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[FREETYPE] Update to v2.6.3. CORE-10964
[reactos.git] / reactos / lib / 3rdparty / freetype / src / autofit / aflatin2.c
1 /***************************************************************************/
2 /* */
3 /* aflatin2.c */
4 /* */
5 /* Auto-fitter hinting routines for latin writing system (body). */
6 /* */
7 /* Copyright 2003-2016 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 FT_ADVANCES_H
20
21 #include "afglobal.h"
22 #include "aflatin.h"
23 #include "aflatin2.h"
24 #include "aferrors.h"
25
26
27 #ifdef AF_CONFIG_OPTION_USE_WARPER
28 #include "afwarp.h"
29 #endif
30
31
32 /*************************************************************************/
33 /* */
34 /* The macro FT_COMPONENT is used in trace mode. It is an implicit */
35 /* parameter of the FT_TRACE() and FT_ERROR() macros, used to print/log */
36 /* messages during execution. */
37 /* */
38 #undef FT_COMPONENT
39 #define FT_COMPONENT trace_aflatin2
40
41
42 FT_LOCAL_DEF( FT_Error )
43 af_latin2_hints_compute_segments( AF_GlyphHints hints,
44 AF_Dimension dim );
45
46 FT_LOCAL_DEF( void )
47 af_latin2_hints_link_segments( AF_GlyphHints hints,
48 AF_Dimension dim );
49
50 /*************************************************************************/
51 /*************************************************************************/
52 /***** *****/
53 /***** L A T I N G L O B A L M E T R I C S *****/
54 /***** *****/
55 /*************************************************************************/
56 /*************************************************************************/
57
58 FT_LOCAL_DEF( void )
59 af_latin2_metrics_init_widths( AF_LatinMetrics metrics,
60 FT_Face face )
61 {
62 /* scan the array of segments in each direction */
63 AF_GlyphHintsRec hints[1];
64
65
66 af_glyph_hints_init( hints, face->memory );
67
68 metrics->axis[AF_DIMENSION_HORZ].width_count = 0;
69 metrics->axis[AF_DIMENSION_VERT].width_count = 0;
70
71 {
72 FT_Error error;
73 FT_UInt glyph_index;
74 int dim;
75 AF_LatinMetricsRec dummy[1];
76 AF_Scaler scaler = &dummy->root.scaler;
77
78
79 glyph_index = FT_Get_Char_Index(
80 face,
81 metrics->root.style_class->standard_char );
82 if ( glyph_index == 0 )
83 goto Exit;
84
85 error = FT_Load_Glyph( face, glyph_index, FT_LOAD_NO_SCALE );
86 if ( error || face->glyph->outline.n_points <= 0 )
87 goto Exit;
88
89 FT_ZERO( dummy );
90
91 dummy->units_per_em = metrics->units_per_em;
92 scaler->x_scale = scaler->y_scale = 0x10000L;
93 scaler->x_delta = scaler->y_delta = 0;
94 scaler->face = face;
95 scaler->render_mode = FT_RENDER_MODE_NORMAL;
96 scaler->flags = 0;
97
98 af_glyph_hints_rescale( hints, (AF_StyleMetrics)dummy );
99
100 error = af_glyph_hints_reload( hints, &face->glyph->outline );
101 if ( error )
102 goto Exit;
103
104 for ( dim = 0; dim < AF_DIMENSION_MAX; dim++ )
105 {
106 AF_LatinAxis axis = &metrics->axis[dim];
107 AF_AxisHints axhints = &hints->axis[dim];
108 AF_Segment seg, limit, link;
109 FT_UInt num_widths = 0;
110
111
112 error = af_latin2_hints_compute_segments( hints,
113 (AF_Dimension)dim );
114 if ( error )
115 goto Exit;
116
117 af_latin2_hints_link_segments( hints,
118 (AF_Dimension)dim );
119
120 seg = axhints->segments;
121 limit = seg + axhints->num_segments;
122
123 for ( ; seg < limit; seg++ )
124 {
125 link = seg->link;
126
127 /* we only consider stem segments there! */
128 if ( link && link->link == seg && link > seg )
129 {
130 FT_Pos dist;
131
132
133 dist = seg->pos - link->pos;
134 if ( dist < 0 )
135 dist = -dist;
136
137 if ( num_widths < AF_LATIN_MAX_WIDTHS )
138 axis->widths[num_widths++].org = dist;
139 }
140 }
141
142 af_sort_widths( num_widths, axis->widths );
143 axis->width_count = num_widths;
144 }
145
146 Exit:
147 for ( dim = 0; dim < AF_DIMENSION_MAX; dim++ )
148 {
149 AF_LatinAxis axis = &metrics->axis[dim];
150 FT_Pos stdw;
151
152
153 stdw = ( axis->width_count > 0 )
154 ? axis->widths[0].org
155 : AF_LATIN_CONSTANT( metrics, 50 );
156
157 /* let's try 20% of the smallest width */
158 axis->edge_distance_threshold = stdw / 5;
159 axis->standard_width = stdw;
160 axis->extra_light = 0;
161 }
162 }
163
164 af_glyph_hints_done( hints );
165 }
166
167
168
169 #define AF_LATIN_MAX_TEST_CHARACTERS 12
170
171
172 static const char af_latin2_blue_chars[AF_LATIN_MAX_BLUES]
173 [AF_LATIN_MAX_TEST_CHARACTERS+1] =
174 {
175 "THEZOCQS",
176 "HEZLOCUS",
177 "fijkdbh",
178 "xzroesc",
179 "xzroesc",
180 "pqgjy"
181 };
182
183
184 static void
185 af_latin2_metrics_init_blues( AF_LatinMetrics metrics,
186 FT_Face face )
187 {
188 FT_Pos flats [AF_LATIN_MAX_TEST_CHARACTERS];
189 FT_Pos rounds[AF_LATIN_MAX_TEST_CHARACTERS];
190 FT_Int num_flats;
191 FT_Int num_rounds;
192 FT_Int bb;
193 AF_LatinBlue blue;
194 FT_Error error;
195 AF_LatinAxis axis = &metrics->axis[AF_DIMENSION_VERT];
196 FT_GlyphSlot glyph = face->glyph;
197
198
199 /* we compute the blues simply by loading each character from the */
200 /* 'af_latin2_blue_chars[blues]' string, then compute its top-most or */
201 /* bottom-most points (depending on `AF_IS_TOP_BLUE') */
202
203 FT_TRACE5(( "blue zones computation\n"
204 "======================\n\n" ));
205
206 for ( bb = 0; bb < AF_LATIN_BLUE_MAX; bb++ )
207 {
208 const char* p = af_latin2_blue_chars[bb];
209 const char* limit = p + AF_LATIN_MAX_TEST_CHARACTERS;
210 FT_Pos* blue_ref;
211 FT_Pos* blue_shoot;
212
213
214 FT_TRACE5(( "blue zone %d:\n", bb ));
215
216 num_flats = 0;
217 num_rounds = 0;
218
219 for ( ; p < limit && *p; p++ )
220 {
221 FT_UInt glyph_index;
222 FT_Int best_point, best_y, best_first, best_last;
223 FT_Vector* points;
224 FT_Bool round;
225
226
227 /* load the character in the face -- skip unknown or empty ones */
228 glyph_index = FT_Get_Char_Index( face, (FT_UInt)*p );
229 if ( glyph_index == 0 )
230 continue;
231
232 error = FT_Load_Glyph( face, glyph_index, FT_LOAD_NO_SCALE );
233 if ( error || glyph->outline.n_points <= 0 )
234 continue;
235
236 /* now compute min or max point indices and coordinates */
237 points = glyph->outline.points;
238 best_point = -1;
239 best_y = 0; /* make compiler happy */
240 best_first = 0; /* ditto */
241 best_last = 0; /* ditto */
242
243 {
244 FT_Int nn;
245 FT_Int first = 0;
246 FT_Int last = -1;
247
248
249 for ( nn = 0; nn < glyph->outline.n_contours; first = last+1, nn++ )
250 {
251 FT_Int old_best_point = best_point;
252 FT_Int pp;
253
254
255 last = glyph->outline.contours[nn];
256
257 /* Avoid single-point contours since they are never rasterized. */
258 /* In some fonts, they correspond to mark attachment points */
259 /* which are way outside of the glyph's real outline. */
260 if ( last == first )
261 continue;
262
263 if ( AF_LATIN_IS_TOP_BLUE( bb ) )
264 {
265 for ( pp = first; pp <= last; pp++ )
266 if ( best_point < 0 || points[pp].y > best_y )
267 {
268 best_point = pp;
269 best_y = points[pp].y;
270 }
271 }
272 else
273 {
274 for ( pp = first; pp <= last; pp++ )
275 if ( best_point < 0 || points[pp].y < best_y )
276 {
277 best_point = pp;
278 best_y = points[pp].y;
279 }
280 }
281
282 if ( best_point != old_best_point )
283 {
284 best_first = first;
285 best_last = last;
286 }
287 }
288 FT_TRACE5(( " %c %d", *p, best_y ));
289 }
290
291 /* now check whether the point belongs to a straight or round */
292 /* segment; we first need to find in which contour the extremum */
293 /* lies, then inspect its previous and next points */
294 {
295 FT_Pos best_x = points[best_point].x;
296 FT_Int start, end, prev, next;
297 FT_Pos dist;
298
299
300 /* now look for the previous and next points that are not on the */
301 /* same Y coordinate. Threshold the `closeness'... */
302 start = end = best_point;
303
304 do
305 {
306 prev = start - 1;
307 if ( prev < best_first )
308 prev = best_last;
309
310 dist = FT_ABS( points[prev].y - best_y );
311 /* accept a small distance or a small angle (both values are */
312 /* heuristic; value 20 corresponds to approx. 2.9 degrees) */
313 if ( dist > 5 )
314 if ( FT_ABS( points[prev].x - best_x ) <= 20 * dist )
315 break;
316
317 start = prev;
318
319 } while ( start != best_point );
320
321 do
322 {
323 next = end + 1;
324 if ( next > best_last )
325 next = best_first;
326
327 dist = FT_ABS( points[next].y - best_y );
328 if ( dist > 5 )
329 if ( FT_ABS( points[next].x - best_x ) <= 20 * dist )
330 break;
331
332 end = next;
333
334 } while ( end != best_point );
335
336 /* now, set the `round' flag depending on the segment's kind */
337 round = FT_BOOL(
338 FT_CURVE_TAG( glyph->outline.tags[start] ) != FT_CURVE_TAG_ON ||
339 FT_CURVE_TAG( glyph->outline.tags[ end ] ) != FT_CURVE_TAG_ON );
340
341 FT_TRACE5(( " (%s)\n", round ? "round" : "flat" ));
342 }
343
344 if ( round )
345 rounds[num_rounds++] = best_y;
346 else
347 flats[num_flats++] = best_y;
348 }
349
350 if ( num_flats == 0 && num_rounds == 0 )
351 {
352 /*
353 * we couldn't find a single glyph to compute this blue zone,
354 * we will simply ignore it then
355 */
356 FT_TRACE5(( " empty\n" ));
357 continue;
358 }
359
360 /* we have computed the contents of the `rounds' and `flats' tables, */
361 /* now determine the reference and overshoot position of the blue -- */
362 /* we simply take the median value after a simple sort */
363 af_sort_pos( num_rounds, rounds );
364 af_sort_pos( num_flats, flats );
365
366 blue = & axis->blues[axis->blue_count];
367 blue_ref = & blue->ref.org;
368 blue_shoot = & blue->shoot.org;
369
370 axis->blue_count++;
371
372 if ( num_flats == 0 )
373 {
374 *blue_ref =
375 *blue_shoot = rounds[num_rounds / 2];
376 }
377 else if ( num_rounds == 0 )
378 {
379 *blue_ref =
380 *blue_shoot = flats[num_flats / 2];
381 }
382 else
383 {
384 *blue_ref = flats[num_flats / 2];
385 *blue_shoot = rounds[num_rounds / 2];
386 }
387
388 /* there are sometimes problems: if the overshoot position of top */
389 /* zones is under its reference position, or the opposite for bottom */
390 /* zones. We must thus check everything there and correct the errors */
391 if ( *blue_shoot != *blue_ref )
392 {
393 FT_Pos ref = *blue_ref;
394 FT_Pos shoot = *blue_shoot;
395 FT_Bool over_ref = FT_BOOL( shoot > ref );
396
397
398 if ( AF_LATIN_IS_TOP_BLUE( bb ) ^ over_ref )
399 {
400 *blue_ref =
401 *blue_shoot = ( shoot + ref ) / 2;
402
403 FT_TRACE5(( " [overshoot smaller than reference,"
404 " taking mean value]\n" ));
405 }
406 }
407
408 blue->flags = 0;
409 if ( AF_LATIN_IS_TOP_BLUE( bb ) )
410 blue->flags |= AF_LATIN_BLUE_TOP;
411
412 /*
413 * The following flag is used later to adjust the y and x scales
414 * in order to optimize the pixel grid alignment of the top of small
415 * letters.
416 */
417 if ( AF_LATIN_IS_X_HEIGHT_BLUE( bb ) )
418 blue->flags |= AF_LATIN_BLUE_ADJUSTMENT;
419
420 FT_TRACE5(( " -> reference = %ld\n"
421 " overshoot = %ld\n",
422 *blue_ref, *blue_shoot ));
423 }
424
425 return;
426 }
427
428
429 FT_LOCAL_DEF( void )
430 af_latin2_metrics_check_digits( AF_LatinMetrics metrics,
431 FT_Face face )
432 {
433 FT_UInt i;
434 FT_Bool started = 0, same_width = 1;
435 FT_Fixed advance, old_advance = 0;
436
437
438 /* check whether all ASCII digits have the same advance width; */
439 /* digit `0' is 0x30 in all supported charmaps */
440 for ( i = 0x30; i <= 0x39; i++ )
441 {
442 FT_UInt glyph_index;
443
444
445 glyph_index = FT_Get_Char_Index( face, i );
446 if ( glyph_index == 0 )
447 continue;
448
449 if ( FT_Get_Advance( face, glyph_index,
450 FT_LOAD_NO_SCALE |
451 FT_LOAD_NO_HINTING |
452 FT_LOAD_IGNORE_TRANSFORM,
453 &advance ) )
454 continue;
455
456 if ( started )
457 {
458 if ( advance != old_advance )
459 {
460 same_width = 0;
461 break;
462 }
463 }
464 else
465 {
466 old_advance = advance;
467 started = 1;
468 }
469 }
470
471 metrics->root.digits_have_same_width = same_width;
472 }
473
474
475 FT_LOCAL_DEF( FT_Error )
476 af_latin2_metrics_init( AF_LatinMetrics metrics,
477 FT_Face face )
478 {
479 FT_Error error = FT_Err_Ok;
480 FT_CharMap oldmap = face->charmap;
481 FT_UInt ee;
482
483 static const FT_Encoding latin_encodings[] =
484 {
485 FT_ENCODING_UNICODE,
486 FT_ENCODING_APPLE_ROMAN,
487 FT_ENCODING_ADOBE_STANDARD,
488 FT_ENCODING_ADOBE_LATIN_1,
489 FT_ENCODING_NONE /* end of list */
490 };
491
492
493 metrics->units_per_em = face->units_per_EM;
494
495 /* do we have a latin charmap in there? */
496 for ( ee = 0; latin_encodings[ee] != FT_ENCODING_NONE; ee++ )
497 {
498 error = FT_Select_Charmap( face, latin_encodings[ee] );
499 if ( !error )
500 break;
501 }
502
503 if ( !error )
504 {
505 af_latin2_metrics_init_widths( metrics, face );
506 af_latin2_metrics_init_blues( metrics, face );
507 af_latin2_metrics_check_digits( metrics, face );
508 }
509
510 FT_Set_Charmap( face, oldmap );
511 return FT_Err_Ok;
512 }
513
514
515 static void
516 af_latin2_metrics_scale_dim( AF_LatinMetrics metrics,
517 AF_Scaler scaler,
518 AF_Dimension dim )
519 {
520 FT_Fixed scale;
521 FT_Pos delta;
522 AF_LatinAxis axis;
523 FT_UInt nn;
524
525
526 if ( dim == AF_DIMENSION_HORZ )
527 {
528 scale = scaler->x_scale;
529 delta = scaler->x_delta;
530 }
531 else
532 {
533 scale = scaler->y_scale;
534 delta = scaler->y_delta;
535 }
536
537 axis = &metrics->axis[dim];
538
539 if ( axis->org_scale == scale && axis->org_delta == delta )
540 return;
541
542 axis->org_scale = scale;
543 axis->org_delta = delta;
544
545 /*
546 * correct Y scale to optimize the alignment of the top of small
547 * letters to the pixel grid
548 */
549 if ( dim == AF_DIMENSION_VERT )
550 {
551 AF_LatinAxis vaxis = &metrics->axis[AF_DIMENSION_VERT];
552 AF_LatinBlue blue = NULL;
553
554
555 for ( nn = 0; nn < vaxis->blue_count; nn++ )
556 {
557 if ( vaxis->blues[nn].flags & AF_LATIN_BLUE_ADJUSTMENT )
558 {
559 blue = &vaxis->blues[nn];
560 break;
561 }
562 }
563
564 if ( blue )
565 {
566 FT_Pos scaled;
567 FT_Pos threshold;
568 FT_Pos fitted;
569 FT_UInt limit;
570 FT_UInt ppem;
571
572
573 scaled = FT_MulFix( blue->shoot.org, scaler->y_scale );
574 ppem = metrics->root.scaler.face->size->metrics.x_ppem;
575 limit = metrics->root.globals->increase_x_height;
576 threshold = 40;
577
578 /* if the `increase-x-height' property is active, */
579 /* we round up much more often */
580 if ( limit &&
581 ppem <= limit &&
582 ppem >= AF_PROP_INCREASE_X_HEIGHT_MIN )
583 threshold = 52;
584
585 fitted = ( scaled + threshold ) & ~63;
586
587 #if 1
588 if ( scaled != fitted )
589 {
590 scale = FT_MulDiv( scale, fitted, scaled );
591 FT_TRACE5(( "== scaled x-top = %.2g"
592 " fitted = %.2g, scaling = %.4g\n",
593 scaled / 64.0, fitted / 64.0,
594 ( fitted * 1.0 ) / scaled ));
595 }
596 #endif
597 }
598 }
599
600 axis->scale = scale;
601 axis->delta = delta;
602
603 if ( dim == AF_DIMENSION_HORZ )
604 {
605 metrics->root.scaler.x_scale = scale;
606 metrics->root.scaler.x_delta = delta;
607 }
608 else
609 {
610 metrics->root.scaler.y_scale = scale;
611 metrics->root.scaler.y_delta = delta;
612 }
613
614 /* scale the standard widths */
615 for ( nn = 0; nn < axis->width_count; nn++ )
616 {
617 AF_Width width = axis->widths + nn;
618
619
620 width->cur = FT_MulFix( width->org, scale );
621 width->fit = width->cur;
622 }
623
624 /* an extra-light axis corresponds to a standard width that is */
625 /* smaller than 5/8 pixels */
626 axis->extra_light =
627 (FT_Bool)( FT_MulFix( axis->standard_width, scale ) < 32 + 8 );
628
629 if ( dim == AF_DIMENSION_VERT )
630 {
631 /* scale the blue zones */
632 for ( nn = 0; nn < axis->blue_count; nn++ )
633 {
634 AF_LatinBlue blue = &axis->blues[nn];
635 FT_Pos dist;
636
637
638 blue->ref.cur = FT_MulFix( blue->ref.org, scale ) + delta;
639 blue->ref.fit = blue->ref.cur;
640 blue->shoot.cur = FT_MulFix( blue->shoot.org, scale ) + delta;
641 blue->shoot.fit = blue->shoot.cur;
642 blue->flags &= ~AF_LATIN_BLUE_ACTIVE;
643
644 /* a blue zone is only active if it is less than 3/4 pixels tall */
645 dist = FT_MulFix( blue->ref.org - blue->shoot.org, scale );
646 if ( dist <= 48 && dist >= -48 )
647 {
648 FT_Pos delta1, delta2;
649
650 delta1 = blue->shoot.org - blue->ref.org;
651 delta2 = delta1;
652 if ( delta1 < 0 )
653 delta2 = -delta2;
654
655 delta2 = FT_MulFix( delta2, scale );
656
657 if ( delta2 < 32 )
658 delta2 = 0;
659 else if ( delta2 < 64 )
660 delta2 = 32 + ( ( ( delta2 - 32 ) + 16 ) & ~31 );
661 else
662 delta2 = FT_PIX_ROUND( delta2 );
663
664 if ( delta1 < 0 )
665 delta2 = -delta2;
666
667 blue->ref.fit = FT_PIX_ROUND( blue->ref.cur );
668 blue->shoot.fit = blue->ref.fit + delta2;
669
670 FT_TRACE5(( ">> activating blue zone %d:"
671 " ref.cur=%.2g ref.fit=%.2g"
672 " shoot.cur=%.2g shoot.fit=%.2g\n",
673 nn, blue->ref.cur / 64.0, blue->ref.fit / 64.0,
674 blue->shoot.cur / 64.0, blue->shoot.fit / 64.0 ));
675
676 blue->flags |= AF_LATIN_BLUE_ACTIVE;
677 }
678 }
679 }
680 }
681
682
683 FT_LOCAL_DEF( void )
684 af_latin2_metrics_scale( AF_LatinMetrics metrics,
685 AF_Scaler scaler )
686 {
687 metrics->root.scaler.render_mode = scaler->render_mode;
688 metrics->root.scaler.face = scaler->face;
689 metrics->root.scaler.flags = scaler->flags;
690
691 af_latin2_metrics_scale_dim( metrics, scaler, AF_DIMENSION_HORZ );
692 af_latin2_metrics_scale_dim( metrics, scaler, AF_DIMENSION_VERT );
693 }
694
695
696 /* Extract standard_width from writing system/script specific */
697 /* metrics class. */
698
699 FT_LOCAL_DEF( void )
700 af_latin2_get_standard_widths( AF_LatinMetrics metrics,
701 FT_Pos* stdHW,
702 FT_Pos* stdVW )
703 {
704 if ( stdHW )
705 *stdHW = metrics->axis[AF_DIMENSION_VERT].standard_width;
706
707 if ( stdVW )
708 *stdVW = metrics->axis[AF_DIMENSION_HORZ].standard_width;
709 }
710
711
712 /*************************************************************************/
713 /*************************************************************************/
714 /***** *****/
715 /***** L A T I N G L Y P H A N A L Y S I S *****/
716 /***** *****/
717 /*************************************************************************/
718 /*************************************************************************/
719
720 #define SORT_SEGMENTS
721
722 FT_LOCAL_DEF( FT_Error )
723 af_latin2_hints_compute_segments( AF_GlyphHints hints,
724 AF_Dimension dim )
725 {
726 AF_AxisHints axis = &hints->axis[dim];
727 FT_Memory memory = hints->memory;
728 FT_Error error = FT_Err_Ok;
729 AF_Segment segment = NULL;
730 AF_SegmentRec seg0;
731 AF_Point* contour = hints->contours;
732 AF_Point* contour_limit = contour + hints->num_contours;
733 AF_Direction major_dir, segment_dir;
734
735
736 FT_ZERO( &seg0 );
737 seg0.score = 32000;
738 seg0.flags = AF_EDGE_NORMAL;
739
740 major_dir = (AF_Direction)FT_ABS( axis->major_dir );
741 segment_dir = major_dir;
742
743 axis->num_segments = 0;
744
745 /* set up (u,v) in each point */
746 if ( dim == AF_DIMENSION_HORZ )
747 {
748 AF_Point point = hints->points;
749 AF_Point limit = point + hints->num_points;
750
751
752 for ( ; point < limit; point++ )
753 {
754 point->u = point->fx;
755 point->v = point->fy;
756 }
757 }
758 else
759 {
760 AF_Point point = hints->points;
761 AF_Point limit = point + hints->num_points;
762
763
764 for ( ; point < limit; point++ )
765 {
766 point->u = point->fy;
767 point->v = point->fx;
768 }
769 }
770
771 /* do each contour separately */
772 for ( ; contour < contour_limit; contour++ )
773 {
774 AF_Point point = contour[0];
775 AF_Point start = point;
776 AF_Point last = point->prev;
777
778
779 if ( point == last ) /* skip singletons -- just in case */
780 continue;
781
782 /* already on an edge ?, backtrack to find its start */
783 if ( FT_ABS( point->in_dir ) == major_dir )
784 {
785 point = point->prev;
786
787 while ( point->in_dir == start->in_dir )
788 point = point->prev;
789 }
790 else /* otherwise, find first segment start, if any */
791 {
792 while ( FT_ABS( point->out_dir ) != major_dir )
793 {
794 point = point->next;
795
796 if ( point == start )
797 goto NextContour;
798 }
799 }
800
801 start = point;
802
803 for (;;)
804 {
805 AF_Point first;
806 FT_Pos min_u, min_v, max_u, max_v;
807
808 /* we're at the start of a new segment */
809 FT_ASSERT( FT_ABS( point->out_dir ) == major_dir &&
810 point->in_dir != point->out_dir );
811 first = point;
812
813 min_u = max_u = point->u;
814 min_v = max_v = point->v;
815
816 point = point->next;
817
818 while ( point->out_dir == first->out_dir )
819 {
820 point = point->next;
821
822 if ( point->u < min_u )
823 min_u = point->u;
824
825 if ( point->u > max_u )
826 max_u = point->u;
827 }
828
829 if ( point->v < min_v )
830 min_v = point->v;
831
832 if ( point->v > max_v )
833 max_v = point->v;
834
835 /* record new segment */
836 error = af_axis_hints_new_segment( axis, memory, &segment );
837 if ( error )
838 goto Exit;
839
840 segment[0] = seg0;
841 segment->dir = first->out_dir;
842 segment->first = first;
843 segment->last = point;
844 segment->pos = (FT_Short)( ( min_u + max_u ) >> 1 );
845 segment->min_coord = (FT_Short) min_v;
846 segment->max_coord = (FT_Short) max_v;
847 segment->height = (FT_Short)( max_v - min_v );
848
849 /* a segment is round if it doesn't have successive */
850 /* on-curve points. */
851 {
852 AF_Point pt = first;
853 AF_Point last = point;
854 FT_UInt f0 = pt->flags & AF_FLAG_CONTROL;
855 FT_UInt f1;
856
857
858 segment->flags &= ~AF_EDGE_ROUND;
859
860 for ( ; pt != last; f0 = f1 )
861 {
862 pt = pt->next;
863 f1 = pt->flags & AF_FLAG_CONTROL;
864
865 if ( !f0 && !f1 )
866 break;
867
868 if ( pt == last )
869 segment->flags |= AF_EDGE_ROUND;
870 }
871 }
872
873 /* this can happen in the case of a degenerate contour
874 * e.g. a 2-point vertical contour
875 */
876 if ( point == start )
877 break;
878
879 /* jump to the start of the next segment, if any */
880 while ( FT_ABS( point->out_dir ) != major_dir )
881 {
882 point = point->next;
883
884 if ( point == start )
885 goto NextContour;
886 }
887 }
888
889 NextContour:
890 ;
891 } /* contours */
892
893 /* now slightly increase the height of segments when this makes */
894 /* sense -- this is used to better detect and ignore serifs */
895 {
896 AF_Segment segments = axis->segments;
897 AF_Segment segments_end = segments + axis->num_segments;
898
899
900 for ( segment = segments; segment < segments_end; segment++ )
901 {
902 AF_Point first = segment->first;
903 AF_Point last = segment->last;
904 AF_Point p;
905 FT_Pos first_v = first->v;
906 FT_Pos last_v = last->v;
907
908
909 if ( first_v < last_v )
910 {
911 p = first->prev;
912 if ( p->v < first_v )
913 segment->height = (FT_Short)( segment->height +
914 ( ( first_v - p->v ) >> 1 ) );
915
916 p = last->next;
917 if ( p->v > last_v )
918 segment->height = (FT_Short)( segment->height +
919 ( ( p->v - last_v ) >> 1 ) );
920 }
921 else
922 {
923 p = first->prev;
924 if ( p->v > first_v )
925 segment->height = (FT_Short)( segment->height +
926 ( ( p->v - first_v ) >> 1 ) );
927
928 p = last->next;
929 if ( p->v < last_v )
930 segment->height = (FT_Short)( segment->height +
931 ( ( last_v - p->v ) >> 1 ) );
932 }
933 }
934 }
935
936 #ifdef AF_SORT_SEGMENTS
937 /* place all segments with a negative direction to the start
938 * of the array, used to speed up segment linking later...
939 */
940 {
941 AF_Segment segments = axis->segments;
942 FT_UInt count = axis->num_segments;
943 FT_UInt ii, jj;
944
945 for ( ii = 0; ii < count; ii++ )
946 {
947 if ( segments[ii].dir > 0 )
948 {
949 for ( jj = ii + 1; jj < count; jj++ )
950 {
951 if ( segments[jj].dir < 0 )
952 {
953 AF_SegmentRec tmp;
954
955
956 tmp = segments[ii];
957 segments[ii] = segments[jj];
958 segments[jj] = tmp;
959
960 break;
961 }
962 }
963
964 if ( jj == count )
965 break;
966 }
967 }
968 axis->mid_segments = ii;
969 }
970 #endif
971
972 Exit:
973 return error;
974 }
975
976
977 FT_LOCAL_DEF( void )
978 af_latin2_hints_link_segments( AF_GlyphHints hints,
979 AF_Dimension dim )
980 {
981 AF_AxisHints axis = &hints->axis[dim];
982 AF_Segment segments = axis->segments;
983 AF_Segment segment_limit = segments + axis->num_segments;
984 #ifdef AF_SORT_SEGMENTS
985 AF_Segment segment_mid = segments + axis->mid_segments;
986 #endif
987 FT_Pos len_threshold, len_score;
988 AF_Segment seg1, seg2;
989
990
991 len_threshold = AF_LATIN_CONSTANT( hints->metrics, 8 );
992 if ( len_threshold == 0 )
993 len_threshold = 1;
994
995 len_score = AF_LATIN_CONSTANT( hints->metrics, 6000 );
996
997 #ifdef AF_SORT_SEGMENTS
998 for ( seg1 = segments; seg1 < segment_mid; seg1++ )
999 {
1000 if ( seg1->dir != axis->major_dir )
1001 continue;
1002
1003 for ( seg2 = segment_mid; seg2 < segment_limit; seg2++ )
1004 #else
1005 /* now compare each segment to the others */
1006 for ( seg1 = segments; seg1 < segment_limit; seg1++ )
1007 {
1008 if ( seg1->dir != axis->major_dir )
1009 continue;
1010
1011 for ( seg2 = segments; seg2 < segment_limit; seg2++ )
1012 if ( seg1->dir + seg2->dir == 0 && seg2->pos > seg1->pos )
1013 #endif
1014 {
1015 FT_Pos pos1 = seg1->pos;
1016 FT_Pos pos2 = seg2->pos;
1017 FT_Pos dist = pos2 - pos1;
1018
1019
1020 if ( dist < 0 )
1021 continue;
1022
1023 {
1024 FT_Pos min = seg1->min_coord;
1025 FT_Pos max = seg1->max_coord;
1026 FT_Pos len, score;
1027
1028
1029 if ( min < seg2->min_coord )
1030 min = seg2->min_coord;
1031
1032 if ( max > seg2->max_coord )
1033 max = seg2->max_coord;
1034
1035 len = max - min;
1036 if ( len >= len_threshold )
1037 {
1038 score = dist + len_score / len;
1039 if ( score < seg1->score )
1040 {
1041 seg1->score = score;
1042 seg1->link = seg2;
1043 }
1044
1045 if ( score < seg2->score )
1046 {
1047 seg2->score = score;
1048 seg2->link = seg1;
1049 }
1050 }
1051 }
1052 }
1053 }
1054 #if 0
1055 }
1056 #endif
1057
1058 /* now, compute the `serif' segments */
1059 for ( seg1 = segments; seg1 < segment_limit; seg1++ )
1060 {
1061 seg2 = seg1->link;
1062
1063 if ( seg2 )
1064 {
1065 if ( seg2->link != seg1 )
1066 {
1067 seg1->link = NULL;
1068 seg1->serif = seg2->link;
1069 }
1070 }
1071 }
1072 }
1073
1074
1075 FT_LOCAL_DEF( FT_Error )
1076 af_latin2_hints_compute_edges( AF_GlyphHints hints,
1077 AF_Dimension dim )
1078 {
1079 AF_AxisHints axis = &hints->axis[dim];
1080 FT_Error error = FT_Err_Ok;
1081 FT_Memory memory = hints->memory;
1082 AF_LatinAxis laxis = &((AF_LatinMetrics)hints->metrics)->axis[dim];
1083
1084 AF_Segment segments = axis->segments;
1085 AF_Segment segment_limit = segments + axis->num_segments;
1086 AF_Segment seg;
1087
1088 AF_Direction up_dir;
1089 FT_Fixed scale;
1090 FT_Pos edge_distance_threshold;
1091 FT_Pos segment_length_threshold;
1092
1093
1094 axis->num_edges = 0;
1095
1096 scale = ( dim == AF_DIMENSION_HORZ ) ? hints->x_scale
1097 : hints->y_scale;
1098
1099 up_dir = ( dim == AF_DIMENSION_HORZ ) ? AF_DIR_UP
1100 : AF_DIR_RIGHT;
1101
1102 /*
1103 * We want to ignore very small (mostly serif) segments, we do that
1104 * by ignoring those that whose length is less than a given fraction
1105 * of the standard width. If there is no standard width, we ignore
1106 * those that are less than a given size in pixels
1107 *
1108 * also, unlink serif segments that are linked to segments farther
1109 * than 50% of the standard width
1110 */
1111 if ( dim == AF_DIMENSION_HORZ )
1112 {
1113 if ( laxis->width_count > 0 )
1114 segment_length_threshold = ( laxis->standard_width * 10 ) >> 4;
1115 else
1116 segment_length_threshold = FT_DivFix( 64, hints->y_scale );
1117 }
1118 else
1119 segment_length_threshold = 0;
1120
1121 /*********************************************************************/
1122 /* */
1123 /* We will begin by generating a sorted table of edges for the */
1124 /* current direction. To do so, we simply scan each segment and try */
1125 /* to find an edge in our table that corresponds to its position. */
1126 /* */
1127 /* If no edge is found, we create and insert a new edge in the */
1128 /* sorted table. Otherwise, we simply add the segment to the edge's */
1129 /* list which will be processed in the second step to compute the */
1130 /* edge's properties. */
1131 /* */
1132 /* Note that the edges table is sorted along the segment/edge */
1133 /* position. */
1134 /* */
1135 /*********************************************************************/
1136
1137 edge_distance_threshold = FT_MulFix( laxis->edge_distance_threshold,
1138 scale );
1139 if ( edge_distance_threshold > 64 / 4 )
1140 edge_distance_threshold = 64 / 4;
1141
1142 edge_distance_threshold = FT_DivFix( edge_distance_threshold,
1143 scale );
1144
1145 for ( seg = segments; seg < segment_limit; seg++ )
1146 {
1147 AF_Edge found = NULL;
1148 FT_Int ee;
1149
1150
1151 if ( seg->height < segment_length_threshold )
1152 continue;
1153
1154 /* A special case for serif edges: If they are smaller than */
1155 /* 1.5 pixels we ignore them. */
1156 if ( seg->serif )
1157 {
1158 FT_Pos dist = seg->serif->pos - seg->pos;
1159
1160
1161 if ( dist < 0 )
1162 dist = -dist;
1163
1164 if ( dist >= laxis->standard_width >> 1 )
1165 {
1166 /* unlink this serif, it is too distant from its reference stem */
1167 seg->serif = NULL;
1168 }
1169 else if ( 2*seg->height < 3 * segment_length_threshold )
1170 continue;
1171 }
1172
1173 /* look for an edge corresponding to the segment */
1174 for ( ee = 0; ee < axis->num_edges; ee++ )
1175 {
1176 AF_Edge edge = axis->edges + ee;
1177 FT_Pos dist;
1178
1179
1180 dist = seg->pos - edge->fpos;
1181 if ( dist < 0 )
1182 dist = -dist;
1183
1184 if ( dist < edge_distance_threshold && edge->dir == seg->dir )
1185 {
1186 found = edge;
1187 break;
1188 }
1189 }
1190
1191 if ( !found )
1192 {
1193 AF_Edge edge;
1194
1195
1196 /* insert a new edge in the list and */
1197 /* sort according to the position */
1198 error = af_axis_hints_new_edge( axis, seg->pos, seg->dir, 0,
1199 memory, &edge );
1200 if ( error )
1201 goto Exit;
1202
1203 /* add the segment to the new edge's list */
1204 FT_ZERO( edge );
1205
1206 edge->first = seg;
1207 edge->last = seg;
1208 edge->dir = seg->dir;
1209 edge->fpos = seg->pos;
1210 edge->opos = FT_MulFix( seg->pos, scale );
1211 edge->pos = edge->opos;
1212 seg->edge_next = seg;
1213 }
1214 else
1215 {
1216 /* if an edge was found, simply add the segment to the edge's */
1217 /* list */
1218 seg->edge_next = found->first;
1219 found->last->edge_next = seg;
1220 found->last = seg;
1221 }
1222 }
1223
1224
1225 /*********************************************************************/
1226 /* */
1227 /* Good, we will now compute each edge's properties according to */
1228 /* segments found on its position. Basically, these are: */
1229 /* */
1230 /* - edge's main direction */
1231 /* - stem edge, serif edge or both (which defaults to stem then) */
1232 /* - rounded edge, straight or both (which defaults to straight) */
1233 /* - link for edge */
1234 /* */
1235 /*********************************************************************/
1236
1237 /* first of all, set the `edge' field in each segment -- this is */
1238 /* required in order to compute edge links */
1239
1240 /*
1241 * Note that removing this loop and setting the `edge' field of each
1242 * segment directly in the code above slows down execution speed for
1243 * some reasons on platforms like the Sun.
1244 */
1245 {
1246 AF_Edge edges = axis->edges;
1247 AF_Edge edge_limit = edges + axis->num_edges;
1248 AF_Edge edge;
1249
1250
1251 for ( edge = edges; edge < edge_limit; edge++ )
1252 {
1253 seg = edge->first;
1254 if ( seg )
1255 do
1256 {
1257 seg->edge = edge;
1258 seg = seg->edge_next;
1259
1260 } while ( seg != edge->first );
1261 }
1262
1263 /* now, compute each edge properties */
1264 for ( edge = edges; edge < edge_limit; edge++ )
1265 {
1266 FT_Int is_round = 0; /* does it contain round segments? */
1267 FT_Int is_straight = 0; /* does it contain straight segments? */
1268 #if 0
1269 FT_Pos ups = 0; /* number of upwards segments */
1270 FT_Pos downs = 0; /* number of downwards segments */
1271 #endif
1272
1273
1274 seg = edge->first;
1275
1276 do
1277 {
1278 FT_Bool is_serif;
1279
1280
1281 /* check for roundness of segment */
1282 if ( seg->flags & AF_EDGE_ROUND )
1283 is_round++;
1284 else
1285 is_straight++;
1286
1287 #if 0
1288 /* check for segment direction */
1289 if ( seg->dir == up_dir )
1290 ups += seg->max_coord-seg->min_coord;
1291 else
1292 downs += seg->max_coord-seg->min_coord;
1293 #endif
1294
1295 /* check for links -- if seg->serif is set, then seg->link must */
1296 /* be ignored */
1297 is_serif = (FT_Bool)( seg->serif &&
1298 seg->serif->edge &&
1299 seg->serif->edge != edge );
1300
1301 if ( ( seg->link && seg->link->edge != NULL ) || is_serif )
1302 {
1303 AF_Edge edge2;
1304 AF_Segment seg2;
1305
1306
1307 edge2 = edge->link;
1308 seg2 = seg->link;
1309
1310 if ( is_serif )
1311 {
1312 seg2 = seg->serif;
1313 edge2 = edge->serif;
1314 }
1315
1316 if ( edge2 )
1317 {
1318 FT_Pos edge_delta;
1319 FT_Pos seg_delta;
1320
1321
1322 edge_delta = edge->fpos - edge2->fpos;
1323 if ( edge_delta < 0 )
1324 edge_delta = -edge_delta;
1325
1326 seg_delta = seg->pos - seg2->pos;
1327 if ( seg_delta < 0 )
1328 seg_delta = -seg_delta;
1329
1330 if ( seg_delta < edge_delta )
1331 edge2 = seg2->edge;
1332 }
1333 else
1334 edge2 = seg2->edge;
1335
1336 if ( is_serif )
1337 {
1338 edge->serif = edge2;
1339 edge2->flags |= AF_EDGE_SERIF;
1340 }
1341 else
1342 edge->link = edge2;
1343 }
1344
1345 seg = seg->edge_next;
1346
1347 } while ( seg != edge->first );
1348
1349 /* set the round/straight flags */
1350 edge->flags = AF_EDGE_NORMAL;
1351
1352 if ( is_round > 0 && is_round >= is_straight )
1353 edge->flags |= AF_EDGE_ROUND;
1354
1355 #if 0
1356 /* set the edge's main direction */
1357 edge->dir = AF_DIR_NONE;
1358
1359 if ( ups > downs )
1360 edge->dir = (FT_Char)up_dir;
1361
1362 else if ( ups < downs )
1363 edge->dir = (FT_Char)-up_dir;
1364
1365 else if ( ups == downs )
1366 edge->dir = 0; /* both up and down! */
1367 #endif
1368
1369 /* gets rid of serifs if link is set */
1370 /* XXX: This gets rid of many unpleasant artefacts! */
1371 /* Example: the `c' in cour.pfa at size 13 */
1372
1373 if ( edge->serif && edge->link )
1374 edge->serif = NULL;
1375 }
1376 }
1377
1378 Exit:
1379 return error;
1380 }
1381
1382
1383 FT_LOCAL_DEF( FT_Error )
1384 af_latin2_hints_detect_features( AF_GlyphHints hints,
1385 AF_Dimension dim )
1386 {
1387 FT_Error error;
1388
1389
1390 error = af_latin2_hints_compute_segments( hints, dim );
1391 if ( !error )
1392 {
1393 af_latin2_hints_link_segments( hints, dim );
1394
1395 error = af_latin2_hints_compute_edges( hints, dim );
1396 }
1397 return error;
1398 }
1399
1400
1401 static void
1402 af_latin2_hints_compute_blue_edges( AF_GlyphHints hints,
1403 AF_LatinMetrics metrics )
1404 {
1405 AF_AxisHints axis = &hints->axis[AF_DIMENSION_VERT];
1406 AF_Edge edge = axis->edges;
1407 AF_Edge edge_limit = edge + axis->num_edges;
1408 AF_LatinAxis latin = &metrics->axis[AF_DIMENSION_VERT];
1409 FT_Fixed scale = latin->scale;
1410 FT_Pos best_dist0; /* initial threshold */
1411
1412
1413 /* compute the initial threshold as a fraction of the EM size */
1414 best_dist0 = FT_MulFix( metrics->units_per_em / 40, scale );
1415
1416 if ( best_dist0 > 64 / 2 )
1417 best_dist0 = 64 / 2;
1418
1419 /* compute which blue zones are active, i.e. have their scaled */
1420 /* size < 3/4 pixels */
1421
1422 /* for each horizontal edge search the blue zone which is closest */
1423 for ( ; edge < edge_limit; edge++ )
1424 {
1425 FT_Int bb;
1426 AF_Width best_blue = NULL;
1427 FT_Pos best_dist = best_dist0;
1428
1429 for ( bb = 0; bb < AF_LATIN_BLUE_MAX; bb++ )
1430 {
1431 AF_LatinBlue blue = latin->blues + bb;
1432 FT_Bool is_top_blue, is_major_dir;
1433
1434
1435 /* skip inactive blue zones (i.e., those that are too small) */
1436 if ( !( blue->flags & AF_LATIN_BLUE_ACTIVE ) )
1437 continue;
1438
1439 /* if it is a top zone, check for right edges -- if it is a bottom */
1440 /* zone, check for left edges */
1441 /* */
1442 /* of course, that's for TrueType */
1443 is_top_blue = (FT_Byte)( ( blue->flags & AF_LATIN_BLUE_TOP ) != 0 );
1444 is_major_dir = FT_BOOL( edge->dir == axis->major_dir );
1445
1446 /* if it is a top zone, the edge must be against the major */
1447 /* direction; if it is a bottom zone, it must be in the major */
1448 /* direction */
1449 if ( is_top_blue ^ is_major_dir )
1450 {
1451 FT_Pos dist;
1452 AF_Width compare;
1453
1454
1455 /* if it's a rounded edge, compare it to the overshoot position */
1456 /* if it's a flat edge, compare it to the reference position */
1457 if ( edge->flags & AF_EDGE_ROUND )
1458 compare = &blue->shoot;
1459 else
1460 compare = &blue->ref;
1461
1462 dist = edge->fpos - compare->org;
1463 if ( dist < 0 )
1464 dist = -dist;
1465
1466 dist = FT_MulFix( dist, scale );
1467 if ( dist < best_dist )
1468 {
1469 best_dist = dist;
1470 best_blue = compare;
1471 }
1472
1473 #if 0
1474 /* now, compare it to the overshoot position if the edge is */
1475 /* rounded, and if the edge is over the reference position of a */
1476 /* top zone, or under the reference position of a bottom zone */
1477 if ( edge->flags & AF_EDGE_ROUND && dist != 0 )
1478 {
1479 FT_Bool is_under_ref = FT_BOOL( edge->fpos < blue->ref.org );
1480
1481
1482 if ( is_top_blue ^ is_under_ref )
1483 {
1484 blue = latin->blues + bb;
1485 dist = edge->fpos - blue->shoot.org;
1486 if ( dist < 0 )
1487 dist = -dist;
1488
1489 dist = FT_MulFix( dist, scale );
1490 if ( dist < best_dist )
1491 {
1492 best_dist = dist;
1493 best_blue = & blue->shoot;
1494 }
1495 }
1496 }
1497 #endif
1498 }
1499 }
1500
1501 if ( best_blue )
1502 edge->blue_edge = best_blue;
1503 }
1504 }
1505
1506
1507 static FT_Error
1508 af_latin2_hints_init( AF_GlyphHints hints,
1509 AF_LatinMetrics metrics )
1510 {
1511 FT_Render_Mode mode;
1512 FT_UInt32 scaler_flags, other_flags;
1513 FT_Face face = metrics->root.scaler.face;
1514
1515
1516 af_glyph_hints_rescale( hints, (AF_StyleMetrics)metrics );
1517
1518 /*
1519 * correct x_scale and y_scale if needed, since they may have
1520 * been modified `af_latin2_metrics_scale_dim' above
1521 */
1522 hints->x_scale = metrics->axis[AF_DIMENSION_HORZ].scale;
1523 hints->x_delta = metrics->axis[AF_DIMENSION_HORZ].delta;
1524 hints->y_scale = metrics->axis[AF_DIMENSION_VERT].scale;
1525 hints->y_delta = metrics->axis[AF_DIMENSION_VERT].delta;
1526
1527 /* compute flags depending on render mode, etc. */
1528 mode = metrics->root.scaler.render_mode;
1529
1530 #if 0 /* #ifdef AF_CONFIG_OPTION_USE_WARPER */
1531 if ( mode == FT_RENDER_MODE_LCD || mode == FT_RENDER_MODE_LCD_V )
1532 metrics->root.scaler.render_mode = mode = FT_RENDER_MODE_NORMAL;
1533 #endif
1534
1535 scaler_flags = hints->scaler_flags;
1536 other_flags = 0;
1537
1538 /*
1539 * We snap the width of vertical stems for the monochrome and
1540 * horizontal LCD rendering targets only.
1541 */
1542 if ( mode == FT_RENDER_MODE_MONO || mode == FT_RENDER_MODE_LCD )
1543 other_flags |= AF_LATIN_HINTS_HORZ_SNAP;
1544
1545 /*
1546 * We snap the width of horizontal stems for the monochrome and
1547 * vertical LCD rendering targets only.
1548 */
1549 if ( mode == FT_RENDER_MODE_MONO || mode == FT_RENDER_MODE_LCD_V )
1550 other_flags |= AF_LATIN_HINTS_VERT_SNAP;
1551
1552 /*
1553 * We adjust stems to full pixels only if we don't use the `light' mode.
1554 */
1555 if ( mode != FT_RENDER_MODE_LIGHT )
1556 other_flags |= AF_LATIN_HINTS_STEM_ADJUST;
1557
1558 if ( mode == FT_RENDER_MODE_MONO )
1559 other_flags |= AF_LATIN_HINTS_MONO;
1560
1561 /*
1562 * In `light' hinting mode we disable horizontal hinting completely.
1563 * We also do it if the face is italic.
1564 */
1565 if ( mode == FT_RENDER_MODE_LIGHT ||
1566 ( face->style_flags & FT_STYLE_FLAG_ITALIC ) != 0 )
1567 scaler_flags |= AF_SCALER_FLAG_NO_HORIZONTAL;
1568
1569 #ifdef AF_CONFIG_OPTION_USE_WARPER
1570 /* get (global) warper flag */
1571 if ( !metrics->root.globals->module->warping )
1572 scaler_flags |= AF_SCALER_FLAG_NO_WARPER;
1573 #endif
1574
1575 hints->scaler_flags = scaler_flags;
1576 hints->other_flags = other_flags;
1577
1578 return 0;
1579 }
1580
1581
1582 /*************************************************************************/
1583 /*************************************************************************/
1584 /***** *****/
1585 /***** L A T I N G L Y P H G R I D - F I T T I N G *****/
1586 /***** *****/
1587 /*************************************************************************/
1588 /*************************************************************************/
1589
1590 /* snap a given width in scaled coordinates to one of the */
1591 /* current standard widths */
1592
1593 static FT_Pos
1594 af_latin2_snap_width( AF_Width widths,
1595 FT_UInt count,
1596 FT_Pos width )
1597 {
1598 FT_UInt n;
1599 FT_Pos best = 64 + 32 + 2;
1600 FT_Pos reference = width;
1601 FT_Pos scaled;
1602
1603
1604 for ( n = 0; n < count; n++ )
1605 {
1606 FT_Pos w;
1607 FT_Pos dist;
1608
1609
1610 w = widths[n].cur;
1611 dist = width - w;
1612 if ( dist < 0 )
1613 dist = -dist;
1614 if ( dist < best )
1615 {
1616 best = dist;
1617 reference = w;
1618 }
1619 }
1620
1621 scaled = FT_PIX_ROUND( reference );
1622
1623 if ( width >= reference )
1624 {
1625 if ( width < scaled + 48 )
1626 width = reference;
1627 }
1628 else
1629 {
1630 if ( width > scaled - 48 )
1631 width = reference;
1632 }
1633
1634 return width;
1635 }
1636
1637
1638 /* compute the snapped width of a given stem */
1639
1640 static FT_Pos
1641 af_latin2_compute_stem_width( AF_GlyphHints hints,
1642 AF_Dimension dim,
1643 FT_Pos width,
1644 FT_UInt base_flags,
1645 FT_UInt stem_flags )
1646 {
1647 AF_LatinMetrics metrics = (AF_LatinMetrics) hints->metrics;
1648 AF_LatinAxis axis = & metrics->axis[dim];
1649 FT_Pos dist = width;
1650 FT_Int sign = 0;
1651 FT_Int vertical = ( dim == AF_DIMENSION_VERT );
1652
1653 FT_UNUSED( base_flags );
1654
1655
1656 if ( !AF_LATIN_HINTS_DO_STEM_ADJUST( hints ) ||
1657 axis->extra_light )
1658 return width;
1659
1660 if ( dist < 0 )
1661 {
1662 dist = -width;
1663 sign = 1;
1664 }
1665
1666 if ( ( vertical && !AF_LATIN_HINTS_DO_VERT_SNAP( hints ) ) ||
1667 ( !vertical && !AF_LATIN_HINTS_DO_HORZ_SNAP( hints ) ) )
1668 {
1669 /* smooth hinting process: very lightly quantize the stem width */
1670
1671 /* leave the widths of serifs alone */
1672
1673 if ( ( stem_flags & AF_EDGE_SERIF ) && vertical && ( dist < 3 * 64 ) )
1674 goto Done_Width;
1675
1676 #if 0
1677 else if ( ( base_flags & AF_EDGE_ROUND ) )
1678 {
1679 if ( dist < 80 )
1680 dist = 64;
1681 }
1682 else if ( dist < 56 )
1683 dist = 56;
1684 #endif
1685 if ( axis->width_count > 0 )
1686 {
1687 FT_Pos delta;
1688
1689
1690 /* compare to standard width */
1691 if ( axis->width_count > 0 )
1692 {
1693 delta = dist - axis->widths[0].cur;
1694
1695 if ( delta < 0 )
1696 delta = -delta;
1697
1698 if ( delta < 40 )
1699 {
1700 dist = axis->widths[0].cur;
1701 if ( dist < 48 )
1702 dist = 48;
1703
1704 goto Done_Width;
1705 }
1706 }
1707
1708 if ( dist < 3 * 64 )
1709 {
1710 delta = dist & 63;
1711 dist &= -64;
1712
1713 if ( delta < 10 )
1714 dist += delta;
1715
1716 else if ( delta < 32 )
1717 dist += 10;
1718
1719 else if ( delta < 54 )
1720 dist += 54;
1721
1722 else
1723 dist += delta;
1724 }
1725 else
1726 dist = ( dist + 32 ) & ~63;
1727 }
1728 }
1729 else
1730 {
1731 /* strong hinting process: snap the stem width to integer pixels */
1732 FT_Pos org_dist = dist;
1733
1734
1735 dist = af_latin2_snap_width( axis->widths, axis->width_count, dist );
1736
1737 if ( vertical )
1738 {
1739 /* in the case of vertical hinting, always round */
1740 /* the stem heights to integer pixels */
1741
1742 if ( dist >= 64 )
1743 dist = ( dist + 16 ) & ~63;
1744 else
1745 dist = 64;
1746 }
1747 else
1748 {
1749 if ( AF_LATIN_HINTS_DO_MONO( hints ) )
1750 {
1751 /* monochrome horizontal hinting: snap widths to integer pixels */
1752 /* with a different threshold */
1753
1754 if ( dist < 64 )
1755 dist = 64;
1756 else
1757 dist = ( dist + 32 ) & ~63;
1758 }
1759 else
1760 {
1761 /* for horizontal anti-aliased hinting, we adopt a more subtle */
1762 /* approach: we strengthen small stems, round stems whose size */
1763 /* is between 1 and 2 pixels to an integer, otherwise nothing */
1764
1765 if ( dist < 48 )
1766 dist = ( dist + 64 ) >> 1;
1767
1768 else if ( dist < 128 )
1769 {
1770 /* We only round to an integer width if the corresponding */
1771 /* distortion is less than 1/4 pixel. Otherwise this */
1772 /* makes everything worse since the diagonals, which are */
1773 /* not hinted, appear a lot bolder or thinner than the */
1774 /* vertical stems. */
1775
1776 FT_Int delta;
1777
1778
1779 dist = ( dist + 22 ) & ~63;
1780 delta = dist - org_dist;
1781 if ( delta < 0 )
1782 delta = -delta;
1783
1784 if ( delta >= 16 )
1785 {
1786 dist = org_dist;
1787 if ( dist < 48 )
1788 dist = ( dist + 64 ) >> 1;
1789 }
1790 }
1791 else
1792 /* round otherwise to prevent color fringes in LCD mode */
1793 dist = ( dist + 32 ) & ~63;
1794 }
1795 }
1796 }
1797
1798 Done_Width:
1799 if ( sign )
1800 dist = -dist;
1801
1802 return dist;
1803 }
1804
1805
1806 /* align one stem edge relative to the previous stem edge */
1807
1808 static void
1809 af_latin2_align_linked_edge( AF_GlyphHints hints,
1810 AF_Dimension dim,
1811 AF_Edge base_edge,
1812 AF_Edge stem_edge )
1813 {
1814 FT_Pos dist = stem_edge->opos - base_edge->opos;
1815
1816 FT_Pos fitted_width = af_latin2_compute_stem_width( hints, dim, dist,
1817 base_edge->flags,
1818 stem_edge->flags );
1819
1820
1821 stem_edge->pos = base_edge->pos + fitted_width;
1822
1823 FT_TRACE5(( "LINK: edge %d (opos=%.2f) linked to (%.2f), "
1824 "dist was %.2f, now %.2f\n",
1825 stem_edge-hints->axis[dim].edges, stem_edge->opos / 64.0,
1826 stem_edge->pos / 64.0, dist / 64.0, fitted_width / 64.0 ));
1827 }
1828
1829
1830 static void
1831 af_latin2_align_serif_edge( AF_GlyphHints hints,
1832 AF_Edge base,
1833 AF_Edge serif )
1834 {
1835 FT_UNUSED( hints );
1836
1837 serif->pos = base->pos + ( serif->opos - base->opos );
1838 }
1839
1840
1841 /*************************************************************************/
1842 /*************************************************************************/
1843 /*************************************************************************/
1844 /**** ****/
1845 /**** E D G E H I N T I N G ****/
1846 /**** ****/
1847 /*************************************************************************/
1848 /*************************************************************************/
1849 /*************************************************************************/
1850
1851
1852 static void
1853 af_latin2_hint_edges( AF_GlyphHints hints,
1854 AF_Dimension dim )
1855 {
1856 AF_AxisHints axis = &hints->axis[dim];
1857 AF_Edge edges = axis->edges;
1858 AF_Edge edge_limit = edges + axis->num_edges;
1859 AF_Edge edge;
1860 AF_Edge anchor = NULL;
1861 FT_Int has_serifs = 0;
1862 FT_Pos anchor_drift = 0;
1863
1864
1865
1866 FT_TRACE5(( "==== hinting %s edges =====\n",
1867 dim == AF_DIMENSION_HORZ ? "vertical" : "horizontal" ));
1868
1869 /* we begin by aligning all stems relative to the blue zone */
1870 /* if needed -- that's only for horizontal edges */
1871
1872 if ( dim == AF_DIMENSION_VERT && AF_HINTS_DO_BLUES( hints ) )
1873 {
1874 for ( edge = edges; edge < edge_limit; edge++ )
1875 {
1876 AF_Width blue;
1877 AF_Edge edge1, edge2;
1878
1879
1880 if ( edge->flags & AF_EDGE_DONE )
1881 continue;
1882
1883 blue = edge->blue_edge;
1884 edge1 = NULL;
1885 edge2 = edge->link;
1886
1887 if ( blue )
1888 {
1889 edge1 = edge;
1890 }
1891 else if ( edge2 && edge2->blue_edge )
1892 {
1893 blue = edge2->blue_edge;
1894 edge1 = edge2;
1895 edge2 = edge;
1896 }
1897
1898 if ( !edge1 )
1899 continue;
1900
1901 FT_TRACE5(( "BLUE: edge %d (opos=%.2f) snapped to (%.2f), "
1902 "was (%.2f)\n",
1903 edge1-edges, edge1->opos / 64.0, blue->fit / 64.0,
1904 edge1->pos / 64.0 ));
1905
1906 edge1->pos = blue->fit;
1907 edge1->flags |= AF_EDGE_DONE;
1908
1909 if ( edge2 && !edge2->blue_edge )
1910 {
1911 af_latin2_align_linked_edge( hints, dim, edge1, edge2 );
1912 edge2->flags |= AF_EDGE_DONE;
1913 }
1914
1915 if ( !anchor )
1916 {
1917 anchor = edge;
1918
1919 anchor_drift = ( anchor->pos - anchor->opos );
1920 if ( edge2 )
1921 anchor_drift = ( anchor_drift +
1922 ( edge2->pos - edge2->opos ) ) >> 1;
1923 }
1924 }
1925 }
1926
1927 /* now we will align all stem edges, trying to maintain the */
1928 /* relative order of stems in the glyph */
1929 for ( edge = edges; edge < edge_limit; edge++ )
1930 {
1931 AF_Edge edge2;
1932
1933
1934 if ( edge->flags & AF_EDGE_DONE )
1935 continue;
1936
1937 /* skip all non-stem edges */
1938 edge2 = edge->link;
1939 if ( !edge2 )
1940 {
1941 has_serifs++;
1942 continue;
1943 }
1944
1945 /* now align the stem */
1946
1947 /* this should not happen, but it's better to be safe */
1948 if ( edge2->blue_edge )
1949 {
1950 FT_TRACE5(( "ASSERTION FAILED for edge %d\n", edge2-edges ));
1951
1952 af_latin2_align_linked_edge( hints, dim, edge2, edge );
1953 edge->flags |= AF_EDGE_DONE;
1954 continue;
1955 }
1956
1957 if ( !anchor )
1958 {
1959 FT_Pos org_len, org_center, cur_len;
1960 FT_Pos cur_pos1, error1, error2, u_off, d_off;
1961
1962
1963 org_len = edge2->opos - edge->opos;
1964 cur_len = af_latin2_compute_stem_width( hints, dim, org_len,
1965 edge->flags,
1966 edge2->flags );
1967 if ( cur_len <= 64 )
1968 u_off = d_off = 32;
1969 else
1970 {
1971 u_off = 38;
1972 d_off = 26;
1973 }
1974
1975 if ( cur_len < 96 )
1976 {
1977 org_center = edge->opos + ( org_len >> 1 );
1978
1979 cur_pos1 = FT_PIX_ROUND( org_center );
1980
1981 error1 = org_center - ( cur_pos1 - u_off );
1982 if ( error1 < 0 )
1983 error1 = -error1;
1984
1985 error2 = org_center - ( cur_pos1 + d_off );
1986 if ( error2 < 0 )
1987 error2 = -error2;
1988
1989 if ( error1 < error2 )
1990 cur_pos1 -= u_off;
1991 else
1992 cur_pos1 += d_off;
1993
1994 edge->pos = cur_pos1 - cur_len / 2;
1995 edge2->pos = edge->pos + cur_len;
1996 }
1997 else
1998 edge->pos = FT_PIX_ROUND( edge->opos );
1999
2000 FT_TRACE5(( "ANCHOR: edge %d (opos=%.2f) and %d (opos=%.2f)"
2001 " snapped to (%.2f) (%.2f)\n",
2002 edge-edges, edge->opos / 64.0,
2003 edge2-edges, edge2->opos / 64.0,
2004 edge->pos / 64.0, edge2->pos / 64.0 ));
2005 anchor = edge;
2006
2007 edge->flags |= AF_EDGE_DONE;
2008
2009 af_latin2_align_linked_edge( hints, dim, edge, edge2 );
2010
2011 edge2->flags |= AF_EDGE_DONE;
2012
2013 anchor_drift = ( ( anchor->pos - anchor->opos ) +
2014 ( edge2->pos - edge2->opos ) ) >> 1;
2015
2016 FT_TRACE5(( "DRIFT: %.2f\n", anchor_drift/64.0 ));
2017 }
2018 else
2019 {
2020 FT_Pos org_pos, org_len, org_center, cur_center, cur_len;
2021 FT_Pos org_left, org_right;
2022
2023
2024 org_pos = edge->opos + anchor_drift;
2025 org_len = edge2->opos - edge->opos;
2026 org_center = org_pos + ( org_len >> 1 );
2027
2028 cur_len = af_latin2_compute_stem_width( hints, dim, org_len,
2029 edge->flags,
2030 edge2->flags );
2031
2032 org_left = org_pos + ( ( org_len - cur_len ) >> 1 );
2033 org_right = org_pos + ( ( org_len + cur_len ) >> 1 );
2034
2035 FT_TRACE5(( "ALIGN: left=%.2f right=%.2f ",
2036 org_left / 64.0, org_right / 64.0 ));
2037 cur_center = org_center;
2038
2039 if ( edge2->flags & AF_EDGE_DONE )
2040 {
2041 FT_TRACE5(( "\n" ));
2042 edge->pos = edge2->pos - cur_len;
2043 }
2044 else
2045 {
2046 /* we want to compare several displacement, and choose
2047 * the one that increases fitness while minimizing
2048 * distortion as well
2049 */
2050 FT_Pos displacements[6], scores[6], org, fit, delta;
2051 FT_UInt count = 0;
2052
2053 /* note: don't even try to fit tiny stems */
2054 if ( cur_len < 32 )
2055 {
2056 FT_TRACE5(( "tiny stem\n" ));
2057 goto AlignStem;
2058 }
2059
2060 /* if the span is within a single pixel, don't touch it */
2061 if ( FT_PIX_FLOOR( org_left ) == FT_PIX_CEIL( org_right ) )
2062 {
2063 FT_TRACE5(( "single pixel stem\n" ));
2064 goto AlignStem;
2065 }
2066
2067 if ( cur_len <= 96 )
2068 {
2069 /* we want to avoid the absolute worst case which is
2070 * when the left and right edges of the span each represent
2071 * about 50% of the gray. we'd better want to change this
2072 * to 25/75%, since this is much more pleasant to the eye with
2073 * very acceptable distortion
2074 */
2075 FT_Pos frac_left = org_left & 63;
2076 FT_Pos frac_right = org_right & 63;
2077
2078 if ( frac_left >= 22 && frac_left <= 42 &&
2079 frac_right >= 22 && frac_right <= 42 )
2080 {
2081 org = frac_left;
2082 fit = ( org <= 32 ) ? 16 : 48;
2083 delta = FT_ABS( fit - org );
2084 displacements[count] = fit - org;
2085 scores[count++] = delta;
2086 FT_TRACE5(( "dispA=%.2f (%d) ", ( fit - org ) / 64.0, delta ));
2087
2088 org = frac_right;
2089 fit = ( org <= 32 ) ? 16 : 48;
2090 delta = FT_ABS( fit - org );
2091 displacements[count] = fit - org;
2092 scores[count++] = delta;
2093 FT_TRACE5(( "dispB=%.2f (%d) ", ( fit - org ) / 64.0, delta ));
2094 }
2095 }
2096
2097 /* snapping the left edge to the grid */
2098 org = org_left;
2099 fit = FT_PIX_ROUND( org );
2100 delta = FT_ABS( fit - org );
2101 displacements[count] = fit - org;
2102 scores[count++] = delta;
2103 FT_TRACE5(( "dispC=%.2f (%d) ", ( fit - org ) / 64.0, delta ));
2104
2105 /* snapping the right edge to the grid */
2106 org = org_right;
2107 fit = FT_PIX_ROUND( org );
2108 delta = FT_ABS( fit - org );
2109 displacements[count] = fit - org;
2110 scores[count++] = delta;
2111 FT_TRACE5(( "dispD=%.2f (%d) ", ( fit - org ) / 64.0, delta ));
2112
2113 /* now find the best displacement */
2114 {
2115 FT_Pos best_score = scores[0];
2116 FT_Pos best_disp = displacements[0];
2117 FT_UInt nn;
2118
2119 for ( nn = 1; nn < count; nn++ )
2120 {
2121 if ( scores[nn] < best_score )
2122 {
2123 best_score = scores[nn];
2124 best_disp = displacements[nn];
2125 }
2126 }
2127
2128 cur_center = org_center + best_disp;
2129 }
2130 FT_TRACE5(( "\n" ));
2131 }
2132
2133 AlignStem:
2134 edge->pos = cur_center - ( cur_len >> 1 );
2135 edge2->pos = edge->pos + cur_len;
2136
2137 FT_TRACE5(( "STEM1: %d (opos=%.2f) to %d (opos=%.2f)"
2138 " snapped to (%.2f) and (%.2f),"
2139 " org_len=%.2f cur_len=%.2f\n",
2140 edge-edges, edge->opos / 64.0,
2141 edge2-edges, edge2->opos / 64.0,
2142 edge->pos / 64.0, edge2->pos / 64.0,
2143 org_len / 64.0, cur_len / 64.0 ));
2144
2145 edge->flags |= AF_EDGE_DONE;
2146 edge2->flags |= AF_EDGE_DONE;
2147
2148 if ( edge > edges && edge->pos < edge[-1].pos )
2149 {
2150 FT_TRACE5(( "BOUND: %d (pos=%.2f) to (%.2f)\n",
2151 edge-edges, edge->pos / 64.0, edge[-1].pos / 64.0 ));
2152 edge->pos = edge[-1].pos;
2153 }
2154 }
2155 }
2156
2157 /* make sure that lowercase m's maintain their symmetry */
2158
2159 /* In general, lowercase m's have six vertical edges if they are sans */
2160 /* serif, or twelve if they are with serifs. This implementation is */
2161 /* based on that assumption, and seems to work very well with most */
2162 /* faces. However, if for a certain face this assumption is not */
2163 /* true, the m is just rendered like before. In addition, any stem */
2164 /* correction will only be applied to symmetrical glyphs (even if the */
2165 /* glyph is not an m), so the potential for unwanted distortion is */
2166 /* relatively low. */
2167
2168 /* We don't handle horizontal edges since we can't easily assure that */
2169 /* the third (lowest) stem aligns with the base line; it might end up */
2170 /* one pixel higher or lower. */
2171
2172 #if 0
2173 {
2174 FT_Int n_edges = edge_limit - edges;
2175
2176
2177 if ( dim == AF_DIMENSION_HORZ && ( n_edges == 6 || n_edges == 12 ) )
2178 {
2179 AF_Edge edge1, edge2, edge3;
2180 FT_Pos dist1, dist2, span, delta;
2181
2182
2183 if ( n_edges == 6 )
2184 {
2185 edge1 = edges;
2186 edge2 = edges + 2;
2187 edge3 = edges + 4;
2188 }
2189 else
2190 {
2191 edge1 = edges + 1;
2192 edge2 = edges + 5;
2193 edge3 = edges + 9;
2194 }
2195
2196 dist1 = edge2->opos - edge1->opos;
2197 dist2 = edge3->opos - edge2->opos;
2198
2199 span = dist1 - dist2;
2200 if ( span < 0 )
2201 span = -span;
2202
2203 if ( span < 8 )
2204 {
2205 delta = edge3->pos - ( 2 * edge2->pos - edge1->pos );
2206 edge3->pos -= delta;
2207 if ( edge3->link )
2208 edge3->link->pos -= delta;
2209
2210 /* move the serifs along with the stem */
2211 if ( n_edges == 12 )
2212 {
2213 ( edges + 8 )->pos -= delta;
2214 ( edges + 11 )->pos -= delta;
2215 }
2216
2217 edge3->flags |= AF_EDGE_DONE;
2218 if ( edge3->link )
2219 edge3->link->flags |= AF_EDGE_DONE;
2220 }
2221 }
2222 }
2223 #endif
2224
2225 if ( has_serifs || !anchor )
2226 {
2227 /*
2228 * now hint the remaining edges (serifs and single) in order
2229 * to complete our processing
2230 */
2231 for ( edge = edges; edge < edge_limit; edge++ )
2232 {
2233 FT_Pos delta;
2234
2235
2236 if ( edge->flags & AF_EDGE_DONE )
2237 continue;
2238
2239 delta = 1000;
2240
2241 if ( edge->serif )
2242 {
2243 delta = edge->serif->opos - edge->opos;
2244 if ( delta < 0 )
2245 delta = -delta;
2246 }
2247
2248 if ( delta < 64 + 16 )
2249 {
2250 af_latin2_align_serif_edge( hints, edge->serif, edge );
2251 FT_TRACE5(( "SERIF: edge %d (opos=%.2f) serif to %d (opos=%.2f)"
2252 " aligned to (%.2f)\n",
2253 edge-edges, edge->opos / 64.0,
2254 edge->serif - edges, edge->serif->opos / 64.0,
2255 edge->pos / 64.0 ));
2256 }
2257 else if ( !anchor )
2258 {
2259 FT_TRACE5(( "SERIF_ANCHOR: edge %d (opos=%.2f)"
2260 " snapped to (%.2f)\n",
2261 edge-edges, edge->opos / 64.0, edge->pos / 64.0 ));
2262 edge->pos = FT_PIX_ROUND( edge->opos );
2263 anchor = edge;
2264 }
2265 else
2266 {
2267 AF_Edge before, after;
2268
2269
2270 for ( before = edge - 1; before >= edges; before-- )
2271 if ( before->flags & AF_EDGE_DONE )
2272 break;
2273
2274 for ( after = edge + 1; after < edge_limit; after++ )
2275 if ( after->flags & AF_EDGE_DONE )
2276 break;
2277
2278 if ( before >= edges && before < edge &&
2279 after < edge_limit && after > edge )
2280 {
2281 if ( after->opos == before->opos )
2282 edge->pos = before->pos;
2283 else
2284 edge->pos = before->pos +
2285 FT_MulDiv( edge->opos - before->opos,
2286 after->pos - before->pos,
2287 after->opos - before->opos );
2288 FT_TRACE5(( "SERIF_LINK1: edge %d (opos=%.2f) snapped to (%.2f)"
2289 " from %d (opos=%.2f)\n",
2290 edge-edges, edge->opos / 64.0, edge->pos / 64.0,
2291 before - edges, before->opos / 64.0 ));
2292 }
2293 else
2294 {
2295 edge->pos = anchor->pos +
2296 ( ( edge->opos - anchor->opos + 16 ) & ~31 );
2297
2298 FT_TRACE5(( "SERIF_LINK2: edge %d (opos=%.2f)"
2299 " snapped to (%.2f)\n",
2300 edge-edges, edge->opos / 64.0, edge->pos / 64.0 ));
2301 }
2302 }
2303
2304 edge->flags |= AF_EDGE_DONE;
2305
2306 if ( edge > edges && edge->pos < edge[-1].pos )
2307 edge->pos = edge[-1].pos;
2308
2309 if ( edge + 1 < edge_limit &&
2310 edge[1].flags & AF_EDGE_DONE &&
2311 edge->pos > edge[1].pos )
2312 edge->pos = edge[1].pos;
2313 }
2314 }
2315 }
2316
2317
2318 static FT_Error
2319 af_latin2_hints_apply( FT_UInt glyph_index,
2320 AF_GlyphHints hints,
2321 FT_Outline* outline,
2322 AF_LatinMetrics metrics )
2323 {
2324 FT_Error error;
2325 int dim;
2326
2327 FT_UNUSED( glyph_index );
2328
2329
2330 error = af_glyph_hints_reload( hints, outline );
2331 if ( error )
2332 goto Exit;
2333
2334 /* analyze glyph outline */
2335 #ifdef AF_CONFIG_OPTION_USE_WARPER
2336 if ( ( metrics->root.scaler.render_mode == FT_RENDER_MODE_LIGHT &&
2337 AF_HINTS_DO_WARP( hints ) ) ||
2338 AF_HINTS_DO_HORIZONTAL( hints ) )
2339 #else
2340 if ( AF_HINTS_DO_HORIZONTAL( hints ) )
2341 #endif
2342 {
2343 error = af_latin2_hints_detect_features( hints, AF_DIMENSION_HORZ );
2344 if ( error )
2345 goto Exit;
2346 }
2347
2348 if ( AF_HINTS_DO_VERTICAL( hints ) )
2349 {
2350 error = af_latin2_hints_detect_features( hints, AF_DIMENSION_VERT );
2351 if ( error )
2352 goto Exit;
2353
2354 af_latin2_hints_compute_blue_edges( hints, metrics );
2355 }
2356
2357 /* grid-fit the outline */
2358 for ( dim = 0; dim < AF_DIMENSION_MAX; dim++ )
2359 {
2360 #ifdef AF_CONFIG_OPTION_USE_WARPER
2361 if ( dim == AF_DIMENSION_HORZ &&
2362 metrics->root.scaler.render_mode == FT_RENDER_MODE_LIGHT &&
2363 AF_HINTS_DO_WARP( hints ) )
2364 {
2365 AF_WarperRec warper;
2366 FT_Fixed scale;
2367 FT_Pos delta;
2368
2369
2370 af_warper_compute( &warper, hints, dim, &scale, &delta );
2371 af_glyph_hints_scale_dim( hints, dim, scale, delta );
2372 continue;
2373 }
2374 #endif /* AF_CONFIG_OPTION_USE_WARPER */
2375
2376 if ( ( dim == AF_DIMENSION_HORZ && AF_HINTS_DO_HORIZONTAL( hints ) ) ||
2377 ( dim == AF_DIMENSION_VERT && AF_HINTS_DO_VERTICAL( hints ) ) )
2378 {
2379 af_latin2_hint_edges( hints, (AF_Dimension)dim );
2380 af_glyph_hints_align_edge_points( hints, (AF_Dimension)dim );
2381 af_glyph_hints_align_strong_points( hints, (AF_Dimension)dim );
2382 af_glyph_hints_align_weak_points( hints, (AF_Dimension)dim );
2383 }
2384 }
2385 af_glyph_hints_save( hints, outline );
2386
2387 Exit:
2388 return error;
2389 }
2390
2391
2392 /*************************************************************************/
2393 /*************************************************************************/
2394 /***** *****/
2395 /***** L A T I N S C R I P T C L A S S *****/
2396 /***** *****/
2397 /*************************************************************************/
2398 /*************************************************************************/
2399
2400
2401 AF_DEFINE_WRITING_SYSTEM_CLASS(
2402 af_latin2_writing_system_class,
2403
2404 AF_WRITING_SYSTEM_LATIN2,
2405
2406 sizeof ( AF_LatinMetricsRec ),
2407
2408 (AF_WritingSystem_InitMetricsFunc) af_latin2_metrics_init,
2409 (AF_WritingSystem_ScaleMetricsFunc)af_latin2_metrics_scale,
2410 (AF_WritingSystem_DoneMetricsFunc) NULL,
2411 (AF_WritingSystem_GetStdWidthsFunc)af_latin2_get_standard_widths,
2412
2413 (AF_WritingSystem_InitHintsFunc) af_latin2_hints_init,
2414 (AF_WritingSystem_ApplyHintsFunc) af_latin2_hints_apply
2415 )
2416
2417
2418 /* END */
A free Windows-compatible Operating System