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 © 2011 Google, Inc.
32 *
33 * This is part of HarfBuzz, a text shaping library.
34 *
35 * Permission is hereby granted, without written agreement and without
36 * license or royalty fees, to use, copy, modify, and distribute this
37 * software and its documentation for any purpose, provided that the
38 * above copyright notice and the following two paragraphs appear in
39 * all copies of this software.
40 *
41 * IN NO EVENT SHALL THE COPYRIGHT HOLDER BE LIABLE TO ANY PARTY FOR
42 * DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES
43 * ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN
44 * IF THE COPYRIGHT HOLDER HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH
45 * DAMAGE.
46 *
47 * THE COPYRIGHT HOLDER SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING,
48 * BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
49 * FITNESS FOR A PARTICULAR PURPOSE. THE SOFTWARE PROVIDED HEREUNDER IS
50 * ON AN "AS IS" BASIS, AND THE COPYRIGHT HOLDER HAS NO OBLIGATION TO
51 * PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.
52 *
53 * Google Author(s): Behdad Esfahbod
54 */
55
56 #define HB_SHAPER fallback
57 #include "hb-shaper-impl-private.hh"
58
59
60 /*
61 * shaper face data
62 */
63
64 struct hb_fallback_shaper_face_data_t {};
65
66 hb_fallback_shaper_face_data_t *
67 _hb_fallback_shaper_face_data_create (hb_face_t *face HB_UNUSED)
68 {
69 return (hb_fallback_shaper_face_data_t *) HB_SHAPER_DATA_SUCCEEDED;
70 }
71
72 void
73 _hb_fallback_shaper_face_data_destroy (hb_fallback_shaper_face_data_t *data HB_UNUSED)
74 {
75 }
76
77
78 /*
79 * shaper font data
80 */
81
82 struct hb_fallback_shaper_font_data_t {};
83
84 hb_fallback_shaper_font_data_t *
85 _hb_fallback_shaper_font_data_create (hb_font_t *font HB_UNUSED)
86 {
87 return (hb_fallback_shaper_font_data_t *) HB_SHAPER_DATA_SUCCEEDED;
88 }
89
90 void
91 _hb_fallback_shaper_font_data_destroy (hb_fallback_shaper_font_data_t *data HB_UNUSED)
92 {
93 }
94
95
96 /*
97 * shaper shape_plan data
98 */
99
100 struct hb_fallback_shaper_shape_plan_data_t {};
101
102 hb_fallback_shaper_shape_plan_data_t *
103 _hb_fallback_shaper_shape_plan_data_create (hb_shape_plan_t *shape_plan HB_UNUSED,
104 const hb_feature_t *user_features HB_UNUSED,
105 unsigned int num_user_features HB_UNUSED)
106 {
107 return (hb_fallback_shaper_shape_plan_data_t *) HB_SHAPER_DATA_SUCCEEDED;
108 }
109
110 void
111 _hb_fallback_shaper_shape_plan_data_destroy (hb_fallback_shaper_shape_plan_data_t *data HB_UNUSED)
112 {
113 }
114
115
116 /*
117 * shaper
118 */
119
120 hb_bool_t
121 _hb_fallback_shape (hb_shape_plan_t *shape_plan HB_UNUSED,
122 hb_font_t *font,
123 hb_buffer_t *buffer,
124 const hb_feature_t *features HB_UNUSED,
125 unsigned int num_features HB_UNUSED)
126 {
127 /* TODO
128 *
129 * - Apply fallback kern.
130 * - Handle Variation Selectors?
131 * - Apply normalization?
132 *
133 * This will make the fallback shaper into a dumb "TrueType"
134 * shaper which many people unfortunately still request.
135 */
136
137 hb_codepoint_t space;
138 bool has_space = font->get_glyph (' ', 0, &space);
139
140 buffer->clear_positions ();
141
142 hb_direction_t direction = buffer->props.direction;
143 hb_unicode_funcs_t *unicode = buffer->unicode;
144 unsigned int count = buffer->len;
145 hb_glyph_info_t *info = buffer->info;
146 hb_glyph_position_t *pos = buffer->pos;
147 for (unsigned int i = 0; i < count; i++)
148 {
149 if (has_space && unicode->is_default_ignorable (info[i].codepoint)) {
150 info[i].codepoint = space;
151 pos[i].x_advance = 0;
152 pos[i].y_advance = 0;
153 continue;
154 }
155 font->get_glyph (info[i].codepoint, 0, &info[i].codepoint);
156 font->get_glyph_advance_for_direction (info[i].codepoint,
157 direction,
158 &pos[i].x_advance,
159 &pos[i].y_advance);
160 font->subtract_glyph_origin_for_direction (info[i].codepoint,
161 direction,
162 &pos[i].x_offset,
163 &pos[i].y_offset);
164 }
165
166 if (HB_DIRECTION_IS_BACKWARD (direction))
167 hb_buffer_reverse (buffer);
168
169 return true;
170 }