1 /*
2 * Copyright © 2011 Google, Inc.
3 *
4 * This is part of HarfBuzz, a text shaping 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 * Google Author(s): Behdad Esfahbod
25 */
26
27 #include "hb-shaper-impl.hh"
28
29
30 /*
31 * shaper face data
32 */
33
34 struct hb_fallback_face_data_t {};
35
36 hb_fallback_face_data_t *
_hb_fallback_shaper_face_data_create(hb_face_t * face HB_UNUSED)37 _hb_fallback_shaper_face_data_create (hb_face_t *face HB_UNUSED)
38 {
39 return (hb_fallback_face_data_t *) HB_SHAPER_DATA_SUCCEEDED;
40 }
41
42 void
_hb_fallback_shaper_face_data_destroy(hb_fallback_face_data_t * data HB_UNUSED)43 _hb_fallback_shaper_face_data_destroy (hb_fallback_face_data_t *data HB_UNUSED)
44 {
45 }
46
47
48 /*
49 * shaper font data
50 */
51
52 struct hb_fallback_font_data_t {};
53
54 hb_fallback_font_data_t *
_hb_fallback_shaper_font_data_create(hb_font_t * font HB_UNUSED)55 _hb_fallback_shaper_font_data_create (hb_font_t *font HB_UNUSED)
56 {
57 return (hb_fallback_font_data_t *) HB_SHAPER_DATA_SUCCEEDED;
58 }
59
60 void
_hb_fallback_shaper_font_data_destroy(hb_fallback_font_data_t * data HB_UNUSED)61 _hb_fallback_shaper_font_data_destroy (hb_fallback_font_data_t *data HB_UNUSED)
62 {
63 }
64
65
66 /*
67 * shaper
68 */
69
70 hb_bool_t
_hb_fallback_shape(hb_shape_plan_t * shape_plan HB_UNUSED,hb_font_t * font,hb_buffer_t * buffer,const hb_feature_t * features HB_UNUSED,unsigned int num_features HB_UNUSED)71 _hb_fallback_shape (hb_shape_plan_t *shape_plan HB_UNUSED,
72 hb_font_t *font,
73 hb_buffer_t *buffer,
74 const hb_feature_t *features HB_UNUSED,
75 unsigned int num_features HB_UNUSED)
76 {
77 /* TODO
78 *
79 * - Apply fallback kern.
80 * - Handle Variation Selectors?
81 * - Apply normalization?
82 *
83 * This will make the fallback shaper into a dumb "TrueType"
84 * shaper which many people unfortunately still request.
85 */
86
87 hb_codepoint_t space;
88 bool has_space = (bool) font->get_nominal_glyph (' ', &space);
89
90 buffer->clear_positions ();
91
92 hb_direction_t direction = buffer->props.direction;
93 hb_unicode_funcs_t *unicode = buffer->unicode;
94 unsigned int count = buffer->len;
95 hb_glyph_info_t *info = buffer->info;
96 hb_glyph_position_t *pos = buffer->pos;
97 for (unsigned int i = 0; i < count; i++)
98 {
99 if (has_space && unicode->is_default_ignorable (info[i].codepoint)) {
100 info[i].codepoint = space;
101 pos[i].x_advance = 0;
102 pos[i].y_advance = 0;
103 continue;
104 }
105 (void) font->get_nominal_glyph (info[i].codepoint, &info[i].codepoint);
106 font->get_glyph_advance_for_direction (info[i].codepoint,
107 direction,
108 &pos[i].x_advance,
109 &pos[i].y_advance);
110 font->subtract_glyph_origin_for_direction (info[i].codepoint,
111 direction,
112 &pos[i].x_offset,
113 &pos[i].y_offset);
114 }
115
116 if (HB_DIRECTION_IS_BACKWARD (direction))
117 hb_buffer_reverse (buffer);
118
119 buffer->safe_to_break_all ();
120
121 return true;
122 }
123