1 /*
2  * Copyright © 2011,2014  Google, Inc.
3  *
4  *  This is part of HarfBuzz, a text shaping library.
5  *
6  * Permission is hereby granted, without written agreement and without
7  * license or royalty fees, to use, copy, modify, and distribute this
8  * software and its documentation for any purpose, provided that the
9  * above copyright notice and the following two paragraphs appear in
10  * all copies of this software.
11  *
12  * IN NO EVENT SHALL THE COPYRIGHT HOLDER BE LIABLE TO ANY PARTY FOR
13  * DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES
14  * ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN
15  * IF THE COPYRIGHT HOLDER HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH
16  * DAMAGE.
17  *
18  * THE COPYRIGHT HOLDER SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING,
19  * BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
20  * FITNESS FOR A PARTICULAR PURPOSE.  THE SOFTWARE PROVIDED HEREUNDER IS
21  * ON AN "AS IS" BASIS, AND THE COPYRIGHT HOLDER HAS NO OBLIGATION TO
22  * PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.
23  *
24  * Google Author(s): Behdad Esfahbod, Roozbeh Pournader
25  */
26 
27 #include "hb-private.hh"
28 
29 #include "hb-ot.h"
30 
31 #include "hb-font-private.hh"
32 
33 #include "hb-ot-cmap-table.hh"
34 #include "hb-ot-glyf-table.hh"
35 #include "hb-ot-hmtx-table.hh"
36 #include "hb-ot-kern-table.hh"
37 #include "hb-ot-post-table.hh"
38 
39 #include "hb-ot-color-cbdt-table.hh"
40 
41 
42 struct hb_ot_font_t
43 {
44   OT::cmap::accelerator_t cmap;
45   OT::hmtx::accelerator_t h_metrics;
46   OT::vmtx::accelerator_t v_metrics;
47   OT::hb_lazy_loader_t<OT::glyf::accelerator_t> glyf;
48   OT::hb_lazy_loader_t<OT::CBDT::accelerator_t> cbdt;
49   OT::hb_lazy_loader_t<OT::post::accelerator_t> post;
50   OT::hb_lazy_loader_t<OT::kern::accelerator_t> kern;
51 };
52 
53 
54 static hb_ot_font_t *
_hb_ot_font_create(hb_face_t * face)55 _hb_ot_font_create (hb_face_t *face)
56 {
57   hb_ot_font_t *ot_font = (hb_ot_font_t *) calloc (1, sizeof (hb_ot_font_t));
58 
59   if (unlikely (!ot_font))
60     return nullptr;
61 
62   ot_font->cmap.init (face);
63   ot_font->h_metrics.init (face);
64   ot_font->v_metrics.init (face, ot_font->h_metrics.ascender - ot_font->h_metrics.descender); /* TODO Can we do this lazily? */
65   ot_font->glyf.init (face);
66   ot_font->cbdt.init (face);
67   ot_font->post.init (face);
68   ot_font->kern.init (face);
69 
70   return ot_font;
71 }
72 
73 static void
_hb_ot_font_destroy(void * data)74 _hb_ot_font_destroy (void *data)
75 {
76   hb_ot_font_t *ot_font = (hb_ot_font_t *) data;
77 
78   ot_font->cmap.fini ();
79   ot_font->h_metrics.fini ();
80   ot_font->v_metrics.fini ();
81   ot_font->glyf.fini ();
82   ot_font->cbdt.fini ();
83   ot_font->post.fini ();
84   ot_font->kern.fini ();
85 
86   free (ot_font);
87 }
88 
89 
90 static hb_bool_t
hb_ot_get_nominal_glyph(hb_font_t * font HB_UNUSED,void * font_data,hb_codepoint_t unicode,hb_codepoint_t * glyph,void * user_data HB_UNUSED)91 hb_ot_get_nominal_glyph (hb_font_t *font HB_UNUSED,
92 			 void *font_data,
93 			 hb_codepoint_t unicode,
94 			 hb_codepoint_t *glyph,
95 			 void *user_data HB_UNUSED)
96 
97 {
98   const hb_ot_font_t *ot_font = (const hb_ot_font_t *) font_data;
99   return ot_font->cmap.get_nominal_glyph (unicode, glyph);
100 }
101 
102 static hb_bool_t
hb_ot_get_variation_glyph(hb_font_t * font HB_UNUSED,void * font_data,hb_codepoint_t unicode,hb_codepoint_t variation_selector,hb_codepoint_t * glyph,void * user_data HB_UNUSED)103 hb_ot_get_variation_glyph (hb_font_t *font HB_UNUSED,
104 			   void *font_data,
105 			   hb_codepoint_t unicode,
106 			   hb_codepoint_t variation_selector,
107 			   hb_codepoint_t *glyph,
108 			   void *user_data HB_UNUSED)
109 {
110   const hb_ot_font_t *ot_font = (const hb_ot_font_t *) font_data;
111   return ot_font->cmap.get_variation_glyph (unicode, variation_selector, glyph);
112 }
113 
114 static hb_position_t
hb_ot_get_glyph_h_advance(hb_font_t * font,void * font_data,hb_codepoint_t glyph,void * user_data HB_UNUSED)115 hb_ot_get_glyph_h_advance (hb_font_t *font,
116 			   void *font_data,
117 			   hb_codepoint_t glyph,
118 			   void *user_data HB_UNUSED)
119 {
120   const hb_ot_font_t *ot_font = (const hb_ot_font_t *) font_data;
121   return font->em_scale_x (ot_font->h_metrics.get_advance (glyph, font));
122 }
123 
124 static hb_position_t
hb_ot_get_glyph_v_advance(hb_font_t * font,void * font_data,hb_codepoint_t glyph,void * user_data HB_UNUSED)125 hb_ot_get_glyph_v_advance (hb_font_t *font,
126 			   void *font_data,
127 			   hb_codepoint_t glyph,
128 			   void *user_data HB_UNUSED)
129 {
130   const hb_ot_font_t *ot_font = (const hb_ot_font_t *) font_data;
131   return font->em_scale_y (-(int) ot_font->v_metrics.get_advance (glyph, font));
132 }
133 
134 static hb_position_t
hb_ot_get_glyph_h_kerning(hb_font_t * font,void * font_data,hb_codepoint_t left_glyph,hb_codepoint_t right_glyph,void * user_data HB_UNUSED)135 hb_ot_get_glyph_h_kerning (hb_font_t *font,
136 			   void *font_data,
137 			   hb_codepoint_t left_glyph,
138 			   hb_codepoint_t right_glyph,
139 			   void *user_data HB_UNUSED)
140 {
141   const hb_ot_font_t *ot_font = (const hb_ot_font_t *) font_data;
142   return font->em_scale_x (ot_font->kern->get_h_kerning (left_glyph, right_glyph));
143 }
144 
145 static hb_bool_t
hb_ot_get_glyph_extents(hb_font_t * font HB_UNUSED,void * font_data,hb_codepoint_t glyph,hb_glyph_extents_t * extents,void * user_data HB_UNUSED)146 hb_ot_get_glyph_extents (hb_font_t *font HB_UNUSED,
147 			 void *font_data,
148 			 hb_codepoint_t glyph,
149 			 hb_glyph_extents_t *extents,
150 			 void *user_data HB_UNUSED)
151 {
152   const hb_ot_font_t *ot_font = (const hb_ot_font_t *) font_data;
153   bool ret = ot_font->glyf->get_extents (glyph, extents);
154   if (!ret)
155     ret = ot_font->cbdt->get_extents (glyph, extents);
156   // TODO Hook up side-bearings variations.
157   extents->x_bearing = font->em_scale_x (extents->x_bearing);
158   extents->y_bearing = font->em_scale_y (extents->y_bearing);
159   extents->width     = font->em_scale_x (extents->width);
160   extents->height    = font->em_scale_y (extents->height);
161   return ret;
162 }
163 
164 static hb_bool_t
hb_ot_get_glyph_name(hb_font_t * font HB_UNUSED,void * font_data,hb_codepoint_t glyph,char * name,unsigned int size,void * user_data HB_UNUSED)165 hb_ot_get_glyph_name (hb_font_t *font HB_UNUSED,
166                       void *font_data,
167                       hb_codepoint_t glyph,
168                       char *name, unsigned int size,
169                       void *user_data HB_UNUSED)
170 {
171   const hb_ot_font_t *ot_font = (const hb_ot_font_t *) font_data;
172   return ot_font->post->get_glyph_name (glyph, name, size);
173 }
174 
175 static hb_bool_t
hb_ot_get_glyph_from_name(hb_font_t * font HB_UNUSED,void * font_data,const char * name,int len,hb_codepoint_t * glyph,void * user_data HB_UNUSED)176 hb_ot_get_glyph_from_name (hb_font_t *font HB_UNUSED,
177                            void *font_data,
178                            const char *name, int len,
179                            hb_codepoint_t *glyph,
180                            void *user_data HB_UNUSED)
181 {
182   const hb_ot_font_t *ot_font = (const hb_ot_font_t *) font_data;
183   return ot_font->post->get_glyph_from_name (name, len, glyph);
184 }
185 
186 static hb_bool_t
hb_ot_get_font_h_extents(hb_font_t * font HB_UNUSED,void * font_data,hb_font_extents_t * metrics,void * user_data HB_UNUSED)187 hb_ot_get_font_h_extents (hb_font_t *font HB_UNUSED,
188 			  void *font_data,
189 			  hb_font_extents_t *metrics,
190 			  void *user_data HB_UNUSED)
191 {
192   const hb_ot_font_t *ot_font = (const hb_ot_font_t *) font_data;
193   metrics->ascender = font->em_scale_y (ot_font->h_metrics.ascender);
194   metrics->descender = font->em_scale_y (ot_font->h_metrics.descender);
195   metrics->line_gap = font->em_scale_y (ot_font->h_metrics.line_gap);
196   // TODO Hook up variations.
197   return ot_font->h_metrics.has_font_extents;
198 }
199 
200 static hb_bool_t
hb_ot_get_font_v_extents(hb_font_t * font HB_UNUSED,void * font_data,hb_font_extents_t * metrics,void * user_data HB_UNUSED)201 hb_ot_get_font_v_extents (hb_font_t *font HB_UNUSED,
202 			  void *font_data,
203 			  hb_font_extents_t *metrics,
204 			  void *user_data HB_UNUSED)
205 {
206   const hb_ot_font_t *ot_font = (const hb_ot_font_t *) font_data;
207   metrics->ascender = font->em_scale_x (ot_font->v_metrics.ascender);
208   metrics->descender = font->em_scale_x (ot_font->v_metrics.descender);
209   metrics->line_gap = font->em_scale_x (ot_font->v_metrics.line_gap);
210   // TODO Hook up variations.
211   return ot_font->v_metrics.has_font_extents;
212 }
213 
214 static hb_font_funcs_t *static_ot_funcs = nullptr;
215 
216 #ifdef HB_USE_ATEXIT
217 static
free_static_ot_funcs(void)218 void free_static_ot_funcs (void)
219 {
220   hb_font_funcs_destroy (static_ot_funcs);
221 }
222 #endif
223 
224 static hb_font_funcs_t *
_hb_ot_get_font_funcs(void)225 _hb_ot_get_font_funcs (void)
226 {
227 retry:
228   hb_font_funcs_t *funcs = (hb_font_funcs_t *) hb_atomic_ptr_get (&static_ot_funcs);
229 
230   if (unlikely (!funcs))
231   {
232     funcs = hb_font_funcs_create ();
233 
234     hb_font_funcs_set_font_h_extents_func (funcs, hb_ot_get_font_h_extents, nullptr, nullptr);
235     hb_font_funcs_set_font_v_extents_func (funcs, hb_ot_get_font_v_extents, nullptr, nullptr);
236     hb_font_funcs_set_nominal_glyph_func (funcs, hb_ot_get_nominal_glyph, nullptr, nullptr);
237     hb_font_funcs_set_variation_glyph_func (funcs, hb_ot_get_variation_glyph, nullptr, nullptr);
238     hb_font_funcs_set_glyph_h_advance_func (funcs, hb_ot_get_glyph_h_advance, nullptr, nullptr);
239     hb_font_funcs_set_glyph_v_advance_func (funcs, hb_ot_get_glyph_v_advance, nullptr, nullptr);
240     //hb_font_funcs_set_glyph_h_origin_func (funcs, hb_ot_get_glyph_h_origin, nullptr, nullptr);
241     //hb_font_funcs_set_glyph_v_origin_func (funcs, hb_ot_get_glyph_v_origin, nullptr, nullptr);
242     hb_font_funcs_set_glyph_h_kerning_func (funcs, hb_ot_get_glyph_h_kerning, nullptr, nullptr);
243     //hb_font_funcs_set_glyph_v_kerning_func (funcs, hb_ot_get_glyph_v_kerning, nullptr, nullptr);
244     hb_font_funcs_set_glyph_extents_func (funcs, hb_ot_get_glyph_extents, nullptr, nullptr);
245     //hb_font_funcs_set_glyph_contour_point_func (funcs, hb_ot_get_glyph_contour_point, nullptr, nullptr);
246     hb_font_funcs_set_glyph_name_func (funcs, hb_ot_get_glyph_name, nullptr, nullptr);
247     hb_font_funcs_set_glyph_from_name_func (funcs, hb_ot_get_glyph_from_name, nullptr, nullptr);
248 
249     hb_font_funcs_make_immutable (funcs);
250 
251     if (!hb_atomic_ptr_cmpexch (&static_ot_funcs, nullptr, funcs)) {
252       hb_font_funcs_destroy (funcs);
253       goto retry;
254     }
255 
256 #ifdef HB_USE_ATEXIT
257     atexit (free_static_ot_funcs); /* First person registers atexit() callback. */
258 #endif
259   };
260 
261   return funcs;
262 }
263 
264 
265 /**
266  * hb_ot_font_set_funcs:
267  *
268  * Since: 0.9.28
269  **/
270 void
hb_ot_font_set_funcs(hb_font_t * font)271 hb_ot_font_set_funcs (hb_font_t *font)
272 {
273   hb_ot_font_t *ot_font = _hb_ot_font_create (font->face);
274   if (unlikely (!ot_font))
275     return;
276 
277   hb_font_set_funcs (font,
278 		     _hb_ot_get_font_funcs (),
279 		     ot_font,
280 		     _hb_ot_font_destroy);
281 }
282