1 /*
2 * Copyright © 2009 Red Hat, Inc.
3 * Copyright © 2011 Google, Inc.
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 * Red Hat Author(s): Behdad Esfahbod
26 * Google Author(s): Behdad Esfahbod
27 */
28
29 #ifndef HB_FONT_PRIVATE_HH
30 #define HB_FONT_PRIVATE_HH
31
32 #include "hb-private.hh"
33
34 #include "hb-object-private.hh"
35 #include "hb-face-private.hh"
36 #include "hb-shaper-private.hh"
37
38
39
40 /*
41 * hb_font_funcs_t
42 */
43
44 #define HB_FONT_FUNCS_IMPLEMENT_CALLBACKS \
45 HB_FONT_FUNC_IMPLEMENT (glyph) \
46 HB_FONT_FUNC_IMPLEMENT (glyph_h_advance) \
47 HB_FONT_FUNC_IMPLEMENT (glyph_v_advance) \
48 HB_FONT_FUNC_IMPLEMENT (glyph_h_origin) \
49 HB_FONT_FUNC_IMPLEMENT (glyph_v_origin) \
50 HB_FONT_FUNC_IMPLEMENT (glyph_h_kerning) \
51 HB_FONT_FUNC_IMPLEMENT (glyph_v_kerning) \
52 HB_FONT_FUNC_IMPLEMENT (glyph_extents) \
53 HB_FONT_FUNC_IMPLEMENT (glyph_contour_point) \
54 HB_FONT_FUNC_IMPLEMENT (glyph_name) \
55 HB_FONT_FUNC_IMPLEMENT (glyph_from_name) \
56 /* ^--- Add new callbacks here */
57
58 struct hb_font_funcs_t {
59 hb_object_header_t header;
60 ASSERT_POD ();
61
62 hb_bool_t immutable;
63
64 /* Don't access these directly. Call hb_font_get_*() instead. */
65
66 struct {
67 #define HB_FONT_FUNC_IMPLEMENT(name) hb_font_get_##name##_func_t name;
68 HB_FONT_FUNCS_IMPLEMENT_CALLBACKS
69 #undef HB_FONT_FUNC_IMPLEMENT
70 } get;
71
72 struct {
73 #define HB_FONT_FUNC_IMPLEMENT(name) void *name;
74 HB_FONT_FUNCS_IMPLEMENT_CALLBACKS
75 #undef HB_FONT_FUNC_IMPLEMENT
76 } user_data;
77
78 struct {
79 #define HB_FONT_FUNC_IMPLEMENT(name) hb_destroy_func_t name;
80 HB_FONT_FUNCS_IMPLEMENT_CALLBACKS
81 #undef HB_FONT_FUNC_IMPLEMENT
82 } destroy;
83 };
84
85
86
87 /*
88 * hb_font_t
89 */
90
91 struct hb_font_t {
92 hb_object_header_t header;
93 ASSERT_POD ();
94
95 hb_bool_t immutable;
96
97 hb_font_t *parent;
98 hb_face_t *face;
99
100 int x_scale;
101 int y_scale;
102
103 unsigned int x_ppem;
104 unsigned int y_ppem;
105
106 hb_font_funcs_t *klass;
107 void *user_data;
108 hb_destroy_func_t destroy;
109
110 struct hb_shaper_data_t shaper_data;
111
112
113 /* Convert from font-space to user-space */
114 inline hb_position_t em_scale_x (int16_t v) { return em_scale (v, this->x_scale); }
115 inline hb_position_t em_scale_y (int16_t v) { return em_scale (v, this->y_scale); }
116
117 /* Convert from parent-font user-space to our user-space */
118 inline hb_position_t parent_scale_x_distance (hb_position_t v) {
119 if (unlikely (parent && parent->x_scale != x_scale))
120 return (hb_position_t) (v * (int64_t) this->x_scale / this->parent->x_scale);
121 return v;
122 }
123 inline hb_position_t parent_scale_y_distance (hb_position_t v) {
124 if (unlikely (parent && parent->y_scale != y_scale))
125 return (hb_position_t) (v * (int64_t) this->y_scale / this->parent->y_scale);
126 return v;
127 }
128 inline hb_position_t parent_scale_x_position (hb_position_t v) {
129 return parent_scale_x_distance (v);
130 }
131 inline hb_position_t parent_scale_y_position (hb_position_t v) {
132 return parent_scale_y_distance (v);
133 }
134
135 inline void parent_scale_distance (hb_position_t *x, hb_position_t *y) {
136 *x = parent_scale_x_distance (*x);
137 *y = parent_scale_y_distance (*y);
138 }
139 inline void parent_scale_position (hb_position_t *x, hb_position_t *y) {
140 *x = parent_scale_x_position (*x);
141 *y = parent_scale_y_position (*y);
142 }
143
144
145 /* Public getters */
146
147 inline hb_bool_t has_glyph (hb_codepoint_t unicode)
148 {
149 hb_codepoint_t glyph;
150 return get_glyph (unicode, 0, &glyph);
151 }
152
153 inline hb_bool_t get_glyph (hb_codepoint_t unicode, hb_codepoint_t variation_selector,
154 hb_codepoint_t *glyph)
155 {
156 *glyph = 0;
157 return klass->get.glyph (this, user_data,
158 unicode, variation_selector, glyph,
159 klass->user_data.glyph);
160 }
161
162 inline hb_position_t get_glyph_h_advance (hb_codepoint_t glyph)
163 {
164 return klass->get.glyph_h_advance (this, user_data,
165 glyph,
166 klass->user_data.glyph_h_advance);
167 }
168
169 inline hb_position_t get_glyph_v_advance (hb_codepoint_t glyph)
170 {
171 return klass->get.glyph_v_advance (this, user_data,
172 glyph,
173 klass->user_data.glyph_v_advance);
174 }
175
176 inline hb_bool_t get_glyph_h_origin (hb_codepoint_t glyph,
177 hb_position_t *x, hb_position_t *y)
178 {
179 *x = *y = 0;
180 return klass->get.glyph_h_origin (this, user_data,
181 glyph, x, y,
182 klass->user_data.glyph_h_origin);
183 }
184
185 inline hb_bool_t get_glyph_v_origin (hb_codepoint_t glyph,
186 hb_position_t *x, hb_position_t *y)
187 {
188 *x = *y = 0;
189 return klass->get.glyph_v_origin (this, user_data,
190 glyph, x, y,
191 klass->user_data.glyph_v_origin);
192 }
193
194 inline hb_position_t get_glyph_h_kerning (hb_codepoint_t left_glyph, hb_codepoint_t right_glyph)
195 {
196 return klass->get.glyph_h_kerning (this, user_data,
197 left_glyph, right_glyph,
198 klass->user_data.glyph_h_kerning);
199 }
200
201 inline hb_position_t get_glyph_v_kerning (hb_codepoint_t top_glyph, hb_codepoint_t bottom_glyph)
202 {
203 return klass->get.glyph_v_kerning (this, user_data,
204 top_glyph, bottom_glyph,
205 klass->user_data.glyph_v_kerning);
206 }
207
208 inline hb_bool_t get_glyph_extents (hb_codepoint_t glyph,
209 hb_glyph_extents_t *extents)
210 {
211 memset (extents, 0, sizeof (*extents));
212 return klass->get.glyph_extents (this, user_data,
213 glyph,
214 extents,
215 klass->user_data.glyph_extents);
216 }
217
218 inline hb_bool_t get_glyph_contour_point (hb_codepoint_t glyph, unsigned int point_index,
219 hb_position_t *x, hb_position_t *y)
220 {
221 *x = *y = 0;
222 return klass->get.glyph_contour_point (this, user_data,
223 glyph, point_index,
224 x, y,
225 klass->user_data.glyph_contour_point);
226 }
227
228 inline hb_bool_t get_glyph_name (hb_codepoint_t glyph,
229 char *name, unsigned int size)
230 {
231 if (size) *name = '\0';
232 return klass->get.glyph_name (this, user_data,
233 glyph,
234 name, size,
235 klass->user_data.glyph_name);
236 }
237
238 inline hb_bool_t get_glyph_from_name (const char *name, int len, /* -1 means nul-terminated */
239 hb_codepoint_t *glyph)
240 {
241 *glyph = 0;
242 if (len == -1) len = strlen (name);
243 return klass->get.glyph_from_name (this, user_data,
244 name, len,
245 glyph,
246 klass->user_data.glyph_from_name);
247 }
248
249
250 /* A bit higher-level, and with fallback */
251
252 inline void get_glyph_advance_for_direction (hb_codepoint_t glyph,
253 hb_direction_t direction,
254 hb_position_t *x, hb_position_t *y)
255 {
256 if (likely (HB_DIRECTION_IS_HORIZONTAL (direction))) {
257 *x = get_glyph_h_advance (glyph);
258 *y = 0;
259 } else {
260 *x = 0;
261 *y = get_glyph_v_advance (glyph);
262 }
263 }
264
265 /* Internal only */
266 inline void guess_v_origin_minus_h_origin (hb_codepoint_t glyph,
267 hb_position_t *x, hb_position_t *y)
268 {
269 *x = get_glyph_h_advance (glyph) / 2;
270
271 /* TODO use font_metrics.ascent */
272 *y = y_scale;
273 }
274
275 inline void get_glyph_origin_for_direction (hb_codepoint_t glyph,
276 hb_direction_t direction,
277 hb_position_t *x, hb_position_t *y)
278 {
279 if (likely (HB_DIRECTION_IS_HORIZONTAL (direction)))
280 {
281 if (!get_glyph_h_origin (glyph, x, y) &&
282 get_glyph_v_origin (glyph, x, y))
283 {
284 hb_position_t dx, dy;
285 guess_v_origin_minus_h_origin (glyph, &dx, &dy);
286 *x -= dx; *y -= dy;
287 }
288 }
289 else
290 {
291 if (!get_glyph_v_origin (glyph, x, y) &&
292 get_glyph_h_origin (glyph, x, y))
293 {
294 hb_position_t dx, dy;
295 guess_v_origin_minus_h_origin (glyph, &dx, &dy);
296 *x += dx; *y += dy;
297 }
298 }
299 }
300
301 inline void add_glyph_origin_for_direction (hb_codepoint_t glyph,
302 hb_direction_t direction,
303 hb_position_t *x, hb_position_t *y)
304 {
305 hb_position_t origin_x, origin_y;
306
307 get_glyph_origin_for_direction (glyph, direction, &origin_x, &origin_y);
308
309 *x += origin_x;
310 *y += origin_y;
311 }
312
313 inline void subtract_glyph_origin_for_direction (hb_codepoint_t glyph,
314 hb_direction_t direction,
315 hb_position_t *x, hb_position_t *y)
316 {
317 hb_position_t origin_x, origin_y;
318
319 get_glyph_origin_for_direction (glyph, direction, &origin_x, &origin_y);
320
321 *x -= origin_x;
322 *y -= origin_y;
323 }
324
325 inline void get_glyph_kerning_for_direction (hb_codepoint_t first_glyph, hb_codepoint_t second_glyph,
326 hb_direction_t direction,
327 hb_position_t *x, hb_position_t *y)
328 {
329 if (likely (HB_DIRECTION_IS_HORIZONTAL (direction))) {
330 *x = get_glyph_h_kerning (first_glyph, second_glyph);
331 *y = 0;
332 } else {
333 *x = 0;
334 *y = get_glyph_v_kerning (first_glyph, second_glyph);
335 }
336 }
337
338 inline hb_bool_t get_glyph_extents_for_origin (hb_codepoint_t glyph,
339 hb_direction_t direction,
340 hb_glyph_extents_t *extents)
341 {
342 hb_bool_t ret = get_glyph_extents (glyph, extents);
343
344 if (ret)
345 subtract_glyph_origin_for_direction (glyph, direction, &extents->x_bearing, &extents->y_bearing);
346
347 return ret;
348 }
349
350 inline hb_bool_t get_glyph_contour_point_for_origin (hb_codepoint_t glyph, unsigned int point_index,
351 hb_direction_t direction,
352 hb_position_t *x, hb_position_t *y)
353 {
354 hb_bool_t ret = get_glyph_contour_point (glyph, point_index, x, y);
355
356 if (ret)
357 subtract_glyph_origin_for_direction (glyph, direction, x, y);
358
359 return ret;
360 }
361
362 /* Generates gidDDD if glyph has no name. */
363 inline void
364 glyph_to_string (hb_codepoint_t glyph,
365 char *s, unsigned int size)
366 {
367 if (get_glyph_name (glyph, s, size)) return;
368
369 if (size && snprintf (s, size, "gid%u", glyph) < 0)
370 *s = '\0';
371 }
372
373 /* Parses gidDDD and uniUUUU strings automatically. */
374 inline hb_bool_t
375 glyph_from_string (const char *s, int len, /* -1 means nul-terminated */
376 hb_codepoint_t *glyph)
377 {
378 if (get_glyph_from_name (s, len, glyph)) return true;
379
380 if (len == -1) len = strlen (s);
381
382 /* Straight glyph index. */
383 if (hb_codepoint_parse (s, len, 10, glyph))
384 return true;
385
386 if (len > 3)
387 {
388 /* gidDDD syntax for glyph indices. */
389 if (0 == strncmp (s, "gid", 3) &&
390 hb_codepoint_parse (s + 3, len - 3, 10, glyph))
391 return true;
392
393 /* uniUUUU and other Unicode character indices. */
394 hb_codepoint_t unichar;
395 if (0 == strncmp (s, "uni", 3) &&
396 hb_codepoint_parse (s + 3, len - 3, 16, &unichar) &&
397 get_glyph (unichar, 0, glyph))
398 return true;
399 }
400
401 return false;
402 }
403
404 private:
405 inline hb_position_t em_scale (int16_t v, int scale) { return (hb_position_t) (v * (int64_t) scale / face->get_upem ()); }
406 };
407
408 #define HB_SHAPER_DATA_CREATE_FUNC_EXTRA_ARGS
409 #define HB_SHAPER_IMPLEMENT(shaper) HB_SHAPER_DATA_PROTOTYPE(shaper, font);
410 #include "hb-shaper-list.hh"
411 #undef HB_SHAPER_IMPLEMENT
412 #undef HB_SHAPER_DATA_CREATE_FUNC_EXTRA_ARGS
413
414
415 #endif /* HB_FONT_PRIVATE_HH */