hb-font.cc revision abcfe9b59b4475eb02dd679aac4bc59616713b28 
1/*
2 * Copyright © 2009  Red Hat, Inc.
3 *
4 *  This is part of HarfBuzz, a text shaping library.
5 *
6 * Permission is hereby granted, without written agreement and without
7 * license or royalty fees, to use, copy, modify, and distribute this
8 * software and its documentation for any purpose, provided that the
9 * above copyright notice and the following two paragraphs appear in
10 * all copies of this software.
11 *
12 * IN NO EVENT SHALL THE COPYRIGHT HOLDER BE LIABLE TO ANY PARTY FOR
13 * DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES
14 * ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN
15 * IF THE COPYRIGHT HOLDER HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH
16 * DAMAGE.
17 *
18 * THE COPYRIGHT HOLDER SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING,
19 * BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
20 * FITNESS FOR A PARTICULAR PURPOSE.  THE SOFTWARE PROVIDED HEREUNDER IS
21 * ON AN "AS IS" BASIS, AND THE COPYRIGHT HOLDER HAS NO OBLIGATION TO
22 * PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.
23 *
24 * Red Hat Author(s): Behdad Esfahbod
25 */
26
27#include "hb-private.hh"
28
29#include "hb-ot-layout-private.hh"
30
31#include "hb-font-private.hh"
32#include "hb-blob.h"
33#include "hb-open-file-private.hh"
34
35#include <string.h>
36
37HB_BEGIN_DECLS
38
39
40/*
41 * hb_font_funcs_t
42 */
43
44static hb_bool_t
45hb_font_get_contour_point_nil (hb_font_t *font HB_UNUSED,
46			       const void *font_data HB_UNUSED,
47			       unsigned int point_index HB_UNUSED,
48			       hb_codepoint_t glyph HB_UNUSED,
49			       hb_position_t *x HB_UNUSED,
50			       hb_position_t *y HB_UNUSED,
51			       const void *user_data HB_UNUSED)
52{
53  if (font->parent)
54    return hb_font_get_contour_point (font->parent,
55				      point_index, glyph,
56				      x, y);
57
58  *x = *y = 0;
59
60  return false;
61}
62
63static void
64hb_font_get_glyph_advance_nil (hb_font_t *font HB_UNUSED,
65			       const void *font_data HB_UNUSED,
66			       hb_codepoint_t glyph HB_UNUSED,
67			       hb_position_t *x_advance HB_UNUSED,
68			       hb_position_t *y_advance HB_UNUSED,
69			       const void *user_data HB_UNUSED)
70{
71  if (font->parent) {
72    hb_font_get_glyph_advance (font->parent, glyph, x_advance, y_advance);
73    return;
74  }
75
76  *x_advance = *y_advance = 0;
77}
78
79static void
80hb_font_get_glyph_extents_nil (hb_font_t *font HB_UNUSED,
81			       const void *font_data HB_UNUSED,
82			       hb_codepoint_t glyph HB_UNUSED,
83			       hb_glyph_extents_t *extents HB_UNUSED,
84			       const void *user_data HB_UNUSED)
85{
86  if (font->parent) {
87    hb_font_get_glyph_extents (font->parent, glyph, extents);
88    return;
89  }
90
91  extents->x_bearing = extents->y_bearing = 0;
92  extents->width = extents->height = 0;
93}
94
95static hb_codepoint_t
96hb_font_get_glyph_nil (hb_font_t *font HB_UNUSED,
97		       const void *font_data HB_UNUSED,
98		       hb_codepoint_t unicode HB_UNUSED,
99		       hb_codepoint_t variation_selector HB_UNUSED,
100		       const void *user_data HB_UNUSED)
101{
102  if (font->parent)
103    return hb_font_get_glyph (font->parent, unicode, variation_selector);
104
105  return 0;
106}
107
108static hb_position_t
109hb_font_get_kerning_nil (hb_font_t *font HB_UNUSED,
110			 const void *font_data HB_UNUSED,
111			 hb_codepoint_t first_glyph HB_UNUSED,
112			 hb_codepoint_t second_glyph HB_UNUSED,
113			 const void *user_data HB_UNUSED)
114{
115  if (font->parent)
116    return hb_font_get_kerning (font->parent, first_glyph, second_glyph);
117
118  return 0;
119}
120
121
122static hb_font_funcs_t _hb_font_funcs_nil = {
123  HB_OBJECT_HEADER_STATIC,
124
125  TRUE, /* immutable */
126
127  {
128    hb_font_get_contour_point_nil,
129    hb_font_get_glyph_advance_nil,
130    hb_font_get_glyph_extents_nil,
131    hb_font_get_glyph_nil,
132    hb_font_get_kerning_nil
133  }
134};
135
136
137hb_font_funcs_t *
138hb_font_funcs_create (void)
139{
140  hb_font_funcs_t *ffuncs;
141
142  if (!(ffuncs = hb_object_create<hb_font_funcs_t> ()))
143    return &_hb_font_funcs_nil;
144
145  ffuncs->get = _hb_font_funcs_nil.get;
146
147  return ffuncs;
148}
149
150hb_font_funcs_t *
151hb_font_funcs_reference (hb_font_funcs_t *ffuncs)
152{
153  return hb_object_reference (ffuncs);
154}
155
156void
157hb_font_funcs_destroy (hb_font_funcs_t *ffuncs)
158{
159  if (!hb_object_destroy (ffuncs)) return;
160
161#define DESTROY(name) if (ffuncs->destroy.name) ffuncs->destroy.name (ffuncs->user_data.name)
162  DESTROY (contour_point);
163  DESTROY (glyph_advance);
164  DESTROY (glyph_extents);
165  DESTROY (glyph);
166  DESTROY (kerning);
167#undef DESTROY
168
169  free (ffuncs);
170}
171
172hb_bool_t
173hb_font_funcs_set_user_data (hb_font_funcs_t    *ffuncs,
174			     hb_user_data_key_t *key,
175			     void *              data,
176			     hb_destroy_func_t   destroy)
177{
178  return hb_object_set_user_data (ffuncs, key, data, destroy);
179}
180
181void *
182hb_font_funcs_get_user_data (hb_font_funcs_t    *ffuncs,
183			     hb_user_data_key_t *key)
184{
185  return hb_object_get_user_data (ffuncs, key);
186}
187
188
189void
190hb_font_funcs_make_immutable (hb_font_funcs_t *ffuncs)
191{
192  if (hb_object_is_inert (ffuncs))
193    return;
194
195  ffuncs->immutable = TRUE;
196}
197
198hb_bool_t
199hb_font_funcs_is_immutable (hb_font_funcs_t *ffuncs)
200{
201  return ffuncs->immutable;
202}
203
204
205#define IMPLEMENT(name)                                                  \
206                                                                         \
207void                                                                     \
208hb_font_funcs_set_##name##_func (hb_font_funcs_t             *ffuncs,    \
209                                 hb_font_get_##name##_func_t  func,      \
210                                 void                        *user_data, \
211                                 hb_destroy_func_t            destroy)   \
212{                                                                        \
213  if (ffuncs->immutable)                                                 \
214    return;                                                              \
215                                                                         \
216  if (ffuncs->destroy.name)                                              \
217    ffuncs->destroy.name (ffuncs->user_data.name);                       \
218                                                                         \
219  if (func) {                                                            \
220    ffuncs->get.name = func;                                             \
221    ffuncs->user_data.name = user_data;                                  \
222    ffuncs->destroy.name = destroy;                                      \
223  } else {                                                               \
224    ffuncs->get.name = hb_font_get_##name##_nil;                         \
225    ffuncs->user_data.name = NULL;                                       \
226    ffuncs->destroy.name = NULL;                                         \
227  }                                                                      \
228}
229
230IMPLEMENT (contour_point);
231IMPLEMENT (glyph_advance);
232IMPLEMENT (glyph_extents);
233IMPLEMENT (glyph);
234IMPLEMENT (kerning);
235
236#undef IMPLEMENT
237
238
239hb_bool_t
240hb_font_get_contour_point (hb_font_t *font,
241			   unsigned int point_index,
242			   hb_codepoint_t glyph, hb_position_t *x, hb_position_t *y)
243{
244  *x = 0; *y = 0;
245  return font->klass->get.contour_point (font, font->user_data,
246					 point_index,
247					 glyph, x, y,
248					 font->klass->user_data.contour_point);
249}
250
251void
252hb_font_get_glyph_advance (hb_font_t *font,
253			   hb_codepoint_t glyph,
254			   hb_position_t *x_advance, hb_position_t *y_advance)
255{
256  *x_advance = *y_advance = 0;
257  return font->klass->get.glyph_advance (font, font->user_data,
258					 glyph, x_advance, y_advance,
259					 font->klass->user_data.glyph_advance);
260}
261
262void
263hb_font_get_glyph_extents (hb_font_t *font,
264			   hb_codepoint_t glyph, hb_glyph_extents_t *extents)
265{
266  memset (extents, 0, sizeof (*extents));
267  return font->klass->get.glyph_extents (font, font->user_data,
268					 glyph, extents,
269					 font->klass->user_data.glyph_extents);
270}
271
272hb_codepoint_t
273hb_font_get_glyph (hb_font_t *font,
274		   hb_codepoint_t unicode, hb_codepoint_t variation_selector)
275{
276  return font->klass->get.glyph (font, font->user_data,
277				 unicode, variation_selector,
278				 font->klass->user_data.glyph);
279}
280
281hb_position_t
282hb_font_get_kerning (hb_font_t *font,
283		     hb_codepoint_t first_glyph, hb_codepoint_t second_glyph)
284{
285  return font->klass->get.kerning (font, font->user_data,
286				   first_glyph, second_glyph,
287				   font->klass->user_data.kerning);
288}
289
290
291/*
292 * hb_face_t
293 */
294
295static hb_face_t _hb_face_nil = {
296  HB_OBJECT_HEADER_STATIC,
297
298  NULL, /* get_table */
299  NULL, /* user_data */
300  NULL, /* destroy */
301
302  NULL, /* ot_layout */
303
304  1000
305};
306
307
308hb_face_t *
309hb_face_create_for_tables (hb_get_table_func_t  get_table,
310			   void                *user_data,
311			   hb_destroy_func_t    destroy)
312{
313  hb_face_t *face;
314
315  if (!get_table || !(face = hb_object_create<hb_face_t> ())) {
316    if (destroy)
317      destroy (user_data);
318    return &_hb_face_nil;
319  }
320
321  face->get_table = get_table;
322  face->user_data = user_data;
323  face->destroy = destroy;
324
325  face->ot_layout = _hb_ot_layout_create (face);
326
327  face->upem = _hb_ot_layout_get_upem (face);
328
329  return face;
330}
331
332
333typedef struct _hb_face_for_data_closure_t {
334  hb_blob_t *blob;
335  unsigned int  index;
336} hb_face_for_data_closure_t;
337
338static hb_face_for_data_closure_t *
339_hb_face_for_data_closure_create (hb_blob_t *blob, unsigned int index)
340{
341  hb_face_for_data_closure_t *closure;
342
343  closure = (hb_face_for_data_closure_t *) malloc (sizeof (hb_face_for_data_closure_t));
344  if (unlikely (!closure))
345    return NULL;
346
347  closure->blob = blob;
348  closure->index = index;
349
350  return closure;
351}
352
353static void
354_hb_face_for_data_closure_destroy (hb_face_for_data_closure_t *closure)
355{
356  hb_blob_destroy (closure->blob);
357  free (closure);
358}
359
360static hb_blob_t *
361_hb_face_for_data_get_table (hb_tag_t tag, void *user_data)
362{
363  hb_face_for_data_closure_t *data = (hb_face_for_data_closure_t *) user_data;
364
365  const OpenTypeFontFile &ot_file = *Sanitizer<OpenTypeFontFile>::lock_instance (data->blob);
366  const OpenTypeFontFace &ot_face = ot_file.get_face (data->index);
367
368  const OpenTypeTable &table = ot_face.get_table_by_tag (tag);
369
370  hb_blob_t *blob = hb_blob_create_sub_blob (data->blob, table.offset, table.length);
371
372  return blob;
373}
374
375hb_face_t *
376hb_face_create_for_data (hb_blob_t    *blob,
377			 unsigned int  index)
378{
379  if (unlikely (!blob || !hb_blob_get_length (blob)))
380    return &_hb_face_nil;
381
382  hb_face_for_data_closure_t *closure = _hb_face_for_data_closure_create (Sanitizer<OpenTypeFontFile>::sanitize (hb_blob_reference (blob)), index);
383
384  if (unlikely (!closure))
385    return &_hb_face_nil;
386
387  return hb_face_create_for_tables (_hb_face_for_data_get_table,
388				    closure,
389				    (hb_destroy_func_t) _hb_face_for_data_closure_destroy);
390}
391
392
393hb_face_t *
394hb_face_reference (hb_face_t *face)
395{
396  return hb_object_reference (face);
397}
398
399void
400hb_face_destroy (hb_face_t *face)
401{
402  if (!hb_object_destroy (face)) return;
403
404  _hb_ot_layout_destroy (face->ot_layout);
405
406  if (face->destroy)
407    face->destroy (face->user_data);
408
409  free (face);
410}
411
412hb_bool_t
413hb_face_set_user_data (hb_face_t          *face,
414		       hb_user_data_key_t *key,
415		       void *              data,
416		       hb_destroy_func_t   destroy)
417{
418  return hb_object_set_user_data (face, key, data, destroy);
419}
420
421void *
422hb_face_get_user_data (hb_face_t          *face,
423		       hb_user_data_key_t *key)
424{
425  return hb_object_get_user_data (face, key);
426}
427
428
429hb_blob_t *
430hb_face_reference_table (hb_face_t *face,
431			 hb_tag_t   tag)
432{
433  hb_blob_t *blob;
434
435  if (unlikely (!face || !face->get_table))
436    return hb_blob_get_empty ();
437
438  blob = face->get_table (tag, face->user_data);
439  if (unlikely (!blob))
440    return hb_blob_get_empty ();
441
442  return blob;
443}
444
445unsigned int
446hb_face_get_upem (hb_face_t *face)
447{
448  return _hb_ot_layout_get_upem (face);
449}
450
451
452/*
453 * hb_font_t
454 */
455
456static hb_font_t _hb_font_nil = {
457  HB_OBJECT_HEADER_STATIC,
458
459  TRUE, /* immutable */
460
461  NULL, /* parent */
462  &_hb_face_nil,
463
464  0, /* x_scale */
465  0, /* y_scale */
466
467  0, /* x_ppem */
468  0, /* y_ppem */
469
470  &_hb_font_funcs_nil, /* klass */
471  NULL, /* user_data */
472  NULL  /* destroy */
473};
474
475hb_font_t *
476hb_font_create (hb_face_t *face)
477{
478  hb_font_t *font;
479
480  if (unlikely (!face))
481    face = &_hb_face_nil;
482  if (unlikely (hb_object_is_inert (face)))
483    return &_hb_font_nil;
484  if (!(font = hb_object_create<hb_font_t> ()))
485    return &_hb_font_nil;
486
487  font->face = hb_face_reference (face);
488  font->klass = &_hb_font_funcs_nil;
489
490  return font;
491}
492
493hb_font_t *
494hb_font_create_sub_font (hb_font_t *parent)
495{
496  if (unlikely (!parent))
497    return &_hb_font_nil;
498
499  hb_font_t *font = hb_font_create (parent->face);
500
501  if (unlikely (hb_object_is_inert (font)))
502    return font;
503
504  hb_font_make_immutable (parent);
505  font->parent = hb_font_reference (parent);
506
507  font->x_scale = parent->x_scale;
508  font->y_scale = parent->y_scale;
509  font->x_ppem = parent->x_ppem;
510  font->y_ppem = parent->y_ppem;
511
512  /* We can safely copy user_data from parent since we hold a reference
513   * onto it and it's immutable.  We should not copy the destroy notifiers
514   * though. */
515  font->klass = hb_font_funcs_reference (parent->klass);
516  font->user_data = parent->user_data;
517
518  return font;
519}
520
521hb_font_t *
522hb_font_reference (hb_font_t *font)
523{
524  return hb_object_reference (font);
525}
526
527void
528hb_font_destroy (hb_font_t *font)
529{
530  if (!hb_object_destroy (font)) return;
531
532  hb_font_destroy (font->parent);
533  hb_face_destroy (font->face);
534  hb_font_funcs_destroy (font->klass);
535  if (font->destroy)
536    font->destroy (font->user_data);
537
538  free (font);
539}
540
541hb_bool_t
542hb_font_set_user_data (hb_font_t          *font,
543		       hb_user_data_key_t *key,
544		       void *              data,
545		       hb_destroy_func_t   destroy)
546{
547  return hb_object_set_user_data (font, key, data, destroy);
548}
549
550void *
551hb_font_get_user_data (hb_font_t          *font,
552		       hb_user_data_key_t *key)
553{
554  return hb_object_get_user_data (font, key);
555}
556
557void
558hb_font_make_immutable (hb_font_t *font)
559{
560  if (hb_object_is_inert (font))
561    return;
562
563  font->immutable = true;
564}
565
566hb_bool_t
567hb_font_is_immutable (hb_font_t *font)
568{
569  return font->immutable;
570}
571
572hb_font_t *
573hb_font_get_parent (hb_font_t *font)
574{
575  return font->parent;
576}
577
578hb_face_t *
579hb_font_get_face (hb_font_t *font)
580{
581  return font->face;
582}
583
584
585void
586hb_font_set_funcs (hb_font_t         *font,
587		   hb_font_funcs_t   *klass,
588		   void              *user_data,
589		   hb_destroy_func_t  destroy)
590{
591  if (font->immutable)
592    return;
593
594  if (font->destroy)
595    font->destroy (font->user_data);
596
597  if (!klass)
598    klass = &_hb_font_funcs_nil;
599
600  hb_font_funcs_reference (klass);
601  hb_font_funcs_destroy (font->klass);
602  font->klass = klass;
603  font->user_data = user_data;
604  font->destroy = destroy;
605}
606
607
608void
609hb_font_set_scale (hb_font_t *font,
610		   int x_scale,
611		   int y_scale)
612{
613  if (font->immutable)
614    return;
615
616  font->x_scale = x_scale;
617  font->y_scale = y_scale;
618}
619
620void
621hb_font_get_scale (hb_font_t *font,
622		   int *x_scale,
623		   int *y_scale)
624{
625  if (x_scale) *x_scale = font->x_scale;
626  if (y_scale) *y_scale = font->y_scale;
627}
628
629void
630hb_font_set_ppem (hb_font_t *font,
631		  unsigned int x_ppem,
632		  unsigned int y_ppem)
633{
634  if (font->immutable)
635    return;
636
637  font->x_ppem = x_ppem;
638  font->y_ppem = y_ppem;
639}
640
641void
642hb_font_get_ppem (hb_font_t *font,
643		  unsigned int *x_ppem,
644		  unsigned int *y_ppem)
645{
646  if (x_ppem) *x_ppem = font->x_ppem;
647  if (y_ppem) *y_ppem = font->y_ppem;
648}
649
650
651HB_END_DECLS
652