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1 /***************************************************************************/
2 /*                                                                         */
3 /*  ftgloadr.c                                                             */
4 /*                                                                         */
5 /*    The FreeType glyph loader (body).                                    */
6 /*                                                                         */
7 /*  Copyright 2002, 2003, 2004, 2005, 2006, 2010 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_GLYPH_LOADER_H
21 #include FT_INTERNAL_MEMORY_H
22 #include FT_INTERNAL_OBJECTS_H
23 
24 #undef  FT_COMPONENT
25 #define FT_COMPONENT  trace_gloader
26 
27 
28   /*************************************************************************/
29   /*************************************************************************/
30   /*************************************************************************/
31   /*****                                                               *****/
32   /*****                                                               *****/
33   /*****                    G L Y P H   L O A D E R                    *****/
34   /*****                                                               *****/
35   /*****                                                               *****/
36   /*************************************************************************/
37   /*************************************************************************/
38   /*************************************************************************/
39 
40   /*************************************************************************/
41   /*                                                                       */
42   /* The glyph loader is a simple object which is used to load a set of    */
43   /* glyphs easily.  It is critical for the correct loading of composites. */
44   /*                                                                       */
45   /* Ideally, one can see it as a stack of abstract `glyph' objects.       */
46   /*                                                                       */
47   /*   loader.base     Is really the bottom of the stack.  It describes a  */
48   /*                   single glyph image made of the juxtaposition of     */
49   /*                   several glyphs (those `in the stack').              */
50   /*                                                                       */
51   /*   loader.current  Describes the top of the stack, on which a new      */
52   /*                   glyph can be loaded.                                */
53   /*                                                                       */
54   /*   Rewind          Clears the stack.                                   */
55   /*   Prepare         Set up `loader.current' for addition of a new glyph */
56   /*                   image.                                              */
57   /*   Add             Add the `current' glyph image to the `base' one,    */
58   /*                   and prepare for another one.                        */
59   /*                                                                       */
60   /* The glyph loader is now a base object.  Each driver used to           */
61   /* re-implement it in one way or the other, which wasted code and        */
62   /* energy.                                                               */
63   /*                                                                       */
64   /*************************************************************************/
65 
66 
67   /* create a new glyph loader */
68   FT_BASE_DEF( FT_Error )
FT_GlyphLoader_New(FT_Memory memory,FT_GlyphLoader * aloader)69   FT_GlyphLoader_New( FT_Memory        memory,
70                       FT_GlyphLoader  *aloader )
71   {
72     FT_GlyphLoader  loader = NULL;
73     FT_Error        error;
74 
75 
76     if ( !FT_NEW( loader ) )
77     {
78       loader->memory = memory;
79       *aloader       = loader;
80     }
81     return error;
82   }
83 
84 
85   /* rewind the glyph loader - reset counters to 0 */
86   FT_BASE_DEF( void )
FT_GlyphLoader_Rewind(FT_GlyphLoader loader)87   FT_GlyphLoader_Rewind( FT_GlyphLoader  loader )
88   {
89     FT_GlyphLoad  base    = &loader->base;
90     FT_GlyphLoad  current = &loader->current;
91 
92 
93     base->outline.n_points   = 0;
94     base->outline.n_contours = 0;
95     base->num_subglyphs      = 0;
96 
97     *current = *base;
98   }
99 
100 
101   /* reset the glyph loader, frees all allocated tables */
102   /* and starts from zero                               */
103   FT_BASE_DEF( void )
FT_GlyphLoader_Reset(FT_GlyphLoader loader)104   FT_GlyphLoader_Reset( FT_GlyphLoader  loader )
105   {
106     FT_Memory memory = loader->memory;
107 
108 
109     FT_FREE( loader->base.outline.points );
110     FT_FREE( loader->base.outline.tags );
111     FT_FREE( loader->base.outline.contours );
112     FT_FREE( loader->base.extra_points );
113     FT_FREE( loader->base.subglyphs );
114 
115     loader->base.extra_points2 = NULL;
116 
117     loader->max_points    = 0;
118     loader->max_contours  = 0;
119     loader->max_subglyphs = 0;
120 
121     FT_GlyphLoader_Rewind( loader );
122   }
123 
124 
125   /* delete a glyph loader */
126   FT_BASE_DEF( void )
FT_GlyphLoader_Done(FT_GlyphLoader loader)127   FT_GlyphLoader_Done( FT_GlyphLoader  loader )
128   {
129     if ( loader )
130     {
131       FT_Memory memory = loader->memory;
132 
133 
134       FT_GlyphLoader_Reset( loader );
135       FT_FREE( loader );
136     }
137   }
138 
139 
140   /* re-adjust the `current' outline fields */
141   static void
FT_GlyphLoader_Adjust_Points(FT_GlyphLoader loader)142   FT_GlyphLoader_Adjust_Points( FT_GlyphLoader  loader )
143   {
144     FT_Outline*  base    = &loader->base.outline;
145     FT_Outline*  current = &loader->current.outline;
146 
147 
148     current->points   = base->points   + base->n_points;
149     current->tags     = base->tags     + base->n_points;
150     current->contours = base->contours + base->n_contours;
151 
152     /* handle extra points table - if any */
153     if ( loader->use_extra )
154     {
155       loader->current.extra_points  = loader->base.extra_points +
156                                       base->n_points;
157 
158       loader->current.extra_points2 = loader->base.extra_points2 +
159                                       base->n_points;
160     }
161   }
162 
163 
164   FT_BASE_DEF( FT_Error )
FT_GlyphLoader_CreateExtra(FT_GlyphLoader loader)165   FT_GlyphLoader_CreateExtra( FT_GlyphLoader  loader )
166   {
167     FT_Error   error;
168     FT_Memory  memory = loader->memory;
169 
170 
171     if ( !FT_NEW_ARRAY( loader->base.extra_points, 2 * loader->max_points ) )
172     {
173       loader->use_extra          = 1;
174       loader->base.extra_points2 = loader->base.extra_points +
175                                    loader->max_points;
176 
177       FT_GlyphLoader_Adjust_Points( loader );
178     }
179     return error;
180   }
181 
182 
183   /* re-adjust the `current' subglyphs field */
184   static void
FT_GlyphLoader_Adjust_Subglyphs(FT_GlyphLoader loader)185   FT_GlyphLoader_Adjust_Subglyphs( FT_GlyphLoader  loader )
186   {
187     FT_GlyphLoad  base    = &loader->base;
188     FT_GlyphLoad  current = &loader->current;
189 
190 
191     current->subglyphs = base->subglyphs + base->num_subglyphs;
192   }
193 
194 
195   /* Ensure that we can add `n_points' and `n_contours' to our glyph.      */
196   /* This function reallocates its outline tables if necessary.  Note that */
197   /* it DOESN'T change the number of points within the loader!             */
198   /*                                                                       */
199   FT_BASE_DEF( FT_Error )
FT_GlyphLoader_CheckPoints(FT_GlyphLoader loader,FT_UInt n_points,FT_UInt n_contours)200   FT_GlyphLoader_CheckPoints( FT_GlyphLoader  loader,
201                               FT_UInt         n_points,
202                               FT_UInt         n_contours )
203   {
204     FT_Memory    memory  = loader->memory;
205     FT_Error     error   = FT_Err_Ok;
206     FT_Outline*  base    = &loader->base.outline;
207     FT_Outline*  current = &loader->current.outline;
208     FT_Bool      adjust  = 0;
209 
210     FT_UInt      new_max, old_max;
211 
212 
213     /* check points & tags */
214     new_max = base->n_points + current->n_points + n_points;
215     old_max = loader->max_points;
216 
217     if ( new_max > old_max )
218     {
219       new_max = FT_PAD_CEIL( new_max, 8 );
220 
221       if ( new_max > FT_OUTLINE_POINTS_MAX )
222         return FT_Err_Array_Too_Large;
223 
224       if ( FT_RENEW_ARRAY( base->points, old_max, new_max ) ||
225            FT_RENEW_ARRAY( base->tags,   old_max, new_max ) )
226         goto Exit;
227 
228       if ( loader->use_extra )
229       {
230         if ( FT_RENEW_ARRAY( loader->base.extra_points,
231                              old_max * 2, new_max * 2 ) )
232           goto Exit;
233 
234         FT_ARRAY_MOVE( loader->base.extra_points + new_max,
235                        loader->base.extra_points + old_max,
236                        old_max );
237 
238         loader->base.extra_points2 = loader->base.extra_points + new_max;
239       }
240 
241       adjust = 1;
242       loader->max_points = new_max;
243     }
244 
245     /* check contours */
246     old_max = loader->max_contours;
247     new_max = base->n_contours + current->n_contours +
248               n_contours;
249     if ( new_max > old_max )
250     {
251       new_max = FT_PAD_CEIL( new_max, 4 );
252 
253       if ( new_max > FT_OUTLINE_CONTOURS_MAX )
254         return FT_Err_Array_Too_Large;
255 
256       if ( FT_RENEW_ARRAY( base->contours, old_max, new_max ) )
257         goto Exit;
258 
259       adjust = 1;
260       loader->max_contours = new_max;
261     }
262 
263     if ( adjust )
264       FT_GlyphLoader_Adjust_Points( loader );
265 
266   Exit:
267     return error;
268   }
269 
270 
271   /* Ensure that we can add `n_subglyphs' to our glyph. this function */
272   /* reallocates its subglyphs table if necessary.  Note that it DOES */
273   /* NOT change the number of subglyphs within the loader!            */
274   /*                                                                  */
275   FT_BASE_DEF( FT_Error )
FT_GlyphLoader_CheckSubGlyphs(FT_GlyphLoader loader,FT_UInt n_subs)276   FT_GlyphLoader_CheckSubGlyphs( FT_GlyphLoader  loader,
277                                  FT_UInt         n_subs )
278   {
279     FT_Memory     memory = loader->memory;
280     FT_Error      error  = FT_Err_Ok;
281     FT_UInt       new_max, old_max;
282 
283     FT_GlyphLoad  base    = &loader->base;
284     FT_GlyphLoad  current = &loader->current;
285 
286 
287     new_max = base->num_subglyphs + current->num_subglyphs + n_subs;
288     old_max = loader->max_subglyphs;
289     if ( new_max > old_max )
290     {
291       new_max = FT_PAD_CEIL( new_max, 2 );
292       if ( FT_RENEW_ARRAY( base->subglyphs, old_max, new_max ) )
293         goto Exit;
294 
295       loader->max_subglyphs = new_max;
296 
297       FT_GlyphLoader_Adjust_Subglyphs( loader );
298     }
299 
300   Exit:
301     return error;
302   }
303 
304 
305   /* prepare loader for the addition of a new glyph on top of the base one */
306   FT_BASE_DEF( void )
FT_GlyphLoader_Prepare(FT_GlyphLoader loader)307   FT_GlyphLoader_Prepare( FT_GlyphLoader  loader )
308   {
309     FT_GlyphLoad  current = &loader->current;
310 
311 
312     current->outline.n_points   = 0;
313     current->outline.n_contours = 0;
314     current->num_subglyphs      = 0;
315 
316     FT_GlyphLoader_Adjust_Points   ( loader );
317     FT_GlyphLoader_Adjust_Subglyphs( loader );
318   }
319 
320 
321   /* add current glyph to the base image - and prepare for another */
322   FT_BASE_DEF( void )
FT_GlyphLoader_Add(FT_GlyphLoader loader)323   FT_GlyphLoader_Add( FT_GlyphLoader  loader )
324   {
325     FT_GlyphLoad  base;
326     FT_GlyphLoad  current;
327 
328     FT_UInt       n_curr_contours;
329     FT_UInt       n_base_points;
330     FT_UInt       n;
331 
332 
333     if ( !loader )
334       return;
335 
336     base    = &loader->base;
337     current = &loader->current;
338 
339     n_curr_contours = current->outline.n_contours;
340     n_base_points   = base->outline.n_points;
341 
342     base->outline.n_points =
343       (short)( base->outline.n_points + current->outline.n_points );
344     base->outline.n_contours =
345       (short)( base->outline.n_contours + current->outline.n_contours );
346 
347     base->num_subglyphs += current->num_subglyphs;
348 
349     /* adjust contours count in newest outline */
350     for ( n = 0; n < n_curr_contours; n++ )
351       current->outline.contours[n] =
352         (short)( current->outline.contours[n] + n_base_points );
353 
354     /* prepare for another new glyph image */
355     FT_GlyphLoader_Prepare( loader );
356   }
357 
358 
359   FT_BASE_DEF( FT_Error )
FT_GlyphLoader_CopyPoints(FT_GlyphLoader target,FT_GlyphLoader source)360   FT_GlyphLoader_CopyPoints( FT_GlyphLoader  target,
361                              FT_GlyphLoader  source )
362   {
363     FT_Error  error;
364     FT_UInt   num_points   = source->base.outline.n_points;
365     FT_UInt   num_contours = source->base.outline.n_contours;
366 
367 
368     error = FT_GlyphLoader_CheckPoints( target, num_points, num_contours );
369     if ( !error )
370     {
371       FT_Outline*  out = &target->base.outline;
372       FT_Outline*  in  = &source->base.outline;
373 
374 
375       FT_ARRAY_COPY( out->points, in->points,
376                      num_points );
377       FT_ARRAY_COPY( out->tags, in->tags,
378                      num_points );
379       FT_ARRAY_COPY( out->contours, in->contours,
380                      num_contours );
381 
382       /* do we need to copy the extra points? */
383       if ( target->use_extra && source->use_extra )
384       {
385         FT_ARRAY_COPY( target->base.extra_points, source->base.extra_points,
386                        num_points );
387         FT_ARRAY_COPY( target->base.extra_points2, source->base.extra_points2,
388                        num_points );
389       }
390 
391       out->n_points   = (short)num_points;
392       out->n_contours = (short)num_contours;
393 
394       FT_GlyphLoader_Adjust_Points( target );
395     }
396 
397     return error;
398   }
399 
400 
401 /* END */
402