+/*
+ * 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_mask_allocator_t::compile (hb_ot_shape_context_t *c)
+{
+ global_mask = 0;
+ 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 (c->buffer->props.script);
+ language_tag = hb_ot_tag_from_language (c->buffer->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 (c->face, table_tag, script_tags, &script_index[table_index]);
+ hb_ot_layout_script_find_language (c->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].value = MAX (feature_infos[j].value, feature_infos[i].value);
+ }
+ }
+ 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->value == 1)
+ /* Uses the global bit */
+ bits_needed = 0;
+ else
+ bits_needed = _hb_bit_storage (info->value);
+
+ if (!info->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 (c->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->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 |= map->mask;
+ }
+
+ }
+ 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 (c->face,
+ table_tag,
+ script_index[table_index],
+ language_index[table_index],
+ &required_feature_index))
+ add_lookups (c, table_index, required_feature_index, 1);
+
+ for (unsigned i = 0; i < feature_count; i++)
+ add_lookups (c, table_index, feature_maps[i].index[table_index], 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