2 * Copyright © 2009,2010 Red Hat, Inc.
3 * Copyright © 2010,2011 Google, Inc.
5 * This is part of HarfBuzz, a text shaping library.
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.
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
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.
25 * Red Hat Author(s): Behdad Esfahbod
26 * Google Author(s): Behdad Esfahbod
29 #include "hb-ot-map-private.hh"
31 #include "hb-ot-shape-private.hh"
37 hb_ot_map_t::add_lookups (hb_face_t *face,
38 unsigned int table_index,
39 unsigned int feature_index,
42 unsigned int lookup_indices[32];
43 unsigned int offset, len;
47 len = ARRAY_LENGTH (lookup_indices);
48 hb_ot_layout_feature_get_lookup_indexes (face,
49 table_tags[table_index],
54 for (unsigned int i = 0; i < len; i++) {
55 hb_ot_map_t::lookup_map_t *lookup = lookups[table_index].push ();
56 if (unlikely (!lookup))
59 lookup->index = lookup_indices[i];
63 } while (len == ARRAY_LENGTH (lookup_indices));
67 void hb_ot_map_builder_t::add_feature (hb_tag_t tag, unsigned int value, bool global)
69 feature_info_t *info = feature_infos.push();
70 if (unlikely (!info)) return;
72 info->seq = feature_infos.len;
73 info->max_value = value;
74 info->global = global;
75 info->default_value = global ? value : 0;
76 info->stage[0] = current_stage[0];
77 info->stage[1] = current_stage[1];
80 void hb_ot_map_t::apply (unsigned int table_index,
81 hb_ot_map_t::apply_lookup_func_t apply_lookup_func,
83 hb_buffer_t *buffer) const
87 for (unsigned int pause_index = 0; pause_index < pauses[table_index].len; pause_index++) {
88 const pause_map_t *pause = &pauses[table_index][pause_index];
89 for (; i < pause->num_lookups; i++)
90 apply_lookup_func (face_or_font, buffer, lookups[table_index][i].index, lookups[table_index][i].mask);
92 pause->callback.func (this, face_or_font, buffer, pause->callback.user_data);
95 for (; i < lookups[table_index].len; i++)
96 apply_lookup_func (face_or_font, buffer, lookups[table_index][i].index, lookups[table_index][i].mask);
100 void hb_ot_map_builder_t::add_pause (unsigned int table_index, hb_ot_map_t::pause_func_t pause_func, void *user_data)
103 pause_info_t *p = pauses[table_index].push ();
105 p->stage = current_stage[table_index];
106 p->callback.func = pause_func;
107 p->callback.user_data = user_data;
111 current_stage[table_index]++;
115 hb_ot_map_builder_t::compile (hb_face_t *face,
116 const hb_segment_properties_t *props,
121 if (!feature_infos.len)
125 /* Fetch script/language indices for GSUB/GPOS. We need these later to skip
126 * features not available in either table and not waste precious bits for them. */
128 hb_tag_t script_tags[3] = {HB_TAG_NONE};
129 hb_tag_t language_tag;
131 hb_ot_tags_from_script (props->script, &script_tags[0], &script_tags[1]);
132 language_tag = hb_ot_tag_from_language (props->language);
134 unsigned int script_index[2], language_index[2];
135 for (unsigned int table_index = 0; table_index < 2; table_index++) {
136 hb_tag_t table_tag = table_tags[table_index];
137 hb_ot_layout_table_choose_script (face, table_tag, script_tags, &script_index[table_index], &m.chosen_script[table_index]);
138 hb_ot_layout_script_find_language (face, table_tag, script_index[table_index], language_tag, &language_index[table_index]);
142 /* Sort features and merge duplicates */
144 feature_infos.sort ();
146 for (unsigned int i = 1; i < feature_infos.len; i++)
147 if (feature_infos[i].tag != feature_infos[j].tag)
148 feature_infos[++j] = feature_infos[i];
150 if (feature_infos[i].global) {
151 feature_infos[j].global = true;
152 feature_infos[j].max_value = feature_infos[i].max_value;
153 feature_infos[j].default_value = feature_infos[i].default_value;
155 feature_infos[j].global = false;
156 feature_infos[j].max_value = MAX (feature_infos[j].max_value, feature_infos[i].max_value);
158 feature_infos[j].stage[0] = MIN (feature_infos[j].stage[0], feature_infos[i].stage[0]);
159 feature_infos[j].stage[1] = MIN (feature_infos[j].stage[1], feature_infos[i].stage[1]);
160 /* Inherit default_value from j */
162 feature_infos.shrink (j + 1);
166 /* Allocate bits now */
167 unsigned int next_bit = 1;
168 for (unsigned int i = 0; i < feature_infos.len; i++) {
169 const feature_info_t *info = &feature_infos[i];
171 unsigned int bits_needed;
173 if (info->global && info->max_value == 1)
174 /* Uses the global bit */
177 bits_needed = _hb_bit_storage (info->max_value);
179 if (!info->max_value || next_bit + bits_needed > 8 * sizeof (hb_mask_t))
180 continue; /* Feature disabled, or not enough bits. */
184 unsigned int feature_index[2];
185 for (unsigned int table_index = 0; table_index < 2; table_index++)
186 found |= hb_ot_layout_language_find_feature (face,
187 table_tags[table_index],
188 script_index[table_index],
189 language_index[table_index],
191 &feature_index[table_index]);
196 hb_ot_map_t::feature_map_t *map = m.features.push ();
200 map->tag = info->tag;
201 map->index[0] = feature_index[0];
202 map->index[1] = feature_index[1];
203 map->stage[0] = info->stage[0];
204 map->stage[1] = info->stage[1];
205 if (info->global && info->max_value == 1) {
206 /* Uses the global bit */
210 map->shift = next_bit;
211 map->mask = (1 << (next_bit + bits_needed)) - (1 << next_bit);
212 next_bit += bits_needed;
214 m.global_mask |= (info->default_value << map->shift) & map->mask;
216 map->_1_mask = (1 << map->shift) & map->mask;
219 feature_infos.shrink (0); /* Done with these */
222 add_gsub_pause (NULL, NULL);
223 add_gpos_pause (NULL, NULL);
225 for (unsigned int table_index = 0; table_index < 2; table_index++) {
226 hb_tag_t table_tag = table_tags[table_index];
228 /* Collect lookup indices for features */
230 unsigned int required_feature_index;
231 if (hb_ot_layout_language_get_required_feature_index (face,
233 script_index[table_index],
234 language_index[table_index],
235 &required_feature_index))
236 m.add_lookups (face, table_index, required_feature_index, 1);
238 unsigned int pause_index = 0;
239 unsigned int last_num_lookups = 0;
240 for (unsigned stage = 0; stage < current_stage[table_index]; stage++)
242 for (unsigned i = 0; i < m.features.len; i++)
243 if (m.features[i].stage[table_index] == stage)
244 m.add_lookups (face, table_index, m.features[i].index[table_index], m.features[i].mask);
246 /* Sort lookups and merge duplicates */
247 if (last_num_lookups < m.lookups[table_index].len)
249 m.lookups[table_index].sort (last_num_lookups, m.lookups[table_index].len);
251 unsigned int j = last_num_lookups;
252 for (unsigned int i = j + 1; i < m.lookups[table_index].len; i++)
253 if (m.lookups[table_index][i].index != m.lookups[table_index][j].index)
254 m.lookups[table_index][++j] = m.lookups[table_index][i];
256 m.lookups[table_index][j].mask |= m.lookups[table_index][i].mask;
257 m.lookups[table_index].shrink (j + 1);
260 last_num_lookups = m.lookups[table_index].len;
262 if (pause_index < pauses[table_index].len && pauses[table_index][pause_index].stage == stage) {
263 hb_ot_map_t::pause_map_t *pause_map = m.pauses[table_index].push ();
264 if (likely (pause_map)) {
265 pause_map->num_lookups = last_num_lookups;
266 pause_map->callback = pauses[table_index][pause_index].callback;