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1 /****************************************************************************
2  *
3  * ftoutln.c
4  *
5  *   FreeType outline management (body).
6  *
7  * Copyright (C) 1996-2020 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 <freetype/ftoutln.h>
20 #include <freetype/internal/ftobjs.h>
21 #include <freetype/internal/ftcalc.h>
22 #include <freetype/internal/ftdebug.h>
23 #include <freetype/fttrigon.h>
24 
25 
26   /**************************************************************************
27    *
28    * The macro FT_COMPONENT is used in trace mode.  It is an implicit
29    * parameter of the FT_TRACE() and FT_ERROR() macros, used to print/log
30    * messages during execution.
31    */
32 #undef  FT_COMPONENT
33 #define FT_COMPONENT  outline
34 
35 
36   static
37   const FT_Outline  null_outline = { 0, 0, NULL, NULL, NULL, 0 };
38 
39 
40   /* documentation is in ftoutln.h */
41 
42   FT_EXPORT_DEF( FT_Error )
FT_Outline_Decompose(FT_Outline * outline,const FT_Outline_Funcs * func_interface,void * user)43   FT_Outline_Decompose( FT_Outline*              outline,
44                         const FT_Outline_Funcs*  func_interface,
45                         void*                    user )
46   {
47 #undef  SCALED
48 #define SCALED( x )  ( (x) * ( 1L << shift ) - delta )
49 
50     FT_Vector   v_last;
51     FT_Vector   v_control;
52     FT_Vector   v_start;
53 
54     FT_Vector*  point;
55     FT_Vector*  limit;
56     char*       tags;
57 
58     FT_Error    error;
59 
60     FT_Int   n;         /* index of contour in outline     */
61     FT_UInt  first;     /* index of first point in contour */
62     FT_Int   tag;       /* current point's state           */
63 
64     FT_Int   shift;
65     FT_Pos   delta;
66 
67 
68     if ( !outline )
69       return FT_THROW( Invalid_Outline );
70 
71     if ( !func_interface )
72       return FT_THROW( Invalid_Argument );
73 
74     shift = func_interface->shift;
75     delta = func_interface->delta;
76     first = 0;
77 
78     for ( n = 0; n < outline->n_contours; n++ )
79     {
80       FT_Int  last;  /* index of last point in contour */
81 
82 
83       FT_TRACE5(( "FT_Outline_Decompose: Outline %d\n", n ));
84 
85       last = outline->contours[n];
86       if ( last < 0 )
87         goto Invalid_Outline;
88       limit = outline->points + last;
89 
90       v_start   = outline->points[first];
91       v_start.x = SCALED( v_start.x );
92       v_start.y = SCALED( v_start.y );
93 
94       v_last   = outline->points[last];
95       v_last.x = SCALED( v_last.x );
96       v_last.y = SCALED( v_last.y );
97 
98       v_control = v_start;
99 
100       point = outline->points + first;
101       tags  = outline->tags   + first;
102       tag   = FT_CURVE_TAG( tags[0] );
103 
104       /* A contour cannot start with a cubic control point! */
105       if ( tag == FT_CURVE_TAG_CUBIC )
106         goto Invalid_Outline;
107 
108       /* check first point to determine origin */
109       if ( tag == FT_CURVE_TAG_CONIC )
110       {
111         /* first point is conic control.  Yes, this happens. */
112         if ( FT_CURVE_TAG( outline->tags[last] ) == FT_CURVE_TAG_ON )
113         {
114           /* start at last point if it is on the curve */
115           v_start = v_last;
116           limit--;
117         }
118         else
119         {
120           /* if both first and last points are conic,         */
121           /* start at their middle and record its position    */
122           /* for closure                                      */
123           v_start.x = ( v_start.x + v_last.x ) / 2;
124           v_start.y = ( v_start.y + v_last.y ) / 2;
125 
126        /* v_last = v_start; */
127         }
128         point--;
129         tags--;
130       }
131 
132       FT_TRACE5(( "  move to (%.2f, %.2f)\n",
133                   v_start.x / 64.0, v_start.y / 64.0 ));
134       error = func_interface->move_to( &v_start, user );
135       if ( error )
136         goto Exit;
137 
138       while ( point < limit )
139       {
140         point++;
141         tags++;
142 
143         tag = FT_CURVE_TAG( tags[0] );
144         switch ( tag )
145         {
146         case FT_CURVE_TAG_ON:  /* emit a single line_to */
147           {
148             FT_Vector  vec;
149 
150 
151             vec.x = SCALED( point->x );
152             vec.y = SCALED( point->y );
153 
154             FT_TRACE5(( "  line to (%.2f, %.2f)\n",
155                         vec.x / 64.0, vec.y / 64.0 ));
156             error = func_interface->line_to( &vec, user );
157             if ( error )
158               goto Exit;
159             continue;
160           }
161 
162         case FT_CURVE_TAG_CONIC:  /* consume conic arcs */
163           v_control.x = SCALED( point->x );
164           v_control.y = SCALED( point->y );
165 
166         Do_Conic:
167           if ( point < limit )
168           {
169             FT_Vector  vec;
170             FT_Vector  v_middle;
171 
172 
173             point++;
174             tags++;
175             tag = FT_CURVE_TAG( tags[0] );
176 
177             vec.x = SCALED( point->x );
178             vec.y = SCALED( point->y );
179 
180             if ( tag == FT_CURVE_TAG_ON )
181             {
182               FT_TRACE5(( "  conic to (%.2f, %.2f)"
183                           " with control (%.2f, %.2f)\n",
184                           vec.x / 64.0, vec.y / 64.0,
185                           v_control.x / 64.0, v_control.y / 64.0 ));
186               error = func_interface->conic_to( &v_control, &vec, user );
187               if ( error )
188                 goto Exit;
189               continue;
190             }
191 
192             if ( tag != FT_CURVE_TAG_CONIC )
193               goto Invalid_Outline;
194 
195             v_middle.x = ( v_control.x + vec.x ) / 2;
196             v_middle.y = ( v_control.y + vec.y ) / 2;
197 
198             FT_TRACE5(( "  conic to (%.2f, %.2f)"
199                         " with control (%.2f, %.2f)\n",
200                         v_middle.x / 64.0, v_middle.y / 64.0,
201                         v_control.x / 64.0, v_control.y / 64.0 ));
202             error = func_interface->conic_to( &v_control, &v_middle, user );
203             if ( error )
204               goto Exit;
205 
206             v_control = vec;
207             goto Do_Conic;
208           }
209 
210           FT_TRACE5(( "  conic to (%.2f, %.2f)"
211                       " with control (%.2f, %.2f)\n",
212                       v_start.x / 64.0, v_start.y / 64.0,
213                       v_control.x / 64.0, v_control.y / 64.0 ));
214           error = func_interface->conic_to( &v_control, &v_start, user );
215           goto Close;
216 
217         default:  /* FT_CURVE_TAG_CUBIC */
218           {
219             FT_Vector  vec1, vec2;
220 
221 
222             if ( point + 1 > limit                             ||
223                  FT_CURVE_TAG( tags[1] ) != FT_CURVE_TAG_CUBIC )
224               goto Invalid_Outline;
225 
226             point += 2;
227             tags  += 2;
228 
229             vec1.x = SCALED( point[-2].x );
230             vec1.y = SCALED( point[-2].y );
231 
232             vec2.x = SCALED( point[-1].x );
233             vec2.y = SCALED( point[-1].y );
234 
235             if ( point <= limit )
236             {
237               FT_Vector  vec;
238 
239 
240               vec.x = SCALED( point->x );
241               vec.y = SCALED( point->y );
242 
243               FT_TRACE5(( "  cubic to (%.2f, %.2f)"
244                           " with controls (%.2f, %.2f) and (%.2f, %.2f)\n",
245                           vec.x / 64.0, vec.y / 64.0,
246                           vec1.x / 64.0, vec1.y / 64.0,
247                           vec2.x / 64.0, vec2.y / 64.0 ));
248               error = func_interface->cubic_to( &vec1, &vec2, &vec, user );
249               if ( error )
250                 goto Exit;
251               continue;
252             }
253 
254             FT_TRACE5(( "  cubic to (%.2f, %.2f)"
255                         " with controls (%.2f, %.2f) and (%.2f, %.2f)\n",
256                         v_start.x / 64.0, v_start.y / 64.0,
257                         vec1.x / 64.0, vec1.y / 64.0,
258                         vec2.x / 64.0, vec2.y / 64.0 ));
259             error = func_interface->cubic_to( &vec1, &vec2, &v_start, user );
260             goto Close;
261           }
262         }
263       }
264 
265       /* close the contour with a line segment */
266       FT_TRACE5(( "  line to (%.2f, %.2f)\n",
267                   v_start.x / 64.0, v_start.y / 64.0 ));
268       error = func_interface->line_to( &v_start, user );
269 
270     Close:
271       if ( error )
272         goto Exit;
273 
274       first = (FT_UInt)last + 1;
275     }
276 
277     FT_TRACE5(( "FT_Outline_Decompose: Done\n" ));
278     return FT_Err_Ok;
279 
280   Invalid_Outline:
281     error = FT_THROW( Invalid_Outline );
282     /* fall through */
283 
284   Exit:
285     FT_TRACE5(( "FT_Outline_Decompose: Error 0x%x\n", error ));
286     return error;
287   }
288 
289 
290   /* documentation is in ftoutln.h */
291 
292   FT_EXPORT_DEF( FT_Error )
FT_Outline_New(FT_Library library,FT_UInt numPoints,FT_Int numContours,FT_Outline * anoutline)293   FT_Outline_New( FT_Library   library,
294                   FT_UInt      numPoints,
295                   FT_Int       numContours,
296                   FT_Outline  *anoutline )
297   {
298     FT_Error   error;
299     FT_Memory  memory;
300 
301 
302     if ( !library )
303       return FT_THROW( Invalid_Library_Handle );
304 
305     memory = library->memory;
306 
307     if ( !anoutline || !memory )
308       return FT_THROW( Invalid_Argument );
309 
310     *anoutline = null_outline;
311 
312     if ( numContours < 0                  ||
313          (FT_UInt)numContours > numPoints )
314       return FT_THROW( Invalid_Argument );
315 
316     if ( numPoints > FT_OUTLINE_POINTS_MAX )
317       return FT_THROW( Array_Too_Large );
318 
319     if ( FT_NEW_ARRAY( anoutline->points,   numPoints   ) ||
320          FT_NEW_ARRAY( anoutline->tags,     numPoints   ) ||
321          FT_NEW_ARRAY( anoutline->contours, numContours ) )
322       goto Fail;
323 
324     anoutline->n_points    = (FT_Short)numPoints;
325     anoutline->n_contours  = (FT_Short)numContours;
326     anoutline->flags      |= FT_OUTLINE_OWNER;
327 
328     return FT_Err_Ok;
329 
330   Fail:
331     anoutline->flags |= FT_OUTLINE_OWNER;
332     FT_Outline_Done( library, anoutline );
333 
334     return error;
335   }
336 
337 
338   /* documentation is in ftoutln.h */
339 
340   FT_EXPORT_DEF( FT_Error )
FT_Outline_Check(FT_Outline * outline)341   FT_Outline_Check( FT_Outline*  outline )
342   {
343     if ( outline )
344     {
345       FT_Int  n_points   = outline->n_points;
346       FT_Int  n_contours = outline->n_contours;
347       FT_Int  end0, end;
348       FT_Int  n;
349 
350 
351       /* empty glyph? */
352       if ( n_points == 0 && n_contours == 0 )
353         return FT_Err_Ok;
354 
355       /* check point and contour counts */
356       if ( n_points <= 0 || n_contours <= 0 )
357         goto Bad;
358 
359       end0 = end = -1;
360       for ( n = 0; n < n_contours; n++ )
361       {
362         end = outline->contours[n];
363 
364         /* note that we don't accept empty contours */
365         if ( end <= end0 || end >= n_points )
366           goto Bad;
367 
368         end0 = end;
369       }
370 
371       if ( end != n_points - 1 )
372         goto Bad;
373 
374       /* XXX: check the tags array */
375       return FT_Err_Ok;
376     }
377 
378   Bad:
379     return FT_THROW( Invalid_Argument );
380   }
381 
382 
383   /* documentation is in ftoutln.h */
384 
385   FT_EXPORT_DEF( FT_Error )
FT_Outline_Copy(const FT_Outline * source,FT_Outline * target)386   FT_Outline_Copy( const FT_Outline*  source,
387                    FT_Outline        *target )
388   {
389     FT_Int  is_owner;
390 
391 
392     if ( !source || !target )
393       return FT_THROW( Invalid_Outline );
394 
395     if ( source->n_points   != target->n_points   ||
396          source->n_contours != target->n_contours )
397       return FT_THROW( Invalid_Argument );
398 
399     if ( source == target )
400       return FT_Err_Ok;
401 
402     if ( source->n_points )
403     {
404       FT_ARRAY_COPY( target->points, source->points, source->n_points );
405       FT_ARRAY_COPY( target->tags,   source->tags,   source->n_points );
406     }
407 
408     if ( source->n_contours )
409       FT_ARRAY_COPY( target->contours, source->contours, source->n_contours );
410 
411     /* copy all flags, except the `FT_OUTLINE_OWNER' one */
412     is_owner      = target->flags & FT_OUTLINE_OWNER;
413     target->flags = source->flags;
414 
415     target->flags &= ~FT_OUTLINE_OWNER;
416     target->flags |= is_owner;
417 
418     return FT_Err_Ok;
419   }
420 
421 
422   /* documentation is in ftoutln.h */
423 
424   FT_EXPORT_DEF( FT_Error )
FT_Outline_Done(FT_Library library,FT_Outline * outline)425   FT_Outline_Done( FT_Library   library,
426                    FT_Outline*  outline )
427   {
428     FT_Memory  memory;
429 
430 
431     if ( !library )
432       return FT_THROW( Invalid_Library_Handle );
433 
434     if ( !outline )
435       return FT_THROW( Invalid_Outline );
436 
437     memory = library->memory;
438 
439     if ( !memory )
440       return FT_THROW( Invalid_Argument );
441 
442     if ( outline->flags & FT_OUTLINE_OWNER )
443     {
444       FT_FREE( outline->points   );
445       FT_FREE( outline->tags     );
446       FT_FREE( outline->contours );
447     }
448     *outline = null_outline;
449 
450     return FT_Err_Ok;
451   }
452 
453 
454   /* documentation is in ftoutln.h */
455 
456   FT_EXPORT_DEF( void )
FT_Outline_Get_CBox(const FT_Outline * outline,FT_BBox * acbox)457   FT_Outline_Get_CBox( const FT_Outline*  outline,
458                        FT_BBox           *acbox )
459   {
460     FT_Pos  xMin, yMin, xMax, yMax;
461 
462 
463     if ( outline && acbox )
464     {
465       if ( outline->n_points == 0 )
466       {
467         xMin = 0;
468         yMin = 0;
469         xMax = 0;
470         yMax = 0;
471       }
472       else
473       {
474         FT_Vector*  vec   = outline->points;
475         FT_Vector*  limit = vec + outline->n_points;
476 
477 
478         xMin = xMax = vec->x;
479         yMin = yMax = vec->y;
480         vec++;
481 
482         for ( ; vec < limit; vec++ )
483         {
484           FT_Pos  x, y;
485 
486 
487           x = vec->x;
488           if ( x < xMin ) xMin = x;
489           if ( x > xMax ) xMax = x;
490 
491           y = vec->y;
492           if ( y < yMin ) yMin = y;
493           if ( y > yMax ) yMax = y;
494         }
495       }
496       acbox->xMin = xMin;
497       acbox->xMax = xMax;
498       acbox->yMin = yMin;
499       acbox->yMax = yMax;
500     }
501   }
502 
503 
504   /* documentation is in ftoutln.h */
505 
506   FT_EXPORT_DEF( void )
FT_Outline_Translate(const FT_Outline * outline,FT_Pos xOffset,FT_Pos yOffset)507   FT_Outline_Translate( const FT_Outline*  outline,
508                         FT_Pos             xOffset,
509                         FT_Pos             yOffset )
510   {
511     FT_UShort   n;
512     FT_Vector*  vec;
513 
514 
515     if ( !outline )
516       return;
517 
518     vec = outline->points;
519 
520     for ( n = 0; n < outline->n_points; n++ )
521     {
522       vec->x = ADD_LONG( vec->x, xOffset );
523       vec->y = ADD_LONG( vec->y, yOffset );
524       vec++;
525     }
526   }
527 
528 
529   /* documentation is in ftoutln.h */
530 
531   FT_EXPORT_DEF( void )
FT_Outline_Reverse(FT_Outline * outline)532   FT_Outline_Reverse( FT_Outline*  outline )
533   {
534     FT_UShort  n;
535     FT_Int     first, last;
536 
537 
538     if ( !outline )
539       return;
540 
541     first = 0;
542 
543     for ( n = 0; n < outline->n_contours; n++ )
544     {
545       last  = outline->contours[n];
546 
547       /* reverse point table */
548       {
549         FT_Vector*  p = outline->points + first;
550         FT_Vector*  q = outline->points + last;
551         FT_Vector   swap;
552 
553 
554         while ( p < q )
555         {
556           swap = *p;
557           *p   = *q;
558           *q   = swap;
559           p++;
560           q--;
561         }
562       }
563 
564       /* reverse tags table */
565       {
566         char*  p = outline->tags + first;
567         char*  q = outline->tags + last;
568 
569 
570         while ( p < q )
571         {
572           char  swap;
573 
574 
575           swap = *p;
576           *p   = *q;
577           *q   = swap;
578           p++;
579           q--;
580         }
581       }
582 
583       first = last + 1;
584     }
585 
586     outline->flags ^= FT_OUTLINE_REVERSE_FILL;
587   }
588 
589 
590   /* documentation is in ftoutln.h */
591 
592   FT_EXPORT_DEF( FT_Error )
FT_Outline_Render(FT_Library library,FT_Outline * outline,FT_Raster_Params * params)593   FT_Outline_Render( FT_Library         library,
594                      FT_Outline*        outline,
595                      FT_Raster_Params*  params )
596   {
597     FT_Error     error;
598     FT_Renderer  renderer;
599     FT_ListNode  node;
600     FT_BBox      cbox;
601 
602 
603     if ( !library )
604       return FT_THROW( Invalid_Library_Handle );
605 
606     if ( !outline )
607       return FT_THROW( Invalid_Outline );
608 
609     if ( !params )
610       return FT_THROW( Invalid_Argument );
611 
612     FT_Outline_Get_CBox( outline, &cbox );
613     if ( cbox.xMin < -0x1000000L || cbox.yMin < -0x1000000L ||
614          cbox.xMax >  0x1000000L || cbox.yMax >  0x1000000L )
615       return FT_THROW( Invalid_Outline );
616 
617     renderer = library->cur_renderer;
618     node     = library->renderers.head;
619 
620     params->source = (void*)outline;
621 
622     /* preset clip_box for direct mode */
623     if ( params->flags & FT_RASTER_FLAG_DIRECT    &&
624          !( params->flags & FT_RASTER_FLAG_CLIP ) )
625     {
626       params->clip_box.xMin = cbox.xMin >> 6;
627       params->clip_box.yMin = cbox.yMin >> 6;
628       params->clip_box.xMax = ( cbox.xMax + 63 ) >> 6;
629       params->clip_box.yMax = ( cbox.yMax + 63 ) >> 6;
630     }
631 
632     error = FT_ERR( Cannot_Render_Glyph );
633     while ( renderer )
634     {
635       error = renderer->raster_render( renderer->raster, params );
636       if ( !error || FT_ERR_NEQ( error, Cannot_Render_Glyph ) )
637         break;
638 
639       /* FT_Err_Cannot_Render_Glyph is returned if the render mode   */
640       /* is unsupported by the current renderer for this glyph image */
641       /* format                                                      */
642 
643       /* now, look for another renderer that supports the same */
644       /* format                                                */
645       renderer = FT_Lookup_Renderer( library, FT_GLYPH_FORMAT_OUTLINE,
646                                      &node );
647     }
648 
649     return error;
650   }
651 
652 
653   /* documentation is in ftoutln.h */
654 
655   FT_EXPORT_DEF( FT_Error )
FT_Outline_Get_Bitmap(FT_Library library,FT_Outline * outline,const FT_Bitmap * abitmap)656   FT_Outline_Get_Bitmap( FT_Library        library,
657                          FT_Outline*       outline,
658                          const FT_Bitmap  *abitmap )
659   {
660     FT_Raster_Params  params;
661 
662 
663     if ( !abitmap )
664       return FT_THROW( Invalid_Argument );
665 
666     /* other checks are delayed to `FT_Outline_Render' */
667 
668     params.target = abitmap;
669     params.flags  = 0;
670 
671     if ( abitmap->pixel_mode == FT_PIXEL_MODE_GRAY  ||
672          abitmap->pixel_mode == FT_PIXEL_MODE_LCD   ||
673          abitmap->pixel_mode == FT_PIXEL_MODE_LCD_V )
674       params.flags |= FT_RASTER_FLAG_AA;
675 
676     return FT_Outline_Render( library, outline, &params );
677   }
678 
679 
680   /* documentation is in freetype.h */
681 
682   FT_EXPORT_DEF( void )
FT_Vector_Transform(FT_Vector * vector,const FT_Matrix * matrix)683   FT_Vector_Transform( FT_Vector*        vector,
684                        const FT_Matrix*  matrix )
685   {
686     FT_Pos  xz, yz;
687 
688 
689     if ( !vector || !matrix )
690       return;
691 
692     xz = FT_MulFix( vector->x, matrix->xx ) +
693          FT_MulFix( vector->y, matrix->xy );
694 
695     yz = FT_MulFix( vector->x, matrix->yx ) +
696          FT_MulFix( vector->y, matrix->yy );
697 
698     vector->x = xz;
699     vector->y = yz;
700   }
701 
702 
703   /* documentation is in ftoutln.h */
704 
705   FT_EXPORT_DEF( void )
FT_Outline_Transform(const FT_Outline * outline,const FT_Matrix * matrix)706   FT_Outline_Transform( const FT_Outline*  outline,
707                         const FT_Matrix*   matrix )
708   {
709     FT_Vector*  vec;
710     FT_Vector*  limit;
711 
712 
713     if ( !outline || !matrix || !outline->points )
714       return;
715 
716     vec   = outline->points;
717     limit = vec + outline->n_points;
718 
719     for ( ; vec < limit; vec++ )
720       FT_Vector_Transform( vec, matrix );
721   }
722 
723 
724 #if 0
725 
726 #define FT_OUTLINE_GET_CONTOUR( outline, c, first, last )  \
727   do                                                       \
728   {                                                        \
729     (first) = ( c > 0 ) ? (outline)->points +              \
730                             (outline)->contours[c - 1] + 1 \
731                         : (outline)->points;               \
732     (last) = (outline)->points + (outline)->contours[c];   \
733   } while ( 0 )
734 
735 
736   /* Is a point in some contour?                     */
737   /*                                                 */
738   /* We treat every point of the contour as if it    */
739   /* it were ON.  That is, we allow false positives, */
740   /* but disallow false negatives.  (XXX really?)    */
741   static FT_Bool
742   ft_contour_has( FT_Outline*  outline,
743                   FT_Short     c,
744                   FT_Vector*   point )
745   {
746     FT_Vector*  first;
747     FT_Vector*  last;
748     FT_Vector*  a;
749     FT_Vector*  b;
750     FT_UInt     n = 0;
751 
752 
753     FT_OUTLINE_GET_CONTOUR( outline, c, first, last );
754 
755     for ( a = first; a <= last; a++ )
756     {
757       FT_Pos  x;
758       FT_Int  intersect;
759 
760 
761       b = ( a == last ) ? first : a + 1;
762 
763       intersect = ( a->y - point->y ) ^ ( b->y - point->y );
764 
765       /* a and b are on the same side */
766       if ( intersect >= 0 )
767       {
768         if ( intersect == 0 && a->y == point->y )
769         {
770           if ( ( a->x <= point->x && b->x >= point->x ) ||
771                ( a->x >= point->x && b->x <= point->x ) )
772             return 1;
773         }
774 
775         continue;
776       }
777 
778       x = a->x + ( b->x - a->x ) * (point->y - a->y ) / ( b->y - a->y );
779 
780       if ( x < point->x )
781         n++;
782       else if ( x == point->x )
783         return 1;
784     }
785 
786     return n & 1;
787   }
788 
789 
790   static FT_Bool
791   ft_contour_enclosed( FT_Outline*  outline,
792                        FT_UShort    c )
793   {
794     FT_Vector*  first;
795     FT_Vector*  last;
796     FT_Short    i;
797 
798 
799     FT_OUTLINE_GET_CONTOUR( outline, c, first, last );
800 
801     for ( i = 0; i < outline->n_contours; i++ )
802     {
803       if ( i != c && ft_contour_has( outline, i, first ) )
804       {
805         FT_Vector*  pt;
806 
807 
808         for ( pt = first + 1; pt <= last; pt++ )
809           if ( !ft_contour_has( outline, i, pt ) )
810             return 0;
811 
812         return 1;
813       }
814     }
815 
816     return 0;
817   }
818 
819 
820   /* This version differs from the public one in that each */
821   /* part (contour not enclosed in another contour) of the */
822   /* outline is checked for orientation.  This is          */
823   /* necessary for some buggy CJK fonts.                   */
824   static FT_Orientation
825   ft_outline_get_orientation( FT_Outline*  outline )
826   {
827     FT_Short        i;
828     FT_Vector*      first;
829     FT_Vector*      last;
830     FT_Orientation  orient = FT_ORIENTATION_NONE;
831 
832 
833     first = outline->points;
834     for ( i = 0; i < outline->n_contours; i++, first = last + 1 )
835     {
836       FT_Vector*  point;
837       FT_Vector*  xmin_point;
838       FT_Pos      xmin;
839 
840 
841       last = outline->points + outline->contours[i];
842 
843       /* skip degenerate contours */
844       if ( last < first + 2 )
845         continue;
846 
847       if ( ft_contour_enclosed( outline, i ) )
848         continue;
849 
850       xmin       = first->x;
851       xmin_point = first;
852 
853       for ( point = first + 1; point <= last; point++ )
854       {
855         if ( point->x < xmin )
856         {
857           xmin       = point->x;
858           xmin_point = point;
859         }
860       }
861 
862       /* check the orientation of the contour */
863       {
864         FT_Vector*      prev;
865         FT_Vector*      next;
866         FT_Orientation  o;
867 
868 
869         prev = ( xmin_point == first ) ? last : xmin_point - 1;
870         next = ( xmin_point == last ) ? first : xmin_point + 1;
871 
872         if ( FT_Atan2( prev->x - xmin_point->x, prev->y - xmin_point->y ) >
873              FT_Atan2( next->x - xmin_point->x, next->y - xmin_point->y ) )
874           o = FT_ORIENTATION_POSTSCRIPT;
875         else
876           o = FT_ORIENTATION_TRUETYPE;
877 
878         if ( orient == FT_ORIENTATION_NONE )
879           orient = o;
880         else if ( orient != o )
881           return FT_ORIENTATION_NONE;
882       }
883     }
884 
885     return orient;
886   }
887 
888 #endif /* 0 */
889 
890 
891   /* documentation is in ftoutln.h */
892 
893   FT_EXPORT_DEF( FT_Error )
FT_Outline_Embolden(FT_Outline * outline,FT_Pos strength)894   FT_Outline_Embolden( FT_Outline*  outline,
895                        FT_Pos       strength )
896   {
897     return FT_Outline_EmboldenXY( outline, strength, strength );
898   }
899 
900 
901   /* documentation is in ftoutln.h */
902 
903   FT_EXPORT_DEF( FT_Error )
FT_Outline_EmboldenXY(FT_Outline * outline,FT_Pos xstrength,FT_Pos ystrength)904   FT_Outline_EmboldenXY( FT_Outline*  outline,
905                          FT_Pos       xstrength,
906                          FT_Pos       ystrength )
907   {
908     FT_Vector*      points;
909     FT_Int          c, first, last;
910     FT_Orientation  orientation;
911 
912 
913     if ( !outline )
914       return FT_THROW( Invalid_Outline );
915 
916     xstrength /= 2;
917     ystrength /= 2;
918     if ( xstrength == 0 && ystrength == 0 )
919       return FT_Err_Ok;
920 
921     orientation = FT_Outline_Get_Orientation( outline );
922     if ( orientation == FT_ORIENTATION_NONE )
923     {
924       if ( outline->n_contours )
925         return FT_THROW( Invalid_Argument );
926       else
927         return FT_Err_Ok;
928     }
929 
930     points = outline->points;
931 
932     first = 0;
933     for ( c = 0; c < outline->n_contours; c++ )
934     {
935       FT_Vector  in, out, anchor, shift;
936       FT_Fixed   l_in, l_out, l_anchor = 0, l, q, d;
937       FT_Int     i, j, k;
938 
939 
940       l_in = 0;
941       last = outline->contours[c];
942 
943       /* pacify compiler */
944       in.x = in.y = anchor.x = anchor.y = 0;
945 
946       /* Counter j cycles though the points; counter i advances only  */
947       /* when points are moved; anchor k marks the first moved point. */
948       for ( i = last, j = first, k = -1;
949             j != i && i != k;
950             j = j < last ? j + 1 : first )
951       {
952         if ( j != k )
953         {
954           out.x = points[j].x - points[i].x;
955           out.y = points[j].y - points[i].y;
956           l_out = (FT_Fixed)FT_Vector_NormLen( &out );
957 
958           if ( l_out == 0 )
959             continue;
960         }
961         else
962         {
963           out   = anchor;
964           l_out = l_anchor;
965         }
966 
967         if ( l_in != 0 )
968         {
969           if ( k < 0 )
970           {
971             k        = i;
972             anchor   = in;
973             l_anchor = l_in;
974           }
975 
976           d = FT_MulFix( in.x, out.x ) + FT_MulFix( in.y, out.y );
977 
978           /* shift only if turn is less than ~160 degrees */
979           if ( d > -0xF000L )
980           {
981             d = d + 0x10000L;
982 
983             /* shift components along lateral bisector in proper orientation */
984             shift.x = in.y + out.y;
985             shift.y = in.x + out.x;
986 
987             if ( orientation == FT_ORIENTATION_TRUETYPE )
988               shift.x = -shift.x;
989             else
990               shift.y = -shift.y;
991 
992             /* restrict shift magnitude to better handle collapsing segments */
993             q = FT_MulFix( out.x, in.y ) - FT_MulFix( out.y, in.x );
994             if ( orientation == FT_ORIENTATION_TRUETYPE )
995               q = -q;
996 
997             l = FT_MIN( l_in, l_out );
998 
999             /* non-strict inequalities avoid divide-by-zero when q == l == 0 */
1000             if ( FT_MulFix( xstrength, q ) <= FT_MulFix( l, d ) )
1001               shift.x = FT_MulDiv( shift.x, xstrength, d );
1002             else
1003               shift.x = FT_MulDiv( shift.x, l, q );
1004 
1005 
1006             if ( FT_MulFix( ystrength, q ) <= FT_MulFix( l, d ) )
1007               shift.y = FT_MulDiv( shift.y, ystrength, d );
1008             else
1009               shift.y = FT_MulDiv( shift.y, l, q );
1010           }
1011           else
1012             shift.x = shift.y = 0;
1013 
1014           for ( ;
1015                 i != j;
1016                 i = i < last ? i + 1 : first )
1017           {
1018             points[i].x += xstrength + shift.x;
1019             points[i].y += ystrength + shift.y;
1020           }
1021         }
1022         else
1023           i = j;
1024 
1025         in   = out;
1026         l_in = l_out;
1027       }
1028 
1029       first = last + 1;
1030     }
1031 
1032     return FT_Err_Ok;
1033   }
1034 
1035 
1036   /* documentation is in ftoutln.h */
1037 
1038   FT_EXPORT_DEF( FT_Orientation )
FT_Outline_Get_Orientation(FT_Outline * outline)1039   FT_Outline_Get_Orientation( FT_Outline*  outline )
1040   {
1041     FT_BBox     cbox = { 0, 0, 0, 0 };
1042     FT_Int      xshift, yshift;
1043     FT_Vector*  points;
1044     FT_Vector   v_prev, v_cur;
1045     FT_Int      c, n, first;
1046     FT_Pos      area = 0;
1047 
1048 
1049     if ( !outline || outline->n_points <= 0 )
1050       return FT_ORIENTATION_TRUETYPE;
1051 
1052     /* We use the nonzero winding rule to find the orientation.       */
1053     /* Since glyph outlines behave much more `regular' than arbitrary */
1054     /* cubic or quadratic curves, this test deals with the polygon    */
1055     /* only that is spanned up by the control points.                 */
1056 
1057     FT_Outline_Get_CBox( outline, &cbox );
1058 
1059     /* Handle collapsed outlines to avoid undefined FT_MSB. */
1060     if ( cbox.xMin == cbox.xMax || cbox.yMin == cbox.yMax )
1061       return FT_ORIENTATION_NONE;
1062 
1063     /* Reject values large outlines. */
1064     if ( cbox.xMin < -0x1000000L || cbox.yMin < -0x1000000L ||
1065          cbox.xMax >  0x1000000L || cbox.yMax >  0x1000000L )
1066       return FT_ORIENTATION_NONE;
1067 
1068     xshift = FT_MSB( (FT_UInt32)( FT_ABS( cbox.xMax ) |
1069                                   FT_ABS( cbox.xMin ) ) ) - 14;
1070     xshift = FT_MAX( xshift, 0 );
1071 
1072     yshift = FT_MSB( (FT_UInt32)( cbox.yMax - cbox.yMin ) ) - 14;
1073     yshift = FT_MAX( yshift, 0 );
1074 
1075     points = outline->points;
1076 
1077     first = 0;
1078     for ( c = 0; c < outline->n_contours; c++ )
1079     {
1080       FT_Int  last = outline->contours[c];
1081 
1082 
1083       v_prev.x = points[last].x >> xshift;
1084       v_prev.y = points[last].y >> yshift;
1085 
1086       for ( n = first; n <= last; n++ )
1087       {
1088         v_cur.x = points[n].x >> xshift;
1089         v_cur.y = points[n].y >> yshift;
1090 
1091         area = ADD_LONG( area,
1092                          MUL_LONG( v_cur.y - v_prev.y,
1093                                    v_cur.x + v_prev.x ) );
1094 
1095         v_prev = v_cur;
1096       }
1097 
1098       first = last + 1;
1099     }
1100 
1101     if ( area > 0 )
1102       return FT_ORIENTATION_POSTSCRIPT;
1103     else if ( area < 0 )
1104       return FT_ORIENTATION_TRUETYPE;
1105     else
1106       return FT_ORIENTATION_NONE;
1107   }
1108 
1109 
1110 /* END */
1111