hb-ot-layout.h revision 2014b8d110231b13e524008282ece7451f1ae9e7 
1/*
2 * Copyright (C) 2007,2008,2009  Red Hat, Inc.
3 *
4 *  This is part of HarfBuzz, an OpenType Layout engine library.
5 *
6 * Permission is hereby granted, without written agreement and without
7 * license or royalty fees, to use, copy, modify, and distribute this
8 * software and its documentation for any purpose, provided that the
9 * above copyright notice and the following two paragraphs appear in
10 * all copies of this software.
11 *
12 * IN NO EVENT SHALL THE COPYRIGHT HOLDER BE LIABLE TO ANY PARTY FOR
13 * DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES
14 * ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN
15 * IF THE COPYRIGHT HOLDER HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH
16 * DAMAGE.
17 *
18 * THE COPYRIGHT HOLDER SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING,
19 * BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
20 * FITNESS FOR A PARTICULAR PURPOSE.  THE SOFTWARE PROVIDED HEREUNDER IS
21 * ON AN "AS IS" BASIS, AND THE COPYRIGHT HOLDER HAS NO OBLIGATION TO
22 * PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.
23 *
24 * Red Hat Author(s): Behdad Esfahbod
25 */
26
27#ifndef HB_OT_LAYOUT_H
28#define HB_OT_LAYOUT_H
29
30#include "hb-common.h"
31#include "hb-buffer.h"
32#include "hb-font.h"
33
34#include "hb-ot-tag.h"
35
36HB_BEGIN_DECLS
37
38#define HB_OT_TAG_GDEF HB_TAG('G','D','E','F')
39#define HB_OT_TAG_GSUB HB_TAG('G','S','U','B')
40#define HB_OT_TAG_GPOS HB_TAG('G','P','O','S')
41
42/*
43 * GDEF
44 */
45
46typedef enum {
47  HB_OT_LAYOUT_GLYPH_CLASS_UNCLASSIFIED	= 0x0000,
48  HB_OT_LAYOUT_GLYPH_CLASS_BASE_GLYPH	= 0x0002,
49  HB_OT_LAYOUT_GLYPH_CLASS_LIGATURE	= 0x0004,
50  HB_OT_LAYOUT_GLYPH_CLASS_MARK		= 0x0008,
51  HB_OT_LAYOUT_GLYPH_CLASS_COMPONENT	= 0x0010
52} hb_ot_layout_glyph_class_t;
53
54/* XXX These should eventually be removed as we move synthesized glyph
55 * classes in harfbuzz. */
56
57hb_bool_t
58hb_ot_layout_has_glyph_classes (hb_face_t *face);
59
60hb_ot_layout_glyph_class_t
61hb_ot_layout_get_glyph_class (hb_face_t      *face,
62			      hb_codepoint_t  glyph);
63
64void
65hb_ot_layout_set_glyph_class (hb_face_t                 *face,
66			      hb_codepoint_t             glyph,
67			      hb_ot_layout_glyph_class_t klass);
68
69void
70hb_ot_layout_build_glyph_classes (hb_face_t      *face,
71				  uint16_t        num_total_glyphs,
72				  hb_codepoint_t *glyphs,
73				  unsigned char  *klasses,
74				  uint16_t        count);
75
76/* Not that useful.  Provides list of attach points for a glyph that a
77 * client may want to cache */
78unsigned int
79hb_ot_layout_get_attach_points (hb_face_t      *face,
80				hb_codepoint_t  glyph,
81				unsigned int    start_offset,
82				unsigned int   *point_count /* IN/OUT */,
83				unsigned int   *point_array /* OUT */);
84
85/* Ligature caret positions */
86unsigned int
87hb_ot_layout_get_lig_carets (hb_font_t      *font,
88			     hb_face_t      *face,
89			     hb_codepoint_t  glyph,
90			     unsigned int    start_offset,
91			     unsigned int   *caret_count /* IN/OUT */,
92			     int            *caret_array /* OUT */);
93
94
95/*
96 * GSUB/GPOS feature query and enumeration interface
97 */
98
99#define HB_OT_LAYOUT_NO_SCRIPT_INDEX		((unsigned int) 0xFFFF)
100#define HB_OT_LAYOUT_NO_FEATURE_INDEX		((unsigned int) 0xFFFF)
101#define HB_OT_LAYOUT_DEFAULT_LANGUAGE_INDEX	((unsigned int) 0xFFFF)
102
103unsigned int
104hb_ot_layout_table_get_script_tags (hb_face_t    *face,
105				    hb_tag_t      table_tag,
106				    unsigned int  start_offset,
107				    unsigned int *script_count /* IN/OUT */,
108				    hb_tag_t     *script_tags /* OUT */);
109
110hb_bool_t
111hb_ot_layout_table_find_script (hb_face_t    *face,
112				hb_tag_t      table_tag,
113				hb_tag_t      script_tag,
114				unsigned int *script_index);
115
116/* Like find_script, but takes zero-terminated array of scripts to test */
117hb_bool_t
118hb_ot_layout_table_choose_script (hb_face_t      *face,
119				  hb_tag_t        table_tag,
120				  const hb_tag_t *script_tags,
121				  unsigned int   *script_index);
122
123unsigned int
124hb_ot_layout_table_get_feature_tags (hb_face_t    *face,
125				     hb_tag_t      table_tag,
126				     unsigned int  start_offset,
127				     unsigned int *feature_count /* IN/OUT */,
128				     hb_tag_t     *feature_tags /* OUT */);
129
130unsigned int
131hb_ot_layout_script_get_language_tags (hb_face_t    *face,
132				       hb_tag_t      table_tag,
133				       unsigned int  script_index,
134				       unsigned int  start_offset,
135				       unsigned int *language_count /* IN/OUT */,
136				       hb_tag_t     *language_tags /* OUT */);
137
138hb_bool_t
139hb_ot_layout_script_find_language (hb_face_t    *face,
140				   hb_tag_t      table_tag,
141				   unsigned int  script_index,
142				   hb_tag_t      language_tag,
143				   unsigned int *language_index);
144
145hb_bool_t
146hb_ot_layout_language_get_required_feature_index (hb_face_t    *face,
147						  hb_tag_t      table_tag,
148						  unsigned int  script_index,
149						  unsigned int  language_index,
150						  unsigned int *feature_index);
151
152unsigned int
153hb_ot_layout_language_get_feature_indexes (hb_face_t    *face,
154					   hb_tag_t      table_tag,
155					   unsigned int  script_index,
156					   unsigned int  language_index,
157					   unsigned int  start_offset,
158					   unsigned int *feature_count /* IN/OUT */,
159					   unsigned int *feature_indexes /* OUT */);
160
161unsigned int
162hb_ot_layout_language_get_feature_tags (hb_face_t    *face,
163					hb_tag_t      table_tag,
164					unsigned int  script_index,
165					unsigned int  language_index,
166					unsigned int  start_offset,
167					unsigned int *feature_count /* IN/OUT */,
168					hb_tag_t     *feature_tags /* OUT */);
169
170hb_bool_t
171hb_ot_layout_language_find_feature (hb_face_t    *face,
172				    hb_tag_t      table_tag,
173				    unsigned int  script_index,
174				    unsigned int  language_index,
175				    hb_tag_t      feature_tag,
176				    unsigned int *feature_index);
177
178unsigned int
179hb_ot_layout_feature_get_lookup_indexes (hb_face_t    *face,
180					 hb_tag_t      table_tag,
181					 unsigned int  feature_index,
182					 unsigned int  start_offset,
183					 unsigned int *lookup_count /* IN/OUT */,
184					 unsigned int *lookup_indexes /* OUT */);
185
186
187/*
188 * GSUB
189 */
190
191hb_bool_t
192hb_ot_layout_has_substitution (hb_face_t *face);
193
194hb_bool_t
195hb_ot_layout_substitute_lookup (hb_face_t    *face,
196				hb_buffer_t  *buffer,
197				unsigned int  lookup_index,
198				hb_mask_t     mask);
199
200/*
201 * GPOS
202 */
203
204hb_bool_t
205hb_ot_layout_has_positioning (hb_face_t *face);
206
207hb_bool_t
208hb_ot_layout_position_lookup (hb_font_t    *font,
209			      hb_face_t    *face,
210			      hb_buffer_t  *buffer,
211			      unsigned int  lookup_index,
212			      hb_mask_t     mask);
213
214/* Should be called after all the position_lookup's are done */
215void
216hb_ot_layout_position_finish (hb_font_t    *font,
217			      hb_face_t    *face,
218			      hb_buffer_t  *buffer);
219
220
221HB_END_DECLS
222
223#endif /* HB_OT_LAYOUT_H */
224