1 /***************************************************************************/ 2 /* */ 3 /* sfnt.h */ 4 /* */ 5 /* High-level `sfnt' driver interface (specification). */ 6 /* */ 7 /* Copyright 1996-2001, 2002 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 #ifndef __SFNT_H__ 20 #define __SFNT_H__ 21 22 23 #include <ft2build.h> 24 #include FT_INTERNAL_DRIVER_H 25 #include FT_INTERNAL_TRUETYPE_TYPES_H 26 27 28 FT_BEGIN_HEADER 29 30 31 /*************************************************************************/ 32 /* */ 33 /* <FuncType> */ 34 /* TT_Init_Face_Func */ 35 /* */ 36 /* <Description> */ 37 /* First part of the SFNT face object initialization. This will find */ 38 /* the face in a SFNT file or collection, and load its format tag in */ 39 /* face->format_tag. */ 40 /* */ 41 /* <Input> */ 42 /* stream :: The input stream. */ 43 /* */ 44 /* face :: A handle to the target face object. */ 45 /* */ 46 /* face_index :: The index of the TrueType font, if we are opening a */ 47 /* collection. */ 48 /* */ 49 /* num_params :: The number of additional parameters. */ 50 /* */ 51 /* params :: Optional additional parameters. */ 52 /* */ 53 /* <Return> */ 54 /* FreeType error code. 0 means success. */ 55 /* */ 56 /* <Note> */ 57 /* The stream cursor must be at the font file's origin. */ 58 /* */ 59 /* This function recognizes fonts embedded in a `TrueType */ 60 /* collection'. */ 61 /* */ 62 /* Once the format tag has been validated by the font driver, it */ 63 /* should then call the TT_Load_Face_Func() callback to read the rest */ 64 /* of the SFNT tables in the object. */ 65 /* */ 66 typedef FT_Error 67 (*TT_Init_Face_Func)( FT_Stream stream, 68 TT_Face face, 69 FT_Int face_index, 70 FT_Int num_params, 71 FT_Parameter* params ); 72 73 74 /*************************************************************************/ 75 /* */ 76 /* <FuncType> */ 77 /* TT_Load_Face_Func */ 78 /* */ 79 /* <Description> */ 80 /* Second part of the SFNT face object initialization. This will */ 81 /* load the common SFNT tables (head, OS/2, maxp, metrics, etc.) in */ 82 /* the face object. */ 83 /* */ 84 /* <Input> */ 85 /* stream :: The input stream. */ 86 /* */ 87 /* face :: A handle to the target face object. */ 88 /* */ 89 /* face_index :: The index of the TrueType font, if we are opening a */ 90 /* collection. */ 91 /* */ 92 /* num_params :: The number of additional parameters. */ 93 /* */ 94 /* params :: Optional additional parameters. */ 95 /* */ 96 /* <Return> */ 97 /* FreeType error code. 0 means success. */ 98 /* */ 99 /* <Note> */ 100 /* This function must be called after TT_Init_Face_Func(). */ 101 /* */ 102 typedef FT_Error 103 (*TT_Load_Face_Func)( FT_Stream stream, 104 TT_Face face, 105 FT_Int face_index, 106 FT_Int num_params, 107 FT_Parameter* params ); 108 109 110 /*************************************************************************/ 111 /* */ 112 /* <FuncType> */ 113 /* TT_Done_Face_Func */ 114 /* */ 115 /* <Description> */ 116 /* A callback used to delete the common SFNT data from a face. */ 117 /* */ 118 /* <Input> */ 119 /* face :: A handle to the target face object. */ 120 /* */ 121 /* <Note> */ 122 /* This function does NOT destroy the face object. */ 123 /* */ 124 typedef void 125 (*TT_Done_Face_Func)( TT_Face face ); 126 127 128 typedef FT_Module_Interface 129 (*SFNT_Get_Interface_Func)( FT_Module module, 130 const char* func_interface ); 131 132 133 /*************************************************************************/ 134 /* */ 135 /* <FuncType> */ 136 /* TT_Load_SFNT_HeaderRec_Func */ 137 /* */ 138 /* <Description> */ 139 /* Loads the header of a SFNT font file. Supports collections. */ 140 /* */ 141 /* <Input> */ 142 /* face :: A handle to the target face object. */ 143 /* */ 144 /* stream :: The input stream. */ 145 /* */ 146 /* face_index :: The index of the TrueType font, if we are opening a */ 147 /* collection. */ 148 /* */ 149 /* <Output> */ 150 /* sfnt :: The SFNT header. */ 151 /* */ 152 /* <Return> */ 153 /* FreeType error code. 0 means success. */ 154 /* */ 155 /* <Note> */ 156 /* The stream cursor must be at the font file's origin. */ 157 /* */ 158 /* This function recognizes fonts embedded in a `TrueType */ 159 /* collection'. */ 160 /* */ 161 /* This function checks that the header is valid by looking at the */ 162 /* values of `search_range', `entry_selector', and `range_shift'. */ 163 /* */ 164 typedef FT_Error 165 (*TT_Load_SFNT_HeaderRec_Func)( TT_Face face, 166 FT_Stream stream, 167 FT_Long face_index, 168 SFNT_Header sfnt ); 169 170 171 /*************************************************************************/ 172 /* */ 173 /* <FuncType> */ 174 /* TT_Load_Directory_Func */ 175 /* */ 176 /* <Description> */ 177 /* Loads the table directory into a face object. */ 178 /* */ 179 /* <Input> */ 180 /* face :: A handle to the target face object. */ 181 /* */ 182 /* stream :: The input stream. */ 183 /* */ 184 /* sfnt :: The SFNT header. */ 185 /* */ 186 /* <Return> */ 187 /* FreeType error code. 0 means success. */ 188 /* */ 189 /* <Note> */ 190 /* The stream cursor must be on the first byte after the 4-byte font */ 191 /* format tag. This is the case just after a call to */ 192 /* TT_Load_Format_Tag(). */ 193 /* */ 194 typedef FT_Error 195 (*TT_Load_Directory_Func)( TT_Face face, 196 FT_Stream stream, 197 SFNT_Header sfnt ); 198 199 200 /*************************************************************************/ 201 /* */ 202 /* <FuncType> */ 203 /* TT_Load_Any_Func */ 204 /* */ 205 /* <Description> */ 206 /* Loads any font table into client memory. */ 207 /* */ 208 /* <Input> */ 209 /* face :: The face object to look for. */ 210 /* */ 211 /* tag :: The tag of table to load. Use the value 0 if you want */ 212 /* to access the whole font file, else set this parameter */ 213 /* to a valid TrueType table tag that you can forge with */ 214 /* the MAKE_TT_TAG macro. */ 215 /* */ 216 /* offset :: The starting offset in the table (or the file if */ 217 /* tag == 0). */ 218 /* */ 219 /* length :: The address of the decision variable: */ 220 /* */ 221 /* If length == NULL: */ 222 /* Loads the whole table. Returns an error if */ 223 /* `offset' == 0! */ 224 /* */ 225 /* If *length == 0: */ 226 /* Exits immediately; returning the length of the given */ 227 /* table or of the font file, depending on the value of */ 228 /* `tag'. */ 229 /* */ 230 /* If *length != 0: */ 231 /* Loads the next `length' bytes of table or font, */ 232 /* starting at offset `offset' (in table or font too). */ 233 /* */ 234 /* <Output> */ 235 /* buffer :: The address of target buffer. */ 236 /* */ 237 /* <Return> */ 238 /* TrueType error code. 0 means success. */ 239 /* */ 240 typedef FT_Error 241 (*TT_Load_Any_Func)( TT_Face face, 242 FT_ULong tag, 243 FT_Long offset, 244 FT_Byte *buffer, 245 FT_ULong* length ); 246 247 248 /*************************************************************************/ 249 /* */ 250 /* <FuncType> */ 251 /* TT_Load_SBit_Image_Func */ 252 /* */ 253 /* <Description> */ 254 /* Loads a given glyph sbit image from the font resource. This also */ 255 /* returns its metrics. */ 256 /* */ 257 /* <Input> */ 258 /* face :: The target face object. */ 259 /* */ 260 /* x_ppem :: The horizontal resolution in points per EM. */ 261 /* */ 262 /* y_ppem :: The vertical resolution in points per EM. */ 263 /* */ 264 /* glyph_index :: The current glyph index. */ 265 /* */ 266 /* stream :: The input stream. */ 267 /* */ 268 /* <Output> */ 269 /* amap :: The target pixmap. */ 270 /* */ 271 /* ametrics :: A big sbit metrics structure for the glyph image. */ 272 /* */ 273 /* <Return> */ 274 /* FreeType error code. 0 means success. Returns an error if no */ 275 /* glyph sbit exists for the index. */ 276 /* */ 277 /* <Note> */ 278 /* The `map.buffer' field is always freed before the glyph is loaded. */ 279 /* */ 280 typedef FT_Error 281 (*TT_Load_SBit_Image_Func)( TT_Face face, 282 FT_ULong strike_index, 283 FT_UInt glyph_index, 284 FT_UInt load_flags, 285 FT_Stream stream, 286 FT_Bitmap *amap, 287 TT_SBit_MetricsRec *ametrics ); 288 289 290 /*************************************************************************/ 291 /* */ 292 /* <FuncType> */ 293 /* TT_Set_SBit_Strike_Func */ 294 /* */ 295 /* <Description> */ 296 /* Selects an sbit strike for given horizontal and vertical ppem */ 297 /* values. */ 298 /* */ 299 /* <Input> */ 300 /* face :: The target face object. */ 301 /* */ 302 /* x_ppem :: The horizontal resolution in points per EM. */ 303 /* */ 304 /* y_ppem :: The vertical resolution in points per EM. */ 305 /* */ 306 /* <Output> */ 307 /* astrike_index :: The index of the sbit strike. */ 308 /* */ 309 /* <Return> */ 310 /* FreeType error code. 0 means success. Returns an error if no */ 311 /* sbit strike exists for the selected ppem values. */ 312 /* */ 313 typedef FT_Error 314 (*TT_Set_SBit_Strike_Func)( TT_Face face, 315 FT_Int x_ppem, 316 FT_Int y_ppem, 317 FT_ULong *astrike_index ); 318 319 320 /*************************************************************************/ 321 /* */ 322 /* <FuncType> */ 323 /* TT_Get_PS_Name_Func */ 324 /* */ 325 /* <Description> */ 326 /* Gets the PostScript glyph name of a glyph. */ 327 /* */ 328 /* <Input> */ 329 /* idx :: The glyph index. */ 330 /* */ 331 /* PSname :: The address of a string pointer. Will be NULL in case */ 332 /* of error, otherwise it is a pointer to the glyph name. */ 333 /* */ 334 /* You must not modify the returned string! */ 335 /* */ 336 /* <Output> */ 337 /* FreeType error code. 0 means success. */ 338 /* */ 339 typedef FT_Error 340 (*TT_Get_PS_Name_Func)( TT_Face face, 341 FT_UInt idx, 342 FT_String** PSname ); 343 344 345 /*************************************************************************/ 346 /* */ 347 /* <FuncType> */ 348 /* TT_Load_Metrics_Func */ 349 /* */ 350 /* <Description> */ 351 /* Loads the horizontal or vertical header in a face object. */ 352 /* */ 353 /* <Input> */ 354 /* face :: A handle to the target face object. */ 355 /* */ 356 /* stream :: The input stream. */ 357 /* */ 358 /* vertical :: A boolean flag. If set, load vertical metrics. */ 359 /* */ 360 /* <Return> */ 361 /* FreeType error code. 0 means success. */ 362 /* */ 363 typedef FT_Error 364 (*TT_Load_Metrics_Func)( TT_Face face, 365 FT_Stream stream, 366 FT_Bool vertical ); 367 368 369 /*************************************************************************/ 370 /* */ 371 /* <FuncType> */ 372 /* TT_CharMap_Load_Func */ 373 /* */ 374 /* <Description> */ 375 /* Loads a given TrueType character map into memory. */ 376 /* */ 377 /* <Input> */ 378 /* face :: A handle to the parent face object. */ 379 /* */ 380 /* stream :: A handle to the current stream object. */ 381 /* */ 382 /* <InOut> */ 383 /* cmap :: A pointer to a cmap object. */ 384 /* */ 385 /* <Return> */ 386 /* FreeType error code. 0 means success. */ 387 /* */ 388 /* <Note> */ 389 /* The function assumes that the stream is already in use (i.e., */ 390 /* opened). In case of error, all partially allocated tables are */ 391 /* released. */ 392 /* */ 393 typedef FT_Error 394 (*TT_CharMap_Load_Func)( TT_Face face, 395 TT_CMapTable cmap, 396 FT_Stream input ); 397 398 399 /*************************************************************************/ 400 /* */ 401 /* <FuncType> */ 402 /* TT_CharMap_Free_Func */ 403 /* */ 404 /* <Description> */ 405 /* Destroys a character mapping table. */ 406 /* */ 407 /* <Input> */ 408 /* face :: A handle to the parent face object. */ 409 /* */ 410 /* cmap :: A handle to a cmap object. */ 411 /* */ 412 /* <Return> */ 413 /* FreeType error code. 0 means success. */ 414 /* */ 415 typedef FT_Error 416 (*TT_CharMap_Free_Func)( TT_Face face, 417 TT_CMapTable cmap ); 418 419 420 /*************************************************************************/ 421 /* */ 422 /* <FuncType> */ 423 /* TT_Load_Table_Func */ 424 /* */ 425 /* <Description> */ 426 /* Loads a given TrueType table. */ 427 /* */ 428 /* <Input> */ 429 /* face :: A handle to the target face object. */ 430 /* */ 431 /* stream :: The input stream. */ 432 /* */ 433 /* <Return> */ 434 /* FreeType error code. 0 means success. */ 435 /* */ 436 /* <Note> */ 437 /* The function will use `face->goto_table' to seek the stream to */ 438 /* the start of the table. */ 439 /* */ 440 typedef FT_Error 441 (*TT_Load_Table_Func)( TT_Face face, 442 FT_Stream stream ); 443 444 445 /*************************************************************************/ 446 /* */ 447 /* <FuncType> */ 448 /* TT_Free_Table_Func */ 449 /* */ 450 /* <Description> */ 451 /* Frees a given TrueType table. */ 452 /* */ 453 /* <Input> */ 454 /* face :: A handle to the target face object. */ 455 /* */ 456 typedef void 457 (*TT_Free_Table_Func)( TT_Face face ); 458 459 460 /*************************************************************************/ 461 /* */ 462 /* <Struct> */ 463 /* SFNT_Interface */ 464 /* */ 465 /* <Description> */ 466 /* This structure holds pointers to the functions used to load and */ 467 /* free the basic tables that are required in a `sfnt' font file. */ 468 /* */ 469 /* <Fields> */ 470 /* Check the various xxx_Func() descriptions for details. */ 471 /* */ 472 typedef struct SFNT_Interface_ 473 { 474 TT_Loader_GotoTableFunc goto_table; 475 476 TT_Init_Face_Func init_face; 477 TT_Load_Face_Func load_face; 478 TT_Done_Face_Func done_face; 479 SFNT_Get_Interface_Func get_interface; 480 481 TT_Load_Any_Func load_any; 482 TT_Load_SFNT_HeaderRec_Func load_sfnt_header; 483 TT_Load_Directory_Func load_directory; 484 485 /* these functions are called by `load_face' but they can also */ 486 /* be called from external modules, if there is a need to do so */ 487 TT_Load_Table_Func load_header; 488 TT_Load_Metrics_Func load_metrics; 489 TT_Load_Table_Func load_charmaps; 490 TT_Load_Table_Func load_max_profile; 491 TT_Load_Table_Func load_os2; 492 TT_Load_Table_Func load_psnames; 493 494 TT_Load_Table_Func load_names; 495 TT_Free_Table_Func free_names; 496 497 /* optional tables */ 498 TT_Load_Table_Func load_hdmx; 499 TT_Free_Table_Func free_hdmx; 500 501 TT_Load_Table_Func load_kerning; 502 TT_Load_Table_Func load_gasp; 503 TT_Load_Table_Func load_pclt; 504 505 /* see `ttload.h' */ 506 TT_Load_Table_Func load_bitmap_header; 507 508 /* see `ttsbit.h' */ 509 TT_Set_SBit_Strike_Func set_sbit_strike; 510 TT_Load_Table_Func load_sbits; 511 TT_Load_SBit_Image_Func load_sbit_image; 512 TT_Free_Table_Func free_sbits; 513 514 /* see `ttpost.h' */ 515 TT_Get_PS_Name_Func get_psname; 516 TT_Free_Table_Func free_psnames; 517 518 /* see `ttcmap.h' */ 519 TT_CharMap_Load_Func load_charmap; 520 TT_CharMap_Free_Func free_charmap; 521 522 } SFNT_Interface; 523 524 525 /* transitional */ 526 typedef SFNT_Interface* SFNT_Service; 527 528 529 FT_END_HEADER 530 531 #endif /* __SFNT_H__ */ 532 533 534 /* END */ 535