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[reactos.git] / lib / 3rdparty / freetype / src / pshinter / pshalgo.c
1 /***************************************************************************/
2 /* */
3 /* pshalgo.c */
4 /* */
5 /* PostScript hinting algorithm (body). */
6 /* */
7 /* Copyright 2001-2010, 2012-2014 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 <ft2build.h>
20 #include FT_INTERNAL_OBJECTS_H
21 #include FT_INTERNAL_DEBUG_H
22 #include FT_INTERNAL_CALC_H
23 #include "pshalgo.h"
24
25 #include "pshnterr.h"
26
27
28 #undef FT_COMPONENT
29 #define FT_COMPONENT trace_pshalgo2
30
31
32 #ifdef DEBUG_HINTER
33 PSH_Hint_Table ps_debug_hint_table = 0;
34 PSH_HintFunc ps_debug_hint_func = 0;
35 PSH_Glyph ps_debug_glyph = 0;
36 #endif
37
38
39 #define COMPUTE_INFLEXS /* compute inflection points to optimize `S' */
40 /* and similar glyphs */
41 #define STRONGER /* slightly increase the contrast of smooth */
42 /* hinting */
43
44
45 /*************************************************************************/
46 /*************************************************************************/
47 /***** *****/
48 /***** BASIC HINTS RECORDINGS *****/
49 /***** *****/
50 /*************************************************************************/
51 /*************************************************************************/
52
53 /* return true if two stem hints overlap */
54 static FT_Int
55 psh_hint_overlap( PSH_Hint hint1,
56 PSH_Hint hint2 )
57 {
58 return hint1->org_pos + hint1->org_len >= hint2->org_pos &&
59 hint2->org_pos + hint2->org_len >= hint1->org_pos;
60 }
61
62
63 /* destroy hints table */
64 static void
65 psh_hint_table_done( PSH_Hint_Table table,
66 FT_Memory memory )
67 {
68 FT_FREE( table->zones );
69 table->num_zones = 0;
70 table->zone = 0;
71
72 FT_FREE( table->sort );
73 FT_FREE( table->hints );
74 table->num_hints = 0;
75 table->max_hints = 0;
76 table->sort_global = 0;
77 }
78
79
80 /* deactivate all hints in a table */
81 static void
82 psh_hint_table_deactivate( PSH_Hint_Table table )
83 {
84 FT_UInt count = table->max_hints;
85 PSH_Hint hint = table->hints;
86
87
88 for ( ; count > 0; count--, hint++ )
89 {
90 psh_hint_deactivate( hint );
91 hint->order = -1;
92 }
93 }
94
95
96 /* internal function to record a new hint */
97 static void
98 psh_hint_table_record( PSH_Hint_Table table,
99 FT_UInt idx )
100 {
101 PSH_Hint hint = table->hints + idx;
102
103
104 if ( idx >= table->max_hints )
105 {
106 FT_TRACE0(( "psh_hint_table_record: invalid hint index %d\n", idx ));
107 return;
108 }
109
110 /* ignore active hints */
111 if ( psh_hint_is_active( hint ) )
112 return;
113
114 psh_hint_activate( hint );
115
116 /* now scan the current active hint set to check */
117 /* whether `hint' overlaps with another hint */
118 {
119 PSH_Hint* sorted = table->sort_global;
120 FT_UInt count = table->num_hints;
121 PSH_Hint hint2;
122
123
124 hint->parent = 0;
125 for ( ; count > 0; count--, sorted++ )
126 {
127 hint2 = sorted[0];
128
129 if ( psh_hint_overlap( hint, hint2 ) )
130 {
131 hint->parent = hint2;
132 break;
133 }
134 }
135 }
136
137 if ( table->num_hints < table->max_hints )
138 table->sort_global[table->num_hints++] = hint;
139 else
140 FT_TRACE0(( "psh_hint_table_record: too many sorted hints! BUG!\n" ));
141 }
142
143
144 static void
145 psh_hint_table_record_mask( PSH_Hint_Table table,
146 PS_Mask hint_mask )
147 {
148 FT_Int mask = 0, val = 0;
149 FT_Byte* cursor = hint_mask->bytes;
150 FT_UInt idx, limit;
151
152
153 limit = hint_mask->num_bits;
154
155 for ( idx = 0; idx < limit; idx++ )
156 {
157 if ( mask == 0 )
158 {
159 val = *cursor++;
160 mask = 0x80;
161 }
162
163 if ( val & mask )
164 psh_hint_table_record( table, idx );
165
166 mask >>= 1;
167 }
168 }
169
170
171 /* create hints table */
172 static FT_Error
173 psh_hint_table_init( PSH_Hint_Table table,
174 PS_Hint_Table hints,
175 PS_Mask_Table hint_masks,
176 PS_Mask_Table counter_masks,
177 FT_Memory memory )
178 {
179 FT_UInt count;
180 FT_Error error;
181
182 FT_UNUSED( counter_masks );
183
184
185 count = hints->num_hints;
186
187 /* allocate our tables */
188 if ( FT_NEW_ARRAY( table->sort, 2 * count ) ||
189 FT_NEW_ARRAY( table->hints, count ) ||
190 FT_NEW_ARRAY( table->zones, 2 * count + 1 ) )
191 goto Exit;
192
193 table->max_hints = count;
194 table->sort_global = table->sort + count;
195 table->num_hints = 0;
196 table->num_zones = 0;
197 table->zone = 0;
198
199 /* initialize the `table->hints' array */
200 {
201 PSH_Hint write = table->hints;
202 PS_Hint read = hints->hints;
203
204
205 for ( ; count > 0; count--, write++, read++ )
206 {
207 write->org_pos = read->pos;
208 write->org_len = read->len;
209 write->flags = read->flags;
210 }
211 }
212
213 /* we now need to determine the initial `parent' stems; first */
214 /* activate the hints that are given by the initial hint masks */
215 if ( hint_masks )
216 {
217 PS_Mask mask = hint_masks->masks;
218
219
220 count = hint_masks->num_masks;
221 table->hint_masks = hint_masks;
222
223 for ( ; count > 0; count--, mask++ )
224 psh_hint_table_record_mask( table, mask );
225 }
226
227 /* finally, do a linear parse in case some hints were left alone */
228 if ( table->num_hints != table->max_hints )
229 {
230 FT_UInt idx;
231
232
233 FT_TRACE0(( "psh_hint_table_init: missing/incorrect hint masks\n" ));
234
235 count = table->max_hints;
236 for ( idx = 0; idx < count; idx++ )
237 psh_hint_table_record( table, idx );
238 }
239
240 Exit:
241 return error;
242 }
243
244
245 static void
246 psh_hint_table_activate_mask( PSH_Hint_Table table,
247 PS_Mask hint_mask )
248 {
249 FT_Int mask = 0, val = 0;
250 FT_Byte* cursor = hint_mask->bytes;
251 FT_UInt idx, limit, count;
252
253
254 limit = hint_mask->num_bits;
255 count = 0;
256
257 psh_hint_table_deactivate( table );
258
259 for ( idx = 0; idx < limit; idx++ )
260 {
261 if ( mask == 0 )
262 {
263 val = *cursor++;
264 mask = 0x80;
265 }
266
267 if ( val & mask )
268 {
269 PSH_Hint hint = &table->hints[idx];
270
271
272 if ( !psh_hint_is_active( hint ) )
273 {
274 FT_UInt count2;
275
276 #if 0
277 PSH_Hint* sort = table->sort;
278 PSH_Hint hint2;
279
280
281 for ( count2 = count; count2 > 0; count2--, sort++ )
282 {
283 hint2 = sort[0];
284 if ( psh_hint_overlap( hint, hint2 ) )
285 FT_TRACE0(( "psh_hint_table_activate_mask:"
286 " found overlapping hints\n" ))
287 }
288 #else
289 count2 = 0;
290 #endif
291
292 if ( count2 == 0 )
293 {
294 psh_hint_activate( hint );
295 if ( count < table->max_hints )
296 table->sort[count++] = hint;
297 else
298 FT_TRACE0(( "psh_hint_tableactivate_mask:"
299 " too many active hints\n" ));
300 }
301 }
302 }
303
304 mask >>= 1;
305 }
306 table->num_hints = count;
307
308 /* now, sort the hints; they are guaranteed to not overlap */
309 /* so we can compare their "org_pos" field directly */
310 {
311 FT_Int i1, i2;
312 PSH_Hint hint1, hint2;
313 PSH_Hint* sort = table->sort;
314
315
316 /* a simple bubble sort will do, since in 99% of cases, the hints */
317 /* will be already sorted -- and the sort will be linear */
318 for ( i1 = 1; i1 < (FT_Int)count; i1++ )
319 {
320 hint1 = sort[i1];
321 for ( i2 = i1 - 1; i2 >= 0; i2-- )
322 {
323 hint2 = sort[i2];
324
325 if ( hint2->org_pos < hint1->org_pos )
326 break;
327
328 sort[i2 + 1] = hint2;
329 sort[i2] = hint1;
330 }
331 }
332 }
333 }
334
335
336 /*************************************************************************/
337 /*************************************************************************/
338 /***** *****/
339 /***** HINTS GRID-FITTING AND OPTIMIZATION *****/
340 /***** *****/
341 /*************************************************************************/
342 /*************************************************************************/
343
344 #if 1
345 static FT_Pos
346 psh_dimension_quantize_len( PSH_Dimension dim,
347 FT_Pos len,
348 FT_Bool do_snapping )
349 {
350 if ( len <= 64 )
351 len = 64;
352 else
353 {
354 FT_Pos delta = len - dim->stdw.widths[0].cur;
355
356
357 if ( delta < 0 )
358 delta = -delta;
359
360 if ( delta < 40 )
361 {
362 len = dim->stdw.widths[0].cur;
363 if ( len < 48 )
364 len = 48;
365 }
366
367 if ( len < 3 * 64 )
368 {
369 delta = ( len & 63 );
370 len &= -64;
371
372 if ( delta < 10 )
373 len += delta;
374
375 else if ( delta < 32 )
376 len += 10;
377
378 else if ( delta < 54 )
379 len += 54;
380
381 else
382 len += delta;
383 }
384 else
385 len = FT_PIX_ROUND( len );
386 }
387
388 if ( do_snapping )
389 len = FT_PIX_ROUND( len );
390
391 return len;
392 }
393 #endif /* 0 */
394
395
396 #ifdef DEBUG_HINTER
397
398 static void
399 ps_simple_scale( PSH_Hint_Table table,
400 FT_Fixed scale,
401 FT_Fixed delta,
402 FT_Int dimension )
403 {
404 FT_UInt count;
405
406
407 for ( count = 0; count < table->max_hints; count++ )
408 {
409 PSH_Hint hint = table->hints + count;
410
411
412 hint->cur_pos = FT_MulFix( hint->org_pos, scale ) + delta;
413 hint->cur_len = FT_MulFix( hint->org_len, scale );
414
415 if ( ps_debug_hint_func )
416 ps_debug_hint_func( hint, dimension );
417 }
418 }
419
420 #endif /* DEBUG_HINTER */
421
422
423 static FT_Fixed
424 psh_hint_snap_stem_side_delta( FT_Fixed pos,
425 FT_Fixed len )
426 {
427 FT_Fixed delta1 = FT_PIX_ROUND( pos ) - pos;
428 FT_Fixed delta2 = FT_PIX_ROUND( pos + len ) - pos - len;
429
430
431 if ( FT_ABS( delta1 ) <= FT_ABS( delta2 ) )
432 return delta1;
433 else
434 return delta2;
435 }
436
437
438 static void
439 psh_hint_align( PSH_Hint hint,
440 PSH_Globals globals,
441 FT_Int dimension,
442 PSH_Glyph glyph )
443 {
444 PSH_Dimension dim = &globals->dimension[dimension];
445 FT_Fixed scale = dim->scale_mult;
446 FT_Fixed delta = dim->scale_delta;
447
448
449 if ( !psh_hint_is_fitted( hint ) )
450 {
451 FT_Pos pos = FT_MulFix( hint->org_pos, scale ) + delta;
452 FT_Pos len = FT_MulFix( hint->org_len, scale );
453
454 FT_Int do_snapping;
455 FT_Pos fit_len;
456 PSH_AlignmentRec align;
457
458
459 /* ignore stem alignments when requested through the hint flags */
460 if ( ( dimension == 0 && !glyph->do_horz_hints ) ||
461 ( dimension == 1 && !glyph->do_vert_hints ) )
462 {
463 hint->cur_pos = pos;
464 hint->cur_len = len;
465
466 psh_hint_set_fitted( hint );
467 return;
468 }
469
470 /* perform stem snapping when requested - this is necessary
471 * for monochrome and LCD hinting modes only
472 */
473 do_snapping = ( dimension == 0 && glyph->do_horz_snapping ) ||
474 ( dimension == 1 && glyph->do_vert_snapping );
475
476 hint->cur_len = fit_len = len;
477
478 /* check blue zones for horizontal stems */
479 align.align = PSH_BLUE_ALIGN_NONE;
480 align.align_bot = align.align_top = 0;
481
482 if ( dimension == 1 )
483 psh_blues_snap_stem( &globals->blues,
484 hint->org_pos + hint->org_len,
485 hint->org_pos,
486 &align );
487
488 switch ( align.align )
489 {
490 case PSH_BLUE_ALIGN_TOP:
491 /* the top of the stem is aligned against a blue zone */
492 hint->cur_pos = align.align_top - fit_len;
493 break;
494
495 case PSH_BLUE_ALIGN_BOT:
496 /* the bottom of the stem is aligned against a blue zone */
497 hint->cur_pos = align.align_bot;
498 break;
499
500 case PSH_BLUE_ALIGN_TOP | PSH_BLUE_ALIGN_BOT:
501 /* both edges of the stem are aligned against blue zones */
502 hint->cur_pos = align.align_bot;
503 hint->cur_len = align.align_top - align.align_bot;
504 break;
505
506 default:
507 {
508 PSH_Hint parent = hint->parent;
509
510
511 if ( parent )
512 {
513 FT_Pos par_org_center, par_cur_center;
514 FT_Pos cur_org_center, cur_delta;
515
516
517 /* ensure that parent is already fitted */
518 if ( !psh_hint_is_fitted( parent ) )
519 psh_hint_align( parent, globals, dimension, glyph );
520
521 /* keep original relation between hints, this is, use the */
522 /* scaled distance between the centers of the hints to */
523 /* compute the new position */
524 par_org_center = parent->org_pos + ( parent->org_len >> 1 );
525 par_cur_center = parent->cur_pos + ( parent->cur_len >> 1 );
526 cur_org_center = hint->org_pos + ( hint->org_len >> 1 );
527
528 cur_delta = FT_MulFix( cur_org_center - par_org_center, scale );
529 pos = par_cur_center + cur_delta - ( len >> 1 );
530 }
531
532 hint->cur_pos = pos;
533 hint->cur_len = fit_len;
534
535 /* Stem adjustment tries to snap stem widths to standard
536 * ones. This is important to prevent unpleasant rounding
537 * artefacts.
538 */
539 if ( glyph->do_stem_adjust )
540 {
541 if ( len <= 64 )
542 {
543 /* the stem is less than one pixel; we will center it
544 * around the nearest pixel center
545 */
546 if ( len >= 32 )
547 {
548 /* This is a special case where we also widen the stem
549 * and align it to the pixel grid.
550 *
551 * stem_center = pos + (len/2)
552 * nearest_pixel_center = FT_ROUND(stem_center-32)+32
553 * new_pos = nearest_pixel_center-32
554 * = FT_ROUND(stem_center-32)
555 * = FT_FLOOR(stem_center-32+32)
556 * = FT_FLOOR(stem_center)
557 * new_len = 64
558 */
559 pos = FT_PIX_FLOOR( pos + ( len >> 1 ) );
560 len = 64;
561 }
562 else if ( len > 0 )
563 {
564 /* This is a very small stem; we simply align it to the
565 * pixel grid, trying to find the minimum displacement.
566 *
567 * left = pos
568 * right = pos + len
569 * left_nearest_edge = ROUND(pos)
570 * right_nearest_edge = ROUND(right)
571 *
572 * if ( ABS(left_nearest_edge - left) <=
573 * ABS(right_nearest_edge - right) )
574 * new_pos = left
575 * else
576 * new_pos = right
577 */
578 FT_Pos left_nearest = FT_PIX_ROUND( pos );
579 FT_Pos right_nearest = FT_PIX_ROUND( pos + len );
580 FT_Pos left_disp = left_nearest - pos;
581 FT_Pos right_disp = right_nearest - ( pos + len );
582
583
584 if ( left_disp < 0 )
585 left_disp = -left_disp;
586 if ( right_disp < 0 )
587 right_disp = -right_disp;
588 if ( left_disp <= right_disp )
589 pos = left_nearest;
590 else
591 pos = right_nearest;
592 }
593 else
594 {
595 /* this is a ghost stem; we simply round it */
596 pos = FT_PIX_ROUND( pos );
597 }
598 }
599 else
600 {
601 len = psh_dimension_quantize_len( dim, len, 0 );
602 }
603 }
604
605 /* now that we have a good hinted stem width, try to position */
606 /* the stem along a pixel grid integer coordinate */
607 hint->cur_pos = pos + psh_hint_snap_stem_side_delta( pos, len );
608 hint->cur_len = len;
609 }
610 }
611
612 if ( do_snapping )
613 {
614 pos = hint->cur_pos;
615 len = hint->cur_len;
616
617 if ( len < 64 )
618 len = 64;
619 else
620 len = FT_PIX_ROUND( len );
621
622 switch ( align.align )
623 {
624 case PSH_BLUE_ALIGN_TOP:
625 hint->cur_pos = align.align_top - len;
626 hint->cur_len = len;
627 break;
628
629 case PSH_BLUE_ALIGN_BOT:
630 hint->cur_len = len;
631 break;
632
633 case PSH_BLUE_ALIGN_BOT | PSH_BLUE_ALIGN_TOP:
634 /* don't touch */
635 break;
636
637
638 default:
639 hint->cur_len = len;
640 if ( len & 64 )
641 pos = FT_PIX_FLOOR( pos + ( len >> 1 ) ) + 32;
642 else
643 pos = FT_PIX_ROUND( pos + ( len >> 1 ) );
644
645 hint->cur_pos = pos - ( len >> 1 );
646 hint->cur_len = len;
647 }
648 }
649
650 psh_hint_set_fitted( hint );
651
652 #ifdef DEBUG_HINTER
653 if ( ps_debug_hint_func )
654 ps_debug_hint_func( hint, dimension );
655 #endif
656 }
657 }
658
659
660 #if 0 /* not used for now, experimental */
661
662 /*
663 * A variant to perform "light" hinting (i.e. FT_RENDER_MODE_LIGHT)
664 * of stems
665 */
666 static void
667 psh_hint_align_light( PSH_Hint hint,
668 PSH_Globals globals,
669 FT_Int dimension,
670 PSH_Glyph glyph )
671 {
672 PSH_Dimension dim = &globals->dimension[dimension];
673 FT_Fixed scale = dim->scale_mult;
674 FT_Fixed delta = dim->scale_delta;
675
676
677 if ( !psh_hint_is_fitted( hint ) )
678 {
679 FT_Pos pos = FT_MulFix( hint->org_pos, scale ) + delta;
680 FT_Pos len = FT_MulFix( hint->org_len, scale );
681
682 FT_Pos fit_len;
683
684 PSH_AlignmentRec align;
685
686
687 /* ignore stem alignments when requested through the hint flags */
688 if ( ( dimension == 0 && !glyph->do_horz_hints ) ||
689 ( dimension == 1 && !glyph->do_vert_hints ) )
690 {
691 hint->cur_pos = pos;
692 hint->cur_len = len;
693
694 psh_hint_set_fitted( hint );
695 return;
696 }
697
698 fit_len = len;
699
700 hint->cur_len = fit_len;
701
702 /* check blue zones for horizontal stems */
703 align.align = PSH_BLUE_ALIGN_NONE;
704 align.align_bot = align.align_top = 0;
705
706 if ( dimension == 1 )
707 psh_blues_snap_stem( &globals->blues,
708 hint->org_pos + hint->org_len,
709 hint->org_pos,
710 &align );
711
712 switch ( align.align )
713 {
714 case PSH_BLUE_ALIGN_TOP:
715 /* the top of the stem is aligned against a blue zone */
716 hint->cur_pos = align.align_top - fit_len;
717 break;
718
719 case PSH_BLUE_ALIGN_BOT:
720 /* the bottom of the stem is aligned against a blue zone */
721 hint->cur_pos = align.align_bot;
722 break;
723
724 case PSH_BLUE_ALIGN_TOP | PSH_BLUE_ALIGN_BOT:
725 /* both edges of the stem are aligned against blue zones */
726 hint->cur_pos = align.align_bot;
727 hint->cur_len = align.align_top - align.align_bot;
728 break;
729
730 default:
731 {
732 PSH_Hint parent = hint->parent;
733
734
735 if ( parent )
736 {
737 FT_Pos par_org_center, par_cur_center;
738 FT_Pos cur_org_center, cur_delta;
739
740
741 /* ensure that parent is already fitted */
742 if ( !psh_hint_is_fitted( parent ) )
743 psh_hint_align_light( parent, globals, dimension, glyph );
744
745 par_org_center = parent->org_pos + ( parent->org_len / 2 );
746 par_cur_center = parent->cur_pos + ( parent->cur_len / 2 );
747 cur_org_center = hint->org_pos + ( hint->org_len / 2 );
748
749 cur_delta = FT_MulFix( cur_org_center - par_org_center, scale );
750 pos = par_cur_center + cur_delta - ( len >> 1 );
751 }
752
753 /* Stems less than one pixel wide are easy -- we want to
754 * make them as dark as possible, so they must fall within
755 * one pixel. If the stem is split between two pixels
756 * then snap the edge that is nearer to the pixel boundary
757 * to the pixel boundary.
758 */
759 if ( len <= 64 )
760 {
761 if ( ( pos + len + 63 ) / 64 != pos / 64 + 1 )
762 pos += psh_hint_snap_stem_side_delta ( pos, len );
763 }
764
765 /* Position stems other to minimize the amount of mid-grays.
766 * There are, in general, two positions that do this,
767 * illustrated as A) and B) below.
768 *
769 * + + + +
770 *
771 * A) |--------------------------------|
772 * B) |--------------------------------|
773 * C) |--------------------------------|
774 *
775 * Position A) (split the excess stem equally) should be better
776 * for stems of width N + f where f < 0.5.
777 *
778 * Position B) (split the deficiency equally) should be better
779 * for stems of width N + f where f > 0.5.
780 *
781 * It turns out though that minimizing the total number of lit
782 * pixels is also important, so position C), with one edge
783 * aligned with a pixel boundary is actually preferable
784 * to A). There are also more possibile positions for C) than
785 * for A) or B), so it involves less distortion of the overall
786 * character shape.
787 */
788 else /* len > 64 */
789 {
790 FT_Fixed frac_len = len & 63;
791 FT_Fixed center = pos + ( len >> 1 );
792 FT_Fixed delta_a, delta_b;
793
794
795 if ( ( len / 64 ) & 1 )
796 {
797 delta_a = FT_PIX_FLOOR( center ) + 32 - center;
798 delta_b = FT_PIX_ROUND( center ) - center;
799 }
800 else
801 {
802 delta_a = FT_PIX_ROUND( center ) - center;
803 delta_b = FT_PIX_FLOOR( center ) + 32 - center;
804 }
805
806 /* We choose between B) and C) above based on the amount
807 * of fractinal stem width; for small amounts, choose
808 * C) always, for large amounts, B) always, and inbetween,
809 * pick whichever one involves less stem movement.
810 */
811 if ( frac_len < 32 )
812 {
813 pos += psh_hint_snap_stem_side_delta ( pos, len );
814 }
815 else if ( frac_len < 48 )
816 {
817 FT_Fixed side_delta = psh_hint_snap_stem_side_delta ( pos,
818 len );
819
820 if ( FT_ABS( side_delta ) < FT_ABS( delta_b ) )
821 pos += side_delta;
822 else
823 pos += delta_b;
824 }
825 else
826 {
827 pos += delta_b;
828 }
829 }
830
831 hint->cur_pos = pos;
832 }
833 } /* switch */
834
835 psh_hint_set_fitted( hint );
836
837 #ifdef DEBUG_HINTER
838 if ( ps_debug_hint_func )
839 ps_debug_hint_func( hint, dimension );
840 #endif
841 }
842 }
843
844 #endif /* 0 */
845
846
847 static void
848 psh_hint_table_align_hints( PSH_Hint_Table table,
849 PSH_Globals globals,
850 FT_Int dimension,
851 PSH_Glyph glyph )
852 {
853 PSH_Hint hint;
854 FT_UInt count;
855
856 #ifdef DEBUG_HINTER
857
858 PSH_Dimension dim = &globals->dimension[dimension];
859 FT_Fixed scale = dim->scale_mult;
860 FT_Fixed delta = dim->scale_delta;
861
862
863 if ( ps_debug_no_vert_hints && dimension == 0 )
864 {
865 ps_simple_scale( table, scale, delta, dimension );
866 return;
867 }
868
869 if ( ps_debug_no_horz_hints && dimension == 1 )
870 {
871 ps_simple_scale( table, scale, delta, dimension );
872 return;
873 }
874
875 #endif /* DEBUG_HINTER*/
876
877 hint = table->hints;
878 count = table->max_hints;
879
880 for ( ; count > 0; count--, hint++ )
881 psh_hint_align( hint, globals, dimension, glyph );
882 }
883
884
885 /*************************************************************************/
886 /*************************************************************************/
887 /***** *****/
888 /***** POINTS INTERPOLATION ROUTINES *****/
889 /***** *****/
890 /*************************************************************************/
891 /*************************************************************************/
892
893 #define PSH_ZONE_MIN -3200000L
894 #define PSH_ZONE_MAX +3200000L
895
896 #define xxDEBUG_ZONES
897
898
899 #ifdef DEBUG_ZONES
900
901 #include FT_CONFIG_STANDARD_LIBRARY_H
902
903 static void
904 psh_print_zone( PSH_Zone zone )
905 {
906 printf( "zone [scale,delta,min,max] = [%.3f,%.3f,%d,%d]\n",
907 zone->scale / 65536.0,
908 zone->delta / 64.0,
909 zone->min,
910 zone->max );
911 }
912
913 #else
914
915 #define psh_print_zone( x ) do { } while ( 0 )
916
917 #endif /* DEBUG_ZONES */
918
919
920 /*************************************************************************/
921 /*************************************************************************/
922 /***** *****/
923 /***** HINTER GLYPH MANAGEMENT *****/
924 /***** *****/
925 /*************************************************************************/
926 /*************************************************************************/
927
928 #if 1
929
930 #define psh_corner_is_flat ft_corner_is_flat
931 #define psh_corner_orientation ft_corner_orientation
932
933 #else
934
935 FT_LOCAL_DEF( FT_Int )
936 psh_corner_is_flat( FT_Pos x_in,
937 FT_Pos y_in,
938 FT_Pos x_out,
939 FT_Pos y_out )
940 {
941 FT_Pos ax = x_in;
942 FT_Pos ay = y_in;
943
944 FT_Pos d_in, d_out, d_corner;
945
946
947 if ( ax < 0 )
948 ax = -ax;
949 if ( ay < 0 )
950 ay = -ay;
951 d_in = ax + ay;
952
953 ax = x_out;
954 if ( ax < 0 )
955 ax = -ax;
956 ay = y_out;
957 if ( ay < 0 )
958 ay = -ay;
959 d_out = ax + ay;
960
961 ax = x_out + x_in;
962 if ( ax < 0 )
963 ax = -ax;
964 ay = y_out + y_in;
965 if ( ay < 0 )
966 ay = -ay;
967 d_corner = ax + ay;
968
969 return ( d_in + d_out - d_corner ) < ( d_corner >> 4 );
970 }
971
972 static FT_Int
973 psh_corner_orientation( FT_Pos in_x,
974 FT_Pos in_y,
975 FT_Pos out_x,
976 FT_Pos out_y )
977 {
978 FT_Int result;
979
980
981 /* deal with the trivial cases quickly */
982 if ( in_y == 0 )
983 {
984 if ( in_x >= 0 )
985 result = out_y;
986 else
987 result = -out_y;
988 }
989 else if ( in_x == 0 )
990 {
991 if ( in_y >= 0 )
992 result = -out_x;
993 else
994 result = out_x;
995 }
996 else if ( out_y == 0 )
997 {
998 if ( out_x >= 0 )
999 result = in_y;
1000 else
1001 result = -in_y;
1002 }
1003 else if ( out_x == 0 )
1004 {
1005 if ( out_y >= 0 )
1006 result = -in_x;
1007 else
1008 result = in_x;
1009 }
1010 else /* general case */
1011 {
1012 long long delta = (long long)in_x * out_y - (long long)in_y * out_x;
1013
1014 if ( delta == 0 )
1015 result = 0;
1016 else
1017 result = 1 - 2 * ( delta < 0 );
1018 }
1019
1020 return result;
1021 }
1022
1023 #endif /* !1 */
1024
1025
1026 #ifdef COMPUTE_INFLEXS
1027
1028 /* compute all inflex points in a given glyph */
1029 static void
1030 psh_glyph_compute_inflections( PSH_Glyph glyph )
1031 {
1032 FT_UInt n;
1033
1034
1035 for ( n = 0; n < glyph->num_contours; n++ )
1036 {
1037 PSH_Point first, start, end, before, after;
1038 FT_Pos in_x, in_y, out_x, out_y;
1039 FT_Int orient_prev, orient_cur;
1040 FT_Int finished = 0;
1041
1042
1043 /* we need at least 4 points to create an inflection point */
1044 if ( glyph->contours[n].count < 4 )
1045 continue;
1046
1047 /* compute first segment in contour */
1048 first = glyph->contours[n].start;
1049
1050 start = end = first;
1051 do
1052 {
1053 end = end->next;
1054 if ( end == first )
1055 goto Skip;
1056
1057 in_x = end->org_u - start->org_u;
1058 in_y = end->org_v - start->org_v;
1059
1060 } while ( in_x == 0 && in_y == 0 );
1061
1062 /* extend the segment start whenever possible */
1063 before = start;
1064 do
1065 {
1066 do
1067 {
1068 start = before;
1069 before = before->prev;
1070 if ( before == first )
1071 goto Skip;
1072
1073 out_x = start->org_u - before->org_u;
1074 out_y = start->org_v - before->org_v;
1075
1076 } while ( out_x == 0 && out_y == 0 );
1077
1078 orient_prev = psh_corner_orientation( in_x, in_y, out_x, out_y );
1079
1080 } while ( orient_prev == 0 );
1081
1082 first = start;
1083 in_x = out_x;
1084 in_y = out_y;
1085
1086 /* now, process all segments in the contour */
1087 do
1088 {
1089 /* first, extend current segment's end whenever possible */
1090 after = end;
1091 do
1092 {
1093 do
1094 {
1095 end = after;
1096 after = after->next;
1097 if ( after == first )
1098 finished = 1;
1099
1100 out_x = after->org_u - end->org_u;
1101 out_y = after->org_v - end->org_v;
1102
1103 } while ( out_x == 0 && out_y == 0 );
1104
1105 orient_cur = psh_corner_orientation( in_x, in_y, out_x, out_y );
1106
1107 } while ( orient_cur == 0 );
1108
1109 if ( ( orient_cur ^ orient_prev ) < 0 )
1110 {
1111 do
1112 {
1113 psh_point_set_inflex( start );
1114 start = start->next;
1115 }
1116 while ( start != end );
1117
1118 psh_point_set_inflex( start );
1119 }
1120
1121 start = end;
1122 end = after;
1123 orient_prev = orient_cur;
1124 in_x = out_x;
1125 in_y = out_y;
1126
1127 } while ( !finished );
1128
1129 Skip:
1130 ;
1131 }
1132 }
1133
1134 #endif /* COMPUTE_INFLEXS */
1135
1136
1137 static void
1138 psh_glyph_done( PSH_Glyph glyph )
1139 {
1140 FT_Memory memory = glyph->memory;
1141
1142
1143 psh_hint_table_done( &glyph->hint_tables[1], memory );
1144 psh_hint_table_done( &glyph->hint_tables[0], memory );
1145
1146 FT_FREE( glyph->points );
1147 FT_FREE( glyph->contours );
1148
1149 glyph->num_points = 0;
1150 glyph->num_contours = 0;
1151
1152 glyph->memory = 0;
1153 }
1154
1155
1156 static int
1157 psh_compute_dir( FT_Pos dx,
1158 FT_Pos dy )
1159 {
1160 FT_Pos ax, ay;
1161 int result = PSH_DIR_NONE;
1162
1163
1164 ax = FT_ABS( dx );
1165 ay = FT_ABS( dy );
1166
1167 if ( ay * 12 < ax )
1168 {
1169 /* |dy| <<< |dx| means a near-horizontal segment */
1170 result = ( dx >= 0 ) ? PSH_DIR_RIGHT : PSH_DIR_LEFT;
1171 }
1172 else if ( ax * 12 < ay )
1173 {
1174 /* |dx| <<< |dy| means a near-vertical segment */
1175 result = ( dy >= 0 ) ? PSH_DIR_UP : PSH_DIR_DOWN;
1176 }
1177
1178 return result;
1179 }
1180
1181
1182 /* load outline point coordinates into hinter glyph */
1183 static void
1184 psh_glyph_load_points( PSH_Glyph glyph,
1185 FT_Int dimension )
1186 {
1187 FT_Vector* vec = glyph->outline->points;
1188 PSH_Point point = glyph->points;
1189 FT_UInt count = glyph->num_points;
1190
1191
1192 for ( ; count > 0; count--, point++, vec++ )
1193 {
1194 point->flags2 = 0;
1195 point->hint = NULL;
1196 if ( dimension == 0 )
1197 {
1198 point->org_u = vec->x;
1199 point->org_v = vec->y;
1200 }
1201 else
1202 {
1203 point->org_u = vec->y;
1204 point->org_v = vec->x;
1205 }
1206
1207 #ifdef DEBUG_HINTER
1208 point->org_x = vec->x;
1209 point->org_y = vec->y;
1210 #endif
1211
1212 }
1213 }
1214
1215
1216 /* save hinted point coordinates back to outline */
1217 static void
1218 psh_glyph_save_points( PSH_Glyph glyph,
1219 FT_Int dimension )
1220 {
1221 FT_UInt n;
1222 PSH_Point point = glyph->points;
1223 FT_Vector* vec = glyph->outline->points;
1224 char* tags = glyph->outline->tags;
1225
1226
1227 for ( n = 0; n < glyph->num_points; n++ )
1228 {
1229 if ( dimension == 0 )
1230 vec[n].x = point->cur_u;
1231 else
1232 vec[n].y = point->cur_u;
1233
1234 if ( psh_point_is_strong( point ) )
1235 tags[n] |= (char)( ( dimension == 0 ) ? 32 : 64 );
1236
1237 #ifdef DEBUG_HINTER
1238
1239 if ( dimension == 0 )
1240 {
1241 point->cur_x = point->cur_u;
1242 point->flags_x = point->flags2 | point->flags;
1243 }
1244 else
1245 {
1246 point->cur_y = point->cur_u;
1247 point->flags_y = point->flags2 | point->flags;
1248 }
1249
1250 #endif
1251
1252 point++;
1253 }
1254 }
1255
1256
1257 static FT_Error
1258 psh_glyph_init( PSH_Glyph glyph,
1259 FT_Outline* outline,
1260 PS_Hints ps_hints,
1261 PSH_Globals globals )
1262 {
1263 FT_Error error;
1264 FT_Memory memory;
1265
1266
1267 /* clear all fields */
1268 FT_MEM_ZERO( glyph, sizeof ( *glyph ) );
1269
1270 memory = glyph->memory = globals->memory;
1271
1272 /* allocate and setup points + contours arrays */
1273 if ( FT_NEW_ARRAY( glyph->points, outline->n_points ) ||
1274 FT_NEW_ARRAY( glyph->contours, outline->n_contours ) )
1275 goto Exit;
1276
1277 glyph->num_points = outline->n_points;
1278 glyph->num_contours = outline->n_contours;
1279
1280 {
1281 FT_UInt first = 0, next, n;
1282 PSH_Point points = glyph->points;
1283 PSH_Contour contour = glyph->contours;
1284
1285
1286 for ( n = 0; n < glyph->num_contours; n++ )
1287 {
1288 FT_Int count;
1289 PSH_Point point;
1290
1291
1292 next = outline->contours[n] + 1;
1293 count = next - first;
1294
1295 contour->start = points + first;
1296 contour->count = (FT_UInt)count;
1297
1298 if ( count > 0 )
1299 {
1300 point = points + first;
1301
1302 point->prev = points + next - 1;
1303 point->contour = contour;
1304
1305 for ( ; count > 1; count-- )
1306 {
1307 point[0].next = point + 1;
1308 point[1].prev = point;
1309 point++;
1310 point->contour = contour;
1311 }
1312 point->next = points + first;
1313 }
1314
1315 contour++;
1316 first = next;
1317 }
1318 }
1319
1320 {
1321 PSH_Point points = glyph->points;
1322 PSH_Point point = points;
1323 FT_Vector* vec = outline->points;
1324 FT_UInt n;
1325
1326
1327 for ( n = 0; n < glyph->num_points; n++, point++ )
1328 {
1329 FT_Int n_prev = (FT_Int)( point->prev - points );
1330 FT_Int n_next = (FT_Int)( point->next - points );
1331 FT_Pos dxi, dyi, dxo, dyo;
1332
1333
1334 if ( !( outline->tags[n] & FT_CURVE_TAG_ON ) )
1335 point->flags = PSH_POINT_OFF;
1336
1337 dxi = vec[n].x - vec[n_prev].x;
1338 dyi = vec[n].y - vec[n_prev].y;
1339
1340 point->dir_in = (FT_Char)psh_compute_dir( dxi, dyi );
1341
1342 dxo = vec[n_next].x - vec[n].x;
1343 dyo = vec[n_next].y - vec[n].y;
1344
1345 point->dir_out = (FT_Char)psh_compute_dir( dxo, dyo );
1346
1347 /* detect smooth points */
1348 if ( point->flags & PSH_POINT_OFF )
1349 point->flags |= PSH_POINT_SMOOTH;
1350
1351 else if ( point->dir_in == point->dir_out )
1352 {
1353 if ( point->dir_out != PSH_DIR_NONE ||
1354 psh_corner_is_flat( dxi, dyi, dxo, dyo ) )
1355 point->flags |= PSH_POINT_SMOOTH;
1356 }
1357 }
1358 }
1359
1360 glyph->outline = outline;
1361 glyph->globals = globals;
1362
1363 #ifdef COMPUTE_INFLEXS
1364 psh_glyph_load_points( glyph, 0 );
1365 psh_glyph_compute_inflections( glyph );
1366 #endif /* COMPUTE_INFLEXS */
1367
1368 /* now deal with hints tables */
1369 error = psh_hint_table_init( &glyph->hint_tables [0],
1370 &ps_hints->dimension[0].hints,
1371 &ps_hints->dimension[0].masks,
1372 &ps_hints->dimension[0].counters,
1373 memory );
1374 if ( error )
1375 goto Exit;
1376
1377 error = psh_hint_table_init( &glyph->hint_tables [1],
1378 &ps_hints->dimension[1].hints,
1379 &ps_hints->dimension[1].masks,
1380 &ps_hints->dimension[1].counters,
1381 memory );
1382 if ( error )
1383 goto Exit;
1384
1385 Exit:
1386 return error;
1387 }
1388
1389
1390 /* compute all extrema in a glyph for a given dimension */
1391 static void
1392 psh_glyph_compute_extrema( PSH_Glyph glyph )
1393 {
1394 FT_UInt n;
1395
1396
1397 /* first of all, compute all local extrema */
1398 for ( n = 0; n < glyph->num_contours; n++ )
1399 {
1400 PSH_Point first = glyph->contours[n].start;
1401 PSH_Point point, before, after;
1402
1403
1404 if ( glyph->contours[n].count == 0 )
1405 continue;
1406
1407 point = first;
1408 before = point;
1409
1410 do
1411 {
1412 before = before->prev;
1413 if ( before == first )
1414 goto Skip;
1415
1416 } while ( before->org_u == point->org_u );
1417
1418 first = point = before->next;
1419
1420 for (;;)
1421 {
1422 after = point;
1423 do
1424 {
1425 after = after->next;
1426 if ( after == first )
1427 goto Next;
1428
1429 } while ( after->org_u == point->org_u );
1430
1431 if ( before->org_u < point->org_u )
1432 {
1433 if ( after->org_u < point->org_u )
1434 {
1435 /* local maximum */
1436 goto Extremum;
1437 }
1438 }
1439 else /* before->org_u > point->org_u */
1440 {
1441 if ( after->org_u > point->org_u )
1442 {
1443 /* local minimum */
1444 Extremum:
1445 do
1446 {
1447 psh_point_set_extremum( point );
1448 point = point->next;
1449
1450 } while ( point != after );
1451 }
1452 }
1453
1454 before = after->prev;
1455 point = after;
1456
1457 } /* for */
1458
1459 Next:
1460 ;
1461 }
1462
1463 /* for each extremum, determine its direction along the */
1464 /* orthogonal axis */
1465 for ( n = 0; n < glyph->num_points; n++ )
1466 {
1467 PSH_Point point, before, after;
1468
1469
1470 point = &glyph->points[n];
1471 before = point;
1472 after = point;
1473
1474 if ( psh_point_is_extremum( point ) )
1475 {
1476 do
1477 {
1478 before = before->prev;
1479 if ( before == point )
1480 goto Skip;
1481
1482 } while ( before->org_v == point->org_v );
1483
1484 do
1485 {
1486 after = after->next;
1487 if ( after == point )
1488 goto Skip;
1489
1490 } while ( after->org_v == point->org_v );
1491 }
1492
1493 if ( before->org_v < point->org_v &&
1494 after->org_v > point->org_v )
1495 {
1496 psh_point_set_positive( point );
1497 }
1498 else if ( before->org_v > point->org_v &&
1499 after->org_v < point->org_v )
1500 {
1501 psh_point_set_negative( point );
1502 }
1503
1504 Skip:
1505 ;
1506 }
1507 }
1508
1509
1510 /* major_dir is the direction for points on the bottom/left of the stem; */
1511 /* Points on the top/right of the stem will have a direction of */
1512 /* -major_dir. */
1513
1514 static void
1515 psh_hint_table_find_strong_points( PSH_Hint_Table table,
1516 PSH_Point point,
1517 FT_UInt count,
1518 FT_Int threshold,
1519 FT_Int major_dir )
1520 {
1521 PSH_Hint* sort = table->sort;
1522 FT_UInt num_hints = table->num_hints;
1523
1524
1525 for ( ; count > 0; count--, point++ )
1526 {
1527 FT_Int point_dir = 0;
1528 FT_Pos org_u = point->org_u;
1529
1530
1531 if ( psh_point_is_strong( point ) )
1532 continue;
1533
1534 if ( PSH_DIR_COMPARE( point->dir_in, major_dir ) )
1535 point_dir = point->dir_in;
1536
1537 else if ( PSH_DIR_COMPARE( point->dir_out, major_dir ) )
1538 point_dir = point->dir_out;
1539
1540 if ( point_dir )
1541 {
1542 if ( point_dir == major_dir )
1543 {
1544 FT_UInt nn;
1545
1546
1547 for ( nn = 0; nn < num_hints; nn++ )
1548 {
1549 PSH_Hint hint = sort[nn];
1550 FT_Pos d = org_u - hint->org_pos;
1551
1552
1553 if ( d < threshold && -d < threshold )
1554 {
1555 psh_point_set_strong( point );
1556 point->flags2 |= PSH_POINT_EDGE_MIN;
1557 point->hint = hint;
1558 break;
1559 }
1560 }
1561 }
1562 else if ( point_dir == -major_dir )
1563 {
1564 FT_UInt nn;
1565
1566
1567 for ( nn = 0; nn < num_hints; nn++ )
1568 {
1569 PSH_Hint hint = sort[nn];
1570 FT_Pos d = org_u - hint->org_pos - hint->org_len;
1571
1572
1573 if ( d < threshold && -d < threshold )
1574 {
1575 psh_point_set_strong( point );
1576 point->flags2 |= PSH_POINT_EDGE_MAX;
1577 point->hint = hint;
1578 break;
1579 }
1580 }
1581 }
1582 }
1583
1584 #if 1
1585 else if ( psh_point_is_extremum( point ) )
1586 {
1587 /* treat extrema as special cases for stem edge alignment */
1588 FT_UInt nn, min_flag, max_flag;
1589
1590
1591 if ( major_dir == PSH_DIR_HORIZONTAL )
1592 {
1593 min_flag = PSH_POINT_POSITIVE;
1594 max_flag = PSH_POINT_NEGATIVE;
1595 }
1596 else
1597 {
1598 min_flag = PSH_POINT_NEGATIVE;
1599 max_flag = PSH_POINT_POSITIVE;
1600 }
1601
1602 if ( point->flags2 & min_flag )
1603 {
1604 for ( nn = 0; nn < num_hints; nn++ )
1605 {
1606 PSH_Hint hint = sort[nn];
1607 FT_Pos d = org_u - hint->org_pos;
1608
1609
1610 if ( d < threshold && -d < threshold )
1611 {
1612 point->flags2 |= PSH_POINT_EDGE_MIN;
1613 point->hint = hint;
1614 psh_point_set_strong( point );
1615 break;
1616 }
1617 }
1618 }
1619 else if ( point->flags2 & max_flag )
1620 {
1621 for ( nn = 0; nn < num_hints; nn++ )
1622 {
1623 PSH_Hint hint = sort[nn];
1624 FT_Pos d = org_u - hint->org_pos - hint->org_len;
1625
1626
1627 if ( d < threshold && -d < threshold )
1628 {
1629 point->flags2 |= PSH_POINT_EDGE_MAX;
1630 point->hint = hint;
1631 psh_point_set_strong( point );
1632 break;
1633 }
1634 }
1635 }
1636
1637 if ( point->hint == NULL )
1638 {
1639 for ( nn = 0; nn < num_hints; nn++ )
1640 {
1641 PSH_Hint hint = sort[nn];
1642
1643
1644 if ( org_u >= hint->org_pos &&
1645 org_u <= hint->org_pos + hint->org_len )
1646 {
1647 point->hint = hint;
1648 break;
1649 }
1650 }
1651 }
1652 }
1653
1654 #endif /* 1 */
1655 }
1656 }
1657
1658
1659 /* the accepted shift for strong points in fractional pixels */
1660 #define PSH_STRONG_THRESHOLD 32
1661
1662 /* the maximum shift value in font units */
1663 #define PSH_STRONG_THRESHOLD_MAXIMUM 30
1664
1665
1666 /* find strong points in a glyph */
1667 static void
1668 psh_glyph_find_strong_points( PSH_Glyph glyph,
1669 FT_Int dimension )
1670 {
1671 /* a point is `strong' if it is located on a stem edge and */
1672 /* has an `in' or `out' tangent parallel to the hint's direction */
1673
1674 PSH_Hint_Table table = &glyph->hint_tables[dimension];
1675 PS_Mask mask = table->hint_masks->masks;
1676 FT_UInt num_masks = table->hint_masks->num_masks;
1677 FT_UInt first = 0;
1678 FT_Int major_dir = dimension == 0 ? PSH_DIR_VERTICAL
1679 : PSH_DIR_HORIZONTAL;
1680 PSH_Dimension dim = &glyph->globals->dimension[dimension];
1681 FT_Fixed scale = dim->scale_mult;
1682 FT_Int threshold;
1683
1684
1685 threshold = (FT_Int)FT_DivFix( PSH_STRONG_THRESHOLD, scale );
1686 if ( threshold > PSH_STRONG_THRESHOLD_MAXIMUM )
1687 threshold = PSH_STRONG_THRESHOLD_MAXIMUM;
1688
1689 /* process secondary hints to `selected' points */
1690 if ( num_masks > 1 && glyph->num_points > 0 )
1691 {
1692 /* the `endchar' op can reduce the number of points */
1693 first = mask->end_point > glyph->num_points
1694 ? glyph->num_points
1695 : mask->end_point;
1696 mask++;
1697 for ( ; num_masks > 1; num_masks--, mask++ )
1698 {
1699 FT_UInt next;
1700 FT_Int count;
1701
1702
1703 next = mask->end_point > glyph->num_points
1704 ? glyph->num_points
1705 : mask->end_point;
1706 count = next - first;
1707 if ( count > 0 )
1708 {
1709 PSH_Point point = glyph->points + first;
1710
1711
1712 psh_hint_table_activate_mask( table, mask );
1713
1714 psh_hint_table_find_strong_points( table, point, count,
1715 threshold, major_dir );
1716 }
1717 first = next;
1718 }
1719 }
1720
1721 /* process primary hints for all points */
1722 if ( num_masks == 1 )
1723 {
1724 FT_UInt count = glyph->num_points;
1725 PSH_Point point = glyph->points;
1726
1727
1728 psh_hint_table_activate_mask( table, table->hint_masks->masks );
1729
1730 psh_hint_table_find_strong_points( table, point, count,
1731 threshold, major_dir );
1732 }
1733
1734 /* now, certain points may have been attached to a hint and */
1735 /* not marked as strong; update their flags then */
1736 {
1737 FT_UInt count = glyph->num_points;
1738 PSH_Point point = glyph->points;
1739
1740
1741 for ( ; count > 0; count--, point++ )
1742 if ( point->hint && !psh_point_is_strong( point ) )
1743 psh_point_set_strong( point );
1744 }
1745 }
1746
1747
1748 /* find points in a glyph which are in a blue zone and have `in' or */
1749 /* `out' tangents parallel to the horizontal axis */
1750 static void
1751 psh_glyph_find_blue_points( PSH_Blues blues,
1752 PSH_Glyph glyph )
1753 {
1754 PSH_Blue_Table table;
1755 PSH_Blue_Zone zone;
1756 FT_UInt glyph_count = glyph->num_points;
1757 FT_UInt blue_count;
1758 PSH_Point point = glyph->points;
1759
1760
1761 for ( ; glyph_count > 0; glyph_count--, point++ )
1762 {
1763 FT_Pos y;
1764
1765
1766 /* check tangents */
1767 if ( !PSH_DIR_COMPARE( point->dir_in, PSH_DIR_HORIZONTAL ) &&
1768 !PSH_DIR_COMPARE( point->dir_out, PSH_DIR_HORIZONTAL ) )
1769 continue;
1770
1771 /* skip strong points */
1772 if ( psh_point_is_strong( point ) )
1773 continue;
1774
1775 y = point->org_u;
1776
1777 /* look up top zones */
1778 table = &blues->normal_top;
1779 blue_count = table->count;
1780 zone = table->zones;
1781
1782 for ( ; blue_count > 0; blue_count--, zone++ )
1783 {
1784 FT_Pos delta = y - zone->org_bottom;
1785
1786
1787 if ( delta < -blues->blue_fuzz )
1788 break;
1789
1790 if ( y <= zone->org_top + blues->blue_fuzz )
1791 if ( blues->no_overshoots || delta <= blues->blue_threshold )
1792 {
1793 point->cur_u = zone->cur_bottom;
1794 psh_point_set_strong( point );
1795 psh_point_set_fitted( point );
1796 }
1797 }
1798
1799 /* look up bottom zones */
1800 table = &blues->normal_bottom;
1801 blue_count = table->count;
1802 zone = table->zones + blue_count - 1;
1803
1804 for ( ; blue_count > 0; blue_count--, zone-- )
1805 {
1806 FT_Pos delta = zone->org_top - y;
1807
1808
1809 if ( delta < -blues->blue_fuzz )
1810 break;
1811
1812 if ( y >= zone->org_bottom - blues->blue_fuzz )
1813 if ( blues->no_overshoots || delta < blues->blue_threshold )
1814 {
1815 point->cur_u = zone->cur_top;
1816 psh_point_set_strong( point );
1817 psh_point_set_fitted( point );
1818 }
1819 }
1820 }
1821 }
1822
1823
1824 /* interpolate strong points with the help of hinted coordinates */
1825 static void
1826 psh_glyph_interpolate_strong_points( PSH_Glyph glyph,
1827 FT_Int dimension )
1828 {
1829 PSH_Dimension dim = &glyph->globals->dimension[dimension];
1830 FT_Fixed scale = dim->scale_mult;
1831
1832 FT_UInt count = glyph->num_points;
1833 PSH_Point point = glyph->points;
1834
1835
1836 for ( ; count > 0; count--, point++ )
1837 {
1838 PSH_Hint hint = point->hint;
1839
1840
1841 if ( hint )
1842 {
1843 FT_Pos delta;
1844
1845
1846 if ( psh_point_is_edge_min( point ) )
1847 point->cur_u = hint->cur_pos;
1848
1849 else if ( psh_point_is_edge_max( point ) )
1850 point->cur_u = hint->cur_pos + hint->cur_len;
1851
1852 else
1853 {
1854 delta = point->org_u - hint->org_pos;
1855
1856 if ( delta <= 0 )
1857 point->cur_u = hint->cur_pos + FT_MulFix( delta, scale );
1858
1859 else if ( delta >= hint->org_len )
1860 point->cur_u = hint->cur_pos + hint->cur_len +
1861 FT_MulFix( delta - hint->org_len, scale );
1862
1863 else /* hint->org_len > 0 */
1864 point->cur_u = hint->cur_pos +
1865 FT_MulDiv( delta, hint->cur_len,
1866 hint->org_len );
1867 }
1868 psh_point_set_fitted( point );
1869 }
1870 }
1871 }
1872
1873
1874 #define PSH_MAX_STRONG_INTERNAL 16
1875
1876 static void
1877 psh_glyph_interpolate_normal_points( PSH_Glyph glyph,
1878 FT_Int dimension )
1879 {
1880
1881 #if 1
1882 /* first technique: a point is strong if it is a local extremum */
1883
1884 PSH_Dimension dim = &glyph->globals->dimension[dimension];
1885 FT_Fixed scale = dim->scale_mult;
1886 FT_Memory memory = glyph->memory;
1887
1888 PSH_Point* strongs = NULL;
1889 PSH_Point strongs_0[PSH_MAX_STRONG_INTERNAL];
1890 FT_UInt num_strongs = 0;
1891
1892 PSH_Point points = glyph->points;
1893 PSH_Point points_end = points + glyph->num_points;
1894 PSH_Point point;
1895
1896
1897 /* first count the number of strong points */
1898 for ( point = points; point < points_end; point++ )
1899 {
1900 if ( psh_point_is_strong( point ) )
1901 num_strongs++;
1902 }
1903
1904 if ( num_strongs == 0 ) /* nothing to do here */
1905 return;
1906
1907 /* allocate an array to store a list of points, */
1908 /* stored in increasing org_u order */
1909 if ( num_strongs <= PSH_MAX_STRONG_INTERNAL )
1910 strongs = strongs_0;
1911 else
1912 {
1913 FT_Error error;
1914
1915
1916 if ( FT_NEW_ARRAY( strongs, num_strongs ) )
1917 return;
1918 }
1919
1920 num_strongs = 0;
1921 for ( point = points; point < points_end; point++ )
1922 {
1923 PSH_Point* insert;
1924
1925
1926 if ( !psh_point_is_strong( point ) )
1927 continue;
1928
1929 for ( insert = strongs + num_strongs; insert > strongs; insert-- )
1930 {
1931 if ( insert[-1]->org_u <= point->org_u )
1932 break;
1933
1934 insert[0] = insert[-1];
1935 }
1936 insert[0] = point;
1937 num_strongs++;
1938 }
1939
1940 /* now try to interpolate all normal points */
1941 for ( point = points; point < points_end; point++ )
1942 {
1943 if ( psh_point_is_strong( point ) )
1944 continue;
1945
1946 /* sometimes, some local extrema are smooth points */
1947 if ( psh_point_is_smooth( point ) )
1948 {
1949 if ( point->dir_in == PSH_DIR_NONE ||
1950 point->dir_in != point->dir_out )
1951 continue;
1952
1953 if ( !psh_point_is_extremum( point ) &&
1954 !psh_point_is_inflex( point ) )
1955 continue;
1956
1957 point->flags &= ~PSH_POINT_SMOOTH;
1958 }
1959
1960 /* find best enclosing point coordinates then interpolate */
1961 {
1962 PSH_Point before, after;
1963 FT_UInt nn;
1964
1965
1966 for ( nn = 0; nn < num_strongs; nn++ )
1967 if ( strongs[nn]->org_u > point->org_u )
1968 break;
1969
1970 if ( nn == 0 ) /* point before the first strong point */
1971 {
1972 after = strongs[0];
1973
1974 point->cur_u = after->cur_u +
1975 FT_MulFix( point->org_u - after->org_u,
1976 scale );
1977 }
1978 else
1979 {
1980 before = strongs[nn - 1];
1981
1982 for ( nn = num_strongs; nn > 0; nn-- )
1983 if ( strongs[nn - 1]->org_u < point->org_u )
1984 break;
1985
1986 if ( nn == num_strongs ) /* point is after last strong point */
1987 {
1988 before = strongs[nn - 1];
1989
1990 point->cur_u = before->cur_u +
1991 FT_MulFix( point->org_u - before->org_u,
1992 scale );
1993 }
1994 else
1995 {
1996 FT_Pos u;
1997
1998
1999 after = strongs[nn];
2000
2001 /* now interpolate point between before and after */
2002 u = point->org_u;
2003
2004 if ( u == before->org_u )
2005 point->cur_u = before->cur_u;
2006
2007 else if ( u == after->org_u )
2008 point->cur_u = after->cur_u;
2009
2010 else
2011 point->cur_u = before->cur_u +
2012 FT_MulDiv( u - before->org_u,
2013 after->cur_u - before->cur_u,
2014 after->org_u - before->org_u );
2015 }
2016 }
2017 psh_point_set_fitted( point );
2018 }
2019 }
2020
2021 if ( strongs != strongs_0 )
2022 FT_FREE( strongs );
2023
2024 #endif /* 1 */
2025
2026 }
2027
2028
2029 /* interpolate other points */
2030 static void
2031 psh_glyph_interpolate_other_points( PSH_Glyph glyph,
2032 FT_Int dimension )
2033 {
2034 PSH_Dimension dim = &glyph->globals->dimension[dimension];
2035 FT_Fixed scale = dim->scale_mult;
2036 FT_Fixed delta = dim->scale_delta;
2037 PSH_Contour contour = glyph->contours;
2038 FT_UInt num_contours = glyph->num_contours;
2039
2040
2041 for ( ; num_contours > 0; num_contours--, contour++ )
2042 {
2043 PSH_Point start = contour->start;
2044 PSH_Point first, next, point;
2045 FT_UInt fit_count;
2046
2047
2048 /* count the number of strong points in this contour */
2049 next = start + contour->count;
2050 fit_count = 0;
2051 first = 0;
2052
2053 for ( point = start; point < next; point++ )
2054 if ( psh_point_is_fitted( point ) )
2055 {
2056 if ( !first )
2057 first = point;
2058
2059 fit_count++;
2060 }
2061
2062 /* if there are less than 2 fitted points in the contour, we */
2063 /* simply scale and eventually translate the contour points */
2064 if ( fit_count < 2 )
2065 {
2066 if ( fit_count == 1 )
2067 delta = first->cur_u - FT_MulFix( first->org_u, scale );
2068
2069 for ( point = start; point < next; point++ )
2070 if ( point != first )
2071 point->cur_u = FT_MulFix( point->org_u, scale ) + delta;
2072
2073 goto Next_Contour;
2074 }
2075
2076 /* there are more than 2 strong points in this contour; we */
2077 /* need to interpolate weak points between them */
2078 start = first;
2079 do
2080 {
2081 /* skip consecutive fitted points */
2082 for (;;)
2083 {
2084 next = first->next;
2085 if ( next == start )
2086 goto Next_Contour;
2087
2088 if ( !psh_point_is_fitted( next ) )
2089 break;
2090
2091 first = next;
2092 }
2093
2094 /* find next fitted point after unfitted one */
2095 for (;;)
2096 {
2097 next = next->next;
2098 if ( psh_point_is_fitted( next ) )
2099 break;
2100 }
2101
2102 /* now interpolate between them */
2103 {
2104 FT_Pos org_a, org_ab, cur_a, cur_ab;
2105 FT_Pos org_c, org_ac, cur_c;
2106 FT_Fixed scale_ab;
2107
2108
2109 if ( first->org_u <= next->org_u )
2110 {
2111 org_a = first->org_u;
2112 cur_a = first->cur_u;
2113 org_ab = next->org_u - org_a;
2114 cur_ab = next->cur_u - cur_a;
2115 }
2116 else
2117 {
2118 org_a = next->org_u;
2119 cur_a = next->cur_u;
2120 org_ab = first->org_u - org_a;
2121 cur_ab = first->cur_u - cur_a;
2122 }
2123
2124 scale_ab = 0x10000L;
2125 if ( org_ab > 0 )
2126 scale_ab = FT_DivFix( cur_ab, org_ab );
2127
2128 point = first->next;
2129 do
2130 {
2131 org_c = point->org_u;
2132 org_ac = org_c - org_a;
2133
2134 if ( org_ac <= 0 )
2135 {
2136 /* on the left of the interpolation zone */
2137 cur_c = cur_a + FT_MulFix( org_ac, scale );
2138 }
2139 else if ( org_ac >= org_ab )
2140 {
2141 /* on the right on the interpolation zone */
2142 cur_c = cur_a + cur_ab + FT_MulFix( org_ac - org_ab, scale );
2143 }
2144 else
2145 {
2146 /* within the interpolation zone */
2147 cur_c = cur_a + FT_MulFix( org_ac, scale_ab );
2148 }
2149
2150 point->cur_u = cur_c;
2151
2152 point = point->next;
2153
2154 } while ( point != next );
2155 }
2156
2157 /* keep going until all points in the contours have been processed */
2158 first = next;
2159
2160 } while ( first != start );
2161
2162 Next_Contour:
2163 ;
2164 }
2165 }
2166
2167
2168 /*************************************************************************/
2169 /*************************************************************************/
2170 /***** *****/
2171 /***** HIGH-LEVEL INTERFACE *****/
2172 /***** *****/
2173 /*************************************************************************/
2174 /*************************************************************************/
2175
2176 FT_Error
2177 ps_hints_apply( PS_Hints ps_hints,
2178 FT_Outline* outline,
2179 PSH_Globals globals,
2180 FT_Render_Mode hint_mode )
2181 {
2182 PSH_GlyphRec glyphrec;
2183 PSH_Glyph glyph = &glyphrec;
2184 FT_Error error;
2185 #ifdef DEBUG_HINTER
2186 FT_Memory memory;
2187 #endif
2188 FT_Int dimension;
2189
2190
2191 /* something to do? */
2192 if ( outline->n_points == 0 || outline->n_contours == 0 )
2193 return FT_Err_Ok;
2194
2195 #ifdef DEBUG_HINTER
2196
2197 memory = globals->memory;
2198
2199 if ( ps_debug_glyph )
2200 {
2201 psh_glyph_done( ps_debug_glyph );
2202 FT_FREE( ps_debug_glyph );
2203 }
2204
2205 if ( FT_NEW( glyph ) )
2206 return error;
2207
2208 ps_debug_glyph = glyph;
2209
2210 #endif /* DEBUG_HINTER */
2211
2212 error = psh_glyph_init( glyph, outline, ps_hints, globals );
2213 if ( error )
2214 goto Exit;
2215
2216 /* try to optimize the y_scale so that the top of non-capital letters
2217 * is aligned on a pixel boundary whenever possible
2218 */
2219 {
2220 PSH_Dimension dim_x = &glyph->globals->dimension[0];
2221 PSH_Dimension dim_y = &glyph->globals->dimension[1];
2222
2223 FT_Fixed x_scale = dim_x->scale_mult;
2224 FT_Fixed y_scale = dim_y->scale_mult;
2225
2226 FT_Fixed old_x_scale = x_scale;
2227 FT_Fixed old_y_scale = y_scale;
2228
2229 FT_Fixed scaled;
2230 FT_Fixed fitted;
2231
2232 FT_Bool rescale = FALSE;
2233
2234
2235 scaled = FT_MulFix( globals->blues.normal_top.zones->org_ref, y_scale );
2236 fitted = FT_PIX_ROUND( scaled );
2237
2238 if ( fitted != 0 && scaled != fitted )
2239 {
2240 rescale = TRUE;
2241
2242 y_scale = FT_MulDiv( y_scale, fitted, scaled );
2243
2244 if ( fitted < scaled )
2245 x_scale -= x_scale / 50;
2246
2247 psh_globals_set_scale( glyph->globals, x_scale, y_scale, 0, 0 );
2248 }
2249
2250 glyph->do_horz_hints = 1;
2251 glyph->do_vert_hints = 1;
2252
2253 glyph->do_horz_snapping = FT_BOOL( hint_mode == FT_RENDER_MODE_MONO ||
2254 hint_mode == FT_RENDER_MODE_LCD );
2255
2256 glyph->do_vert_snapping = FT_BOOL( hint_mode == FT_RENDER_MODE_MONO ||
2257 hint_mode == FT_RENDER_MODE_LCD_V );
2258
2259 glyph->do_stem_adjust = FT_BOOL( hint_mode != FT_RENDER_MODE_LIGHT );
2260
2261 for ( dimension = 0; dimension < 2; dimension++ )
2262 {
2263 /* load outline coordinates into glyph */
2264 psh_glyph_load_points( glyph, dimension );
2265
2266 /* compute local extrema */
2267 psh_glyph_compute_extrema( glyph );
2268
2269 /* compute aligned stem/hints positions */
2270 psh_hint_table_align_hints( &glyph->hint_tables[dimension],
2271 glyph->globals,
2272 dimension,
2273 glyph );
2274
2275 /* find strong points, align them, then interpolate others */
2276 psh_glyph_find_strong_points( glyph, dimension );
2277 if ( dimension == 1 )
2278 psh_glyph_find_blue_points( &globals->blues, glyph );
2279 psh_glyph_interpolate_strong_points( glyph, dimension );
2280 psh_glyph_interpolate_normal_points( glyph, dimension );
2281 psh_glyph_interpolate_other_points( glyph, dimension );
2282
2283 /* save hinted coordinates back to outline */
2284 psh_glyph_save_points( glyph, dimension );
2285
2286 if ( rescale )
2287 psh_globals_set_scale( glyph->globals,
2288 old_x_scale, old_y_scale, 0, 0 );
2289 }
2290 }
2291
2292 Exit:
2293
2294 #ifndef DEBUG_HINTER
2295 psh_glyph_done( glyph );
2296 #endif
2297
2298 return error;
2299 }
2300
2301
2302 /* END */
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