1 /*
2 * Copyright © 2016 Google, Inc.
3 * Copyright © 2018 Ebrahim Byagowi
4 *
5 * This is part of HarfBuzz, a text shaping library.
6 *
7 * Permission is hereby granted, without written agreement and without
8 * license or royalty fees, to use, copy, modify, and distribute this
9 * software and its documentation for any purpose, provided that the
10 * above copyright notice and the following two paragraphs appear in
11 * all copies of this software.
12 *
13 * IN NO EVENT SHALL THE COPYRIGHT HOLDER BE LIABLE TO ANY PARTY FOR
14 * DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES
15 * ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN
16 * IF THE COPYRIGHT HOLDER HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH
17 * DAMAGE.
18 *
19 * THE COPYRIGHT HOLDER SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING,
20 * BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
21 * FITNESS FOR A PARTICULAR PURPOSE. THE SOFTWARE PROVIDED HEREUNDER IS
22 * ON AN "AS IS" BASIS, AND THE COPYRIGHT HOLDER HAS NO OBLIGATION TO
23 * PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.
24 *
25 * Google Author(s): Sascha Brawer
26 */
27
28 #ifndef HB_OT_COLOR_CPAL_TABLE_HH
29 #define HB_OT_COLOR_CPAL_TABLE_HH
30
31 #include "hb-open-type.hh"
32 #include "hb-ot-color.h"
33 #include "hb-ot-name.h"
34
35
36 /*
37 * CPAL -- Color Palette
38 * https://docs.microsoft.com/en-us/typography/opentype/spec/cpal
39 */
40 #define HB_OT_TAG_CPAL HB_TAG('C','P','A','L')
41
42
43 namespace OT {
44
45
46 struct CPALV1Tail
47 {
48 friend struct CPAL;
49
50 private:
51 hb_ot_color_palette_flags_t get_palette_flags (const void *base,
52 unsigned int palette_index,
53 unsigned int palette_count) const
54 {
55 if (!paletteFlagsZ) return HB_OT_COLOR_PALETTE_FLAG_DEFAULT;
56 return (hb_ot_color_palette_flags_t) (uint32_t)
57 (base+paletteFlagsZ).as_array (palette_count)[palette_index];
58 }
59
60 hb_ot_name_id_t get_palette_name_id (const void *base,
61 unsigned int palette_index,
62 unsigned int palette_count) const
63 {
64 if (!paletteLabelsZ) return HB_OT_NAME_ID_INVALID;
65 return (base+paletteLabelsZ).as_array (palette_count)[palette_index];
66 }
67
68 hb_ot_name_id_t get_color_name_id (const void *base,
69 unsigned int color_index,
70 unsigned int color_count) const
71 {
72 if (!colorLabelsZ) return HB_OT_NAME_ID_INVALID;
73 return (base+colorLabelsZ).as_array (color_count)[color_index];
74 }
75
76 public:
77 bool sanitize (hb_sanitize_context_t *c,
78 const void *base,
79 unsigned int palette_count,
80 unsigned int color_count) const
81 {
82 TRACE_SANITIZE (this);
83 return_trace (c->check_struct (this) &&
84 (!paletteFlagsZ || (base+paletteFlagsZ).sanitize (c, palette_count)) &&
85 (!paletteLabelsZ || (base+paletteLabelsZ).sanitize (c, palette_count)) &&
86 (!colorLabelsZ || (base+colorLabelsZ).sanitize (c, color_count)));
87 }
88
89 protected:
90 LNNOffsetTo<UnsizedArrayOf<HBUINT32> >
91 paletteFlagsZ; /* Offset from the beginning of CPAL table to
92 * the Palette Type Array. Set to 0 if no array
93 * is provided. */
94 LNNOffsetTo<UnsizedArrayOf<NameID> >
95 paletteLabelsZ; /* Offset from the beginning of CPAL table to
96 * the palette labels array. Set to 0 if no
97 * array is provided. */
98 LNNOffsetTo<UnsizedArrayOf<NameID> >
99 colorLabelsZ; /* Offset from the beginning of CPAL table to
100 * the color labels array. Set to 0
101 * if no array is provided. */
102 public:
103 DEFINE_SIZE_STATIC (12);
104 };
105
106 typedef HBUINT32 BGRAColor;
107
108 struct CPAL
109 {
110 static constexpr hb_tag_t tableTag = HB_OT_TAG_CPAL;
111
112 bool has_data () const { return numPalettes; }
113
114 unsigned int get_size () const
115 { return min_size + numPalettes * sizeof (colorRecordIndicesZ[0]); }
116
117 unsigned int get_palette_count () const { return numPalettes; }
118 unsigned int get_color_count () const { return numColors; }
119
120 hb_ot_color_palette_flags_t get_palette_flags (unsigned int palette_index) const
121 { return v1 ().get_palette_flags (this, palette_index, numPalettes); }
122
123 hb_ot_name_id_t get_palette_name_id (unsigned int palette_index) const
124 { return v1 ().get_palette_name_id (this, palette_index, numPalettes); }
125
126 hb_ot_name_id_t get_color_name_id (unsigned int color_index) const
127 { return v1 ().get_color_name_id (this, color_index, numColors); }
128
129 unsigned int get_palette_colors (unsigned int palette_index,
130 unsigned int start_offset,
131 unsigned int *color_count, /* IN/OUT. May be NULL. */
132 hb_color_t *colors /* OUT. May be NULL. */) const
133 {
134 if (unlikely (palette_index >= numPalettes))
135 {
136 if (color_count) *color_count = 0;
137 return 0;
138 }
139 unsigned int start_index = colorRecordIndicesZ[palette_index];
140 hb_array_t<const BGRAColor> all_colors ((this+colorRecordsZ).arrayZ, numColorRecords);
141 hb_array_t<const BGRAColor> palette_colors = all_colors.sub_array (start_index,
142 numColors);
143 if (color_count)
144 {
145 hb_array_t<const BGRAColor> segment_colors = palette_colors.sub_array (start_offset, *color_count);
146 /* Always return numColors colors per palette even if it has out-of-bounds start index. */
147 unsigned int count = MIN<unsigned int> (MAX<int> (numColors - start_offset, 0), *color_count);
148 *color_count = count;
149 for (unsigned int i = 0; i < count; i++)
150 colors[i] = segment_colors[i]; /* Bound-checked read. */
151 }
152 return numColors;
153 }
154
155 private:
156 const CPALV1Tail& v1 () const
157 {
158 if (version == 0) return Null(CPALV1Tail);
159 return StructAfter<CPALV1Tail> (*this);
160 }
161
162 public:
163 bool sanitize (hb_sanitize_context_t *c) const
164 {
165 TRACE_SANITIZE (this);
166 return_trace (c->check_struct (this) &&
167 (this+colorRecordsZ).sanitize (c, numColorRecords) &&
168 colorRecordIndicesZ.sanitize (c, numPalettes) &&
169 (version == 0 || v1 ().sanitize (c, this, numPalettes, numColors)));
170 }
171
172 protected:
173 HBUINT16 version; /* Table version number */
174 /* Version 0 */
175 HBUINT16 numColors; /* Number of colors in each palette. */
176 HBUINT16 numPalettes; /* Number of palettes in the table. */
177 HBUINT16 numColorRecords; /* Total number of color records, combined for
178 * all palettes. */
179 LNNOffsetTo<UnsizedArrayOf<BGRAColor> >
180 colorRecordsZ; /* Offset from the beginning of CPAL table to
181 * the first ColorRecord. */
182 UnsizedArrayOf<HBUINT16>
183 colorRecordIndicesZ; /* Index of each palette’s first color record in
184 * the combined color record array. */
185 /*CPALV1Tail v1;*/
186 public:
187 DEFINE_SIZE_ARRAY (12, colorRecordIndicesZ);
188 };
189
190 } /* namespace OT */
191
192
193 #endif /* HB_OT_COLOR_CPAL_TABLE_HH */