1 /**************************************************************************** 2 * 3 * ttdriver.c 4 * 5 * TrueType font driver implementation (body). 6 * 7 * Copyright 1996-2018 by 8 * David Turner, Robert Wilhelm, and Werner Lemberg. 9 * 10 * This file is part of the FreeType project, and may only be used, 11 * modified, and distributed under the terms of the FreeType project 12 * license, LICENSE.TXT. By continuing to use, modify, or distribute 13 * this file you indicate that you have read the license and 14 * understand and accept it fully. 15 * 16 */ 17 18 19 #include <ft2build.h> 20 #include FT_INTERNAL_DEBUG_H 21 #include FT_INTERNAL_STREAM_H 22 #include FT_INTERNAL_SFNT_H 23 #include FT_SERVICE_FONT_FORMAT_H 24 25 #ifdef TT_CONFIG_OPTION_GX_VAR_SUPPORT 26 #include FT_MULTIPLE_MASTERS_H 27 #include FT_SERVICE_MULTIPLE_MASTERS_H 28 #include FT_SERVICE_METRICS_VARIATIONS_H 29 #endif 30 31 #include FT_SERVICE_TRUETYPE_ENGINE_H 32 #include FT_SERVICE_TRUETYPE_GLYF_H 33 #include FT_SERVICE_PROPERTIES_H 34 #include FT_DRIVER_H 35 36 #include "ttdriver.h" 37 #include "ttgload.h" 38 #include "ttpload.h" 39 40 #ifdef TT_CONFIG_OPTION_GX_VAR_SUPPORT 41 #include "ttgxvar.h" 42 #endif 43 44 #include "tterrors.h" 45 46 47 /************************************************************************** 48 * 49 * The macro FT_COMPONENT is used in trace mode. It is an implicit 50 * parameter of the FT_TRACE() and FT_ERROR() macros, used to print/log 51 * messages during execution. 52 */ 53 #undef FT_COMPONENT 54 #define FT_COMPONENT trace_ttdriver 55 56 57 /* 58 * PROPERTY SERVICE 59 * 60 */ 61 static FT_Error tt_property_set(FT_Module module,const char * property_name,const void * value,FT_Bool value_is_string)62 tt_property_set( FT_Module module, /* TT_Driver */ 63 const char* property_name, 64 const void* value, 65 FT_Bool value_is_string ) 66 { 67 FT_Error error = FT_Err_Ok; 68 TT_Driver driver = (TT_Driver)module; 69 70 #ifndef FT_CONFIG_OPTION_ENVIRONMENT_PROPERTIES 71 FT_UNUSED( value_is_string ); 72 #endif 73 74 75 if ( !ft_strcmp( property_name, "interpreter-version" ) ) 76 { 77 FT_UInt interpreter_version; 78 79 80 #ifdef FT_CONFIG_OPTION_ENVIRONMENT_PROPERTIES 81 if ( value_is_string ) 82 { 83 const char* s = (const char*)value; 84 85 86 interpreter_version = (FT_UInt)ft_strtol( s, NULL, 10 ); 87 } 88 else 89 #endif 90 { 91 FT_UInt* iv = (FT_UInt*)value; 92 93 94 interpreter_version = *iv; 95 } 96 97 if ( interpreter_version == TT_INTERPRETER_VERSION_35 98 #ifdef TT_SUPPORT_SUBPIXEL_HINTING_INFINALITY 99 || interpreter_version == TT_INTERPRETER_VERSION_38 100 #endif 101 #ifdef TT_SUPPORT_SUBPIXEL_HINTING_MINIMAL 102 || interpreter_version == TT_INTERPRETER_VERSION_40 103 #endif 104 ) 105 driver->interpreter_version = interpreter_version; 106 else 107 error = FT_ERR( Unimplemented_Feature ); 108 109 return error; 110 } 111 112 FT_TRACE0(( "tt_property_set: missing property `%s'\n", 113 property_name )); 114 return FT_THROW( Missing_Property ); 115 } 116 117 118 static FT_Error tt_property_get(FT_Module module,const char * property_name,const void * value)119 tt_property_get( FT_Module module, /* TT_Driver */ 120 const char* property_name, 121 const void* value ) 122 { 123 FT_Error error = FT_Err_Ok; 124 TT_Driver driver = (TT_Driver)module; 125 126 FT_UInt interpreter_version = driver->interpreter_version; 127 128 129 if ( !ft_strcmp( property_name, "interpreter-version" ) ) 130 { 131 FT_UInt* val = (FT_UInt*)value; 132 133 134 *val = interpreter_version; 135 136 return error; 137 } 138 139 FT_TRACE0(( "tt_property_get: missing property `%s'\n", 140 property_name )); 141 return FT_THROW( Missing_Property ); 142 } 143 144 145 FT_DEFINE_SERVICE_PROPERTIESREC( 146 tt_service_properties, 147 148 (FT_Properties_SetFunc)tt_property_set, /* set_property */ 149 (FT_Properties_GetFunc)tt_property_get /* get_property */ 150 ) 151 152 153 /*************************************************************************/ 154 /*************************************************************************/ 155 /*************************************************************************/ 156 /**** ****/ 157 /**** ****/ 158 /**** F A C E S ****/ 159 /**** ****/ 160 /**** ****/ 161 /*************************************************************************/ 162 /*************************************************************************/ 163 /*************************************************************************/ 164 165 166 /************************************************************************** 167 * 168 * @Function: 169 * tt_get_kerning 170 * 171 * @Description: 172 * A driver method used to return the kerning vector between two 173 * glyphs of the same face. 174 * 175 * @Input: 176 * face :: 177 * A handle to the source face object. 178 * 179 * left_glyph :: 180 * The index of the left glyph in the kern pair. 181 * 182 * right_glyph :: 183 * The index of the right glyph in the kern pair. 184 * 185 * @Output: 186 * kerning :: 187 * The kerning vector. This is in font units for 188 * scalable formats, and in pixels for fixed-sizes 189 * formats. 190 * 191 * @Return: 192 * FreeType error code. 0 means success. 193 * 194 * @Note: 195 * Only horizontal layouts (left-to-right & right-to-left) are 196 * supported by this function. Other layouts, or more sophisticated 197 * kernings, are out of scope of this method (the basic driver 198 * interface is meant to be simple). 199 * 200 * They can be implemented by format-specific interfaces. 201 */ 202 static FT_Error tt_get_kerning(FT_Face ttface,FT_UInt left_glyph,FT_UInt right_glyph,FT_Vector * kerning)203 tt_get_kerning( FT_Face ttface, /* TT_Face */ 204 FT_UInt left_glyph, 205 FT_UInt right_glyph, 206 FT_Vector* kerning ) 207 { 208 TT_Face face = (TT_Face)ttface; 209 SFNT_Service sfnt = (SFNT_Service)face->sfnt; 210 211 212 kerning->x = 0; 213 kerning->y = 0; 214 215 if ( sfnt ) 216 kerning->x = sfnt->get_kerning( face, left_glyph, right_glyph ); 217 218 return 0; 219 } 220 221 222 static FT_Error tt_get_advances(FT_Face ttface,FT_UInt start,FT_UInt count,FT_Int32 flags,FT_Fixed * advances)223 tt_get_advances( FT_Face ttface, 224 FT_UInt start, 225 FT_UInt count, 226 FT_Int32 flags, 227 FT_Fixed *advances ) 228 { 229 FT_UInt nn; 230 TT_Face face = (TT_Face)ttface; 231 232 233 /* XXX: TODO: check for sbits */ 234 235 if ( flags & FT_LOAD_VERTICAL_LAYOUT ) 236 { 237 #ifdef TT_CONFIG_OPTION_GX_VAR_SUPPORT 238 /* no fast retrieval for blended MM fonts without VVAR table */ 239 if ( ( FT_IS_NAMED_INSTANCE( ttface ) || FT_IS_VARIATION( ttface ) ) && 240 !( face->variation_support & TT_FACE_FLAG_VAR_VADVANCE ) ) 241 return FT_THROW( Unimplemented_Feature ); 242 #endif 243 244 for ( nn = 0; nn < count; nn++ ) 245 { 246 FT_Short tsb; 247 FT_UShort ah; 248 249 250 /* since we don't need `tsb', we use zero for `yMax' parameter */ 251 TT_Get_VMetrics( face, start + nn, 0, &tsb, &ah ); 252 advances[nn] = ah; 253 } 254 } 255 else 256 { 257 #ifdef TT_CONFIG_OPTION_GX_VAR_SUPPORT 258 /* no fast retrieval for blended MM fonts without HVAR table */ 259 if ( ( FT_IS_NAMED_INSTANCE( ttface ) || FT_IS_VARIATION( ttface ) ) && 260 !( face->variation_support & TT_FACE_FLAG_VAR_HADVANCE ) ) 261 return FT_THROW( Unimplemented_Feature ); 262 #endif 263 264 for ( nn = 0; nn < count; nn++ ) 265 { 266 FT_Short lsb; 267 FT_UShort aw; 268 269 270 TT_Get_HMetrics( face, start + nn, &lsb, &aw ); 271 advances[nn] = aw; 272 } 273 } 274 275 return FT_Err_Ok; 276 } 277 278 279 /*************************************************************************/ 280 /*************************************************************************/ 281 /*************************************************************************/ 282 /**** ****/ 283 /**** ****/ 284 /**** S I Z E S ****/ 285 /**** ****/ 286 /**** ****/ 287 /*************************************************************************/ 288 /*************************************************************************/ 289 /*************************************************************************/ 290 291 292 #ifdef TT_CONFIG_OPTION_EMBEDDED_BITMAPS 293 294 static FT_Error tt_size_select(FT_Size size,FT_ULong strike_index)295 tt_size_select( FT_Size size, 296 FT_ULong strike_index ) 297 { 298 TT_Face ttface = (TT_Face)size->face; 299 TT_Size ttsize = (TT_Size)size; 300 FT_Error error = FT_Err_Ok; 301 302 303 ttsize->strike_index = strike_index; 304 305 if ( FT_IS_SCALABLE( size->face ) ) 306 { 307 /* use the scaled metrics, even when tt_size_reset fails */ 308 FT_Select_Metrics( size->face, strike_index ); 309 310 tt_size_reset( ttsize, 0 ); /* ignore return value */ 311 } 312 else 313 { 314 SFNT_Service sfnt = (SFNT_Service)ttface->sfnt; 315 FT_Size_Metrics* size_metrics = &size->metrics; 316 317 318 error = sfnt->load_strike_metrics( ttface, 319 strike_index, 320 size_metrics ); 321 if ( error ) 322 ttsize->strike_index = 0xFFFFFFFFUL; 323 } 324 325 return error; 326 } 327 328 #endif /* TT_CONFIG_OPTION_EMBEDDED_BITMAPS */ 329 330 331 static FT_Error tt_size_request(FT_Size size,FT_Size_Request req)332 tt_size_request( FT_Size size, 333 FT_Size_Request req ) 334 { 335 TT_Size ttsize = (TT_Size)size; 336 FT_Error error = FT_Err_Ok; 337 338 339 #ifdef TT_CONFIG_OPTION_EMBEDDED_BITMAPS 340 341 if ( FT_HAS_FIXED_SIZES( size->face ) ) 342 { 343 TT_Face ttface = (TT_Face)size->face; 344 SFNT_Service sfnt = (SFNT_Service)ttface->sfnt; 345 FT_ULong strike_index; 346 347 348 error = sfnt->set_sbit_strike( ttface, req, &strike_index ); 349 350 if ( error ) 351 ttsize->strike_index = 0xFFFFFFFFUL; 352 else 353 return tt_size_select( size, strike_index ); 354 } 355 356 #endif /* TT_CONFIG_OPTION_EMBEDDED_BITMAPS */ 357 358 FT_Request_Metrics( size->face, req ); 359 360 if ( FT_IS_SCALABLE( size->face ) ) 361 { 362 error = tt_size_reset( ttsize, 0 ); 363 364 #ifdef TT_USE_BYTECODE_INTERPRETER 365 /* for the `MPS' bytecode instruction we need the point size */ 366 if ( !error ) 367 { 368 FT_UInt resolution = 369 ttsize->metrics->x_ppem > ttsize->metrics->y_ppem 370 ? req->horiResolution 371 : req->vertResolution; 372 373 374 /* if we don't have a resolution value, assume 72dpi */ 375 if ( req->type == FT_SIZE_REQUEST_TYPE_SCALES || 376 !resolution ) 377 resolution = 72; 378 379 ttsize->point_size = FT_MulDiv( ttsize->ttmetrics.ppem, 380 64 * 72, 381 resolution ); 382 } 383 #endif 384 } 385 386 return error; 387 } 388 389 390 /************************************************************************** 391 * 392 * @Function: 393 * tt_glyph_load 394 * 395 * @Description: 396 * A driver method used to load a glyph within a given glyph slot. 397 * 398 * @Input: 399 * slot :: 400 * A handle to the target slot object where the glyph 401 * will be loaded. 402 * 403 * size :: 404 * A handle to the source face size at which the glyph 405 * must be scaled, loaded, etc. 406 * 407 * glyph_index :: 408 * The index of the glyph in the font file. 409 * 410 * load_flags :: 411 * A flag indicating what to load for this glyph. The 412 * FT_LOAD_XXX constants can be used to control the 413 * glyph loading process (e.g., whether the outline 414 * should be scaled, whether to load bitmaps or not, 415 * whether to hint the outline, etc). 416 * 417 * @Return: 418 * FreeType error code. 0 means success. 419 */ 420 static FT_Error tt_glyph_load(FT_GlyphSlot ttslot,FT_Size ttsize,FT_UInt glyph_index,FT_Int32 load_flags)421 tt_glyph_load( FT_GlyphSlot ttslot, /* TT_GlyphSlot */ 422 FT_Size ttsize, /* TT_Size */ 423 FT_UInt glyph_index, 424 FT_Int32 load_flags ) 425 { 426 TT_GlyphSlot slot = (TT_GlyphSlot)ttslot; 427 TT_Size size = (TT_Size)ttsize; 428 FT_Face face = ttslot->face; 429 FT_Error error; 430 431 432 if ( !slot ) 433 return FT_THROW( Invalid_Slot_Handle ); 434 435 if ( !size ) 436 return FT_THROW( Invalid_Size_Handle ); 437 438 if ( !face ) 439 return FT_THROW( Invalid_Face_Handle ); 440 441 #ifdef FT_CONFIG_OPTION_INCREMENTAL 442 if ( glyph_index >= (FT_UInt)face->num_glyphs && 443 !face->internal->incremental_interface ) 444 #else 445 if ( glyph_index >= (FT_UInt)face->num_glyphs ) 446 #endif 447 return FT_THROW( Invalid_Argument ); 448 449 if ( load_flags & FT_LOAD_NO_HINTING ) 450 { 451 /* both FT_LOAD_NO_HINTING and FT_LOAD_NO_AUTOHINT */ 452 /* are necessary to disable hinting for tricky fonts */ 453 454 if ( FT_IS_TRICKY( face ) ) 455 load_flags &= ~FT_LOAD_NO_HINTING; 456 457 if ( load_flags & FT_LOAD_NO_AUTOHINT ) 458 load_flags |= FT_LOAD_NO_HINTING; 459 } 460 461 if ( load_flags & ( FT_LOAD_NO_RECURSE | FT_LOAD_NO_SCALE ) ) 462 { 463 load_flags |= FT_LOAD_NO_BITMAP | FT_LOAD_NO_SCALE; 464 465 if ( !FT_IS_TRICKY( face ) ) 466 load_flags |= FT_LOAD_NO_HINTING; 467 } 468 469 /* use hinted metrics only if we load a glyph with hinting */ 470 size->metrics = ( load_flags & FT_LOAD_NO_HINTING ) 471 ? &ttsize->metrics 472 : &size->hinted_metrics; 473 474 /* now fill in the glyph slot with outline/bitmap/layered */ 475 error = TT_Load_Glyph( size, slot, glyph_index, load_flags ); 476 477 /* force drop-out mode to 2 - irrelevant now */ 478 /* slot->outline.dropout_mode = 2; */ 479 480 return error; 481 } 482 483 484 /*************************************************************************/ 485 /*************************************************************************/ 486 /*************************************************************************/ 487 /**** ****/ 488 /**** ****/ 489 /**** D R I V E R I N T E R F A C E ****/ 490 /**** ****/ 491 /**** ****/ 492 /*************************************************************************/ 493 /*************************************************************************/ 494 /*************************************************************************/ 495 496 #ifdef TT_CONFIG_OPTION_GX_VAR_SUPPORT 497 498 FT_DEFINE_SERVICE_MULTIMASTERSREC( 499 tt_service_gx_multi_masters, 500 501 (FT_Get_MM_Func) NULL, /* get_mm */ 502 (FT_Set_MM_Design_Func) NULL, /* set_mm_design */ 503 (FT_Set_MM_Blend_Func) TT_Set_MM_Blend, /* set_mm_blend */ 504 (FT_Get_MM_Blend_Func) TT_Get_MM_Blend, /* get_mm_blend */ 505 (FT_Get_MM_Var_Func) TT_Get_MM_Var, /* get_mm_var */ 506 (FT_Set_Var_Design_Func)TT_Set_Var_Design, /* set_var_design */ 507 (FT_Get_Var_Design_Func)TT_Get_Var_Design, /* get_var_design */ 508 (FT_Set_Instance_Func) TT_Set_Named_Instance, /* set_instance */ 509 510 (FT_Get_Var_Blend_Func) tt_get_var_blend, /* get_var_blend */ 511 (FT_Done_Blend_Func) tt_done_blend /* done_blend */ 512 ) 513 514 FT_DEFINE_SERVICE_METRICSVARIATIONSREC( 515 tt_service_metrics_variations, 516 517 (FT_HAdvance_Adjust_Func)tt_hadvance_adjust, /* hadvance_adjust */ 518 (FT_LSB_Adjust_Func) NULL, /* lsb_adjust */ 519 (FT_RSB_Adjust_Func) NULL, /* rsb_adjust */ 520 521 (FT_VAdvance_Adjust_Func)tt_vadvance_adjust, /* vadvance_adjust */ 522 (FT_TSB_Adjust_Func) NULL, /* tsb_adjust */ 523 (FT_BSB_Adjust_Func) NULL, /* bsb_adjust */ 524 (FT_VOrg_Adjust_Func) NULL, /* vorg_adjust */ 525 526 (FT_Metrics_Adjust_Func) tt_apply_mvar /* metrics_adjust */ 527 ) 528 529 #endif /* TT_CONFIG_OPTION_GX_VAR_SUPPORT */ 530 531 532 static const FT_Service_TrueTypeEngineRec tt_service_truetype_engine = 533 { 534 #ifdef TT_USE_BYTECODE_INTERPRETER 535 536 FT_TRUETYPE_ENGINE_TYPE_PATENTED 537 538 #else /* !TT_USE_BYTECODE_INTERPRETER */ 539 540 FT_TRUETYPE_ENGINE_TYPE_NONE 541 542 #endif /* TT_USE_BYTECODE_INTERPRETER */ 543 }; 544 545 546 FT_DEFINE_SERVICE_TTGLYFREC( 547 tt_service_truetype_glyf, 548 549 (TT_Glyf_GetLocationFunc)tt_face_get_location /* get_location */ 550 ) 551 552 553 #ifdef TT_CONFIG_OPTION_GX_VAR_SUPPORT 554 FT_DEFINE_SERVICEDESCREC6( 555 tt_services, 556 557 FT_SERVICE_ID_FONT_FORMAT, FT_FONT_FORMAT_TRUETYPE, 558 FT_SERVICE_ID_MULTI_MASTERS, &tt_service_gx_multi_masters, 559 FT_SERVICE_ID_METRICS_VARIATIONS, &tt_service_metrics_variations, 560 FT_SERVICE_ID_TRUETYPE_ENGINE, &tt_service_truetype_engine, 561 FT_SERVICE_ID_TT_GLYF, &tt_service_truetype_glyf, 562 FT_SERVICE_ID_PROPERTIES, &tt_service_properties ) 563 #else 564 FT_DEFINE_SERVICEDESCREC4( 565 tt_services, 566 567 FT_SERVICE_ID_FONT_FORMAT, FT_FONT_FORMAT_TRUETYPE, 568 FT_SERVICE_ID_TRUETYPE_ENGINE, &tt_service_truetype_engine, 569 FT_SERVICE_ID_TT_GLYF, &tt_service_truetype_glyf, 570 FT_SERVICE_ID_PROPERTIES, &tt_service_properties ) 571 #endif 572 573 FT_CALLBACK_DEF(FT_Module_Interface)574 FT_CALLBACK_DEF( FT_Module_Interface ) 575 tt_get_interface( FT_Module driver, /* TT_Driver */ 576 const char* tt_interface ) 577 { 578 FT_Library library; 579 FT_Module_Interface result; 580 FT_Module sfntd; 581 SFNT_Service sfnt; 582 583 584 result = ft_service_list_lookup( tt_services, tt_interface ); 585 if ( result ) 586 return result; 587 588 if ( !driver ) 589 return NULL; 590 library = driver->library; 591 if ( !library ) 592 return NULL; 593 594 /* only return the default interface from the SFNT module */ 595 sfntd = FT_Get_Module( library, "sfnt" ); 596 if ( sfntd ) 597 { 598 sfnt = (SFNT_Service)( sfntd->clazz->module_interface ); 599 if ( sfnt ) 600 return sfnt->get_interface( driver, tt_interface ); 601 } 602 603 return 0; 604 } 605 606 607 /* The FT_DriverInterface structure is defined in ftdriver.h. */ 608 609 #ifdef TT_USE_BYTECODE_INTERPRETER 610 #define TT_HINTER_FLAG FT_MODULE_DRIVER_HAS_HINTER 611 #else 612 #define TT_HINTER_FLAG 0 613 #endif 614 615 #ifdef TT_CONFIG_OPTION_EMBEDDED_BITMAPS 616 #define TT_SIZE_SELECT tt_size_select 617 #else 618 #define TT_SIZE_SELECT 0 619 #endif 620 621 FT_DEFINE_DRIVER( 622 tt_driver_class, 623 624 FT_MODULE_FONT_DRIVER | 625 FT_MODULE_DRIVER_SCALABLE | 626 TT_HINTER_FLAG, 627 628 sizeof ( TT_DriverRec ), 629 630 "truetype", /* driver name */ 631 0x10000L, /* driver version == 1.0 */ 632 0x20000L, /* driver requires FreeType 2.0 or above */ 633 634 NULL, /* module-specific interface */ 635 636 tt_driver_init, /* FT_Module_Constructor module_init */ 637 tt_driver_done, /* FT_Module_Destructor module_done */ 638 tt_get_interface, /* FT_Module_Requester get_interface */ 639 640 sizeof ( TT_FaceRec ), 641 sizeof ( TT_SizeRec ), 642 sizeof ( FT_GlyphSlotRec ), 643 644 tt_face_init, /* FT_Face_InitFunc init_face */ 645 tt_face_done, /* FT_Face_DoneFunc done_face */ 646 tt_size_init, /* FT_Size_InitFunc init_size */ 647 tt_size_done, /* FT_Size_DoneFunc done_size */ 648 tt_slot_init, /* FT_Slot_InitFunc init_slot */ 649 NULL, /* FT_Slot_DoneFunc done_slot */ 650 651 tt_glyph_load, /* FT_Slot_LoadFunc load_glyph */ 652 653 tt_get_kerning, /* FT_Face_GetKerningFunc get_kerning */ 654 NULL, /* FT_Face_AttachFunc attach_file */ 655 tt_get_advances, /* FT_Face_GetAdvancesFunc get_advances */ 656 657 tt_size_request, /* FT_Size_RequestFunc request_size */ 658 TT_SIZE_SELECT /* FT_Size_SelectFunc select_size */ 659 ) 660 661 662 /* END */ 663