1 /*
2 * Copyright © 2009,2010 Red Hat, Inc.
3 * Copyright © 2010,2011,2013 Google, Inc.
4 *
5 * This is part of HarfBuzz, a text shaping library.
6 *
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.
12 *
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
17 * DAMAGE.
18 *
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.
24 *
25 * Red Hat Author(s): Behdad Esfahbod
26 * Google Author(s): Behdad Esfahbod
27 */
28
29 #include "hb.hh"
30
31 #ifndef HB_NO_AAT_SHAPE
32
33 #include "hb-aat-map.hh"
34
35 #include "hb-aat-layout.hh"
36 #include "hb-aat-layout-feat-table.hh"
37
38
add_feature(hb_tag_t tag,unsigned value)39 void hb_aat_map_builder_t::add_feature (hb_tag_t tag, unsigned value)
40 {
41 if (!face->table.feat->has_data ()) return;
42
43 if (tag == HB_TAG ('a','a','l','t'))
44 {
45 if (!face->table.feat->exposes_feature (HB_AAT_LAYOUT_FEATURE_TYPE_CHARACTER_ALTERNATIVES))
46 return;
47 feature_info_t *info = features.push();
48 info->type = HB_AAT_LAYOUT_FEATURE_TYPE_CHARACTER_ALTERNATIVES;
49 info->setting = (hb_aat_layout_feature_selector_t) value;
50 info->seq = features.length;
51 info->is_exclusive = true;
52 return;
53 }
54
55 const hb_aat_feature_mapping_t *mapping = hb_aat_layout_find_feature_mapping (tag);
56 if (!mapping) return;
57
58 const AAT::FeatureName* feature = &face->table.feat->get_feature (mapping->aatFeatureType);
59 if (!feature->has_data ())
60 {
61 /* Special case: Chain::compile_flags will fall back to the deprecated version of
62 * small-caps if necessary, so we need to check for that possibility.
63 * https://github.com/harfbuzz/harfbuzz/issues/2307 */
64 if (mapping->aatFeatureType == HB_AAT_LAYOUT_FEATURE_TYPE_LOWER_CASE &&
65 mapping->selectorToEnable == HB_AAT_LAYOUT_FEATURE_SELECTOR_LOWER_CASE_SMALL_CAPS)
66 {
67 feature = &face->table.feat->get_feature (HB_AAT_LAYOUT_FEATURE_TYPE_LETTER_CASE);
68 if (!feature->has_data ()) return;
69 }
70 else return;
71 }
72
73 feature_info_t *info = features.push();
74 info->type = mapping->aatFeatureType;
75 info->setting = value ? mapping->selectorToEnable : mapping->selectorToDisable;
76 info->seq = features.length;
77 info->is_exclusive = feature->is_exclusive ();
78 }
79
80 void
compile(hb_aat_map_t & m)81 hb_aat_map_builder_t::compile (hb_aat_map_t &m)
82 {
83 /* Sort features and merge duplicates */
84 if (features.length)
85 {
86 features.qsort ();
87 unsigned int j = 0;
88 for (unsigned int i = 1; i < features.length; i++)
89 if (features[i].type != features[j].type ||
90 /* Nonexclusive feature selectors come in even/odd pairs to turn a setting on/off
91 * respectively, so we mask out the low-order bit when checking for "duplicates"
92 * (selectors referring to the same feature setting) here. */
93 (!features[i].is_exclusive && ((features[i].setting & ~1) != (features[j].setting & ~1))))
94 features[++j] = features[i];
95 features.shrink (j + 1);
96 }
97
98 hb_aat_layout_compile_map (this, &m);
99 }
100
101
102 #endif
103