/gfx/harfbuzz/src/hb-ot-map.cc
C++ | 196 lines | 123 code | 37 blank | 36 comment | 29 complexity | 8539e1c5e1cf29fa07b287412f492aa9 MD5 | raw file
Possible License(s): AGPL-1.0, MIT, BSD-3-Clause, Apache-2.0, LGPL-2.1, 0BSD, LGPL-3.0, MPL-2.0-no-copyleft-exception, GPL-2.0, JSON
- /*
- * Copyright (C) 2009,2010 Red Hat, Inc.
- * Copyright (C) 2010 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-ot-map-private.hh"
- #include "hb-ot-shape-private.hh"
- HB_BEGIN_DECLS
- void
- hb_ot_map_t::add_lookups (hb_face_t *face,
- unsigned int table_index,
- unsigned int feature_index,
- unsigned short priority,
- hb_mask_t mask)
- {
- unsigned int i = MAX_LOOKUPS - lookup_count[table_index];
- lookup_map_t *lookups = lookup_maps[table_index] + lookup_count[table_index];
- unsigned int *lookup_indices = (unsigned int *) lookups;
- hb_ot_layout_feature_get_lookup_indexes (face,
- table_tags[table_index],
- feature_index,
- 0, &i,
- lookup_indices);
- lookup_count[table_index] += i;
- while (i--) {
- lookups[i].mask = mask;
- lookups[i].index = lookup_indices[i];
- lookups[i].priority = priority;
- }
- }
- void
- hb_ot_map_t::compile (hb_face_t *face,
- const hb_segment_properties_t *props)
- {
- global_mask = 1;
- lookup_count[0] = lookup_count[1] = 0;
- if (!feature_count)
- return;
- /* 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. */
- const hb_tag_t *script_tags;
- hb_tag_t language_tag;
- script_tags = hb_ot_tags_from_script (props->script);
- language_tag = hb_ot_tag_from_language (props->language);
- unsigned int script_index[2], language_index[2];
- for (unsigned int table_index = 0; table_index < 2; table_index++) {
- hb_tag_t table_tag = table_tags[table_index];
- hb_ot_layout_table_choose_script (face, table_tag, script_tags, &script_index[table_index]);
- hb_ot_layout_script_find_language (face, table_tag, script_index[table_index], language_tag, &language_index[table_index]);
- }
- /* Sort features and merge duplicates */
- qsort (feature_infos, feature_count, sizeof (feature_infos[0]), (hb_compare_func_t) feature_info_t::cmp);
- unsigned int j = 0;
- for (unsigned int i = 1; i < feature_count; i++)
- if (feature_infos[i].tag != feature_infos[j].tag)
- feature_infos[++j] = feature_infos[i];
- else {
- if (feature_infos[i].global)
- feature_infos[j] = feature_infos[i];
- else {
- feature_infos[j].global = false;
- feature_infos[j].max_value = MAX (feature_infos[j].max_value, feature_infos[i].max_value);
- /* Inherit default_value from j */
- }
- }
- feature_count = j + 1;
- /* Allocate bits now */
- unsigned int next_bit = 1;
- j = 0;
- for (unsigned int i = 0; i < feature_count; i++) {
- const feature_info_t *info = &feature_infos[i];
- unsigned int bits_needed;
- if (info->global && info->max_value == 1)
- /* Uses the global bit */
- bits_needed = 0;
- else
- bits_needed = _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++)
- found |= 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)
- continue;
- feature_map_t *map = &feature_maps[j++];
- map->tag = info->tag;
- map->index[0] = feature_index[0];
- map->index[1] = feature_index[1];
- if (info->global && info->max_value == 1) {
- /* Uses the global bit */
- map->shift = 0;
- map->mask = 1;
- } else {
- map->shift = next_bit;
- map->mask = (1 << (next_bit + bits_needed)) - (1 << next_bit);
- next_bit += bits_needed;
- if (info->global)
- global_mask |= (info->default_value << map->shift) & map->mask;
- }
- map->_1_mask = (1 << map->shift) & map->mask;
- map->priority = info->priority;
- }
- feature_count = j;
- for (unsigned int table_index = 0; table_index < 2; table_index++) {
- hb_tag_t table_tag = table_tags[table_index];
- /* Collect lookup indices for features */
- unsigned int required_feature_index;
- if (hb_ot_layout_language_get_required_feature_index (face,
- table_tag,
- script_index[table_index],
- language_index[table_index],
- &required_feature_index))
- add_lookups (face, table_index, required_feature_index, DEFAULT_PRIORITY, 1);
- for (unsigned i = 0; i < feature_count; i++)
- add_lookups (face, table_index, feature_maps[i].index[table_index], feature_maps[i].priority, feature_maps[i].mask);
- /* Sort lookups and merge duplicates */
- qsort (lookup_maps[table_index], lookup_count[table_index], sizeof (lookup_maps[table_index][0]), (hb_compare_func_t) lookup_map_t::cmp);
- if (lookup_count[table_index])
- {
- unsigned int j = 0;
- for (unsigned int i = 1; i < lookup_count[table_index]; i++)
- if (lookup_maps[table_index][i].index != lookup_maps[table_index][j].index)
- lookup_maps[table_index][++j] = lookup_maps[table_index][i];
- else
- lookup_maps[table_index][j].mask |= lookup_maps[table_index][i].mask;
- j++;
- lookup_count[table_index] = j;
- }
- }
- }
- HB_END_DECLS