1 /*
2 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
3 *
4 * This code is free software; you can redistribute it and/or modify it
5 * under the terms of the GNU General Public License version 2 only, as
6 * published by the Free Software Foundation. Oracle designates this
7 * particular file as subject to the "Classpath" exception as provided
8 * by Oracle in the LICENSE file that accompanied this code.
9 *
10 * This code is distributed in the hope that it will be useful, but WITHOUT
11 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
12 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
13 * version 2 for more details (a copy is included in the LICENSE file that
14 * accompanied this code).
15 *
16 * You should have received a copy of the GNU General Public License version
17 * 2 along with this work; if not, write to the Free Software Foundation,
18 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
19 *
20 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
21 * or visit www.oracle.com if you need additional information or have any
22 * questions.
23 */
24
25 // This file is available under and governed by the GNU General Public
26 // License version 2 only, as published by the Free Software Foundation.
27 // However, the following notice accompanied the original version of this
28 // file:
29 //
30 /*
31 * Copyright © 2009,2010 Red Hat, Inc.
32 * Copyright © 2010,2011,2012,2013 Google, Inc.
33 *
34 * This is part of HarfBuzz, a text shaping library.
35 *
36 * Permission is hereby granted, without written agreement and without
37 * license or royalty fees, to use, copy, modify, and distribute this
38 * software and its documentation for any purpose, provided that the
39 * above copyright notice and the following two paragraphs appear in
40 * all copies of this software.
41 *
42 * IN NO EVENT SHALL THE COPYRIGHT HOLDER BE LIABLE TO ANY PARTY FOR
43 * DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES
44 * ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN
45 * IF THE COPYRIGHT HOLDER HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH
46 * DAMAGE.
47 *
48 * THE COPYRIGHT HOLDER SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING,
49 * BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
50 * FITNESS FOR A PARTICULAR PURPOSE. THE SOFTWARE PROVIDED HEREUNDER IS
51 * ON AN "AS IS" BASIS, AND THE COPYRIGHT HOLDER HAS NO OBLIGATION TO
52 * PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.
53 *
54 * Red Hat Author(s): Behdad Esfahbod
55 * Google Author(s): Behdad Esfahbod
56 */
57
58 #ifndef HB_OT_MAP_PRIVATE_HH
59 #define HB_OT_MAP_PRIVATE_HH
60
61 #include "hb-buffer-private.hh"
62
63
64 struct hb_ot_shape_plan_t;
65
66 static const hb_tag_t table_tags[2] = {HB_OT_TAG_GSUB, HB_OT_TAG_GPOS};
67
68 struct hb_ot_map_t
69 {
70 friend struct hb_ot_map_builder_t;
71
72 public:
73
74 struct feature_map_t {
75 hb_tag_t tag; /* should be first for our bsearch to work */
76 unsigned int index[2]; /* GSUB/GPOS */
77 unsigned int stage[2]; /* GSUB/GPOS */
78 unsigned int shift;
79 hb_mask_t mask;
80 hb_mask_t _1_mask; /* mask for value=1, for quick access */
81 unsigned int needs_fallback : 1;
82 unsigned int auto_zwj : 1;
83
84 static int cmp (const feature_map_t *a, const feature_map_t *b)
85 { return a->tag < b->tag ? -1 : a->tag > b->tag ? 1 : 0; }
86 };
87
88 struct lookup_map_t {
89 unsigned short index;
90 unsigned short auto_zwj : 1;
91 hb_mask_t mask;
92
93 static int cmp (const lookup_map_t *a, const lookup_map_t *b)
94 { return a->index < b->index ? -1 : a->index > b->index ? 1 : 0; }
95 };
96
97 typedef void (*pause_func_t) (const struct hb_ot_shape_plan_t *plan, hb_font_t *font, hb_buffer_t *buffer);
98
99 struct stage_map_t {
100 unsigned int last_lookup; /* Cumulative */
101 pause_func_t pause_func;
102 };
103
104
105 hb_ot_map_t (void) { memset (this, 0, sizeof (*this)); }
106
107 inline hb_mask_t get_global_mask (void) const { return global_mask; }
108
109 inline hb_mask_t get_mask (hb_tag_t feature_tag, unsigned int *shift = NULL) const {
110 const feature_map_t *map = features.bsearch (&feature_tag);
111 if (shift) *shift = map ? map->shift : 0;
112 return map ? map->mask : 0;
113 }
114
115 inline bool needs_fallback (hb_tag_t feature_tag) const {
116 const feature_map_t *map = features.bsearch (&feature_tag);
117 return map ? map->needs_fallback : false;
118 }
119
120 inline hb_mask_t get_1_mask (hb_tag_t feature_tag) const {
121 const feature_map_t *map = features.bsearch (&feature_tag);
122 return map ? map->_1_mask : 0;
123 }
124
125 inline unsigned int get_feature_index (unsigned int table_index, hb_tag_t feature_tag) const {
126 const feature_map_t *map = features.bsearch (&feature_tag);
127 return map ? map->index[table_index] : HB_OT_LAYOUT_NO_FEATURE_INDEX;
128 }
129
130 inline unsigned int get_feature_stage (unsigned int table_index, hb_tag_t feature_tag) const {
131 const feature_map_t *map = features.bsearch (&feature_tag);
132 return map ? map->stage[table_index] : (unsigned int) -1;
133 }
134
135 inline void get_stage_lookups (unsigned int table_index, unsigned int stage,
136 const struct lookup_map_t **plookups, unsigned int *lookup_count) const {
137 if (unlikely (stage == (unsigned int) -1)) {
138 *plookups = NULL;
139 *lookup_count = 0;
140 return;
141 }
142 assert (stage <= stages[table_index].len);
143 unsigned int start = stage ? stages[table_index][stage - 1].last_lookup : 0;
144 unsigned int end = stage < stages[table_index].len ? stages[table_index][stage].last_lookup : lookups[table_index].len;
145 *plookups = &lookups[table_index][start];
146 *lookup_count = end - start;
147 }
148
149 HB_INTERNAL void collect_lookups (unsigned int table_index, hb_set_t *lookups) const;
150 template <typename Proxy>
151 HB_INTERNAL inline void apply (const Proxy &proxy,
152 const struct hb_ot_shape_plan_t *plan, hb_font_t *font, hb_buffer_t *buffer) const;
153 HB_INTERNAL void substitute (const struct hb_ot_shape_plan_t *plan, hb_font_t *font, hb_buffer_t *buffer) const;
154 HB_INTERNAL void position (const struct hb_ot_shape_plan_t *plan, hb_font_t *font, hb_buffer_t *buffer) const;
155
156 inline void finish (void) {
157 features.finish ();
158 for (unsigned int table_index = 0; table_index < 2; table_index++)
159 {
160 lookups[table_index].finish ();
161 stages[table_index].finish ();
162 }
163 }
164
165 public:
166 hb_tag_t chosen_script[2];
167 bool found_script[2];
168
169 private:
170
171 HB_INTERNAL void add_lookups (hb_face_t *face,
172 unsigned int table_index,
173 unsigned int feature_index,
174 hb_mask_t mask,
175 bool auto_zwj);
176
177 hb_mask_t global_mask;
178
179 hb_prealloced_array_t<feature_map_t, 8> features;
180 hb_prealloced_array_t<lookup_map_t, 32> lookups[2]; /* GSUB/GPOS */
181 hb_prealloced_array_t<stage_map_t, 4> stages[2]; /* GSUB/GPOS */
182 };
183
184 enum hb_ot_map_feature_flags_t {
185 F_NONE = 0x0000u,
186 F_GLOBAL = 0x0001u, /* Feature applies to all characters; results in no mask allocated for it. */
187 F_HAS_FALLBACK = 0x0002u, /* Has fallback implementation, so include mask bit even if feature not found. */
188 F_MANUAL_ZWJ = 0x0004u, /* Don't skip over ZWJ when matching. */
189 F_GLOBAL_SEARCH = 0x0008u /* If feature not found in LangSys, look for it in global feature list and pick one. */
190 };
191 /* Macro version for where const is desired. */
192 #define F_COMBINE(l,r) (hb_ot_map_feature_flags_t ((unsigned int) (l) | (unsigned int) (r)))
193 static inline hb_ot_map_feature_flags_t
194 operator | (hb_ot_map_feature_flags_t l, hb_ot_map_feature_flags_t r)
195 { return hb_ot_map_feature_flags_t ((unsigned int) l | (unsigned int) r); }
196 static inline hb_ot_map_feature_flags_t
197 operator & (hb_ot_map_feature_flags_t l, hb_ot_map_feature_flags_t r)
198 { return hb_ot_map_feature_flags_t ((unsigned int) l & (unsigned int) r); }
199 static inline hb_ot_map_feature_flags_t
200 operator ~ (hb_ot_map_feature_flags_t r)
201 { return hb_ot_map_feature_flags_t (~(unsigned int) r); }
202 static inline hb_ot_map_feature_flags_t&
203 operator |= (hb_ot_map_feature_flags_t &l, hb_ot_map_feature_flags_t r)
204 { l = l | r; return l; }
205 static inline hb_ot_map_feature_flags_t&
206 operator &= (hb_ot_map_feature_flags_t& l, hb_ot_map_feature_flags_t r)
207 { l = l & r; return l; }
208
209
210 struct hb_ot_map_builder_t
211 {
212 public:
213
214 HB_INTERNAL hb_ot_map_builder_t (hb_face_t *face_,
215 const hb_segment_properties_t *props_);
216
217 HB_INTERNAL void add_feature (hb_tag_t tag, unsigned int value,
218 hb_ot_map_feature_flags_t flags);
219
220 inline void add_global_bool_feature (hb_tag_t tag)
221 { add_feature (tag, 1, F_GLOBAL); }
222
223 inline void add_gsub_pause (hb_ot_map_t::pause_func_t pause_func)
224 { add_pause (0, pause_func); }
225 inline void add_gpos_pause (hb_ot_map_t::pause_func_t pause_func)
226 { add_pause (1, pause_func); }
227
228 HB_INTERNAL void compile (struct hb_ot_map_t &m);
229
230 inline void finish (void) {
231 feature_infos.finish ();
232 for (unsigned int table_index = 0; table_index < 2; table_index++)
233 {
234 stages[table_index].finish ();
235 }
236 }
237
238 private:
239
240 struct feature_info_t {
241 hb_tag_t tag;
242 unsigned int seq; /* sequence#, used for stable sorting only */
243 unsigned int max_value;
244 hb_ot_map_feature_flags_t flags;
245 unsigned int default_value; /* for non-global features, what should the unset glyphs take */
246 unsigned int stage[2]; /* GSUB/GPOS */
247
248 static int cmp (const feature_info_t *a, const feature_info_t *b)
249 { return (a->tag != b->tag) ? (a->tag < b->tag ? -1 : 1) : (a->seq < b->seq ? -1 : 1); }
250 };
251
252 struct stage_info_t {
253 unsigned int index;
254 hb_ot_map_t::pause_func_t pause_func;
255 };
256
257 HB_INTERNAL void add_pause (unsigned int table_index, hb_ot_map_t::pause_func_t pause_func);
258
259 public:
260
261 hb_face_t *face;
262 hb_segment_properties_t props;
263
264 hb_tag_t chosen_script[2];
265 bool found_script[2];
266 unsigned int script_index[2], language_index[2];
267
268 private:
269
270 unsigned int current_stage[2]; /* GSUB/GPOS */
271 hb_prealloced_array_t<feature_info_t, 32> feature_infos;
272 hb_prealloced_array_t<stage_info_t, 8> stages[2]; /* GSUB/GPOS */
273 };
274
275
276
277 #endif /* HB_OT_MAP_PRIVATE_HH */