2 * Copyright (C) 2009,2010 Red Hat, Inc.
3 * Copyright (C) 2010 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 i = MAX_LOOKUPS - lookup_count[table_index];
43 lookup_map_t *lookups = lookup_maps[table_index] + lookup_count[table_index];
45 unsigned int *lookup_indices = (unsigned int *) lookups;
47 hb_ot_layout_feature_get_lookup_indexes (face,
48 table_tags[table_index],
53 lookup_count[table_index] += i;
56 lookups[i].mask = mask;
57 lookups[i].index = lookup_indices[i];
63 hb_ot_map_t::compile (hb_face_t *face,
64 hb_segment_properties_t *props)
67 lookup_count[0] = lookup_count[1] = 0;
73 /* Fetch script/language indices for GSUB/GPOS. We need these later to skip
74 * features not available in either table and not waste precious bits for them. */
76 const hb_tag_t *script_tags;
77 hb_tag_t language_tag;
79 script_tags = hb_ot_tags_from_script (props->script);
80 language_tag = hb_ot_tag_from_language (props->language);
82 unsigned int script_index[2], language_index[2];
83 for (unsigned int table_index = 0; table_index < 2; table_index++) {
84 hb_tag_t table_tag = table_tags[table_index];
85 hb_ot_layout_table_choose_script (face, table_tag, script_tags, &script_index[table_index]);
86 hb_ot_layout_script_find_language (face, table_tag, script_index[table_index], language_tag, &language_index[table_index]);
90 /* Sort features and merge duplicates */
91 qsort (feature_infos, feature_count, sizeof (feature_infos[0]), (hb_compare_func_t) feature_info_t::cmp);
93 for (unsigned int i = 1; i < feature_count; i++)
94 if (feature_infos[i].tag != feature_infos[j].tag)
95 feature_infos[++j] = feature_infos[i];
97 if (feature_infos[i].global)
98 feature_infos[j] = feature_infos[i];
100 feature_infos[j].global = false;
101 feature_infos[j].value = MAX (feature_infos[j].value, feature_infos[i].value);
104 feature_count = j + 1;
107 /* Allocate bits now */
108 unsigned int next_bit = 1;
110 for (unsigned int i = 0; i < feature_count; i++) {
111 const feature_info_t *info = &feature_infos[i];
113 unsigned int bits_needed;
115 if (info->global && info->value == 1)
116 /* Uses the global bit */
119 bits_needed = _hb_bit_storage (info->value);
121 if (!info->value || next_bit + bits_needed > 8 * sizeof (hb_mask_t))
122 continue; /* Feature disabled, or not enough bits. */
126 unsigned int feature_index[2];
127 for (unsigned int table_index = 0; table_index < 2; table_index++)
128 found |= hb_ot_layout_language_find_feature (face,
129 table_tags[table_index],
130 script_index[table_index],
131 language_index[table_index],
133 &feature_index[table_index]);
138 feature_map_t *map = &feature_maps[j++];
140 map->tag = info->tag;
141 map->index[0] = feature_index[0];
142 map->index[1] = feature_index[1];
143 if (info->global && info->value == 1) {
144 /* Uses the global bit */
148 map->shift = next_bit;
149 map->mask = (1 << (next_bit + bits_needed)) - (1 << next_bit);
150 next_bit += bits_needed;
152 global_mask |= map->mask;
159 for (unsigned int table_index = 0; table_index < 2; table_index++) {
160 hb_tag_t table_tag = table_tags[table_index];
162 /* Collect lookup indices for features */
164 unsigned int required_feature_index;
165 if (hb_ot_layout_language_get_required_feature_index (face,
167 script_index[table_index],
168 language_index[table_index],
169 &required_feature_index))
170 add_lookups (face, table_index, required_feature_index, 1);
172 for (unsigned i = 0; i < feature_count; i++)
173 add_lookups (face, table_index, feature_maps[i].index[table_index], feature_maps[i].mask);
175 /* Sort lookups and merge duplicates */
176 qsort (lookup_maps[table_index], lookup_count[table_index], sizeof (lookup_maps[table_index][0]), (hb_compare_func_t) lookup_map_t::cmp);
177 if (lookup_count[table_index])
180 for (unsigned int i = 1; i < lookup_count[table_index]; i++)
181 if (lookup_maps[table_index][i].index != lookup_maps[table_index][j].index)
182 lookup_maps[table_index][++j] = lookup_maps[table_index][i];
184 lookup_maps[table_index][j].mask |= lookup_maps[table_index][i].mask;
186 lookup_count[table_index] = j;