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 * |
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 |
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 * |
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 |
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 |
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 | |