1 /****************************************************************************
2 *
3 * wofftypes.h
4 *
5 * Basic WOFF/WOFF2 type definitions and interface (specification
6 * only).
7 *
8 * Copyright (C) 1996-2020 by
9 * David Turner, Robert Wilhelm, and Werner Lemberg.
10 *
11 * This file is part of the FreeType project, and may only be used,
12 * modified, and distributed under the terms of the FreeType project
13 * license, LICENSE.TXT. By continuing to use, modify, or distribute
14 * this file you indicate that you have read the license and
15 * understand and accept it fully.
16 *
17 */
18
19
20 #ifndef WOFFTYPES_H_
21 #define WOFFTYPES_H_
22
23
24 #include <ft2build.h>
25 #include FT_TRUETYPE_TABLES_H
26 #include FT_INTERNAL_OBJECTS_H
27
28
29 FT_BEGIN_HEADER
30
31
32 /**************************************************************************
33 *
34 * @struct:
35 * WOFF_HeaderRec
36 *
37 * @description:
38 * WOFF file format header.
39 *
40 * @fields:
41 * See
42 *
43 * https://www.w3.org/TR/WOFF/#WOFFHeader
44 */
45 typedef struct WOFF_HeaderRec_
46 {
47 FT_ULong signature;
48 FT_ULong flavor;
49 FT_ULong length;
50 FT_UShort num_tables;
51 FT_UShort reserved;
52 FT_ULong totalSfntSize;
53 FT_UShort majorVersion;
54 FT_UShort minorVersion;
55 FT_ULong metaOffset;
56 FT_ULong metaLength;
57 FT_ULong metaOrigLength;
58 FT_ULong privOffset;
59 FT_ULong privLength;
60
61 } WOFF_HeaderRec, *WOFF_Header;
62
63
64 /**************************************************************************
65 *
66 * @struct:
67 * WOFF_TableRec
68 *
69 * @description:
70 * This structure describes a given table of a WOFF font.
71 *
72 * @fields:
73 * Tag ::
74 * A four-bytes tag describing the table.
75 *
76 * Offset ::
77 * The offset of the table from the start of the WOFF font in its
78 * resource.
79 *
80 * CompLength ::
81 * Compressed table length (in bytes).
82 *
83 * OrigLength ::
84 * Uncompressed table length (in bytes).
85 *
86 * CheckSum ::
87 * The table checksum. This value can be ignored.
88 *
89 * OrigOffset ::
90 * The uncompressed table file offset. This value gets computed while
91 * constructing the (uncompressed) SFNT header. It is not contained in
92 * the WOFF file.
93 */
94 typedef struct WOFF_TableRec_
95 {
96 FT_ULong Tag; /* table ID */
97 FT_ULong Offset; /* table file offset */
98 FT_ULong CompLength; /* compressed table length */
99 FT_ULong OrigLength; /* uncompressed table length */
100 FT_ULong CheckSum; /* uncompressed checksum */
101
102 FT_ULong OrigOffset; /* uncompressed table file offset */
103 /* (not in the WOFF file) */
104 } WOFF_TableRec, *WOFF_Table;
105
106
107 /**************************************************************************
108 *
109 * @struct:
110 * WOFF2_TtcFontRec
111 *
112 * @description:
113 * Metadata for a TTC font entry in WOFF2.
114 *
115 * @fields:
116 * flavor ::
117 * TTC font flavor.
118 *
119 * num_tables ::
120 * Number of tables in TTC, indicating number of elements in
121 * `table_indices`.
122 *
123 * table_indices ::
124 * Array of table indices for each TTC font.
125 */
126 typedef struct WOFF2_TtcFontRec_
127 {
128 FT_ULong flavor;
129 FT_UShort num_tables;
130 FT_UShort* table_indices;
131
132 } WOFF2_TtcFontRec, *WOFF2_TtcFont;
133
134
135 /**************************************************************************
136 *
137 * @struct:
138 * WOFF2_HeaderRec
139 *
140 * @description:
141 * WOFF2 file format header.
142 *
143 * @fields:
144 * See
145 *
146 * https://www.w3.org/TR/WOFF2/#woff20Header
147 *
148 * @note:
149 * We don't care about the fields `reserved`, `majorVersion` and
150 * `minorVersion`, so they are not included. The `totalSfntSize` field
151 * does not necessarily represent the actual size of the uncompressed
152 * SFNT font stream, so that is used as a reference value instead.
153 */
154 typedef struct WOFF2_HeaderRec_
155 {
156 FT_ULong signature;
157 FT_ULong flavor;
158 FT_ULong length;
159 FT_UShort num_tables;
160 FT_ULong totalSfntSize;
161 FT_ULong totalCompressedSize;
162 FT_ULong metaOffset;
163 FT_ULong metaLength;
164 FT_ULong metaOrigLength;
165 FT_ULong privOffset;
166 FT_ULong privLength;
167
168 FT_ULong uncompressed_size; /* uncompressed brotli stream size */
169 FT_ULong compressed_offset; /* compressed stream offset */
170 FT_ULong header_version; /* version of original TTC Header */
171 FT_UShort num_fonts; /* number of fonts in TTC */
172 FT_ULong actual_sfnt_size; /* actual size of sfnt stream */
173
174 WOFF2_TtcFont ttc_fonts; /* metadata for fonts in a TTC */
175
176 } WOFF2_HeaderRec, *WOFF2_Header;
177
178
179 /**************************************************************************
180 *
181 * @struct:
182 * WOFF2_TableRec
183 *
184 * @description:
185 * This structure describes a given table of a WOFF2 font.
186 *
187 * @fields:
188 * See
189 *
190 * https://www.w3.org/TR/WOFF2/#table_dir_format
191 */
192 typedef struct WOFF2_TableRec_
193 {
194 FT_Byte FlagByte; /* table type and flags */
195 FT_ULong Tag; /* table file offset */
196 FT_ULong dst_length; /* uncompressed table length */
197 FT_ULong TransformLength; /* transformed length */
198
199 FT_ULong flags; /* calculated flags */
200 FT_ULong src_offset; /* compressed table offset */
201 FT_ULong src_length; /* compressed table length */
202 FT_ULong dst_offset; /* uncompressed table offset */
203
204 } WOFF2_TableRec, *WOFF2_Table;
205
206
207 /**************************************************************************
208 *
209 * @struct:
210 * WOFF2_InfoRec
211 *
212 * @description:
213 * Metadata for WOFF2 font that may be required for reconstruction of
214 * sfnt tables.
215 *
216 * @fields:
217 * header_checksum ::
218 * Checksum of SFNT offset table.
219 *
220 * num_glyphs ::
221 * Number of glyphs in the font.
222 *
223 * num_hmetrics ::
224 * `numberOfHMetrics` field in the 'hhea' table.
225 *
226 * x_mins ::
227 * `xMin` values of glyph bounding box.
228 *
229 * glyf_table ::
230 * A pointer to the `glyf' table record.
231 *
232 * loca_table ::
233 * A pointer to the `loca' table record.
234 *
235 * head_table ::
236 * A pointer to the `head' table record.
237 */
238 typedef struct WOFF2_InfoRec_
239 {
240 FT_ULong header_checksum;
241 FT_UShort num_glyphs;
242 FT_UShort num_hmetrics;
243 FT_Short* x_mins;
244
245 WOFF2_Table glyf_table;
246 WOFF2_Table loca_table;
247 WOFF2_Table head_table;
248
249 } WOFF2_InfoRec, *WOFF2_Info;
250
251
252 /**************************************************************************
253 *
254 * @struct:
255 * WOFF2_SubstreamRec
256 *
257 * @description:
258 * This structure stores information about a substream in the transformed
259 * 'glyf' table in a WOFF2 stream.
260 *
261 * @fields:
262 * start ::
263 * Beginning of the substream relative to uncompressed table stream.
264 *
265 * offset ::
266 * Offset of the substream relative to uncompressed table stream.
267 *
268 * size ::
269 * Size of the substream.
270 */
271 typedef struct WOFF2_SubstreamRec_
272 {
273 FT_ULong start;
274 FT_ULong offset;
275 FT_ULong size;
276
277 } WOFF2_SubstreamRec, *WOFF2_Substream;
278
279
280 /**************************************************************************
281 *
282 * @struct:
283 * WOFF2_PointRec
284 *
285 * @description:
286 * This structure stores information about a point in the transformed
287 * 'glyf' table in a WOFF2 stream.
288 *
289 * @fields:
290 * x ::
291 * x-coordinate of point.
292 *
293 * y ::
294 * y-coordinate of point.
295 *
296 * on_curve ::
297 * Set if point is on-curve.
298 */
299 typedef struct WOFF2_PointRec_
300 {
301 FT_Int x;
302 FT_Int y;
303 FT_Bool on_curve;
304
305 } WOFF2_PointRec, *WOFF2_Point;
306
307
308 FT_END_HEADER
309
310 #endif /* WOFFTYPES_H_ */
311
312
313 /* END */