1 | /* |
2 | * Copyright © 2015 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 | #ifndef HB_OT_GLYF_TABLE_HH |
28 | #define HB_OT_GLYF_TABLE_HH |
29 | |
30 | #include "hb-open-type-private.hh" |
31 | #include "hb-ot-head-table.hh" |
32 | |
33 | |
34 | namespace OT { |
35 | |
36 | |
37 | /* |
38 | * loca -- Index to Location |
39 | */ |
40 | |
41 | #define HB_OT_TAG_loca HB_TAG('l','o','c','a') |
42 | |
43 | |
44 | struct loca |
45 | { |
46 | friend struct glyf; |
47 | |
48 | static const hb_tag_t tableTag = HB_OT_TAG_loca; |
49 | |
50 | inline bool sanitize (hb_sanitize_context_t *c) const |
51 | { |
52 | TRACE_SANITIZE (this); |
53 | return_trace (true); |
54 | } |
55 | |
56 | protected: |
57 | UINT8 dataX[VAR]; /* Location data. */ |
58 | DEFINE_SIZE_ARRAY (0, dataX); |
59 | }; |
60 | |
61 | |
62 | /* |
63 | * glyf -- TrueType Glyph Data |
64 | */ |
65 | |
66 | #define HB_OT_TAG_glyf HB_TAG('g','l','y','f') |
67 | |
68 | |
69 | struct glyf |
70 | { |
71 | static const hb_tag_t tableTag = HB_OT_TAG_glyf; |
72 | |
73 | inline bool sanitize (hb_sanitize_context_t *c) const |
74 | { |
75 | TRACE_SANITIZE (this); |
76 | /* We don't check for anything specific here. The users of the |
77 | * struct do all the hard work... */ |
78 | return_trace (true); |
79 | } |
80 | |
81 | struct |
82 | { |
83 | INT16 ; /* If the number of contours is |
84 | * greater than or equal to zero, |
85 | * this is a simple glyph; if negative, |
86 | * this is a composite glyph. */ |
87 | FWORD ; /* Minimum x for coordinate data. */ |
88 | FWORD ; /* Minimum y for coordinate data. */ |
89 | FWORD ; /* Maximum x for coordinate data. */ |
90 | FWORD ; /* Maximum y for coordinate data. */ |
91 | |
92 | DEFINE_SIZE_STATIC (10); |
93 | }; |
94 | |
95 | struct accelerator_t |
96 | { |
97 | inline void init (hb_face_t *face) |
98 | { |
99 | hb_blob_t *head_blob = Sanitizer<head>::sanitize (blob: face->reference_table (HB_OT_TAG_head)); |
100 | const head *head_table = Sanitizer<head>::lock_instance (blob: head_blob); |
101 | if ((unsigned int) head_table->indexToLocFormat > 1 || head_table->glyphDataFormat != 0) |
102 | { |
103 | /* Unknown format. Leave num_glyphs=0, that takes care of disabling us. */ |
104 | hb_blob_destroy (blob: head_blob); |
105 | return; |
106 | } |
107 | short_offset = 0 == head_table->indexToLocFormat; |
108 | hb_blob_destroy (blob: head_blob); |
109 | |
110 | loca_blob = Sanitizer<loca>::sanitize (blob: face->reference_table (HB_OT_TAG_loca)); |
111 | loca_table = Sanitizer<loca>::lock_instance (blob: loca_blob); |
112 | glyf_blob = Sanitizer<glyf>::sanitize (blob: face->reference_table (HB_OT_TAG_glyf)); |
113 | glyf_table = Sanitizer<glyf>::lock_instance (blob: glyf_blob); |
114 | |
115 | num_glyphs = MAX (a: 1u, b: hb_blob_get_length (blob: loca_blob) / (short_offset ? 2 : 4)) - 1; |
116 | glyf_len = hb_blob_get_length (blob: glyf_blob); |
117 | } |
118 | |
119 | inline void fini (void) |
120 | { |
121 | hb_blob_destroy (blob: loca_blob); |
122 | hb_blob_destroy (blob: glyf_blob); |
123 | } |
124 | |
125 | inline bool get_extents (hb_codepoint_t glyph, |
126 | hb_glyph_extents_t *extents) const |
127 | { |
128 | if (unlikely (glyph >= num_glyphs)) |
129 | return false; |
130 | |
131 | unsigned int start_offset, end_offset; |
132 | if (short_offset) |
133 | { |
134 | const UINT16 *offsets = (const UINT16 *) loca_table->dataX; |
135 | start_offset = 2 * offsets[glyph]; |
136 | end_offset = 2 * offsets[glyph + 1]; |
137 | } |
138 | else |
139 | { |
140 | const UINT32 *offsets = (const UINT32 *) loca_table->dataX; |
141 | start_offset = offsets[glyph]; |
142 | end_offset = offsets[glyph + 1]; |
143 | } |
144 | |
145 | if (start_offset > end_offset || end_offset > glyf_len) |
146 | return false; |
147 | |
148 | if (end_offset - start_offset < GlyphHeader::static_size) |
149 | return true; /* Empty glyph; zero extents. */ |
150 | |
151 | const GlyphHeader & = StructAtOffset<GlyphHeader> (P: glyf_table, offset: start_offset); |
152 | |
153 | extents->x_bearing = MIN (a: glyph_header.xMin, b: glyph_header.xMax); |
154 | extents->y_bearing = MAX (a: glyph_header.yMin, b: glyph_header.yMax); |
155 | extents->width = MAX (a: glyph_header.xMin, b: glyph_header.xMax) - extents->x_bearing; |
156 | extents->height = MIN (a: glyph_header.yMin, b: glyph_header.yMax) - extents->y_bearing; |
157 | |
158 | return true; |
159 | } |
160 | |
161 | private: |
162 | bool short_offset; |
163 | unsigned int num_glyphs; |
164 | const loca *loca_table; |
165 | const glyf *glyf_table; |
166 | hb_blob_t *loca_blob; |
167 | hb_blob_t *glyf_blob; |
168 | unsigned int glyf_len; |
169 | }; |
170 | |
171 | protected: |
172 | UINT8 dataX[VAR]; /* Glyphs data. */ |
173 | |
174 | DEFINE_SIZE_ARRAY (0, dataX); |
175 | }; |
176 | |
177 | } /* namespace OT */ |
178 | |
179 | |
180 | #endif /* HB_OT_GLYF_TABLE_HH */ |
181 | |