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1 /****************************************************************************
2  *
3  * afcjk.c
4  *
5  *   Auto-fitter hinting routines for CJK writing system (body).
6  *
7  * Copyright (C) 2006-2021 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    * The algorithm is based on akito's autohint patch, archived at
20    *
21    * https://web.archive.org/web/20051219160454/http://www.kde.gr.jp:80/~akito/patch/freetype2/2.1.7/
22    *
23    */
24 
25 #include <freetype/ftadvanc.h>
26 #include <freetype/internal/ftdebug.h>
27 
28 #include "afglobal.h"
29 #include "aflatin.h"
30 #include "afcjk.h"
31 
32 
33 #ifdef AF_CONFIG_OPTION_CJK
34 
35 #undef AF_CONFIG_OPTION_CJK_BLUE_HANI_VERT
36 
37 #include "aferrors.h"
38 
39 
40   /**************************************************************************
41    *
42    * The macro FT_COMPONENT is used in trace mode.  It is an implicit
43    * parameter of the FT_TRACE() and FT_ERROR() macros, used to print/log
44    * messages during execution.
45    */
46 #undef  FT_COMPONENT
47 #define FT_COMPONENT  afcjk
48 
49 
50   /*************************************************************************/
51   /*************************************************************************/
52   /*****                                                               *****/
53   /*****              C J K   G L O B A L   M E T R I C S              *****/
54   /*****                                                               *****/
55   /*************************************************************************/
56   /*************************************************************************/
57 
58 
59   /* Basically the Latin version with AF_CJKMetrics */
60   /* to replace AF_LatinMetrics.                    */
61 
62   FT_LOCAL_DEF( void )
af_cjk_metrics_init_widths(AF_CJKMetrics metrics,FT_Face face)63   af_cjk_metrics_init_widths( AF_CJKMetrics  metrics,
64                               FT_Face        face )
65   {
66     /* scan the array of segments in each direction */
67     AF_GlyphHintsRec  hints[1];
68 
69 
70     FT_TRACE5(( "\n" ));
71     FT_TRACE5(( "cjk standard widths computation (style `%s')\n",
72                 af_style_names[metrics->root.style_class->style] ));
73     FT_TRACE5(( "===================================================\n" ));
74     FT_TRACE5(( "\n" ));
75 
76     af_glyph_hints_init( hints, face->memory );
77 
78     metrics->axis[AF_DIMENSION_HORZ].width_count = 0;
79     metrics->axis[AF_DIMENSION_VERT].width_count = 0;
80 
81     {
82       FT_Error          error;
83       FT_ULong          glyph_index;
84       int               dim;
85       AF_CJKMetricsRec  dummy[1];
86       AF_Scaler         scaler = &dummy->root.scaler;
87 
88       AF_StyleClass   style_class  = metrics->root.style_class;
89       AF_ScriptClass  script_class = af_script_classes[style_class->script];
90 
91       /* If HarfBuzz is not available, we need a pointer to a single */
92       /* unsigned long value.                                        */
93 #ifdef FT_CONFIG_OPTION_USE_HARFBUZZ
94       void*     shaper_buf;
95 #else
96       FT_ULong  shaper_buf_;
97       void*     shaper_buf = &shaper_buf_;
98 #endif
99 
100       const char*  p;
101 
102 #ifdef FT_DEBUG_LEVEL_TRACE
103       FT_ULong  ch = 0;
104 #endif
105 
106       p = script_class->standard_charstring;
107 
108 #ifdef FT_CONFIG_OPTION_USE_HARFBUZZ
109       shaper_buf = af_shaper_buf_create( face );
110 #endif
111 
112       /* We check a list of standard characters.  The first match wins. */
113 
114       glyph_index = 0;
115       while ( *p )
116       {
117         unsigned int  num_idx;
118 
119 #ifdef FT_DEBUG_LEVEL_TRACE
120         const char*  p_old;
121 #endif
122 
123 
124         while ( *p == ' ' )
125           p++;
126 
127 #ifdef FT_DEBUG_LEVEL_TRACE
128         p_old = p;
129         GET_UTF8_CHAR( ch, p_old );
130 #endif
131 
132         /* reject input that maps to more than a single glyph */
133         p = af_shaper_get_cluster( p, &metrics->root, shaper_buf, &num_idx );
134         if ( num_idx > 1 )
135           continue;
136 
137         /* otherwise exit loop if we have a result */
138         glyph_index = af_shaper_get_elem( &metrics->root,
139                                           shaper_buf,
140                                           0,
141                                           NULL,
142                                           NULL );
143         if ( glyph_index )
144           break;
145       }
146 
147       af_shaper_buf_destroy( face, shaper_buf );
148 
149       if ( !glyph_index )
150         goto Exit;
151 
152       if ( !glyph_index )
153         goto Exit;
154 
155       FT_TRACE5(( "standard character: U+%04lX (glyph index %ld)\n",
156                   ch, glyph_index ));
157 
158       error = FT_Load_Glyph( face, glyph_index, FT_LOAD_NO_SCALE );
159       if ( error || face->glyph->outline.n_points <= 0 )
160         goto Exit;
161 
162       FT_ZERO( dummy );
163 
164       dummy->units_per_em = metrics->units_per_em;
165 
166       scaler->x_scale = 0x10000L;
167       scaler->y_scale = 0x10000L;
168       scaler->x_delta = 0;
169       scaler->y_delta = 0;
170 
171       scaler->face        = face;
172       scaler->render_mode = FT_RENDER_MODE_NORMAL;
173       scaler->flags       = 0;
174 
175       af_glyph_hints_rescale( hints, (AF_StyleMetrics)dummy );
176 
177       error = af_glyph_hints_reload( hints, &face->glyph->outline );
178       if ( error )
179         goto Exit;
180 
181       for ( dim = 0; dim < AF_DIMENSION_MAX; dim++ )
182       {
183         AF_CJKAxis    axis    = &metrics->axis[dim];
184         AF_AxisHints  axhints = &hints->axis[dim];
185         AF_Segment    seg, limit, link;
186         FT_UInt       num_widths = 0;
187 
188 
189         error = af_latin_hints_compute_segments( hints,
190                                                  (AF_Dimension)dim );
191         if ( error )
192           goto Exit;
193 
194         /*
195          * We assume that the glyphs selected for the stem width
196          * computation are `featureless' enough so that the linking
197          * algorithm works fine without adjustments of its scoring
198          * function.
199          */
200         af_latin_hints_link_segments( hints,
201                                       0,
202                                       NULL,
203                                       (AF_Dimension)dim );
204 
205         seg   = axhints->segments;
206         limit = seg + axhints->num_segments;
207 
208         for ( ; seg < limit; seg++ )
209         {
210           link = seg->link;
211 
212           /* we only consider stem segments there! */
213           if ( link && link->link == seg && link > seg )
214           {
215             FT_Pos  dist;
216 
217 
218             dist = seg->pos - link->pos;
219             if ( dist < 0 )
220               dist = -dist;
221 
222             if ( num_widths < AF_CJK_MAX_WIDTHS )
223               axis->widths[num_widths++].org = dist;
224           }
225         }
226 
227         /* this also replaces multiple almost identical stem widths */
228         /* with a single one (the value 100 is heuristic)           */
229         af_sort_and_quantize_widths( &num_widths, axis->widths,
230                                      dummy->units_per_em / 100 );
231         axis->width_count = num_widths;
232       }
233 
234     Exit:
235       for ( dim = 0; dim < AF_DIMENSION_MAX; dim++ )
236       {
237         AF_CJKAxis  axis = &metrics->axis[dim];
238         FT_Pos      stdw;
239 
240 
241         stdw = ( axis->width_count > 0 ) ? axis->widths[0].org
242                                          : AF_LATIN_CONSTANT( metrics, 50 );
243 
244         /* let's try 20% of the smallest width */
245         axis->edge_distance_threshold = stdw / 5;
246         axis->standard_width          = stdw;
247         axis->extra_light             = 0;
248 
249 #ifdef FT_DEBUG_LEVEL_TRACE
250         {
251           FT_UInt  i;
252 
253 
254           FT_TRACE5(( "%s widths:\n",
255                       dim == AF_DIMENSION_VERT ? "horizontal"
256                                                : "vertical" ));
257 
258           FT_TRACE5(( "  %ld (standard)", axis->standard_width ));
259           for ( i = 1; i < axis->width_count; i++ )
260             FT_TRACE5(( " %ld", axis->widths[i].org ));
261 
262           FT_TRACE5(( "\n" ));
263         }
264 #endif
265       }
266     }
267 
268     FT_TRACE5(( "\n" ));
269 
270     af_glyph_hints_done( hints );
271   }
272 
273 
274   /* Find all blue zones. */
275 
276   static void
af_cjk_metrics_init_blues(AF_CJKMetrics metrics,FT_Face face)277   af_cjk_metrics_init_blues( AF_CJKMetrics  metrics,
278                              FT_Face        face )
279   {
280     FT_Pos      fills[AF_BLUE_STRING_MAX_LEN];
281     FT_Pos      flats[AF_BLUE_STRING_MAX_LEN];
282 
283     FT_UInt     num_fills;
284     FT_UInt     num_flats;
285 
286     FT_Bool     fill;
287 
288     AF_CJKBlue  blue;
289     FT_Error    error;
290     AF_CJKAxis  axis;
291     FT_Outline  outline;
292 
293     AF_StyleClass  sc = metrics->root.style_class;
294 
295     AF_Blue_Stringset         bss = sc->blue_stringset;
296     const AF_Blue_StringRec*  bs  = &af_blue_stringsets[bss];
297 
298     /* If HarfBuzz is not available, we need a pointer to a single */
299     /* unsigned long value.                                        */
300 #ifdef FT_CONFIG_OPTION_USE_HARFBUZZ
301     void*     shaper_buf;
302 #else
303     FT_ULong  shaper_buf_;
304     void*     shaper_buf = &shaper_buf_;
305 #endif
306 
307 
308     /* we walk over the blue character strings as specified in the   */
309     /* style's entry in the `af_blue_stringset' array, computing its */
310     /* extremum points (depending on the string properties)          */
311 
312     FT_TRACE5(( "cjk blue zones computation\n" ));
313     FT_TRACE5(( "==========================\n" ));
314     FT_TRACE5(( "\n" ));
315 
316 #ifdef FT_CONFIG_OPTION_USE_HARFBUZZ
317     shaper_buf = af_shaper_buf_create( face );
318 #endif
319 
320     for ( ; bs->string != AF_BLUE_STRING_MAX; bs++ )
321     {
322       const char*  p = &af_blue_strings[bs->string];
323       FT_Pos*      blue_ref;
324       FT_Pos*      blue_shoot;
325 
326 
327       if ( AF_CJK_IS_HORIZ_BLUE( bs ) )
328         axis = &metrics->axis[AF_DIMENSION_HORZ];
329       else
330         axis = &metrics->axis[AF_DIMENSION_VERT];
331 
332 #ifdef FT_DEBUG_LEVEL_TRACE
333       {
334         FT_String*  cjk_blue_name[4] =
335         {
336           (FT_String*)"bottom",    /* --   , --  */
337           (FT_String*)"top",       /* --   , TOP */
338           (FT_String*)"left",      /* HORIZ, --  */
339           (FT_String*)"right"      /* HORIZ, TOP */
340         };
341 
342 
343         FT_TRACE5(( "blue zone %d (%s):\n",
344                     axis->blue_count,
345                     cjk_blue_name[AF_CJK_IS_HORIZ_BLUE( bs ) |
346                                   AF_CJK_IS_TOP_BLUE( bs )   ] ));
347       }
348 #endif /* FT_DEBUG_LEVEL_TRACE */
349 
350       num_fills = 0;
351       num_flats = 0;
352 
353       fill = 1;  /* start with characters that define fill values */
354       FT_TRACE5(( "  [overshoot values]\n" ));
355 
356       while ( *p )
357       {
358         FT_ULong    glyph_index;
359         FT_Pos      best_pos;       /* same as points.y or points.x, resp. */
360         FT_Int      best_point;
361         FT_Vector*  points;
362 
363         unsigned int  num_idx;
364 
365 #ifdef FT_DEBUG_LEVEL_TRACE
366         const char*  p_old;
367         FT_ULong     ch;
368 #endif
369 
370 
371         while ( *p == ' ' )
372           p++;
373 
374 #ifdef FT_DEBUG_LEVEL_TRACE
375         p_old = p;
376         GET_UTF8_CHAR( ch, p_old );
377 #endif
378 
379         /* switch to characters that define flat values */
380         if ( *p == '|' )
381         {
382           fill = 0;
383           FT_TRACE5(( "  [reference values]\n" ));
384           p++;
385           continue;
386         }
387 
388         /* reject input that maps to more than a single glyph */
389         p = af_shaper_get_cluster( p, &metrics->root, shaper_buf, &num_idx );
390         if ( num_idx > 1 )
391           continue;
392 
393         /* load the character in the face -- skip unknown or empty ones */
394         glyph_index = af_shaper_get_elem( &metrics->root,
395                                           shaper_buf,
396                                           0,
397                                           NULL,
398                                           NULL );
399         if ( glyph_index == 0 )
400         {
401           FT_TRACE5(( "  U+%04lX unavailable\n", ch ));
402           continue;
403         }
404 
405         error   = FT_Load_Glyph( face, glyph_index, FT_LOAD_NO_SCALE );
406         outline = face->glyph->outline;
407         if ( error || outline.n_points <= 2 )
408         {
409           FT_TRACE5(( "  U+%04lX contains no (usable) outlines\n", ch ));
410           continue;
411         }
412 
413         /* now compute min or max point indices and coordinates */
414         points     = outline.points;
415         best_point = -1;
416         best_pos   = 0;  /* make compiler happy */
417 
418         {
419           FT_Int  nn;
420           FT_Int  first = 0;
421           FT_Int  last  = -1;
422 
423 
424           for ( nn = 0; nn < outline.n_contours; first = last + 1, nn++ )
425           {
426             FT_Int  pp;
427 
428 
429             last = outline.contours[nn];
430 
431             /* Avoid single-point contours since they are never rasterized. */
432             /* In some fonts, they correspond to mark attachment points     */
433             /* which are way outside of the glyph's real outline.           */
434             if ( last <= first )
435               continue;
436 
437             if ( AF_CJK_IS_HORIZ_BLUE( bs ) )
438             {
439               if ( AF_CJK_IS_RIGHT_BLUE( bs ) )
440               {
441                 for ( pp = first; pp <= last; pp++ )
442                   if ( best_point < 0 || points[pp].x > best_pos )
443                   {
444                     best_point = pp;
445                     best_pos   = points[pp].x;
446                   }
447               }
448               else
449               {
450                 for ( pp = first; pp <= last; pp++ )
451                   if ( best_point < 0 || points[pp].x < best_pos )
452                   {
453                     best_point = pp;
454                     best_pos   = points[pp].x;
455                   }
456               }
457             }
458             else
459             {
460               if ( AF_CJK_IS_TOP_BLUE( bs ) )
461               {
462                 for ( pp = first; pp <= last; pp++ )
463                   if ( best_point < 0 || points[pp].y > best_pos )
464                   {
465                     best_point = pp;
466                     best_pos   = points[pp].y;
467                   }
468               }
469               else
470               {
471                 for ( pp = first; pp <= last; pp++ )
472                   if ( best_point < 0 || points[pp].y < best_pos )
473                   {
474                     best_point = pp;
475                     best_pos   = points[pp].y;
476                   }
477               }
478             }
479           }
480 
481           FT_TRACE5(( "  U+%04lX: best_pos = %5ld\n", ch, best_pos ));
482         }
483 
484         if ( fill )
485           fills[num_fills++] = best_pos;
486         else
487           flats[num_flats++] = best_pos;
488 
489       } /* end while loop */
490 
491       if ( num_flats == 0 && num_fills == 0 )
492       {
493         /*
494          * we couldn't find a single glyph to compute this blue zone,
495          * we will simply ignore it then
496          */
497         FT_TRACE5(( "  empty\n" ));
498         continue;
499       }
500 
501       /* we have computed the contents of the `fill' and `flats' tables,   */
502       /* now determine the reference and overshoot position of the blue -- */
503       /* we simply take the median value after a simple sort               */
504       af_sort_pos( num_fills, fills );
505       af_sort_pos( num_flats, flats );
506 
507       blue       = &axis->blues[axis->blue_count];
508       blue_ref   = &blue->ref.org;
509       blue_shoot = &blue->shoot.org;
510 
511       axis->blue_count++;
512 
513       if ( num_flats == 0 )
514       {
515         *blue_ref   =
516         *blue_shoot = fills[num_fills / 2];
517       }
518       else if ( num_fills == 0 )
519       {
520         *blue_ref   =
521         *blue_shoot = flats[num_flats / 2];
522       }
523       else
524       {
525         *blue_ref   = fills[num_fills / 2];
526         *blue_shoot = flats[num_flats / 2];
527       }
528 
529       /* make sure blue_ref >= blue_shoot for top/right or */
530       /* vice versa for bottom/left                        */
531       if ( *blue_shoot != *blue_ref )
532       {
533         FT_Pos   ref       = *blue_ref;
534         FT_Pos   shoot     = *blue_shoot;
535         FT_Bool  under_ref = FT_BOOL( shoot < ref );
536 
537 
538         /* AF_CJK_IS_TOP_BLUE covers `right' and `top' */
539         if ( AF_CJK_IS_TOP_BLUE( bs ) ^ under_ref )
540         {
541           *blue_ref   =
542           *blue_shoot = ( shoot + ref ) / 2;
543 
544           FT_TRACE5(( "  [reference smaller than overshoot,"
545                       " taking mean value]\n" ));
546         }
547       }
548 
549       blue->flags = 0;
550       if ( AF_CJK_IS_TOP_BLUE( bs ) )
551         blue->flags |= AF_CJK_BLUE_TOP;
552 
553       FT_TRACE5(( "    -> reference = %ld\n", *blue_ref ));
554       FT_TRACE5(( "       overshoot = %ld\n", *blue_shoot ));
555 
556     } /* end for loop */
557 
558     af_shaper_buf_destroy( face, shaper_buf );
559 
560     FT_TRACE5(( "\n" ));
561 
562     return;
563   }
564 
565 
566   /* Basically the Latin version with type AF_CJKMetrics for metrics. */
567 
568   FT_LOCAL_DEF( void )
af_cjk_metrics_check_digits(AF_CJKMetrics metrics,FT_Face face)569   af_cjk_metrics_check_digits( AF_CJKMetrics  metrics,
570                                FT_Face        face )
571   {
572     FT_Bool   started = 0, same_width = 1;
573     FT_Fixed  advance = 0, old_advance = 0;
574 
575     /* If HarfBuzz is not available, we need a pointer to a single */
576     /* unsigned long value.                                        */
577 #ifdef FT_CONFIG_OPTION_USE_HARFBUZZ
578     void*     shaper_buf;
579 #else
580     FT_ULong  shaper_buf_;
581     void*     shaper_buf = &shaper_buf_;
582 #endif
583 
584     /* in all supported charmaps, digits have character codes 0x30-0x39 */
585     const char   digits[] = "0 1 2 3 4 5 6 7 8 9";
586     const char*  p;
587 
588 
589     p = digits;
590 
591 #ifdef FT_CONFIG_OPTION_USE_HARFBUZZ
592     shaper_buf = af_shaper_buf_create( face );
593 #endif
594 
595     while ( *p )
596     {
597       FT_ULong      glyph_index;
598       unsigned int  num_idx;
599 
600 
601       /* reject input that maps to more than a single glyph */
602       p = af_shaper_get_cluster( p, &metrics->root, shaper_buf, &num_idx );
603       if ( num_idx > 1 )
604         continue;
605 
606       glyph_index = af_shaper_get_elem( &metrics->root,
607                                         shaper_buf,
608                                         0,
609                                         &advance,
610                                         NULL );
611       if ( !glyph_index )
612         continue;
613 
614       if ( started )
615       {
616         if ( advance != old_advance )
617         {
618           same_width = 0;
619           break;
620         }
621       }
622       else
623       {
624         old_advance = advance;
625         started     = 1;
626       }
627     }
628 
629     af_shaper_buf_destroy( face, shaper_buf );
630 
631     metrics->root.digits_have_same_width = same_width;
632   }
633 
634 
635   /* Initialize global metrics. */
636 
637   FT_LOCAL_DEF( FT_Error )
af_cjk_metrics_init(AF_CJKMetrics metrics,FT_Face face)638   af_cjk_metrics_init( AF_CJKMetrics  metrics,
639                        FT_Face        face )
640   {
641     FT_CharMap  oldmap = face->charmap;
642 
643 
644     metrics->units_per_em = face->units_per_EM;
645 
646     if ( !FT_Select_Charmap( face, FT_ENCODING_UNICODE ) )
647     {
648       af_cjk_metrics_init_widths( metrics, face );
649       af_cjk_metrics_init_blues( metrics, face );
650       af_cjk_metrics_check_digits( metrics, face );
651     }
652 
653     FT_Set_Charmap( face, oldmap );
654     return FT_Err_Ok;
655   }
656 
657 
658   /* Adjust scaling value, then scale and shift widths   */
659   /* and blue zones (if applicable) for given dimension. */
660 
661   static void
af_cjk_metrics_scale_dim(AF_CJKMetrics metrics,AF_Scaler scaler,AF_Dimension dim)662   af_cjk_metrics_scale_dim( AF_CJKMetrics  metrics,
663                             AF_Scaler      scaler,
664                             AF_Dimension   dim )
665   {
666     FT_Fixed    scale;
667     FT_Pos      delta;
668     AF_CJKAxis  axis;
669     FT_UInt     nn;
670 
671 
672     if ( dim == AF_DIMENSION_HORZ )
673     {
674       scale = scaler->x_scale;
675       delta = scaler->x_delta;
676     }
677     else
678     {
679       scale = scaler->y_scale;
680       delta = scaler->y_delta;
681     }
682 
683     axis = &metrics->axis[dim];
684 
685     if ( axis->org_scale == scale && axis->org_delta == delta )
686       return;
687 
688     axis->org_scale = scale;
689     axis->org_delta = delta;
690 
691     axis->scale = scale;
692     axis->delta = delta;
693 
694     /* scale the blue zones */
695     for ( nn = 0; nn < axis->blue_count; nn++ )
696     {
697       AF_CJKBlue  blue = &axis->blues[nn];
698       FT_Pos      dist;
699 
700 
701       blue->ref.cur   = FT_MulFix( blue->ref.org, scale ) + delta;
702       blue->ref.fit   = blue->ref.cur;
703       blue->shoot.cur = FT_MulFix( blue->shoot.org, scale ) + delta;
704       blue->shoot.fit = blue->shoot.cur;
705       blue->flags    &= ~AF_CJK_BLUE_ACTIVE;
706 
707       /* a blue zone is only active if it is less than 3/4 pixels tall */
708       dist = FT_MulFix( blue->ref.org - blue->shoot.org, scale );
709       if ( dist <= 48 && dist >= -48 )
710       {
711         FT_Pos  delta1, delta2;
712 
713 
714         blue->ref.fit  = FT_PIX_ROUND( blue->ref.cur );
715 
716         /* shoot is under shoot for cjk */
717         delta1 = FT_DivFix( blue->ref.fit, scale ) - blue->shoot.org;
718         delta2 = delta1;
719         if ( delta1 < 0 )
720           delta2 = -delta2;
721 
722         delta2 = FT_MulFix( delta2, scale );
723 
724         FT_TRACE5(( "delta: %ld", delta1 ));
725         if ( delta2 < 32 )
726           delta2 = 0;
727 #if 0
728         else if ( delta2 < 64 )
729           delta2 = 32 + ( ( ( delta2 - 32 ) + 16 ) & ~31 );
730 #endif
731         else
732           delta2 = FT_PIX_ROUND( delta2 );
733         FT_TRACE5(( "/%ld\n", delta2 ));
734 
735         if ( delta1 < 0 )
736           delta2 = -delta2;
737 
738         blue->shoot.fit = blue->ref.fit - delta2;
739 
740         FT_TRACE5(( ">> active cjk blue zone %c%d[%ld/%ld]:\n",
741                     ( dim == AF_DIMENSION_HORZ ) ? 'H' : 'V',
742                     nn, blue->ref.org, blue->shoot.org ));
743         FT_TRACE5(( "     ref:   cur=%.2f fit=%.2f\n",
744                     blue->ref.cur / 64.0, blue->ref.fit / 64.0 ));
745         FT_TRACE5(( "     shoot: cur=%.2f fit=%.2f\n",
746                     blue->shoot.cur / 64.0, blue->shoot.fit / 64.0 ));
747 
748         blue->flags |= AF_CJK_BLUE_ACTIVE;
749       }
750     }
751   }
752 
753 
754   /* Scale global values in both directions. */
755 
756   FT_LOCAL_DEF( void )
af_cjk_metrics_scale(AF_CJKMetrics metrics,AF_Scaler scaler)757   af_cjk_metrics_scale( AF_CJKMetrics  metrics,
758                         AF_Scaler      scaler )
759   {
760     /* we copy the whole structure since the x and y scaling values */
761     /* are not modified, contrary to e.g. the `latin' auto-hinter   */
762     metrics->root.scaler = *scaler;
763 
764     af_cjk_metrics_scale_dim( metrics, scaler, AF_DIMENSION_HORZ );
765     af_cjk_metrics_scale_dim( metrics, scaler, AF_DIMENSION_VERT );
766   }
767 
768 
769   /* Extract standard_width from writing system/script specific */
770   /* metrics class.                                             */
771 
772   FT_LOCAL_DEF( void )
af_cjk_get_standard_widths(AF_CJKMetrics metrics,FT_Pos * stdHW,FT_Pos * stdVW)773   af_cjk_get_standard_widths( AF_CJKMetrics  metrics,
774                               FT_Pos*        stdHW,
775                               FT_Pos*        stdVW )
776   {
777     if ( stdHW )
778       *stdHW = metrics->axis[AF_DIMENSION_VERT].standard_width;
779 
780     if ( stdVW )
781       *stdVW = metrics->axis[AF_DIMENSION_HORZ].standard_width;
782   }
783 
784 
785   /*************************************************************************/
786   /*************************************************************************/
787   /*****                                                               *****/
788   /*****              C J K   G L Y P H   A N A L Y S I S              *****/
789   /*****                                                               *****/
790   /*************************************************************************/
791   /*************************************************************************/
792 
793 
794   /* Walk over all contours and compute its segments. */
795 
796   static FT_Error
af_cjk_hints_compute_segments(AF_GlyphHints hints,AF_Dimension dim)797   af_cjk_hints_compute_segments( AF_GlyphHints  hints,
798                                  AF_Dimension   dim )
799   {
800     AF_AxisHints  axis          = &hints->axis[dim];
801     AF_Segment    segments      = axis->segments;
802     AF_Segment    segment_limit = FT_OFFSET( segments, axis->num_segments );
803     FT_Error      error;
804     AF_Segment    seg;
805 
806 
807     error = af_latin_hints_compute_segments( hints, dim );
808     if ( error )
809       return error;
810 
811     /* a segment is round if it doesn't have successive */
812     /* on-curve points.                                 */
813     for ( seg = segments; seg < segment_limit; seg++ )
814     {
815       AF_Point  pt   = seg->first;
816       AF_Point  last = seg->last;
817       FT_UInt   f0   = pt->flags & AF_FLAG_CONTROL;
818       FT_UInt   f1;
819 
820 
821       seg->flags &= ~AF_EDGE_ROUND;
822 
823       for ( ; pt != last; f0 = f1 )
824       {
825         pt = pt->next;
826         f1 = pt->flags & AF_FLAG_CONTROL;
827 
828         if ( !f0 && !f1 )
829           break;
830 
831         if ( pt == last )
832           seg->flags |= AF_EDGE_ROUND;
833       }
834     }
835 
836     return FT_Err_Ok;
837   }
838 
839 
840   static void
af_cjk_hints_link_segments(AF_GlyphHints hints,AF_Dimension dim)841   af_cjk_hints_link_segments( AF_GlyphHints  hints,
842                               AF_Dimension   dim )
843   {
844     AF_AxisHints  axis          = &hints->axis[dim];
845     AF_Segment    segments      = axis->segments;
846     AF_Segment    segment_limit = segments + axis->num_segments;
847     AF_Direction  major_dir     = axis->major_dir;
848     AF_Segment    seg1, seg2;
849     FT_Pos        len_threshold;
850     FT_Pos        dist_threshold;
851 
852 
853     len_threshold = AF_LATIN_CONSTANT( hints->metrics, 8 );
854 
855     dist_threshold = ( dim == AF_DIMENSION_HORZ ) ? hints->x_scale
856                                                   : hints->y_scale;
857     dist_threshold = FT_DivFix( 64 * 3, dist_threshold );
858 
859     /* now compare each segment to the others */
860     for ( seg1 = segments; seg1 < segment_limit; seg1++ )
861     {
862       if ( seg1->dir != major_dir )
863         continue;
864 
865       for ( seg2 = segments; seg2 < segment_limit; seg2++ )
866         if ( seg2 != seg1 && seg1->dir + seg2->dir == 0 )
867         {
868           FT_Pos  dist = seg2->pos - seg1->pos;
869 
870 
871           if ( dist < 0 )
872             continue;
873 
874           {
875             FT_Pos  min = seg1->min_coord;
876             FT_Pos  max = seg1->max_coord;
877             FT_Pos  len;
878 
879 
880             if ( min < seg2->min_coord )
881               min = seg2->min_coord;
882 
883             if ( max > seg2->max_coord )
884               max = seg2->max_coord;
885 
886             len = max - min;
887             if ( len >= len_threshold )
888             {
889               if ( dist * 8 < seg1->score * 9                        &&
890                    ( dist * 8 < seg1->score * 7 || seg1->len < len ) )
891               {
892                 seg1->score = dist;
893                 seg1->len   = len;
894                 seg1->link  = seg2;
895               }
896 
897               if ( dist * 8 < seg2->score * 9                        &&
898                    ( dist * 8 < seg2->score * 7 || seg2->len < len ) )
899               {
900                 seg2->score = dist;
901                 seg2->len   = len;
902                 seg2->link  = seg1;
903               }
904             }
905           }
906         }
907     }
908 
909     /*
910      * now compute the `serif' segments
911      *
912      * In Hanzi, some strokes are wider on one or both of the ends.
913      * We either identify the stems on the ends as serifs or remove
914      * the linkage, depending on the length of the stems.
915      *
916      */
917 
918     {
919       AF_Segment  link1, link2;
920 
921 
922       for ( seg1 = segments; seg1 < segment_limit; seg1++ )
923       {
924         link1 = seg1->link;
925         if ( !link1 || link1->link != seg1 || link1->pos <= seg1->pos )
926           continue;
927 
928         if ( seg1->score >= dist_threshold )
929           continue;
930 
931         for ( seg2 = segments; seg2 < segment_limit; seg2++ )
932         {
933           if ( seg2->pos > seg1->pos || seg1 == seg2 )
934             continue;
935 
936           link2 = seg2->link;
937           if ( !link2 || link2->link != seg2 || link2->pos < link1->pos )
938             continue;
939 
940           if ( seg1->pos == seg2->pos && link1->pos == link2->pos )
941             continue;
942 
943           if ( seg2->score <= seg1->score || seg1->score * 4 <= seg2->score )
944             continue;
945 
946           /* seg2 < seg1 < link1 < link2 */
947 
948           if ( seg1->len >= seg2->len * 3 )
949           {
950             AF_Segment  seg;
951 
952 
953             for ( seg = segments; seg < segment_limit; seg++ )
954             {
955               AF_Segment  link = seg->link;
956 
957 
958               if ( link == seg2 )
959               {
960                 seg->link  = NULL;
961                 seg->serif = link1;
962               }
963               else if ( link == link2 )
964               {
965                 seg->link  = NULL;
966                 seg->serif = seg1;
967               }
968             }
969           }
970           else
971           {
972             seg1->link = link1->link = NULL;
973 
974             break;
975           }
976         }
977       }
978     }
979 
980     for ( seg1 = segments; seg1 < segment_limit; seg1++ )
981     {
982       seg2 = seg1->link;
983 
984       if ( seg2 )
985       {
986         if ( seg2->link != seg1 )
987         {
988           seg1->link = NULL;
989 
990           if ( seg2->score < dist_threshold || seg1->score < seg2->score * 4 )
991             seg1->serif = seg2->link;
992         }
993       }
994     }
995   }
996 
997 
998   static FT_Error
af_cjk_hints_compute_edges(AF_GlyphHints hints,AF_Dimension dim)999   af_cjk_hints_compute_edges( AF_GlyphHints  hints,
1000                               AF_Dimension   dim )
1001   {
1002     AF_AxisHints  axis   = &hints->axis[dim];
1003     FT_Error      error  = FT_Err_Ok;
1004     FT_Memory     memory = hints->memory;
1005     AF_CJKAxis    laxis  = &((AF_CJKMetrics)hints->metrics)->axis[dim];
1006 
1007     AF_Segment    segments      = axis->segments;
1008     AF_Segment    segment_limit = segments + axis->num_segments;
1009     AF_Segment    seg;
1010 
1011     FT_Fixed      scale;
1012     FT_Pos        edge_distance_threshold;
1013 
1014 
1015     axis->num_edges = 0;
1016 
1017     scale = ( dim == AF_DIMENSION_HORZ ) ? hints->x_scale
1018                                          : hints->y_scale;
1019 
1020     /**********************************************************************
1021      *
1022      * We begin by generating a sorted table of edges for the current
1023      * direction.  To do so, we simply scan each segment and try to find
1024      * an edge in our table that corresponds to its position.
1025      *
1026      * If no edge is found, we create and insert a new edge in the
1027      * sorted table.  Otherwise, we simply add the segment to the edge's
1028      * list which is then processed in the second step to compute the
1029      * edge's properties.
1030      *
1031      * Note that the edges table is sorted along the segment/edge
1032      * position.
1033      *
1034      */
1035 
1036     edge_distance_threshold = FT_MulFix( laxis->edge_distance_threshold,
1037                                          scale );
1038     if ( edge_distance_threshold > 64 / 4 )
1039       edge_distance_threshold = FT_DivFix( 64 / 4, scale );
1040     else
1041       edge_distance_threshold = laxis->edge_distance_threshold;
1042 
1043     for ( seg = segments; seg < segment_limit; seg++ )
1044     {
1045       AF_Edge  found = NULL;
1046       FT_Pos   best  = 0xFFFFU;
1047       FT_Int   ee;
1048 
1049 
1050       /* look for an edge corresponding to the segment */
1051       for ( ee = 0; ee < axis->num_edges; ee++ )
1052       {
1053         AF_Edge  edge = axis->edges + ee;
1054         FT_Pos   dist;
1055 
1056 
1057         if ( edge->dir != seg->dir )
1058           continue;
1059 
1060         dist = seg->pos - edge->fpos;
1061         if ( dist < 0 )
1062           dist = -dist;
1063 
1064         if ( dist < edge_distance_threshold && dist < best )
1065         {
1066           AF_Segment  link = seg->link;
1067 
1068 
1069           /* check whether all linked segments of the candidate edge */
1070           /* can make a single edge.                                 */
1071           if ( link )
1072           {
1073             AF_Segment  seg1  = edge->first;
1074             FT_Pos      dist2 = 0;
1075 
1076 
1077             do
1078             {
1079               AF_Segment  link1 = seg1->link;
1080 
1081 
1082               if ( link1 )
1083               {
1084                 dist2 = AF_SEGMENT_DIST( link, link1 );
1085                 if ( dist2 >= edge_distance_threshold )
1086                   break;
1087               }
1088 
1089             } while ( ( seg1 = seg1->edge_next ) != edge->first );
1090 
1091             if ( dist2 >= edge_distance_threshold )
1092               continue;
1093           }
1094 
1095           best  = dist;
1096           found = edge;
1097         }
1098       }
1099 
1100       if ( !found )
1101       {
1102         AF_Edge  edge;
1103 
1104 
1105         /* insert a new edge in the list and */
1106         /* sort according to the position    */
1107         error = af_axis_hints_new_edge( axis, seg->pos,
1108                                         (AF_Direction)seg->dir, 0,
1109                                         memory, &edge );
1110         if ( error )
1111           goto Exit;
1112 
1113         /* add the segment to the new edge's list */
1114         FT_ZERO( edge );
1115 
1116         edge->first    = seg;
1117         edge->last     = seg;
1118         edge->dir      = seg->dir;
1119         edge->fpos     = seg->pos;
1120         edge->opos     = FT_MulFix( seg->pos, scale );
1121         edge->pos      = edge->opos;
1122         seg->edge_next = seg;
1123       }
1124       else
1125       {
1126         /* if an edge was found, simply add the segment to the edge's */
1127         /* list                                                       */
1128         seg->edge_next         = found->first;
1129         found->last->edge_next = seg;
1130         found->last            = seg;
1131       }
1132     }
1133 
1134     /*******************************************************************
1135      *
1136      * Good, we now compute each edge's properties according to the
1137      * segments found on its position.  Basically, these are
1138      *
1139      * - the edge's main direction
1140      * - stem edge, serif edge or both (which defaults to stem then)
1141      * - rounded edge, straight or both (which defaults to straight)
1142      * - link for edge
1143      *
1144      */
1145 
1146     /* first of all, set the `edge' field in each segment -- this is */
1147     /* required in order to compute edge links                       */
1148 
1149     /*
1150      * Note that removing this loop and setting the `edge' field of each
1151      * segment directly in the code above slows down execution speed for
1152      * some reasons on platforms like the Sun.
1153      */
1154     {
1155       AF_Edge  edges      = axis->edges;
1156       AF_Edge  edge_limit = edges + axis->num_edges;
1157       AF_Edge  edge;
1158 
1159 
1160       for ( edge = edges; edge < edge_limit; edge++ )
1161       {
1162         seg = edge->first;
1163         if ( seg )
1164           do
1165           {
1166             seg->edge = edge;
1167             seg       = seg->edge_next;
1168 
1169           } while ( seg != edge->first );
1170       }
1171 
1172       /* now compute each edge properties */
1173       for ( edge = edges; edge < edge_limit; edge++ )
1174       {
1175         FT_Int  is_round    = 0;  /* does it contain round segments?    */
1176         FT_Int  is_straight = 0;  /* does it contain straight segments? */
1177 
1178 
1179         seg = edge->first;
1180         if ( !seg )
1181           goto Skip_Loop;
1182 
1183         do
1184         {
1185           FT_Bool  is_serif;
1186 
1187 
1188           /* check for roundness of segment */
1189           if ( seg->flags & AF_EDGE_ROUND )
1190             is_round++;
1191           else
1192             is_straight++;
1193 
1194           /* check for links -- if seg->serif is set, then seg->link must */
1195           /* be ignored                                                   */
1196           is_serif = FT_BOOL( seg->serif && seg->serif->edge != edge );
1197 
1198           if ( seg->link || is_serif )
1199           {
1200             AF_Edge     edge2;
1201             AF_Segment  seg2;
1202 
1203 
1204             edge2 = edge->link;
1205             seg2  = seg->link;
1206 
1207             if ( is_serif )
1208             {
1209               seg2  = seg->serif;
1210               edge2 = edge->serif;
1211             }
1212 
1213             if ( edge2 )
1214             {
1215               FT_Pos  edge_delta;
1216               FT_Pos  seg_delta;
1217 
1218 
1219               edge_delta = edge->fpos - edge2->fpos;
1220               if ( edge_delta < 0 )
1221                 edge_delta = -edge_delta;
1222 
1223               seg_delta = AF_SEGMENT_DIST( seg, seg2 );
1224 
1225               if ( seg_delta < edge_delta )
1226                 edge2 = seg2->edge;
1227             }
1228             else
1229               edge2 = seg2->edge;
1230 
1231             if ( is_serif )
1232             {
1233               edge->serif   = edge2;
1234               edge2->flags |= AF_EDGE_SERIF;
1235             }
1236             else
1237               edge->link = edge2;
1238           }
1239 
1240           seg = seg->edge_next;
1241 
1242         } while ( seg != edge->first );
1243 
1244       Skip_Loop:
1245         /* set the round/straight flags */
1246         edge->flags = AF_EDGE_NORMAL;
1247 
1248         if ( is_round > 0 && is_round >= is_straight )
1249           edge->flags |= AF_EDGE_ROUND;
1250 
1251         /* get rid of serifs if link is set                 */
1252         /* XXX: This gets rid of many unpleasant artefacts! */
1253         /*      Example: the `c' in cour.pfa at size 13     */
1254 
1255         if ( edge->serif && edge->link )
1256           edge->serif = NULL;
1257       }
1258     }
1259 
1260   Exit:
1261     return error;
1262   }
1263 
1264 
1265   /* Detect segments and edges for given dimension. */
1266 
1267   static FT_Error
af_cjk_hints_detect_features(AF_GlyphHints hints,AF_Dimension dim)1268   af_cjk_hints_detect_features( AF_GlyphHints  hints,
1269                                 AF_Dimension   dim )
1270   {
1271     FT_Error  error;
1272 
1273 
1274     error = af_cjk_hints_compute_segments( hints, dim );
1275     if ( !error )
1276     {
1277       af_cjk_hints_link_segments( hints, dim );
1278 
1279       error = af_cjk_hints_compute_edges( hints, dim );
1280     }
1281     return error;
1282   }
1283 
1284 
1285   /* Compute all edges which lie within blue zones. */
1286 
1287   static void
af_cjk_hints_compute_blue_edges(AF_GlyphHints hints,AF_CJKMetrics metrics,AF_Dimension dim)1288   af_cjk_hints_compute_blue_edges( AF_GlyphHints  hints,
1289                                    AF_CJKMetrics  metrics,
1290                                    AF_Dimension   dim )
1291   {
1292     AF_AxisHints  axis       = &hints->axis[dim];
1293     AF_Edge       edge       = axis->edges;
1294     AF_Edge       edge_limit = edge + axis->num_edges;
1295     AF_CJKAxis    cjk        = &metrics->axis[dim];
1296     FT_Fixed      scale      = cjk->scale;
1297     FT_Pos        best_dist0;  /* initial threshold */
1298 
1299 
1300     /* compute the initial threshold as a fraction of the EM size */
1301     best_dist0 = FT_MulFix( metrics->units_per_em / 40, scale );
1302 
1303     if ( best_dist0 > 64 / 2 ) /* maximum 1/2 pixel */
1304       best_dist0 = 64 / 2;
1305 
1306     /* compute which blue zones are active, i.e. have their scaled */
1307     /* size < 3/4 pixels                                           */
1308 
1309     /* If the distant between an edge and a blue zone is shorter than */
1310     /* best_dist0, set the blue zone for the edge.  Then search for   */
1311     /* the blue zone with the smallest best_dist to the edge.         */
1312 
1313     for ( ; edge < edge_limit; edge++ )
1314     {
1315       FT_UInt   bb;
1316       AF_Width  best_blue = NULL;
1317       FT_Pos    best_dist = best_dist0;
1318 
1319 
1320       for ( bb = 0; bb < cjk->blue_count; bb++ )
1321       {
1322         AF_CJKBlue  blue = cjk->blues + bb;
1323         FT_Bool     is_top_right_blue, is_major_dir;
1324 
1325 
1326         /* skip inactive blue zones (i.e., those that are too small) */
1327         if ( !( blue->flags & AF_CJK_BLUE_ACTIVE ) )
1328           continue;
1329 
1330         /* if it is a top zone, check for right edges -- if it is a bottom */
1331         /* zone, check for left edges                                      */
1332         /*                                                                 */
1333         /* of course, that's for TrueType                                  */
1334         is_top_right_blue =
1335           (FT_Byte)( ( blue->flags & AF_CJK_BLUE_TOP ) != 0 );
1336         is_major_dir =
1337           FT_BOOL( edge->dir == axis->major_dir );
1338 
1339         /* if it is a top zone, the edge must be against the major    */
1340         /* direction; if it is a bottom zone, it must be in the major */
1341         /* direction                                                  */
1342         if ( is_top_right_blue ^ is_major_dir )
1343         {
1344           FT_Pos    dist;
1345           AF_Width  compare;
1346 
1347 
1348           /* Compare the edge to the closest blue zone type */
1349           if ( FT_ABS( edge->fpos - blue->ref.org ) >
1350                FT_ABS( edge->fpos - blue->shoot.org ) )
1351             compare = &blue->shoot;
1352           else
1353             compare = &blue->ref;
1354 
1355           dist = edge->fpos - compare->org;
1356           if ( dist < 0 )
1357             dist = -dist;
1358 
1359           dist = FT_MulFix( dist, scale );
1360           if ( dist < best_dist )
1361           {
1362             best_dist = dist;
1363             best_blue = compare;
1364           }
1365         }
1366       }
1367 
1368       if ( best_blue )
1369         edge->blue_edge = best_blue;
1370     }
1371   }
1372 
1373 
1374   /* Initalize hinting engine. */
1375 
1376   FT_LOCAL_DEF( FT_Error )
af_cjk_hints_init(AF_GlyphHints hints,AF_CJKMetrics metrics)1377   af_cjk_hints_init( AF_GlyphHints  hints,
1378                      AF_CJKMetrics  metrics )
1379   {
1380     FT_Render_Mode  mode;
1381     FT_UInt32       scaler_flags, other_flags;
1382 
1383 
1384     af_glyph_hints_rescale( hints, (AF_StyleMetrics)metrics );
1385 
1386     /*
1387      * correct x_scale and y_scale when needed, since they may have
1388      * been modified af_cjk_scale_dim above
1389      */
1390     hints->x_scale = metrics->axis[AF_DIMENSION_HORZ].scale;
1391     hints->x_delta = metrics->axis[AF_DIMENSION_HORZ].delta;
1392     hints->y_scale = metrics->axis[AF_DIMENSION_VERT].scale;
1393     hints->y_delta = metrics->axis[AF_DIMENSION_VERT].delta;
1394 
1395     /* compute flags depending on render mode, etc. */
1396     mode = metrics->root.scaler.render_mode;
1397 
1398     scaler_flags = hints->scaler_flags;
1399     other_flags  = 0;
1400 
1401     /*
1402      * We snap the width of vertical stems for the monochrome and
1403      * horizontal LCD rendering targets only.
1404      */
1405     if ( mode == FT_RENDER_MODE_MONO || mode == FT_RENDER_MODE_LCD )
1406       other_flags |= AF_LATIN_HINTS_HORZ_SNAP;
1407 
1408     /*
1409      * We snap the width of horizontal stems for the monochrome and
1410      * vertical LCD rendering targets only.
1411      */
1412     if ( mode == FT_RENDER_MODE_MONO || mode == FT_RENDER_MODE_LCD_V )
1413       other_flags |= AF_LATIN_HINTS_VERT_SNAP;
1414 
1415     /*
1416      * We adjust stems to full pixels unless in `light' or `lcd' mode.
1417      */
1418     if ( mode != FT_RENDER_MODE_LIGHT && mode != FT_RENDER_MODE_LCD )
1419       other_flags |= AF_LATIN_HINTS_STEM_ADJUST;
1420 
1421     if ( mode == FT_RENDER_MODE_MONO )
1422       other_flags |= AF_LATIN_HINTS_MONO;
1423 
1424     scaler_flags |= AF_SCALER_FLAG_NO_ADVANCE;
1425 
1426     hints->scaler_flags = scaler_flags;
1427     hints->other_flags  = other_flags;
1428 
1429     return FT_Err_Ok;
1430   }
1431 
1432 
1433   /*************************************************************************/
1434   /*************************************************************************/
1435   /*****                                                               *****/
1436   /*****          C J K   G L Y P H   G R I D - F I T T I N G          *****/
1437   /*****                                                               *****/
1438   /*************************************************************************/
1439   /*************************************************************************/
1440 
1441   /* Snap a given width in scaled coordinates to one of the */
1442   /* current standard widths.                               */
1443 
1444   static FT_Pos
af_cjk_snap_width(AF_Width widths,FT_UInt count,FT_Pos width)1445   af_cjk_snap_width( AF_Width  widths,
1446                      FT_UInt   count,
1447                      FT_Pos    width )
1448   {
1449     FT_UInt  n;
1450     FT_Pos   best      = 64 + 32 + 2;
1451     FT_Pos   reference = width;
1452     FT_Pos   scaled;
1453 
1454 
1455     for ( n = 0; n < count; n++ )
1456     {
1457       FT_Pos  w;
1458       FT_Pos  dist;
1459 
1460 
1461       w = widths[n].cur;
1462       dist = width - w;
1463       if ( dist < 0 )
1464         dist = -dist;
1465       if ( dist < best )
1466       {
1467         best      = dist;
1468         reference = w;
1469       }
1470     }
1471 
1472     scaled = FT_PIX_ROUND( reference );
1473 
1474     if ( width >= reference )
1475     {
1476       if ( width < scaled + 48 )
1477         width = reference;
1478     }
1479     else
1480     {
1481       if ( width > scaled - 48 )
1482         width = reference;
1483     }
1484 
1485     return width;
1486   }
1487 
1488 
1489   /* Compute the snapped width of a given stem.                          */
1490   /* There is a lot of voodoo in this function; changing the hard-coded  */
1491   /* parameters influence the whole hinting process.                     */
1492 
1493   static FT_Pos
af_cjk_compute_stem_width(AF_GlyphHints hints,AF_Dimension dim,FT_Pos width,FT_UInt base_flags,FT_UInt stem_flags)1494   af_cjk_compute_stem_width( AF_GlyphHints  hints,
1495                              AF_Dimension   dim,
1496                              FT_Pos         width,
1497                              FT_UInt        base_flags,
1498                              FT_UInt        stem_flags )
1499   {
1500     AF_CJKMetrics  metrics  = (AF_CJKMetrics)hints->metrics;
1501     AF_CJKAxis     axis     = &metrics->axis[dim];
1502     FT_Pos         dist     = width;
1503     FT_Int         sign     = 0;
1504     FT_Bool        vertical = FT_BOOL( dim == AF_DIMENSION_VERT );
1505 
1506     FT_UNUSED( base_flags );
1507     FT_UNUSED( stem_flags );
1508 
1509 
1510     if ( !AF_LATIN_HINTS_DO_STEM_ADJUST( hints ) )
1511       return width;
1512 
1513     if ( dist < 0 )
1514     {
1515       dist = -width;
1516       sign = 1;
1517     }
1518 
1519     if ( (  vertical && !AF_LATIN_HINTS_DO_VERT_SNAP( hints ) ) ||
1520          ( !vertical && !AF_LATIN_HINTS_DO_HORZ_SNAP( hints ) ) )
1521     {
1522       /* smooth hinting process: very lightly quantize the stem width */
1523 
1524       if ( axis->width_count > 0 )
1525       {
1526         if ( FT_ABS( dist - axis->widths[0].cur ) < 40 )
1527         {
1528           dist = axis->widths[0].cur;
1529           if ( dist < 48 )
1530             dist = 48;
1531 
1532           goto Done_Width;
1533         }
1534       }
1535 
1536       if ( dist < 54 )
1537         dist += ( 54 - dist ) / 2;
1538       else if ( dist < 3 * 64 )
1539       {
1540         FT_Pos  delta;
1541 
1542 
1543         delta  = dist & 63;
1544         dist  &= -64;
1545 
1546         if ( delta < 10 )
1547           dist += delta;
1548         else if ( delta < 22 )
1549           dist += 10;
1550         else if ( delta < 42 )
1551           dist += delta;
1552         else if ( delta < 54 )
1553           dist += 54;
1554         else
1555           dist += delta;
1556       }
1557     }
1558     else
1559     {
1560       /* strong hinting process: snap the stem width to integer pixels */
1561 
1562       dist = af_cjk_snap_width( axis->widths, axis->width_count, dist );
1563 
1564       if ( vertical )
1565       {
1566         /* in the case of vertical hinting, always round */
1567         /* the stem heights to integer pixels            */
1568 
1569         if ( dist >= 64 )
1570           dist = ( dist + 16 ) & ~63;
1571         else
1572           dist = 64;
1573       }
1574       else
1575       {
1576         if ( AF_LATIN_HINTS_DO_MONO( hints ) )
1577         {
1578           /* monochrome horizontal hinting: snap widths to integer pixels */
1579           /* with a different threshold                                   */
1580 
1581           if ( dist < 64 )
1582             dist = 64;
1583           else
1584             dist = ( dist + 32 ) & ~63;
1585         }
1586         else
1587         {
1588           /* for horizontal anti-aliased hinting, we adopt a more subtle */
1589           /* approach: we strengthen small stems, round stems whose size */
1590           /* is between 1 and 2 pixels to an integer, otherwise nothing  */
1591 
1592           if ( dist < 48 )
1593             dist = ( dist + 64 ) >> 1;
1594 
1595           else if ( dist < 128 )
1596             dist = ( dist + 22 ) & ~63;
1597           else
1598             /* round otherwise to prevent color fringes in LCD mode */
1599             dist = ( dist + 32 ) & ~63;
1600         }
1601       }
1602     }
1603 
1604   Done_Width:
1605     if ( sign )
1606       dist = -dist;
1607 
1608     return dist;
1609   }
1610 
1611 
1612   /* Align one stem edge relative to the previous stem edge. */
1613 
1614   static void
af_cjk_align_linked_edge(AF_GlyphHints hints,AF_Dimension dim,AF_Edge base_edge,AF_Edge stem_edge)1615   af_cjk_align_linked_edge( AF_GlyphHints  hints,
1616                             AF_Dimension   dim,
1617                             AF_Edge        base_edge,
1618                             AF_Edge        stem_edge )
1619   {
1620     FT_Pos  dist = stem_edge->opos - base_edge->opos;
1621 
1622     FT_Pos  fitted_width = af_cjk_compute_stem_width( hints, dim, dist,
1623                                                       base_edge->flags,
1624                                                       stem_edge->flags );
1625 
1626 
1627     stem_edge->pos = base_edge->pos + fitted_width;
1628 
1629     FT_TRACE5(( "  CJKLINK: edge %ld @%d (opos=%.2f) linked to %.2f,"
1630                 " dist was %.2f, now %.2f\n",
1631                 stem_edge - hints->axis[dim].edges, stem_edge->fpos,
1632                 stem_edge->opos / 64.0, stem_edge->pos / 64.0,
1633                 dist / 64.0, fitted_width / 64.0 ));
1634   }
1635 
1636 
1637   /* Shift the coordinates of the `serif' edge by the same amount */
1638   /* as the corresponding `base' edge has been moved already.     */
1639 
1640   static void
af_cjk_align_serif_edge(AF_GlyphHints hints,AF_Edge base,AF_Edge serif)1641   af_cjk_align_serif_edge( AF_GlyphHints  hints,
1642                            AF_Edge        base,
1643                            AF_Edge        serif )
1644   {
1645     FT_UNUSED( hints );
1646 
1647     serif->pos = base->pos + ( serif->opos - base->opos );
1648   }
1649 
1650 
1651   /*************************************************************************/
1652   /*************************************************************************/
1653   /*************************************************************************/
1654   /****                                                                 ****/
1655   /****                    E D G E   H I N T I N G                      ****/
1656   /****                                                                 ****/
1657   /*************************************************************************/
1658   /*************************************************************************/
1659   /*************************************************************************/
1660 
1661 
1662 #define AF_LIGHT_MODE_MAX_HORZ_GAP    9
1663 #define AF_LIGHT_MODE_MAX_VERT_GAP   15
1664 #define AF_LIGHT_MODE_MAX_DELTA_ABS  14
1665 
1666 
1667   static FT_Pos
af_hint_normal_stem(AF_GlyphHints hints,AF_Edge edge,AF_Edge edge2,FT_Pos anchor,AF_Dimension dim)1668   af_hint_normal_stem( AF_GlyphHints  hints,
1669                        AF_Edge        edge,
1670                        AF_Edge        edge2,
1671                        FT_Pos         anchor,
1672                        AF_Dimension   dim )
1673   {
1674     FT_Pos  org_len, cur_len, org_center;
1675     FT_Pos  cur_pos1, cur_pos2;
1676     FT_Pos  d_off1, u_off1, d_off2, u_off2, delta;
1677     FT_Pos  offset;
1678     FT_Pos  threshold = 64;
1679 
1680 
1681     if ( !AF_LATIN_HINTS_DO_STEM_ADJUST( hints ) )
1682     {
1683       if ( ( edge->flags  & AF_EDGE_ROUND ) &&
1684            ( edge2->flags & AF_EDGE_ROUND ) )
1685       {
1686         if ( dim == AF_DIMENSION_VERT )
1687           threshold = 64 - AF_LIGHT_MODE_MAX_HORZ_GAP;
1688         else
1689           threshold = 64 - AF_LIGHT_MODE_MAX_VERT_GAP;
1690       }
1691       else
1692       {
1693         if ( dim == AF_DIMENSION_VERT )
1694           threshold = 64 - AF_LIGHT_MODE_MAX_HORZ_GAP / 3;
1695         else
1696           threshold = 64 - AF_LIGHT_MODE_MAX_VERT_GAP / 3;
1697       }
1698     }
1699 
1700     org_len    = edge2->opos - edge->opos;
1701     cur_len    = af_cjk_compute_stem_width( hints, dim, org_len,
1702                                             edge->flags,
1703                                             edge2->flags );
1704 
1705     org_center = ( edge->opos + edge2->opos ) / 2 + anchor;
1706     cur_pos1   = org_center - cur_len / 2;
1707     cur_pos2   = cur_pos1 + cur_len;
1708     d_off1     = cur_pos1 - FT_PIX_FLOOR( cur_pos1 );
1709     d_off2     = cur_pos2 - FT_PIX_FLOOR( cur_pos2 );
1710     u_off1     = 64 - d_off1;
1711     u_off2     = 64 - d_off2;
1712     delta      = 0;
1713 
1714 
1715     if ( d_off1 == 0 || d_off2 == 0 )
1716       goto Exit;
1717 
1718     if ( cur_len <= threshold )
1719     {
1720       if ( d_off2 < cur_len )
1721       {
1722         if ( u_off1 <= d_off2 )
1723           delta =  u_off1;
1724         else
1725           delta = -d_off2;
1726       }
1727 
1728       goto Exit;
1729     }
1730 
1731     if ( threshold < 64 )
1732     {
1733       if ( d_off1 >= threshold || u_off1 >= threshold ||
1734            d_off2 >= threshold || u_off2 >= threshold )
1735         goto Exit;
1736     }
1737 
1738     offset = cur_len & 63;
1739 
1740     if ( offset < 32 )
1741     {
1742       if ( u_off1 <= offset || d_off2 <= offset )
1743         goto Exit;
1744     }
1745     else
1746       offset = 64 - threshold;
1747 
1748     d_off1 = threshold - u_off1;
1749     u_off1 = u_off1    - offset;
1750     u_off2 = threshold - d_off2;
1751     d_off2 = d_off2    - offset;
1752 
1753     if ( d_off1 <= u_off1 )
1754       u_off1 = -d_off1;
1755 
1756     if ( d_off2 <= u_off2 )
1757       u_off2 = -d_off2;
1758 
1759     if ( FT_ABS( u_off1 ) <= FT_ABS( u_off2 ) )
1760       delta = u_off1;
1761     else
1762       delta = u_off2;
1763 
1764   Exit:
1765 
1766 #if 1
1767     if ( !AF_LATIN_HINTS_DO_STEM_ADJUST( hints ) )
1768     {
1769       if ( delta > AF_LIGHT_MODE_MAX_DELTA_ABS )
1770         delta = AF_LIGHT_MODE_MAX_DELTA_ABS;
1771       else if ( delta < -AF_LIGHT_MODE_MAX_DELTA_ABS )
1772         delta = -AF_LIGHT_MODE_MAX_DELTA_ABS;
1773     }
1774 #endif
1775 
1776     cur_pos1 += delta;
1777 
1778     if ( edge->opos < edge2->opos )
1779     {
1780       edge->pos  = cur_pos1;
1781       edge2->pos = cur_pos1 + cur_len;
1782     }
1783     else
1784     {
1785       edge->pos  = cur_pos1 + cur_len;
1786       edge2->pos = cur_pos1;
1787     }
1788 
1789     return delta;
1790   }
1791 
1792 
1793   /* The main grid-fitting routine. */
1794 
1795   static void
af_cjk_hint_edges(AF_GlyphHints hints,AF_Dimension dim)1796   af_cjk_hint_edges( AF_GlyphHints  hints,
1797                      AF_Dimension   dim )
1798   {
1799     AF_AxisHints  axis       = &hints->axis[dim];
1800     AF_Edge       edges      = axis->edges;
1801     AF_Edge       edge_limit = edges + axis->num_edges;
1802     FT_PtrDist    n_edges;
1803     AF_Edge       edge;
1804     AF_Edge       anchor   = NULL;
1805     FT_Pos        delta    = 0;
1806     FT_Int        skipped  = 0;
1807     FT_Bool       has_last_stem = FALSE;
1808     FT_Pos        last_stem_pos = 0;
1809 
1810 #ifdef FT_DEBUG_LEVEL_TRACE
1811     FT_UInt       num_actions = 0;
1812 #endif
1813 
1814 
1815     FT_TRACE5(( "cjk %s edge hinting (style `%s')\n",
1816                 dim == AF_DIMENSION_VERT ? "horizontal" : "vertical",
1817                 af_style_names[hints->metrics->style_class->style] ));
1818 
1819     /* we begin by aligning all stems relative to the blue zone */
1820 
1821     if ( AF_HINTS_DO_BLUES( hints ) )
1822     {
1823       for ( edge = edges; edge < edge_limit; edge++ )
1824       {
1825         AF_Width  blue;
1826         AF_Edge   edge1, edge2;
1827 
1828 
1829         if ( edge->flags & AF_EDGE_DONE )
1830           continue;
1831 
1832         blue  = edge->blue_edge;
1833         edge1 = NULL;
1834         edge2 = edge->link;
1835 
1836         if ( blue )
1837         {
1838           edge1 = edge;
1839         }
1840         else if ( edge2 && edge2->blue_edge )
1841         {
1842           blue  = edge2->blue_edge;
1843           edge1 = edge2;
1844           edge2 = edge;
1845         }
1846 
1847         if ( !edge1 )
1848           continue;
1849 
1850 #ifdef FT_DEBUG_LEVEL_TRACE
1851         FT_TRACE5(( "  CJKBLUE: edge %ld @%d (opos=%.2f) snapped to %.2f,"
1852                     " was %.2f\n",
1853                     edge1 - edges, edge1->fpos, edge1->opos / 64.0,
1854                     blue->fit / 64.0, edge1->pos / 64.0 ));
1855 
1856         num_actions++;
1857 #endif
1858 
1859         edge1->pos    = blue->fit;
1860         edge1->flags |= AF_EDGE_DONE;
1861 
1862         if ( edge2 && !edge2->blue_edge )
1863         {
1864           af_cjk_align_linked_edge( hints, dim, edge1, edge2 );
1865           edge2->flags |= AF_EDGE_DONE;
1866 
1867 #ifdef FT_DEBUG_LEVEL_TRACE
1868           num_actions++;
1869 #endif
1870         }
1871 
1872         if ( !anchor )
1873           anchor = edge;
1874       }
1875     }
1876 
1877     /* now we align all stem edges. */
1878     for ( edge = edges; edge < edge_limit; edge++ )
1879     {
1880       AF_Edge  edge2;
1881 
1882 
1883       if ( edge->flags & AF_EDGE_DONE )
1884         continue;
1885 
1886       /* skip all non-stem edges */
1887       edge2 = edge->link;
1888       if ( !edge2 )
1889       {
1890         skipped++;
1891         continue;
1892       }
1893 
1894       /* Some CJK characters have so many stems that
1895        * the hinter is likely to merge two adjacent ones.
1896        * To solve this problem, if either edge of a stem
1897        * is too close to the previous one, we avoid
1898        * aligning the two edges, but rather interpolate
1899        * their locations at the end of this function in
1900        * order to preserve the space between the stems.
1901        */
1902       if ( has_last_stem                       &&
1903            ( edge->pos  < last_stem_pos + 64 ||
1904              edge2->pos < last_stem_pos + 64 ) )
1905       {
1906         skipped++;
1907         continue;
1908       }
1909 
1910       /* now align the stem */
1911 
1912       /* this should not happen, but it's better to be safe */
1913       if ( edge2->blue_edge )
1914       {
1915         FT_TRACE5(( "ASSERTION FAILED for edge %ld\n", edge2-edges ));
1916 
1917         af_cjk_align_linked_edge( hints, dim, edge2, edge );
1918         edge->flags |= AF_EDGE_DONE;
1919 
1920 #ifdef FT_DEBUG_LEVEL_TRACE
1921         num_actions++;
1922 #endif
1923 
1924         continue;
1925       }
1926 
1927       if ( edge2 < edge )
1928       {
1929         af_cjk_align_linked_edge( hints, dim, edge2, edge );
1930         edge->flags |= AF_EDGE_DONE;
1931 
1932 #ifdef FT_DEBUG_LEVEL_TRACE
1933         num_actions++;
1934 #endif
1935 
1936         /* We rarely reaches here it seems;
1937          * usually the two edges belonging
1938          * to one stem are marked as DONE together
1939          */
1940         has_last_stem = TRUE;
1941         last_stem_pos = edge->pos;
1942         continue;
1943       }
1944 
1945       if ( dim != AF_DIMENSION_VERT && !anchor )
1946       {
1947 
1948 #if 0
1949         if ( fixedpitch )
1950         {
1951           AF_Edge     left  = edge;
1952           AF_Edge     right = edge_limit - 1;
1953           AF_EdgeRec  left1, left2, right1, right2;
1954           FT_Pos      target, center1, center2;
1955           FT_Pos      delta1, delta2, d1, d2;
1956 
1957 
1958           while ( right > left && !right->link )
1959             right--;
1960 
1961           left1  = *left;
1962           left2  = *left->link;
1963           right1 = *right->link;
1964           right2 = *right;
1965 
1966           delta  = ( ( ( hinter->pp2.x + 32 ) & -64 ) - hinter->pp2.x ) / 2;
1967           target = left->opos + ( right->opos - left->opos ) / 2 + delta - 16;
1968 
1969           delta1  = delta;
1970           delta1 += af_hint_normal_stem( hints, left, left->link,
1971                                          delta1, 0 );
1972 
1973           if ( left->link != right )
1974             af_hint_normal_stem( hints, right->link, right, delta1, 0 );
1975 
1976           center1 = left->pos + ( right->pos - left->pos ) / 2;
1977 
1978           if ( center1 >= target )
1979             delta2 = delta - 32;
1980           else
1981             delta2 = delta + 32;
1982 
1983           delta2 += af_hint_normal_stem( hints, &left1, &left2, delta2, 0 );
1984 
1985           if ( delta1 != delta2 )
1986           {
1987             if ( left->link != right )
1988               af_hint_normal_stem( hints, &right1, &right2, delta2, 0 );
1989 
1990             center2 = left1.pos + ( right2.pos - left1.pos ) / 2;
1991 
1992             d1 = center1 - target;
1993             d2 = center2 - target;
1994 
1995             if ( FT_ABS( d2 ) < FT_ABS( d1 ) )
1996             {
1997               left->pos       = left1.pos;
1998               left->link->pos = left2.pos;
1999 
2000               if ( left->link != right )
2001               {
2002                 right->link->pos = right1.pos;
2003                 right->pos       = right2.pos;
2004               }
2005 
2006               delta1 = delta2;
2007             }
2008           }
2009 
2010           delta               = delta1;
2011           right->link->flags |= AF_EDGE_DONE;
2012           right->flags       |= AF_EDGE_DONE;
2013         }
2014         else
2015 
2016 #endif /* 0 */
2017 
2018           delta = af_hint_normal_stem( hints, edge, edge2, 0,
2019                                        AF_DIMENSION_HORZ );
2020       }
2021       else
2022         af_hint_normal_stem( hints, edge, edge2, delta, dim );
2023 
2024 #if 0
2025       printf( "stem (%d,%d) adjusted (%.1f,%.1f)\n",
2026                edge - edges, edge2 - edges,
2027                ( edge->pos - edge->opos ) / 64.0,
2028                ( edge2->pos - edge2->opos ) / 64.0 );
2029 #endif
2030 
2031       anchor = edge;
2032       edge->flags  |= AF_EDGE_DONE;
2033       edge2->flags |= AF_EDGE_DONE;
2034       has_last_stem = TRUE;
2035       last_stem_pos = edge2->pos;
2036     }
2037 
2038     /* make sure that lowercase m's maintain their symmetry */
2039 
2040     /* In general, lowercase m's have six vertical edges if they are sans */
2041     /* serif, or twelve if they are with serifs.  This implementation is  */
2042     /* based on that assumption, and seems to work very well with most    */
2043     /* faces.  However, if for a certain face this assumption is not      */
2044     /* true, the m is just rendered like before.  In addition, any stem   */
2045     /* correction will only be applied to symmetrical glyphs (even if the */
2046     /* glyph is not an m), so the potential for unwanted distortion is    */
2047     /* relatively low.                                                    */
2048 
2049     /* We don't handle horizontal edges since we can't easily assure that */
2050     /* the third (lowest) stem aligns with the base line; it might end up */
2051     /* one pixel higher or lower.                                         */
2052 
2053     n_edges = edge_limit - edges;
2054     if ( dim == AF_DIMENSION_HORZ && ( n_edges == 6 || n_edges == 12 ) )
2055     {
2056       AF_Edge  edge1, edge2, edge3;
2057       FT_Pos   dist1, dist2, span;
2058 
2059 
2060       if ( n_edges == 6 )
2061       {
2062         edge1 = edges;
2063         edge2 = edges + 2;
2064         edge3 = edges + 4;
2065       }
2066       else
2067       {
2068         edge1 = edges + 1;
2069         edge2 = edges + 5;
2070         edge3 = edges + 9;
2071       }
2072 
2073       dist1 = edge2->opos - edge1->opos;
2074       dist2 = edge3->opos - edge2->opos;
2075 
2076       span = dist1 - dist2;
2077       if ( span < 0 )
2078         span = -span;
2079 
2080       if ( edge1->link == edge1 + 1 &&
2081            edge2->link == edge2 + 1 &&
2082            edge3->link == edge3 + 1 && span < 8 )
2083       {
2084         delta = edge3->pos - ( 2 * edge2->pos - edge1->pos );
2085         edge3->pos -= delta;
2086         if ( edge3->link )
2087           edge3->link->pos -= delta;
2088 
2089         /* move the serifs along with the stem */
2090         if ( n_edges == 12 )
2091         {
2092           ( edges + 8 )->pos -= delta;
2093           ( edges + 11 )->pos -= delta;
2094         }
2095 
2096         edge3->flags |= AF_EDGE_DONE;
2097         if ( edge3->link )
2098           edge3->link->flags |= AF_EDGE_DONE;
2099       }
2100     }
2101 
2102     if ( !skipped )
2103       goto Exit;
2104 
2105     /*
2106      * now hint the remaining edges (serifs and single) in order
2107      * to complete our processing
2108      */
2109     for ( edge = edges; edge < edge_limit; edge++ )
2110     {
2111       if ( edge->flags & AF_EDGE_DONE )
2112         continue;
2113 
2114       if ( edge->serif )
2115       {
2116         af_cjk_align_serif_edge( hints, edge->serif, edge );
2117         edge->flags |= AF_EDGE_DONE;
2118         skipped--;
2119       }
2120     }
2121 
2122     if ( !skipped )
2123       goto Exit;
2124 
2125     for ( edge = edges; edge < edge_limit; edge++ )
2126     {
2127       AF_Edge  before, after;
2128 
2129 
2130       if ( edge->flags & AF_EDGE_DONE )
2131         continue;
2132 
2133       before = after = edge;
2134 
2135       while ( --before >= edges )
2136         if ( before->flags & AF_EDGE_DONE )
2137           break;
2138 
2139       while ( ++after < edge_limit )
2140         if ( after->flags & AF_EDGE_DONE )
2141           break;
2142 
2143       if ( before >= edges || after < edge_limit )
2144       {
2145         if ( before < edges )
2146           af_cjk_align_serif_edge( hints, after, edge );
2147         else if ( after >= edge_limit )
2148           af_cjk_align_serif_edge( hints, before, edge );
2149         else
2150         {
2151           if ( after->fpos == before->fpos )
2152             edge->pos = before->pos;
2153           else
2154             edge->pos = before->pos +
2155                         FT_MulDiv( edge->fpos - before->fpos,
2156                                    after->pos - before->pos,
2157                                    after->fpos - before->fpos );
2158         }
2159       }
2160     }
2161 
2162   Exit:
2163 
2164 #ifdef FT_DEBUG_LEVEL_TRACE
2165     if ( !num_actions )
2166       FT_TRACE5(( "  (none)\n" ));
2167     FT_TRACE5(( "\n" ));
2168 #endif
2169 
2170     return;
2171   }
2172 
2173 
2174   static void
af_cjk_align_edge_points(AF_GlyphHints hints,AF_Dimension dim)2175   af_cjk_align_edge_points( AF_GlyphHints  hints,
2176                             AF_Dimension   dim )
2177   {
2178     AF_AxisHints  axis       = & hints->axis[dim];
2179     AF_Edge       edges      = axis->edges;
2180     AF_Edge       edge_limit = edges + axis->num_edges;
2181     AF_Edge       edge;
2182     FT_Bool       snapping;
2183 
2184 
2185     snapping = FT_BOOL( ( dim == AF_DIMENSION_HORZ             &&
2186                           AF_LATIN_HINTS_DO_HORZ_SNAP( hints ) )  ||
2187                         ( dim == AF_DIMENSION_VERT             &&
2188                           AF_LATIN_HINTS_DO_VERT_SNAP( hints ) )  );
2189 
2190     for ( edge = edges; edge < edge_limit; edge++ )
2191     {
2192       /* move the points of each segment     */
2193       /* in each edge to the edge's position */
2194       AF_Segment  seg = edge->first;
2195 
2196 
2197       if ( snapping )
2198       {
2199         do
2200         {
2201           AF_Point  point = seg->first;
2202 
2203 
2204           for (;;)
2205           {
2206             if ( dim == AF_DIMENSION_HORZ )
2207             {
2208               point->x      = edge->pos;
2209               point->flags |= AF_FLAG_TOUCH_X;
2210             }
2211             else
2212             {
2213               point->y      = edge->pos;
2214               point->flags |= AF_FLAG_TOUCH_Y;
2215             }
2216 
2217             if ( point == seg->last )
2218               break;
2219 
2220             point = point->next;
2221           }
2222 
2223           seg = seg->edge_next;
2224 
2225         } while ( seg != edge->first );
2226       }
2227       else
2228       {
2229         FT_Pos  delta = edge->pos - edge->opos;
2230 
2231 
2232         do
2233         {
2234           AF_Point  point = seg->first;
2235 
2236 
2237           for (;;)
2238           {
2239             if ( dim == AF_DIMENSION_HORZ )
2240             {
2241               point->x     += delta;
2242               point->flags |= AF_FLAG_TOUCH_X;
2243             }
2244             else
2245             {
2246               point->y     += delta;
2247               point->flags |= AF_FLAG_TOUCH_Y;
2248             }
2249 
2250             if ( point == seg->last )
2251               break;
2252 
2253             point = point->next;
2254           }
2255 
2256           seg = seg->edge_next;
2257 
2258         } while ( seg != edge->first );
2259       }
2260     }
2261   }
2262 
2263 
2264   /* Apply the complete hinting algorithm to a CJK glyph. */
2265 
2266   FT_LOCAL_DEF( FT_Error )
af_cjk_hints_apply(FT_UInt glyph_index,AF_GlyphHints hints,FT_Outline * outline,AF_CJKMetrics metrics)2267   af_cjk_hints_apply( FT_UInt        glyph_index,
2268                       AF_GlyphHints  hints,
2269                       FT_Outline*    outline,
2270                       AF_CJKMetrics  metrics )
2271   {
2272     FT_Error  error;
2273     int       dim;
2274 
2275     FT_UNUSED( metrics );
2276     FT_UNUSED( glyph_index );
2277 
2278 
2279     error = af_glyph_hints_reload( hints, outline );
2280     if ( error )
2281       goto Exit;
2282 
2283     /* analyze glyph outline */
2284     if ( AF_HINTS_DO_HORIZONTAL( hints ) )
2285     {
2286       error = af_cjk_hints_detect_features( hints, AF_DIMENSION_HORZ );
2287       if ( error )
2288         goto Exit;
2289 
2290       af_cjk_hints_compute_blue_edges( hints, metrics, AF_DIMENSION_HORZ );
2291     }
2292 
2293     if ( AF_HINTS_DO_VERTICAL( hints ) )
2294     {
2295       error = af_cjk_hints_detect_features( hints, AF_DIMENSION_VERT );
2296       if ( error )
2297         goto Exit;
2298 
2299       af_cjk_hints_compute_blue_edges( hints, metrics, AF_DIMENSION_VERT );
2300     }
2301 
2302     /* grid-fit the outline */
2303     for ( dim = 0; dim < AF_DIMENSION_MAX; dim++ )
2304     {
2305       if ( ( dim == AF_DIMENSION_HORZ && AF_HINTS_DO_HORIZONTAL( hints ) ) ||
2306            ( dim == AF_DIMENSION_VERT && AF_HINTS_DO_VERTICAL( hints ) )   )
2307       {
2308         af_cjk_hint_edges( hints, (AF_Dimension)dim );
2309         af_cjk_align_edge_points( hints, (AF_Dimension)dim );
2310         af_glyph_hints_align_strong_points( hints, (AF_Dimension)dim );
2311         af_glyph_hints_align_weak_points( hints, (AF_Dimension)dim );
2312       }
2313     }
2314 
2315     af_glyph_hints_save( hints, outline );
2316 
2317   Exit:
2318     return error;
2319   }
2320 
2321 
2322   /*************************************************************************/
2323   /*************************************************************************/
2324   /*****                                                               *****/
2325   /*****                C J K   S C R I P T   C L A S S                *****/
2326   /*****                                                               *****/
2327   /*************************************************************************/
2328   /*************************************************************************/
2329 
2330 
2331   AF_DEFINE_WRITING_SYSTEM_CLASS(
2332     af_cjk_writing_system_class,
2333 
2334     AF_WRITING_SYSTEM_CJK,
2335 
2336     sizeof ( AF_CJKMetricsRec ),
2337 
2338     (AF_WritingSystem_InitMetricsFunc) af_cjk_metrics_init,        /* style_metrics_init    */
2339     (AF_WritingSystem_ScaleMetricsFunc)af_cjk_metrics_scale,       /* style_metrics_scale   */
2340     (AF_WritingSystem_DoneMetricsFunc) NULL,                       /* style_metrics_done    */
2341     (AF_WritingSystem_GetStdWidthsFunc)af_cjk_get_standard_widths, /* style_metrics_getstdw */
2342 
2343     (AF_WritingSystem_InitHintsFunc)   af_cjk_hints_init,          /* style_hints_init      */
2344     (AF_WritingSystem_ApplyHintsFunc)  af_cjk_hints_apply          /* style_hints_apply     */
2345   )
2346 
2347 
2348 #else /* !AF_CONFIG_OPTION_CJK */
2349 
2350 
2351   AF_DEFINE_WRITING_SYSTEM_CLASS(
2352     af_cjk_writing_system_class,
2353 
2354     AF_WRITING_SYSTEM_CJK,
2355 
2356     sizeof ( AF_CJKMetricsRec ),
2357 
2358     (AF_WritingSystem_InitMetricsFunc) NULL, /* style_metrics_init    */
2359     (AF_WritingSystem_ScaleMetricsFunc)NULL, /* style_metrics_scale   */
2360     (AF_WritingSystem_DoneMetricsFunc) NULL, /* style_metrics_done    */
2361     (AF_WritingSystem_GetStdWidthsFunc)NULL, /* style_metrics_getstdw */
2362 
2363     (AF_WritingSystem_InitHintsFunc)   NULL, /* style_hints_init      */
2364     (AF_WritingSystem_ApplyHintsFunc)  NULL  /* style_hints_apply     */
2365   )
2366 
2367 
2368 #endif /* !AF_CONFIG_OPTION_CJK */
2369 
2370 
2371 /* END */
2372