hb-shape-plan.cc revision dc9aba6fc53898acd7281b118cec0355d61b1df2 
1/*
2 * Copyright © 2012  Google, 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 * Google Author(s): Behdad Esfahbod
25 */
26
27#include "hb-shape-plan-private.hh"
28#include "hb-shaper-private.hh"
29#include "hb-font-private.hh"
30#include "hb-buffer-private.hh"
31
32
33#ifndef HB_DEBUG_SHAPE_PLAN
34#define HB_DEBUG_SHAPE_PLAN (HB_DEBUG+0)
35#endif
36
37
38#define HB_SHAPER_IMPLEMENT(shaper) \
39	HB_SHAPER_DATA_ENSURE_DECLARE(shaper, face) \
40	HB_SHAPER_DATA_ENSURE_DECLARE(shaper, font)
41#include "hb-shaper-list.hh"
42#undef HB_SHAPER_IMPLEMENT
43
44
45static void
46hb_shape_plan_plan (hb_shape_plan_t    *shape_plan,
47		    const hb_feature_t *user_features,
48		    unsigned int        num_user_features,
49		    const char * const *shaper_list)
50{
51  DEBUG_MSG_FUNC (SHAPE_PLAN, shape_plan,
52		  "num_features=%d shaper_list=%p",
53		  num_user_features,
54		  shaper_list);
55
56  const hb_shaper_pair_t *shapers = _hb_shapers_get ();
57
58#define HB_SHAPER_PLAN(shaper) \
59	HB_STMT_START { \
60	  if (hb_##shaper##_shaper_face_data_ensure (shape_plan->face_unsafe)) { \
61	    HB_SHAPER_DATA (shaper, shape_plan) = \
62	      HB_SHAPER_DATA_CREATE_FUNC (shaper, shape_plan) (shape_plan, user_features, num_user_features); \
63	    shape_plan->shaper_func = _hb_##shaper##_shape; \
64	    shape_plan->shaper_name = #shaper; \
65	    return; \
66	  } \
67	} HB_STMT_END
68
69  if (likely (!shaper_list)) {
70    for (unsigned int i = 0; i < HB_SHAPERS_COUNT; i++)
71      if (0)
72	;
73#define HB_SHAPER_IMPLEMENT(shaper) \
74      else if (shapers[i].func == _hb_##shaper##_shape) \
75	HB_SHAPER_PLAN (shaper);
76#include "hb-shaper-list.hh"
77#undef HB_SHAPER_IMPLEMENT
78  } else {
79    for (; *shaper_list; shaper_list++)
80      if (0)
81	;
82#define HB_SHAPER_IMPLEMENT(shaper) \
83      else if (0 == strcmp (*shaper_list, #shaper)) \
84	HB_SHAPER_PLAN (shaper);
85#include "hb-shaper-list.hh"
86#undef HB_SHAPER_IMPLEMENT
87  }
88
89#undef HB_SHAPER_PLAN
90}
91
92
93/*
94 * hb_shape_plan_t
95 */
96
97/**
98 * hb_shape_plan_create: (Xconstructor)
99 * @face:
100 * @props:
101 * @user_features: (array length=num_user_features):
102 * @num_user_features:
103 * @shaper_list: (array zero-terminated=1):
104 *
105 *
106 *
107 * Return value: (transfer full):
108 *
109 * Since: 1.0
110 **/
111hb_shape_plan_t *
112hb_shape_plan_create (hb_face_t                     *face,
113		      const hb_segment_properties_t *props,
114		      const hb_feature_t            *user_features,
115		      unsigned int                   num_user_features,
116		      const char * const            *shaper_list)
117{
118  DEBUG_MSG_FUNC (SHAPE_PLAN, NULL,
119		  "face=%p num_features=%d shaper_list=%p",
120		  face,
121		  num_user_features,
122		  shaper_list);
123
124  hb_shape_plan_t *shape_plan;
125  hb_feature_t *features = NULL;
126
127  if (unlikely (!face))
128    face = hb_face_get_empty ();
129  if (unlikely (!props || hb_object_is_inert (face)))
130    return hb_shape_plan_get_empty ();
131  if (num_user_features && !(features = (hb_feature_t *) malloc (num_user_features * sizeof (hb_feature_t))))
132    return hb_shape_plan_get_empty ();
133  if (!(shape_plan = hb_object_create<hb_shape_plan_t> ())) {
134    free (features);
135    return hb_shape_plan_get_empty ();
136  }
137
138  assert (props->direction != HB_DIRECTION_INVALID);
139
140  hb_face_make_immutable (face);
141  shape_plan->default_shaper_list = shaper_list == NULL;
142  shape_plan->face_unsafe = face;
143  shape_plan->props = *props;
144  shape_plan->num_user_features = num_user_features;
145  shape_plan->user_features = features;
146  if (num_user_features)
147    memcpy (features, user_features, num_user_features * sizeof (hb_feature_t));
148
149  hb_shape_plan_plan (shape_plan, user_features, num_user_features, shaper_list);
150
151  return shape_plan;
152}
153
154/**
155 * hb_shape_plan_get_empty:
156 *
157 *
158 *
159 * Return value: (transfer full):
160 *
161 * Since: 1.0
162 **/
163hb_shape_plan_t *
164hb_shape_plan_get_empty (void)
165{
166  static const hb_shape_plan_t _hb_shape_plan_nil = {
167    HB_OBJECT_HEADER_STATIC,
168
169    true, /* default_shaper_list */
170    NULL, /* face */
171    HB_SEGMENT_PROPERTIES_DEFAULT, /* props */
172
173    NULL, /* shaper_func */
174    NULL, /* shaper_name */
175
176    NULL, /* user_features */
177    0,    /* num_user_featurs */
178
179    {
180#define HB_SHAPER_IMPLEMENT(shaper) HB_SHAPER_DATA_INVALID,
181#include "hb-shaper-list.hh"
182#undef HB_SHAPER_IMPLEMENT
183    }
184  };
185
186  return const_cast<hb_shape_plan_t *> (&_hb_shape_plan_nil);
187}
188
189/**
190 * hb_shape_plan_reference: (skip)
191 * @shape_plan: a shape plan.
192 *
193 *
194 *
195 * Return value: (transfer full):
196 *
197 * Since: 1.0
198 **/
199hb_shape_plan_t *
200hb_shape_plan_reference (hb_shape_plan_t *shape_plan)
201{
202  return hb_object_reference (shape_plan);
203}
204
205/**
206 * hb_shape_plan_destroy: (skip)
207 * @shape_plan: a shape plan.
208 *
209 *
210 *
211 * Since: 1.0
212 **/
213void
214hb_shape_plan_destroy (hb_shape_plan_t *shape_plan)
215{
216  if (!hb_object_destroy (shape_plan)) return;
217
218#define HB_SHAPER_IMPLEMENT(shaper) HB_SHAPER_DATA_DESTROY(shaper, shape_plan);
219#include "hb-shaper-list.hh"
220#undef HB_SHAPER_IMPLEMENT
221
222  free (shape_plan->user_features);
223
224  free (shape_plan);
225}
226
227/**
228 * hb_shape_plan_set_user_data: (skip)
229 * @shape_plan: a shape plan.
230 * @key:
231 * @data:
232 * @destroy:
233 * @replace:
234 *
235 *
236 *
237 * Return value:
238 *
239 * Since: 1.0
240 **/
241hb_bool_t
242hb_shape_plan_set_user_data (hb_shape_plan_t    *shape_plan,
243			     hb_user_data_key_t *key,
244			     void *              data,
245			     hb_destroy_func_t   destroy,
246			     hb_bool_t           replace)
247{
248  return hb_object_set_user_data (shape_plan, key, data, destroy, replace);
249}
250
251/**
252 * hb_shape_plan_get_user_data: (skip)
253 * @shape_plan: a shape plan.
254 * @key:
255 *
256 *
257 *
258 * Return value: (transfer none):
259 *
260 * Since: 1.0
261 **/
262void *
263hb_shape_plan_get_user_data (hb_shape_plan_t    *shape_plan,
264			     hb_user_data_key_t *key)
265{
266  return hb_object_get_user_data (shape_plan, key);
267}
268
269
270/**
271 * hb_shape_plan_execute:
272 * @shape_plan: a shape plan.
273 * @font: a font.
274 * @buffer: a buffer.
275 * @features: (array length=num_features):
276 * @num_features:
277 *
278 *
279 *
280 * Return value:
281 *
282 * Since: 1.0
283 **/
284hb_bool_t
285hb_shape_plan_execute (hb_shape_plan_t    *shape_plan,
286		       hb_font_t          *font,
287		       hb_buffer_t        *buffer,
288		       const hb_feature_t *features,
289		       unsigned int        num_features)
290{
291  DEBUG_MSG_FUNC (SHAPE_PLAN, shape_plan,
292		  "num_features=%d shaper_func=%p",
293		  num_features,
294		  shape_plan->shaper_func);
295
296  if (unlikely (hb_object_is_inert (shape_plan) ||
297		hb_object_is_inert (font) ||
298		hb_object_is_inert (buffer)))
299    return false;
300
301  assert (shape_plan->face_unsafe == font->face);
302  assert (hb_segment_properties_equal (&shape_plan->props, &buffer->props));
303
304#define HB_SHAPER_EXECUTE(shaper) \
305	HB_STMT_START { \
306	  return HB_SHAPER_DATA (shaper, shape_plan) && \
307		 hb_##shaper##_shaper_font_data_ensure (font) && \
308		 _hb_##shaper##_shape (shape_plan, font, buffer, features, num_features); \
309	} HB_STMT_END
310
311  if (0)
312    ;
313#define HB_SHAPER_IMPLEMENT(shaper) \
314  else if (shape_plan->shaper_func == _hb_##shaper##_shape) \
315    HB_SHAPER_EXECUTE (shaper);
316#include "hb-shaper-list.hh"
317#undef HB_SHAPER_IMPLEMENT
318
319#undef HB_SHAPER_EXECUTE
320
321  return false;
322}
323
324
325/*
326 * caching
327 */
328
329#if 0
330static unsigned int
331hb_shape_plan_hash (const hb_shape_plan_t *shape_plan)
332{
333  return hb_segment_properties_hash (&shape_plan->props) +
334	 shape_plan->default_shaper_list ? 0 : (intptr_t) shape_plan->shaper_func;
335}
336#endif
337
338/* User-feature caching is currently somewhat dumb:
339 * it only finds matches where the feature array is identical,
340 * not cases where the feature lists would be compatible for plan purposes
341 * but have different ranges, for example.
342 */
343struct hb_shape_plan_proposal_t
344{
345  const hb_segment_properties_t  props;
346  const char * const            *shaper_list;
347  const hb_feature_t            *user_features;
348  unsigned int                   num_user_features;
349  hb_shape_func_t               *shaper_func;
350};
351
352static inline hb_bool_t
353hb_shape_plan_user_features_match (const hb_shape_plan_t          *shape_plan,
354				   const hb_shape_plan_proposal_t *proposal)
355{
356  if (proposal->num_user_features != shape_plan->num_user_features) return false;
357  for (unsigned int i = 0, n = proposal->num_user_features; i < n; i++)
358    if (proposal->user_features[i].tag   != shape_plan->user_features[i].tag   ||
359        proposal->user_features[i].value != shape_plan->user_features[i].value ||
360        proposal->user_features[i].start != shape_plan->user_features[i].start ||
361        proposal->user_features[i].end   != shape_plan->user_features[i].end) return false;
362  return true;
363}
364
365static hb_bool_t
366hb_shape_plan_matches (const hb_shape_plan_t          *shape_plan,
367		       const hb_shape_plan_proposal_t *proposal)
368{
369  return hb_segment_properties_equal (&shape_plan->props, &proposal->props) &&
370	 hb_shape_plan_user_features_match (shape_plan, proposal) &&
371	 ((shape_plan->default_shaper_list && proposal->shaper_list == NULL) ||
372	  (shape_plan->shaper_func == proposal->shaper_func));
373}
374
375static inline hb_bool_t
376hb_non_global_user_features_present (const hb_feature_t *user_features,
377				     unsigned int        num_user_features)
378{
379  while (num_user_features)
380    if (user_features->start != 0 || user_features->end != (unsigned int) -1)
381      return true;
382    else
383      num_user_features--, user_features++;
384  return false;
385}
386
387/**
388 * hb_shape_plan_create_cached:
389 * @face:
390 * @props:
391 * @user_features: (array length=num_user_features):
392 * @num_user_features:
393 * @shaper_list: (array zero-terminated=1):
394 *
395 *
396 *
397 * Return value: (transfer full):
398 *
399 * Since: 1.0
400 **/
401hb_shape_plan_t *
402hb_shape_plan_create_cached (hb_face_t                     *face,
403			     const hb_segment_properties_t *props,
404			     const hb_feature_t            *user_features,
405			     unsigned int                   num_user_features,
406			     const char * const            *shaper_list)
407{
408  DEBUG_MSG_FUNC (SHAPE_PLAN, NULL,
409		  "face=%p num_features=%d shaper_list=%p",
410		  face,
411		  num_user_features,
412		  shaper_list);
413
414  hb_shape_plan_proposal_t proposal = {
415    *props,
416    shaper_list,
417    user_features,
418    num_user_features,
419    NULL
420  };
421
422  if (shaper_list) {
423    /* Choose shaper.  Adapted from hb_shape_plan_plan().
424     * Must choose shaper exactly the same way as that function. */
425    for (const char * const *shaper_item = shaper_list; *shaper_item; shaper_item++)
426      if (0)
427	;
428#define HB_SHAPER_IMPLEMENT(shaper) \
429      else if (0 == strcmp (*shaper_item, #shaper) && \
430	       hb_##shaper##_shaper_face_data_ensure (face)) \
431      { \
432	proposal.shaper_func = _hb_##shaper##_shape; \
433	break; \
434      }
435#include "hb-shaper-list.hh"
436#undef HB_SHAPER_IMPLEMENT
437
438    if (unlikely (!proposal.shaper_list))
439      return hb_shape_plan_get_empty ();
440  }
441
442
443retry:
444  hb_face_t::plan_node_t *cached_plan_nodes = (hb_face_t::plan_node_t *) hb_atomic_ptr_get (&face->shape_plans);
445  for (hb_face_t::plan_node_t *node = cached_plan_nodes; node; node = node->next)
446    if (hb_shape_plan_matches (node->shape_plan, &proposal))
447    {
448      DEBUG_MSG_FUNC (SHAPE_PLAN, node->shape_plan, "fulfilled from cache");
449      return hb_shape_plan_reference (node->shape_plan);
450    }
451
452  /* Not found. */
453
454  hb_shape_plan_t *shape_plan = hb_shape_plan_create (face, props, user_features, num_user_features, shaper_list);
455
456  /* Don't add the plan to the cache if there were user features with non-global ranges */
457
458  if (hb_non_global_user_features_present (user_features, num_user_features))
459    return shape_plan;
460
461  hb_face_t::plan_node_t *node = (hb_face_t::plan_node_t *) calloc (1, sizeof (hb_face_t::plan_node_t));
462  if (unlikely (!node))
463    return shape_plan;
464
465  node->shape_plan = shape_plan;
466  node->next = cached_plan_nodes;
467
468  if (!hb_atomic_ptr_cmpexch (&face->shape_plans, cached_plan_nodes, node)) {
469    hb_shape_plan_destroy (shape_plan);
470    free (node);
471    goto retry;
472  }
473  DEBUG_MSG_FUNC (SHAPE_PLAN, shape_plan, "inserted into cache");
474
475  return hb_shape_plan_reference (shape_plan);
476}
477
478/**
479 * hb_shape_plan_get_shaper:
480 * @shape_plan: a shape plan.
481 *
482 *
483 *
484 * Return value: (transfer none):
485 *
486 * Since: 1.0
487 **/
488const char *
489hb_shape_plan_get_shaper (hb_shape_plan_t *shape_plan)
490{
491  return shape_plan->shaper_name;
492}
493