge edges = axis->edges;
549 AF_Segment segments = axis->segments;
550 AF_Segment limit = segments + axis->num_segments;
551 AF_Segment seg;
552
553 char buf1[16], buf2[16], buf3[16];
554
555
556 AF_DUMP(( "Table of %s segments:\n",
557 dimension == AF_DIMENSION_HORZ ? "vertical"
558 : "horizontal" ));
559 if ( axis->num_segments )
560 {
561 AF_DUMP(( " index pos delta dir from to "
562 /* " XXXXX XXXXX XXXXX XXXXX XXXX XXXX" */
563 " link serif edge"
564 /* " XXXX XXXXX XXXX" */
565 " height extra flags\n" ));
566 /* " XXXXXX XXXXX XXXXXXXXXXX" */
567 }
568 else
569 AF_DUMP(( " (none)\n" ));
570
571 for ( seg = segments; seg < limit; seg++ )
572 AF_DUMP(( " %5d %5d %5d %5s %4d %4d"
573 " %4s %5s %4s"
574 " %6d %5d %11s\n",
575 AF_INDEX_NUM( seg, segments ),
576 seg->pos,
577 seg->delta,
578 af_dir_str( (AF_Direction)seg->dir ),
579 AF_INDEX_NUM( seg->first, points ),
580 AF_INDEX_NUM( seg->last, points ),
581
582 af_print_idx( buf1, 16,
583 AF_INDEX_NUM( seg->link, segments ) ),
584 af_print_idx( buf2, 16,
585 AF_INDEX_NUM( seg->serif, segments ) ),
586 af_print_idx( buf3, 16,
587 AF_INDEX_NUM( seg->edge, edges ) ),
588
589 seg->height,
590 seg->height - ( seg->max_coord - seg->min_coord ),
591 af_edge_flags_to_string( seg->flags ) ));
592 AF_DUMP(( "\n" ));
593 }
594 }
595 #ifdef __cplusplus
596 }
597 #endif
598
599
600 /* Fetch number of segments. */
601
602 #ifdef __cplusplus
603 extern "C" {
604 #endif
605 FT_Error
606 af_glyph_hints_get_num_segments( AF_GlyphHints hints,
607 FT_Int dimension,
608 FT_UInt* num_segments )
609 {
610 AF_Dimension dim;
611 AF_AxisHints axis;
612
613
614 dim = ( dimension == 0 ) ? AF_DIMENSION_HORZ : AF_DIMENSION_VERT;
615
616 axis = &hints->axis[dim];
617 *num_segments = axis->num_segments;
618
619 return FT_Err_Ok;
620 }
621 #ifdef __cplusplus
622 }
623 #endif
624
625
626 /* Fetch offset of segments into user supplied offset array. */
627
628 #ifdef __cplusplus
629 extern "C" {
630 #endif
631 FT_Error
632 af_glyph_hints_get_segment_offset( AF_GlyphHints hints,
633 FT_Int dimension,
634 FT_UInt idx,
635 FT_Pos *offset,
636 FT_Bool *is_blue,
637 FT_Pos *blue_offset )
638 {
639 AF_Dimension dim;
640 AF_AxisHints axis;
641 AF_Segment seg;
642
643
644 if ( !offset )
645 return FT_THROW( Invalid_Argument );
646
647 dim = ( dimension == 0 ) ? AF_DIMENSION_HORZ : AF_DIMENSION_VERT;
648
649 axis = &hints->axis[dim];
650
651 if ( idx >= axis->num_segments )
652 return FT_THROW( Invalid_Argument );
653
654 seg = &axis->segments[idx];
655 *offset = ( dim == AF_DIMENSION_HORZ ) ? seg->first->fx
656 : seg->first->fy;
657 if ( seg->edge )
658 *is_blue = FT_BOOL( seg->edge->blue_edge );
659 else
660 *is_blue = FALSE;
661
662 if ( *is_blue )
663 *blue_offset = seg->edge->blue_edge->org;
664 else
665 *blue_offset = 0;
666
667 return FT_Err_Ok;
668 }
669 #ifdef __cplusplus
670 }
671 #endif
672
673
674 /* Dump the array of linked edges. */
675
676 #ifdef __cplusplus
677 extern "C" {
678 #endif
679 void
680 af_glyph_hints_dump_edges( AF_GlyphHints hints,
681 FT_Bool to_stdout )
682 {
683 FT_Int dimension;
684
685
686 for ( dimension = 1; dimension >= 0; dimension-- )
687 {
688 AF_AxisHints axis = &hints->axis[dimension];
689 AF_Edge edges = axis->edges;
690 AF_Edge limit = edges + axis->num_edges;
691 AF_Edge edge;
692
693 char buf1[16], buf2[16];
694
695
696 /*
697 * note: AF_DIMENSION_HORZ corresponds to _vertical_ edges
698 * since they have a constant X coordinate.
699 */
700 if ( dimension == AF_DIMENSION_HORZ )
701 AF_DUMP(( "Table of %s edges (1px=%.2fu, 10u=%.2fpx):\n",
702 "vertical",
703 65536 * 64 / (double)hints->x_scale,
704 10 * (double)hints->x_scale / 65536 / 64 ));
705 else
706 AF_DUMP(( "Table of %s edges (1px=%.2fu, 10u=%.2fpx):\n",
707 "horizontal",
708 65536 * 64 / (double)hints->y_scale,
709 10 * (double)hints->y_scale / 65536 / 64 ));
710
711 if ( axis->num_edges )
712 {
713 AF_DUMP(( " index pos dir link serif"
714 /* " XXXXX XXXX.XX XXXXX XXXX XXXXX" */
715 " blue opos pos flags\n" ));
716 /* " X XXXX.XX XXXX.XX XXXXXXXXXXX" */
717 }
718 else
719 AF_DUMP(( " (none)\n" ));
720
721 for ( edge = edges; edge < limit; edge++ )
722 AF_DUMP(( " %5d %7.2f %5s %4s %5s"
723 " %c %7.2f %7.2f %11s\n",
724 AF_INDEX_NUM( edge, edges ),
725 (double)(int)edge->opos / 64,
726 af_dir_str( (AF_Direction)edge->dir ),
727 af_print_idx( buf1, 16,
728 AF_INDEX_NUM( edge->link, edges ) ),
729 af_print_idx( buf2, 16,
730 AF_INDEX_NUM( edge->serif, edges ) ),
731
732 edge->blue_edge ? 'y' : 'n',
733 (double)edge->opos / 64,
734 (double)edge->pos / 64,
735 af_edge_flags_to_string( edge->flags ) ));
736 AF_DUMP(( "\n" ));
737 }
738 }
739 #ifdef __cplusplus
740 }
741 #endif
742
743 #undef AF_DUMP
744
745 #endif /* !FT_DEBUG_AUTOFIT */
746
747
748 /* Compute the direction value of a given vector. */
749
750 FT_LOCAL_DEF( AF_Direction )
751 af_direction_compute( FT_Pos dx,
752 FT_Pos dy )
753 {
754 FT_Pos ll, ss; /* long and short arm lengths */
755 AF_Direction dir; /* candidate direction */
756
757
758 if ( dy >= dx )
759 {
760 if ( dy >= -dx )
761 {
762 dir = AF_DIR_UP;
763 ll = dy;
764 ss = dx;
765 }
766 else
767 {
768 dir = AF_DIR_LEFT;
769 ll = -dx;
770 ss = dy;
771 }
772 }
773 else /* dy < dx */
774 {
775 if ( dy >= -dx )
776 {
777 dir = AF_DIR_RIGHT;
778 ll = dx;
779 ss = dy;
780 }
781 else
782 {
783 dir = AF_DIR_DOWN;
784 ll = -dy;
785 ss = dx;
786 }
787 }
788
789 /* return no direction if arm lengths do not differ enough */
790 /* (value 14 is heuristic, corresponding to approx. 4.1 degrees) */
791 /* the long arm is never negative */
792 if ( ll <= 14 * FT_ABS( ss ) )
793 dir = AF_DIR_NONE;
794
795 return dir;
796 }
797
798
799 FT_LOCAL_DEF( void )
800 af_glyph_hints_init( AF_GlyphHints hints,
801 FT_Memory memory )
802 {
803 /* no need to initialize the embedded items */
804 FT_MEM_ZERO( hints, sizeof ( *hints ) - sizeof ( hints->embedded ) );
805 hints->memory = memory;
806 }
807
808
809 FT_LOCAL_DEF( void )
810 af_glyph_hints_done( AF_GlyphHints hints )
811 {
812 FT_Memory memory;
813 int dim;
814
815
816 if ( !( hints && hints->memory ) )
817 return;
818
819 memory = hints->memory;
820
821 /*
822 * note that we don't need to free the segment and edge
823 * buffers since they are really within the hints->points array
824 */
825 for ( dim = 0; dim < AF_DIMENSION_MAX; dim++ )
826 {
827 AF_AxisHints axis = &hints->axis[dim];
828
829
830 axis->num_segments = 0;
831 axis->max_segments = 0;
832 if ( axis->segments != axis->embedded.segments )
833 FT_FREE( axis->segments );
834
835 axis->num_edges = 0;
836 axis->max_edges = 0;
837 if ( axis->edges != axis->embedded.edges )
838 FT_FREE( axis->edges );
839 }
840
841 if ( hints->contours != hints->embedded.contours )
842 FT_FREE( hints->contours );
843 hints->max_contours = 0;
844 hints->num_contours = 0;
845
846 if ( hints->points != hints->embedded.points )
847 FT_FREE( hints->points );
848 hints->max_points = 0;
849 hints->num_points = 0;
850
851 hints->memory = NULL;
852 }
853
854
855 /* Reset metrics. */
856
857 FT_LOCAL_DEF( void )
858 af_glyph_hints_rescale( AF_GlyphHints hints,
859 AF_StyleMetrics metrics )
860 {
861 hints->metrics = metrics;
862 hints->scaler_flags = metrics->scaler.flags;
863 }
864
865
866 /* Recompute all AF_Point in AF_GlyphHints from the definitions */
867 /* in a source outline. */
868
869 FT_LOCAL_DEF( FT_Error )
870 af_glyph_hints_reload( AF_GlyphHints hints,
871 FT_Outline* outline )
872 {
873 FT_Error error = FT_Err_Ok;
874 AF_Point points;
875 FT_Int old_max, new_max;
876 FT_Fixed x_scale = hints->x_scale;
877 FT_Fixed y_scale = hints->y_scale;
878 FT_Pos x_delta = hints->x_delta;
879 FT_Pos y_delta = hints->y_delta;
880 FT_Memory memory = hints->memory;
881
882
883 hints->num_points = 0;
884 hints->num_contours = 0;
885
886 hints->axis[0].num_segments = 0;
887 hints->axis[0].num_edges = 0;
888 hints->axis[1].num_segments = 0;
889 hints->axis[1].num_edges = 0;
890
891 /* first of all, reallocate the contours array if necessary */
892 new_max = outline->n_contours;
893 old_max = hints->max_contours;
894
895 if ( new_max <= AF_CONTOURS_EMBEDDED )
896 {
897 if ( !hints->contours )
898 {
899 hints->contours = hints->embedded.contours;
900 hints->max_contours = AF_CONTOURS_EMBEDDED;
901 }
902 }
903 else if ( new_max > old_max )
904 {
905 if ( hints->contours == hints->embedded.contours )
906 hints->contours = NULL;
907
908 new_max = ( new_max + 3 ) & ~3; /* round up to a multiple of 4 */
909
910 if ( FT_RENEW_ARRAY( hints->contours, old_max, new_max ) )
911 goto Exit;
912
913 hints->max_contours = new_max;
914 }
915
916 /*
917 * then reallocate the points arrays if necessary --
918 * note that we reserve two additional point positions, used to
919 * hint metrics appropriately
920 */
921 new_max = outline->n_points + 2;
922 old_max = hints->max_points;
923
924 if ( new_max <= AF_POINTS_EMBEDDED )
925 {
926 if ( !hints->points )
927 {
928 hints->points = hints->embedded.points;
929 hints->max_points = AF_POINTS_EMBEDDED;
930 }
931 }
932 else if ( new_max > old_max )
933 {
934 if ( hints->points == hints->embedded.points )
935 hints->points = NULL;
936
937 new_max = ( new_max + 2 + 7 ) & ~7; /* round up to a multiple of 8 */
938
939 if ( FT_RENEW_ARRAY( hints->points, old_max, new_max ) )
940 goto Exit;
941
942 hints->max_points = new_max;
943 }
944
945 hints->num_points = outline->n_points;
946 hints->num_contours = outline->n_contours;
947
948 /* We can't rely on the value of `FT_Outline.flags' to know the fill */
949 /* direction used for a glyph, given that some fonts are broken (e.g., */
950 /* the Arphic ones). We thus recompute it each time we need to. */
951 /* */
952 hints->axis[AF_DIMENSION_HORZ].major_dir = AF_DIR_UP;
953 hints->axis[AF_DIMENSION_VERT].major_dir = AF_DIR_LEFT;
954
955 if ( FT_Outline_Get_Orientation( outline ) == FT_ORIENTATION_POSTSCRIPT )
956 {
957 hints->axis[AF_DIMENSION_HORZ].major_dir = AF_DIR_DOWN;
958 hints->axis[AF_DIMENSION_VERT].major_dir = AF_DIR_RIGHT;
959 }
960
961 hints->x_scale = x_scale;
962 hints->y_scale = y_scale;
963 hints->x_delta = x_delta;
964 hints->y_delta = y_delta;
965
966 points = hints->points;
967 if ( hints->num_points == 0 )
968 goto Exit;
969
970 {
971 AF_Point point;
972 AF_Point point_limit = points + hints->num_points;
973
974 /* value 20 in `near_limit' is heuristic */
975 FT_UInt units_per_em = hints->metrics->scaler.face->units_per_EM;
976 FT_Int near_limit = 20 * units_per_em / 2048;
977
978
979 /* compute coordinates & Bezier flags, next and prev */
980 {
981 FT_Vector* vec = outline->points;
982 char* tag = outline->tags;
983 FT_Short endpoint = outline->contours[0];
984 AF_Point end = points + endpoint;
985 AF_Point prev = end;
986 FT_Int contour_index = 0;
987
988
989 for ( point = points; point < point_limit; point++, vec++, tag++ )
990 {
991 FT_Pos out_x, out_y;
992
993
994 point->in_dir = (FT_Char)AF_DIR_NONE;
995 point->out_dir = (FT_Char)AF_DIR_NONE;
996
997 point->fx = (FT_Short)vec->x;
998 point->fy = (FT_Short)vec->y;
999 point->ox = point->x = FT_MulFix( vec->x, x_scale ) + x_delta;
1000 point->oy = point->y = FT_MulFix( vec->y, y_scale ) + y_delta;
1001
1002 end->fx = (FT_Short)outline->points[endpoint].x;
1003 end->fy = (FT_Short)outline->points[endpoint].y;
1004
1005 switch ( FT_CURVE_TAG( *tag ) )
1006 {
1007 case FT_CURVE_TAG_CONIC:
1008 point->flags = AF_FLAG_CONIC;
1009 break;
1010 case FT_CURVE_TAG_CUBIC:
1011 point->flags = AF_FLAG_CUBIC;
1012 break;
1013 default:
1014 point->flags = AF_FLAG_NONE;
1015 }
1016
1017 out_x = point->fx - prev->fx;
1018 out_y = point->fy - prev->fy;
1019
1020 if ( FT_ABS( out_x ) + FT_ABS( out_y ) < near_limit )
1021 prev->flags |= AF_FLAG_NEAR;
1022
1023 point->prev = prev;
1024 prev->next = point;
1025 prev = point;
1026
1027 if ( point == end )
1028 {
1029 if ( ++contour_index < outline->n_contours )
1030 {
1031 endpoint = outline->contours[contour_index];
1032 end = points + endpoint;
1033 prev = end;
1034 }
1035 }
1036
1037 #ifdef FT_DEBUG_AUTOFIT
1038 point->before[0] = NULL;
1039 point->before[1] = NULL;
1040 point->after[0] = NULL;
1041 point->after[1] = NULL;
1042 #endif
1043
1044 }
1045 }
1046
1047 /* set up the contours array */
1048 {
1049 AF_Point* contour = hints->contours;
1050 AF_Point* contour_limit = contour + hints->num_contours;
1051 short* end = outline->contours;
1052 short idx = 0;
1053
1054
1055 for ( ; contour < contour_limit; contour++, end++ )
1056 {
1057 contour[0] = points + idx;
1058 idx = (short)( end[0] + 1 );
1059 }
1060 }
1061
1062 {
1063 /*
1064 * Compute directions of `in' and `out' vectors.
1065 *
1066 * Note that distances between points that are very near to each
1067 * other are accumulated. In other words, the auto-hinter either
1068 * prepends the small vectors between near points to the first
1069 * non-near vector, or the sum of small vector lengths exceeds a
1070 * threshold, thus `grouping' the small vectors. All intermediate
1071 * points are tagged as weak; the directions are adjusted also to
1072 * be equal to the accumulated one.
1073 */
1074
1075 FT_Int near_limit2 = 2 * near_limit - 1;
1076
1077 AF_Point* contour;
1078 AF_Point* contour_limit = hints->contours + hints->num_contours;
1079
1080
1081 for ( contour = hints->contours; contour < contour_limit; contour++ )
1082 {
1083 AF_Point first = *contour;
1084 AF_Point next, prev, curr;
1085
1086 FT_Pos out_x, out_y;
1087
1088
1089 /* since the first point of a contour could be part of a */
1090 /* series of near points, go backwards to find the first */
1091 /* non-near point and adjust `first' */
1092
1093 point = first;
1094 prev = first->prev;
1095
1096 while ( prev != first )
1097 {
1098 out_x = point->fx - prev->fx;
1099 out_y = point->fy - prev->fy;
1100
1101 /*
1102 * We use Taxicab metrics to measure the vector length.
1103 *
1104 * Note that the accumulated distances so far could have the
1105 * opposite direction of the distance measured here. For this
1106 * reason we use `near_limit2' for the comparison to get a
1107 * non-near point even in the worst case.
1108 */
1109 if ( FT_ABS( out_x ) + FT_ABS( out_y ) >= near_limit2 )
1110 break;
1111
1112 point = prev;
1113 prev = prev->prev;
1114 }
1115
1116 /* adjust first point */
1117 first = point;
1118
1119 /* now loop over all points of the contour to get */
1120 /* `in' and `out' vector directions */
1121
1122 curr = first;
1123
1124 /*
1125 * We abuse the `u' and `v' fields to store index deltas to the
1126 * next and previous non-near point, respectively.
1127 *
1128 * To avoid problems with not having non-near points, we point to
1129 * `first' by default as the next non-near point.
1130 *
1131 */
1132 curr->u = (FT_Pos)( first - curr );
1133 first->v = -curr->u;
1134
1135 out_x = 0;
1136 out_y = 0;
1137
1138 next = first;
1139 do
1140 {
1141 AF_Direction out_dir;
1142
1143
1144 point = next;
1145 next = point->next;
1146
1147 out_x += next->fx - point->fx;
1148 out_y += next->fy - point->fy;
1149
1150 if ( FT_ABS( out_x ) + FT_ABS( out_y ) < near_limit )
1151 {
1152 next->flags |= AF_FLAG_WEAK_INTERPOLATION;
1153 continue;
1154 }
1155
1156 curr->u = (FT_Pos)( next - curr );
1157 next->v = -curr->u;
1158
1159 out_dir = af_direction_compute( out_x, out_y );
1160
1161 /* adjust directions for all points inbetween; */
1162 /* the loop also updates position of `curr' */
1163 curr->out_dir = (FT_Char)out_dir;
1164 for ( curr = curr->next; curr != next; curr = curr->next )
1165 {
1166 curr->in_dir = (FT_Char)out_dir;
1167 curr->out_dir = (FT_Char)out_dir;
1168 }
1169 next->in_dir = (FT_Char)out_dir;
1170
1171 curr->u = (FT_Pos)( first - curr );
1172 first->v = -curr->u;
1173
1174 out_x = 0;
1175 out_y = 0;
1176
1177 } while ( next != first );
1178 }
1179
1180 /*
1181 * The next step is to `simplify' an outline's topology so that we
1182 * can identify local extrema more reliably: A series of
1183 * non-horizontal or non-vertical vectors pointing into the same
1184 * quadrant are handled as a single, long vector. From a
1185 * topological point of the view, the intermediate points are of no
1186 * interest and thus tagged as weak.
1187 */
1188
1189 for ( point = points; point < point_limit; point++ )
1190 {
1191 if ( point->flags & AF_FLAG_WEAK_INTERPOLATION )
1192 continue;
1193
1194 if ( point->in_dir == AF_DIR_NONE &&
1195 point->out_dir == AF_DIR_NONE )
1196 {
1197 /* check whether both vectors point into the same quadrant */
1198
1199 FT_Pos in_x, in_y;
1200 FT_Pos out_x, out_y;
1201
1202 AF_Point next_u = point + point->u;
1203 AF_Point prev_v = point + point->v;
1204
1205
1206 in_x = point->fx - prev_v->fx;
1207 in_y = point->fy - prev_v->fy;
1208
1209 out_x = next_u->fx - point->fx;
1210 out_y = next_u->fy - point->fy;
1211
1212 if ( ( in_x ^ out_x ) >= 0 && ( in_y ^ out_y ) >= 0 )
1213 {
1214 /* yes, so tag current point as weak */
1215 /* and update index deltas */
1216
1217 point->flags |= AF_FLAG_WEAK_INTERPOLATION;
1218
1219 prev_v->u = (FT_Pos)( next_u - prev_v );
1220 next_u->v = -prev_v->u;
1221 }
1222 }
1223 }
1224
1225 /*
1226 * Finally, check for remaining weak points. Everything else not
1227 * collected in edges so far is then implicitly classified as strong
1228 * points.
1229 */
1230
1231 for ( point = points; point < point_limit; point++ )
1232 {
1233 if ( point->flags & AF_FLAG_WEAK_INTERPOLATION )
1234 continue;
1235
1236 if ( point->flags & AF_FLAG_CONTROL )
1237 {
1238 /* control points are always weak */
1239 Is_Weak_Point:
1240 point->flags |= AF_FLAG_WEAK_INTERPOLATION;
1241 }
1242 else if ( point->out_dir == point->in_dir )
1243 {
1244 if ( point->out_dir != AF_DIR_NONE )
1245 {
1246 /* current point lies on a horizontal or */
1247 /* vertical segment (but doesn't start or end it) */
1248 goto Is_Weak_Point;
1249 }
1250
1251 {
1252 AF_Point next_u = point + point->u;
1253 AF_Point prev_v = point + point->v;
1254
1255
1256 if ( ft_corner_is_flat( point->fx - prev_v->fx,
1257 point->fy - prev_v->fy,
1258 next_u->fx - point->fx,
1259 next_u->fy - point->fy ) )
1260 {
1261 /* either the `in' or the `out' vector is much more */
1262 /* dominant than the other one, so tag current point */
1263 /* as weak and update index deltas */
1264
1265 prev_v->u = (FT_Pos)( next_u - prev_v );
1266 next_u->v = -prev_v->u;
1267
1268 goto Is_Weak_Point;
1269 }
1270 }
1271 }
1272 else if ( point->in_dir == -point->out_dir )
1273 {
1274 /* current point forms a spike */
1275 goto Is_Weak_Point;
1276 }
1277 }
1278 }
1279 }
1280
1281 Exit:
1282 return error;
1283 }
1284
1285
1286 /* Store the hinted outline in an FT_Outline structure. */
1287
1288 FT_LOCAL_DEF( void )
1289 af_glyph_hints_save( AF_GlyphHints hints,
1290 FT_Outline* outline )
1291 {
1292 AF_Point point = hints->points;
1293 AF_Point limit = point + hints->num_points;
1294 FT_Vector* vec = outline->points;
1295 char* tag = outline->tags;
1296
1297
1298 for ( ; point < limit; point++, vec++, tag++ )
1299 {
1300 vec->x = point->x;
1301 vec->y = point->y;
1302
1303 if ( point->flags & AF_FLAG_CONIC )
1304 tag[0] = FT_CURVE_TAG_CONIC;
1305 else if ( point->flags & AF_FLAG_CUBIC )
1306 tag[0] = FT_CURVE_TAG_CUBIC;
1307 else
1308 tag[0] = FT_CURVE_TAG_ON;
1309 }
1310 }
1311
1312
1313 /****************************************************************
1314 *
1315 * EDGE POINT GRID-FITTING
1316 *
1317 ****************************************************************/
1318
1319
1320 /* Align all points of an edge to the same coordinate value, */
1321 /* either horizontally or vertically. */
1322
1323 FT_LOCAL_DEF( void )
1324 af_glyph_hints_align_edge_points( AF_GlyphHints hints,
1325 AF_Dimension dim )
1326 {
1327 AF_AxisHints axis = & hints->axis[dim];
1328 AF_Segment segments = axis->segments;
1329 AF_Segment segment_limit = FT_OFFSET( segments, axis->num_segments );
1330 AF_Segment seg;
1331
1332
1333 if ( dim == AF_DIMENSION_HORZ )
1334 {
1335 for ( seg = segments; seg < segment_limit; seg++ )
1336 {
1337 AF_Edge edge = seg->edge;
1338 AF_Point point, first, last;
1339
1340
1341 if ( !edge )
1342 continue;
1343
1344 first = seg->first;
1345 last = seg->last;
1346 point = first;
1347 for (;;)
1348 {
1349 point->x = edge->pos;
1350 point->flags |= AF_FLAG_TOUCH_X;
1351
1352 if ( point == last )
1353 break;
1354
1355 point = point->next;
1356 }
1357 }
1358 }
1359 else
1360 {
1361 for ( seg = segments; seg < segment_limit; seg++ )
1362 {
1363 AF_Edge edge = seg->edge;
1364 AF_Point point, first, last;
1365
1366
1367 if ( !edge )
1368 continue;
1369
1370 first = seg->first;
1371 last = seg->last;
1372 point = first;
1373 for (;;)
1374 {
1375 point->y = edge->pos;
1376 point->flags |= AF_FLAG_TOUCH_Y;
1377
1378 if ( point == last )
1379 break;
1380
1381 point = point->next;
1382 }
1383 }
1384 }
1385 }
1386
1387
1388 /****************************************************************
1389 *
1390 * STRONG POINT INTERPOLATION
1391 *
1392 ****************************************************************/
1393
1394
1395 /* Hint the strong points -- this is equivalent to the TrueType `IP' */
1396 /* hinting instruction. */
1397
1398 FT_LOCAL_DEF( void )
1399 af_glyph_hints_align_strong_points( AF_GlyphHints hints,
1400 AF_Dimension dim )
1401 {
1402 AF_Point points = hints->points;
1403 AF_Point point_limit = points + hints->num_points;
1404 AF_AxisHints axis = &hints->axis[dim];
1405 AF_Edge edges = axis->edges;
1406 AF_Edge edge_limit = FT_OFFSET( edges, axis->num_edges );
1407 FT_UInt touch_flag;
1408
1409
1410 if ( dim == AF_DIMENSION_HORZ )
1411 touch_flag = AF_FLAG_TOUCH_X;
1412 else
1413 touch_flag = AF_FLAG_TOUCH_Y;
1414
1415 if ( edges < edge_limit )
1416 {
1417 AF_Point point;
1418 AF_Edge edge;
1419
1420
1421 for ( point = points; point < point_limit; point++ )
1422 {
1423 FT_Pos u, ou, fu; /* point position */
1424 FT_Pos delta;
1425
1426
1427 if ( point->flags & touch_flag )
1428 continue;
1429
1430 /* if this point is candidate to weak interpolation, we */
1431 /* interpolate it after all strong points have been processed */
1432
1433 if ( ( point->flags & AF_FLAG_WEAK_INTERPOLATION ) )
1434 continue;
1435
1436 if ( dim == AF_DIMENSION_VERT )
1437 {
1438 u = point->fy;
1439 ou = point->oy;
1440 }
1441 else
1442 {
1443 u = point->fx;
1444 ou = point->ox;
1445 }
1446
1447 fu = u;
1448
1449 /* is the point before the first edge? */
1450 edge = edges;
1451 delta = edge->fpos - u;
1452 if ( delta >= 0 )
1453 {
1454 u = edge->pos - ( edge->opos - ou );
1455
1456 #ifdef FT_DEBUG_AUTOFIT
1457 point->before[dim] = edge;
1458 point->after[dim] = NULL;
1459 #endif
1460
1461 goto Store_Point;
1462 }
1463
1464 /* is the point after the last edge? */
1465 edge = edge_limit - 1;
1466 delta = u - edge->fpos;
1467 if ( delta >= 0 )
1468 {
1469 u = edge->pos + ( ou - edge->opos );
1470
1471 #ifdef FT_DEBUG_AUTOFIT
1472 point->before[dim] = NULL;
1473 point->after[dim] = edge;
1474 #endif
1475
1476 goto Store_Point;
1477 }
1478
1479 {
1480 FT_PtrDist min, max, mid;
1481 FT_Pos fpos;
1482
1483
1484 /* find enclosing edges */
1485 min = 0;
1486 max = edge_limit - edges;
1487
1488 #if 1
1489 /* for a small number of edges, a linear search is better */
1490 if ( max <= 8 )
1491 {
1492 FT_PtrDist nn;
1493
1494
1495 for ( nn = 0; nn < max; nn++ )
1496 if ( edges[nn].fpos >= u )
1497 break;
1498
1499 if ( edges[nn].fpos == u )
1500 {
1501 u = edges[nn].pos;
1502 goto Store_Point;
1503 }
1504 min = nn;
1505 }
1506 else
1507 #endif
1508 while ( min < max )
1509 {
1510 mid = ( max + min ) >> 1;
1511 edge = edges + mid;
1512 fpos = edge->fpos;
1513
1514 if ( u < fpos )
1515 max = mid;
1516 else if ( u > fpos )
1517 min = mid + 1;
1518 else
1519 {
1520 /* we are on the edge */
1521 u = edge->pos;
1522
1523 #ifdef FT_DEBUG_AUTOFIT
1524 point->before[dim] = NULL;
1525 point->after[dim] = NULL;
1526 #endif
1527
1528 goto Store_Point;
1529 }
1530 }
1531
1532 /* point is not on an edge */
1533 {
1534 AF_Edge before = edges + min - 1;
1535 AF_Edge after = edges + min + 0;
1536
1537
1538 #ifdef FT_DEBUG_AUTOFIT
1539 point->before[dim] = before;
1540 point->after[dim] = after;
1541 #endif
1542
1543 /* assert( before && after && before != after ) */
1544 if ( before->scale == 0 )
1545 before->scale = FT_DivFix( after->pos - before->pos,
1546 after->fpos - before->fpos );
1547
1548 u = before->pos + FT_MulFix( fu - before->fpos,
1549 before->scale );
1550 }
1551 }
1552
1553 Store_Point:
1554 /* save the point position */
1555 if ( dim == AF_DIMENSION_HORZ )
1556 point->x = u;
1557 else
1558 point->y = u;
1559
1560 point->flags |= touch_flag;
1561 }
1562 }
1563 }
1564
1565
1566 /****************************************************************
1567 *
1568 * WEAK POINT INTERPOLATION
1569 *
1570 ****************************************************************/
1571
1572
1573 /* Shift the original coordinates of all points between `p1' and */
1574 /* `p2' to get hinted coordinates, using the same difference as */
1575 /* given by `ref'. */
1576
1577 static void
1578 af_iup_shift( AF_Point p1,
1579 AF_Point p2,
1580 AF_Point ref )
1581 {
1582 AF_Point p;
1583 FT_Pos delta = ref->u - ref->v;
1584
1585
1586 if ( delta == 0 )
1587 return;
1588
1589 for ( p = p1; p < ref; p++ )
1590 p->u = p->v + delta;
1591
1592 for ( p = ref + 1; p <= p2; p++ )
1593 p->u = p->v + delta;
1594 }
1595
1596
1597 /* Interpolate the original coordinates of all points between `p1' and */
1598 /* `p2' to get hinted coordinates, using `ref1' and `ref2' as the */
1599 /* reference points. The `u' and `v' members are the current and */
1600 /* original coordinate values, respectively. */
1601 /* */
1602 /* Details can be found in the TrueType bytecode specification. */
1603
1604 static void
1605 af_iup_interp( AF_Point p1,
1606 AF_Point p2,
1607 AF_Point ref1,
1608 AF_Point ref2 )
1609 {
1610 AF_Point p;
1611 FT_Pos u, v1, v2, u1, u2, d1, d2;
1612
1613
1614 if ( p1 > p2 )
1615 return;
1616
1617 if ( ref1->v > ref2->v )
1618 {
1619 p = ref1;
1620 ref1 = ref2;
1621 ref2 = p;
1622 }
1623
1624 v1 = ref1->v;
1625 v2 = ref2->v;
1626 u1 = ref1->u;
1627 u2 = ref2->u;
1628 d1 = u1 - v1;
1629 d2 = u2 - v2;
1630
1631 if ( u1 == u2 || v1 == v2 )
1632 {
1633 for ( p = p1; p <= p2; p++ )
1634 {
1635 u = p->v;
1636
1637 if ( u <= v1 )
1638 u += d1;
1639 else if ( u >= v2 )
1640 u += d2;
1641 else
1642 u = u1;
1643
1644 p->u = u;
1645 }
1646 }
1647 else
1648 {
1649 FT_Fixed scale = FT_DivFix( u2 - u1, v2 - v1 );
1650
1651
1652 for ( p = p1; p <= p2; p++ )
1653 {
1654 u = p->v;
1655
1656 if ( u <= v1 )
1657 u += d1;
1658 else if ( u >= v2 )
1659 u += d2;
1660 else
1661 u = u1 + FT_MulFix( u - v1, scale );
1662
1663 p->u = u;
1664 }
1665 }
1666 }
1667
1668
1669 /* Hint the weak points -- this is equivalent to the TrueType `IUP' */
1670 /* hinting instruction. */
1671
1672 FT_LOCAL_DEF( void )
1673 af_glyph_hints_align_weak_points( AF_GlyphHints hints,
1674 AF_Dimension dim )
1675 {
1676 AF_Point points = hints->points;
1677 AF_Point point_limit = points + hints->num_points;
1678 AF_Point* contour = hints->contours;
1679 AF_Point* contour_limit = contour + hints->num_contours;
1680 FT_UInt touch_flag;
1681 AF_Point point;
1682 AF_Point end_point;
1683 AF_Point first_point;
1684
1685
1686 /* PASS 1: Move segment points to edge positions */
1687
1688 if ( dim == AF_DIMENSION_HORZ )
1689 {
1690 touch_flag = AF_FLAG_TOUCH_X;
1691
1692 for ( point = points; point < point_limit; point++ )
1693 {
1694 point->u = point->x;
1695 point->v = point->ox;
1696 }
1697 }
1698 else
1699 {
1700 touch_flag = AF_FLAG_TOUCH_Y;
1701
1702 for ( point = points; point < point_limit; point++ )
1703 {
1704 point->u = point->y;
1705 point->v = point->oy;
1706 }
1707 }
1708
1709 for ( ; contour < contour_limit; contour++ )
1710 {
1711 AF_Point first_touched, last_touched;
1712
1713
1714 point = *contour;
1715 end_point = point->prev;
1716 first_point = point;
1717
1718 /* find first touched point */
1719 for (;;)
1720 {
1721 if ( point > end_point ) /* no touched point in contour */
1722 goto NextContour;
1723
1724 if ( point->flags & touch_flag )
1725 break;
1726
1727 point++;
1728 }
1729
1730 first_touched = point;
1731
1732 for (;;)
1733 {
1734 FT_ASSERT( point <= end_point &&
1735 ( point->flags & touch_flag ) != 0 );
1736
1737 /* skip any touched neighbours */
1738 while ( point < end_point &&
1739 ( point[1].flags & touch_flag ) != 0 )
1740 point++;
1741
1742 last_touched = point;
1743
1744 /* find the next touched point, if any */
1745 point++;
1746 for (;;)
1747 {
1748 if ( point > end_point )
1749 goto EndContour;
1750
1751 if ( ( point->flags & touch_flag ) != 0 )
1752 break;
1753
1754 point++;
1755 }
1756
1757 /* interpolate between last_touched and point */
1758 af_iup_interp( last_touched + 1, point - 1,
1759 last_touched, point );
1760 }
1761
1762 EndContour:
1763 /* special case: only one point was touched */
1764 if ( last_touched == first_touched )
1765 af_iup_shift( first_point, end_point, first_touched );
1766
1767 else /* interpolate the last part */
1768 {
1769 if ( last_touched < end_point )
1770 af_iup_interp( last_touched + 1, end_point,
1771 last_touched, first_touched );
1772
1773 if ( first_touched > points )
1774 af_iup_interp( first_point, first_touched - 1,
1775 last_touched, first_touched );
1776 }
1777
1778 NextContour:
1779 ;
1780 }
1781
1782 /* now save the interpolated values back to x/y */
1783 if ( dim == AF_DIMENSION_HORZ )
1784 {
1785 for ( point = points; point < point_limit; point++ )
1786 point->x = point->u;
1787 }
1788 else
1789 {
1790 for ( point = points; point < point_limit; point++ )
1791 point->y = point->u;
1792 }
1793 }
1794
1795
1796 /* END */