1 /*
2 * Copyright © 2009,2010 Red Hat, Inc.
3 * Copyright © 2010,2011,2013 Google, Inc.
4 *
5 * This is part of HarfBuzz, a text shaping library.
6 *
7 * Permission is hereby granted, without written agreement and without
8 * license or royalty fees, to use, copy, modify, and distribute this
9 * software and its documentation for any purpose, provided that the
10 * above copyright notice and the following two paragraphs appear in
11 * all copies of this software.
12 *
13 * IN NO EVENT SHALL THE COPYRIGHT HOLDER BE LIABLE TO ANY PARTY FOR
14 * DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES
15 * ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN
16 * IF THE COPYRIGHT HOLDER HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH
17 * DAMAGE.
18 *
19 * THE COPYRIGHT HOLDER SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING,
20 * BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
21 * FITNESS FOR A PARTICULAR PURPOSE. THE SOFTWARE PROVIDED HEREUNDER IS
22 * ON AN "AS IS" BASIS, AND THE COPYRIGHT HOLDER HAS NO OBLIGATION TO
23 * PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.
24 *
25 * Red Hat Author(s): Behdad Esfahbod
26 * Google Author(s): Behdad Esfahbod
27 */
28
29 #include "hb.hh"
30
31 #ifndef HB_NO_OT_SHAPE
32
33 #include "hb-ot-map.hh"
34 #include "hb-ot-shape.hh"
35 #include "hb-ot-layout.hh"
36
37
collect_lookups(unsigned int table_index,hb_set_t * lookups_out) const38 void hb_ot_map_t::collect_lookups (unsigned int table_index, hb_set_t *lookups_out) const
39 {
40 for (unsigned int i = 0; i < lookups[table_index].length; i++)
41 lookups_out->add (lookups[table_index][i].index);
42 }
43
44
hb_ot_map_builder_t(hb_face_t * face_,const hb_segment_properties_t * props_)45 hb_ot_map_builder_t::hb_ot_map_builder_t (hb_face_t *face_,
46 const hb_segment_properties_t *props_)
47 {
48 memset (this, 0, sizeof (*this));
49
50 feature_infos.init ();
51 for (unsigned int table_index = 0; table_index < 2; table_index++)
52 stages[table_index].init ();
53
54 face = face_;
55 props = *props_;
56
57 /* Fetch script/language indices for GSUB/GPOS. We need these later to skip
58 * features not available in either table and not waste precious bits for them. */
59
60 unsigned int script_count = HB_OT_MAX_TAGS_PER_SCRIPT;
61 unsigned int language_count = HB_OT_MAX_TAGS_PER_LANGUAGE;
62 hb_tag_t script_tags[HB_OT_MAX_TAGS_PER_SCRIPT];
63 hb_tag_t language_tags[HB_OT_MAX_TAGS_PER_LANGUAGE];
64
65 hb_ot_tags_from_script_and_language (props.script,
66 props.language,
67 &script_count,
68 script_tags,
69 &language_count,
70 language_tags);
71
72 for (unsigned int table_index = 0; table_index < 2; table_index++)
73 {
74 hb_tag_t table_tag = table_tags[table_index];
75 found_script[table_index] = (bool) hb_ot_layout_table_select_script (face,
76 table_tag,
77 script_count,
78 script_tags,
79 &script_index[table_index],
80 &chosen_script[table_index]);
81 hb_ot_layout_script_select_language (face,
82 table_tag,
83 script_index[table_index],
84 language_count,
85 language_tags,
86 &language_index[table_index]);
87 }
88 }
89
~hb_ot_map_builder_t()90 hb_ot_map_builder_t::~hb_ot_map_builder_t ()
91 {
92 feature_infos.fini ();
93 for (unsigned int table_index = 0; table_index < 2; table_index++)
94 stages[table_index].fini ();
95 }
96
add_feature(hb_tag_t tag,hb_ot_map_feature_flags_t flags,unsigned int value)97 void hb_ot_map_builder_t::add_feature (hb_tag_t tag,
98 hb_ot_map_feature_flags_t flags,
99 unsigned int value)
100 {
101 if (unlikely (!tag)) return;
102 feature_info_t *info = feature_infos.push();
103 info->tag = tag;
104 info->seq = feature_infos.length;
105 info->max_value = value;
106 info->flags = flags;
107 info->default_value = (flags & F_GLOBAL) ? value : 0;
108 info->stage[0] = current_stage[0];
109 info->stage[1] = current_stage[1];
110 }
111
112 void
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)113 hb_ot_map_builder_t::add_lookups (hb_ot_map_t &m,
114 unsigned int table_index,
115 unsigned int feature_index,
116 unsigned int variations_index,
117 hb_mask_t mask,
118 bool auto_zwnj,
119 bool auto_zwj,
120 bool random)
121 {
122 unsigned int lookup_indices[32];
123 unsigned int offset, len;
124 unsigned int table_lookup_count;
125
126 table_lookup_count = hb_ot_layout_table_get_lookup_count (face, table_tags[table_index]);
127
128 offset = 0;
129 do {
130 len = ARRAY_LENGTH (lookup_indices);
131 hb_ot_layout_feature_with_variations_get_lookups (face,
132 table_tags[table_index],
133 feature_index,
134 variations_index,
135 offset, &len,
136 lookup_indices);
137
138 for (unsigned int i = 0; i < len; i++)
139 {
140 if (lookup_indices[i] >= table_lookup_count)
141 continue;
142 hb_ot_map_t::lookup_map_t *lookup = m.lookups[table_index].push ();
143 lookup->mask = mask;
144 lookup->index = lookup_indices[i];
145 lookup->auto_zwnj = auto_zwnj;
146 lookup->auto_zwj = auto_zwj;
147 lookup->random = random;
148 }
149
150 offset += len;
151 } while (len == ARRAY_LENGTH (lookup_indices));
152 }
153
154
add_pause(unsigned int table_index,hb_ot_map_t::pause_func_t pause_func)155 void hb_ot_map_builder_t::add_pause (unsigned int table_index, hb_ot_map_t::pause_func_t pause_func)
156 {
157 stage_info_t *s = stages[table_index].push ();
158 s->index = current_stage[table_index];
159 s->pause_func = pause_func;
160
161 current_stage[table_index]++;
162 }
163
164 void
compile(hb_ot_map_t & m,const hb_ot_shape_plan_key_t & key)165 hb_ot_map_builder_t::compile (hb_ot_map_t &m,
166 const hb_ot_shape_plan_key_t &key)
167 {
168 unsigned int global_bit_shift = 8 * sizeof (hb_mask_t) - 1;
169 unsigned int global_bit_mask = 1u << global_bit_shift;
170
171 m.global_mask = global_bit_mask;
172
173 unsigned int required_feature_index[2];
174 hb_tag_t required_feature_tag[2];
175 /* We default to applying required feature in stage 0. If the required
176 * feature has a tag that is known to the shaper, we apply required feature
177 * in the stage for that tag.
178 */
179 unsigned int required_feature_stage[2] = {0, 0};
180
181 for (unsigned int table_index = 0; table_index < 2; table_index++)
182 {
183 m.chosen_script[table_index] = chosen_script[table_index];
184 m.found_script[table_index] = found_script[table_index];
185
186 hb_ot_layout_language_get_required_feature (face,
187 table_tags[table_index],
188 script_index[table_index],
189 language_index[table_index],
190 &required_feature_index[table_index],
191 &required_feature_tag[table_index]);
192 }
193
194 /* Sort features and merge duplicates */
195 if (feature_infos.length)
196 {
197 feature_infos.qsort ();
198 unsigned int j = 0;
199 for (unsigned int i = 1; i < feature_infos.length; i++)
200 if (feature_infos[i].tag != feature_infos[j].tag)
201 feature_infos[++j] = feature_infos[i];
202 else {
203 if (feature_infos[i].flags & F_GLOBAL) {
204 feature_infos[j].flags |= F_GLOBAL;
205 feature_infos[j].max_value = feature_infos[i].max_value;
206 feature_infos[j].default_value = feature_infos[i].default_value;
207 } else {
208 if (feature_infos[j].flags & F_GLOBAL)
209 feature_infos[j].flags ^= F_GLOBAL;
210 feature_infos[j].max_value = hb_max (feature_infos[j].max_value, feature_infos[i].max_value);
211 /* Inherit default_value from j */
212 }
213 feature_infos[j].flags |= (feature_infos[i].flags & F_HAS_FALLBACK);
214 feature_infos[j].stage[0] = hb_min (feature_infos[j].stage[0], feature_infos[i].stage[0]);
215 feature_infos[j].stage[1] = hb_min (feature_infos[j].stage[1], feature_infos[i].stage[1]);
216 }
217 feature_infos.shrink (j + 1);
218 }
219
220
221 /* Allocate bits now */
222 static_assert ((!(HB_GLYPH_FLAG_DEFINED & (HB_GLYPH_FLAG_DEFINED + 1))), "");
223 unsigned int next_bit = hb_popcount (HB_GLYPH_FLAG_DEFINED) + 1;
224
225 for (unsigned int i = 0; i < feature_infos.length; i++)
226 {
227 const feature_info_t *info = &feature_infos[i];
228
229 unsigned int bits_needed;
230
231 if ((info->flags & F_GLOBAL) && info->max_value == 1)
232 /* Uses the global bit */
233 bits_needed = 0;
234 else
235 /* Limit bits per feature. */
236 bits_needed = hb_min (HB_OT_MAP_MAX_BITS, hb_bit_storage (info->max_value));
237
238 if (!info->max_value || next_bit + bits_needed >= global_bit_shift)
239 continue; /* Feature disabled, or not enough bits. */
240
241
242 bool found = false;
243 unsigned int feature_index[2];
244 for (unsigned int table_index = 0; table_index < 2; table_index++)
245 {
246 if (required_feature_tag[table_index] == info->tag)
247 required_feature_stage[table_index] = info->stage[table_index];
248
249 found |= (bool) hb_ot_layout_language_find_feature (face,
250 table_tags[table_index],
251 script_index[table_index],
252 language_index[table_index],
253 info->tag,
254 &feature_index[table_index]);
255 }
256 if (!found && (info->flags & F_GLOBAL_SEARCH))
257 {
258 for (unsigned int table_index = 0; table_index < 2; table_index++)
259 {
260 found |= (bool) hb_ot_layout_table_find_feature (face,
261 table_tags[table_index],
262 info->tag,
263 &feature_index[table_index]);
264 }
265 }
266 if (!found && !(info->flags & F_HAS_FALLBACK))
267 continue;
268
269
270 hb_ot_map_t::feature_map_t *map = m.features.push ();
271
272 map->tag = info->tag;
273 map->index[0] = feature_index[0];
274 map->index[1] = feature_index[1];
275 map->stage[0] = info->stage[0];
276 map->stage[1] = info->stage[1];
277 map->auto_zwnj = !(info->flags & F_MANUAL_ZWNJ);
278 map->auto_zwj = !(info->flags & F_MANUAL_ZWJ);
279 map->random = !!(info->flags & F_RANDOM);
280 if ((info->flags & F_GLOBAL) && info->max_value == 1) {
281 /* Uses the global bit */
282 map->shift = global_bit_shift;
283 map->mask = global_bit_mask;
284 } else {
285 map->shift = next_bit;
286 map->mask = (1u << (next_bit + bits_needed)) - (1u << next_bit);
287 next_bit += bits_needed;
288 m.global_mask |= (info->default_value << map->shift) & map->mask;
289 }
290 map->_1_mask = (1u << map->shift) & map->mask;
291 map->needs_fallback = !found;
292 }
293 feature_infos.shrink (0); /* Done with these */
294
295
296 add_gsub_pause (nullptr);
297 add_gpos_pause (nullptr);
298
299 for (unsigned int table_index = 0; table_index < 2; table_index++)
300 {
301 /* Collect lookup indices for features */
302
303 unsigned int stage_index = 0;
304 unsigned int last_num_lookups = 0;
305 for (unsigned stage = 0; stage < current_stage[table_index]; stage++)
306 {
307 if (required_feature_index[table_index] != HB_OT_LAYOUT_NO_FEATURE_INDEX &&
308 required_feature_stage[table_index] == stage)
309 add_lookups (m, table_index,
310 required_feature_index[table_index],
311 key.variations_index[table_index],
312 global_bit_mask);
313
314 for (unsigned i = 0; i < m.features.length; i++)
315 if (m.features[i].stage[table_index] == stage)
316 add_lookups (m, table_index,
317 m.features[i].index[table_index],
318 key.variations_index[table_index],
319 m.features[i].mask,
320 m.features[i].auto_zwnj,
321 m.features[i].auto_zwj,
322 m.features[i].random);
323
324 /* Sort lookups and merge duplicates */
325 if (last_num_lookups < m.lookups[table_index].length)
326 {
327 m.lookups[table_index].qsort (last_num_lookups, m.lookups[table_index].length);
328
329 unsigned int j = last_num_lookups;
330 for (unsigned int i = j + 1; i < m.lookups[table_index].length; i++)
331 if (m.lookups[table_index][i].index != m.lookups[table_index][j].index)
332 m.lookups[table_index][++j] = m.lookups[table_index][i];
333 else
334 {
335 m.lookups[table_index][j].mask |= m.lookups[table_index][i].mask;
336 m.lookups[table_index][j].auto_zwnj &= m.lookups[table_index][i].auto_zwnj;
337 m.lookups[table_index][j].auto_zwj &= m.lookups[table_index][i].auto_zwj;
338 }
339 m.lookups[table_index].shrink (j + 1);
340 }
341
342 last_num_lookups = m.lookups[table_index].length;
343
344 if (stage_index < stages[table_index].length && stages[table_index][stage_index].index == stage) {
345 hb_ot_map_t::stage_map_t *stage_map = m.stages[table_index].push ();
346 stage_map->last_lookup = last_num_lookups;
347 stage_map->pause_func = stages[table_index][stage_index].pause_func;
348
349 stage_index++;
350 }
351 }
352 }
353 }
354
355
356 #endif
357