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-font.h"
35#include "hb-object-private.hh"
36#include "hb-shaper-private.hh"
37#include "hb-shape-plan-private.hh"
38
39
40
41/*
42 * hb_font_funcs_t
43 */
44
45#define HB_FONT_FUNCS_IMPLEMENT_CALLBACKS \
46  HB_FONT_FUNC_IMPLEMENT (glyph) \
47  HB_FONT_FUNC_IMPLEMENT (glyph_h_advance) \
48  HB_FONT_FUNC_IMPLEMENT (glyph_v_advance) \
49  HB_FONT_FUNC_IMPLEMENT (glyph_h_origin) \
50  HB_FONT_FUNC_IMPLEMENT (glyph_v_origin) \
51  HB_FONT_FUNC_IMPLEMENT (glyph_h_kerning) \
52  HB_FONT_FUNC_IMPLEMENT (glyph_v_kerning) \
53  HB_FONT_FUNC_IMPLEMENT (glyph_extents) \
54  HB_FONT_FUNC_IMPLEMENT (glyph_contour_point) \
55  HB_FONT_FUNC_IMPLEMENT (glyph_name) \
56  HB_FONT_FUNC_IMPLEMENT (glyph_from_name) \
57  /* ^--- Add new callbacks here */
58
59struct hb_font_funcs_t {
60  hb_object_header_t header;
61  ASSERT_POD ();
62
63  hb_bool_t immutable;
64
65  /* Don't access these directly.  Call hb_font_get_*() instead. */
66
67  struct {
68#define HB_FONT_FUNC_IMPLEMENT(name) hb_font_get_##name##_func_t name;
69    HB_FONT_FUNCS_IMPLEMENT_CALLBACKS
70#undef HB_FONT_FUNC_IMPLEMENT
71  } get;
72
73  struct {
74#define HB_FONT_FUNC_IMPLEMENT(name) void *name;
75    HB_FONT_FUNCS_IMPLEMENT_CALLBACKS
76#undef HB_FONT_FUNC_IMPLEMENT
77  } user_data;
78
79  struct {
80#define HB_FONT_FUNC_IMPLEMENT(name) hb_destroy_func_t name;
81    HB_FONT_FUNCS_IMPLEMENT_CALLBACKS
82#undef HB_FONT_FUNC_IMPLEMENT
83  } destroy;
84};
85
86
87/*
88 * hb_face_t
89 */
90
91struct hb_face_t {
92  hb_object_header_t header;
93  ASSERT_POD ();
94
95  hb_bool_t immutable;
96
97  hb_reference_table_func_t  reference_table_func;
98  void                      *user_data;
99  hb_destroy_func_t          destroy;
100
101  unsigned int index;
102  mutable unsigned int upem;
103  mutable unsigned int num_glyphs;
104
105  struct hb_shaper_data_t shaper_data;
106
107  struct plan_node_t {
108    hb_shape_plan_t *shape_plan;
109    plan_node_t *next;
110  } *shape_plans;
111
112
113  inline hb_blob_t *reference_table (hb_tag_t tag) const
114  {
115    hb_blob_t *blob;
116
117    if (unlikely (!this || !reference_table_func))
118      return hb_blob_get_empty ();
119
120    blob = reference_table_func (/*XXX*/const_cast<hb_face_t *> (this), tag, user_data);
121    if (unlikely (!blob))
122      return hb_blob_get_empty ();
123
124    return blob;
125  }
126
127  inline unsigned int get_upem (void) const
128  {
129    if (unlikely (!upem))
130      load_upem ();
131    return upem;
132  }
133
134  inline unsigned int get_num_glyphs (void) const
135  {
136    if (unlikely (num_glyphs == (unsigned int) -1))
137      load_num_glyphs ();
138    return num_glyphs;
139  }
140
141  private:
142  HB_INTERNAL void load_upem (void) const;
143  HB_INTERNAL void load_num_glyphs (void) const;
144};
145
146#define HB_SHAPER_DATA_CREATE_FUNC_EXTRA_ARGS
147#define HB_SHAPER_IMPLEMENT(shaper) HB_SHAPER_DATA_PROTOTYPE(shaper, face);
148#include "hb-shaper-list.hh"
149#undef HB_SHAPER_IMPLEMENT
150#undef HB_SHAPER_DATA_CREATE_FUNC_EXTRA_ARGS
151
152
153/*
154 * hb_font_t
155 */
156
157struct hb_font_t {
158  hb_object_header_t header;
159  ASSERT_POD ();
160
161  hb_bool_t immutable;
162
163  hb_font_t *parent;
164  hb_face_t *face;
165
166  int x_scale;
167  int y_scale;
168
169  unsigned int x_ppem;
170  unsigned int y_ppem;
171
172  hb_font_funcs_t   *klass;
173  void              *user_data;
174  hb_destroy_func_t  destroy;
175
176  struct hb_shaper_data_t shaper_data;
177
178
179  /* Convert from font-space to user-space */
180  inline hb_position_t em_scale_x (int16_t v) { return em_scale (v, this->x_scale); }
181  inline hb_position_t em_scale_y (int16_t v) { return em_scale (v, this->y_scale); }
182
183  /* Convert from parent-font user-space to our user-space */
184  inline hb_position_t parent_scale_x_distance (hb_position_t v) {
185    if (unlikely (parent && parent->x_scale != x_scale))
186      return v * (int64_t) this->x_scale / this->parent->x_scale;
187    return v;
188  }
189  inline hb_position_t parent_scale_y_distance (hb_position_t v) {
190    if (unlikely (parent && parent->y_scale != y_scale))
191      return v * (int64_t) this->y_scale / this->parent->y_scale;
192    return v;
193  }
194  inline hb_position_t parent_scale_x_position (hb_position_t v) {
195    return parent_scale_x_distance (v);
196  }
197  inline hb_position_t parent_scale_y_position (hb_position_t v) {
198    return parent_scale_y_distance (v);
199  }
200
201  inline void parent_scale_distance (hb_position_t *x, hb_position_t *y) {
202    *x = parent_scale_x_distance (*x);
203    *y = parent_scale_y_distance (*y);
204  }
205  inline void parent_scale_position (hb_position_t *x, hb_position_t *y) {
206    *x = parent_scale_x_position (*x);
207    *y = parent_scale_y_position (*y);
208  }
209
210
211  /* Public getters */
212
213  inline hb_bool_t get_glyph (hb_codepoint_t unicode, hb_codepoint_t variation_selector,
214			      hb_codepoint_t *glyph)
215  {
216    *glyph = 0;
217    return klass->get.glyph (this, user_data,
218			     unicode, variation_selector, glyph,
219			     klass->user_data.glyph);
220  }
221
222  inline hb_position_t get_glyph_h_advance (hb_codepoint_t glyph)
223  {
224    return klass->get.glyph_h_advance (this, user_data,
225				       glyph,
226				       klass->user_data.glyph_h_advance);
227  }
228
229  inline hb_position_t get_glyph_v_advance (hb_codepoint_t glyph)
230  {
231    return klass->get.glyph_v_advance (this, user_data,
232				       glyph,
233				       klass->user_data.glyph_v_advance);
234  }
235
236  inline hb_bool_t get_glyph_h_origin (hb_codepoint_t glyph,
237				       hb_position_t *x, hb_position_t *y)
238  {
239    *x = *y = 0;
240    return klass->get.glyph_h_origin (this, user_data,
241				      glyph, x, y,
242				      klass->user_data.glyph_h_origin);
243  }
244
245  inline hb_bool_t get_glyph_v_origin (hb_codepoint_t glyph,
246				       hb_position_t *x, hb_position_t *y)
247  {
248    *x = *y = 0;
249    return klass->get.glyph_v_origin (this, user_data,
250				      glyph, x, y,
251				      klass->user_data.glyph_v_origin);
252  }
253
254  inline hb_position_t get_glyph_h_kerning (hb_codepoint_t left_glyph, hb_codepoint_t right_glyph)
255  {
256    return klass->get.glyph_h_kerning (this, user_data,
257				       left_glyph, right_glyph,
258				       klass->user_data.glyph_h_kerning);
259  }
260
261  inline hb_position_t get_glyph_v_kerning (hb_codepoint_t left_glyph, hb_codepoint_t right_glyph)
262  {
263    return klass->get.glyph_v_kerning (this, user_data,
264				       left_glyph, right_glyph,
265				       klass->user_data.glyph_v_kerning);
266  }
267
268  inline hb_bool_t get_glyph_extents (hb_codepoint_t glyph,
269				      hb_glyph_extents_t *extents)
270  {
271    memset (extents, 0, sizeof (*extents));
272    return klass->get.glyph_extents (this, user_data,
273				     glyph,
274				     extents,
275				     klass->user_data.glyph_extents);
276  }
277
278  inline hb_bool_t get_glyph_contour_point (hb_codepoint_t glyph, unsigned int point_index,
279					    hb_position_t *x, hb_position_t *y)
280  {
281    *x = *y = 0;
282    return klass->get.glyph_contour_point (this, user_data,
283					   glyph, point_index,
284					   x, y,
285					   klass->user_data.glyph_contour_point);
286  }
287
288  inline hb_bool_t get_glyph_name (hb_codepoint_t glyph,
289				   char *name, unsigned int size)
290  {
291    if (size) *name = '\0';
292    return klass->get.glyph_name (this, user_data,
293				  glyph,
294				  name, size,
295				  klass->user_data.glyph_name);
296  }
297
298  inline hb_bool_t get_glyph_from_name (const char *name, int len, /* -1 means nul-terminated */
299					hb_codepoint_t *glyph)
300  {
301    *glyph = 0;
302    if (len == -1) len = strlen (name);
303    return klass->get.glyph_from_name (this, user_data,
304				       name, len,
305				       glyph,
306				       klass->user_data.glyph_from_name);
307  }
308
309
310  /* A bit higher-level, and with fallback */
311
312  inline void get_glyph_advance_for_direction (hb_codepoint_t glyph,
313					       hb_direction_t direction,
314					       hb_position_t *x, hb_position_t *y)
315  {
316    if (likely (HB_DIRECTION_IS_HORIZONTAL (direction))) {
317      *x = get_glyph_h_advance (glyph);
318      *y = 0;
319    } else {
320      *x = 0;
321      *y = get_glyph_v_advance (glyph);
322    }
323  }
324
325  /* Internal only */
326  inline void guess_v_origin_minus_h_origin (hb_codepoint_t glyph,
327					     hb_position_t *x, hb_position_t *y)
328  {
329    *x = get_glyph_h_advance (glyph) / 2;
330
331    /* TODO use font_metics.ascent */
332    *y = y_scale;
333  }
334
335  inline void get_glyph_origin_for_direction (hb_codepoint_t glyph,
336					      hb_direction_t direction,
337					      hb_position_t *x, hb_position_t *y)
338  {
339    if (likely (HB_DIRECTION_IS_HORIZONTAL (direction))) {
340      hb_bool_t ret = get_glyph_h_origin (glyph, x, y);
341      if (!ret && (ret = get_glyph_v_origin (glyph, x, y))) {
342	hb_position_t dx, dy;
343	guess_v_origin_minus_h_origin (glyph, &dx, &dy);
344	*x -= dx; *y -= dy;
345      }
346    } else {
347      hb_bool_t ret = get_glyph_v_origin (glyph, x, y);
348      if (!ret && (ret = get_glyph_h_origin (glyph, x, y))) {
349	hb_position_t dx, dy;
350	guess_v_origin_minus_h_origin (glyph, &dx, &dy);
351	*x += dx; *y += dy;
352      }
353    }
354  }
355
356  inline void add_glyph_origin_for_direction (hb_codepoint_t glyph,
357					      hb_direction_t direction,
358					      hb_position_t *x, hb_position_t *y)
359  {
360    hb_position_t origin_x, origin_y;
361
362    get_glyph_origin_for_direction (glyph, direction, &origin_x, &origin_y);
363
364    *x += origin_x;
365    *y += origin_y;
366  }
367
368  inline void subtract_glyph_origin_for_direction (hb_codepoint_t glyph,
369						   hb_direction_t direction,
370						   hb_position_t *x, hb_position_t *y)
371  {
372    hb_position_t origin_x, origin_y;
373
374    get_glyph_origin_for_direction (glyph, direction, &origin_x, &origin_y);
375
376    *x -= origin_x;
377    *y -= origin_y;
378  }
379
380  inline void get_glyph_kerning_for_direction (hb_codepoint_t first_glyph, hb_codepoint_t second_glyph,
381					       hb_direction_t direction,
382					       hb_position_t *x, hb_position_t *y)
383  {
384    if (likely (HB_DIRECTION_IS_HORIZONTAL (direction))) {
385      *x = get_glyph_h_kerning (first_glyph, second_glyph);
386      *y = 0;
387    } else {
388      *x = 0;
389      *y = get_glyph_v_kerning (first_glyph, second_glyph);
390    }
391  }
392
393  inline hb_bool_t get_glyph_extents_for_origin (hb_codepoint_t glyph,
394						 hb_direction_t direction,
395						 hb_glyph_extents_t *extents)
396  {
397    hb_bool_t ret = get_glyph_extents (glyph, extents);
398
399    if (ret)
400      subtract_glyph_origin_for_direction (glyph, direction, &extents->x_bearing, &extents->y_bearing);
401
402    return ret;
403  }
404
405  inline hb_bool_t get_glyph_contour_point_for_origin (hb_codepoint_t glyph, unsigned int point_index,
406						       hb_direction_t direction,
407						       hb_position_t *x, hb_position_t *y)
408  {
409    hb_bool_t ret = get_glyph_contour_point (glyph, point_index, x, y);
410
411    if (ret)
412      subtract_glyph_origin_for_direction (glyph, direction, x, y);
413
414    return ret;
415  }
416
417  /* Generates gidDDD if glyph has no name. */
418  inline void
419  glyph_to_string (hb_codepoint_t glyph,
420		   char *s, unsigned int size)
421  {
422    if (get_glyph_name (glyph, s, size)) return;
423
424    snprintf (s, size, "gid%u", glyph);
425  }
426
427  /* Parses gidDDD and uniUUUU strings automatically. */
428  inline hb_bool_t
429  glyph_from_string (const char *s, int len, /* -1 means nul-terminated */
430		     hb_codepoint_t *glyph)
431  {
432    if (get_glyph_from_name (s, len, glyph)) return true;
433
434    if (len == -1) len = strlen (s);
435
436    /* Straight glyph index. */
437    if (hb_codepoint_parse (s, len, 10, glyph))
438      return true;
439
440    if (len > 3)
441    {
442      /* gidDDD syntax for glyph indices. */
443      if (0 == strncmp (s, "gid", 3) &&
444	  hb_codepoint_parse (s + 3, len - 3, 10, glyph))
445	return true;
446
447      /* uniUUUU and other Unicode character indices. */
448      hb_codepoint_t unichar;
449      if (0 == strncmp (s, "uni", 3) &&
450	  hb_codepoint_parse (s + 3, len - 3, 16, &unichar) &&
451	  get_glyph (unichar, 0, glyph))
452	return true;
453    }
454
455    return false;
456  }
457
458  private:
459  inline hb_position_t em_scale (int16_t v, int scale) { return v * (int64_t) scale / hb_face_get_upem (this->face); }
460};
461
462#define HB_SHAPER_DATA_CREATE_FUNC_EXTRA_ARGS
463#define HB_SHAPER_IMPLEMENT(shaper) HB_SHAPER_DATA_PROTOTYPE(shaper, font);
464#include "hb-shaper-list.hh"
465#undef HB_SHAPER_IMPLEMENT
466#undef HB_SHAPER_DATA_CREATE_FUNC_EXTRA_ARGS
467
468
469#endif /* HB_FONT_PRIVATE_HH */
470