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 return *glyph != 0; 77 } 78 #endif 79 80 *glyph = FT_Get_Char_Index (ft_face, unicode); 81 return *glyph != 0; 82 } 83 84 static hb_position_t 85 hb_ft_get_glyph_h_advance (hb_font_t *font HB_UNUSED, 86 void *font_data, 87 hb_codepoint_t glyph, 88 void *user_data HB_UNUSED) 89 { 90 FT_Face ft_face = (FT_Face) font_data; 91 int load_flags = FT_LOAD_DEFAULT | FT_LOAD_NO_HINTING; 92 FT_Fixed v; 93 94 if (unlikely (FT_Get_Advance (ft_face, glyph, load_flags, &v))) 95 return 0; 96 97 return (v + (1<<9)) >> 10; 98 } 99 100 static hb_position_t 101 hb_ft_get_glyph_v_advance (hb_font_t *font HB_UNUSED, 102 void *font_data, 103 hb_codepoint_t glyph, 104 void *user_data HB_UNUSED) 105 { 106 FT_Face ft_face = (FT_Face) font_data; 107 int load_flags = FT_LOAD_DEFAULT | FT_LOAD_NO_HINTING | FT_LOAD_VERTICAL_LAYOUT; 108 FT_Fixed v; 109 110 if (unlikely (FT_Get_Advance (ft_face, glyph, load_flags, &v))) 111 return 0; 112 113 /* Note: FreeType's vertical metrics grows downward while other FreeType coordinates 114 * have a Y growing upward. Hence the extra negation. */ 115 return (-v + (1<<9)) >> 10; 116 } 117 118 static hb_bool_t 119 hb_ft_get_glyph_h_origin (hb_font_t *font HB_UNUSED, 120 void *font_data HB_UNUSED, 121 hb_codepoint_t glyph HB_UNUSED, 122 hb_position_t *x HB_UNUSED, 123 hb_position_t *y HB_UNUSED, 124 void *user_data HB_UNUSED) 125 { 126 /* We always work in the horizontal coordinates. */ 127 return true; 128 } 129 130 static hb_bool_t 131 hb_ft_get_glyph_v_origin (hb_font_t *font HB_UNUSED, 132 void *font_data, 133 hb_codepoint_t glyph, 134 hb_position_t *x, 135 hb_position_t *y, 136 void *user_data HB_UNUSED) 137 { 138 FT_Face ft_face = (FT_Face) font_data; 139 int load_flags = FT_LOAD_DEFAULT; 140 141 if (unlikely (FT_Load_Glyph (ft_face, glyph, load_flags))) 142 return false; 143 144 /* Note: FreeType's vertical metrics grows downward while other FreeType coordinates 145 * have a Y growing upward. Hence the extra negation. */ 146 *x = ft_face->glyph->metrics.horiBearingX - ft_face->glyph->metrics.vertBearingX; 147 *y = ft_face->glyph->metrics.horiBearingY - (-ft_face->glyph->metrics.vertBearingY); 148 149 return true; 150 } 151 152 static hb_position_t 153 hb_ft_get_glyph_h_kerning (hb_font_t *font, 154 void *font_data, 155 hb_codepoint_t left_glyph, 156 hb_codepoint_t right_glyph, 157 void *user_data HB_UNUSED) 158 { 159 FT_Face ft_face = (FT_Face) font_data; 160 FT_Vector kerningv; 161 162 FT_Kerning_Mode mode = font->x_ppem ? FT_KERNING_DEFAULT : FT_KERNING_UNFITTED; 163 if (FT_Get_Kerning (ft_face, left_glyph, right_glyph, mode, &kerningv)) 164 return 0; 165 166 return kerningv.x; 167 } 168 169 static hb_position_t 170 hb_ft_get_glyph_v_kerning (hb_font_t *font HB_UNUSED, 171 void *font_data HB_UNUSED, 172 hb_codepoint_t top_glyph HB_UNUSED, 173 hb_codepoint_t bottom_glyph HB_UNUSED, 174 void *user_data HB_UNUSED) 175 { 176 /* FreeType API doesn't support vertical kerning */ 177 return 0; 178 } 179 180 static hb_bool_t 181 hb_ft_get_glyph_extents (hb_font_t *font HB_UNUSED, 182 void *font_data, 183 hb_codepoint_t glyph, 184 hb_glyph_extents_t *extents, 185 void *user_data HB_UNUSED) 186 { 187 FT_Face ft_face = (FT_Face) font_data; 188 int load_flags = FT_LOAD_DEFAULT; 189 190 if (unlikely (FT_Load_Glyph (ft_face, glyph, load_flags))) 191 return false; 192 193 extents->x_bearing = ft_face->glyph->metrics.horiBearingX; 194 extents->y_bearing = ft_face->glyph->metrics.horiBearingY; 195 extents->width = ft_face->glyph->metrics.width; 196 extents->height = -ft_face->glyph->metrics.height; 197 return true; 198 } 199 200 static hb_bool_t 201 hb_ft_get_glyph_contour_point (hb_font_t *font HB_UNUSED, 202 void *font_data, 203 hb_codepoint_t glyph, 204 unsigned int point_index, 205 hb_position_t *x, 206 hb_position_t *y, 207 void *user_data HB_UNUSED) 208 { 209 FT_Face ft_face = (FT_Face) font_data; 210 int load_flags = FT_LOAD_DEFAULT; 211 212 if (unlikely (FT_Load_Glyph (ft_face, glyph, load_flags))) 213 return false; 214 215 if (unlikely (ft_face->glyph->format != FT_GLYPH_FORMAT_OUTLINE)) 216 return false; 217 218 if (unlikely (point_index >= (unsigned int) ft_face->glyph->outline.n_points)) 219 return false; 220 221 *x = ft_face->glyph->outline.points[point_index].x; 222 *y = ft_face->glyph->outline.points[point_index].y; 223 224 return true; 225 } 226 227 static hb_bool_t 228 hb_ft_get_glyph_name (hb_font_t *font HB_UNUSED, 229 void *font_data, 230 hb_codepoint_t glyph, 231 char *name, unsigned int size, 232 void *user_data HB_UNUSED) 233 { 234 FT_Face ft_face = (FT_Face) font_data; 235 236 hb_bool_t ret = !FT_Get_Glyph_Name (ft_face, glyph, name, size); 237 if (ret && (size && !*name)) 238 ret = false; 239 240 return ret; 241 } 242 243 static hb_bool_t 244 hb_ft_get_glyph_from_name (hb_font_t *font HB_UNUSED, 245 void *font_data, 246 const char *name, int len, /* -1 means nul-terminated */ 247 hb_codepoint_t *glyph, 248 void *user_data HB_UNUSED) 249 { 250 FT_Face ft_face = (FT_Face) font_data; 251 252 if (len < 0) 253 *glyph = FT_Get_Name_Index (ft_face, (FT_String *) name); 254 else { 255 /* Make a nul-terminated version. */ 256 char buf[128]; 257 len = MIN (len, (int) sizeof (buf) - 1); 258 strncpy (buf, name, len); 259 buf[len] = '\0'; 260 *glyph = FT_Get_Name_Index (ft_face, buf); 261 } 262 263 if (*glyph == 0) 264 { 265 /* Check whether the given name was actually the name of glyph 0. */ 266 char buf[128]; 267 if (!FT_Get_Glyph_Name(ft_face, 0, buf, sizeof (buf)) && 268 len < 0 ? !strcmp (buf, name) : !strncmp (buf, name, len)) 269 return true; 270 } 271 272 return *glyph != 0; 273 } 274 275 276 static hb_font_funcs_t * 277 _hb_ft_get_font_funcs (void) 278 { 279 static const hb_font_funcs_t ft_ffuncs = { 280 HB_OBJECT_HEADER_STATIC, 281 282 true, /* immutable */ 283 284 { 285 #define HB_FONT_FUNC_IMPLEMENT(name) hb_ft_get_##name, 286 HB_FONT_FUNCS_IMPLEMENT_CALLBACKS 287 #undef HB_FONT_FUNC_IMPLEMENT 288 } 289 }; 290 291 return const_cast<hb_font_funcs_t *> (&ft_ffuncs); 292 } 293 294 295 static hb_blob_t * 296 reference_table (hb_face_t *face HB_UNUSED, hb_tag_t tag, void *user_data) 297 { 298 FT_Face ft_face = (FT_Face) user_data; 299 FT_Byte *buffer; 300 FT_ULong length = 0; 301 FT_Error error; 302 303 /* Note: FreeType like HarfBuzz uses the NONE tag for fetching the entire blob */ 304 305 error = FT_Load_Sfnt_Table (ft_face, tag, 0, NULL, &length); 306 if (error) 307 return NULL; 308 309 buffer = (FT_Byte *) malloc (length); 310 if (buffer == NULL) 311 return NULL; 312 313 error = FT_Load_Sfnt_Table (ft_face, tag, 0, buffer, &length); 314 if (error) 315 return NULL; 316 317 return hb_blob_create ((const char *) buffer, length, 318 HB_MEMORY_MODE_WRITABLE, 319 buffer, free); 320 } 321 322 /** 323 * hb_ft_face_create: 324 * @ft_face: (destroy destroy) (scope notified): 325 * @destroy: 326 * 327 * 328 * 329 * Return value: (transfer full): 330 * Since: 1.0 331 **/ 332 hb_face_t * 333 hb_ft_face_create (FT_Face ft_face, 334 hb_destroy_func_t destroy) 335 { 336 hb_face_t *face; 337 338 if (ft_face->stream->read == NULL) { 339 hb_blob_t *blob; 340 341 blob = hb_blob_create ((const char *) ft_face->stream->base, 342 (unsigned int) ft_face->stream->size, 343 /* TODO: We assume that it's mmap()'ed, but FreeType code 344 * suggests that there are cases we reach here but font is 345 * not mmapped. For example, when mmap() fails. No idea 346 * how to deal with it better here. */ 347 HB_MEMORY_MODE_READONLY_MAY_MAKE_WRITABLE, 348 ft_face, destroy); 349 face = hb_face_create (blob, ft_face->face_index); 350 hb_blob_destroy (blob); 351 } else { 352 face = hb_face_create_for_tables (reference_table, ft_face, destroy); 353 } 354 355 hb_face_set_index (face, ft_face->face_index); 356 hb_face_set_upem (face, ft_face->units_per_EM); 357 358 return face; 359 } 360 361 static void 362 hb_ft_face_finalize (FT_Face ft_face) 363 { 364 hb_face_destroy ((hb_face_t *) ft_face->generic.data); 365 } 366 367 /** 368 * hb_ft_face_create_cached: 369 * @ft_face: 370 * 371 * 372 * 373 * Return value: (transfer full): 374 * Since: 1.0 375 **/ 376 hb_face_t * 377 hb_ft_face_create_cached (FT_Face ft_face) 378 { 379 if (unlikely (!ft_face->generic.data || ft_face->generic.finalizer != (FT_Generic_Finalizer) hb_ft_face_finalize)) 380 { 381 if (ft_face->generic.finalizer) 382 ft_face->generic.finalizer (ft_face); 383 384 ft_face->generic.data = hb_ft_face_create (ft_face, NULL); 385 ft_face->generic.finalizer = (FT_Generic_Finalizer) hb_ft_face_finalize; 386 } 387 388 return hb_face_reference ((hb_face_t *) ft_face->generic.data); 389 } 390 391 static void 392 _do_nothing (void) 393 { 394 } 395 396 397 /** 398 * hb_ft_font_create: 399 * @ft_face: (destroy destroy) (scope notified): 400 * @destroy: 401 * 402 * 403 * 404 * Return value: (transfer full): 405 * Since: 1.0 406 **/ 407 hb_font_t * 408 hb_ft_font_create (FT_Face ft_face, 409 hb_destroy_func_t destroy) 410 { 411 hb_font_t *font; 412 hb_face_t *face; 413 414 face = hb_ft_face_create (ft_face, destroy); 415 font = hb_font_create (face); 416 hb_face_destroy (face); 417 hb_font_set_funcs (font, 418 _hb_ft_get_font_funcs (), 419 ft_face, (hb_destroy_func_t) _do_nothing); 420 hb_font_set_scale (font, 421 (int) (((uint64_t) ft_face->size->metrics.x_scale * (uint64_t) ft_face->units_per_EM + (1<<15)) >> 16), 422 (int) (((uint64_t) ft_face->size->metrics.y_scale * (uint64_t) ft_face->units_per_EM + (1<<15)) >> 16)); 423 hb_font_set_ppem (font, 424 ft_face->size->metrics.x_ppem, 425 ft_face->size->metrics.y_ppem); 426 427 return font; 428 } 429 430 431 /* Thread-safe, lock-free, FT_Library */ 432 433 static FT_Library ft_library; 434 435 static inline 436 void free_ft_library (void) 437 { 438 FT_Done_FreeType (ft_library); 439 } 440 441 static FT_Library 442 get_ft_library (void) 443 { 444 retry: 445 FT_Library library = (FT_Library) hb_atomic_ptr_get (&ft_library); 446 447 if (unlikely (!library)) 448 { 449 /* Not found; allocate one. */ 450 if (FT_Init_FreeType (&library)) 451 return NULL; 452 453 if (!hb_atomic_ptr_cmpexch (&ft_library, NULL, library)) { 454 FT_Done_FreeType (library); 455 goto retry; 456 } 457 458 #ifdef HAVE_ATEXIT 459 atexit (free_ft_library); /* First person registers atexit() callback. */ 460 #endif 461 } 462 463 return library; 464 } 465 466 static void 467 _release_blob (FT_Face ft_face) 468 { 469 hb_blob_destroy ((hb_blob_t *) ft_face->generic.data); 470 } 471 472 void 473 hb_ft_font_set_funcs (hb_font_t *font) 474 { 475 hb_blob_t *blob = hb_face_reference_blob (font->face); 476 unsigned int blob_length; 477 const char *blob_data = hb_blob_get_data (blob, &blob_length); 478 if (unlikely (!blob_length)) 479 DEBUG_MSG (FT, font, "Font face has empty blob"); 480 481 FT_Face ft_face = NULL; 482 FT_Error err = FT_New_Memory_Face (get_ft_library (), 483 (const FT_Byte *) blob_data, 484 blob_length, 485 hb_face_get_index (font->face), 486 &ft_face); 487 488 if (unlikely (err)) { 489 hb_blob_destroy (blob); 490 DEBUG_MSG (FT, font, "Font face FT_New_Memory_Face() failed"); 491 return; 492 } 493 494 FT_Select_Charmap (ft_face, FT_ENCODING_UNICODE); 495 496 assert (font->y_scale >= 0); 497 FT_Set_Char_Size (ft_face, 498 font->x_scale, font->y_scale, 499 0, 0); 500 #if 0 501 font->x_ppem * 72 * 64 / font->x_scale, 502 font->y_ppem * 72 * 64 / font->y_scale); 503 #endif 504 505 ft_face->generic.data = blob; 506 ft_face->generic.finalizer = (FT_Generic_Finalizer) _release_blob; 507 508 hb_font_set_funcs (font, 509 _hb_ft_get_font_funcs (), 510 ft_face, 511 (hb_destroy_func_t) FT_Done_Face); 512 } 513 514 FT_Face 515 hb_ft_font_get_face (hb_font_t *font) 516 { 517 if (font->destroy == (hb_destroy_func_t) FT_Done_Face || 518 font->destroy == (hb_destroy_func_t) _do_nothing) 519 return (FT_Face) font->user_data; 520 521 return NULL; 522 } 523
