1 /***************************************************************************/ 2 /* */ 3 /* ttobjs.h */ 4 /* */ 5 /* Objects manager (specification). */ 6 /* */ 7 /* Copyright 1996-2015 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 __TTOBJS_H__ 20 #define __TTOBJS_H__ 21 22 23 #include <ft2build.h> 24 #include FT_INTERNAL_OBJECTS_H 25 #include FT_INTERNAL_TRUETYPE_TYPES_H 26 27 28 FT_BEGIN_HEADER 29 30 31 /*************************************************************************/ 32 /* */ 33 /* <Type> */ 34 /* TT_Driver */ 35 /* */ 36 /* <Description> */ 37 /* A handle to a TrueType driver object. */ 38 /* */ 39 typedef struct TT_DriverRec_* TT_Driver; 40 41 42 /*************************************************************************/ 43 /* */ 44 /* <Type> */ 45 /* TT_GlyphSlot */ 46 /* */ 47 /* <Description> */ 48 /* A handle to a TrueType glyph slot object. */ 49 /* */ 50 /* <Note> */ 51 /* This is a direct typedef of FT_GlyphSlot, as there is nothing */ 52 /* specific about the TrueType glyph slot. */ 53 /* */ 54 typedef FT_GlyphSlot TT_GlyphSlot; 55 56 57 /*************************************************************************/ 58 /* */ 59 /* <Struct> */ 60 /* TT_GraphicsState */ 61 /* */ 62 /* <Description> */ 63 /* The TrueType graphics state used during bytecode interpretation. */ 64 /* */ 65 typedef struct TT_GraphicsState_ 66 { 67 FT_UShort rp0; 68 FT_UShort rp1; 69 FT_UShort rp2; 70 71 FT_UnitVector dualVector; 72 FT_UnitVector projVector; 73 FT_UnitVector freeVector; 74 75 #ifdef TT_CONFIG_OPTION_UNPATENTED_HINTING 76 FT_Bool both_x_axis; 77 #endif 78 79 FT_Long loop; 80 FT_F26Dot6 minimum_distance; 81 FT_Int round_state; 82 83 FT_Bool auto_flip; 84 FT_F26Dot6 control_value_cutin; 85 FT_F26Dot6 single_width_cutin; 86 FT_F26Dot6 single_width_value; 87 FT_UShort delta_base; 88 FT_UShort delta_shift; 89 90 FT_Byte instruct_control; 91 /* According to Greg Hitchcock from Microsoft, the `scan_control' */ 92 /* variable as documented in the TrueType specification is a 32-bit */ 93 /* integer; the high-word part holds the SCANTYPE value, the low-word */ 94 /* part the SCANCTRL value. We separate it into two fields. */ 95 FT_Bool scan_control; 96 FT_Int scan_type; 97 98 FT_UShort gep0; 99 FT_UShort gep1; 100 FT_UShort gep2; 101 102 } TT_GraphicsState; 103 104 105 #ifdef TT_USE_BYTECODE_INTERPRETER 106 107 FT_LOCAL( void ) 108 tt_glyphzone_done( TT_GlyphZone zone ); 109 110 FT_LOCAL( FT_Error ) 111 tt_glyphzone_new( FT_Memory memory, 112 FT_UShort maxPoints, 113 FT_Short maxContours, 114 TT_GlyphZone zone ); 115 116 #endif /* TT_USE_BYTECODE_INTERPRETER */ 117 118 119 120 /*************************************************************************/ 121 /* */ 122 /* EXECUTION SUBTABLES */ 123 /* */ 124 /* These sub-tables relate to instruction execution. */ 125 /* */ 126 /*************************************************************************/ 127 128 129 #define TT_MAX_CODE_RANGES 3 130 131 132 /*************************************************************************/ 133 /* */ 134 /* There can only be 3 active code ranges at once: */ 135 /* - the Font Program */ 136 /* - the CVT Program */ 137 /* - a glyph's instructions set */ 138 /* */ 139 typedef enum TT_CodeRange_Tag_ 140 { 141 tt_coderange_none = 0, 142 tt_coderange_font, 143 tt_coderange_cvt, 144 tt_coderange_glyph 145 146 } TT_CodeRange_Tag; 147 148 149 typedef struct TT_CodeRange_ 150 { 151 FT_Byte* base; 152 FT_Long size; 153 154 } TT_CodeRange; 155 156 typedef TT_CodeRange TT_CodeRangeTable[TT_MAX_CODE_RANGES]; 157 158 159 /*************************************************************************/ 160 /* */ 161 /* Defines a function/instruction definition record. */ 162 /* */ 163 typedef struct TT_DefRecord_ 164 { 165 FT_Int range; /* in which code range is it located? */ 166 FT_Long start; /* where does it start? */ 167 FT_Long end; /* where does it end? */ 168 FT_UInt opc; /* function #, or instruction code */ 169 FT_Bool active; /* is it active? */ 170 FT_Bool inline_delta; /* is function that defines inline delta? */ 171 FT_ULong sph_fdef_flags; /* flags to identify special functions */ 172 173 } TT_DefRecord, *TT_DefArray; 174 175 176 /*************************************************************************/ 177 /* */ 178 /* Subglyph transformation record. */ 179 /* */ 180 typedef struct TT_Transform_ 181 { 182 FT_Fixed xx, xy; /* transformation matrix coefficients */ 183 FT_Fixed yx, yy; 184 FT_F26Dot6 ox, oy; /* offsets */ 185 186 } TT_Transform; 187 188 189 /*************************************************************************/ 190 /* */ 191 /* A note regarding non-squared pixels: */ 192 /* */ 193 /* (This text will probably go into some docs at some time; for now, it */ 194 /* is kept here to explain some definitions in the TT_Size_Metrics */ 195 /* record). */ 196 /* */ 197 /* The CVT is a one-dimensional array containing values that control */ 198 /* certain important characteristics in a font, like the height of all */ 199 /* capitals, all lowercase letter, default spacing or stem width/height. */ 200 /* */ 201 /* These values are found in FUnits in the font file, and must be scaled */ 202 /* to pixel coordinates before being used by the CVT and glyph programs. */ 203 /* Unfortunately, when using distinct x and y resolutions (or distinct x */ 204 /* and y pointsizes), there are two possible scalings. */ 205 /* */ 206 /* A first try was to implement a `lazy' scheme where all values were */ 207 /* scaled when first used. However, while some values are always used */ 208 /* in the same direction, some others are used under many different */ 209 /* circumstances and orientations. */ 210 /* */ 211 /* I have found a simpler way to do the same, and it even seems to work */ 212 /* in most of the cases: */ 213 /* */ 214 /* - All CVT values are scaled to the maximum ppem size. */ 215 /* */ 216 /* - When performing a read or write in the CVT, a ratio factor is used */ 217 /* to perform adequate scaling. Example: */ 218 /* */ 219 /* x_ppem = 14 */ 220 /* y_ppem = 10 */ 221 /* */ 222 /* We choose ppem = x_ppem = 14 as the CVT scaling size. All cvt */ 223 /* entries are scaled to it. */ 224 /* */ 225 /* x_ratio = 1.0 */ 226 /* y_ratio = y_ppem/ppem (< 1.0) */ 227 /* */ 228 /* We compute the current ratio like: */ 229 /* */ 230 /* - If projVector is horizontal, */ 231 /* ratio = x_ratio = 1.0 */ 232 /* */ 233 /* - if projVector is vertical, */ 234 /* ratio = y_ratio */ 235 /* */ 236 /* - else, */ 237 /* ratio = sqrt( (proj.x * x_ratio) ^ 2 + (proj.y * y_ratio) ^ 2 ) */ 238 /* */ 239 /* Reading a cvt value returns */ 240 /* ratio * cvt[index] */ 241 /* */ 242 /* Writing a cvt value in pixels: */ 243 /* cvt[index] / ratio */ 244 /* */ 245 /* The current ppem is simply */ 246 /* ratio * ppem */ 247 /* */ 248 /*************************************************************************/ 249 250 251 /*************************************************************************/ 252 /* */ 253 /* Metrics used by the TrueType size and context objects. */ 254 /* */ 255 typedef struct TT_Size_Metrics_ 256 { 257 /* for non-square pixels */ 258 FT_Long x_ratio; 259 FT_Long y_ratio; 260 261 FT_UShort ppem; /* maximum ppem size */ 262 FT_Long ratio; /* current ratio */ 263 FT_Fixed scale; 264 265 FT_F26Dot6 compensations[4]; /* device-specific compensations */ 266 267 FT_Bool valid; 268 269 FT_Bool rotated; /* `is the glyph rotated?'-flag */ 270 FT_Bool stretched; /* `is the glyph stretched?'-flag */ 271 272 } TT_Size_Metrics; 273 274 275 /*************************************************************************/ 276 /* */ 277 /* TrueType size class. */ 278 /* */ 279 typedef struct TT_SizeRec_ 280 { 281 FT_SizeRec root; 282 283 /* we have our own copy of metrics so that we can modify */ 284 /* it without affecting auto-hinting (when used) */ 285 FT_Size_Metrics metrics; 286 287 TT_Size_Metrics ttmetrics; 288 289 FT_ULong strike_index; /* 0xFFFFFFFF to indicate invalid */ 290 291 #ifdef TT_USE_BYTECODE_INTERPRETER 292 293 FT_UInt num_function_defs; /* number of function definitions */ 294 FT_UInt max_function_defs; 295 TT_DefArray function_defs; /* table of function definitions */ 296 297 FT_UInt num_instruction_defs; /* number of ins. definitions */ 298 FT_UInt max_instruction_defs; 299 TT_DefArray instruction_defs; /* table of ins. definitions */ 300 301 FT_UInt max_func; 302 FT_UInt max_ins; 303 304 TT_CodeRangeTable codeRangeTable; 305 306 TT_GraphicsState GS; 307 308 FT_ULong cvt_size; /* the scaled control value table */ 309 FT_Long* cvt; 310 311 FT_UShort storage_size; /* The storage area is now part of */ 312 FT_Long* storage; /* the instance */ 313 314 TT_GlyphZoneRec twilight; /* The instance's twilight zone */ 315 316 TT_ExecContext context; 317 318 /* if negative, `fpgm' (resp. `prep'), wasn't executed yet; */ 319 /* otherwise it is the returned error code */ 320 FT_Error bytecode_ready; 321 FT_Error cvt_ready; 322 323 #endif /* TT_USE_BYTECODE_INTERPRETER */ 324 325 } TT_SizeRec; 326 327 328 /*************************************************************************/ 329 /* */ 330 /* TrueType driver class. */ 331 /* */ 332 typedef struct TT_DriverRec_ 333 { 334 FT_DriverRec root; 335 336 TT_GlyphZoneRec zone; /* glyph loader points zone */ 337 338 FT_UInt interpreter_version; 339 340 } TT_DriverRec; 341 342 343 /* Note: All of the functions below (except tt_size_reset()) are used */ 344 /* as function pointers in a FT_Driver_ClassRec. Therefore their */ 345 /* parameters are of types FT_Face, FT_Size, etc., rather than TT_Face, */ 346 /* TT_Size, etc., so that the compiler can confirm that the types and */ 347 /* number of parameters are correct. In all cases the FT_xxx types are */ 348 /* cast to their TT_xxx counterparts inside the functions since FreeType */ 349 /* will always use the TT driver to create them. */ 350 351 352 /*************************************************************************/ 353 /* */ 354 /* Face functions */ 355 /* */ 356 FT_LOCAL( FT_Error ) 357 tt_face_init( FT_Stream stream, 358 FT_Face ttface, /* TT_Face */ 359 FT_Int face_index, 360 FT_Int num_params, 361 FT_Parameter* params ); 362 363 FT_LOCAL( void ) 364 tt_face_done( FT_Face ttface ); /* TT_Face */ 365 366 367 /*************************************************************************/ 368 /* */ 369 /* Size functions */ 370 /* */ 371 FT_LOCAL( FT_Error ) 372 tt_size_init( FT_Size ttsize ); /* TT_Size */ 373 374 FT_LOCAL( void ) 375 tt_size_done( FT_Size ttsize ); /* TT_Size */ 376 377 #ifdef TT_USE_BYTECODE_INTERPRETER 378 379 FT_LOCAL( FT_Error ) 380 tt_size_run_fpgm( TT_Size size, 381 FT_Bool pedantic ); 382 383 FT_LOCAL( FT_Error ) 384 tt_size_run_prep( TT_Size size, 385 FT_Bool pedantic ); 386 387 FT_LOCAL( FT_Error ) 388 tt_size_ready_bytecode( TT_Size size, 389 FT_Bool pedantic ); 390 391 #endif /* TT_USE_BYTECODE_INTERPRETER */ 392 393 FT_LOCAL( FT_Error ) 394 tt_size_reset( TT_Size size ); 395 396 397 /*************************************************************************/ 398 /* */ 399 /* Driver functions */ 400 /* */ 401 FT_LOCAL( FT_Error ) 402 tt_driver_init( FT_Module ttdriver ); /* TT_Driver */ 403 404 FT_LOCAL( void ) 405 tt_driver_done( FT_Module ttdriver ); /* TT_Driver */ 406 407 408 /*************************************************************************/ 409 /* */ 410 /* Slot functions */ 411 /* */ 412 FT_LOCAL( FT_Error ) 413 tt_slot_init( FT_GlyphSlot slot ); 414 415 416 /* auxiliary */ 417 #define IS_HINTED( flags ) ( ( flags & FT_LOAD_NO_HINTING ) == 0 ) 418 419 420 FT_END_HEADER 421 422 #endif /* __TTOBJS_H__ */ 423 424 425 /* END */ 426
