1 /***************************************************************************/
2 /*                                                                         */
3 /*  ftoutln.c                                                              */
4 /*                                                                         */
5 /*    FreeType outline management (body).                                  */
6 /*                                                                         */
7 /*  Copyright 1996-2018 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   /*************************************************************************/
20   /*                                                                       */
21   /* All functions are declared in freetype.h.                             */
22   /*                                                                       */
23   /*************************************************************************/
24 
25 
26 #include <ft2build.h>
27 #include FT_OUTLINE_H
28 #include FT_INTERNAL_OBJECTS_H
29 #include FT_INTERNAL_CALC_H
30 #include FT_INTERNAL_DEBUG_H
31 #include FT_TRIGONOMETRY_H
32 
33 
34   /*************************************************************************/
35   /*                                                                       */
36   /* The macro FT_COMPONENT is used in trace mode.  It is an implicit      */
37   /* parameter of the FT_TRACE() and FT_ERROR() macros, used to print/log  */
38   /* messages during execution.                                            */
39   /*                                                                       */
40 #undef  FT_COMPONENT
41 #define FT_COMPONENT  trace_outline
42 
43 
44   static
45   const FT_Outline  null_outline = { 0, 0, NULL, NULL, NULL, 0 };
46 
47 
48   /* documentation is in ftoutln.h */
49 
50   FT_EXPORT_DEF( FT_Error )
FT_Outline_Decompose(FT_Outline * outline,const FT_Outline_Funcs * func_interface,void * user)51   FT_Outline_Decompose( FT_Outline*              outline,
52                         const FT_Outline_Funcs*  func_interface,
53                         void*                    user )
54   {
55 #undef  SCALED
56 #define SCALED( x )  ( ( (x) < 0 ? -( -(x) << shift )             \
57                                  :  (  (x) << shift ) ) - delta )
58 
59     FT_Vector   v_last;
60     FT_Vector   v_control;
61     FT_Vector   v_start;
62 
63     FT_Vector*  point;
64     FT_Vector*  limit;
65     char*       tags;
66 
67     FT_Error    error;
68 
69     FT_Int   n;         /* index of contour in outline     */
70     FT_UInt  first;     /* index of first point in contour */
71     FT_Int   tag;       /* current point's state           */
72 
73     FT_Int   shift;
74     FT_Pos   delta;
75 
76 
77     if ( !outline )
78       return FT_THROW( Invalid_Outline );
79 
80     if ( !func_interface )
81       return FT_THROW( Invalid_Argument );
82 
83     shift = func_interface->shift;
84     delta = func_interface->delta;
85     first = 0;
86 
87     for ( n = 0; n < outline->n_contours; n++ )
88     {
89       FT_Int  last;  /* index of last point in contour */
90 
91 
92       FT_TRACE5(( "FT_Outline_Decompose: Outline %d\n", n ));
93 
94       last = outline->contours[n];
95       if ( last < 0 )
96         goto Invalid_Outline;
97       limit = outline->points + last;
98 
99       v_start   = outline->points[first];
100       v_start.x = SCALED( v_start.x );
101       v_start.y = SCALED( v_start.y );
102 
103       v_last   = outline->points[last];
104       v_last.x = SCALED( v_last.x );
105       v_last.y = SCALED( v_last.y );
106 
107       v_control = v_start;
108 
109       point = outline->points + first;
110       tags  = outline->tags   + first;
111       tag   = FT_CURVE_TAG( tags[0] );
112 
113       /* A contour cannot start with a cubic control point! */
114       if ( tag == FT_CURVE_TAG_CUBIC )
115         goto Invalid_Outline;
116 
117       /* check first point to determine origin */
118       if ( tag == FT_CURVE_TAG_CONIC )
119       {
120         /* first point is conic control.  Yes, this happens. */
121         if ( FT_CURVE_TAG( outline->tags[last] ) == FT_CURVE_TAG_ON )
122         {
123           /* start at last point if it is on the curve */
124           v_start = v_last;
125           limit--;
126         }
127         else
128         {
129           /* if both first and last points are conic,         */
130           /* start at their middle and record its position    */
131           /* for closure                                      */
132           v_start.x = ( v_start.x + v_last.x ) / 2;
133           v_start.y = ( v_start.y + v_last.y ) / 2;
134 
135        /* v_last = v_start; */
136         }
137         point--;
138         tags--;
139       }
140 
141       FT_TRACE5(( "  move to (%.2f, %.2f)\n",
142                   v_start.x / 64.0, v_start.y / 64.0 ));
143       error = func_interface->move_to( &v_start, user );
144       if ( error )
145         goto Exit;
146 
147       while ( point < limit )
148       {
149         point++;
150         tags++;
151 
152         tag = FT_CURVE_TAG( tags[0] );
153         switch ( tag )
154         {
155         case FT_CURVE_TAG_ON:  /* emit a single line_to */
156           {
157             FT_Vector  vec;
158 
159 
160             vec.x = SCALED( point->x );
161             vec.y = SCALED( point->y );
162 
163             FT_TRACE5(( "  line to (%.2f, %.2f)\n",
164                         vec.x / 64.0, vec.y / 64.0 ));
165             error = func_interface->line_to( &vec, user );
166             if ( error )
167               goto Exit;
168             continue;
169           }
170 
171         case FT_CURVE_TAG_CONIC:  /* consume conic arcs */
172           v_control.x = SCALED( point->x );
173           v_control.y = SCALED( point->y );
174 
175         Do_Conic:
176           if ( point < limit )
177           {
178             FT_Vector  vec;
179             FT_Vector  v_middle;
180 
181 
182             point++;
183             tags++;
184             tag = FT_CURVE_TAG( tags[0] );
185 
186             vec.x = SCALED( point->x );
187             vec.y = SCALED( point->y );
188 
189             if ( tag == FT_CURVE_TAG_ON )
190             {
191               FT_TRACE5(( "  conic to (%.2f, %.2f)"
192                           " with control (%.2f, %.2f)\n",
193                           vec.x / 64.0, vec.y / 64.0,
194                           v_control.x / 64.0, v_control.y / 64.0 ));
195               error = func_interface->conic_to( &v_control, &vec, user );
196               if ( error )
197                 goto Exit;
198               continue;
199             }
200 
201             if ( tag != FT_CURVE_TAG_CONIC )
202               goto Invalid_Outline;
203 
204             v_middle.x = ( v_control.x + vec.x ) / 2;
205             v_middle.y = ( v_control.y + vec.y ) / 2;
206 
207             FT_TRACE5(( "  conic to (%.2f, %.2f)"
208                         " with control (%.2f, %.2f)\n",
209                         v_middle.x / 64.0, v_middle.y / 64.0,
210                         v_control.x / 64.0, v_control.y / 64.0 ));
211             error = func_interface->conic_to( &v_control, &v_middle, user );
212             if ( error )
213               goto Exit;
214 
215             v_control = vec;
216             goto Do_Conic;
217           }
218 
219           FT_TRACE5(( "  conic to (%.2f, %.2f)"
220                       " with control (%.2f, %.2f)\n",
221                       v_start.x / 64.0, v_start.y / 64.0,
222                       v_control.x / 64.0, v_control.y / 64.0 ));
223           error = func_interface->conic_to( &v_control, &v_start, user );
224           goto Close;
225 
226         default:  /* FT_CURVE_TAG_CUBIC */
227           {
228             FT_Vector  vec1, vec2;
229 
230 
231             if ( point + 1 > limit                             ||
232                  FT_CURVE_TAG( tags[1] ) != FT_CURVE_TAG_CUBIC )
233               goto Invalid_Outline;
234 
235             point += 2;
236             tags  += 2;
237 
238             vec1.x = SCALED( point[-2].x );
239             vec1.y = SCALED( point[-2].y );
240 
241             vec2.x = SCALED( point[-1].x );
242             vec2.y = SCALED( point[-1].y );
243 
244             if ( point <= limit )
245             {
246               FT_Vector  vec;
247 
248 
249               vec.x = SCALED( point->x );
250               vec.y = SCALED( point->y );
251 
252               FT_TRACE5(( "  cubic to (%.2f, %.2f)"
253                           " with controls (%.2f, %.2f) and (%.2f, %.2f)\n",
254                           vec.x / 64.0, vec.y / 64.0,
255                           vec1.x / 64.0, vec1.y / 64.0,
256                           vec2.x / 64.0, vec2.y / 64.0 ));
257               error = func_interface->cubic_to( &vec1, &vec2, &vec, user );
258               if ( error )
259                 goto Exit;
260               continue;
261             }
262 
263             FT_TRACE5(( "  cubic to (%.2f, %.2f)"
264                         " with controls (%.2f, %.2f) and (%.2f, %.2f)\n",
265                         v_start.x / 64.0, v_start.y / 64.0,
266                         vec1.x / 64.0, vec1.y / 64.0,
267                         vec2.x / 64.0, vec2.y / 64.0 ));
268             error = func_interface->cubic_to( &vec1, &vec2, &v_start, user );
269             goto Close;
270           }
271         }
272       }
273 
274       /* close the contour with a line segment */
275       FT_TRACE5(( "  line to (%.2f, %.2f)\n",
276                   v_start.x / 64.0, v_start.y / 64.0 ));
277       error = func_interface->line_to( &v_start, user );
278 
279     Close:
280       if ( error )
281         goto Exit;
282 
283       first = (FT_UInt)last + 1;
284     }
285 
286     FT_TRACE5(( "FT_Outline_Decompose: Done\n", n ));
287     return FT_Err_Ok;
288 
289   Exit:
290     FT_TRACE5(( "FT_Outline_Decompose: Error 0x%x\n", error ));
291     return error;
292 
293   Invalid_Outline:
294     return FT_THROW( Invalid_Outline );
295   }
296 
297 
298   FT_EXPORT_DEF( FT_Error )
FT_Outline_New_Internal(FT_Memory memory,FT_UInt numPoints,FT_Int numContours,FT_Outline * anoutline)299   FT_Outline_New_Internal( FT_Memory    memory,
300                            FT_UInt      numPoints,
301                            FT_Int       numContours,
302                            FT_Outline  *anoutline )
303   {
304     FT_Error  error;
305 
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_Internal( memory, anoutline );
333 
334     return error;
335   }
336 
337 
338   /* documentation is in ftoutln.h */
339 
340   FT_EXPORT_DEF( FT_Error )
FT_Outline_New(FT_Library library,FT_UInt numPoints,FT_Int numContours,FT_Outline * anoutline)341   FT_Outline_New( FT_Library   library,
342                   FT_UInt      numPoints,
343                   FT_Int       numContours,
344                   FT_Outline  *anoutline )
345   {
346     if ( !library )
347       return FT_THROW( Invalid_Library_Handle );
348 
349     return FT_Outline_New_Internal( library->memory, numPoints,
350                                     numContours, anoutline );
351   }
352 
353 
354   /* documentation is in ftoutln.h */
355 
356   FT_EXPORT_DEF( FT_Error )
FT_Outline_Check(FT_Outline * outline)357   FT_Outline_Check( FT_Outline*  outline )
358   {
359     if ( outline )
360     {
361       FT_Int  n_points   = outline->n_points;
362       FT_Int  n_contours = outline->n_contours;
363       FT_Int  end0, end;
364       FT_Int  n;
365 
366 
367       /* empty glyph? */
368       if ( n_points == 0 && n_contours == 0 )
369         return FT_Err_Ok;
370 
371       /* check point and contour counts */
372       if ( n_points <= 0 || n_contours <= 0 )
373         goto Bad;
374 
375       end0 = end = -1;
376       for ( n = 0; n < n_contours; n++ )
377       {
378         end = outline->contours[n];
379 
380         /* note that we don't accept empty contours */
381         if ( end <= end0 || end >= n_points )
382           goto Bad;
383 
384         end0 = end;
385       }
386 
387       if ( end != n_points - 1 )
388         goto Bad;
389 
390       /* XXX: check the tags array */
391       return FT_Err_Ok;
392     }
393 
394   Bad:
395     return FT_THROW( Invalid_Argument );
396   }
397 
398 
399   /* documentation is in ftoutln.h */
400 
401   FT_EXPORT_DEF( FT_Error )
FT_Outline_Copy(const FT_Outline * source,FT_Outline * target)402   FT_Outline_Copy( const FT_Outline*  source,
403                    FT_Outline        *target )
404   {
405     FT_Int  is_owner;
406 
407 
408     if ( !source || !target )
409       return FT_THROW( Invalid_Outline );
410 
411     if ( source->n_points   != target->n_points   ||
412          source->n_contours != target->n_contours )
413       return FT_THROW( Invalid_Argument );
414 
415     if ( source == target )
416       return FT_Err_Ok;
417 
418     if ( source->n_points )
419     {
420       FT_ARRAY_COPY( target->points, source->points, source->n_points );
421       FT_ARRAY_COPY( target->tags,   source->tags,   source->n_points );
422     }
423 
424     if ( source->n_contours )
425       FT_ARRAY_COPY( target->contours, source->contours, source->n_contours );
426 
427     /* copy all flags, except the `FT_OUTLINE_OWNER' one */
428     is_owner      = target->flags & FT_OUTLINE_OWNER;
429     target->flags = source->flags;
430 
431     target->flags &= ~FT_OUTLINE_OWNER;
432     target->flags |= is_owner;
433 
434     return FT_Err_Ok;
435   }
436 
437 
438   FT_EXPORT_DEF( FT_Error )
FT_Outline_Done_Internal(FT_Memory memory,FT_Outline * outline)439   FT_Outline_Done_Internal( FT_Memory    memory,
440                             FT_Outline*  outline )
441   {
442     if ( !outline )
443       return FT_THROW( Invalid_Outline );
444 
445     if ( !memory )
446       return FT_THROW( Invalid_Argument );
447 
448     if ( outline->flags & FT_OUTLINE_OWNER )
449     {
450       FT_FREE( outline->points   );
451       FT_FREE( outline->tags     );
452       FT_FREE( outline->contours );
453     }
454     *outline = null_outline;
455 
456     return FT_Err_Ok;
457   }
458 
459 
460   /* documentation is in ftoutln.h */
461 
462   FT_EXPORT_DEF( FT_Error )
FT_Outline_Done(FT_Library library,FT_Outline * outline)463   FT_Outline_Done( FT_Library   library,
464                    FT_Outline*  outline )
465   {
466     /* check for valid `outline' in FT_Outline_Done_Internal() */
467 
468     if ( !library )
469       return FT_THROW( Invalid_Library_Handle );
470 
471     return FT_Outline_Done_Internal( library->memory, outline );
472   }
473 
474 
475   /* documentation is in ftoutln.h */
476 
477   FT_EXPORT_DEF( void )
FT_Outline_Get_CBox(const FT_Outline * outline,FT_BBox * acbox)478   FT_Outline_Get_CBox( const FT_Outline*  outline,
479                        FT_BBox           *acbox )
480   {
481     FT_Pos  xMin, yMin, xMax, yMax;
482 
483 
484     if ( outline && acbox )
485     {
486       if ( outline->n_points == 0 )
487       {
488         xMin = 0;
489         yMin = 0;
490         xMax = 0;
491         yMax = 0;
492       }
493       else
494       {
495         FT_Vector*  vec   = outline->points;
496         FT_Vector*  limit = vec + outline->n_points;
497 
498 
499         xMin = xMax = vec->x;
500         yMin = yMax = vec->y;
501         vec++;
502 
503         for ( ; vec < limit; vec++ )
504         {
505           FT_Pos  x, y;
506 
507 
508           x = vec->x;
509           if ( x < xMin ) xMin = x;
510           if ( x > xMax ) xMax = x;
511 
512           y = vec->y;
513           if ( y < yMin ) yMin = y;
514           if ( y > yMax ) yMax = y;
515         }
516       }
517       acbox->xMin = xMin;
518       acbox->xMax = xMax;
519       acbox->yMin = yMin;
520       acbox->yMax = yMax;
521     }
522   }
523 
524 
525   /* documentation is in ftoutln.h */
526 
527   FT_EXPORT_DEF( void )
FT_Outline_Translate(const FT_Outline * outline,FT_Pos xOffset,FT_Pos yOffset)528   FT_Outline_Translate( const FT_Outline*  outline,
529                         FT_Pos             xOffset,
530                         FT_Pos             yOffset )
531   {
532     FT_UShort   n;
533     FT_Vector*  vec;
534 
535 
536     if ( !outline )
537       return;
538 
539     vec = outline->points;
540 
541     for ( n = 0; n < outline->n_points; n++ )
542     {
543       vec->x = ADD_LONG( vec->x, xOffset );
544       vec->y = ADD_LONG( vec->y, yOffset );
545       vec++;
546     }
547   }
548 
549 
550   /* documentation is in ftoutln.h */
551 
552   FT_EXPORT_DEF( void )
FT_Outline_Reverse(FT_Outline * outline)553   FT_Outline_Reverse( FT_Outline*  outline )
554   {
555     FT_UShort  n;
556     FT_Int     first, last;
557 
558 
559     if ( !outline )
560       return;
561 
562     first = 0;
563 
564     for ( n = 0; n < outline->n_contours; n++ )
565     {
566       last  = outline->contours[n];
567 
568       /* reverse point table */
569       {
570         FT_Vector*  p = outline->points + first;
571         FT_Vector*  q = outline->points + last;
572         FT_Vector   swap;
573 
574 
575         while ( p < q )
576         {
577           swap = *p;
578           *p   = *q;
579           *q   = swap;
580           p++;
581           q--;
582         }
583       }
584 
585       /* reverse tags table */
586       {
587         char*  p = outline->tags + first;
588         char*  q = outline->tags + last;
589 
590 
591         while ( p < q )
592         {
593           char  swap;
594 
595 
596           swap = *p;
597           *p   = *q;
598           *q   = swap;
599           p++;
600           q--;
601         }
602       }
603 
604       first = last + 1;
605     }
606 
607     outline->flags ^= FT_OUTLINE_REVERSE_FILL;
608   }
609 
610 
611   /* documentation is in ftoutln.h */
612 
613   FT_EXPORT_DEF( FT_Error )
FT_Outline_Render(FT_Library library,FT_Outline * outline,FT_Raster_Params * params)614   FT_Outline_Render( FT_Library         library,
615                      FT_Outline*        outline,
616                      FT_Raster_Params*  params )
617   {
618     FT_Error     error;
619     FT_Renderer  renderer;
620     FT_ListNode  node;
621 
622 
623     if ( !library )
624       return FT_THROW( Invalid_Library_Handle );
625 
626     if ( !outline )
627       return FT_THROW( Invalid_Outline );
628 
629     if ( !params )
630       return FT_THROW( Invalid_Argument );
631 
632     renderer = library->cur_renderer;
633     node     = library->renderers.head;
634 
635     params->source = (void*)outline;
636 
637     error = FT_ERR( Cannot_Render_Glyph );
638     while ( renderer )
639     {
640       error = renderer->raster_render( renderer->raster, params );
641       if ( !error || FT_ERR_NEQ( error, Cannot_Render_Glyph ) )
642         break;
643 
644       /* FT_Err_Cannot_Render_Glyph is returned if the render mode   */
645       /* is unsupported by the current renderer for this glyph image */
646       /* format                                                      */
647 
648       /* now, look for another renderer that supports the same */
649       /* format                                                */
650       renderer = FT_Lookup_Renderer( library, FT_GLYPH_FORMAT_OUTLINE,
651                                      &node );
652     }
653 
654     return error;
655   }
656 
657 
658   /* documentation is in ftoutln.h */
659 
660   FT_EXPORT_DEF( FT_Error )
FT_Outline_Get_Bitmap(FT_Library library,FT_Outline * outline,const FT_Bitmap * abitmap)661   FT_Outline_Get_Bitmap( FT_Library        library,
662                          FT_Outline*       outline,
663                          const FT_Bitmap  *abitmap )
664   {
665     FT_Raster_Params  params;
666 
667 
668     if ( !abitmap )
669       return FT_THROW( Invalid_Argument );
670 
671     /* other checks are delayed to `FT_Outline_Render' */
672 
673     params.target = abitmap;
674     params.flags  = 0;
675 
676     if ( abitmap->pixel_mode == FT_PIXEL_MODE_GRAY  ||
677          abitmap->pixel_mode == FT_PIXEL_MODE_LCD   ||
678          abitmap->pixel_mode == FT_PIXEL_MODE_LCD_V )
679       params.flags |= FT_RASTER_FLAG_AA;
680 
681     return FT_Outline_Render( library, outline, &params );
682   }
683 
684 
685   /* documentation is in freetype.h */
686 
687   FT_EXPORT_DEF( void )
FT_Vector_Transform(FT_Vector * vector,const FT_Matrix * matrix)688   FT_Vector_Transform( FT_Vector*        vector,
689                        const FT_Matrix*  matrix )
690   {
691     FT_Pos  xz, yz;
692 
693 
694     if ( !vector || !matrix )
695       return;
696 
697     xz = FT_MulFix( vector->x, matrix->xx ) +
698          FT_MulFix( vector->y, matrix->xy );
699 
700     yz = FT_MulFix( vector->x, matrix->yx ) +
701          FT_MulFix( vector->y, matrix->yy );
702 
703     vector->x = xz;
704     vector->y = yz;
705   }
706 
707 
708   /* documentation is in ftoutln.h */
709 
710   FT_EXPORT_DEF( void )
FT_Outline_Transform(const FT_Outline * outline,const FT_Matrix * matrix)711   FT_Outline_Transform( const FT_Outline*  outline,
712                         const FT_Matrix*   matrix )
713   {
714     FT_Vector*  vec;
715     FT_Vector*  limit;
716 
717 
718     if ( !outline || !matrix )
719       return;
720 
721     vec   = outline->points;
722     limit = vec + outline->n_points;
723 
724     for ( ; vec < limit; vec++ )
725       FT_Vector_Transform( vec, matrix );
726   }
727 
728 
729 #if 0
730 
731 #define FT_OUTLINE_GET_CONTOUR( outline, c, first, last )  \
732   do                                                       \
733   {                                                        \
734     (first) = ( c > 0 ) ? (outline)->points +              \
735                             (outline)->contours[c - 1] + 1 \
736                         : (outline)->points;               \
737     (last) = (outline)->points + (outline)->contours[c];   \
738   } while ( 0 )
739 
740 
741   /* Is a point in some contour?                     */
742   /*                                                 */
743   /* We treat every point of the contour as if it    */
744   /* it were ON.  That is, we allow false positives, */
745   /* but disallow false negatives.  (XXX really?)    */
746   static FT_Bool
747   ft_contour_has( FT_Outline*  outline,
748                   FT_Short     c,
749                   FT_Vector*   point )
750   {
751     FT_Vector*  first;
752     FT_Vector*  last;
753     FT_Vector*  a;
754     FT_Vector*  b;
755     FT_UInt     n = 0;
756 
757 
758     FT_OUTLINE_GET_CONTOUR( outline, c, first, last );
759 
760     for ( a = first; a <= last; a++ )
761     {
762       FT_Pos  x;
763       FT_Int  intersect;
764 
765 
766       b = ( a == last ) ? first : a + 1;
767 
768       intersect = ( a->y - point->y ) ^ ( b->y - point->y );
769 
770       /* a and b are on the same side */
771       if ( intersect >= 0 )
772       {
773         if ( intersect == 0 && a->y == point->y )
774         {
775           if ( ( a->x <= point->x && b->x >= point->x ) ||
776                ( a->x >= point->x && b->x <= point->x ) )
777             return 1;
778         }
779 
780         continue;
781       }
782 
783       x = a->x + ( b->x - a->x ) * (point->y - a->y ) / ( b->y - a->y );
784 
785       if ( x < point->x )
786         n++;
787       else if ( x == point->x )
788         return 1;
789     }
790 
791     return n & 1;
792   }
793 
794 
795   static FT_Bool
796   ft_contour_enclosed( FT_Outline*  outline,
797                        FT_UShort    c )
798   {
799     FT_Vector*  first;
800     FT_Vector*  last;
801     FT_Short    i;
802 
803 
804     FT_OUTLINE_GET_CONTOUR( outline, c, first, last );
805 
806     for ( i = 0; i < outline->n_contours; i++ )
807     {
808       if ( i != c && ft_contour_has( outline, i, first ) )
809       {
810         FT_Vector*  pt;
811 
812 
813         for ( pt = first + 1; pt <= last; pt++ )
814           if ( !ft_contour_has( outline, i, pt ) )
815             return 0;
816 
817         return 1;
818       }
819     }
820 
821     return 0;
822   }
823 
824 
825   /* This version differs from the public one in that each */
826   /* part (contour not enclosed in another contour) of the */
827   /* outline is checked for orientation.  This is          */
828   /* necessary for some buggy CJK fonts.                   */
829   static FT_Orientation
830   ft_outline_get_orientation( FT_Outline*  outline )
831   {
832     FT_Short        i;
833     FT_Vector*      first;
834     FT_Vector*      last;
835     FT_Orientation  orient = FT_ORIENTATION_NONE;
836 
837 
838     first = outline->points;
839     for ( i = 0; i < outline->n_contours; i++, first = last + 1 )
840     {
841       FT_Vector*  point;
842       FT_Vector*  xmin_point;
843       FT_Pos      xmin;
844 
845 
846       last = outline->points + outline->contours[i];
847 
848       /* skip degenerate contours */
849       if ( last < first + 2 )
850         continue;
851 
852       if ( ft_contour_enclosed( outline, i ) )
853         continue;
854 
855       xmin       = first->x;
856       xmin_point = first;
857 
858       for ( point = first + 1; point <= last; point++ )
859       {
860         if ( point->x < xmin )
861         {
862           xmin       = point->x;
863           xmin_point = point;
864         }
865       }
866 
867       /* check the orientation of the contour */
868       {
869         FT_Vector*      prev;
870         FT_Vector*      next;
871         FT_Orientation  o;
872 
873 
874         prev = ( xmin_point == first ) ? last : xmin_point - 1;
875         next = ( xmin_point == last ) ? first : xmin_point + 1;
876 
877         if ( FT_Atan2( prev->x - xmin_point->x, prev->y - xmin_point->y ) >
878              FT_Atan2( next->x - xmin_point->x, next->y - xmin_point->y ) )
879           o = FT_ORIENTATION_POSTSCRIPT;
880         else
881           o = FT_ORIENTATION_TRUETYPE;
882 
883         if ( orient == FT_ORIENTATION_NONE )
884           orient = o;
885         else if ( orient != o )
886           return FT_ORIENTATION_NONE;
887       }
888     }
889 
890     return orient;
891   }
892 
893 #endif /* 0 */
894 
895 
896   /* documentation is in ftoutln.h */
897 
898   FT_EXPORT_DEF( FT_Error )
FT_Outline_Embolden(FT_Outline * outline,FT_Pos strength)899   FT_Outline_Embolden( FT_Outline*  outline,
900                        FT_Pos       strength )
901   {
902     return FT_Outline_EmboldenXY( outline, strength, strength );
903   }
904 
905 
906   /* documentation is in ftoutln.h */
907 
908   FT_EXPORT_DEF( FT_Error )
FT_Outline_EmboldenXY(FT_Outline * outline,FT_Pos xstrength,FT_Pos ystrength)909   FT_Outline_EmboldenXY( FT_Outline*  outline,
910                          FT_Pos       xstrength,
911                          FT_Pos       ystrength )
912   {
913     FT_Vector*  points;
914     FT_Int      c, first, last;
915     FT_Int      orientation;
916 
917 
918     if ( !outline )
919       return FT_THROW( Invalid_Outline );
920 
921     xstrength /= 2;
922     ystrength /= 2;
923     if ( xstrength == 0 && ystrength == 0 )
924       return FT_Err_Ok;
925 
926     orientation = FT_Outline_Get_Orientation( outline );
927     if ( orientation == FT_ORIENTATION_NONE )
928     {
929       if ( outline->n_contours )
930         return FT_THROW( Invalid_Argument );
931       else
932         return FT_Err_Ok;
933     }
934 
935     points = outline->points;
936 
937     first = 0;
938     for ( c = 0; c < outline->n_contours; c++ )
939     {
940       FT_Vector  in, out, anchor, shift;
941       FT_Fixed   l_in, l_out, l_anchor = 0, l, q, d;
942       FT_Int     i, j, k;
943 
944 
945       l_in = 0;
946       last = outline->contours[c];
947 
948       /* pacify compiler */
949       in.x = in.y = anchor.x = anchor.y = 0;
950 
951       /* Counter j cycles though the points; counter i advances only  */
952       /* when points are moved; anchor k marks the first moved point. */
953       for ( i = last, j = first, k = -1;
954             j != i && i != k;
955             j = j < last ? j + 1 : first )
956       {
957         if ( j != k )
958         {
959           out.x = points[j].x - points[i].x;
960           out.y = points[j].y - points[i].y;
961           l_out = (FT_Fixed)FT_Vector_NormLen( &out );
962 
963           if ( l_out == 0 )
964             continue;
965         }
966         else
967         {
968           out   = anchor;
969           l_out = l_anchor;
970         }
971 
972         if ( l_in != 0 )
973         {
974           if ( k < 0 )
975           {
976             k        = i;
977             anchor   = in;
978             l_anchor = l_in;
979           }
980 
981           d = FT_MulFix( in.x, out.x ) + FT_MulFix( in.y, out.y );
982 
983           /* shift only if turn is less than ~160 degrees */
984           if ( d > -0xF000L )
985           {
986             d = d + 0x10000L;
987 
988             /* shift components along lateral bisector in proper orientation */
989             shift.x = in.y + out.y;
990             shift.y = in.x + out.x;
991 
992             if ( orientation == FT_ORIENTATION_TRUETYPE )
993               shift.x = -shift.x;
994             else
995               shift.y = -shift.y;
996 
997             /* restrict shift magnitude to better handle collapsing segments */
998             q = FT_MulFix( out.x, in.y ) - FT_MulFix( out.y, in.x );
999             if ( orientation == FT_ORIENTATION_TRUETYPE )
1000               q = -q;
1001 
1002             l = FT_MIN( l_in, l_out );
1003 
1004             /* non-strict inequalities avoid divide-by-zero when q == l == 0 */
1005             if ( FT_MulFix( xstrength, q ) <= FT_MulFix( l, d ) )
1006               shift.x = FT_MulDiv( shift.x, xstrength, d );
1007             else
1008               shift.x = FT_MulDiv( shift.x, l, q );
1009 
1010 
1011             if ( FT_MulFix( ystrength, q ) <= FT_MulFix( l, d ) )
1012               shift.y = FT_MulDiv( shift.y, ystrength, d );
1013             else
1014               shift.y = FT_MulDiv( shift.y, l, q );
1015           }
1016           else
1017             shift.x = shift.y = 0;
1018 
1019           for ( ;
1020                 i != j;
1021                 i = i < last ? i + 1 : first )
1022           {
1023             points[i].x += xstrength + shift.x;
1024             points[i].y += ystrength + shift.y;
1025           }
1026         }
1027         else
1028           i = j;
1029 
1030         in   = out;
1031         l_in = l_out;
1032       }
1033 
1034       first = last + 1;
1035     }
1036 
1037     return FT_Err_Ok;
1038   }
1039 
1040 
1041   /* documentation is in ftoutln.h */
1042 
1043   FT_EXPORT_DEF( FT_Orientation )
FT_Outline_Get_Orientation(FT_Outline * outline)1044   FT_Outline_Get_Orientation( FT_Outline*  outline )
1045   {
1046     FT_BBox     cbox;
1047     FT_Int      xshift, yshift;
1048     FT_Vector*  points;
1049     FT_Vector   v_prev, v_cur;
1050     FT_Int      c, n, first;
1051     FT_Pos      area = 0;
1052 
1053 
1054     if ( !outline || outline->n_points <= 0 )
1055       return FT_ORIENTATION_TRUETYPE;
1056 
1057     /* We use the nonzero winding rule to find the orientation.       */
1058     /* Since glyph outlines behave much more `regular' than arbitrary */
1059     /* cubic or quadratic curves, this test deals with the polygon    */
1060     /* only that is spanned up by the control points.                 */
1061 
1062     FT_Outline_Get_CBox( outline, &cbox );
1063 
1064     /* Handle collapsed outlines to avoid undefined FT_MSB. */
1065     if ( cbox.xMin == cbox.xMax || cbox.yMin == cbox.yMax )
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                          ( v_cur.y - v_prev.y ) * ( v_cur.x + v_prev.x ) );
1093 
1094         v_prev = v_cur;
1095       }
1096 
1097       first = last + 1;
1098     }
1099 
1100     if ( area > 0 )
1101       return FT_ORIENTATION_POSTSCRIPT;
1102     else if ( area < 0 )
1103       return FT_ORIENTATION_TRUETYPE;
1104     else
1105       return FT_ORIENTATION_NONE;
1106   }
1107 
1108 
1109 /* END */
1110