1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
|
/*
* Copyright (C) 2006 Evgeniy Stepanov <eugeni.stepanov@gmail.com>
*
* This file is part of libass.
*
* Permission to use, copy, modify, and distribute this software for any
* purpose with or without fee is hereby granted, provided that the above
* copyright notice and this permission notice appear in all copies.
*
* THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
* ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
* ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
* OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
*/
#ifndef LIBASS_FONTCONFIG_H
#define LIBASS_FONTCONFIG_H
#include <stdint.h>
#include <ft2build.h>
#include FT_FREETYPE_H
typedef struct ass_shaper_font_data ASS_ShaperFontData;
typedef struct font_selector ASS_FontSelector;
typedef struct font_info ASS_FontInfo;
#include "ass_types.h"
#include "ass.h"
#include "ass_font.h"
typedef struct font_provider ASS_FontProvider;
/* Font Provider */
typedef struct ass_font_provider_meta_data ASS_FontProviderMetaData;
/**
* Get font data. This is a stream interface which can be used as an
* alternative to providing a font path (which may not be available).
*
* This is called by fontselect if a given font was added without a
* font path (i.e. the path was set to NULL).
*
* \param font_priv font private data
* \param output buffer; set to NULL to query stream size
* \param offset stream offset
* \param len bytes to read into output buffer from stream
* \return actual number of bytes read, or stream size if data == NULL
*/
typedef size_t (*GetDataFunc)(void *font_priv, unsigned char *data,
size_t offset, size_t len);
/**
* Check if a glyph is supported by a font.
*
* \param font_priv font private data
* \param codepont Unicode codepoint (UTF-32)
* \return non-zero value if codepoint is supported by the font
*/
typedef int (*CheckGlyphFunc)(void *font_priv, uint32_t codepoint);
/**
* Destroy a font's private data.
*
* \param font_priv font private data
*/
typedef void (*DestroyFontFunc)(void *font_priv);
/**
* Destroy a font provider's private data.
*
* \param priv font provider private data
*/
typedef void (*DestroyProviderFunc)(void *priv);
/**
* Add fonts for a given font name; this should add all fonts matching the
* given name to the fontselect database.
*
* This is called by fontselect whenever a new logical font is created. The
* font provider set as default is used.
*
* \param lib ASS_Library instance
* \param provider font provider instance
* \param name font name (as specified in script)
*/
typedef void (*MatchFontsFunc)(ASS_Library *lib,
ASS_FontProvider *provider,
char *name);
/**
* Substitute font name by another. This implements generic font family
* substitutions (e.g. sans-serif, serif, monospace) as well as font aliases.
*
* The generic families should map to sensible platform-specific font families.
* Aliases are sometimes used to map from common fonts that don't exist on
* a particular platform to similar alternatives. For example, a Linux
* system with fontconfig may map "Arial" to "Liberation Sans" and Windows
* maps "Helvetica" to "Arial".
*
* This is called by fontselect when a new logical font is created. The font
* provider set as default is used.
*
* \param priv font provider private data
* \param name input string for substitution, as specified in the script
* \param meta metadata (fullnames and n_fullname) to be filled in
*/
typedef void (*SubstituteFontFunc)(void *priv, const char *name,
ASS_FontProviderMetaData *meta);
/**
* Get an appropriate fallback font for a given codepoint.
*
* This is called by fontselect whenever a glyph is not found in the
* physical font list of a logical font. fontselect will try to add the
* font family with match_fonts if it does not exist in the font list
* add match_fonts is not NULL. Note that the returned font family should
* contain the requested codepoint.
*
* Note that fontselect uses the font provider set as default to determine
* fallbacks.
*
* \param font_priv font private data
* \param codepoint Unicode codepoint (UTF-32)
* \return output font family, allocated with malloc(), must be freed
* by caller.
*/
typedef char *(*GetFallbackFunc)(void *font_priv,
ASS_FontProviderMetaData *meta,
uint32_t codepoint);
typedef struct font_provider_funcs {
GetDataFunc get_data; /* optional/mandatory */
CheckGlyphFunc check_glyph; /* mandatory */
DestroyFontFunc destroy_font; /* optional */
DestroyProviderFunc destroy_provider; /* optional */
MatchFontsFunc match_fonts; /* optional */
SubstituteFontFunc subst_font; /* optional */
GetFallbackFunc fallback_font; /* optional */
} ASS_FontProviderFuncs;
/*
* Basic font metadata. All strings must be encoded with UTF-8.
* At minimum one family is required.
*/
struct ass_font_provider_meta_data {
/**
* List of localized font family names, e.g. "Arial".
*/
char **families;
/**
* List of localized full names, e.g. "Arial Bold".
* The English name should be listed first to speed up typical matching.
*/
char **fullnames;
int n_family; // Number of localized family names
int n_fullname; // Number of localized full names
int slant; // Font slant value from FONT_SLANT_*
int weight; // Font weight in TrueType scale, 100-900
// See FONT_WEIGHT_*
int width; // Font weight in percent, normally 100
// See FONT_WIDTH_*
};
typedef struct ass_font_stream ASS_FontStream;
struct ass_font_stream {
// GetDataFunc
size_t (*func)(void *font_priv, unsigned char *data,
size_t offset, size_t len);
void *priv;
};
ASS_FontSelector *
ass_fontselect_init(ASS_Library *library,
FT_Library ftlibrary, const char *family,
const char *path, const char *config,
ASS_DefaultFontProvider dfp);
char *ass_font_select(ASS_FontSelector *priv, ASS_Library *library,
ASS_Font *font, int *index, char **postscript_name,
int *uid, ASS_FontStream *data, uint32_t code);
void ass_fontselect_free(ASS_FontSelector *priv);
// Font provider functions
ASS_FontProvider *ass_font_provider_new(ASS_FontSelector *selector,
ASS_FontProviderFuncs *funcs, void *data);
/**
* \brief Create an empty font provider. A font provider can be used to
* provide additional fonts to libass.
* \param priv parent renderer
* \param funcs callback functions
* \param private data for provider callbacks
*
*/
ASS_FontProvider *
ass_create_font_provider(ASS_Renderer *priv, ASS_FontProviderFuncs *funcs,
void *data);
/**
* \brief Add a font to a font provider.
* \param provider the font provider
* \param meta font metadata. See struct definition for more information.
* \param path absolute path to font, or NULL for memory-based fonts
* \param index index inside a font collection file
* \param psname PostScript name of the face (overrides index if present)
* \param data private data for font callbacks
* \return success
*
*/
int
ass_font_provider_add_font(ASS_FontProvider *provider,
ASS_FontProviderMetaData *meta, const char *path,
unsigned int index, const char *psname, void *data);
/**
* \brief Free font provider and associated fonts.
* \param provider the font provider
*
*/
void ass_font_provider_free(ASS_FontProvider *provider);
#endif /* LIBASS_FONTCONFIG_H */
|
