harfbuzz: check in harfbuzz-ng, add gyp define to use it

third_party/harfbuzz-ng/src/hb-ot-map.cc

+/*
+ * 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,
+                          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];
+  }
+}
+
+
+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;
+
+  }
+  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, 1);
+
+    for (unsigned i = 0; i < feature_count; i++)
+      add_lookups (face, 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