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 (font_h_extents) \
46 HB_FONT_FUNC_IMPLEMENT (font_v_extents) \
47 HB_FONT_FUNC_IMPLEMENT (nominal_glyph) \
48 HB_FONT_FUNC_IMPLEMENT (variation_glyph) \
49 HB_FONT_FUNC_IMPLEMENT (glyph_h_advance) \
50 HB_FONT_FUNC_IMPLEMENT (glyph_v_advance) \
51 HB_FONT_FUNC_IMPLEMENT (glyph_h_origin) \
52 HB_FONT_FUNC_IMPLEMENT (glyph_v_origin) \
53 HB_FONT_FUNC_IMPLEMENT (glyph_h_kerning) \
54 HB_FONT_FUNC_IMPLEMENT (glyph_v_kerning) \
55 HB_FONT_FUNC_IMPLEMENT (glyph_extents) \
56 HB_FONT_FUNC_IMPLEMENT (glyph_contour_point) \
57 HB_FONT_FUNC_IMPLEMENT (glyph_name) \
58 HB_FONT_FUNC_IMPLEMENT (glyph_from_name) \
59 /* ^--- Add new callbacks here */
60
61 struct hb_font_funcs_t {
62 hb_object_header_t header;
63 ASSERT_POD ();
64
65 hb_bool_t immutable;
66
67 struct {
68 #define HB_FONT_FUNC_IMPLEMENT(name) void *name;
69 HB_FONT_FUNCS_IMPLEMENT_CALLBACKS
70 #undef HB_FONT_FUNC_IMPLEMENT
71 } user_data;
72
73 struct {
74 #define HB_FONT_FUNC_IMPLEMENT(name) hb_destroy_func_t name;
75 HB_FONT_FUNCS_IMPLEMENT_CALLBACKS
76 #undef HB_FONT_FUNC_IMPLEMENT
77 } destroy;
78
79 /* Don't access these directly. Call font->get_*() instead. */
80 union get_t {
81 struct get_funcs_t {
82 #define HB_FONT_FUNC_IMPLEMENT(name) hb_font_get_##name##_func_t name;
83 HB_FONT_FUNCS_IMPLEMENT_CALLBACKS
84 #undef HB_FONT_FUNC_IMPLEMENT
85 } f;
86 void (*array[0
87 #define HB_FONT_FUNC_IMPLEMENT(name) +1
88 HB_FONT_FUNCS_IMPLEMENT_CALLBACKS
89 #undef HB_FONT_FUNC_IMPLEMENT
90 ]) (void);
91 } get;
92 };
93
94
95
96 /*
97 * hb_font_t
98 */
99
100 struct hb_font_t {
101 hb_object_header_t header;
102 ASSERT_POD ();
103
104 hb_bool_t immutable;
105
106 hb_font_t *parent;
107 hb_face_t *face;
108
109 int x_scale;
110 int y_scale;
111
112 unsigned int x_ppem;
113 unsigned int y_ppem;
114
115 float ptem;
116
117 /* Font variation coordinates. */
118 unsigned int num_coords;
119 int *coords;
120
121 hb_font_funcs_t *klass;
122 void *user_data;
123 hb_destroy_func_t destroy;
124
125 struct hb_shaper_data_t shaper_data;
126
127
128 /* Convert from font-space to user-space */
129 inline int dir_scale (hb_direction_t direction)
130 { return HB_DIRECTION_IS_VERTICAL(direction) ? y_scale : x_scale; }
131 inline hb_position_t em_scale_x (int16_t v) { return em_scale (v, x_scale); }
132 inline hb_position_t em_scale_y (int16_t v) { return em_scale (v, y_scale); }
133 inline hb_position_t em_scalef_x (float v) { return em_scalef (v, this->x_scale); }
134 inline hb_position_t em_scalef_y (float v) { return em_scalef (v, this->y_scale); }
135 inline float em_fscale_x (int16_t v) { return em_fscale (v, x_scale); }
136 inline float em_fscale_y (int16_t v) { return em_fscale (v, y_scale); }
137 inline hb_position_t em_scale_dir (int16_t v, hb_direction_t direction)
138 { return em_scale (v, dir_scale (direction)); }
139
140 /* Convert from parent-font user-space to our user-space */
141 inline hb_position_t parent_scale_x_distance (hb_position_t v) {
142 if (unlikely (parent && parent->x_scale != x_scale))
143 return (hb_position_t) (v * (int64_t) this->x_scale / this->parent->x_scale);
144 return v;
145 }
146 inline hb_position_t parent_scale_y_distance (hb_position_t v) {
147 if (unlikely (parent && parent->y_scale != y_scale))
148 return (hb_position_t) (v * (int64_t) this->y_scale / this->parent->y_scale);
149 return v;
150 }
151 inline hb_position_t parent_scale_x_position (hb_position_t v) {
152 return parent_scale_x_distance (v);
153 }
154 inline hb_position_t parent_scale_y_position (hb_position_t v) {
155 return parent_scale_y_distance (v);
156 }
157
158 inline void parent_scale_distance (hb_position_t *x, hb_position_t *y) {
159 *x = parent_scale_x_distance (*x);
160 *y = parent_scale_y_distance (*y);
161 }
162 inline void parent_scale_position (hb_position_t *x, hb_position_t *y) {
163 *x = parent_scale_x_position (*x);
164 *y = parent_scale_y_position (*y);
165 }
166
167
168 /* Public getters */
169
170 HB_INTERNAL bool has_func (unsigned int i);
171
172 /* has_* ... */
173 #define HB_FONT_FUNC_IMPLEMENT(name) \
174 bool \
175 has_##name##_func (void) \
176 { \
177 hb_font_funcs_t *funcs = this->klass; \
178 unsigned int i = offsetof (hb_font_funcs_t::get_t::get_funcs_t, name) / sizeof (funcs->get.array[0]); \
179 return has_func (i); \
180 }
181 HB_FONT_FUNCS_IMPLEMENT_CALLBACKS
182 #undef HB_FONT_FUNC_IMPLEMENT
183
184 inline hb_bool_t get_font_h_extents (hb_font_extents_t *extents)
185 {
186 memset (extents, 0, sizeof (*extents));
187 return klass->get.f.font_h_extents (this, user_data,
188 extents,
189 klass->user_data.font_h_extents);
190 }
191 inline hb_bool_t get_font_v_extents (hb_font_extents_t *extents)
192 {
193 memset (extents, 0, sizeof (*extents));
194 return klass->get.f.font_v_extents (this, user_data,
195 extents,
196 klass->user_data.font_v_extents);
197 }
198
199 inline bool has_glyph (hb_codepoint_t unicode)
200 {
201 hb_codepoint_t glyph;
202 return get_nominal_glyph (unicode, &glyph);
203 }
204
205 inline hb_bool_t get_nominal_glyph (hb_codepoint_t unicode,
206 hb_codepoint_t *glyph)
207 {
208 *glyph = 0;
209 return klass->get.f.nominal_glyph (this, user_data,
210 unicode, glyph,
211 klass->user_data.nominal_glyph);
212 }
213
214 inline hb_bool_t get_variation_glyph (hb_codepoint_t unicode, hb_codepoint_t variation_selector,
215 hb_codepoint_t *glyph)
216 {
217 *glyph = 0;
218 return klass->get.f.variation_glyph (this, user_data,
219 unicode, variation_selector, glyph,
220 klass->user_data.variation_glyph);
221 }
222
223 inline hb_position_t get_glyph_h_advance (hb_codepoint_t glyph)
224 {
225 return klass->get.f.glyph_h_advance (this, user_data,
226 glyph,
227 klass->user_data.glyph_h_advance);
228 }
229
230 inline hb_position_t get_glyph_v_advance (hb_codepoint_t glyph)
231 {
232 return klass->get.f.glyph_v_advance (this, user_data,
233 glyph,
234 klass->user_data.glyph_v_advance);
235 }
236
237 inline hb_bool_t get_glyph_h_origin (hb_codepoint_t glyph,
238 hb_position_t *x, hb_position_t *y)
239 {
240 *x = *y = 0;
241 return klass->get.f.glyph_h_origin (this, user_data,
242 glyph, x, y,
243 klass->user_data.glyph_h_origin);
244 }
245
246 inline hb_bool_t get_glyph_v_origin (hb_codepoint_t glyph,
247 hb_position_t *x, hb_position_t *y)
248 {
249 *x = *y = 0;
250 return klass->get.f.glyph_v_origin (this, user_data,
251 glyph, x, y,
252 klass->user_data.glyph_v_origin);
253 }
254
255 inline hb_position_t get_glyph_h_kerning (hb_codepoint_t left_glyph, hb_codepoint_t right_glyph)
256 {
257 return klass->get.f.glyph_h_kerning (this, user_data,
258 left_glyph, right_glyph,
259 klass->user_data.glyph_h_kerning);
260 }
261
262 inline hb_position_t get_glyph_v_kerning (hb_codepoint_t top_glyph, hb_codepoint_t bottom_glyph)
263 {
264 return klass->get.f.glyph_v_kerning (this, user_data,
265 top_glyph, bottom_glyph,
266 klass->user_data.glyph_v_kerning);
267 }
268
269 inline hb_bool_t get_glyph_extents (hb_codepoint_t glyph,
270 hb_glyph_extents_t *extents)
271 {
272 memset (extents, 0, sizeof (*extents));
273 return klass->get.f.glyph_extents (this, user_data,
274 glyph,
275 extents,
276 klass->user_data.glyph_extents);
277 }
278
279 inline hb_bool_t get_glyph_contour_point (hb_codepoint_t glyph, unsigned int point_index,
280 hb_position_t *x, hb_position_t *y)
281 {
282 *x = *y = 0;
283 return klass->get.f.glyph_contour_point (this, user_data,
284 glyph, point_index,
285 x, y,
286 klass->user_data.glyph_contour_point);
287 }
288
289 inline hb_bool_t get_glyph_name (hb_codepoint_t glyph,
290 char *name, unsigned int size)
291 {
292 if (size) *name = '\0';
293 return klass->get.f.glyph_name (this, user_data,
294 glyph,
295 name, size,
296 klass->user_data.glyph_name);
297 }
298
299 inline hb_bool_t get_glyph_from_name (const char *name, int len, /* -1 means nul-terminated */
300 hb_codepoint_t *glyph)
301 {
302 *glyph = 0;
303 if (len == -1) len = strlen (name);
304 return klass->get.f.glyph_from_name (this, user_data,
305 name, len,
306 glyph,
307 klass->user_data.glyph_from_name);
308 }
309
310
311 /* A bit higher-level, and with fallback */
312
313 inline void get_h_extents_with_fallback (hb_font_extents_t *extents)
314 {
315 if (!get_font_h_extents (extents))
316 {
317 extents->ascender = y_scale * .8;
318 extents->descender = extents->ascender - y_scale;
319 extents->line_gap = 0;
320 }
321 }
322 inline void get_v_extents_with_fallback (hb_font_extents_t *extents)
323 {
324 if (!get_font_v_extents (extents))
325 {
326 extents->ascender = x_scale / 2;
327 extents->descender = extents->ascender - x_scale;
328 extents->line_gap = 0;
329 }
330 }
331
332 inline void get_extents_for_direction (hb_direction_t direction,
333 hb_font_extents_t *extents)
334 {
335 if (likely (HB_DIRECTION_IS_HORIZONTAL (direction)))
336 get_h_extents_with_fallback (extents);
337 else
338 get_v_extents_with_fallback (extents);
339 }
340
341 inline void get_glyph_advance_for_direction (hb_codepoint_t glyph,
342 hb_direction_t direction,
343 hb_position_t *x, hb_position_t *y)
344 {
345 if (likely (HB_DIRECTION_IS_HORIZONTAL (direction))) {
346 *x = get_glyph_h_advance (glyph);
347 *y = 0;
348 } else {
349 *x = 0;
350 *y = get_glyph_v_advance (glyph);
351 }
352 }
353
354 inline void guess_v_origin_minus_h_origin (hb_codepoint_t glyph,
355 hb_position_t *x, hb_position_t *y)
356 {
357 *x = get_glyph_h_advance (glyph) / 2;
358
359 /* TODO cache this somehow?! */
360 hb_font_extents_t extents;
361 get_h_extents_with_fallback (&extents);
362 *y = extents.ascender;
363 }
364
365 inline void get_glyph_h_origin_with_fallback (hb_codepoint_t glyph,
366 hb_position_t *x, hb_position_t *y)
367 {
368 if (!get_glyph_h_origin (glyph, x, y) &&
369 get_glyph_v_origin (glyph, x, y))
370 {
371 hb_position_t dx, dy;
372 guess_v_origin_minus_h_origin (glyph, &dx, &dy);
373 *x -= dx; *y -= dy;
374 }
375 }
376 inline void get_glyph_v_origin_with_fallback (hb_codepoint_t glyph,
377 hb_position_t *x, hb_position_t *y)
378 {
379 if (!get_glyph_v_origin (glyph, x, y) &&
380 get_glyph_h_origin (glyph, x, y))
381 {
382 hb_position_t dx, dy;
383 guess_v_origin_minus_h_origin (glyph, &dx, &dy);
384 *x += dx; *y += dy;
385 }
386 }
387
388 inline void get_glyph_origin_for_direction (hb_codepoint_t glyph,
389 hb_direction_t direction,
390 hb_position_t *x, hb_position_t *y)
391 {
392 if (likely (HB_DIRECTION_IS_HORIZONTAL (direction)))
393 get_glyph_h_origin_with_fallback (glyph, x, y);
394 else
395 get_glyph_v_origin_with_fallback (glyph, x, y);
396 }
397
398 inline void add_glyph_h_origin (hb_codepoint_t glyph,
399 hb_position_t *x, hb_position_t *y)
400 {
401 hb_position_t origin_x, origin_y;
402
403 get_glyph_h_origin_with_fallback (glyph, &origin_x, &origin_y);
404
405 *x += origin_x;
406 *y += origin_y;
407 }
408 inline void add_glyph_v_origin (hb_codepoint_t glyph,
409 hb_position_t *x, hb_position_t *y)
410 {
411 hb_position_t origin_x, origin_y;
412
413 get_glyph_v_origin_with_fallback (glyph, &origin_x, &origin_y);
414
415 *x += origin_x;
416 *y += origin_y;
417 }
418 inline void add_glyph_origin_for_direction (hb_codepoint_t glyph,
419 hb_direction_t direction,
420 hb_position_t *x, hb_position_t *y)
421 {
422 hb_position_t origin_x, origin_y;
423
424 get_glyph_origin_for_direction (glyph, direction, &origin_x, &origin_y);
425
426 *x += origin_x;
427 *y += origin_y;
428 }
429
430 inline void subtract_glyph_h_origin (hb_codepoint_t glyph,
431 hb_position_t *x, hb_position_t *y)
432 {
433 hb_position_t origin_x, origin_y;
434
435 get_glyph_h_origin_with_fallback (glyph, &origin_x, &origin_y);
436
437 *x -= origin_x;
438 *y -= origin_y;
439 }
440 inline void subtract_glyph_v_origin (hb_codepoint_t glyph,
441 hb_position_t *x, hb_position_t *y)
442 {
443 hb_position_t origin_x, origin_y;
444
445 get_glyph_v_origin_with_fallback (glyph, &origin_x, &origin_y);
446
447 *x -= origin_x;
448 *y -= origin_y;
449 }
450 inline void subtract_glyph_origin_for_direction (hb_codepoint_t glyph,
451 hb_direction_t direction,
452 hb_position_t *x, hb_position_t *y)
453 {
454 hb_position_t origin_x, origin_y;
455
456 get_glyph_origin_for_direction (glyph, direction, &origin_x, &origin_y);
457
458 *x -= origin_x;
459 *y -= origin_y;
460 }
461
462 inline void get_glyph_kerning_for_direction (hb_codepoint_t first_glyph, hb_codepoint_t second_glyph,
463 hb_direction_t direction,
464 hb_position_t *x, hb_position_t *y)
465 {
466 if (likely (HB_DIRECTION_IS_HORIZONTAL (direction))) {
467 *x = get_glyph_h_kerning (first_glyph, second_glyph);
468 *y = 0;
469 } else {
470 *x = 0;
471 *y = get_glyph_v_kerning (first_glyph, second_glyph);
472 }
473 }
474
475 inline hb_bool_t get_glyph_extents_for_origin (hb_codepoint_t glyph,
476 hb_direction_t direction,
477 hb_glyph_extents_t *extents)
478 {
479 hb_bool_t ret = get_glyph_extents (glyph, extents);
480
481 if (ret)
482 subtract_glyph_origin_for_direction (glyph, direction, &extents->x_bearing, &extents->y_bearing);
483
484 return ret;
485 }
486
487 inline hb_bool_t get_glyph_contour_point_for_origin (hb_codepoint_t glyph, unsigned int point_index,
488 hb_direction_t direction,
489 hb_position_t *x, hb_position_t *y)
490 {
491 hb_bool_t ret = get_glyph_contour_point (glyph, point_index, x, y);
492
493 if (ret)
494 subtract_glyph_origin_for_direction (glyph, direction, x, y);
495
496 return ret;
497 }
498
499 /* Generates gidDDD if glyph has no name. */
500 inline void
501 glyph_to_string (hb_codepoint_t glyph,
502 char *s, unsigned int size)
503 {
504 if (get_glyph_name (glyph, s, size)) return;
505
506 if (size && snprintf (s, size, "gid%u", glyph) < 0)
507 *s = '\0';
508 }
509
510 /* Parses gidDDD and uniUUUU strings automatically. */
511 inline hb_bool_t
512 glyph_from_string (const char *s, int len, /* -1 means nul-terminated */
513 hb_codepoint_t *glyph)
514 {
515 if (get_glyph_from_name (s, len, glyph)) return true;
516
517 if (len == -1) len = strlen (s);
518
519 /* Straight glyph index. */
520 if (hb_codepoint_parse (s, len, 10, glyph))
521 return true;
522
523 if (len > 3)
524 {
525 /* gidDDD syntax for glyph indices. */
526 if (0 == strncmp (s, "gid", 3) &&
527 hb_codepoint_parse (s + 3, len - 3, 10, glyph))
528 return true;
529
530 /* uniUUUU and other Unicode character indices. */
531 hb_codepoint_t unichar;
532 if (0 == strncmp (s, "uni", 3) &&
533 hb_codepoint_parse (s + 3, len - 3, 16, &unichar) &&
534 get_nominal_glyph (unichar, glyph))
535 return true;
536 }
537
538 return false;
539 }
540
541 inline hb_position_t em_scale (int16_t v, int scale)
542 {
543 int upem = face->get_upem ();
544 int64_t scaled = v * (int64_t) scale;
545 scaled += scaled >= 0 ? upem/2 : -upem/2; /* Round. */
546 return (hb_position_t) (scaled / upem);
547 }
548 inline hb_position_t em_scalef (float v, int scale)
549 {
550 return (hb_position_t) round (v * scale / face->get_upem ());
551 }
552 inline float em_fscale (int16_t v, int scale)
553 {
554 return (float) v * scale / face->get_upem ();
555 }
556 };
557
558 #define HB_SHAPER_DATA_CREATE_FUNC_EXTRA_ARGS
559 #define HB_SHAPER_IMPLEMENT(shaper) HB_SHAPER_DATA_PROTOTYPE(shaper, font);
560 #include "hb-shaper-list.hh"
561 #undef HB_SHAPER_IMPLEMENT
562 #undef HB_SHAPER_DATA_CREATE_FUNC_EXTRA_ARGS
563
564
565 #endif /* HB_FONT_PRIVATE_HH */