summaryrefslogtreecommitdiff
path: root/Build/source/libs/harfbuzz/harfbuzz-src/src/hb-ot-map.cc
blob: e4bb4b6366194fed260a0be953c955c91d086dda (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
/*
 * Copyright © 2009,2010  Red Hat, Inc.
 * Copyright © 2010,2011,2013  Google, Inc.
 *
 *  This is part of HarfBuzz, a text shaping library.
 *
 * Permission is hereby granted, without written agreement and without
 * license or royalty fees, to use, copy, modify, and distribute this
 * software and its documentation for any purpose, provided that the
 * above copyright notice and the following two paragraphs appear in
 * all copies of this software.
 *
 * IN NO EVENT SHALL THE COPYRIGHT HOLDER BE LIABLE TO ANY PARTY FOR
 * DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES
 * ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN
 * IF THE COPYRIGHT HOLDER HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH
 * DAMAGE.
 *
 * THE COPYRIGHT HOLDER SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING,
 * BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
 * FITNESS FOR A PARTICULAR PURPOSE.  THE SOFTWARE PROVIDED HEREUNDER IS
 * ON AN "AS IS" BASIS, AND THE COPYRIGHT HOLDER HAS NO OBLIGATION TO
 * PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.
 *
 * Red Hat Author(s): Behdad Esfahbod
 * Google Author(s): Behdad Esfahbod
 */

#include "hb.hh"

#ifndef HB_NO_OT_SHAPE

#include "hb-ot-map.hh"
#include "hb-ot-shape.hh"
#include "hb-ot-layout.hh"


void hb_ot_map_t::collect_lookups (unsigned int table_index, hb_set_t *lookups_out) const
{
  for (unsigned int i = 0; i < lookups[table_index].length; i++)
    lookups_out->add (lookups[table_index][i].index);
}


hb_ot_map_builder_t::hb_ot_map_builder_t (hb_face_t *face_,
					  const hb_segment_properties_t *props_)
{
  memset (this, 0, sizeof (*this));

  feature_infos.init ();
  for (unsigned int table_index = 0; table_index < 2; table_index++)
    stages[table_index].init ();

  face = face_;
  props = *props_;


  /* Fetch script/language indices for GSUB/GPOS.  We need these later to skip
   * features not available in either table and not waste precious bits for them. */

  unsigned int script_count = HB_OT_MAX_TAGS_PER_SCRIPT;
  unsigned int language_count = HB_OT_MAX_TAGS_PER_LANGUAGE;
  hb_tag_t script_tags[HB_OT_MAX_TAGS_PER_SCRIPT];
  hb_tag_t language_tags[HB_OT_MAX_TAGS_PER_LANGUAGE];

  hb_ot_tags_from_script_and_language (props.script, props.language, &script_count, script_tags, &language_count, language_tags);

  for (unsigned int table_index = 0; table_index < 2; table_index++) {
    hb_tag_t table_tag = table_tags[table_index];
    found_script[table_index] = (bool) hb_ot_layout_table_select_script (face, table_tag, script_count, script_tags, &script_index[table_index], &chosen_script[table_index]);
    hb_ot_layout_script_select_language (face, table_tag, script_index[table_index], language_count, language_tags, &language_index[table_index]);
  }
}

hb_ot_map_builder_t::~hb_ot_map_builder_t ()
{
  feature_infos.fini ();
  for (unsigned int table_index = 0; table_index < 2; table_index++)
    stages[table_index].fini ();
}

void hb_ot_map_builder_t::add_feature (hb_tag_t tag,
				       hb_ot_map_feature_flags_t flags,
				       unsigned int value)
{
  if (unlikely (!tag)) return;
  feature_info_t *info = feature_infos.push();
  info->tag = tag;
  info->seq = feature_infos.length;
  info->max_value = value;
  info->flags = flags;
  info->default_value = (flags & F_GLOBAL) ? value : 0;
  info->stage[0] = current_stage[0];
  info->stage[1] = current_stage[1];
}

void
hb_ot_map_builder_t::add_lookups (hb_ot_map_t  &m,
				  unsigned int  table_index,
				  unsigned int  feature_index,
				  unsigned int  variations_index,
				  hb_mask_t     mask,
				  bool          auto_zwnj,
				  bool          auto_zwj,
				  bool          random)
{
  unsigned int lookup_indices[32];
  unsigned int offset, len;
  unsigned int table_lookup_count;

  table_lookup_count = hb_ot_layout_table_get_lookup_count (face, table_tags[table_index]);

  offset = 0;
  do {
    len = ARRAY_LENGTH (lookup_indices);
    hb_ot_layout_feature_with_variations_get_lookups (face,
						      table_tags[table_index],
						      feature_index,
						      variations_index,
						      offset, &len,
						      lookup_indices);

    for (unsigned int i = 0; i < len; i++)
    {
      if (lookup_indices[i] >= table_lookup_count)
	continue;
      hb_ot_map_t::lookup_map_t *lookup = m.lookups[table_index].push ();
      lookup->mask = mask;
      lookup->index = lookup_indices[i];
      lookup->auto_zwnj = auto_zwnj;
      lookup->auto_zwj = auto_zwj;
      lookup->random = random;
    }

    offset += len;
  } while (len == ARRAY_LENGTH (lookup_indices));
}


void hb_ot_map_builder_t::add_pause (unsigned int table_index, hb_ot_map_t::pause_func_t pause_func)
{
  stage_info_t *s = stages[table_index].push ();
  s->index = current_stage[table_index];
  s->pause_func = pause_func;

  current_stage[table_index]++;
}

void
hb_ot_map_builder_t::compile (hb_ot_map_t                  &m,
			      const hb_ot_shape_plan_key_t &key)
{
  static_assert ((!(HB_GLYPH_FLAG_DEFINED & (HB_GLYPH_FLAG_DEFINED + 1))), "");
  unsigned int global_bit_mask = HB_GLYPH_FLAG_DEFINED + 1;
  unsigned int global_bit_shift = hb_popcount (HB_GLYPH_FLAG_DEFINED);

  m.global_mask = global_bit_mask;

  unsigned int required_feature_index[2];
  hb_tag_t required_feature_tag[2];
  /* We default to applying required feature in stage 0.  If the required
   * feature has a tag that is known to the shaper, we apply required feature
   * in the stage for that tag.
   */
  unsigned int required_feature_stage[2] = {0, 0};

  for (unsigned int table_index = 0; table_index < 2; table_index++)
  {
    m.chosen_script[table_index] = chosen_script[table_index];
    m.found_script[table_index] = found_script[table_index];

    hb_ot_layout_language_get_required_feature (face,
						table_tags[table_index],
						script_index[table_index],
						language_index[table_index],
						&required_feature_index[table_index],
						&required_feature_tag[table_index]);
  }

  /* Sort features and merge duplicates */
  if (feature_infos.length)
  {
    feature_infos.qsort ();
    unsigned int j = 0;
    for (unsigned int i = 1; i < feature_infos.length; i++)
      if (feature_infos[i].tag != feature_infos[j].tag)
	feature_infos[++j] = feature_infos[i];
      else {
	if (feature_infos[i].flags & F_GLOBAL) {
	  feature_infos[j].flags |= F_GLOBAL;
	  feature_infos[j].max_value = feature_infos[i].max_value;
	  feature_infos[j].default_value = feature_infos[i].default_value;
	} else {
	  if (feature_infos[j].flags & F_GLOBAL)
	    feature_infos[j].flags ^= F_GLOBAL;
	  feature_infos[j].max_value = hb_max (feature_infos[j].max_value, feature_infos[i].max_value);
	  /* Inherit default_value from j */
	}
	feature_infos[j].flags |= (feature_infos[i].flags & F_HAS_FALLBACK);
	feature_infos[j].stage[0] = hb_min (feature_infos[j].stage[0], feature_infos[i].stage[0]);
	feature_infos[j].stage[1] = hb_min (feature_infos[j].stage[1], feature_infos[i].stage[1]);
      }
    feature_infos.shrink (j + 1);
  }


  /* Allocate bits now */
  unsigned int next_bit = global_bit_shift + 1;

  for (unsigned int i = 0; i < feature_infos.length; i++)
  {
    const feature_info_t *info = &feature_infos[i];

    unsigned int bits_needed;

    if ((info->flags & F_GLOBAL) && info->max_value == 1)
      /* Uses the global bit */
      bits_needed = 0;
    else
      /* Limit bits per feature. */
      bits_needed = hb_min (HB_OT_MAP_MAX_BITS, hb_bit_storage (info->max_value));

    if (!info->max_value || next_bit + bits_needed > 8 * sizeof (hb_mask_t))
      continue; /* Feature disabled, or not enough bits. */


    bool found = false;
    unsigned int feature_index[2];
    for (unsigned int table_index = 0; table_index < 2; table_index++)
    {
      if (required_feature_tag[table_index] == info->tag)
	required_feature_stage[table_index] = info->stage[table_index];

      found |= (bool) hb_ot_layout_language_find_feature (face,
							  table_tags[table_index],
							  script_index[table_index],
							  language_index[table_index],
							  info->tag,
							  &feature_index[table_index]);
    }
    if (!found && (info->flags & F_GLOBAL_SEARCH))
    {
      for (unsigned int table_index = 0; table_index < 2; table_index++)
      {
	found |= (bool) hb_ot_layout_table_find_feature (face,
							 table_tags[table_index],
							 info->tag,
							 &feature_index[table_index]);
      }
    }
    if (!found && !(info->flags & F_HAS_FALLBACK))
      continue;


    hb_ot_map_t::feature_map_t *map = m.features.push ();

    map->tag = info->tag;
    map->index[0] = feature_index[0];
    map->index[1] = feature_index[1];
    map->stage[0] = info->stage[0];
    map->stage[1] = info->stage[1];
    map->auto_zwnj = !(info->flags & F_MANUAL_ZWNJ);
    map->auto_zwj = !(info->flags & F_MANUAL_ZWJ);
    map->random = !!(info->flags & F_RANDOM);
    if ((info->flags & F_GLOBAL) && info->max_value == 1) {
      /* Uses the global bit */
      map->shift = global_bit_shift;
      map->mask = global_bit_mask;
    } else {
      map->shift = next_bit;
      map->mask = (1u << (next_bit + bits_needed)) - (1u << next_bit);
      next_bit += bits_needed;
      m.global_mask |= (info->default_value << map->shift) & map->mask;
    }
    map->_1_mask = (1u << map->shift) & map->mask;
    map->needs_fallback = !found;

  }
  feature_infos.shrink (0); /* Done with these */


  add_gsub_pause (nullptr);
  add_gpos_pause (nullptr);

  for (unsigned int table_index = 0; table_index < 2; table_index++)
  {
    /* Collect lookup indices for features */

    unsigned int stage_index = 0;
    unsigned int last_num_lookups = 0;
    for (unsigned stage = 0; stage < current_stage[table_index]; stage++)
    {
      if (required_feature_index[table_index] != HB_OT_LAYOUT_NO_FEATURE_INDEX &&
	  required_feature_stage[table_index] == stage)
	add_lookups (m, table_index,
		     required_feature_index[table_index],
		     key.variations_index[table_index],
		     global_bit_mask);

      for (unsigned i = 0; i < m.features.length; i++)
	if (m.features[i].stage[table_index] == stage)
	  add_lookups (m, table_index,
		       m.features[i].index[table_index],
		       key.variations_index[table_index],
		       m.features[i].mask,
		       m.features[i].auto_zwnj,
		       m.features[i].auto_zwj,
		       m.features[i].random);

      /* Sort lookups and merge duplicates */
      if (last_num_lookups < m.lookups[table_index].length)
      {
	m.lookups[table_index].qsort (last_num_lookups, m.lookups[table_index].length);

	unsigned int j = last_num_lookups;
	for (unsigned int i = j + 1; i < m.lookups[table_index].length; i++)
	  if (m.lookups[table_index][i].index != m.lookups[table_index][j].index)
	    m.lookups[table_index][++j] = m.lookups[table_index][i];
	  else
	  {
	    m.lookups[table_index][j].mask |= m.lookups[table_index][i].mask;
	    m.lookups[table_index][j].auto_zwnj &= m.lookups[table_index][i].auto_zwnj;
	    m.lookups[table_index][j].auto_zwj &= m.lookups[table_index][i].auto_zwj;
	  }
	m.lookups[table_index].shrink (j + 1);
      }

      last_num_lookups = m.lookups[table_index].length;

      if (stage_index < stages[table_index].length && stages[table_index][stage_index].index == stage) {
	hb_ot_map_t::stage_map_t *stage_map = m.stages[table_index].push ();
	stage_map->last_lookup = last_num_lookups;
	stage_map->pause_func = stages[table_index][stage_index].pause_func;

	stage_index++;
      }
    }
  }
}


#endif