harfbuzz/src/hb-ot-map.cc

199 lines
6.0 KiB
C++
Raw Normal View History

2010-10-09 02:14:57 +02:00
/*
2011-04-21 23:14:28 +02:00
* Copyright © 2009,2010 Red Hat, Inc.
* Copyright © 2010 Google, Inc.
2010-10-09 02:14:57 +02:00
*
* 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
2010-10-12 22:00:21 +02:00
hb_ot_map_t::add_lookups (hb_face_t *face,
2010-10-12 21:35:45 +02:00
unsigned int table_index,
unsigned int feature_index,
hb_mask_t mask)
{
unsigned int lookup_indices[32];
unsigned int offset, len;
offset = 0;
do {
len = ARRAY_LENGTH (lookup_indices);
hb_ot_layout_feature_get_lookup_indexes (face,
table_tags[table_index],
feature_index,
offset, &len,
lookup_indices);
for (unsigned int i = 0; i < len; i++) {
lookup_map_t *lookup = lookup_maps[table_index].push ();
if (unlikely (!lookup))
return;
lookup->mask = mask;
lookup->index = lookup_indices[i];
}
2010-10-12 21:35:45 +02:00
offset += len;
} while (len == ARRAY_LENGTH (lookup_indices));
2010-10-12 21:35:45 +02:00
}
void
2010-10-12 22:00:21 +02:00
hb_ot_map_t::compile (hb_face_t *face,
const hb_segment_properties_t *props)
2010-10-09 02:14:57 +02:00
{
global_mask = 1;
2010-10-09 02:14:57 +02:00
if (!feature_infos.len)
2010-10-09 02:14:57 +02:00
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. */
hb_tag_t script_tags[3] = {HB_TAG_NONE};
2010-10-09 02:14:57 +02:00
hb_tag_t language_tag;
hb_ot_tags_from_script (props->script, &script_tags[0], &script_tags[1]);
2010-10-12 22:00:21 +02:00
language_tag = hb_ot_tag_from_language (props->language);
2010-10-09 02:14:57 +02:00
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];
2010-10-12 22:00:21 +02:00
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]);
2010-10-09 02:14:57 +02:00
}
/* Sort features and merge duplicates */
feature_infos.sort ();
2010-10-09 02:14:57 +02:00
unsigned int j = 0;
for (unsigned int i = 1; i < feature_infos.len; i++)
2010-10-09 02:14:57 +02:00
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 */
2010-10-09 02:14:57 +02:00
}
}
feature_infos.shrink (j + 1);
2010-10-09 02:14:57 +02:00
/* Allocate bits now */
unsigned int next_bit = 1;
for (unsigned int i = 0; i < feature_infos.len; i++) {
2010-10-09 02:14:57 +02:00
const feature_info_t *info = &feature_infos[i];
unsigned int bits_needed;
if (info->global && info->max_value == 1)
2010-10-09 02:14:57 +02:00
/* Uses the global bit */
bits_needed = 0;
else
bits_needed = _hb_bit_storage (info->max_value);
2010-10-09 02:14:57 +02:00
if (!info->max_value || next_bit + bits_needed > 8 * sizeof (hb_mask_t))
2010-10-09 02:14:57 +02:00
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++)
2010-10-12 22:00:21 +02:00
found |= hb_ot_layout_language_find_feature (face,
2010-10-09 02:14:57 +02:00
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.push ();
if (unlikely (!map))
break;
2010-10-09 02:14:57 +02:00
map->tag = info->tag;
map->index[0] = feature_index[0];
map->index[1] = feature_index[1];
if (info->global && info->max_value == 1) {
2010-10-09 02:14:57 +02:00
/* 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;
2010-10-09 02:14:57 +02:00
}
map->_1_mask = (1 << map->shift) & map->mask;
2010-10-09 02:14:57 +02:00
}
feature_infos.shrink (0); /* Done with these */
2010-10-09 02:14:57 +02:00
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;
2010-10-12 22:00:21 +02:00
if (hb_ot_layout_language_get_required_feature_index (face,
2010-10-09 02:14:57 +02:00
table_tag,
script_index[table_index],
language_index[table_index],
&required_feature_index))
2010-10-12 22:00:21 +02:00
add_lookups (face, table_index, required_feature_index, 1);
2010-10-09 02:14:57 +02:00
for (unsigned i = 0; i < feature_maps.len; i++)
2010-10-12 22:00:21 +02:00
add_lookups (face, table_index, feature_maps[i].index[table_index], feature_maps[i].mask);
2010-10-09 02:14:57 +02:00
/* Sort lookups and merge duplicates */
lookup_maps[table_index].sort ();
if (lookup_maps[table_index].len)
2010-10-09 02:14:57 +02:00
{
unsigned int j = 0;
for (unsigned int i = 1; i < lookup_maps[table_index].len; i++)
2010-10-09 02:14:57 +02:00
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;
lookup_maps[table_index].shrink (j + 1);
2010-10-09 02:14:57 +02:00
}
}
}
HB_END_DECLS