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-hhea-table.hh"
35 #include "hb-ot-hmtx-table.hh"
36
37
38
39 struct hb_ot_font_t
40 {
41 unsigned int num_glyphs;
42 unsigned int num_hmetrics;
43 const OT::hmtx *hmtx;
44 hb_blob_t *hmtx_blob;
45
46 const OT::CmapSubtable *cmap;
47 const OT::CmapSubtable *cmap_uvs;
48 hb_blob_t *cmap_blob;
49 };
50
51
52 static hb_ot_font_t *
_hb_ot_font_create(hb_font_t * font)53 _hb_ot_font_create (hb_font_t *font)
54 {
55 hb_ot_font_t *ot_font = (hb_ot_font_t *) calloc (1, sizeof (hb_ot_font_t));
56
57 if (unlikely (!ot_font))
58 return NULL;
59
60 ot_font->num_glyphs = font->face->get_num_glyphs ();
61
62 {
63 hb_blob_t *hhea_blob = OT::Sanitizer<OT::hhea>::sanitize (font->face->reference_table (HB_OT_TAG_hhea));
64 const OT::hhea *hhea = OT::Sanitizer<OT::hhea>::lock_instance (hhea_blob);
65 ot_font->num_hmetrics = hhea->numberOfHMetrics;
66 hb_blob_destroy (hhea_blob);
67 }
68 ot_font->hmtx_blob = OT::Sanitizer<OT::hmtx>::sanitize (font->face->reference_table (HB_OT_TAG_hmtx));
69 if (unlikely (!ot_font->num_hmetrics ||
70 2 * (ot_font->num_hmetrics + ot_font->num_glyphs) < hb_blob_get_length (ot_font->hmtx_blob)))
71 {
72 hb_blob_destroy (ot_font->hmtx_blob);
73 free (ot_font);
74 return NULL;
75 }
76 ot_font->hmtx = OT::Sanitizer<OT::hmtx>::lock_instance (ot_font->hmtx_blob);
77
78 ot_font->cmap_blob = OT::Sanitizer<OT::cmap>::sanitize (font->face->reference_table (HB_OT_TAG_cmap));
79 const OT::cmap *cmap = OT::Sanitizer<OT::cmap>::lock_instance (ot_font->cmap_blob);
80 const OT::CmapSubtable *subtable = NULL;
81 const OT::CmapSubtable *subtable_uvs = NULL;
82
83 /* 32-bit subtables. */
84 if (!subtable) subtable = cmap->find_subtable (0, 6);
85 if (!subtable) subtable = cmap->find_subtable (0, 4);
86 if (!subtable) subtable = cmap->find_subtable (3, 10);
87 /* 16-bit subtables. */
88 if (!subtable) subtable = cmap->find_subtable (0, 3);
89 if (!subtable) subtable = cmap->find_subtable (3, 1);
90 /* Meh. */
91 if (!subtable) subtable = &OT::Null(OT::CmapSubtable);
92
93 /* UVS subtable. */
94 if (!subtable_uvs) subtable_uvs = cmap->find_subtable (0, 5);
95 /* Meh. */
96 if (!subtable_uvs) subtable_uvs = &OT::Null(OT::CmapSubtable);
97
98 ot_font->cmap = subtable;
99 ot_font->cmap_uvs = subtable_uvs;
100
101 return ot_font;
102 }
103
104 static void
_hb_ot_font_destroy(hb_ot_font_t * ot_font)105 _hb_ot_font_destroy (hb_ot_font_t *ot_font)
106 {
107 hb_blob_destroy (ot_font->cmap_blob);
108 hb_blob_destroy (ot_font->hmtx_blob);
109
110 free (ot_font);
111 }
112
113
114 static hb_bool_t
hb_ot_get_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)115 hb_ot_get_glyph (hb_font_t *font HB_UNUSED,
116 void *font_data,
117 hb_codepoint_t unicode,
118 hb_codepoint_t variation_selector,
119 hb_codepoint_t *glyph,
120 void *user_data HB_UNUSED)
121
122 {
123 const hb_ot_font_t *ot_font = (const hb_ot_font_t *) font_data;
124
125 if (unlikely (variation_selector))
126 {
127 switch (ot_font->cmap_uvs->get_glyph_variant (unicode,
128 variation_selector,
129 glyph))
130 {
131 case OT::GLYPH_VARIANT_NOT_FOUND: return false;
132 case OT::GLYPH_VARIANT_FOUND: return true;
133 case OT::GLYPH_VARIANT_USE_DEFAULT: break;
134 }
135 }
136
137 return ot_font->cmap->get_glyph (unicode, glyph);
138 }
139
140 static hb_position_t
hb_ot_get_glyph_h_advance(hb_font_t * font HB_UNUSED,void * font_data,hb_codepoint_t glyph,void * user_data HB_UNUSED)141 hb_ot_get_glyph_h_advance (hb_font_t *font HB_UNUSED,
142 void *font_data,
143 hb_codepoint_t glyph,
144 void *user_data HB_UNUSED)
145 {
146 const hb_ot_font_t *ot_font = (const hb_ot_font_t *) font_data;
147
148 if (unlikely (glyph >= ot_font->num_glyphs))
149 return 0; /* Maybe better to return notdef's advance instead? */
150
151 if (glyph >= ot_font->num_hmetrics)
152 glyph = ot_font->num_hmetrics - 1;
153
154 return font->em_scale_x (ot_font->hmtx->longHorMetric[glyph].advanceWidth);
155 }
156
157 static hb_position_t
hb_ot_get_glyph_v_advance(hb_font_t * font HB_UNUSED,void * font_data,hb_codepoint_t glyph,void * user_data HB_UNUSED)158 hb_ot_get_glyph_v_advance (hb_font_t *font HB_UNUSED,
159 void *font_data,
160 hb_codepoint_t glyph,
161 void *user_data HB_UNUSED)
162 {
163 /* TODO */
164 return 0;
165 }
166
167 static hb_bool_t
hb_ot_get_glyph_h_origin(hb_font_t * font HB_UNUSED,void * font_data HB_UNUSED,hb_codepoint_t glyph HB_UNUSED,hb_position_t * x HB_UNUSED,hb_position_t * y HB_UNUSED,void * user_data HB_UNUSED)168 hb_ot_get_glyph_h_origin (hb_font_t *font HB_UNUSED,
169 void *font_data HB_UNUSED,
170 hb_codepoint_t glyph HB_UNUSED,
171 hb_position_t *x HB_UNUSED,
172 hb_position_t *y HB_UNUSED,
173 void *user_data HB_UNUSED)
174 {
175 /* We always work in the horizontal coordinates. */
176 return true;
177 }
178
179 static hb_bool_t
hb_ot_get_glyph_v_origin(hb_font_t * font HB_UNUSED,void * font_data,hb_codepoint_t glyph,hb_position_t * x,hb_position_t * y,void * user_data HB_UNUSED)180 hb_ot_get_glyph_v_origin (hb_font_t *font HB_UNUSED,
181 void *font_data,
182 hb_codepoint_t glyph,
183 hb_position_t *x,
184 hb_position_t *y,
185 void *user_data HB_UNUSED)
186 {
187 /* TODO */
188 return false;
189 }
190
191 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)192 hb_ot_get_glyph_h_kerning (hb_font_t *font,
193 void *font_data,
194 hb_codepoint_t left_glyph,
195 hb_codepoint_t right_glyph,
196 void *user_data HB_UNUSED)
197 {
198 /* TODO */
199 return 0;
200 }
201
202 static hb_position_t
hb_ot_get_glyph_v_kerning(hb_font_t * font HB_UNUSED,void * font_data HB_UNUSED,hb_codepoint_t top_glyph HB_UNUSED,hb_codepoint_t bottom_glyph HB_UNUSED,void * user_data HB_UNUSED)203 hb_ot_get_glyph_v_kerning (hb_font_t *font HB_UNUSED,
204 void *font_data HB_UNUSED,
205 hb_codepoint_t top_glyph HB_UNUSED,
206 hb_codepoint_t bottom_glyph HB_UNUSED,
207 void *user_data HB_UNUSED)
208 {
209 return 0;
210 }
211
212 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)213 hb_ot_get_glyph_extents (hb_font_t *font HB_UNUSED,
214 void *font_data,
215 hb_codepoint_t glyph,
216 hb_glyph_extents_t *extents,
217 void *user_data HB_UNUSED)
218 {
219 /* TODO */
220 return false;
221 }
222
223 static hb_bool_t
hb_ot_get_glyph_contour_point(hb_font_t * font HB_UNUSED,void * font_data,hb_codepoint_t glyph,unsigned int point_index,hb_position_t * x,hb_position_t * y,void * user_data HB_UNUSED)224 hb_ot_get_glyph_contour_point (hb_font_t *font HB_UNUSED,
225 void *font_data,
226 hb_codepoint_t glyph,
227 unsigned int point_index,
228 hb_position_t *x,
229 hb_position_t *y,
230 void *user_data HB_UNUSED)
231 {
232 /* TODO */
233 return false;
234 }
235
236 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)237 hb_ot_get_glyph_name (hb_font_t *font HB_UNUSED,
238 void *font_data,
239 hb_codepoint_t glyph,
240 char *name, unsigned int size,
241 void *user_data HB_UNUSED)
242 {
243 /* TODO */
244 return false;
245 }
246
247 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)248 hb_ot_get_glyph_from_name (hb_font_t *font HB_UNUSED,
249 void *font_data,
250 const char *name, int len, /* -1 means nul-terminated */
251 hb_codepoint_t *glyph,
252 void *user_data HB_UNUSED)
253 {
254 /* TODO */
255 return false;
256 }
257
258
259 static hb_font_funcs_t *
_hb_ot_get_font_funcs(void)260 _hb_ot_get_font_funcs (void)
261 {
262 static const hb_font_funcs_t ot_ffuncs = {
263 HB_OBJECT_HEADER_STATIC,
264
265 true, /* immutable */
266
267 {
268 #define HB_FONT_FUNC_IMPLEMENT(name) hb_ot_get_##name,
269 HB_FONT_FUNCS_IMPLEMENT_CALLBACKS
270 #undef HB_FONT_FUNC_IMPLEMENT
271 }
272 };
273
274 return const_cast<hb_font_funcs_t *> (&ot_ffuncs);
275 }
276
277
278 void
hb_ot_font_set_funcs(hb_font_t * font)279 hb_ot_font_set_funcs (hb_font_t *font)
280 {
281 hb_ot_font_t *ot_font = _hb_ot_font_create (font);
282 if (unlikely (!ot_font))
283 return;
284
285 hb_font_set_funcs (font,
286 _hb_ot_get_font_funcs (),
287 ot_font,
288 (hb_destroy_func_t) _hb_ot_font_destroy);
289 }
290