1 /*
2 * Copyright © 2011 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 FONT_OPTIONS_HH
28 #define FONT_OPTIONS_HH
29
30 #include "face-options.hh"
31
32 #ifdef HAVE_FREETYPE
33 #include <hb-ft.h>
34 #endif
35 #include <hb-ot.h>
36
37 #define FONT_SIZE_UPEM 0x7FFFFFFF
38 #define FONT_SIZE_NONE 0
39
40 extern const unsigned DEFAULT_FONT_SIZE;
41 extern const unsigned SUBPIXEL_BITS;
42
43 struct font_options_t : face_options_t
44 {
~font_options_tfont_options_t45 ~font_options_t ()
46 {
47 #ifndef HB_NO_VAR
48 free (variations);
49 #endif
50 g_free (font_funcs);
51 hb_font_destroy (font);
52 }
53
54 void add_options (option_parser_t *parser);
55
56 void post_parse (GError **error);
57
58 hb_bool_t sub_font = false;
59 #ifndef HB_NO_VAR
60 hb_variation_t *variations = nullptr;
61 unsigned int num_variations = 0;
62 #endif
63 int x_ppem = 0;
64 int y_ppem = 0;
65 double ptem = 0.;
66 double slant = 0.;
67 unsigned int subpixel_bits = SUBPIXEL_BITS;
68 mutable double font_size_x = DEFAULT_FONT_SIZE;
69 mutable double font_size_y = DEFAULT_FONT_SIZE;
70 char *font_funcs = nullptr;
71 int ft_load_flags = 2;
72
73 hb_font_t *font = nullptr;
74 };
75
76
77 static struct supported_font_funcs_t {
78 char name[4];
79 void (*func) (hb_font_t *);
80 } supported_font_funcs[] =
81 {
82 {"ot", hb_ot_font_set_funcs},
83 #ifdef HAVE_FREETYPE
84 {"ft", hb_ft_font_set_funcs},
85 #endif
86 };
87
88
89 void
post_parse(GError ** error)90 font_options_t::post_parse (GError **error)
91 {
92 assert (!font);
93 font = hb_font_create (face);
94
95 if (font_size_x == FONT_SIZE_UPEM)
96 font_size_x = hb_face_get_upem (face);
97 if (font_size_y == FONT_SIZE_UPEM)
98 font_size_y = hb_face_get_upem (face);
99
100 hb_font_set_ppem (font, x_ppem, y_ppem);
101 hb_font_set_ptem (font, ptem);
102
103 hb_font_set_synthetic_slant (font, slant);
104
105 int scale_x = (int) scalbnf (font_size_x, subpixel_bits);
106 int scale_y = (int) scalbnf (font_size_y, subpixel_bits);
107 hb_font_set_scale (font, scale_x, scale_y);
108
109 #ifndef HB_NO_VAR
110 hb_font_set_variations (font, variations, num_variations);
111 #endif
112
113 void (*set_font_funcs) (hb_font_t *) = nullptr;
114 if (!font_funcs)
115 {
116 set_font_funcs = supported_font_funcs[0].func;
117 }
118 else
119 {
120 for (unsigned int i = 0; i < ARRAY_LENGTH (supported_font_funcs); i++)
121 if (0 == g_ascii_strcasecmp (font_funcs, supported_font_funcs[i].name))
122 {
123 set_font_funcs = supported_font_funcs[i].func;
124 break;
125 }
126 if (!set_font_funcs)
127 {
128 GString *s = g_string_new (nullptr);
129 for (unsigned int i = 0; i < ARRAY_LENGTH (supported_font_funcs); i++)
130 {
131 if (i)
132 g_string_append_c (s, '/');
133 g_string_append (s, supported_font_funcs[i].name);
134 }
135 g_string_append_c (s, '\n');
136 char *p = g_string_free (s, FALSE);
137 g_set_error (error, G_OPTION_ERROR, G_OPTION_ERROR_BAD_VALUE,
138 "Unknown font function implementation `%s'; supported values are: %s; default is %s",
139 font_funcs,
140 p,
141 supported_font_funcs[0].name);
142 free (p);
143 return;
144 }
145 }
146 set_font_funcs (font);
147 #ifdef HAVE_FREETYPE
148 hb_ft_font_set_load_flags (font, ft_load_flags);
149 #endif
150
151 if (sub_font)
152 {
153 hb_font_t *old_font = font;
154 font = hb_font_create_sub_font (old_font);
155 hb_font_set_scale (old_font, scale_x * 2, scale_y * 2);
156 hb_font_destroy (old_font);
157 }
158 }
159
160
161 #ifndef HB_NO_VAR
162 static gboolean
parse_variations(const char * name G_GNUC_UNUSED,const char * arg,gpointer data,GError ** error G_GNUC_UNUSED)163 parse_variations (const char *name G_GNUC_UNUSED,
164 const char *arg,
165 gpointer data,
166 GError **error G_GNUC_UNUSED)
167 {
168 font_options_t *font_opts = (font_options_t *) data;
169 char *s = (char *) arg;
170 char *p;
171
172 font_opts->num_variations = 0;
173 g_free (font_opts->variations);
174 font_opts->variations = nullptr;
175
176 if (!*s)
177 return true;
178
179 /* count the variations first, so we can allocate memory */
180 p = s;
181 do {
182 font_opts->num_variations++;
183 p = strpbrk (p, ", ");
184 if (p)
185 p++;
186 } while (p);
187
188 font_opts->variations = (hb_variation_t *) calloc (font_opts->num_variations, sizeof (*font_opts->variations));
189 if (!font_opts->variations)
190 return false;
191
192 /* now do the actual parsing */
193 p = s;
194 font_opts->num_variations = 0;
195 while (p && *p) {
196 char *end = strpbrk (p, ", ");
197 if (hb_variation_from_string (p, end ? end - p : -1, &font_opts->variations[font_opts->num_variations]))
198 font_opts->num_variations++;
199 p = end ? end + 1 : nullptr;
200 }
201
202 return true;
203 }
204 #endif
205
206 static gboolean
parse_font_size(const char * name G_GNUC_UNUSED,const char * arg,gpointer data,GError ** error G_GNUC_UNUSED)207 parse_font_size (const char *name G_GNUC_UNUSED,
208 const char *arg,
209 gpointer data,
210 GError **error G_GNUC_UNUSED)
211 {
212 font_options_t *font_opts = (font_options_t *) data;
213 if (0 == strcmp (arg, "upem"))
214 {
215 font_opts->font_size_y = font_opts->font_size_x = FONT_SIZE_UPEM;
216 return true;
217 }
218 switch (sscanf (arg, "%lf%*[ ,]%lf", &font_opts->font_size_x, &font_opts->font_size_y)) {
219 case 1: font_opts->font_size_y = font_opts->font_size_x; HB_FALLTHROUGH;
220 case 2: return true;
221 default:
222 g_set_error (error, G_OPTION_ERROR, G_OPTION_ERROR_BAD_VALUE,
223 "%s argument should be one or two space-separated numbers",
224 name);
225 return false;
226 }
227 }
228
229 static gboolean
parse_font_ppem(const char * name G_GNUC_UNUSED,const char * arg,gpointer data,GError ** error G_GNUC_UNUSED)230 parse_font_ppem (const char *name G_GNUC_UNUSED,
231 const char *arg,
232 gpointer data,
233 GError **error G_GNUC_UNUSED)
234 {
235 font_options_t *font_opts = (font_options_t *) data;
236 switch (sscanf (arg, "%d%*[ ,]%d", &font_opts->x_ppem, &font_opts->y_ppem)) {
237 case 1: font_opts->y_ppem = font_opts->x_ppem; HB_FALLTHROUGH;
238 case 2: return true;
239 default:
240 g_set_error (error, G_OPTION_ERROR, G_OPTION_ERROR_BAD_VALUE,
241 "%s argument should be one or two space-separated numbers",
242 name);
243 return false;
244 }
245 }
246
247 void
add_options(option_parser_t * parser)248 font_options_t::add_options (option_parser_t *parser)
249 {
250 face_options_t::add_options (parser);
251
252 char *text = nullptr;
253
254 {
255 static_assert ((ARRAY_LENGTH_CONST (supported_font_funcs) > 0),
256 "No supported font-funcs found.");
257 GString *s = g_string_new (nullptr);
258 g_string_printf (s, "Set font functions implementation to use (default: %s)\n\n Supported font function implementations are: %s",
259 supported_font_funcs[0].name,
260 supported_font_funcs[0].name);
261 for (unsigned int i = 1; i < ARRAY_LENGTH (supported_font_funcs); i++)
262 {
263 g_string_append_c (s, '/');
264 g_string_append (s, supported_font_funcs[i].name);
265 }
266 text = g_string_free (s, FALSE);
267 parser->free_later (text);
268 }
269
270 char *font_size_text;
271 if (DEFAULT_FONT_SIZE == FONT_SIZE_UPEM)
272 font_size_text = (char *) "Font size (default: upem)";
273 else
274 {
275 font_size_text = g_strdup_printf ("Font size (default: %d)", DEFAULT_FONT_SIZE);
276 parser->free_later (font_size_text);
277 }
278
279 int font_size_flags = DEFAULT_FONT_SIZE == FONT_SIZE_NONE ? G_OPTION_FLAG_HIDDEN : 0;
280 GOptionEntry entries[] =
281 {
282 {"font-size", 0, font_size_flags,
283 G_OPTION_ARG_CALLBACK, (gpointer) &parse_font_size, font_size_text, "1/2 integers or 'upem'"},
284 {"font-ppem", 0, font_size_flags,
285 G_OPTION_ARG_CALLBACK, (gpointer) &parse_font_ppem, "Set x,y pixels per EM (default: 0; disabled)", "1/2 integers"},
286 {"font-ptem", 0, 0,
287 G_OPTION_ARG_DOUBLE, &this->ptem, "Set font point-size (default: 0; disabled)", "point-size"},
288 {"font-slant", 0, 0,
289 G_OPTION_ARG_DOUBLE, &this->slant, "Set synthetic slant (default: 0)", "slant ratio; eg. 0.2"},
290 {"font-funcs", 0, 0, G_OPTION_ARG_STRING, &this->font_funcs, text, "impl"},
291 {"sub-font", 0, G_OPTION_FLAG_HIDDEN,
292 G_OPTION_ARG_NONE, &this->sub_font, "Create a sub-font (default: false)", "boolean"},
293 {"ft-load-flags", 0, 0, G_OPTION_ARG_INT, &this->ft_load_flags, "Set FreeType load-flags (default: 2)", "integer"},
294 {nullptr}
295 };
296 parser->add_group (entries,
297 "font",
298 "Font-instance options:",
299 "Options for the font instance",
300 this,
301 false /* We add below. */);
302
303 #ifndef HB_NO_VAR
304 const gchar *variations_help = "Comma-separated list of font variations\n"
305 "\n"
306 " Variations are set globally. The format for specifying variation settings\n"
307 " follows. All valid CSS font-variation-settings values other than 'normal'\n"
308 " and 'inherited' are also accepted, though, not documented below.\n"
309 "\n"
310 " The format is a tag, optionally followed by an equals sign, followed by a\n"
311 " number. For example:\n"
312 "\n"
313 " \"wght=500\"\n"
314 " \"slnt=-7.5\"";
315
316 GOptionEntry entries2[] =
317 {
318 {"variations", 0, 0, G_OPTION_ARG_CALLBACK, (gpointer) &parse_variations, variations_help, "list"},
319 {nullptr}
320 };
321 parser->add_group (entries2,
322 "variations",
323 "Variations options:",
324 "Options for font variations used",
325 this);
326 #endif
327 }
328
329 #endif
330