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 * FreeType works in 26.6 mode. Clients can decide to use that mode, and everything 55 * would work fine. However, we also abuse this API for performing in font-space, 56 * but don't pass the correct flags to FreeType. We just abuse the no-hinting mode 57 * for that, such that no rounding etc happens. As such, we don't set ppem, and 58 * pass NO_HINTING around. This seems to work best, until we go ahead and add a full 59 * load_flags API. 60 * 61 * - We don't handle / allow for emboldening / obliqueing. 62 * 63 * - In the future, we should add constructors to create fonts in font space? 64 * 65 * - FT_Load_Glyph() is exteremely costly. Do something about it? 66 */ 67 68 69 static hb_bool_t 70 hb_ft_get_glyph (hb_font_t *font HB_UNUSED, 71 void *font_data, 72 hb_codepoint_t unicode, 73 hb_codepoint_t variation_selector, 74 hb_codepoint_t *glyph, 75 void *user_data HB_UNUSED) 76 77 { 78 FT_Face ft_face = (FT_Face) font_data; 79 80 if (unlikely (variation_selector)) { 81 *glyph = FT_Face_GetCharVariantIndex (ft_face, unicode, variation_selector); 82 return *glyph != 0; 83 } 84 85 *glyph = FT_Get_Char_Index (ft_face, unicode); 86 return *glyph != 0; 87 } 88 89 static hb_position_t 90 hb_ft_get_glyph_h_advance (hb_font_t *font HB_UNUSED, 91 void *font_data, 92 hb_codepoint_t glyph, 93 void *user_data HB_UNUSED) 94 { 95 FT_Face ft_face = (FT_Face) font_data; 96 int load_flags = FT_LOAD_DEFAULT | FT_LOAD_NO_HINTING; 97 FT_Fixed v; 98 99 if (unlikely (FT_Get_Advance (ft_face, glyph, load_flags, &v))) 100 return 0; 101 102 if (font->x_scale < 0) 103 v = -v; 104 105 return (v + (1<<9)) >> 10; 106 } 107 108 static hb_position_t 109 hb_ft_get_glyph_v_advance (hb_font_t *font HB_UNUSED, 110 void *font_data, 111 hb_codepoint_t glyph, 112 void *user_data HB_UNUSED) 113 { 114 FT_Face ft_face = (FT_Face) font_data; 115 int load_flags = FT_LOAD_DEFAULT | FT_LOAD_NO_HINTING | FT_LOAD_VERTICAL_LAYOUT; 116 FT_Fixed v; 117 118 if (unlikely (FT_Get_Advance (ft_face, glyph, load_flags, &v))) 119 return 0; 120 121 /* Note: FreeType's vertical metrics grows downward while other FreeType coordinates 122 * have a Y growing upward. Hence the extra negation. */ 123 return (-v + (1<<9)) >> 10; 124 } 125 126 static hb_bool_t 127 hb_ft_get_glyph_h_origin (hb_font_t *font HB_UNUSED, 128 void *font_data HB_UNUSED, 129 hb_codepoint_t glyph HB_UNUSED, 130 hb_position_t *x HB_UNUSED, 131 hb_position_t *y HB_UNUSED, 132 void *user_data HB_UNUSED) 133 { 134 /* We always work in the horizontal coordinates. */ 135 return true; 136 } 137 138 static hb_bool_t 139 hb_ft_get_glyph_v_origin (hb_font_t *font HB_UNUSED, 140 void *font_data, 141 hb_codepoint_t glyph, 142 hb_position_t *x, 143 hb_position_t *y, 144 void *user_data HB_UNUSED) 145 { 146 FT_Face ft_face = (FT_Face) font_data; 147 int load_flags = FT_LOAD_DEFAULT | FT_LOAD_NO_HINTING; 148 149 if (unlikely (FT_Load_Glyph (ft_face, glyph, load_flags))) 150 return false; 151 152 /* Note: FreeType's vertical metrics grows downward while other FreeType coordinates 153 * have a Y growing upward. Hence the extra negation. */ 154 *x = ft_face->glyph->metrics.horiBearingX - ft_face->glyph->metrics.vertBearingX; 155 *y = ft_face->glyph->metrics.horiBearingY - (-ft_face->glyph->metrics.vertBearingY); 156 157 return true; 158 } 159 160 static hb_position_t 161 hb_ft_get_glyph_h_kerning (hb_font_t *font, 162 void *font_data, 163 hb_codepoint_t left_glyph, 164 hb_codepoint_t right_glyph, 165 void *user_data HB_UNUSED) 166 { 167 FT_Face ft_face = (FT_Face) font_data; 168 FT_Vector kerningv; 169 170 FT_Kerning_Mode mode = font->x_ppem ? FT_KERNING_DEFAULT : FT_KERNING_UNFITTED; 171 if (FT_Get_Kerning (ft_face, left_glyph, right_glyph, mode, &kerningv)) 172 return 0; 173 174 return kerningv.x; 175 } 176 177 static hb_position_t 178 hb_ft_get_glyph_v_kerning (hb_font_t *font HB_UNUSED, 179 void *font_data HB_UNUSED, 180 hb_codepoint_t top_glyph HB_UNUSED, 181 hb_codepoint_t bottom_glyph HB_UNUSED, 182 void *user_data HB_UNUSED) 183 { 184 /* FreeType API doesn't support vertical kerning */ 185 return 0; 186 } 187 188 static hb_bool_t 189 hb_ft_get_glyph_extents (hb_font_t *font HB_UNUSED, 190 void *font_data, 191 hb_codepoint_t glyph, 192 hb_glyph_extents_t *extents, 193 void *user_data HB_UNUSED) 194 { 195 FT_Face ft_face = (FT_Face) font_data; 196 int load_flags = FT_LOAD_DEFAULT | FT_LOAD_NO_HINTING; 197 198 if (unlikely (FT_Load_Glyph (ft_face, glyph, load_flags))) 199 return false; 200 201 extents->x_bearing = ft_face->glyph->metrics.horiBearingX; 202 extents->y_bearing = ft_face->glyph->metrics.horiBearingY; 203 extents->width = ft_face->glyph->metrics.width; 204 extents->height = -ft_face->glyph->metrics.height; 205 return true; 206 } 207 208 static hb_bool_t 209 hb_ft_get_glyph_contour_point (hb_font_t *font HB_UNUSED, 210 void *font_data, 211 hb_codepoint_t glyph, 212 unsigned int point_index, 213 hb_position_t *x, 214 hb_position_t *y, 215 void *user_data HB_UNUSED) 216 { 217 FT_Face ft_face = (FT_Face) font_data; 218 int load_flags = FT_LOAD_DEFAULT; 219 220 if (unlikely (FT_Load_Glyph (ft_face, glyph, load_flags))) 221 return false; 222 223 if (unlikely (ft_face->glyph->format != FT_GLYPH_FORMAT_OUTLINE)) 224 return false; 225 226 if (unlikely (point_index >= (unsigned int) ft_face->glyph->outline.n_points)) 227 return false; 228 229 *x = ft_face->glyph->outline.points[point_index].x; 230 *y = ft_face->glyph->outline.points[point_index].y; 231 232 return true; 233 } 234 235 static hb_bool_t 236 hb_ft_get_glyph_name (hb_font_t *font HB_UNUSED, 237 void *font_data, 238 hb_codepoint_t glyph, 239 char *name, unsigned int size, 240 void *user_data HB_UNUSED) 241 { 242 FT_Face ft_face = (FT_Face) font_data; 243 244 hb_bool_t ret = !FT_Get_Glyph_Name (ft_face, glyph, name, size); 245 if (ret && (size && !*name)) 246 ret = false; 247 248 return ret; 249 } 250 251 static hb_bool_t 252 hb_ft_get_glyph_from_name (hb_font_t *font HB_UNUSED, 253 void *font_data, 254 const char *name, int len, /* -1 means nul-terminated */ 255 hb_codepoint_t *glyph, 256 void *user_data HB_UNUSED) 257 { 258 FT_Face ft_face = (FT_Face) font_data; 259 260 if (len < 0) 261 *glyph = FT_Get_Name_Index (ft_face, (FT_String *) name); 262 else { 263 /* Make a nul-terminated version. */ 264 char buf[128]; 265 len = MIN (len, (int) sizeof (buf) - 1); 266 strncpy (buf, name, len); 267 buf[len] = '\0'; 268 *glyph = FT_Get_Name_Index (ft_face, buf); 269 } 270 271 if (*glyph == 0) 272 { 273 /* Check whether the given name was actually the name of glyph 0. */ 274 char buf[128]; 275 if (!FT_Get_Glyph_Name(ft_face, 0, buf, sizeof (buf)) && 276 len < 0 ? !strcmp (buf, name) : !strncmp (buf, name, len)) 277 return true; 278 } 279 280 return *glyph != 0; 281 } 282 283 284 static hb_font_funcs_t * 285 _hb_ft_get_font_funcs (void) 286 { 287 static const hb_font_funcs_t ft_ffuncs = { 288 HB_OBJECT_HEADER_STATIC, 289 290 true, /* immutable */ 291 292 { 293 #define HB_FONT_FUNC_IMPLEMENT(name) hb_ft_get_##name, 294 HB_FONT_FUNCS_IMPLEMENT_CALLBACKS 295 #undef HB_FONT_FUNC_IMPLEMENT 296 } 297 }; 298 299 return const_cast<hb_font_funcs_t *> (&ft_ffuncs); 300 } 301 302 303 static hb_blob_t * 304 reference_table (hb_face_t *face HB_UNUSED, hb_tag_t tag, void *user_data) 305 { 306 FT_Face ft_face = (FT_Face) user_data; 307 FT_Byte *buffer; 308 FT_ULong length = 0; 309 FT_Error error; 310 311 /* Note: FreeType like HarfBuzz uses the NONE tag for fetching the entire blob */ 312 313 error = FT_Load_Sfnt_Table (ft_face, tag, 0, NULL, &length); 314 if (error) 315 return NULL; 316 317 buffer = (FT_Byte *) malloc (length); 318 if (buffer == NULL) 319 return NULL; 320 321 error = FT_Load_Sfnt_Table (ft_face, tag, 0, buffer, &length); 322 if (error) 323 return NULL; 324 325 return hb_blob_create ((const char *) buffer, length, 326 HB_MEMORY_MODE_WRITABLE, 327 buffer, free); 328 } 329 330 /** 331 * hb_ft_face_create: 332 * @ft_face: (destroy destroy) (scope notified): 333 * @destroy: 334 * 335 * 336 * 337 * Return value: (transfer full): 338 * Since: 1.0 339 **/ 340 hb_face_t * 341 hb_ft_face_create (FT_Face ft_face, 342 hb_destroy_func_t destroy) 343 { 344 hb_face_t *face; 345 346 if (ft_face->stream->read == NULL) { 347 hb_blob_t *blob; 348 349 blob = hb_blob_create ((const char *) ft_face->stream->base, 350 (unsigned int) ft_face->stream->size, 351 HB_MEMORY_MODE_READONLY, 352 ft_face, destroy); 353 face = hb_face_create (blob, ft_face->face_index); 354 hb_blob_destroy (blob); 355 } else { 356 face = hb_face_create_for_tables (reference_table, ft_face, destroy); 357 } 358 359 hb_face_set_index (face, ft_face->face_index); 360 hb_face_set_upem (face, ft_face->units_per_EM); 361 362 return face; 363 } 364 365 /** 366 * hb_ft_face_create_referenced: 367 * @ft_face: 368 * 369 * 370 * 371 * Return value: (transfer full): 372 * Since: 1.0 373 **/ 374 hb_face_t * 375 hb_ft_face_create_referenced (FT_Face ft_face) 376 { 377 FT_Reference_Face (ft_face); 378 return hb_ft_face_create (ft_face, (hb_destroy_func_t) FT_Done_Face); 379 } 380 381 static void 382 hb_ft_face_finalize (FT_Face ft_face) 383 { 384 hb_face_destroy ((hb_face_t *) ft_face->generic.data); 385 } 386 387 /** 388 * hb_ft_face_create_cached: 389 * @ft_face: 390 * 391 * 392 * 393 * Return value: (transfer full): 394 * Since: 1.0 395 **/ 396 hb_face_t * 397 hb_ft_face_create_cached (FT_Face ft_face) 398 { 399 if (unlikely (!ft_face->generic.data || ft_face->generic.finalizer != (FT_Generic_Finalizer) hb_ft_face_finalize)) 400 { 401 if (ft_face->generic.finalizer) 402 ft_face->generic.finalizer (ft_face); 403 404 ft_face->generic.data = hb_ft_face_create (ft_face, NULL); 405 ft_face->generic.finalizer = (FT_Generic_Finalizer) hb_ft_face_finalize; 406 } 407 408 return hb_face_reference ((hb_face_t *) ft_face->generic.data); 409 } 410 411 static void 412 _do_nothing (void) 413 { 414 } 415 416 417 /** 418 * hb_ft_font_create: 419 * @ft_face: (destroy destroy) (scope notified): 420 * @destroy: 421 * 422 * 423 * 424 * Return value: (transfer full): 425 * Since: 1.0 426 **/ 427 hb_font_t * 428 hb_ft_font_create (FT_Face ft_face, 429 hb_destroy_func_t destroy) 430 { 431 hb_font_t *font; 432 hb_face_t *face; 433 434 face = hb_ft_face_create (ft_face, destroy); 435 font = hb_font_create (face); 436 hb_face_destroy (face); 437 hb_font_set_funcs (font, 438 _hb_ft_get_font_funcs (), 439 ft_face, (hb_destroy_func_t) _do_nothing); 440 hb_font_set_scale (font, 441 (int) (((uint64_t) ft_face->size->metrics.x_scale * (uint64_t) ft_face->units_per_EM + (1<<15)) >> 16), 442 (int) (((uint64_t) ft_face->size->metrics.y_scale * (uint64_t) ft_face->units_per_EM + (1<<15)) >> 16)); 443 #if 0 /* hb-ft works in no-hinting model */ 444 hb_font_set_ppem (font, 445 ft_face->size->metrics.x_ppem, 446 ft_face->size->metrics.y_ppem); 447 #endif 448 449 return font; 450 } 451 452 /** 453 * hb_ft_font_create_referenced: 454 * @ft_face: 455 * 456 * 457 * 458 * Return value: (transfer full): 459 * Since: 1.0 460 **/ 461 hb_font_t * 462 hb_ft_font_create_referenced (FT_Face ft_face) 463 { 464 FT_Reference_Face (ft_face); 465 return hb_ft_font_create (ft_face, (hb_destroy_func_t) FT_Done_Face); 466 } 467 468 469 /* Thread-safe, lock-free, FT_Library */ 470 471 static FT_Library ft_library; 472 473 #ifdef HB_USE_ATEXIT 474 static 475 void free_ft_library (void) 476 { 477 FT_Done_FreeType (ft_library); 478 } 479 #endif 480 481 static FT_Library 482 get_ft_library (void) 483 { 484 retry: 485 FT_Library library = (FT_Library) hb_atomic_ptr_get (&ft_library); 486 487 if (unlikely (!library)) 488 { 489 /* Not found; allocate one. */ 490 if (FT_Init_FreeType (&library)) 491 return NULL; 492 493 if (!hb_atomic_ptr_cmpexch (&ft_library, NULL, library)) { 494 FT_Done_FreeType (library); 495 goto retry; 496 } 497 498 #ifdef HB_USE_ATEXIT 499 atexit (free_ft_library); /* First person registers atexit() callback. */ 500 #endif 501 } 502 503 return library; 504 } 505 506 static void 507 _release_blob (FT_Face ft_face) 508 { 509 hb_blob_destroy ((hb_blob_t *) ft_face->generic.data); 510 } 511 512 void 513 hb_ft_font_set_funcs (hb_font_t *font) 514 { 515 hb_blob_t *blob = hb_face_reference_blob (font->face); 516 unsigned int blob_length; 517 const char *blob_data = hb_blob_get_data (blob, &blob_length); 518 if (unlikely (!blob_length)) 519 DEBUG_MSG (FT, font, "Font face has empty blob"); 520 521 FT_Face ft_face = NULL; 522 FT_Error err = FT_New_Memory_Face (get_ft_library (), 523 (const FT_Byte *) blob_data, 524 blob_length, 525 hb_face_get_index (font->face), 526 &ft_face); 527 528 if (unlikely (err)) { 529 hb_blob_destroy (blob); 530 DEBUG_MSG (FT, font, "Font face FT_New_Memory_Face() failed"); 531 return; 532 } 533 534 FT_Select_Charmap (ft_face, FT_ENCODING_UNICODE); 535 536 FT_Set_Char_Size (ft_face, 537 abs (font->x_scale), abs (font->y_scale), 538 0, 0); 539 #if 0 540 font->x_ppem * 72 * 64 / font->x_scale, 541 font->y_ppem * 72 * 64 / font->y_scale); 542 #endif 543 if (font->x_scale < 0 || font->y_scale < 0) 544 { 545 FT_Matrix matrix = { font->x_scale < 0 ? -1 : +1, 0, 546 0, font->y_scale < 0 ? -1 : +1}; 547 FT_Set_Transform (ft_face, &matrix, NULL); 548 } 549 550 ft_face->generic.data = blob; 551 ft_face->generic.finalizer = (FT_Generic_Finalizer) _release_blob; 552 553 hb_font_set_funcs (font, 554 _hb_ft_get_font_funcs (), 555 ft_face, 556 (hb_destroy_func_t) FT_Done_Face); 557 } 558 559 FT_Face 560 hb_ft_font_get_face (hb_font_t *font) 561 { 562 if (font->destroy == (hb_destroy_func_t) FT_Done_Face || 563 font->destroy == (hb_destroy_func_t) _do_nothing) 564 return (FT_Face) font->user_data; 565 566 return NULL; 567 } 568
