reactos/lib/3rdparty/freetype/src/truetype/ttinterp.h

   1 /***************************************************************************/
   2 /*                                                                         */
   3 /*  ttinterp.h                                                             */
   4 /*                                                                         */
   5 /*    TrueType bytecode interpreter (specification).                       */
   6 /*                                                                         */
   7 /*  Copyright 1996-2007, 2010, 2012-2013 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 __TTINTERP_H__
  20 #define __TTINTERP_H__
  21
  22 #include <ft2build.h>
  23 #include "ttobjs.h"
  24
  25
  26 FT_BEGIN_HEADER
  27
  28
  29 #ifndef TT_CONFIG_OPTION_STATIC_INTERPRETER /* indirect implementation */
  30
  31 #define EXEC_OP_   TT_ExecContext  exc,
  32 #define EXEC_OP    TT_ExecContext  exc
  33 #define EXEC_ARG_  exc,
  34 #define EXEC_ARG   exc
  35
  36 #else                                       /* static implementation */
  37
  38 #define EXEC_OP_   /* void */
  39 #define EXEC_OP    /* void */
  40 #define EXEC_ARG_  /* void */
  41 #define EXEC_ARG   /* void */
  42
  43 #endif /* TT_CONFIG_OPTION_STATIC_INTERPRETER */
  44
  45
  46   /*************************************************************************/
  47   /*                                                                       */
  48   /* Rounding mode constants.                                              */
  49   /*                                                                       */
  50 #define TT_Round_Off             5
  51 #define TT_Round_To_Half_Grid    0
  52 #define TT_Round_To_Grid         1
  53 #define TT_Round_To_Double_Grid  2
  54 #define TT_Round_Up_To_Grid      4
  55 #define TT_Round_Down_To_Grid    3
  56 #define TT_Round_Super           6
  57 #define TT_Round_Super_45        7
  58
  59
  60   /*************************************************************************/
  61   /*                                                                       */
  62   /* Function types used by the interpreter, depending on various modes    */
  63   /* (e.g. the rounding mode, whether to render a vertical or horizontal   */
  64   /* line etc).                                                            */
  65   /*                                                                       */
  66   /*************************************************************************/
  67
  68   /* Rounding function */
  69   typedef FT_F26Dot6
  70   (*TT_Round_Func)( EXEC_OP_ FT_F26Dot6  distance,
  71                              FT_F26Dot6  compensation );
  72
  73   /* Point displacement along the freedom vector routine */
  74   typedef void
  75   (*TT_Move_Func)( EXEC_OP_ TT_GlyphZone  zone,
  76                             FT_UShort     point,
  77                             FT_F26Dot6    distance );
  78
  79   /* Distance projection along one of the projection vectors */
  80   typedef FT_F26Dot6
  81   (*TT_Project_Func)( EXEC_OP_ FT_Pos   dx,
  82                                FT_Pos   dy );
  83
  84   /* reading a cvt value.  Take care of non-square pixels if necessary */
  85   typedef FT_F26Dot6
  86   (*TT_Get_CVT_Func)( EXEC_OP_ FT_ULong  idx );
  87
  88   /* setting or moving a cvt value.  Take care of non-square pixels  */
  89   /* if necessary                                                    */
  90   typedef void
  91   (*TT_Set_CVT_Func)( EXEC_OP_ FT_ULong    idx,
  92                                FT_F26Dot6  value );
  93
  94
  95   /*************************************************************************/
  96   /*                                                                       */
  97   /* This structure defines a call record, used to manage function calls.  */
  98   /*                                                                       */
  99   typedef struct  TT_CallRec_
 100   {
 101     FT_Int   Caller_Range;
 102     FT_Long  Caller_IP;
 103     FT_Long  Cur_Count;
 104
 105     TT_DefRecord  *Def; /* either FDEF or IDEF */
 106
 107   } TT_CallRec, *TT_CallStack;
 108
 109
 110 #ifdef TT_CONFIG_OPTION_SUBPIXEL_HINTING
 111
 112   /*************************************************************************/
 113   /*                                                                       */
 114   /* These structures define rules used to tweak subpixel hinting for      */
 115   /* various fonts.  "", 0, "", NULL value indicates to match any value.   */
 116   /*                                                                       */
 117
 118 #define SPH_MAX_NAME_SIZE      32
 119 #define SPH_MAX_CLASS_MEMBERS  100
 120
 121   typedef struct  SPH_TweakRule_
 122   {
 123     const char      family[SPH_MAX_NAME_SIZE];
 124     const FT_UInt   ppem;
 125     const char      style[SPH_MAX_NAME_SIZE];
 126     const FT_ULong  glyph;
 127
 128   } SPH_TweakRule;
 129
 130
 131   typedef struct  SPH_ScaleRule_
 132   {
 133     const char      family[SPH_MAX_NAME_SIZE];
 134     const FT_UInt   ppem;
 135     const char      style[SPH_MAX_NAME_SIZE];
 136     const FT_ULong  glyph;
 137     const FT_ULong  scale;
 138
 139   } SPH_ScaleRule;
 140
 141
 142   typedef struct  SPH_Font_Class_
 143   {
 144     const char  name[SPH_MAX_NAME_SIZE];
 145     const char  member[SPH_MAX_CLASS_MEMBERS][SPH_MAX_NAME_SIZE];
 146
 147   } SPH_Font_Class;
 148
 149 #endif /* TT_CONFIG_OPTION_SUBPIXEL_HINTING */
 150
 151
 152   /*************************************************************************/
 153   /*                                                                       */
 154   /* The main structure for the interpreter which collects all necessary   */
 155   /* variables and states.                                                 */
 156   /*                                                                       */
 157   typedef struct  TT_ExecContextRec_
 158   {
 159     TT_Face            face;
 160     TT_Size            size;
 161     FT_Memory          memory;
 162
 163     /* instructions state */
 164
 165     FT_Error           error;      /* last execution error */
 166
 167     FT_Long            top;        /* top of exec. stack   */
 168
 169     FT_UInt            stackSize;  /* size of exec. stack  */
 170     FT_Long*           stack;      /* current exec. stack  */
 171
 172     FT_Long            args;
 173     FT_UInt            new_top;    /* new top after exec.  */
 174
 175     TT_GlyphZoneRec    zp0,        /* zone records */
 176                        zp1,
 177                        zp2,
 178                        pts,
 179                        twilight;
 180
 181     FT_Size_Metrics    metrics;
 182     TT_Size_Metrics    tt_metrics; /* size metrics */
 183
 184     TT_GraphicsState   GS;         /* current graphics state */
 185
 186     FT_Int             curRange;  /* current code range number   */
 187     FT_Byte*           code;      /* current code range          */
 188     FT_Long            IP;        /* current instruction pointer */
 189     FT_Long            codeSize;  /* size of current range       */
 190
 191     FT_Byte            opcode;    /* current opcode              */
 192     FT_Int             length;    /* length of current opcode    */
 193
 194     FT_Bool            step_ins;  /* true if the interpreter must */
 195                                   /* increment IP after ins. exec */
 196     FT_ULong           cvtSize;
 197     FT_Long*           cvt;
 198
 199     FT_UInt            glyphSize; /* glyph instructions buffer size */
 200     FT_Byte*           glyphIns;  /* glyph instructions buffer */
 201
 202     FT_UInt            numFDefs;  /* number of function defs         */
 203     FT_UInt            maxFDefs;  /* maximum number of function defs */
 204     TT_DefArray        FDefs;     /* table of FDefs entries          */
 205
 206     FT_UInt            numIDefs;  /* number of instruction defs */
 207     FT_UInt            maxIDefs;  /* maximum number of ins defs */
 208     TT_DefArray        IDefs;     /* table of IDefs entries     */
 209
 210     FT_UInt            maxFunc;   /* maximum function index     */
 211     FT_UInt            maxIns;    /* maximum instruction index  */
 212
 213     FT_Int             callTop,    /* top of call stack during execution */
 214                        callSize;   /* size of call stack */
 215     TT_CallStack       callStack;  /* call stack */
 216
 217     FT_UShort          maxPoints;    /* capacity of this context's `pts' */
 218     FT_Short           maxContours;  /* record, expressed in points and  */
 219                                      /* contours.                        */
 220
 221     TT_CodeRangeTable  codeRangeTable;  /* table of valid code ranges */
 222                                         /* useful for the debugger   */
 223
 224     FT_UShort          storeSize;  /* size of current storage */
 225     FT_Long*           storage;    /* storage area            */
 226
 227     FT_F26Dot6         period;     /* values used for the */
 228     FT_F26Dot6         phase;      /* `SuperRounding'     */
 229     FT_F26Dot6         threshold;
 230
 231 #if 0
 232     /* this seems to be unused */
 233     FT_Int             cur_ppem;   /* ppem along the current proj vector */
 234 #endif
 235
 236     FT_Bool            instruction_trap; /* If `True', the interpreter will */
 237                                          /* exit after each instruction     */
 238
 239     TT_GraphicsState   default_GS;       /* graphics state resulting from   */
 240                                          /* the prep program                */
 241     FT_Bool            is_composite;     /* true if the glyph is composite  */
 242     FT_Bool            pedantic_hinting; /* true if pedantic interpretation */
 243
 244     /* latest interpreter additions */
 245
 246     FT_Long            F_dot_P;    /* dot product of freedom and projection */
 247                                    /* vectors                               */
 248     TT_Round_Func      func_round; /* current rounding function             */
 249
 250     TT_Project_Func    func_project,   /* current projection function */
 251                        func_dualproj,  /* current dual proj. function */
 252                        func_freeProj;  /* current freedom proj. func  */
 253
 254     TT_Move_Func       func_move;      /* current point move function */
 255     TT_Move_Func       func_move_orig; /* move original position function */
 256
 257     TT_Get_CVT_Func    func_read_cvt;  /* read a cvt entry              */
 258     TT_Set_CVT_Func    func_write_cvt; /* write a cvt entry (in pixels) */
 259     TT_Set_CVT_Func    func_move_cvt;  /* incr a cvt entry (in pixels)  */
 260
 261     FT_Bool            grayscale;      /* are we hinting for grayscale? */
 262
 263 #ifdef TT_CONFIG_OPTION_SUBPIXEL_HINTING
 264     TT_Round_Func      func_round_sphn;   /* subpixel rounding function */
 265
 266     FT_Bool            subpixel;          /* Using subpixel hinting?       */
 267     FT_Bool            ignore_x_mode;     /* Standard rendering mode for   */
 268                                           /* subpixel hinting.  On if gray */
 269                                           /* or subpixel hinting is on.    */
 270
 271     /* The following 4 aren't fully implemented but here for MS rasterizer */
 272     /* compatibility.                                                      */
 273     FT_Bool            compatible_widths;     /* compatible widths?        */
 274     FT_Bool            symmetrical_smoothing; /* symmetrical_smoothing?    */
 275     FT_Bool            bgr;                   /* bgr instead of rgb?       */
 276     FT_Bool            subpixel_positioned;   /* subpixel positioned       */
 277                                               /* (DirectWrite ClearType)?  */
 278
 279     FT_Int             rasterizer_version;    /* MS rasterizer version     */
 280
 281     FT_Bool            iup_called;            /* IUP called for glyph?     */
 282
 283     FT_ULong           sph_tweak_flags;       /* flags to control          */
 284                                               /* hint tweaks               */
 285
 286     FT_ULong           sph_in_func_flags;     /* flags to indicate if in   */
 287                                               /* special functions         */
 288
 289 #endif /* TT_CONFIG_OPTION_SUBPIXEL_HINTING */
 290
 291   } TT_ExecContextRec;
 292
 293
 294   extern const TT_GraphicsState  tt_default_graphics_state;
 295
 296
 297 #ifdef TT_USE_BYTECODE_INTERPRETER
 298   FT_LOCAL( FT_Error )
 299   TT_Goto_CodeRange( TT_ExecContext  exec,
 300                      FT_Int          range,
 301                      FT_Long         IP );
 302
 303   FT_LOCAL( FT_Error )
 304   TT_Set_CodeRange( TT_ExecContext  exec,
 305                     FT_Int          range,
 306                     void*           base,
 307                     FT_Long         length );
 308
 309   FT_LOCAL( FT_Error )
 310   TT_Clear_CodeRange( TT_ExecContext  exec,
 311                       FT_Int          range );
 312
 313
 314   FT_LOCAL( FT_Error )
 315   Update_Max( FT_Memory  memory,
 316               FT_ULong*  size,
 317               FT_Long    multiplier,
 318               void*      _pbuff,
 319               FT_ULong   new_max );
 320 #endif /* TT_USE_BYTECODE_INTERPRETER */
 321
 322
 323   /*************************************************************************/
 324   /*                                                                       */
 325   /* <Function>                                                            */
 326   /*    TT_New_Context                                                     */
 327   /*                                                                       */
 328   /* <Description>                                                         */
 329   /*    Queries the face context for a given font.  Note that there is     */
 330   /*    now a _single_ execution context in the TrueType driver which is   */
 331   /*    shared among faces.                                                */
 332   /*                                                                       */
 333   /* <Input>                                                               */
 334   /*    face :: A handle to the source face object.                        */
 335   /*                                                                       */
 336   /* <Return>                                                              */
 337   /*    A handle to the execution context.  Initialized for `face'.        */
 338   /*                                                                       */
 339   /* <Note>                                                                */
 340   /*    Only the glyph loader and debugger should call this function.      */
 341   /*                                                                       */
 342   FT_EXPORT( TT_ExecContext )
 343   TT_New_Context( TT_Driver  driver );
 344
 345
 346 #ifdef TT_USE_BYTECODE_INTERPRETER
 347   FT_LOCAL( FT_Error )
 348   TT_Done_Context( TT_ExecContext  exec );
 349
 350   FT_LOCAL( FT_Error )
 351   TT_Load_Context( TT_ExecContext  exec,
 352                    TT_Face         face,
 353                    TT_Size         size );
 354
 355   FT_LOCAL( FT_Error )
 356   TT_Save_Context( TT_ExecContext  exec,
 357                    TT_Size         ins );
 358
 359   FT_LOCAL( FT_Error )
 360   TT_Run_Context( TT_ExecContext  exec,
 361                   FT_Bool         debug );
 362 #endif /* TT_USE_BYTECODE_INTERPRETER */
 363
 364
 365   /*************************************************************************/
 366   /*                                                                       */
 367   /* <Function>                                                            */
 368   /*    TT_RunIns                                                          */
 369   /*                                                                       */
 370   /* <Description>                                                         */
 371   /*    Executes one or more instruction in the execution context.  This   */
 372   /*    is the main function of the TrueType opcode interpreter.           */
 373   /*                                                                       */
 374   /* <Input>                                                               */
 375   /*    exec :: A handle to the target execution context.                  */
 376   /*                                                                       */
 377   /* <Return>                                                              */
 378   /*    FreeType error code.  0 means success.                             */
 379   /*                                                                       */
 380   /* <Note>                                                                */
 381   /*    Only the object manager and debugger should call this function.    */
 382   /*                                                                       */
 383   /*    This function is publicly exported because it is directly          */
 384   /*    invoked by the TrueType debugger.                                  */
 385   /*                                                                       */
 386   FT_EXPORT( FT_Error )
 387   TT_RunIns( TT_ExecContext  exec );
 388
 389
 390 FT_END_HEADER
 391
 392 #endif /* __TTINTERP_H__ */
 393
 394
 395 /* END */