1 /* 2 * Copyright 2009 Red Hat, Inc. 3 * Copyright 2009 Keith Stribley 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 */ 27 28 #include "hb-private.hh" 29 30 #include "hb-ft.h" 31 32 #include "hb-font-private.hh" 33 34 #include FT_ADVANCES_H 35 #include FT_TRUETYPE_TABLES_H 36 37 38 39 #ifndef HB_DEBUG_FT 40 #define HB_DEBUG_FT (HB_DEBUG+0) 41 #endif 42 43 44 /* TODO: 45 * 46 * In general, this file does a fine job of what it's supposed to do. 47 * There are, however, things that need more work: 48 * 49 * - We don't handle any load_flags. That definitely has API implications. :( 50 * I believe hb_ft_font_create() should take load_flags input. 51 * In particular, FT_Get_Advance() without the NO_HINTING flag seems to be 52 * buggy. 53 * 54 * - We don't handle / allow for emboldening / obliqueing. 55 * 56 * - In the future, we should add constructors to create fonts in font space? 57 * 58 * - FT_Load_Glyph() is exteremely costly. Do something about it? 59 */ 60 61 62 static hb_bool_t 63 hb_ft_get_glyph (hb_font_t *font HB_UNUSED, 64 void *font_data, 65 hb_codepoint_t unicode, 66 hb_codepoint_t variation_selector, 67 hb_codepoint_t *glyph, 68 void *user_data HB_UNUSED) 69 70 { 71 FT_Face ft_face = (FT_Face) font_data; 72 73 #ifdef HAVE_FT_FACE_GETCHARVARIANTINDEX 74 if (unlikely (variation_selector)) { 75 *glyph = FT_Face_GetCharVariantIndex (ft_face, unicode, variation_selector); 76 if (*glyph) 77 return true; 78 } 79 #endif 80 81 *glyph = FT_Get_Char_Index (ft_face, unicode); 82 return *glyph != 0; 83 } 84 85 static hb_position_t 86 hb_ft_get_glyph_h_advance (hb_font_t *font HB_UNUSED, 87 void *font_data, 88 hb_codepoint_t glyph, 89 void *user_data HB_UNUSED) 90 { 91 FT_Face ft_face = (FT_Face) font_data; 92 int load_flags = FT_LOAD_DEFAULT | FT_LOAD_NO_HINTING; 93 FT_Fixed v; 94 95 if (unlikely (FT_Get_Advance (ft_face, glyph, load_flags, &v))) 96 return 0; 97 98 return v >> 10; 99 } 100 101 static hb_position_t 102 hb_ft_get_glyph_v_advance (hb_font_t *font HB_UNUSED, 103 void *font_data, 104 hb_codepoint_t glyph, 105 void *user_data HB_UNUSED) 106 { 107 FT_Face ft_face = (FT_Face) font_data; 108 int load_flags = FT_LOAD_DEFAULT | FT_LOAD_NO_HINTING | FT_LOAD_VERTICAL_LAYOUT; 109 FT_Fixed v; 110 111 if (unlikely (FT_Get_Advance (ft_face, glyph, load_flags, &v))) 112 return 0; 113 114 /* Note: FreeType's vertical metrics grows downward while other FreeType coordinates 115 * have a Y growing upward. Hence the extra negation. */ 116 return -v >> 10; 117 } 118 119 static hb_bool_t 120 hb_ft_get_glyph_h_origin (hb_font_t *font HB_UNUSED, 121 void *font_data HB_UNUSED, 122 hb_codepoint_t glyph HB_UNUSED, 123 hb_position_t *x HB_UNUSED, 124 hb_position_t *y HB_UNUSED, 125 void *user_data HB_UNUSED) 126 { 127 /* We always work in the horizontal coordinates. */ 128 return true; 129 } 130 131 static hb_bool_t 132 hb_ft_get_glyph_v_origin (hb_font_t *font HB_UNUSED, 133 void *font_data, 134 hb_codepoint_t glyph, 135 hb_position_t *x, 136 hb_position_t *y, 137 void *user_data HB_UNUSED) 138 { 139 FT_Face ft_face = (FT_Face) font_data; 140 int load_flags = FT_LOAD_DEFAULT; 141 142 if (unlikely (FT_Load_Glyph (ft_face, glyph, load_flags))) 143 return false; 144 145 /* Note: FreeType's vertical metrics grows downward while other FreeType coordinates 146 * have a Y growing upward. Hence the extra negation. */ 147 *x = ft_face->glyph->metrics.horiBearingX - ft_face->glyph->metrics.vertBearingX; 148 *y = ft_face->glyph->metrics.horiBearingY - (-ft_face->glyph->metrics.vertBearingY); 149 150 return true; 151 } 152 153 static hb_position_t 154 hb_ft_get_glyph_h_kerning (hb_font_t *font, 155 void *font_data, 156 hb_codepoint_t left_glyph, 157 hb_codepoint_t right_glyph, 158 void *user_data HB_UNUSED) 159 { 160 FT_Face ft_face = (FT_Face) font_data; 161 FT_Vector kerningv; 162 163 FT_Kerning_Mode mode = font->x_ppem ? FT_KERNING_DEFAULT : FT_KERNING_UNFITTED; 164 if (FT_Get_Kerning (ft_face, left_glyph, right_glyph, mode, &kerningv)) 165 return 0; 166 167 return kerningv.x; 168 } 169 170 static hb_position_t 171 hb_ft_get_glyph_v_kerning (hb_font_t *font HB_UNUSED, 172 void *font_data HB_UNUSED, 173 hb_codepoint_t top_glyph HB_UNUSED, 174 hb_codepoint_t bottom_glyph HB_UNUSED, 175 void *user_data HB_UNUSED) 176 { 177 /* FreeType API doesn't support vertical kerning */ 178 return 0; 179 } 180 181 static hb_bool_t 182 hb_ft_get_glyph_extents (hb_font_t *font HB_UNUSED, 183 void *font_data, 184 hb_codepoint_t glyph, 185 hb_glyph_extents_t *extents, 186 void *user_data HB_UNUSED) 187 { 188 FT_Face ft_face = (FT_Face) font_data; 189 int load_flags = FT_LOAD_DEFAULT; 190 191 if (unlikely (FT_Load_Glyph (ft_face, glyph, load_flags))) 192 return false; 193 194 extents->x_bearing = ft_face->glyph->metrics.horiBearingX; 195 extents->y_bearing = ft_face->glyph->metrics.horiBearingY; 196 extents->width = ft_face->glyph->metrics.width; 197 extents->height = -ft_face->glyph->metrics.height; 198 return true; 199 } 200 201 static hb_bool_t 202 hb_ft_get_glyph_contour_point (hb_font_t *font HB_UNUSED, 203 void *font_data, 204 hb_codepoint_t glyph, 205 unsigned int point_index, 206 hb_position_t *x, 207 hb_position_t *y, 208 void *user_data HB_UNUSED) 209 { 210 FT_Face ft_face = (FT_Face) font_data; 211 int load_flags = FT_LOAD_DEFAULT; 212 213 if (unlikely (FT_Load_Glyph (ft_face, glyph, load_flags))) 214 return false; 215 216 if (unlikely (ft_face->glyph->format != FT_GLYPH_FORMAT_OUTLINE)) 217 return false; 218 219 if (unlikely (point_index >= (unsigned int) ft_face->glyph->outline.n_points)) 220 return false; 221 222 *x = ft_face->glyph->outline.points[point_index].x; 223 *y = ft_face->glyph->outline.points[point_index].y; 224 225 return true; 226 } 227 228 static hb_bool_t 229 hb_ft_get_glyph_name (hb_font_t *font HB_UNUSED, 230 void *font_data, 231 hb_codepoint_t glyph, 232 char *name, unsigned int size, 233 void *user_data HB_UNUSED) 234 { 235 FT_Face ft_face = (FT_Face) font_data; 236 237 hb_bool_t ret = !FT_Get_Glyph_Name (ft_face, glyph, name, size); 238 if (ret && (size && !*name)) 239 ret = false; 240 241 return ret; 242 } 243 244 static hb_bool_t 245 hb_ft_get_glyph_from_name (hb_font_t *font HB_UNUSED, 246 void *font_data, 247 const char *name, int len, /* -1 means nul-terminated */ 248 hb_codepoint_t *glyph, 249 void *user_data HB_UNUSED) 250 { 251 FT_Face ft_face = (FT_Face) font_data; 252 253 if (len < 0) 254 *glyph = FT_Get_Name_Index (ft_face, (FT_String *) name); 255 else { 256 /* Make a nul-terminated version. */ 257 char buf[128]; 258 len = MIN (len, (int) sizeof (buf) - 1); 259 strncpy (buf, name, len); 260 buf[len] = '\0'; 261 *glyph = FT_Get_Name_Index (ft_face, buf); 262 } 263 264 return *glyph != 0; 265 } 266 267 268 static hb_font_funcs_t * 269 _hb_ft_get_font_funcs (void) 270 { 271 static const hb_font_funcs_t ft_ffuncs = { 272 HB_OBJECT_HEADER_STATIC, 273 274 true, /* immutable */ 275 276 { 277 #define HB_FONT_FUNC_IMPLEMENT(name) hb_ft_get_##name, 278 HB_FONT_FUNCS_IMPLEMENT_CALLBACKS 279 #undef HB_FONT_FUNC_IMPLEMENT 280 } 281 }; 282 283 return const_cast<hb_font_funcs_t *> (&ft_ffuncs); 284 } 285 286 287 static hb_blob_t * 288 reference_table (hb_face_t *face HB_UNUSED, hb_tag_t tag, void *user_data) 289 { 290 FT_Face ft_face = (FT_Face) user_data; 291 FT_Byte *buffer; 292 FT_ULong length = 0; 293 FT_Error error; 294 295 /* Note: FreeType like HarfBuzz uses the NONE tag for fetching the entire blob */ 296 297 error = FT_Load_Sfnt_Table (ft_face, tag, 0, NULL, &length); 298 if (error) 299 return NULL; 300 301 buffer = (FT_Byte *) malloc (length); 302 if (buffer == NULL) 303 return NULL; 304 305 error = FT_Load_Sfnt_Table (ft_face, tag, 0, buffer, &length); 306 if (error) 307 return NULL; 308 309 return hb_blob_create ((const char *) buffer, length, 310 HB_MEMORY_MODE_WRITABLE, 311 buffer, free); 312 } 313 314 315 hb_face_t * 316 hb_ft_face_create (FT_Face ft_face, 317 hb_destroy_func_t destroy) 318 { 319 hb_face_t *face; 320 321 if (ft_face->stream->read == NULL) { 322 hb_blob_t *blob; 323 324 blob = hb_blob_create ((const char *) ft_face->stream->base, 325 (unsigned int) ft_face->stream->size, 326 /* TODO: We assume that it's mmap()'ed, but FreeType code 327 * suggests that there are cases we reach here but font is 328 * not mmapped. For example, when mmap() fails. No idea 329 * how to deal with it better here. */ 330 HB_MEMORY_MODE_READONLY_MAY_MAKE_WRITABLE, 331 ft_face, destroy); 332 face = hb_face_create (blob, ft_face->face_index); 333 hb_blob_destroy (blob); 334 } else { 335 face = hb_face_create_for_tables (reference_table, ft_face, destroy); 336 } 337 338 hb_face_set_index (face, ft_face->face_index); 339 hb_face_set_upem (face, ft_face->units_per_EM); 340 341 return face; 342 } 343 344 static void 345 hb_ft_face_finalize (FT_Face ft_face) 346 { 347 hb_face_destroy ((hb_face_t *) ft_face->generic.data); 348 } 349 350 hb_face_t * 351 hb_ft_face_create_cached (FT_Face ft_face) 352 { 353 if (unlikely (!ft_face->generic.data || ft_face->generic.finalizer != (FT_Generic_Finalizer) hb_ft_face_finalize)) 354 { 355 if (ft_face->generic.finalizer) 356 ft_face->generic.finalizer (ft_face); 357 358 ft_face->generic.data = hb_ft_face_create (ft_face, NULL); 359 ft_face->generic.finalizer = (FT_Generic_Finalizer) hb_ft_face_finalize; 360 } 361 362 return hb_face_reference ((hb_face_t *) ft_face->generic.data); 363 } 364 365 static void 366 _do_nothing (void) 367 { 368 } 369 370 371 hb_font_t * 372 hb_ft_font_create (FT_Face ft_face, 373 hb_destroy_func_t destroy) 374 { 375 hb_font_t *font; 376 hb_face_t *face; 377 378 face = hb_ft_face_create (ft_face, destroy); 379 font = hb_font_create (face); 380 hb_face_destroy (face); 381 hb_font_set_funcs (font, 382 _hb_ft_get_font_funcs (), 383 ft_face, (hb_destroy_func_t) _do_nothing); 384 hb_font_set_scale (font, 385 ((uint64_t) ft_face->size->metrics.x_scale * (uint64_t) ft_face->units_per_EM) >> 16, 386 ((uint64_t) ft_face->size->metrics.y_scale * (uint64_t) ft_face->units_per_EM) >> 16); 387 hb_font_set_ppem (font, 388 ft_face->size->metrics.x_ppem, 389 ft_face->size->metrics.y_ppem); 390 391 return font; 392 } 393 394 395 /* Thread-safe, lock-free, FT_Library */ 396 397 static FT_Library ft_library; 398 399 static inline 400 void free_ft_library (void) 401 { 402 FT_Done_FreeType (ft_library); 403 } 404 405 static FT_Library 406 get_ft_library (void) 407 { 408 retry: 409 FT_Library library = (FT_Library) hb_atomic_ptr_get (&ft_library); 410 411 if (unlikely (!library)) 412 { 413 /* Not found; allocate one. */ 414 if (FT_Init_FreeType (&library)) 415 return NULL; 416 417 if (!hb_atomic_ptr_cmpexch (&ft_library, NULL, library)) { 418 FT_Done_FreeType (library); 419 goto retry; 420 } 421 422 #ifdef HAVE_ATEXIT 423 atexit (free_ft_library); /* First person registers atexit() callback. */ 424 #endif 425 } 426 427 return library; 428 } 429 430 static void 431 _release_blob (FT_Face ft_face) 432 { 433 hb_blob_destroy ((hb_blob_t *) ft_face->generic.data); 434 } 435 436 void 437 hb_ft_font_set_funcs (hb_font_t *font) 438 { 439 hb_blob_t *blob = hb_face_reference_blob (font->face); 440 unsigned int blob_length; 441 const char *blob_data = hb_blob_get_data (blob, &blob_length); 442 if (unlikely (!blob_length)) 443 DEBUG_MSG (FT, font, "Font face has empty blob"); 444 445 FT_Face ft_face = NULL; 446 FT_Error err = FT_New_Memory_Face (get_ft_library (), 447 (const FT_Byte *) blob_data, 448 blob_length, 449 hb_face_get_index (font->face), 450 &ft_face); 451 452 if (unlikely (err)) { 453 hb_blob_destroy (blob); 454 DEBUG_MSG (FT, font, "Font face FT_New_Memory_Face() failed"); 455 return; 456 } 457 458 FT_Select_Charmap (ft_face, FT_ENCODING_UNICODE); 459 460 assert (font->y_scale >= 0); 461 FT_Set_Char_Size (ft_face, 462 font->x_scale, font->y_scale, 463 0, 0); 464 #if 0 465 font->x_ppem * 72 * 64 / font->x_scale, 466 font->y_ppem * 72 * 64 / font->y_scale); 467 #endif 468 469 ft_face->generic.data = blob; 470 ft_face->generic.finalizer = (FT_Generic_Finalizer) _release_blob; 471 472 hb_font_set_funcs (font, 473 _hb_ft_get_font_funcs (), 474 ft_face, 475 (hb_destroy_func_t) FT_Done_Face); 476 } 477 478 FT_Face 479 hb_ft_font_get_face (hb_font_t *font) 480 { 481 if (font->destroy == (hb_destroy_func_t) FT_Done_Face || 482 font->destroy == (hb_destroy_func_t) _do_nothing) 483 return (FT_Face) font->user_data; 484 485 return NULL; 486 } 487
