1 | /**************************************************************************** |
2 | * |
3 | * ttcpal.c |
4 | * |
5 | * TrueType and OpenType color palette support (body). |
6 | * |
7 | * Copyright (C) 2018-2023 by |
8 | * David Turner, Robert Wilhelm, and Werner Lemberg. |
9 | * |
10 | * Originally written by Shao Yu Zhang <shaozhang@fb.com>. |
11 | * |
12 | * This file is part of the FreeType project, and may only be used, |
13 | * modified, and distributed under the terms of the FreeType project |
14 | * license, LICENSE.TXT. By continuing to use, modify, or distribute |
15 | * this file you indicate that you have read the license and |
16 | * understand and accept it fully. |
17 | * |
18 | */ |
19 | |
20 | |
21 | /************************************************************************** |
22 | * |
23 | * `CPAL' table specification: |
24 | * |
25 | * https://www.microsoft.com/typography/otspec/cpal.htm |
26 | * |
27 | */ |
28 | |
29 | |
30 | #include <freetype/internal/ftdebug.h> |
31 | #include <freetype/internal/ftstream.h> |
32 | #include <freetype/tttags.h> |
33 | #include <freetype/ftcolor.h> |
34 | |
35 | |
36 | #ifdef TT_CONFIG_OPTION_COLOR_LAYERS |
37 | |
38 | #include "ttcpal.h" |
39 | |
40 | |
41 | /* NOTE: These are the table sizes calculated through the specs. */ |
42 | #define 12U |
43 | #define COLOR_SIZE 4U |
44 | |
45 | |
46 | /* all data from `CPAL' not covered in FT_Palette_Data */ |
47 | typedef struct Cpal_ |
48 | { |
49 | FT_UShort version; /* Table version number (0 or 1 supported). */ |
50 | FT_UShort num_colors; /* Total number of color records, */ |
51 | /* combined for all palettes. */ |
52 | FT_Byte* colors; /* RGBA array of colors */ |
53 | FT_Byte* color_indices; /* Index of each palette's first color record */ |
54 | /* in the combined color record array. */ |
55 | |
56 | /* The memory which backs up the `CPAL' table. */ |
57 | void* table; |
58 | FT_ULong table_size; |
59 | |
60 | } Cpal; |
61 | |
62 | |
63 | /************************************************************************** |
64 | * |
65 | * The macro FT_COMPONENT is used in trace mode. It is an implicit |
66 | * parameter of the FT_TRACE() and FT_ERROR() macros, used to print/log |
67 | * messages during execution. |
68 | */ |
69 | #undef FT_COMPONENT |
70 | #define FT_COMPONENT ttcpal |
71 | |
72 | |
73 | FT_LOCAL_DEF( FT_Error ) |
74 | tt_face_load_cpal( TT_Face face, |
75 | FT_Stream stream ) |
76 | { |
77 | FT_Error error; |
78 | FT_Memory memory = face->root.memory; |
79 | |
80 | FT_Byte* table = NULL; |
81 | FT_Byte* p = NULL; |
82 | |
83 | Cpal* cpal = NULL; |
84 | |
85 | FT_ULong colors_offset; |
86 | FT_ULong table_size; |
87 | |
88 | |
89 | error = face->goto_table( face, TTAG_CPAL, stream, &table_size ); |
90 | if ( error ) |
91 | goto NoCpal; |
92 | |
93 | if ( table_size < CPAL_V0_HEADER_BASE_SIZE ) |
94 | goto InvalidTable; |
95 | |
96 | if ( FT_FRAME_EXTRACT( table_size, table ) ) |
97 | goto NoCpal; |
98 | |
99 | p = table; |
100 | |
101 | if ( FT_NEW( cpal ) ) |
102 | goto NoCpal; |
103 | |
104 | cpal->version = FT_NEXT_USHORT( p ); |
105 | if ( cpal->version > 1 ) |
106 | goto InvalidTable; |
107 | |
108 | face->palette_data.num_palette_entries = FT_NEXT_USHORT( p ); |
109 | face->palette_data.num_palettes = FT_NEXT_USHORT( p ); |
110 | |
111 | cpal->num_colors = FT_NEXT_USHORT( p ); |
112 | colors_offset = FT_NEXT_ULONG( p ); |
113 | |
114 | if ( CPAL_V0_HEADER_BASE_SIZE + |
115 | face->palette_data.num_palettes * 2U > table_size ) |
116 | goto InvalidTable; |
117 | |
118 | if ( colors_offset >= table_size ) |
119 | goto InvalidTable; |
120 | if ( cpal->num_colors * COLOR_SIZE > table_size - colors_offset ) |
121 | goto InvalidTable; |
122 | |
123 | if ( face->palette_data.num_palette_entries > cpal->num_colors ) |
124 | goto InvalidTable; |
125 | |
126 | cpal->color_indices = p; |
127 | cpal->colors = (FT_Byte*)( table + colors_offset ); |
128 | |
129 | if ( cpal->version == 1 ) |
130 | { |
131 | FT_ULong type_offset, label_offset, entry_label_offset; |
132 | FT_UShort* array = NULL; |
133 | FT_UShort* limit; |
134 | FT_UShort* q; |
135 | |
136 | |
137 | if ( CPAL_V0_HEADER_BASE_SIZE + |
138 | face->palette_data.num_palettes * 2U + |
139 | 3U * 4 > table_size ) |
140 | goto InvalidTable; |
141 | |
142 | p += face->palette_data.num_palettes * 2U; |
143 | |
144 | type_offset = FT_NEXT_ULONG( p ); |
145 | label_offset = FT_NEXT_ULONG( p ); |
146 | entry_label_offset = FT_NEXT_ULONG( p ); |
147 | |
148 | if ( type_offset ) |
149 | { |
150 | if ( type_offset >= table_size ) |
151 | goto InvalidTable; |
152 | if ( face->palette_data.num_palettes * 2U > |
153 | table_size - type_offset ) |
154 | goto InvalidTable; |
155 | |
156 | if ( FT_QNEW_ARRAY( array, face->palette_data.num_palettes ) ) |
157 | goto NoCpal; |
158 | |
159 | p = table + type_offset; |
160 | q = array; |
161 | limit = q + face->palette_data.num_palettes; |
162 | |
163 | while ( q < limit ) |
164 | *q++ = FT_NEXT_USHORT( p ); |
165 | |
166 | face->palette_data.palette_flags = array; |
167 | } |
168 | |
169 | if ( label_offset ) |
170 | { |
171 | if ( label_offset >= table_size ) |
172 | goto InvalidTable; |
173 | if ( face->palette_data.num_palettes * 2U > |
174 | table_size - label_offset ) |
175 | goto InvalidTable; |
176 | |
177 | if ( FT_QNEW_ARRAY( array, face->palette_data.num_palettes ) ) |
178 | goto NoCpal; |
179 | |
180 | p = table + label_offset; |
181 | q = array; |
182 | limit = q + face->palette_data.num_palettes; |
183 | |
184 | while ( q < limit ) |
185 | *q++ = FT_NEXT_USHORT( p ); |
186 | |
187 | face->palette_data.palette_name_ids = array; |
188 | } |
189 | |
190 | if ( entry_label_offset ) |
191 | { |
192 | if ( entry_label_offset >= table_size ) |
193 | goto InvalidTable; |
194 | if ( face->palette_data.num_palette_entries * 2U > |
195 | table_size - entry_label_offset ) |
196 | goto InvalidTable; |
197 | |
198 | if ( FT_QNEW_ARRAY( array, face->palette_data.num_palette_entries ) ) |
199 | goto NoCpal; |
200 | |
201 | p = table + entry_label_offset; |
202 | q = array; |
203 | limit = q + face->palette_data.num_palette_entries; |
204 | |
205 | while ( q < limit ) |
206 | *q++ = FT_NEXT_USHORT( p ); |
207 | |
208 | face->palette_data.palette_entry_name_ids = array; |
209 | } |
210 | } |
211 | |
212 | cpal->table = table; |
213 | cpal->table_size = table_size; |
214 | |
215 | face->cpal = cpal; |
216 | |
217 | /* set up default palette */ |
218 | if ( FT_NEW_ARRAY( face->palette, |
219 | face->palette_data.num_palette_entries ) ) |
220 | goto NoCpal; |
221 | |
222 | if ( tt_face_palette_set( face, 0 ) ) |
223 | goto InvalidTable; |
224 | |
225 | return FT_Err_Ok; |
226 | |
227 | InvalidTable: |
228 | error = FT_THROW( Invalid_Table ); |
229 | |
230 | NoCpal: |
231 | FT_FRAME_RELEASE( table ); |
232 | FT_FREE( cpal ); |
233 | |
234 | face->cpal = NULL; |
235 | |
236 | /* arrays in `face->palette_data' and `face->palette' */ |
237 | /* are freed in `sfnt_done_face' */ |
238 | |
239 | return error; |
240 | } |
241 | |
242 | |
243 | FT_LOCAL_DEF( void ) |
244 | tt_face_free_cpal( TT_Face face ) |
245 | { |
246 | FT_Stream stream = face->root.stream; |
247 | FT_Memory memory = face->root.memory; |
248 | |
249 | Cpal* cpal = (Cpal*)face->cpal; |
250 | |
251 | |
252 | if ( cpal ) |
253 | { |
254 | FT_FRAME_RELEASE( cpal->table ); |
255 | FT_FREE( cpal ); |
256 | } |
257 | } |
258 | |
259 | |
260 | FT_LOCAL_DEF( FT_Error ) |
261 | tt_face_palette_set( TT_Face face, |
262 | FT_UInt palette_index ) |
263 | { |
264 | Cpal* cpal = (Cpal*)face->cpal; |
265 | |
266 | FT_Byte* offset; |
267 | FT_Byte* p; |
268 | |
269 | FT_Color* q; |
270 | FT_Color* limit; |
271 | |
272 | FT_UShort color_index; |
273 | |
274 | |
275 | if ( !cpal || palette_index >= face->palette_data.num_palettes ) |
276 | return FT_THROW( Invalid_Argument ); |
277 | |
278 | offset = cpal->color_indices + 2 * palette_index; |
279 | color_index = FT_PEEK_USHORT( offset ); |
280 | |
281 | if ( color_index + face->palette_data.num_palette_entries > |
282 | cpal->num_colors ) |
283 | return FT_THROW( Invalid_Table ); |
284 | |
285 | p = cpal->colors + COLOR_SIZE * color_index; |
286 | q = face->palette; |
287 | limit = q + face->palette_data.num_palette_entries; |
288 | |
289 | while ( q < limit ) |
290 | { |
291 | q->blue = FT_NEXT_BYTE( p ); |
292 | q->green = FT_NEXT_BYTE( p ); |
293 | q->red = FT_NEXT_BYTE( p ); |
294 | q->alpha = FT_NEXT_BYTE( p ); |
295 | |
296 | q++; |
297 | } |
298 | |
299 | return FT_Err_Ok; |
300 | } |
301 | |
302 | |
303 | #else /* !TT_CONFIG_OPTION_COLOR_LAYERS */ |
304 | |
305 | /* ANSI C doesn't like empty source files */ |
306 | typedef int tt_cpal_dummy_; |
307 | |
308 | #endif /* !TT_CONFIG_OPTION_COLOR_LAYERS */ |
309 | |
310 | /* EOF */ |
311 | |