2 * Copyright © 2009,2010 Red Hat, Inc.
3 * Copyright © 2010,2011,2012,2013 Google, Inc.
5 * This is part of HarfBuzz, a text shaping library.
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.
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
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.
25 * Red Hat Author(s): Behdad Esfahbod
26 * Google Author(s): Behdad Esfahbod
32 #include "hb-buffer.hh"
35 #define HB_OT_MAP_MAX_BITS 8u
36 #define HB_OT_MAP_MAX_VALUE ((1u << HB_OT_MAP_MAX_BITS) - 1u)
38 struct hb_ot_shape_plan_t;
40 static const hb_tag_t table_tags[2] = {HB_OT_TAG_GSUB, HB_OT_TAG_GPOS};
44 friend struct hb_ot_map_builder_t;
48 struct feature_map_t {
49 hb_tag_t tag; /* should be first for our bsearch to work */
50 unsigned int index[2]; /* GSUB/GPOS */
51 unsigned int stage[2]; /* GSUB/GPOS */
54 hb_mask_t _1_mask; /* mask for value=1, for quick access */
55 unsigned int needs_fallback : 1;
56 unsigned int auto_zwnj : 1;
57 unsigned int auto_zwj : 1;
58 unsigned int random : 1;
60 int cmp (const hb_tag_t tag_) const
61 { return tag_ < tag ? -1 : tag_ > tag ? 1 : 0; }
66 unsigned short auto_zwnj : 1;
67 unsigned short auto_zwj : 1;
68 unsigned short random : 1;
71 HB_INTERNAL static int cmp (const void *pa, const void *pb)
73 const lookup_map_t *a = (const lookup_map_t *) pa;
74 const lookup_map_t *b = (const lookup_map_t *) pb;
75 return a->index < b->index ? -1 : a->index > b->index ? 1 : 0;
79 typedef void (*pause_func_t) (const struct hb_ot_shape_plan_t *plan, hb_font_t *font, hb_buffer_t *buffer);
82 unsigned int last_lookup; /* Cumulative */
83 pause_func_t pause_func;
88 memset (this, 0, sizeof (*this));
91 for (unsigned int table_index = 0; table_index < 2; table_index++)
93 lookups[table_index].init ();
94 stages[table_index].init ();
100 for (unsigned int table_index = 0; table_index < 2; table_index++)
102 lookups[table_index].fini ();
103 stages[table_index].fini ();
107 hb_mask_t get_global_mask () const { return global_mask; }
109 hb_mask_t get_mask (hb_tag_t feature_tag, unsigned int *shift = nullptr) const
111 const feature_map_t *map = features.bsearch (feature_tag);
112 if (shift) *shift = map ? map->shift : 0;
113 return map ? map->mask : 0;
116 bool needs_fallback (hb_tag_t feature_tag) const
118 const feature_map_t *map = features.bsearch (feature_tag);
119 return map ? map->needs_fallback : false;
122 hb_mask_t get_1_mask (hb_tag_t feature_tag) const
124 const feature_map_t *map = features.bsearch (feature_tag);
125 return map ? map->_1_mask : 0;
128 unsigned int get_feature_index (unsigned int table_index, hb_tag_t feature_tag) const
130 const feature_map_t *map = features.bsearch (feature_tag);
131 return map ? map->index[table_index] : HB_OT_LAYOUT_NO_FEATURE_INDEX;
134 unsigned int get_feature_stage (unsigned int table_index, hb_tag_t feature_tag) const
136 const feature_map_t *map = features.bsearch (feature_tag);
137 return map ? map->stage[table_index] : UINT_MAX;
140 void get_stage_lookups (unsigned int table_index, unsigned int stage,
141 const struct lookup_map_t **plookups, unsigned int *lookup_count) const
143 if (unlikely (stage > stages[table_index].length))
149 unsigned int start = stage ? stages[table_index][stage - 1].last_lookup : 0;
150 unsigned int end = stage < stages[table_index].length ? stages[table_index][stage].last_lookup : lookups[table_index].length;
151 *plookups = end == start ? nullptr : &lookups[table_index][start];
152 *lookup_count = end - start;
155 HB_INTERNAL void collect_lookups (unsigned int table_index, hb_set_t *lookups) const;
156 template <typename Proxy>
157 HB_INTERNAL void apply (const Proxy &proxy,
158 const struct hb_ot_shape_plan_t *plan, hb_font_t *font, hb_buffer_t *buffer) const;
159 HB_INTERNAL void substitute (const struct hb_ot_shape_plan_t *plan, hb_font_t *font, hb_buffer_t *buffer) const;
160 HB_INTERNAL void position (const struct hb_ot_shape_plan_t *plan, hb_font_t *font, hb_buffer_t *buffer) const;
163 hb_tag_t chosen_script[2];
164 bool found_script[2];
168 hb_mask_t global_mask;
170 hb_sorted_vector_t<feature_map_t> features;
171 hb_vector_t<lookup_map_t> lookups[2]; /* GSUB/GPOS */
172 hb_vector_t<stage_map_t> stages[2]; /* GSUB/GPOS */
175 enum hb_ot_map_feature_flags_t
178 F_GLOBAL = 0x0001u, /* Feature applies to all characters; results in no mask allocated for it. */
179 F_HAS_FALLBACK = 0x0002u, /* Has fallback implementation, so include mask bit even if feature not found. */
180 F_MANUAL_ZWNJ = 0x0004u, /* Don't skip over ZWNJ when matching **context**. */
181 F_MANUAL_ZWJ = 0x0008u, /* Don't skip over ZWJ when matching **input**. */
182 F_MANUAL_JOINERS = F_MANUAL_ZWNJ | F_MANUAL_ZWJ,
183 F_GLOBAL_MANUAL_JOINERS= F_GLOBAL | F_MANUAL_JOINERS,
184 F_GLOBAL_HAS_FALLBACK = F_GLOBAL | F_HAS_FALLBACK,
185 F_GLOBAL_SEARCH = 0x0010u, /* If feature not found in LangSys, look for it in global feature list and pick one. */
186 F_RANDOM = 0x0020u /* Randomly select a glyph from an AlternateSubstFormat1 subtable. */
188 HB_MARK_AS_FLAG_T (hb_ot_map_feature_flags_t);
191 struct hb_ot_map_feature_t
194 hb_ot_map_feature_flags_t flags;
197 struct hb_ot_shape_plan_key_t;
199 struct hb_ot_map_builder_t
203 HB_INTERNAL hb_ot_map_builder_t (hb_face_t *face_,
204 const hb_segment_properties_t *props_);
206 HB_INTERNAL ~hb_ot_map_builder_t ();
208 HB_INTERNAL void add_feature (hb_tag_t tag,
209 hb_ot_map_feature_flags_t flags=F_NONE,
210 unsigned int value=1);
212 void add_feature (const hb_ot_map_feature_t &feat)
213 { add_feature (feat.tag, feat.flags); }
215 void enable_feature (hb_tag_t tag,
216 hb_ot_map_feature_flags_t flags=F_NONE,
217 unsigned int value=1)
218 { add_feature (tag, F_GLOBAL | flags, value); }
220 void disable_feature (hb_tag_t tag)
221 { add_feature (tag, F_GLOBAL, 0); }
223 void add_gsub_pause (hb_ot_map_t::pause_func_t pause_func)
224 { add_pause (0, pause_func); }
225 void add_gpos_pause (hb_ot_map_t::pause_func_t pause_func)
226 { add_pause (1, pause_func); }
228 HB_INTERNAL void compile (hb_ot_map_t &m,
229 const hb_ot_shape_plan_key_t &key);
233 HB_INTERNAL void add_lookups (hb_ot_map_t &m,
234 unsigned int table_index,
235 unsigned int feature_index,
236 unsigned int variations_index,
238 bool auto_zwnj = true,
239 bool auto_zwj = true,
240 bool random = false);
242 struct feature_info_t {
244 unsigned int seq; /* sequence#, used for stable sorting only */
245 unsigned int max_value;
246 hb_ot_map_feature_flags_t flags;
247 unsigned int default_value; /* for non-global features, what should the unset glyphs take */
248 unsigned int stage[2]; /* GSUB/GPOS */
250 HB_INTERNAL static int cmp (const void *pa, const void *pb)
252 const feature_info_t *a = (const feature_info_t *) pa;
253 const feature_info_t *b = (const feature_info_t *) pb;
254 return (a->tag != b->tag) ? (a->tag < b->tag ? -1 : 1) :
255 (a->seq < b->seq ? -1 : a->seq > b->seq ? 1 : 0);
259 struct stage_info_t {
261 hb_ot_map_t::pause_func_t pause_func;
264 HB_INTERNAL void add_pause (unsigned int table_index, hb_ot_map_t::pause_func_t pause_func);
269 hb_segment_properties_t props;
271 hb_tag_t chosen_script[2];
272 bool found_script[2];
273 unsigned int script_index[2], language_index[2];
277 unsigned int current_stage[2]; /* GSUB/GPOS */
278 hb_vector_t<feature_info_t> feature_infos;
279 hb_vector_t<stage_info_t> stages[2]; /* GSUB/GPOS */
284 #endif /* HB_OT_MAP_HH */