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 float *design_coords;
124
125 hb_font_funcs_t *klass;
126 void *user_data;
127 hb_destroy_func_t destroy;
128
129 hb_shaper_object_dataset_t<hb_font_t> data; /* Various shaper data. */
130
131
132 /* Convert from font-space to user-space */
133 int64_t dir_mult (hb_direction_t direction)
134 { return HB_DIRECTION_IS_VERTICAL(direction) ? y_mult : x_mult; }
135 hb_position_t em_scale_x (int16_t v) { return em_mult (v, x_mult); }
136 hb_position_t em_scale_y (int16_t v) { return em_mult (v, y_mult); }
137 hb_position_t em_scalef_x (float v) { return em_scalef (v, x_scale); }
138 hb_position_t em_scalef_y (float v) { return em_scalef (v, y_scale); }
139 float em_fscale_x (int16_t v) { return em_fscale (v, x_scale); }
140 float em_fscale_y (int16_t v) { return em_fscale (v, y_scale); }
141 hb_position_t em_scale_dir (int16_t v, hb_direction_t direction)
142 { return em_mult (v, dir_mult (direction)); }
143
144 /* Convert from parent-font user-space to our user-space */
145 hb_position_t parent_scale_x_distance (hb_position_t v)
146 {
147 if (unlikely (parent && parent->x_scale != x_scale))
148 return (hb_position_t) (v * (int64_t) this->x_scale / this->parent->x_scale);
149 return v;
150 }
151 hb_position_t parent_scale_y_distance (hb_position_t v)
152 {
153 if (unlikely (parent && parent->y_scale != y_scale))
154 return (hb_position_t) (v * (int64_t) this->y_scale / this->parent->y_scale);
155 return v;
156 }
157 hb_position_t parent_scale_x_position (hb_position_t v)
158 { return parent_scale_x_distance (v); }
159 hb_position_t parent_scale_y_position (hb_position_t v)
160 { return parent_scale_y_distance (v); }
161
162 void parent_scale_distance (hb_position_t *x, hb_position_t *y)
163 {
164 *x = parent_scale_x_distance (*x);
165 *y = parent_scale_y_distance (*y);
166 }
167 void parent_scale_position (hb_position_t *x, hb_position_t *y)
168 {
169 *x = parent_scale_x_position (*x);
170 *y = parent_scale_y_position (*y);
171 }
172
173
174 /* Public getters */
175
176 HB_INTERNAL bool has_func (unsigned int i);
177 HB_INTERNAL bool has_func_set (unsigned int i);
178
179 /* has_* ... */
180#define HB_FONT_FUNC_IMPLEMENT(name) \
181 bool \
182 has_##name##_func () \
183 { \
184 hb_font_funcs_t *funcs = this->klass; \
185 unsigned int i = offsetof (hb_font_funcs_t::get_t::get_funcs_t, name) / sizeof (funcs->get.array[0]); \
186 return has_func (i); \
187 } \
188 bool \
189 has_##name##_func_set () \
190 { \
191 hb_font_funcs_t *funcs = this->klass; \
192 unsigned int i = offsetof (hb_font_funcs_t::get_t::get_funcs_t, name) / sizeof (funcs->get.array[0]); \
193 return has_func_set (i); \
194 }
195 HB_FONT_FUNCS_IMPLEMENT_CALLBACKS
196#undef HB_FONT_FUNC_IMPLEMENT
197
198 hb_bool_t get_font_h_extents (hb_font_extents_t *extents)
199 {
200 memset (extents, 0, sizeof (*extents));
201 return klass->get.f.font_h_extents (this, user_data,
202 extents,
203 klass->user_data.font_h_extents);
204 }
205 hb_bool_t get_font_v_extents (hb_font_extents_t *extents)
206 {
207 memset (extents, 0, sizeof (*extents));
208 return klass->get.f.font_v_extents (this, user_data,
209 extents,
210 klass->user_data.font_v_extents);
211 }
212
213 bool has_glyph (hb_codepoint_t unicode)
214 {
215 hb_codepoint_t glyph;
216 return get_nominal_glyph (unicode, &glyph);
217 }
218
219 hb_bool_t get_nominal_glyph (hb_codepoint_t unicode,
220 hb_codepoint_t *glyph)
221 {
222 *glyph = 0;
223 return klass->get.f.nominal_glyph (this, user_data,
224 unicode, glyph,
225 klass->user_data.nominal_glyph);
226 }
227 unsigned int get_nominal_glyphs (unsigned int count,
228 const hb_codepoint_t *first_unicode,
229 unsigned int unicode_stride,
230 hb_codepoint_t *first_glyph,
231 unsigned int glyph_stride)
232 {
233 return klass->get.f.nominal_glyphs (this, user_data,
234 count,
235 first_unicode, unicode_stride,
236 first_glyph, glyph_stride,
237 klass->user_data.nominal_glyphs);
238 }
239
240 hb_bool_t get_variation_glyph (hb_codepoint_t unicode, hb_codepoint_t variation_selector,
241 hb_codepoint_t *glyph)
242 {
243 *glyph = 0;
244 return klass->get.f.variation_glyph (this, user_data,
245 unicode, variation_selector, glyph,
246 klass->user_data.variation_glyph);
247 }
248
249 hb_position_t get_glyph_h_advance (hb_codepoint_t glyph)
250 {
251 return klass->get.f.glyph_h_advance (this, user_data,
252 glyph,
253 klass->user_data.glyph_h_advance);
254 }
255
256 hb_position_t get_glyph_v_advance (hb_codepoint_t glyph)
257 {
258 return klass->get.f.glyph_v_advance (this, user_data,
259 glyph,
260 klass->user_data.glyph_v_advance);
261 }
262
263 void get_glyph_h_advances (unsigned int count,
264 const hb_codepoint_t *first_glyph,
265 unsigned int glyph_stride,
266 hb_position_t *first_advance,
267 unsigned int advance_stride)
268 {
269 return klass->get.f.glyph_h_advances (this, user_data,
270 count,
271 first_glyph, glyph_stride,
272 first_advance, advance_stride,
273 klass->user_data.glyph_h_advances);
274 }
275
276 void get_glyph_v_advances (unsigned int count,
277 const hb_codepoint_t *first_glyph,
278 unsigned int glyph_stride,
279 hb_position_t *first_advance,
280 unsigned int advance_stride)
281 {
282 return klass->get.f.glyph_v_advances (this, user_data,
283 count,
284 first_glyph, glyph_stride,
285 first_advance, advance_stride,
286 klass->user_data.glyph_v_advances);
287 }
288
289 hb_bool_t get_glyph_h_origin (hb_codepoint_t glyph,
290 hb_position_t *x, hb_position_t *y)
291 {
292 *x = *y = 0;
293 return klass->get.f.glyph_h_origin (this, user_data,
294 glyph, x, y,
295 klass->user_data.glyph_h_origin);
296 }
297
298 hb_bool_t get_glyph_v_origin (hb_codepoint_t glyph,
299 hb_position_t *x, hb_position_t *y)
300 {
301 *x = *y = 0;
302 return klass->get.f.glyph_v_origin (this, user_data,
303 glyph, x, y,
304 klass->user_data.glyph_v_origin);
305 }
306
307 hb_position_t get_glyph_h_kerning (hb_codepoint_t left_glyph,
308 hb_codepoint_t right_glyph)
309 {
310#ifdef HB_DISABLE_DEPRECATED
311 return 0;
312#else
313 return klass->get.f.glyph_h_kerning (this, user_data,
314 left_glyph, right_glyph,
315 klass->user_data.glyph_h_kerning);
316#endif
317 }
318
319 hb_position_t get_glyph_v_kerning (hb_codepoint_t top_glyph,
320 hb_codepoint_t bottom_glyph)
321 {
322#ifdef HB_DISABLE_DEPRECATED
323 return 0;
324#else
325 return klass->get.f.glyph_v_kerning (this, user_data,
326 top_glyph, bottom_glyph,
327 klass->user_data.glyph_v_kerning);
328#endif
329 }
330
331 hb_bool_t get_glyph_extents (hb_codepoint_t glyph,
332 hb_glyph_extents_t *extents)
333 {
334 memset (extents, 0, sizeof (*extents));
335 return klass->get.f.glyph_extents (this, user_data,
336 glyph,
337 extents,
338 klass->user_data.glyph_extents);
339 }
340
341 hb_bool_t get_glyph_contour_point (hb_codepoint_t glyph, unsigned int point_index,
342 hb_position_t *x, hb_position_t *y)
343 {
344 *x = *y = 0;
345 return klass->get.f.glyph_contour_point (this, user_data,
346 glyph, point_index,
347 x, y,
348 klass->user_data.glyph_contour_point);
349 }
350
351 hb_bool_t get_glyph_name (hb_codepoint_t glyph,
352 char *name, unsigned int size)
353 {
354 if (size) *name = '\0';
355 return klass->get.f.glyph_name (this, user_data,
356 glyph,
357 name, size,
358 klass->user_data.glyph_name);
359 }
360
361 hb_bool_t get_glyph_from_name (const char *name, int len, /* -1 means nul-terminated */
362 hb_codepoint_t *glyph)
363 {
364 *glyph = 0;
365 if (len == -1) len = strlen (name);
366 return klass->get.f.glyph_from_name (this, user_data,
367 name, len,
368 glyph,
369 klass->user_data.glyph_from_name);
370 }
371
372
373 /* A bit higher-level, and with fallback */
374
375 void get_h_extents_with_fallback (hb_font_extents_t *extents)
376 {
377 if (!get_font_h_extents (extents))
378 {
379 extents->ascender = y_scale * .8;
380 extents->descender = extents->ascender - y_scale;
381 extents->line_gap = 0;
382 }
383 }
384 void get_v_extents_with_fallback (hb_font_extents_t *extents)
385 {
386 if (!get_font_v_extents (extents))
387 {
388 extents->ascender = x_scale / 2;
389 extents->descender = extents->ascender - x_scale;
390 extents->line_gap = 0;
391 }
392 }
393
394 void get_extents_for_direction (hb_direction_t direction,
395 hb_font_extents_t *extents)
396 {
397 if (likely (HB_DIRECTION_IS_HORIZONTAL (direction)))
398 get_h_extents_with_fallback (extents);
399 else
400 get_v_extents_with_fallback (extents);
401 }
402
403 void get_glyph_advance_for_direction (hb_codepoint_t glyph,
404 hb_direction_t direction,
405 hb_position_t *x, hb_position_t *y)
406 {
407 *x = *y = 0;
408 if (likely (HB_DIRECTION_IS_HORIZONTAL (direction)))
409 *x = get_glyph_h_advance (glyph);
410 else
411 *y = get_glyph_v_advance (glyph);
412 }
413 void get_glyph_advances_for_direction (hb_direction_t direction,
414 unsigned int count,
415 const hb_codepoint_t *first_glyph,
416 unsigned glyph_stride,
417 hb_position_t *first_advance,
418 unsigned advance_stride)
419 {
420 if (likely (HB_DIRECTION_IS_HORIZONTAL (direction)))
421 get_glyph_h_advances (count, first_glyph, glyph_stride, first_advance, advance_stride);
422 else
423 get_glyph_v_advances (count, first_glyph, glyph_stride, first_advance, advance_stride);
424 }
425
426 void guess_v_origin_minus_h_origin (hb_codepoint_t glyph,
427 hb_position_t *x, hb_position_t *y)
428 {
429 *x = get_glyph_h_advance (glyph) / 2;
430
431 /* TODO cache this somehow?! */
432 hb_font_extents_t extents;
433 get_h_extents_with_fallback (&extents);
434 *y = extents.ascender;
435 }
436
437 void get_glyph_h_origin_with_fallback (hb_codepoint_t glyph,
438 hb_position_t *x, hb_position_t *y)
439 {
440 if (!get_glyph_h_origin (glyph, x, y) &&
441 get_glyph_v_origin (glyph, x, y))
442 {
443 hb_position_t dx, dy;
444 guess_v_origin_minus_h_origin (glyph, &dx, &dy);
445 *x -= dx; *y -= dy;
446 }
447 }
448 void get_glyph_v_origin_with_fallback (hb_codepoint_t glyph,
449 hb_position_t *x, hb_position_t *y)
450 {
451 if (!get_glyph_v_origin (glyph, x, y) &&
452 get_glyph_h_origin (glyph, x, y))
453 {
454 hb_position_t dx, dy;
455 guess_v_origin_minus_h_origin (glyph, &dx, &dy);
456 *x += dx; *y += dy;
457 }
458 }
459
460 void get_glyph_origin_for_direction (hb_codepoint_t glyph,
461 hb_direction_t direction,
462 hb_position_t *x, hb_position_t *y)
463 {
464 if (likely (HB_DIRECTION_IS_HORIZONTAL (direction)))
465 get_glyph_h_origin_with_fallback (glyph, x, y);
466 else
467 get_glyph_v_origin_with_fallback (glyph, x, y);
468 }
469
470 void add_glyph_h_origin (hb_codepoint_t glyph,
471 hb_position_t *x, hb_position_t *y)
472 {
473 hb_position_t origin_x, origin_y;
474
475 get_glyph_h_origin_with_fallback (glyph, &origin_x, &origin_y);
476
477 *x += origin_x;
478 *y += origin_y;
479 }
480 void add_glyph_v_origin (hb_codepoint_t glyph,
481 hb_position_t *x, hb_position_t *y)
482 {
483 hb_position_t origin_x, origin_y;
484
485 get_glyph_v_origin_with_fallback (glyph, &origin_x, &origin_y);
486
487 *x += origin_x;
488 *y += origin_y;
489 }
490 void add_glyph_origin_for_direction (hb_codepoint_t glyph,
491 hb_direction_t direction,
492 hb_position_t *x, hb_position_t *y)
493 {
494 hb_position_t origin_x, origin_y;
495
496 get_glyph_origin_for_direction (glyph, direction, &origin_x, &origin_y);
497
498 *x += origin_x;
499 *y += origin_y;
500 }
501
502 void subtract_glyph_h_origin (hb_codepoint_t glyph,
503 hb_position_t *x, hb_position_t *y)
504 {
505 hb_position_t origin_x, origin_y;
506
507 get_glyph_h_origin_with_fallback (glyph, &origin_x, &origin_y);
508
509 *x -= origin_x;
510 *y -= origin_y;
511 }
512 void subtract_glyph_v_origin (hb_codepoint_t glyph,
513 hb_position_t *x, hb_position_t *y)
514 {
515 hb_position_t origin_x, origin_y;
516
517 get_glyph_v_origin_with_fallback (glyph, &origin_x, &origin_y);
518
519 *x -= origin_x;
520 *y -= origin_y;
521 }
522 void subtract_glyph_origin_for_direction (hb_codepoint_t glyph,
523 hb_direction_t direction,
524 hb_position_t *x, hb_position_t *y)
525 {
526 hb_position_t origin_x, origin_y;
527
528 get_glyph_origin_for_direction (glyph, direction, &origin_x, &origin_y);
529
530 *x -= origin_x;
531 *y -= origin_y;
532 }
533
534 void get_glyph_kerning_for_direction (hb_codepoint_t first_glyph, hb_codepoint_t second_glyph,
535 hb_direction_t direction,
536 hb_position_t *x, hb_position_t *y)
537 {
538 if (likely (HB_DIRECTION_IS_HORIZONTAL (direction))) {
539 *y = 0;
540 *x = get_glyph_h_kerning (first_glyph, second_glyph);
541 } else {
542 *x = 0;
543 *y = get_glyph_v_kerning (first_glyph, second_glyph);
544 }
545 }
546
547 hb_bool_t get_glyph_extents_for_origin (hb_codepoint_t glyph,
548 hb_direction_t direction,
549 hb_glyph_extents_t *extents)
550 {
551 hb_bool_t ret = get_glyph_extents (glyph, extents);
552
553 if (ret)
554 subtract_glyph_origin_for_direction (glyph, direction, &extents->x_bearing, &extents->y_bearing);
555
556 return ret;
557 }
558
559 hb_bool_t get_glyph_contour_point_for_origin (hb_codepoint_t glyph, unsigned int point_index,
560 hb_direction_t direction,
561 hb_position_t *x, hb_position_t *y)
562 {
563 hb_bool_t ret = get_glyph_contour_point (glyph, point_index, x, y);
564
565 if (ret)
566 subtract_glyph_origin_for_direction (glyph, direction, x, y);
567
568 return ret;
569 }
570
571 /* Generates gidDDD if glyph has no name. */
572 void
573 glyph_to_string (hb_codepoint_t glyph,
574 char *s, unsigned int size)
575 {
576 if (get_glyph_name (glyph, s, size)) return;
577
578 if (size && snprintf (s, size, "gid%u", glyph) < 0)
579 *s = '\0';
580 }
581
582 /* Parses gidDDD and uniUUUU strings automatically. */
583 hb_bool_t
584 glyph_from_string (const char *s, int len, /* -1 means nul-terminated */
585 hb_codepoint_t *glyph)
586 {
587 if (get_glyph_from_name (s, len, glyph)) return true;
588
589 if (len == -1) len = strlen (s);
590
591 /* Straight glyph index. */
592 if (hb_codepoint_parse (s, len, 10, glyph))
593 return true;
594
595 if (len > 3)
596 {
597 /* gidDDD syntax for glyph indices. */
598 if (0 == strncmp (s, "gid", 3) &&
599 hb_codepoint_parse (s + 3, len - 3, 10, glyph))
600 return true;
601
602 /* uniUUUU and other Unicode character indices. */
603 hb_codepoint_t unichar;
604 if (0 == strncmp (s, "uni", 3) &&
605 hb_codepoint_parse (s + 3, len - 3, 16, &unichar) &&
606 get_nominal_glyph (unichar, glyph))
607 return true;
608 }
609
610 return false;
611 }
612
613 void mults_changed ()
614 {
615 signed upem = face->get_upem ();
616 x_mult = ((int64_t) x_scale << 16) / upem;
617 y_mult = ((int64_t) y_scale << 16) / upem;
618 }
619
620 hb_position_t em_mult (int16_t v, int64_t mult)
621 {
622 return (hb_position_t) ((v * mult) >> 16);
623 }
624 hb_position_t em_scalef (float v, int scale)
625 { return (hb_position_t) roundf (v * scale / face->get_upem ()); }
626 float em_fscale (int16_t v, int scale)
627 { return (float) v * scale / face->get_upem (); }
628};
629DECLARE_NULL_INSTANCE (hb_font_t);
630
631
632#endif /* HB_FONT_HH */
633