1 /**************************************************************************** 2 * 3 * ttdriver.c 4 * 5 * TrueType font driver implementation (body). 6 * 7 * Copyright (C) 1996-2022 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 <freetype/internal/ftdebug.h> 20 #include <freetype/internal/ftstream.h> 21 #include <freetype/internal/sfnt.h> 22 #include <freetype/internal/services/svfntfmt.h> 23 24 #ifdef TT_CONFIG_OPTION_GX_VAR_SUPPORT 25 #include <freetype/ftmm.h> 26 #include <freetype/internal/services/svmm.h> 27 #include <freetype/internal/services/svmetric.h> 28 #endif 29 30 #include <freetype/internal/services/svtteng.h> 31 #include <freetype/internal/services/svttglyf.h> 32 #include <freetype/internal/services/svprop.h> 33 #include <freetype/ftdriver.h> 34 35 #include "ttdriver.h" 36 #include "ttgload.h" 37 #include "ttpload.h" 38 39 #ifdef TT_CONFIG_OPTION_GX_VAR_SUPPORT 40 #include "ttgxvar.h" 41 #endif 42 43 #include "tterrors.h" 44 45 46 /************************************************************************** 47 * 48 * The macro FT_COMPONENT is used in trace mode. It is an implicit 49 * parameter of the FT_TRACE() and FT_ERROR() macros, used to print/log 50 * messages during execution. 51 */ 52 #undef FT_COMPONENT 53 #define FT_COMPONENT ttdriver 54 55 56 /* 57 * PROPERTY SERVICE 58 * 59 */ 60 static FT_Error tt_property_set(FT_Module module,const char * property_name,const void * value,FT_Bool value_is_string)61 tt_property_set( FT_Module module, /* TT_Driver */ 62 const char* property_name, 63 const void* value, 64 FT_Bool value_is_string ) 65 { 66 FT_Error error = FT_Err_Ok; 67 TT_Driver driver = (TT_Driver)module; 68 69 #ifndef FT_CONFIG_OPTION_ENVIRONMENT_PROPERTIES 70 FT_UNUSED( value_is_string ); 71 #endif 72 73 74 if ( !ft_strcmp( property_name, "interpreter-version" ) ) 75 { 76 FT_UInt interpreter_version; 77 78 79 #ifdef FT_CONFIG_OPTION_ENVIRONMENT_PROPERTIES 80 if ( value_is_string ) 81 { 82 const char* s = (const char*)value; 83 84 85 interpreter_version = (FT_UInt)ft_strtol( s, NULL, 10 ); 86 } 87 else 88 #endif 89 { 90 FT_UInt* iv = (FT_UInt*)value; 91 92 93 interpreter_version = *iv; 94 } 95 96 if ( interpreter_version == TT_INTERPRETER_VERSION_35 97 #ifdef TT_SUPPORT_SUBPIXEL_HINTING_INFINALITY 98 || interpreter_version == TT_INTERPRETER_VERSION_38 99 #endif 100 #ifdef TT_SUPPORT_SUBPIXEL_HINTING_MINIMAL 101 || interpreter_version == TT_INTERPRETER_VERSION_40 102 #endif 103 ) 104 driver->interpreter_version = interpreter_version; 105 else 106 error = FT_ERR( Unimplemented_Feature ); 107 108 return error; 109 } 110 111 FT_TRACE2(( "tt_property_set: missing property `%s'\n", 112 property_name )); 113 return FT_THROW( Missing_Property ); 114 } 115 116 117 static FT_Error tt_property_get(FT_Module module,const char * property_name,const void * value)118 tt_property_get( FT_Module module, /* TT_Driver */ 119 const char* property_name, 120 const void* value ) 121 { 122 FT_Error error = FT_Err_Ok; 123 TT_Driver driver = (TT_Driver)module; 124 125 FT_UInt interpreter_version = driver->interpreter_version; 126 127 128 if ( !ft_strcmp( property_name, "interpreter-version" ) ) 129 { 130 FT_UInt* val = (FT_UInt*)value; 131 132 133 *val = interpreter_version; 134 135 return error; 136 } 137 138 FT_TRACE2(( "tt_property_get: missing property `%s'\n", 139 property_name )); 140 return FT_THROW( Missing_Property ); 141 } 142 143 144 FT_DEFINE_SERVICE_PROPERTIESREC( 145 tt_service_properties, 146 147 (FT_Properties_SetFunc)tt_property_set, /* set_property */ 148 (FT_Properties_GetFunc)tt_property_get /* get_property */ 149 ) 150 151 152 /*************************************************************************/ 153 /*************************************************************************/ 154 /*************************************************************************/ 155 /**** ****/ 156 /**** ****/ 157 /**** F A C E S ****/ 158 /**** ****/ 159 /**** ****/ 160 /*************************************************************************/ 161 /*************************************************************************/ 162 /*************************************************************************/ 163 164 165 /************************************************************************** 166 * 167 * @Function: 168 * tt_get_kerning 169 * 170 * @Description: 171 * A driver method used to return the kerning vector between two 172 * glyphs of the same face. 173 * 174 * @Input: 175 * face :: 176 * A handle to the source face object. 177 * 178 * left_glyph :: 179 * The index of the left glyph in the kern pair. 180 * 181 * right_glyph :: 182 * The index of the right glyph in the kern pair. 183 * 184 * @Output: 185 * kerning :: 186 * The kerning vector. This is in font units for 187 * scalable formats, and in pixels for fixed-sizes 188 * formats. 189 * 190 * @Return: 191 * FreeType error code. 0 means success. 192 * 193 * @Note: 194 * Only horizontal layouts (left-to-right & right-to-left) are 195 * supported by this function. Other layouts, or more sophisticated 196 * kernings, are out of scope of this method (the basic driver 197 * interface is meant to be simple). 198 * 199 * They can be implemented by format-specific interfaces. 200 */ 201 static FT_Error tt_get_kerning(FT_Face ttface,FT_UInt left_glyph,FT_UInt right_glyph,FT_Vector * kerning)202 tt_get_kerning( FT_Face ttface, /* TT_Face */ 203 FT_UInt left_glyph, 204 FT_UInt right_glyph, 205 FT_Vector* kerning ) 206 { 207 TT_Face face = (TT_Face)ttface; 208 SFNT_Service sfnt = (SFNT_Service)face->sfnt; 209 210 211 kerning->x = 0; 212 kerning->y = 0; 213 214 if ( sfnt ) 215 kerning->x = sfnt->get_kerning( face, left_glyph, right_glyph ); 216 217 return 0; 218 } 219 220 221 static FT_Error tt_get_advances(FT_Face ttface,FT_UInt start,FT_UInt count,FT_Int32 flags,FT_Fixed * advances)222 tt_get_advances( FT_Face ttface, 223 FT_UInt start, 224 FT_UInt count, 225 FT_Int32 flags, 226 FT_Fixed *advances ) 227 { 228 FT_UInt nn; 229 TT_Face face = (TT_Face)ttface; 230 231 232 /* XXX: TODO: check for sbits */ 233 234 if ( flags & FT_LOAD_VERTICAL_LAYOUT ) 235 { 236 #ifdef TT_CONFIG_OPTION_GX_VAR_SUPPORT 237 /* no fast retrieval for blended MM fonts without VVAR table */ 238 if ( ( FT_IS_NAMED_INSTANCE( ttface ) || FT_IS_VARIATION( ttface ) ) && 239 !( face->variation_support & TT_FACE_FLAG_VAR_VADVANCE ) ) 240 return FT_THROW( Unimplemented_Feature ); 241 #endif 242 243 for ( nn = 0; nn < count; nn++ ) 244 { 245 FT_Short tsb; 246 FT_UShort ah; 247 248 249 /* since we don't need `tsb', we use zero for `yMax' parameter */ 250 TT_Get_VMetrics( face, start + nn, 0, &tsb, &ah ); 251 advances[nn] = ah; 252 } 253 } 254 else 255 { 256 #ifdef TT_CONFIG_OPTION_GX_VAR_SUPPORT 257 /* no fast retrieval for blended MM fonts without HVAR table */ 258 if ( ( FT_IS_NAMED_INSTANCE( ttface ) || FT_IS_VARIATION( ttface ) ) && 259 !( face->variation_support & TT_FACE_FLAG_VAR_HADVANCE ) ) 260 return FT_THROW( Unimplemented_Feature ); 261 #endif 262 263 for ( nn = 0; nn < count; nn++ ) 264 { 265 FT_Short lsb; 266 FT_UShort aw; 267 268 269 TT_Get_HMetrics( face, start + nn, &lsb, &aw ); 270 advances[nn] = aw; 271 } 272 } 273 274 return FT_Err_Ok; 275 } 276 277 278 /*************************************************************************/ 279 /*************************************************************************/ 280 /*************************************************************************/ 281 /**** ****/ 282 /**** ****/ 283 /**** S I Z E S ****/ 284 /**** ****/ 285 /**** ****/ 286 /*************************************************************************/ 287 /*************************************************************************/ 288 /*************************************************************************/ 289 290 291 #ifdef TT_CONFIG_OPTION_EMBEDDED_BITMAPS 292 293 static FT_Error tt_size_select(FT_Size size,FT_ULong strike_index)294 tt_size_select( FT_Size size, 295 FT_ULong strike_index ) 296 { 297 TT_Face ttface = (TT_Face)size->face; 298 TT_Size ttsize = (TT_Size)size; 299 FT_Error error = FT_Err_Ok; 300 301 302 ttsize->strike_index = strike_index; 303 304 if ( FT_IS_SCALABLE( size->face ) ) 305 { 306 /* use the scaled metrics, even when tt_size_reset fails */ 307 FT_Select_Metrics( size->face, strike_index ); 308 309 tt_size_reset( ttsize, 0 ); /* ignore return value */ 310 } 311 else 312 { 313 SFNT_Service sfnt = (SFNT_Service)ttface->sfnt; 314 FT_Size_Metrics* size_metrics = &size->metrics; 315 316 317 error = sfnt->load_strike_metrics( ttface, 318 strike_index, 319 size_metrics ); 320 if ( error ) 321 ttsize->strike_index = 0xFFFFFFFFUL; 322 } 323 324 return error; 325 } 326 327 #endif /* TT_CONFIG_OPTION_EMBEDDED_BITMAPS */ 328 329 330 static FT_Error tt_size_request(FT_Size size,FT_Size_Request req)331 tt_size_request( FT_Size size, 332 FT_Size_Request req ) 333 { 334 TT_Size ttsize = (TT_Size)size; 335 FT_Error error = FT_Err_Ok; 336 337 338 #ifdef TT_CONFIG_OPTION_EMBEDDED_BITMAPS 339 340 if ( FT_HAS_FIXED_SIZES( size->face ) ) 341 { 342 TT_Face ttface = (TT_Face)size->face; 343 SFNT_Service sfnt = (SFNT_Service)ttface->sfnt; 344 FT_ULong strike_index; 345 346 347 error = sfnt->set_sbit_strike( ttface, req, &strike_index ); 348 349 if ( error ) 350 ttsize->strike_index = 0xFFFFFFFFUL; 351 else 352 return tt_size_select( size, strike_index ); 353 } 354 355 #endif /* TT_CONFIG_OPTION_EMBEDDED_BITMAPS */ 356 357 { 358 FT_Error err = FT_Request_Metrics( size->face, req ); 359 360 361 if ( err ) 362 { 363 error = err; 364 goto Exit; 365 } 366 } 367 368 if ( FT_IS_SCALABLE( size->face ) ) 369 { 370 error = tt_size_reset( ttsize, 0 ); 371 372 #ifdef TT_USE_BYTECODE_INTERPRETER 373 /* for the `MPS' bytecode instruction we need the point size */ 374 if ( !error ) 375 { 376 FT_UInt resolution = 377 ttsize->metrics->x_ppem > ttsize->metrics->y_ppem 378 ? req->horiResolution 379 : req->vertResolution; 380 381 382 /* if we don't have a resolution value, assume 72dpi */ 383 if ( req->type == FT_SIZE_REQUEST_TYPE_SCALES || 384 !resolution ) 385 resolution = 72; 386 387 ttsize->point_size = FT_MulDiv( ttsize->ttmetrics.ppem, 388 64 * 72, 389 resolution ); 390 } 391 #endif 392 } 393 394 Exit: 395 return error; 396 } 397 398 399 /************************************************************************** 400 * 401 * @Function: 402 * tt_glyph_load 403 * 404 * @Description: 405 * A driver method used to load a glyph within a given glyph slot. 406 * 407 * @Input: 408 * slot :: 409 * A handle to the target slot object where the glyph 410 * will be loaded. 411 * 412 * size :: 413 * A handle to the source face size at which the glyph 414 * must be scaled, loaded, etc. 415 * 416 * glyph_index :: 417 * The index of the glyph in the font file. 418 * 419 * load_flags :: 420 * A flag indicating what to load for this glyph. The 421 * FT_LOAD_XXX constants can be used to control the 422 * glyph loading process (e.g., whether the outline 423 * should be scaled, whether to load bitmaps or not, 424 * whether to hint the outline, etc). 425 * 426 * @Return: 427 * FreeType error code. 0 means success. 428 */ 429 static FT_Error tt_glyph_load(FT_GlyphSlot ttslot,FT_Size ttsize,FT_UInt glyph_index,FT_Int32 load_flags)430 tt_glyph_load( FT_GlyphSlot ttslot, /* TT_GlyphSlot */ 431 FT_Size ttsize, /* TT_Size */ 432 FT_UInt glyph_index, 433 FT_Int32 load_flags ) 434 { 435 TT_GlyphSlot slot = (TT_GlyphSlot)ttslot; 436 TT_Size size = (TT_Size)ttsize; 437 FT_Face face = ttslot->face; 438 FT_Error error; 439 440 441 if ( !slot ) 442 return FT_THROW( Invalid_Slot_Handle ); 443 444 if ( !size ) 445 return FT_THROW( Invalid_Size_Handle ); 446 447 if ( !face ) 448 return FT_THROW( Invalid_Face_Handle ); 449 450 #ifdef FT_CONFIG_OPTION_INCREMENTAL 451 if ( glyph_index >= (FT_UInt)face->num_glyphs && 452 !face->internal->incremental_interface ) 453 #else 454 if ( glyph_index >= (FT_UInt)face->num_glyphs ) 455 #endif 456 return FT_THROW( Invalid_Argument ); 457 458 if ( load_flags & FT_LOAD_NO_HINTING ) 459 { 460 /* both FT_LOAD_NO_HINTING and FT_LOAD_NO_AUTOHINT */ 461 /* are necessary to disable hinting for tricky fonts */ 462 463 if ( FT_IS_TRICKY( face ) ) 464 load_flags &= ~FT_LOAD_NO_HINTING; 465 466 if ( load_flags & FT_LOAD_NO_AUTOHINT ) 467 load_flags |= FT_LOAD_NO_HINTING; 468 } 469 470 if ( load_flags & ( FT_LOAD_NO_RECURSE | FT_LOAD_NO_SCALE ) ) 471 { 472 load_flags |= FT_LOAD_NO_BITMAP | FT_LOAD_NO_SCALE; 473 474 if ( !FT_IS_TRICKY( face ) ) 475 load_flags |= FT_LOAD_NO_HINTING; 476 } 477 478 /* use hinted metrics only if we load a glyph with hinting */ 479 size->metrics = ( load_flags & FT_LOAD_NO_HINTING ) 480 ? &ttsize->metrics 481 : &size->hinted_metrics; 482 483 /* now fill in the glyph slot with outline/bitmap/layered */ 484 error = TT_Load_Glyph( size, slot, glyph_index, load_flags ); 485 486 /* force drop-out mode to 2 - irrelevant now */ 487 /* slot->outline.dropout_mode = 2; */ 488 489 return error; 490 } 491 492 493 /*************************************************************************/ 494 /*************************************************************************/ 495 /*************************************************************************/ 496 /**** ****/ 497 /**** ****/ 498 /**** D R I V E R I N T E R F A C E ****/ 499 /**** ****/ 500 /**** ****/ 501 /*************************************************************************/ 502 /*************************************************************************/ 503 /*************************************************************************/ 504 505 #ifdef TT_CONFIG_OPTION_GX_VAR_SUPPORT 506 507 FT_DEFINE_SERVICE_MULTIMASTERSREC( 508 tt_service_gx_multi_masters, 509 510 (FT_Get_MM_Func) NULL, /* get_mm */ 511 (FT_Set_MM_Design_Func) NULL, /* set_mm_design */ 512 (FT_Set_MM_Blend_Func) TT_Set_MM_Blend, /* set_mm_blend */ 513 (FT_Get_MM_Blend_Func) TT_Get_MM_Blend, /* get_mm_blend */ 514 (FT_Get_MM_Var_Func) TT_Get_MM_Var, /* get_mm_var */ 515 (FT_Set_Var_Design_Func) TT_Set_Var_Design, /* set_var_design */ 516 (FT_Get_Var_Design_Func) TT_Get_Var_Design, /* get_var_design */ 517 (FT_Set_Instance_Func) TT_Set_Named_Instance, /* set_instance */ 518 (FT_Set_MM_WeightVector_Func)NULL, /* set_mm_weightvector */ 519 (FT_Get_MM_WeightVector_Func)NULL, /* get_mm_weightvector */ 520 521 (FT_Get_Var_Blend_Func) tt_get_var_blend, /* get_var_blend */ 522 (FT_Done_Blend_Func) tt_done_blend /* done_blend */ 523 ) 524 525 FT_DEFINE_SERVICE_METRICSVARIATIONSREC( 526 tt_service_metrics_variations, 527 528 (FT_HAdvance_Adjust_Func)tt_hadvance_adjust, /* hadvance_adjust */ 529 (FT_LSB_Adjust_Func) NULL, /* lsb_adjust */ 530 (FT_RSB_Adjust_Func) NULL, /* rsb_adjust */ 531 532 (FT_VAdvance_Adjust_Func)tt_vadvance_adjust, /* vadvance_adjust */ 533 (FT_TSB_Adjust_Func) NULL, /* tsb_adjust */ 534 (FT_BSB_Adjust_Func) NULL, /* bsb_adjust */ 535 (FT_VOrg_Adjust_Func) NULL, /* vorg_adjust */ 536 537 (FT_Metrics_Adjust_Func) tt_apply_mvar /* metrics_adjust */ 538 ) 539 540 #endif /* TT_CONFIG_OPTION_GX_VAR_SUPPORT */ 541 542 543 static const FT_Service_TrueTypeEngineRec tt_service_truetype_engine = 544 { 545 #ifdef TT_USE_BYTECODE_INTERPRETER 546 547 FT_TRUETYPE_ENGINE_TYPE_PATENTED 548 549 #else /* !TT_USE_BYTECODE_INTERPRETER */ 550 551 FT_TRUETYPE_ENGINE_TYPE_NONE 552 553 #endif /* TT_USE_BYTECODE_INTERPRETER */ 554 }; 555 556 557 FT_DEFINE_SERVICE_TTGLYFREC( 558 tt_service_truetype_glyf, 559 560 (TT_Glyf_GetLocationFunc)tt_face_get_location /* get_location */ 561 ) 562 563 564 #ifdef TT_CONFIG_OPTION_GX_VAR_SUPPORT 565 FT_DEFINE_SERVICEDESCREC6( 566 tt_services, 567 568 FT_SERVICE_ID_FONT_FORMAT, FT_FONT_FORMAT_TRUETYPE, 569 FT_SERVICE_ID_MULTI_MASTERS, &tt_service_gx_multi_masters, 570 FT_SERVICE_ID_METRICS_VARIATIONS, &tt_service_metrics_variations, 571 FT_SERVICE_ID_TRUETYPE_ENGINE, &tt_service_truetype_engine, 572 FT_SERVICE_ID_TT_GLYF, &tt_service_truetype_glyf, 573 FT_SERVICE_ID_PROPERTIES, &tt_service_properties ) 574 #else 575 FT_DEFINE_SERVICEDESCREC4( 576 tt_services, 577 578 FT_SERVICE_ID_FONT_FORMAT, FT_FONT_FORMAT_TRUETYPE, 579 FT_SERVICE_ID_TRUETYPE_ENGINE, &tt_service_truetype_engine, 580 FT_SERVICE_ID_TT_GLYF, &tt_service_truetype_glyf, 581 FT_SERVICE_ID_PROPERTIES, &tt_service_properties ) 582 #endif 583 584 FT_CALLBACK_DEF(FT_Module_Interface)585 FT_CALLBACK_DEF( FT_Module_Interface ) 586 tt_get_interface( FT_Module driver, /* TT_Driver */ 587 const char* tt_interface ) 588 { 589 FT_Library library; 590 FT_Module_Interface result; 591 FT_Module sfntd; 592 SFNT_Service sfnt; 593 594 595 result = ft_service_list_lookup( tt_services, tt_interface ); 596 if ( result ) 597 return result; 598 599 if ( !driver ) 600 return NULL; 601 library = driver->library; 602 if ( !library ) 603 return NULL; 604 605 /* only return the default interface from the SFNT module */ 606 sfntd = FT_Get_Module( library, "sfnt" ); 607 if ( sfntd ) 608 { 609 sfnt = (SFNT_Service)( sfntd->clazz->module_interface ); 610 if ( sfnt ) 611 return sfnt->get_interface( driver, tt_interface ); 612 } 613 614 return 0; 615 } 616 617 618 /* The FT_DriverInterface structure is defined in ftdriver.h. */ 619 620 #ifdef TT_USE_BYTECODE_INTERPRETER 621 #define TT_HINTER_FLAG FT_MODULE_DRIVER_HAS_HINTER 622 #else 623 #define TT_HINTER_FLAG 0 624 #endif 625 626 #ifdef TT_CONFIG_OPTION_EMBEDDED_BITMAPS 627 #define TT_SIZE_SELECT tt_size_select 628 #else 629 #define TT_SIZE_SELECT 0 630 #endif 631 632 FT_DEFINE_DRIVER( 633 tt_driver_class, 634 635 FT_MODULE_FONT_DRIVER | 636 FT_MODULE_DRIVER_SCALABLE | 637 TT_HINTER_FLAG, 638 639 sizeof ( TT_DriverRec ), 640 641 "truetype", /* driver name */ 642 0x10000L, /* driver version == 1.0 */ 643 0x20000L, /* driver requires FreeType 2.0 or above */ 644 645 NULL, /* module-specific interface */ 646 647 tt_driver_init, /* FT_Module_Constructor module_init */ 648 tt_driver_done, /* FT_Module_Destructor module_done */ 649 tt_get_interface, /* FT_Module_Requester get_interface */ 650 651 sizeof ( TT_FaceRec ), 652 sizeof ( TT_SizeRec ), 653 sizeof ( FT_GlyphSlotRec ), 654 655 tt_face_init, /* FT_Face_InitFunc init_face */ 656 tt_face_done, /* FT_Face_DoneFunc done_face */ 657 tt_size_init, /* FT_Size_InitFunc init_size */ 658 tt_size_done, /* FT_Size_DoneFunc done_size */ 659 tt_slot_init, /* FT_Slot_InitFunc init_slot */ 660 NULL, /* FT_Slot_DoneFunc done_slot */ 661 662 tt_glyph_load, /* FT_Slot_LoadFunc load_glyph */ 663 664 tt_get_kerning, /* FT_Face_GetKerningFunc get_kerning */ 665 NULL, /* FT_Face_AttachFunc attach_file */ 666 tt_get_advances, /* FT_Face_GetAdvancesFunc get_advances */ 667 668 tt_size_request, /* FT_Size_RequestFunc request_size */ 669 TT_SIZE_SELECT /* FT_Size_SelectFunc select_size */ 670 ) 671 672 673 /* END */ 674