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 38struct hb_ot_face_metrics_accelerator_t 39{ 40 unsigned int num_metrics; 41 unsigned int num_advances; 42 unsigned int default_advance; 43 const OT::_mtx *table; 44 hb_blob_t *blob; 45 46 inline void init (hb_face_t *face, 47 hb_tag_t _hea_tag, hb_tag_t _mtx_tag, 48 unsigned int default_advance) 49 { 50 this->default_advance = default_advance; 51 this->num_metrics = face->get_num_glyphs (); 52 53 hb_blob_t *_hea_blob = OT::Sanitizer<OT::_hea>::sanitize (face->reference_table (_hea_tag)); 54 const OT::_hea *_hea = OT::Sanitizer<OT::_hea>::lock_instance (_hea_blob); 55 this->num_advances = _hea->numberOfLongMetrics; 56 hb_blob_destroy (_hea_blob); 57 58 this->blob = OT::Sanitizer<OT::_mtx>::sanitize (face->reference_table (_mtx_tag)); 59 if (unlikely (!this->num_advances || 60 2 * (this->num_advances + this->num_metrics) < hb_blob_get_length (this->blob))) 61 { 62 this->num_metrics = this->num_advances = 0; 63 hb_blob_destroy (this->blob); 64 this->blob = hb_blob_get_empty (); 65 } 66 this->table = OT::Sanitizer<OT::_mtx>::lock_instance (this->blob); 67 } 68 69 inline void fini (void) 70 { 71 hb_blob_destroy (this->blob); 72 } 73 74 inline unsigned int get_advance (hb_codepoint_t glyph) const 75 { 76 if (unlikely (glyph >= this->num_metrics)) 77 { 78 /* If this->num_metrics is zero, it means we don't have the metrics table 79 * for this direction: return one EM. Otherwise, it means that the glyph 80 * index is out of bound: return zero. */ 81 if (this->num_metrics) 82 return 0; 83 else 84 return this->default_advance; 85 } 86 87 if (glyph >= this->num_advances) 88 glyph = this->num_advances - 1; 89 90 return this->table->longMetric[glyph].advance; 91 } 92}; 93 94struct hb_ot_face_cmap_accelerator_t 95{ 96 const OT::CmapSubtable *table; 97 const OT::CmapSubtable *uvs_table; 98 hb_blob_t *blob; 99 100 inline void init (hb_face_t *face) 101 { 102 this->blob = OT::Sanitizer<OT::cmap>::sanitize (face->reference_table (HB_OT_TAG_cmap)); 103 const OT::cmap *cmap = OT::Sanitizer<OT::cmap>::lock_instance (this->blob); 104 const OT::CmapSubtable *subtable = NULL; 105 const OT::CmapSubtable *subtable_uvs = NULL; 106 107 /* 32-bit subtables. */ 108 if (!subtable) subtable = cmap->find_subtable (3, 10); 109 if (!subtable) subtable = cmap->find_subtable (0, 6); 110 if (!subtable) subtable = cmap->find_subtable (0, 4); 111 /* 16-bit subtables. */ 112 if (!subtable) subtable = cmap->find_subtable (3, 1); 113 if (!subtable) subtable = cmap->find_subtable (0, 3); 114 if (!subtable) subtable = cmap->find_subtable (0, 2); 115 if (!subtable) subtable = cmap->find_subtable (0, 1); 116 if (!subtable) subtable = cmap->find_subtable (0, 0); 117 /* Meh. */ 118 if (!subtable) subtable = &OT::Null(OT::CmapSubtable); 119 120 /* UVS subtable. */ 121 if (!subtable_uvs) subtable_uvs = cmap->find_subtable (0, 5); 122 /* Meh. */ 123 if (!subtable_uvs) subtable_uvs = &OT::Null(OT::CmapSubtable); 124 125 this->table = subtable; 126 this->uvs_table = subtable_uvs; 127 } 128 129 inline void fini (void) 130 { 131 hb_blob_destroy (this->blob); 132 } 133 134 inline bool get_glyph (hb_codepoint_t unicode, 135 hb_codepoint_t variation_selector, 136 hb_codepoint_t *glyph) const 137 { 138 if (unlikely (variation_selector)) 139 { 140 switch (this->uvs_table->get_glyph_variant (unicode, 141 variation_selector, 142 glyph)) 143 { 144 case OT::GLYPH_VARIANT_NOT_FOUND: return false; 145 case OT::GLYPH_VARIANT_FOUND: return true; 146 case OT::GLYPH_VARIANT_USE_DEFAULT: break; 147 } 148 } 149 150 return this->table->get_glyph (unicode, glyph); 151 } 152}; 153 154 155struct hb_ot_font_t 156{ 157 hb_ot_face_cmap_accelerator_t cmap; 158 hb_ot_face_metrics_accelerator_t h_metrics; 159 hb_ot_face_metrics_accelerator_t v_metrics; 160}; 161 162 163static hb_ot_font_t * 164_hb_ot_font_create (hb_font_t *font) 165{ 166 hb_ot_font_t *ot_font = (hb_ot_font_t *) calloc (1, sizeof (hb_ot_font_t)); 167 hb_face_t *face = font->face; 168 169 if (unlikely (!ot_font)) 170 return NULL; 171 172 unsigned int upem = face->get_upem (); 173 174 ot_font->cmap.init (face); 175 ot_font->h_metrics.init (face, HB_OT_TAG_hhea, HB_OT_TAG_hmtx, upem>>1); 176 ot_font->v_metrics.init (face, HB_OT_TAG_vhea, HB_OT_TAG_vmtx, upem); /* TODO Can we do this lazily? */ 177 178 return ot_font; 179} 180 181static void 182_hb_ot_font_destroy (hb_ot_font_t *ot_font) 183{ 184 ot_font->cmap.fini (); 185 ot_font->h_metrics.fini (); 186 ot_font->v_metrics.fini (); 187 188 free (ot_font); 189} 190 191 192static hb_bool_t 193hb_ot_get_glyph (hb_font_t *font HB_UNUSED, 194 void *font_data, 195 hb_codepoint_t unicode, 196 hb_codepoint_t variation_selector, 197 hb_codepoint_t *glyph, 198 void *user_data HB_UNUSED) 199 200{ 201 const hb_ot_font_t *ot_font = (const hb_ot_font_t *) font_data; 202 return ot_font->cmap.get_glyph (unicode, variation_selector, glyph); 203} 204 205static hb_position_t 206hb_ot_get_glyph_h_advance (hb_font_t *font HB_UNUSED, 207 void *font_data, 208 hb_codepoint_t glyph, 209 void *user_data HB_UNUSED) 210{ 211 const hb_ot_font_t *ot_font = (const hb_ot_font_t *) font_data; 212 return font->em_scale_x (ot_font->h_metrics.get_advance (glyph)); 213} 214 215static hb_position_t 216hb_ot_get_glyph_v_advance (hb_font_t *font HB_UNUSED, 217 void *font_data, 218 hb_codepoint_t glyph, 219 void *user_data HB_UNUSED) 220{ 221 const hb_ot_font_t *ot_font = (const hb_ot_font_t *) font_data; 222 return font->em_scale_y (-ot_font->v_metrics.get_advance (glyph)); 223} 224 225static hb_bool_t 226hb_ot_get_glyph_h_origin (hb_font_t *font HB_UNUSED, 227 void *font_data HB_UNUSED, 228 hb_codepoint_t glyph HB_UNUSED, 229 hb_position_t *x HB_UNUSED, 230 hb_position_t *y HB_UNUSED, 231 void *user_data HB_UNUSED) 232{ 233 /* We always work in the horizontal coordinates. */ 234 return true; 235} 236 237static hb_bool_t 238hb_ot_get_glyph_v_origin (hb_font_t *font HB_UNUSED, 239 void *font_data, 240 hb_codepoint_t glyph, 241 hb_position_t *x, 242 hb_position_t *y, 243 void *user_data HB_UNUSED) 244{ 245 /* TODO */ 246 return false; 247} 248 249static hb_position_t 250hb_ot_get_glyph_h_kerning (hb_font_t *font, 251 void *font_data, 252 hb_codepoint_t left_glyph, 253 hb_codepoint_t right_glyph, 254 void *user_data HB_UNUSED) 255{ 256 /* TODO */ 257 return 0; 258} 259 260static hb_position_t 261hb_ot_get_glyph_v_kerning (hb_font_t *font HB_UNUSED, 262 void *font_data HB_UNUSED, 263 hb_codepoint_t top_glyph HB_UNUSED, 264 hb_codepoint_t bottom_glyph HB_UNUSED, 265 void *user_data HB_UNUSED) 266{ 267 /* OpenType doesn't have vertical-kerning other than GPOS. */ 268 return 0; 269} 270 271static hb_bool_t 272hb_ot_get_glyph_extents (hb_font_t *font HB_UNUSED, 273 void *font_data, 274 hb_codepoint_t glyph, 275 hb_glyph_extents_t *extents, 276 void *user_data HB_UNUSED) 277{ 278 /* TODO */ 279 return false; 280} 281 282static hb_bool_t 283hb_ot_get_glyph_contour_point (hb_font_t *font HB_UNUSED, 284 void *font_data, 285 hb_codepoint_t glyph, 286 unsigned int point_index, 287 hb_position_t *x, 288 hb_position_t *y, 289 void *user_data HB_UNUSED) 290{ 291 /* TODO */ 292 return false; 293} 294 295static hb_bool_t 296hb_ot_get_glyph_name (hb_font_t *font HB_UNUSED, 297 void *font_data, 298 hb_codepoint_t glyph, 299 char *name, unsigned int size, 300 void *user_data HB_UNUSED) 301{ 302 /* TODO */ 303 return false; 304} 305 306static hb_bool_t 307hb_ot_get_glyph_from_name (hb_font_t *font HB_UNUSED, 308 void *font_data, 309 const char *name, int len, /* -1 means nul-terminated */ 310 hb_codepoint_t *glyph, 311 void *user_data HB_UNUSED) 312{ 313 /* TODO */ 314 return false; 315} 316 317 318static hb_font_funcs_t * 319_hb_ot_get_font_funcs (void) 320{ 321 static const hb_font_funcs_t ot_ffuncs = { 322 HB_OBJECT_HEADER_STATIC, 323 324 true, /* immutable */ 325 326 { 327#define HB_FONT_FUNC_IMPLEMENT(name) hb_ot_get_##name, 328 HB_FONT_FUNCS_IMPLEMENT_CALLBACKS 329#undef HB_FONT_FUNC_IMPLEMENT 330 } 331 }; 332 333 return const_cast<hb_font_funcs_t *> (&ot_ffuncs); 334} 335 336 337void 338hb_ot_font_set_funcs (hb_font_t *font) 339{ 340 hb_ot_font_t *ot_font = _hb_ot_font_create (font); 341 if (unlikely (!ot_font)) 342 return; 343 344 hb_font_set_funcs (font, 345 _hb_ot_get_font_funcs (), 346 ot_font, 347 (hb_destroy_func_t) _hb_ot_font_destroy); 348} 349