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_HH
30#define HB_FONT_HH
31
32#include "hb.hh"
33
34#include "hb-face.hh"
35#include "hb-shaper.hh"
36
37
38/*
39 * hb_font_funcs_t
40 */
41
42#define HB_FONT_FUNCS_IMPLEMENT_CALLBACKS \
43 HB_FONT_FUNC_IMPLEMENT (font_h_extents) \
44 HB_FONT_FUNC_IMPLEMENT (font_v_extents) \
45 HB_FONT_FUNC_IMPLEMENT (nominal_glyph) \
46 HB_FONT_FUNC_IMPLEMENT (nominal_glyphs) \
47 HB_FONT_FUNC_IMPLEMENT (variation_glyph) \
48 HB_FONT_FUNC_IMPLEMENT (glyph_h_advance) \
49 HB_FONT_FUNC_IMPLEMENT (glyph_v_advance) \
50 HB_FONT_FUNC_IMPLEMENT (glyph_h_advances) \
51 HB_FONT_FUNC_IMPLEMENT (glyph_v_advances) \
52 HB_FONT_FUNC_IMPLEMENT (glyph_h_origin) \
53 HB_FONT_FUNC_IMPLEMENT (glyph_v_origin) \
54 HB_FONT_FUNC_IMPLEMENT (glyph_h_kerning) \
55 HB_IF_NOT_DEPRECATED (HB_FONT_FUNC_IMPLEMENT (glyph_v_kerning)) \
56 HB_FONT_FUNC_IMPLEMENT (glyph_extents) \
57 HB_FONT_FUNC_IMPLEMENT (glyph_contour_point) \
58 HB_FONT_FUNC_IMPLEMENT (glyph_name) \
59 HB_FONT_FUNC_IMPLEMENT (glyph_from_name) \
60 /* ^--- Add new callbacks here */
61
62struct hb_font_funcs_t
63{
64 hb_object_header_t header;
65
66 struct {
67#define HB_FONT_FUNC_IMPLEMENT(name) void *name;
68 HB_FONT_FUNCS_IMPLEMENT_CALLBACKS
69#undef HB_FONT_FUNC_IMPLEMENT
70 } user_data;
71
72 struct {
73#define HB_FONT_FUNC_IMPLEMENT(name) hb_destroy_func_t name;
74 HB_FONT_FUNCS_IMPLEMENT_CALLBACKS
75#undef HB_FONT_FUNC_IMPLEMENT
76 } destroy;
77
78 /* Don't access these directly. Call font->get_*() instead. */
79 union get_t {
80 struct get_funcs_t {
81#define HB_FONT_FUNC_IMPLEMENT(name) hb_font_get_##name##_func_t name;
82 HB_FONT_FUNCS_IMPLEMENT_CALLBACKS
83#undef HB_FONT_FUNC_IMPLEMENT
84 } f;
85 void (*array[0
86#define HB_FONT_FUNC_IMPLEMENT(name) +1
87 HB_FONT_FUNCS_IMPLEMENT_CALLBACKS
88#undef HB_FONT_FUNC_IMPLEMENT
89 ]) ();
90 } get;
91};
92DECLARE_NULL_INSTANCE (hb_font_funcs_t);
93
94
95/*
96 * hb_font_t
97 */
98
99#define HB_SHAPER_IMPLEMENT(shaper) HB_SHAPER_DATA_INSTANTIATE_SHAPERS(shaper, font);
100#include "hb-shaper-list.hh"
101#undef HB_SHAPER_IMPLEMENT
102
103struct hb_font_t
104{
105 hb_object_header_t header;
106
107 hb_font_t *parent;
108 hb_face_t *face;
109
110 int32_t x_scale;
111 int32_t y_scale;
112 int64_t x_mult;
113 int64_t y_mult;
114
115 unsigned int x_ppem;
116 unsigned int y_ppem;
117
118 float ptem;
119
120 /* Font variation coordinates. */
121 unsigned int num_coords;
122 int *coords;
123
124 hb_font_funcs_t *klass;
125 void *user_data;
126 hb_destroy_func_t destroy;
127
128 hb_shaper_object_dataset_t<hb_font_t> data; /* Various shaper data. */
129
130
131 /* Convert from font-space to user-space */
132 int64_t dir_mult (hb_direction_t direction)
133 { return HB_DIRECTION_IS_VERTICAL(direction) ? y_mult : x_mult; }
134 hb_position_t em_scale_x (int16_t v) { return em_mult (v, x_mult); }
135 hb_position_t em_scale_y (int16_t v) { return em_mult (v, y_mult); }
136 hb_position_t em_scalef_x (float v) { return em_scalef (v, x_scale); }
137 hb_position_t em_scalef_y (float v) { return em_scalef (v, y_scale); }
138 float em_fscale_x (int16_t v) { return em_fscale (v, x_scale); }
139 float em_fscale_y (int16_t v) { return em_fscale (v, y_scale); }
140 hb_position_t em_scale_dir (int16_t v, hb_direction_t direction)
141 { return em_mult (v, dir_mult (direction)); }
142
143 /* Convert from parent-font user-space to our user-space */
144 hb_position_t parent_scale_x_distance (hb_position_t v)
145 {
146 if (unlikely (parent && parent->x_scale != x_scale))
147 return (hb_position_t) (v * (int64_t) this->x_scale / this->parent->x_scale);
148 return v;
149 }
150 hb_position_t parent_scale_y_distance (hb_position_t v)
151 {
152 if (unlikely (parent && parent->y_scale != y_scale))
153 return (hb_position_t) (v * (int64_t) this->y_scale / this->parent->y_scale);
154 return v;
155 }
156 hb_position_t parent_scale_x_position (hb_position_t v)
157 { return parent_scale_x_distance (v); }
158 hb_position_t parent_scale_y_position (hb_position_t v)
159 { return parent_scale_y_distance (v); }
160
161 void parent_scale_distance (hb_position_t *x, hb_position_t *y)
162 {
163 *x = parent_scale_x_distance (*x);
164 *y = parent_scale_y_distance (*y);
165 }
166 void parent_scale_position (hb_position_t *x, hb_position_t *y)
167 {
168 *x = parent_scale_x_position (*x);
169 *y = parent_scale_y_position (*y);
170 }
171
172
173 /* Public getters */
174
175 HB_INTERNAL bool has_func (unsigned int i);
176 HB_INTERNAL bool has_func_set (unsigned int i);
177
178 /* has_* ... */
179#define HB_FONT_FUNC_IMPLEMENT(name) \
180 bool \
181 has_##name##_func () \
182 { \
183 hb_font_funcs_t *funcs = this->klass; \
184 unsigned int i = offsetof (hb_font_funcs_t::get_t::get_funcs_t, name) / sizeof (funcs->get.array[0]); \
185 return has_func (i); \
186 } \
187 bool \
188 has_##name##_func_set () \
189 { \
190 hb_font_funcs_t *funcs = this->klass; \
191 unsigned int i = offsetof (hb_font_funcs_t::get_t::get_funcs_t, name) / sizeof (funcs->get.array[0]); \
192 return has_func_set (i); \
193 }
194 HB_FONT_FUNCS_IMPLEMENT_CALLBACKS
195#undef HB_FONT_FUNC_IMPLEMENT
196
197 hb_bool_t get_font_h_extents (hb_font_extents_t *extents)
198 {
199 memset (extents, 0, sizeof (*extents));
200 return klass->get.f.font_h_extents (this, user_data,
201 extents,
202 klass->user_data.font_h_extents);
203 }
204 hb_bool_t get_font_v_extents (hb_font_extents_t *extents)
205 {
206 memset (extents, 0, sizeof (*extents));
207 return klass->get.f.font_v_extents (this, user_data,
208 extents,
209 klass->user_data.font_v_extents);
210 }
211
212 bool has_glyph (hb_codepoint_t unicode)
213 {
214 hb_codepoint_t glyph;
215 return get_nominal_glyph (unicode, &glyph);
216 }
217
218 hb_bool_t get_nominal_glyph (hb_codepoint_t unicode,
219 hb_codepoint_t *glyph)
220 {
221 *glyph = 0;
222 return klass->get.f.nominal_glyph (this, user_data,
223 unicode, glyph,
224 klass->user_data.nominal_glyph);
225 }
226 unsigned int get_nominal_glyphs (unsigned int count,
227 const hb_codepoint_t *first_unicode,
228 unsigned int unicode_stride,
229 hb_codepoint_t *first_glyph,
230 unsigned int glyph_stride)
231 {
232 return klass->get.f.nominal_glyphs (this, user_data,
233 count,
234 first_unicode, unicode_stride,
235 first_glyph, glyph_stride,
236 klass->user_data.nominal_glyphs);
237 }
238
239 hb_bool_t get_variation_glyph (hb_codepoint_t unicode, hb_codepoint_t variation_selector,
240 hb_codepoint_t *glyph)
241 {
242 *glyph = 0;
243 return klass->get.f.variation_glyph (this, user_data,
244 unicode, variation_selector, glyph,
245 klass->user_data.variation_glyph);
246 }
247
248 hb_position_t get_glyph_h_advance (hb_codepoint_t glyph)
249 {
250 return klass->get.f.glyph_h_advance (this, user_data,
251 glyph,
252 klass->user_data.glyph_h_advance);
253 }
254
255 hb_position_t get_glyph_v_advance (hb_codepoint_t glyph)
256 {
257 return klass->get.f.glyph_v_advance (this, user_data,
258 glyph,
259 klass->user_data.glyph_v_advance);
260 }
261
262 void get_glyph_h_advances (unsigned int count,
263 const hb_codepoint_t *first_glyph,
264 unsigned int glyph_stride,
265 hb_position_t *first_advance,
266 unsigned int advance_stride)
267 {
268 return klass->get.f.glyph_h_advances (this, user_data,
269 count,
270 first_glyph, glyph_stride,
271 first_advance, advance_stride,
272 klass->user_data.glyph_h_advances);
273 }
274
275 void get_glyph_v_advances (unsigned int count,
276 const hb_codepoint_t *first_glyph,
277 unsigned int glyph_stride,
278 hb_position_t *first_advance,
279 unsigned int advance_stride)
280 {
281 return klass->get.f.glyph_v_advances (this, user_data,
282 count,
283 first_glyph, glyph_stride,
284 first_advance, advance_stride,
285 klass->user_data.glyph_v_advances);
286 }
287
288 hb_bool_t get_glyph_h_origin (hb_codepoint_t glyph,
289 hb_position_t *x, hb_position_t *y)
290 {
291 *x = *y = 0;
292 return klass->get.f.glyph_h_origin (this, user_data,
293 glyph, x, y,
294 klass->user_data.glyph_h_origin);
295 }
296
297 hb_bool_t get_glyph_v_origin (hb_codepoint_t glyph,
298 hb_position_t *x, hb_position_t *y)
299 {
300 *x = *y = 0;
301 return klass->get.f.glyph_v_origin (this, user_data,
302 glyph, x, y,
303 klass->user_data.glyph_v_origin);
304 }
305
306 hb_position_t get_glyph_h_kerning (hb_codepoint_t left_glyph,
307 hb_codepoint_t right_glyph)
308 {
309#ifdef HB_DISABLE_DEPRECATED
310 return 0;
311#else
312 return klass->get.f.glyph_h_kerning (this, user_data,
313 left_glyph, right_glyph,
314 klass->user_data.glyph_h_kerning);
315#endif
316 }
317
318 hb_position_t get_glyph_v_kerning (hb_codepoint_t top_glyph,
319 hb_codepoint_t bottom_glyph)
320 {
321#ifdef HB_DISABLE_DEPRECATED
322 return 0;
323#else
324 return klass->get.f.glyph_v_kerning (this, user_data,
325 top_glyph, bottom_glyph,
326 klass->user_data.glyph_v_kerning);
327#endif
328 }
329
330 hb_bool_t get_glyph_extents (hb_codepoint_t glyph,
331 hb_glyph_extents_t *extents)
332 {
333 memset (extents, 0, sizeof (*extents));
334 return klass->get.f.glyph_extents (this, user_data,
335 glyph,
336 extents,
337 klass->user_data.glyph_extents);
338 }
339
340 hb_bool_t get_glyph_contour_point (hb_codepoint_t glyph, unsigned int point_index,
341 hb_position_t *x, hb_position_t *y)
342 {
343 *x = *y = 0;
344 return klass->get.f.glyph_contour_point (this, user_data,
345 glyph, point_index,
346 x, y,
347 klass->user_data.glyph_contour_point);
348 }
349
350 hb_bool_t get_glyph_name (hb_codepoint_t glyph,
351 char *name, unsigned int size)
352 {
353 if (size) *name = '\0';
354 return klass->get.f.glyph_name (this, user_data,
355 glyph,
356 name, size,
357 klass->user_data.glyph_name);
358 }
359
360 hb_bool_t get_glyph_from_name (const char *name, int len, /* -1 means nul-terminated */
361 hb_codepoint_t *glyph)
362 {
363 *glyph = 0;
364 if (len == -1) len = strlen (name);
365 return klass->get.f.glyph_from_name (this, user_data,
366 name, len,
367 glyph,
368 klass->user_data.glyph_from_name);
369 }
370
371
372 /* A bit higher-level, and with fallback */
373
374 void get_h_extents_with_fallback (hb_font_extents_t *extents)
375 {
376 if (!get_font_h_extents (extents))
377 {
378 extents->ascender = y_scale * .8;
379 extents->descender = extents->ascender - y_scale;
380 extents->line_gap = 0;
381 }
382 }
383 void get_v_extents_with_fallback (hb_font_extents_t *extents)
384 {
385 if (!get_font_v_extents (extents))
386 {
387 extents->ascender = x_scale / 2;
388 extents->descender = extents->ascender - x_scale;
389 extents->line_gap = 0;
390 }
391 }
392
393 void get_extents_for_direction (hb_direction_t direction,
394 hb_font_extents_t *extents)
395 {
396 if (likely (HB_DIRECTION_IS_HORIZONTAL (direction)))
397 get_h_extents_with_fallback (extents);
398 else
399 get_v_extents_with_fallback (extents);
400 }
401
402 void get_glyph_advance_for_direction (hb_codepoint_t glyph,
403 hb_direction_t direction,
404 hb_position_t *x, hb_position_t *y)
405 {
406 *x = *y = 0;
407 if (likely (HB_DIRECTION_IS_HORIZONTAL (direction)))
408 *x = get_glyph_h_advance (glyph);
409 else
410 *y = get_glyph_v_advance (glyph);
411 }
412 void get_glyph_advances_for_direction (hb_direction_t direction,
413 unsigned int count,
414 const hb_codepoint_t *first_glyph,
415 unsigned glyph_stride,
416 hb_position_t *first_advance,
417 unsigned advance_stride)
418 {
419 if (likely (HB_DIRECTION_IS_HORIZONTAL (direction)))
420 get_glyph_h_advances (count, first_glyph, glyph_stride, first_advance, advance_stride);
421 else
422 get_glyph_v_advances (count, first_glyph, glyph_stride, first_advance, advance_stride);
423 }
424
425 void guess_v_origin_minus_h_origin (hb_codepoint_t glyph,
426 hb_position_t *x, hb_position_t *y)
427 {
428 *x = get_glyph_h_advance (glyph) / 2;
429
430 /* TODO cache this somehow?! */
431 hb_font_extents_t extents;
432 get_h_extents_with_fallback (&extents);
433 *y = extents.ascender;
434 }
435
436 void get_glyph_h_origin_with_fallback (hb_codepoint_t glyph,
437 hb_position_t *x, hb_position_t *y)
438 {
439 if (!get_glyph_h_origin (glyph, x, y) &&
440 get_glyph_v_origin (glyph, x, y))
441 {
442 hb_position_t dx, dy;
443 guess_v_origin_minus_h_origin (glyph, &dx, &dy);
444 *x -= dx; *y -= dy;
445 }
446 }
447 void get_glyph_v_origin_with_fallback (hb_codepoint_t glyph,
448 hb_position_t *x, hb_position_t *y)
449 {
450 if (!get_glyph_v_origin (glyph, x, y) &&
451 get_glyph_h_origin (glyph, x, y))
452 {
453 hb_position_t dx, dy;
454 guess_v_origin_minus_h_origin (glyph, &dx, &dy);
455 *x += dx; *y += dy;
456 }
457 }
458
459 void get_glyph_origin_for_direction (hb_codepoint_t glyph,
460 hb_direction_t direction,
461 hb_position_t *x, hb_position_t *y)
462 {
463 if (likely (HB_DIRECTION_IS_HORIZONTAL (direction)))
464 get_glyph_h_origin_with_fallback (glyph, x, y);
465 else
466 get_glyph_v_origin_with_fallback (glyph, x, y);
467 }
468
469 void add_glyph_h_origin (hb_codepoint_t glyph,
470 hb_position_t *x, hb_position_t *y)
471 {
472 hb_position_t origin_x, origin_y;
473
474 get_glyph_h_origin_with_fallback (glyph, &origin_x, &origin_y);
475
476 *x += origin_x;
477 *y += origin_y;
478 }
479 void add_glyph_v_origin (hb_codepoint_t glyph,
480 hb_position_t *x, hb_position_t *y)
481 {
482 hb_position_t origin_x, origin_y;
483
484 get_glyph_v_origin_with_fallback (glyph, &origin_x, &origin_y);
485
486 *x += origin_x;
487 *y += origin_y;
488 }
489 void add_glyph_origin_for_direction (hb_codepoint_t glyph,
490 hb_direction_t direction,
491 hb_position_t *x, hb_position_t *y)
492 {
493 hb_position_t origin_x, origin_y;
494
495 get_glyph_origin_for_direction (glyph, direction, &origin_x, &origin_y);
496
497 *x += origin_x;
498 *y += origin_y;
499 }
500
501 void subtract_glyph_h_origin (hb_codepoint_t glyph,
502 hb_position_t *x, hb_position_t *y)
503 {
504 hb_position_t origin_x, origin_y;
505
506 get_glyph_h_origin_with_fallback (glyph, &origin_x, &origin_y);
507
508 *x -= origin_x;
509 *y -= origin_y;
510 }
511 void subtract_glyph_v_origin (hb_codepoint_t glyph,
512 hb_position_t *x, hb_position_t *y)
513 {
514 hb_position_t origin_x, origin_y;
515
516 get_glyph_v_origin_with_fallback (glyph, &origin_x, &origin_y);
517
518 *x -= origin_x;
519 *y -= origin_y;
520 }
521 void subtract_glyph_origin_for_direction (hb_codepoint_t glyph,
522 hb_direction_t direction,
523 hb_position_t *x, hb_position_t *y)
524 {
525 hb_position_t origin_x, origin_y;
526
527 get_glyph_origin_for_direction (glyph, direction, &origin_x, &origin_y);
528
529 *x -= origin_x;
530 *y -= origin_y;
531 }
532
533 void get_glyph_kerning_for_direction (hb_codepoint_t first_glyph, hb_codepoint_t second_glyph,
534 hb_direction_t direction,
535 hb_position_t *x, hb_position_t *y)
536 {
537 if (likely (HB_DIRECTION_IS_HORIZONTAL (direction))) {
538 *y = 0;
539 *x = get_glyph_h_kerning (first_glyph, second_glyph);
540 } else {
541 *x = 0;
542 *y = get_glyph_v_kerning (first_glyph, second_glyph);
543 }
544 }
545
546 hb_bool_t get_glyph_extents_for_origin (hb_codepoint_t glyph,
547 hb_direction_t direction,
548 hb_glyph_extents_t *extents)
549 {
550 hb_bool_t ret = get_glyph_extents (glyph, extents);
551
552 if (ret)
553 subtract_glyph_origin_for_direction (glyph, direction, &extents->x_bearing, &extents->y_bearing);
554
555 return ret;
556 }
557
558 hb_bool_t get_glyph_contour_point_for_origin (hb_codepoint_t glyph, unsigned int point_index,
559 hb_direction_t direction,
560 hb_position_t *x, hb_position_t *y)
561 {
562 hb_bool_t ret = get_glyph_contour_point (glyph, point_index, x, y);
563
564 if (ret)
565 subtract_glyph_origin_for_direction (glyph, direction, x, y);
566
567 return ret;
568 }
569
570 /* Generates gidDDD if glyph has no name. */
571 void
572 glyph_to_string (hb_codepoint_t glyph,
573 char *s, unsigned int size)
574 {
575 if (get_glyph_name (glyph, s, size)) return;
576
577 if (size && snprintf (s, size, "gid%u", glyph) < 0)
578 *s = '\0';
579 }
580
581 /* Parses gidDDD and uniUUUU strings automatically. */
582 hb_bool_t
583 glyph_from_string (const char *s, int len, /* -1 means nul-terminated */
584 hb_codepoint_t *glyph)
585 {
586 if (get_glyph_from_name (s, len, glyph)) return true;
587
588 if (len == -1) len = strlen (s);
589
590 /* Straight glyph index. */
591 if (hb_codepoint_parse (s, len, 10, glyph))
592 return true;
593
594 if (len > 3)
595 {
596 /* gidDDD syntax for glyph indices. */
597 if (0 == strncmp (s, "gid", 3) &&
598 hb_codepoint_parse (s + 3, len - 3, 10, glyph))
599 return true;
600
601 /* uniUUUU and other Unicode character indices. */
602 hb_codepoint_t unichar;
603 if (0 == strncmp (s, "uni", 3) &&
604 hb_codepoint_parse (s + 3, len - 3, 16, &unichar) &&
605 get_nominal_glyph (unichar, glyph))
606 return true;
607 }
608
609 return false;
610 }
611
612 void mults_changed ()
613 {
614 signed upem = face->get_upem ();
615 x_mult = ((int64_t) x_scale << 16) / upem;
616 y_mult = ((int64_t) y_scale << 16) / upem;
617 }
618
619 hb_position_t em_mult (int16_t v, int64_t mult)
620 {
621 return (hb_position_t) ((v * mult) >> 16);
622 }
623 hb_position_t em_scalef (float v, int scale)
624 { return (hb_position_t) roundf (v * scale / face->get_upem ()); }
625 float em_fscale (int16_t v, int scale)
626 { return (float) v * scale / face->get_upem (); }
627};
628DECLARE_NULL_INSTANCE (hb_font_t);
629
630
631#endif /* HB_FONT_HH */
632