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1 /***************************************************************************/
2 /*                                                                         */
3 /*  ftgloadr.c                                                             */
4 /*                                                                         */
5 /*    The FreeType glyph loader (body).                                    */
6 /*                                                                         */
7 /*  Copyright 2002-2006, 2010, 2013 by                                     */
8 /*  David Turner, Robert Wilhelm, and Werner Lemberg                       */
9 /*                                                                         */
10 /*  This file is part of the FreeType project, and may only be used,       */
11 /*  modified, and distributed under the terms of the FreeType project      */
12 /*  license, LICENSE.TXT.  By continuing to use, modify, or distribute     */
13 /*  this file you indicate that you have read the license and              */
14 /*  understand and accept it fully.                                        */
15 /*                                                                         */
16 /***************************************************************************/
17 
18 
19 #include <ft2build.h>
20 #include FT_INTERNAL_DEBUG_H
21 #include FT_INTERNAL_GLYPH_LOADER_H
22 #include FT_INTERNAL_MEMORY_H
23 #include FT_INTERNAL_OBJECTS_H
24 
25 #undef  FT_COMPONENT
26 #define FT_COMPONENT  trace_gloader
27 
28 
29   /*************************************************************************/
30   /*************************************************************************/
31   /*************************************************************************/
32   /*****                                                               *****/
33   /*****                                                               *****/
34   /*****                    G L Y P H   L O A D E R                    *****/
35   /*****                                                               *****/
36   /*****                                                               *****/
37   /*************************************************************************/
38   /*************************************************************************/
39   /*************************************************************************/
40 
41   /*************************************************************************/
42   /*                                                                       */
43   /* The glyph loader is a simple object which is used to load a set of    */
44   /* glyphs easily.  It is critical for the correct loading of composites. */
45   /*                                                                       */
46   /* Ideally, one can see it as a stack of abstract `glyph' objects.       */
47   /*                                                                       */
48   /*   loader.base     Is really the bottom of the stack.  It describes a  */
49   /*                   single glyph image made of the juxtaposition of     */
50   /*                   several glyphs (those `in the stack').              */
51   /*                                                                       */
52   /*   loader.current  Describes the top of the stack, on which a new      */
53   /*                   glyph can be loaded.                                */
54   /*                                                                       */
55   /*   Rewind          Clears the stack.                                   */
56   /*   Prepare         Set up `loader.current' for addition of a new glyph */
57   /*                   image.                                              */
58   /*   Add             Add the `current' glyph image to the `base' one,    */
59   /*                   and prepare for another one.                        */
60   /*                                                                       */
61   /* The glyph loader is now a base object.  Each driver used to           */
62   /* re-implement it in one way or the other, which wasted code and        */
63   /* energy.                                                               */
64   /*                                                                       */
65   /*************************************************************************/
66 
67 
68   /* create a new glyph loader */
69   FT_BASE_DEF( FT_Error )
FT_GlyphLoader_New(FT_Memory memory,FT_GlyphLoader * aloader)70   FT_GlyphLoader_New( FT_Memory        memory,
71                       FT_GlyphLoader  *aloader )
72   {
73     FT_GlyphLoader  loader = NULL;
74     FT_Error        error;
75 
76 
77     if ( !FT_NEW( loader ) )
78     {
79       loader->memory = memory;
80       *aloader       = loader;
81     }
82     return error;
83   }
84 
85 
86   /* rewind the glyph loader - reset counters to 0 */
87   FT_BASE_DEF( void )
FT_GlyphLoader_Rewind(FT_GlyphLoader loader)88   FT_GlyphLoader_Rewind( FT_GlyphLoader  loader )
89   {
90     FT_GlyphLoad  base    = &loader->base;
91     FT_GlyphLoad  current = &loader->current;
92 
93 
94     base->outline.n_points   = 0;
95     base->outline.n_contours = 0;
96     base->num_subglyphs      = 0;
97 
98     *current = *base;
99   }
100 
101 
102   /* reset the glyph loader, frees all allocated tables */
103   /* and starts from zero                               */
104   FT_BASE_DEF( void )
FT_GlyphLoader_Reset(FT_GlyphLoader loader)105   FT_GlyphLoader_Reset( FT_GlyphLoader  loader )
106   {
107     FT_Memory memory = loader->memory;
108 
109 
110     FT_FREE( loader->base.outline.points );
111     FT_FREE( loader->base.outline.tags );
112     FT_FREE( loader->base.outline.contours );
113     FT_FREE( loader->base.extra_points );
114     FT_FREE( loader->base.subglyphs );
115 
116     loader->base.extra_points2 = NULL;
117 
118     loader->max_points    = 0;
119     loader->max_contours  = 0;
120     loader->max_subglyphs = 0;
121 
122     FT_GlyphLoader_Rewind( loader );
123   }
124 
125 
126   /* delete a glyph loader */
127   FT_BASE_DEF( void )
FT_GlyphLoader_Done(FT_GlyphLoader loader)128   FT_GlyphLoader_Done( FT_GlyphLoader  loader )
129   {
130     if ( loader )
131     {
132       FT_Memory memory = loader->memory;
133 
134 
135       FT_GlyphLoader_Reset( loader );
136       FT_FREE( loader );
137     }
138   }
139 
140 
141   /* re-adjust the `current' outline fields */
142   static void
FT_GlyphLoader_Adjust_Points(FT_GlyphLoader loader)143   FT_GlyphLoader_Adjust_Points( FT_GlyphLoader  loader )
144   {
145     FT_Outline*  base    = &loader->base.outline;
146     FT_Outline*  current = &loader->current.outline;
147 
148 
149     current->points   = base->points   + base->n_points;
150     current->tags     = base->tags     + base->n_points;
151     current->contours = base->contours + base->n_contours;
152 
153     /* handle extra points table - if any */
154     if ( loader->use_extra )
155     {
156       loader->current.extra_points  = loader->base.extra_points +
157                                       base->n_points;
158 
159       loader->current.extra_points2 = loader->base.extra_points2 +
160                                       base->n_points;
161     }
162   }
163 
164 
165   FT_BASE_DEF( FT_Error )
FT_GlyphLoader_CreateExtra(FT_GlyphLoader loader)166   FT_GlyphLoader_CreateExtra( FT_GlyphLoader  loader )
167   {
168     FT_Error   error;
169     FT_Memory  memory = loader->memory;
170 
171 
172     if ( !FT_NEW_ARRAY( loader->base.extra_points, 2 * loader->max_points ) )
173     {
174       loader->use_extra          = 1;
175       loader->base.extra_points2 = loader->base.extra_points +
176                                    loader->max_points;
177 
178       FT_GlyphLoader_Adjust_Points( loader );
179     }
180     return error;
181   }
182 
183 
184   /* re-adjust the `current' subglyphs field */
185   static void
FT_GlyphLoader_Adjust_Subglyphs(FT_GlyphLoader loader)186   FT_GlyphLoader_Adjust_Subglyphs( FT_GlyphLoader  loader )
187   {
188     FT_GlyphLoad  base    = &loader->base;
189     FT_GlyphLoad  current = &loader->current;
190 
191 
192     current->subglyphs = base->subglyphs + base->num_subglyphs;
193   }
194 
195 
196   /* Ensure that we can add `n_points' and `n_contours' to our glyph.      */
197   /* This function reallocates its outline tables if necessary.  Note that */
198   /* it DOESN'T change the number of points within the loader!             */
199   /*                                                                       */
200   FT_BASE_DEF( FT_Error )
FT_GlyphLoader_CheckPoints(FT_GlyphLoader loader,FT_UInt n_points,FT_UInt n_contours)201   FT_GlyphLoader_CheckPoints( FT_GlyphLoader  loader,
202                               FT_UInt         n_points,
203                               FT_UInt         n_contours )
204   {
205     FT_Memory    memory  = loader->memory;
206     FT_Error     error   = FT_Err_Ok;
207     FT_Outline*  base    = &loader->base.outline;
208     FT_Outline*  current = &loader->current.outline;
209     FT_Bool      adjust  = 0;
210 
211     FT_UInt      new_max, old_max;
212 
213 
214     /* check points & tags */
215     new_max = base->n_points + current->n_points + n_points;
216     old_max = loader->max_points;
217 
218     if ( new_max > old_max )
219     {
220       new_max = FT_PAD_CEIL( new_max, 8 );
221 
222       if ( new_max > FT_OUTLINE_POINTS_MAX )
223         return FT_THROW( Array_Too_Large );
224 
225       if ( FT_RENEW_ARRAY( base->points, old_max, new_max ) ||
226            FT_RENEW_ARRAY( base->tags,   old_max, new_max ) )
227         goto Exit;
228 
229       if ( loader->use_extra )
230       {
231         if ( FT_RENEW_ARRAY( loader->base.extra_points,
232                              old_max * 2, new_max * 2 ) )
233           goto Exit;
234 
235         FT_ARRAY_MOVE( loader->base.extra_points + new_max,
236                        loader->base.extra_points + old_max,
237                        old_max );
238 
239         loader->base.extra_points2 = loader->base.extra_points + new_max;
240       }
241 
242       adjust = 1;
243       loader->max_points = new_max;
244     }
245 
246     /* check contours */
247     old_max = loader->max_contours;
248     new_max = base->n_contours + current->n_contours +
249               n_contours;
250     if ( new_max > old_max )
251     {
252       new_max = FT_PAD_CEIL( new_max, 4 );
253 
254       if ( new_max > FT_OUTLINE_CONTOURS_MAX )
255         return FT_THROW( Array_Too_Large );
256 
257       if ( FT_RENEW_ARRAY( base->contours, old_max, new_max ) )
258         goto Exit;
259 
260       adjust = 1;
261       loader->max_contours = new_max;
262     }
263 
264     if ( adjust )
265       FT_GlyphLoader_Adjust_Points( loader );
266 
267   Exit:
268     return error;
269   }
270 
271 
272   /* Ensure that we can add `n_subglyphs' to our glyph. this function */
273   /* reallocates its subglyphs table if necessary.  Note that it DOES */
274   /* NOT change the number of subglyphs within the loader!            */
275   /*                                                                  */
276   FT_BASE_DEF( FT_Error )
FT_GlyphLoader_CheckSubGlyphs(FT_GlyphLoader loader,FT_UInt n_subs)277   FT_GlyphLoader_CheckSubGlyphs( FT_GlyphLoader  loader,
278                                  FT_UInt         n_subs )
279   {
280     FT_Memory     memory = loader->memory;
281     FT_Error      error  = FT_Err_Ok;
282     FT_UInt       new_max, old_max;
283 
284     FT_GlyphLoad  base    = &loader->base;
285     FT_GlyphLoad  current = &loader->current;
286 
287 
288     new_max = base->num_subglyphs + current->num_subglyphs + n_subs;
289     old_max = loader->max_subglyphs;
290     if ( new_max > old_max )
291     {
292       new_max = FT_PAD_CEIL( new_max, 2 );
293       if ( FT_RENEW_ARRAY( base->subglyphs, old_max, new_max ) )
294         goto Exit;
295 
296       loader->max_subglyphs = new_max;
297 
298       FT_GlyphLoader_Adjust_Subglyphs( loader );
299     }
300 
301   Exit:
302     return error;
303   }
304 
305 
306   /* prepare loader for the addition of a new glyph on top of the base one */
307   FT_BASE_DEF( void )
FT_GlyphLoader_Prepare(FT_GlyphLoader loader)308   FT_GlyphLoader_Prepare( FT_GlyphLoader  loader )
309   {
310     FT_GlyphLoad  current = &loader->current;
311 
312 
313     current->outline.n_points   = 0;
314     current->outline.n_contours = 0;
315     current->num_subglyphs      = 0;
316 
317     FT_GlyphLoader_Adjust_Points   ( loader );
318     FT_GlyphLoader_Adjust_Subglyphs( loader );
319   }
320 
321 
322   /* add current glyph to the base image -- and prepare for another */
323   FT_BASE_DEF( void )
FT_GlyphLoader_Add(FT_GlyphLoader loader)324   FT_GlyphLoader_Add( FT_GlyphLoader  loader )
325   {
326     FT_GlyphLoad  base;
327     FT_GlyphLoad  current;
328 
329     FT_UInt       n_curr_contours;
330     FT_UInt       n_base_points;
331     FT_UInt       n;
332 
333 
334     if ( !loader )
335       return;
336 
337     base    = &loader->base;
338     current = &loader->current;
339 
340     n_curr_contours = current->outline.n_contours;
341     n_base_points   = base->outline.n_points;
342 
343     base->outline.n_points =
344       (short)( base->outline.n_points + current->outline.n_points );
345     base->outline.n_contours =
346       (short)( base->outline.n_contours + current->outline.n_contours );
347 
348     base->num_subglyphs += current->num_subglyphs;
349 
350     /* adjust contours count in newest outline */
351     for ( n = 0; n < n_curr_contours; n++ )
352       current->outline.contours[n] =
353         (short)( current->outline.contours[n] + n_base_points );
354 
355     /* prepare for another new glyph image */
356     FT_GlyphLoader_Prepare( loader );
357   }
358 
359 
360   FT_BASE_DEF( FT_Error )
FT_GlyphLoader_CopyPoints(FT_GlyphLoader target,FT_GlyphLoader source)361   FT_GlyphLoader_CopyPoints( FT_GlyphLoader  target,
362                              FT_GlyphLoader  source )
363   {
364     FT_Error  error;
365     FT_UInt   num_points   = source->base.outline.n_points;
366     FT_UInt   num_contours = source->base.outline.n_contours;
367 
368 
369     error = FT_GlyphLoader_CheckPoints( target, num_points, num_contours );
370     if ( !error )
371     {
372       FT_Outline*  out = &target->base.outline;
373       FT_Outline*  in  = &source->base.outline;
374 
375 
376       FT_ARRAY_COPY( out->points, in->points,
377                      num_points );
378       FT_ARRAY_COPY( out->tags, in->tags,
379                      num_points );
380       FT_ARRAY_COPY( out->contours, in->contours,
381                      num_contours );
382 
383       /* do we need to copy the extra points? */
384       if ( target->use_extra && source->use_extra )
385       {
386         FT_ARRAY_COPY( target->base.extra_points, source->base.extra_points,
387                        num_points );
388         FT_ARRAY_COPY( target->base.extra_points2, source->base.extra_points2,
389                        num_points );
390       }
391 
392       out->n_points   = (short)num_points;
393       out->n_contours = (short)num_contours;
394 
395       FT_GlyphLoader_Adjust_Points( target );
396     }
397 
398     return error;
399   }
400 
401 
402 /* END */
403