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
38void 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
45hb_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
58 /* Fetch script/language indices for GSUB/GPOS. We need these later to skip
59 * features not available in either table and not waste precious bits for them. */
60
61 unsigned int script_count = HB_OT_MAX_TAGS_PER_SCRIPT;
62 unsigned int language_count = HB_OT_MAX_TAGS_PER_LANGUAGE;
63 hb_tag_t script_tags[HB_OT_MAX_TAGS_PER_SCRIPT];
64 hb_tag_t language_tags[HB_OT_MAX_TAGS_PER_LANGUAGE];
65
66 hb_ot_tags_from_script_and_language (props.script, props.language, &script_count, script_tags, &language_count, language_tags);
67
68 for (unsigned int table_index = 0; table_index < 2; table_index++) {
69 hb_tag_t table_tag = table_tags[table_index];
70 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]);
71 hb_ot_layout_script_select_language (face, table_tag, script_index[table_index], language_count, language_tags, &language_index[table_index]);
72 }
73}
74
75hb_ot_map_builder_t::~hb_ot_map_builder_t ()
76{
77 feature_infos.fini ();
78 for (unsigned int table_index = 0; table_index < 2; table_index++)
79 stages[table_index].fini ();
80}
81
82void hb_ot_map_builder_t::add_feature (hb_tag_t tag,
83 hb_ot_map_feature_flags_t flags,
84 unsigned int value)
85{
86 if (unlikely (!tag)) return;
87 feature_info_t *info = feature_infos.push();
88 info->tag = tag;
89 info->seq = feature_infos.length;
90 info->max_value = value;
91 info->flags = flags;
92 info->default_value = (flags & F_GLOBAL) ? value : 0;
93 info->stage[0] = current_stage[0];
94 info->stage[1] = current_stage[1];
95}
96
97void
98hb_ot_map_builder_t::add_lookups (hb_ot_map_t &m,
99 unsigned int table_index,
100 unsigned int feature_index,
101 unsigned int variations_index,
102 hb_mask_t mask,
103 bool auto_zwnj,
104 bool auto_zwj,
105 bool random)
106{
107 unsigned int lookup_indices[32];
108 unsigned int offset, len;
109 unsigned int table_lookup_count;
110
111 table_lookup_count = hb_ot_layout_table_get_lookup_count (face, table_tags[table_index]);
112
113 offset = 0;
114 do {
115 len = ARRAY_LENGTH (lookup_indices);
116 hb_ot_layout_feature_with_variations_get_lookups (face,
117 table_tags[table_index],
118 feature_index,
119 variations_index,
120 offset, &len,
121 lookup_indices);
122
123 for (unsigned int i = 0; i < len; i++)
124 {
125 if (lookup_indices[i] >= table_lookup_count)
126 continue;
127 hb_ot_map_t::lookup_map_t *lookup = m.lookups[table_index].push ();
128 lookup->mask = mask;
129 lookup->index = lookup_indices[i];
130 lookup->auto_zwnj = auto_zwnj;
131 lookup->auto_zwj = auto_zwj;
132 lookup->random = random;
133 }
134
135 offset += len;
136 } while (len == ARRAY_LENGTH (lookup_indices));
137}
138
139
140void hb_ot_map_builder_t::add_pause (unsigned int table_index, hb_ot_map_t::pause_func_t pause_func)
141{
142 stage_info_t *s = stages[table_index].push ();
143 s->index = current_stage[table_index];
144 s->pause_func = pause_func;
145
146 current_stage[table_index]++;
147}
148
149void
150hb_ot_map_builder_t::compile (hb_ot_map_t &m,
151 const hb_ot_shape_plan_key_t &key)
152{
153 static_assert ((!(HB_GLYPH_FLAG_DEFINED & (HB_GLYPH_FLAG_DEFINED + 1))), "");
154 unsigned int global_bit_mask = HB_GLYPH_FLAG_DEFINED + 1;
155 unsigned int global_bit_shift = hb_popcount (HB_GLYPH_FLAG_DEFINED);
156
157 m.global_mask = global_bit_mask;
158
159 unsigned int required_feature_index[2];
160 hb_tag_t required_feature_tag[2];
161 /* We default to applying required feature in stage 0. If the required
162 * feature has a tag that is known to the shaper, we apply required feature
163 * in the stage for that tag.
164 */
165 unsigned int required_feature_stage[2] = {0, 0};
166
167 for (unsigned int table_index = 0; table_index < 2; table_index++)
168 {
169 m.chosen_script[table_index] = chosen_script[table_index];
170 m.found_script[table_index] = found_script[table_index];
171
172 hb_ot_layout_language_get_required_feature (face,
173 table_tags[table_index],
174 script_index[table_index],
175 language_index[table_index],
176 &required_feature_index[table_index],
177 &required_feature_tag[table_index]);
178 }
179
180 /* Sort features and merge duplicates */
181 if (feature_infos.length)
182 {
183 feature_infos.qsort ();
184 unsigned int j = 0;
185 for (unsigned int i = 1; i < feature_infos.length; i++)
186 if (feature_infos[i].tag != feature_infos[j].tag)
187 feature_infos[++j] = feature_infos[i];
188 else {
189 if (feature_infos[i].flags & F_GLOBAL) {
190 feature_infos[j].flags |= F_GLOBAL;
191 feature_infos[j].max_value = feature_infos[i].max_value;
192 feature_infos[j].default_value = feature_infos[i].default_value;
193 } else {
194 if (feature_infos[j].flags & F_GLOBAL)
195 feature_infos[j].flags ^= F_GLOBAL;
196 feature_infos[j].max_value = hb_max (feature_infos[j].max_value, feature_infos[i].max_value);
197 /* Inherit default_value from j */
198 }
199 feature_infos[j].flags |= (feature_infos[i].flags & F_HAS_FALLBACK);
200 feature_infos[j].stage[0] = hb_min (feature_infos[j].stage[0], feature_infos[i].stage[0]);
201 feature_infos[j].stage[1] = hb_min (feature_infos[j].stage[1], feature_infos[i].stage[1]);
202 }
203 feature_infos.shrink (j + 1);
204 }
205
206
207 /* Allocate bits now */
208 unsigned int next_bit = global_bit_shift + 1;
209
210 for (unsigned int i = 0; i < feature_infos.length; i++)
211 {
212 const feature_info_t *info = &feature_infos[i];
213
214 unsigned int bits_needed;
215
216 if ((info->flags & F_GLOBAL) && info->max_value == 1)
217 /* Uses the global bit */
218 bits_needed = 0;
219 else
220 /* Limit bits per feature. */
221 bits_needed = hb_min (HB_OT_MAP_MAX_BITS, hb_bit_storage (info->max_value));
222
223 if (!info->max_value || next_bit + bits_needed > 8 * sizeof (hb_mask_t))
224 continue; /* Feature disabled, or not enough bits. */
225
226
227 bool found = false;
228 unsigned int feature_index[2];
229 for (unsigned int table_index = 0; table_index < 2; table_index++)
230 {
231 if (required_feature_tag[table_index] == info->tag)
232 required_feature_stage[table_index] = info->stage[table_index];
233
234 found |= (bool) hb_ot_layout_language_find_feature (face,
235 table_tags[table_index],
236 script_index[table_index],
237 language_index[table_index],
238 info->tag,
239 &feature_index[table_index]);
240 }
241 if (!found && (info->flags & F_GLOBAL_SEARCH))
242 {
243 for (unsigned int table_index = 0; table_index < 2; table_index++)
244 {
245 found |= (bool) hb_ot_layout_table_find_feature (face,
246 table_tags[table_index],
247 info->tag,
248 &feature_index[table_index]);
249 }
250 }
251 if (!found && !(info->flags & F_HAS_FALLBACK))
252 continue;
253
254
255 hb_ot_map_t::feature_map_t *map = m.features.push ();
256
257 map->tag = info->tag;
258 map->index[0] = feature_index[0];
259 map->index[1] = feature_index[1];
260 map->stage[0] = info->stage[0];
261 map->stage[1] = info->stage[1];
262 map->auto_zwnj = !(info->flags & F_MANUAL_ZWNJ);
263 map->auto_zwj = !(info->flags & F_MANUAL_ZWJ);
264 map->random = !!(info->flags & F_RANDOM);
265 if ((info->flags & F_GLOBAL) && info->max_value == 1) {
266 /* Uses the global bit */
267 map->shift = global_bit_shift;
268 map->mask = global_bit_mask;
269 } else {
270 map->shift = next_bit;
271 map->mask = (1u << (next_bit + bits_needed)) - (1u << next_bit);
272 next_bit += bits_needed;
273 m.global_mask |= (info->default_value << map->shift) & map->mask;
274 }
275 map->_1_mask = (1u << map->shift) & map->mask;
276 map->needs_fallback = !found;
277
278 }
279 feature_infos.shrink (0); /* Done with these */
280
281
282 add_gsub_pause (nullptr);
283 add_gpos_pause (nullptr);
284
285 for (unsigned int table_index = 0; table_index < 2; table_index++)
286 {
287 /* Collect lookup indices for features */
288
289 unsigned int stage_index = 0;
290 unsigned int last_num_lookups = 0;
291 for (unsigned stage = 0; stage < current_stage[table_index]; stage++)
292 {
293 if (required_feature_index[table_index] != HB_OT_LAYOUT_NO_FEATURE_INDEX &&
294 required_feature_stage[table_index] == stage)
295 add_lookups (m, table_index,
296 required_feature_index[table_index],
297 key.variations_index[table_index],
298 global_bit_mask);
299
300 for (unsigned i = 0; i < m.features.length; i++)
301 if (m.features[i].stage[table_index] == stage)
302 add_lookups (m, table_index,
303 m.features[i].index[table_index],
304 key.variations_index[table_index],
305 m.features[i].mask,
306 m.features[i].auto_zwnj,
307 m.features[i].auto_zwj,
308 m.features[i].random);
309
310 /* Sort lookups and merge duplicates */
311 if (last_num_lookups < m.lookups[table_index].length)
312 {
313 m.lookups[table_index].qsort (last_num_lookups, m.lookups[table_index].length);
314
315 unsigned int j = last_num_lookups;
316 for (unsigned int i = j + 1; i < m.lookups[table_index].length; i++)
317 if (m.lookups[table_index][i].index != m.lookups[table_index][j].index)
318 m.lookups[table_index][++j] = m.lookups[table_index][i];
319 else
320 {
321 m.lookups[table_index][j].mask |= m.lookups[table_index][i].mask;
322 m.lookups[table_index][j].auto_zwnj &= m.lookups[table_index][i].auto_zwnj;
323 m.lookups[table_index][j].auto_zwj &= m.lookups[table_index][i].auto_zwj;
324 }
325 m.lookups[table_index].shrink (j + 1);
326 }
327
328 last_num_lookups = m.lookups[table_index].length;
329
330 if (stage_index < stages[table_index].length && stages[table_index][stage_index].index == stage) {
331 hb_ot_map_t::stage_map_t *stage_map = m.stages[table_index].push ();
332 stage_map->last_lookup = last_num_lookups;
333 stage_map->pause_func = stages[table_index][stage_index].pause_func;
334
335 stage_index++;
336 }
337 }
338 }
339}
340
341
342#endif
343