src/freetype/truetype/ttinterp.h

/***************************************************************************/
/*                                                                         */
/*  ttinterp.h                                                             */
/*                                                                         */
/*    TrueType bytecode interpreter (specification).                       */
/*                                                                         */
/*  Copyright 1996-2000 by                                                 */
/*  David Turner, Robert Wilhelm, and Werner Lemberg.                      */
/*                                                                         */
/*  This file is part of the FreeType project, and may only be used,       */
/*  modified, and distributed under the terms of the FreeType project      */
/*  license, LICENSE.TXT.  By continuing to use, modify, or distribute     */
/*  this file you indicate that you have read the license and              */
/*  understand and accept it fully.                                        */
/*                                                                         */
/***************************************************************************/


#ifndef TTINTERP_H
#define TTINTERP_H


#ifdef FT_FLAT_COMPILE

#include "ttobjs.h"

#else

#include <truetype/ttobjs.h>

#endif


#ifdef __cplusplus
  extern "C" {
#endif


#ifndef TT_CONFIG_OPTION_STATIC_INTEPRETER  /* indirect implementation */

#define EXEC_OP_   TT_ExecContext  exc,
#define EXEC_OP    TT_ExecContext  exc
#define EXEC_ARG_  exc,
#define EXEC_ARG   exc

#else                                       /* static implementation */

#define EXEC_OP_   /* void */
#define EXEC_OP    /* void */
#define EXEC_ARG_  /* void */
#define EXEC_ARG   /* void */

#endif /* TT_CONFIG_OPTION_STATIC_INTERPRETER */


  /*************************************************************************/
  /*                                                                       */
  /* Rounding mode constants.                                              */
  /*                                                                       */
#define TT_Round_Off             5
#define TT_Round_To_Half_Grid    0
#define TT_Round_To_Grid         1
#define TT_Round_To_Double_Grid  2
#define TT_Round_Up_To_Grid      4
#define TT_Round_Down_To_Grid    3
#define TT_Round_Super           6
#define TT_Round_Super_45        7


  /*************************************************************************/
  /*                                                                       */
  /* Function types used by the interpreter, depending on various modes    */
  /* (e.g. the rounding mode, whether to render a vertical or horizontal   */
  /* line etc).                                                            */
  /*                                                                       */
  /*************************************************************************/

  /* Rounding function */
  typedef FT_F26Dot6  (*TT_Round_Func)( EXEC_OP_ FT_F26Dot6  distance,
                                                 FT_F26Dot6  compensation );

  /* Point displacement along the freedom vector routine */
  typedef void  (*TT_Move_Func)( EXEC_OP_ TT_GlyphZone*  zone,
                                          FT_UInt        point,
                                          FT_F26Dot6     distance );

  /* Distance projection along one of the projection vectors */
  typedef FT_F26Dot6  (*TT_Project_Func)( EXEC_OP_ FT_Vector*  v1,
                                                   FT_Vector*  v2 );

  /* reading a cvt value.  Take care of non-square pixels if necessary */
  typedef FT_F26Dot6  (*TT_Get_CVT_Func)( EXEC_OP_ FT_ULong  index );

  /* setting or moving a cvt value.  Take care of non-square pixels  */
  /* if necessary                                                    */
  typedef void  (*TT_Set_CVT_Func)( EXEC_OP_ FT_ULong    index,
                                             FT_F26Dot6  value );


  /*************************************************************************/
  /*                                                                       */
  /* This structure defines a call record, used to manage function calls.  */
  /*                                                                       */
  typedef struct  TT_CallRec_
  {
    FT_Int   Caller_Range;
    FT_Long  Caller_IP;
    FT_Long  Cur_Count;
    FT_Long  Cur_Restart;

  } TT_CallRec, *TT_CallStack;


  /*************************************************************************/
  /*                                                                       */
  /* The main structure for the interpreter which collects all necessary   */
  /* variables and states.                                                 */
  /*                                                                       */
  typedef struct  TT_ExecContextRec_
  {
    TT_Face         face;
    TT_Size         size;
    FT_Memory       memory;

    /* instructions state */

    FT_Error        error;      /* last execution error */

    FT_Long         top;        /* top of exec. stack   */

    FT_UInt         stackSize;  /* size of exec. stack  */
    FT_Long*        stack;      /* current exec. stack  */

    FT_Long         args;
    FT_UInt         new_top;    /* new top after exec.  */

    TT_GlyphZone    zp0,        /* zone records */
                    zp1,
                    zp2,
                    pts,
                    twilight;

    FT_Size_Metrics  metrics;
    TT_Size_Metrics  tt_metrics; /* size metrics */

    TT_GraphicsState  GS;         /* current graphics state */

    FT_Int          curRange;  /* current code range number   */
    FT_Byte*        code;      /* current code range          */
    FT_Long         IP;        /* current instruction pointer */
    FT_Long         codeSize;  /* size of current range       */

    FT_Byte         opcode;    /* current opcode              */
    FT_Int          length;    /* length of current opcode    */

    FT_Bool         step_ins;  /* true if the interpreter must */
                               /* increment IP after ins. exec */
    FT_Long         cvtSize;
    FT_Long*        cvt;

    FT_UInt         glyphSize; /* glyph instructions buffer size */
    FT_Byte*        glyphIns;  /* glyph instructions buffer */

    FT_UInt         numFDefs;  /* number of function defs         */
    FT_UInt         maxFDefs;  /* maximum number of function defs */
    TT_DefArray     FDefs;     /* table of FDefs entries          */

    FT_UInt         numIDefs;  /* number of instruction defs */
    FT_UInt         maxIDefs;  /* maximum number of ins defs */
    TT_DefArray     IDefs;     /* table of IDefs entries     */

    FT_UInt         maxFunc;   /* maximum function index     */
    FT_UInt         maxIns;    /* maximum instruction index  */

    FT_Int          callTop,    /* top of call stack during execution */
                    callSize;   /* size of call stack */
    TT_CallStack    callStack;  /* call stack */

    FT_UShort       maxPoints;    /* capacity of this context's `pts' */
    FT_Short        maxContours;  /* record, expressed in points and  */
                                  /* contours.                        */

    TT_CodeRangeTable  codeRangeTable;  /* table of valid code ranges */
                                        /* useful for the debugger   */

    FT_UShort       storeSize;  /* size of current storage */
    FT_Long*        storage;    /* storage area            */

    FT_F26Dot6      period;     /* values used for the */
    FT_F26Dot6      phase;      /* `SuperRounding'     */
    FT_F26Dot6      threshold;

#if 0
    /* this seems to be unused */
    FT_Int          cur_ppem;       /* ppem along the current proj vector */
#endif

    FT_Bool         instruction_trap;  /* If `True', the interpreter will */
                                       /* exit after each instruction     */

    TT_GraphicsState  default_GS;      /* graphics state resulting from    */
                                       /* the prep program                 */
    FT_Bool          is_composite;     /* true if the glyph is composite   */
    FT_Bool          pedantic_hinting; /* true for pedantic interpretation */

    /* latest interpreter additions */

    FT_Long            F_dot_P;    /* dot product of freedom and projection */
                                   /* vectors                               */
    TT_Round_Func      func_round; /* current rounding function             */

    TT_Project_Func    func_project,   /* current projection function */
                       func_dualproj,  /* current dual proj. function */
                       func_freeProj;  /* current freedom proj. func  */

    TT_Move_Func       func_move;      /* current point move function */

    TT_Get_CVT_Func    func_read_cvt;  /* read a cvt entry              */
    TT_Set_CVT_Func    func_write_cvt; /* write a cvt entry (in pixels) */
    TT_Set_CVT_Func    func_move_cvt;  /* incr a cvt entry (in pixels)  */

    FT_ULong           loadSize;
    TT_SubGlyph_Stack  loadStack;      /* loading subglyph stack */

  } TT_ExecContextRec;


  extern const TT_GraphicsState  tt_default_graphics_state;


  LOCAL_DEF
  FT_Error  TT_Goto_CodeRange( TT_ExecContext  exec,
                               FT_Int          range,
                               FT_Long         IP );

  LOCAL_DEF
  FT_Error  TT_Set_CodeRange( TT_ExecContext  exec,
                              FT_Int          range,
                              void*           base,
                              FT_Long         length );

  LOCAL_DEF
  FT_Error  TT_Clear_CodeRange( TT_ExecContext  exec,
                                FT_Int          range );

  FT_EXPORT_DEF( TT_ExecContext )  TT_New_Context( TT_Face  face );

  LOCAL_DEF
  FT_Error  TT_Done_Context( TT_ExecContext  exec );

  LOCAL_DEF
  FT_Error  TT_Destroy_Context( TT_ExecContext  exec,
                                FT_Memory       memory );

  LOCAL_DEF
  FT_Error  TT_Load_Context( TT_ExecContext  exec,
                             TT_Face         face,
                             TT_Size         size );

  LOCAL_DEF
  FT_Error  TT_Save_Context( TT_ExecContext  exec,
                             TT_Size         ins );

  LOCAL_DEF
  FT_Error  TT_Run_Context( TT_ExecContext  exec,
                            FT_Bool         debug );

  FT_EXPORT_DEF( FT_Error )  TT_RunIns( TT_ExecContext  exec );


#ifdef __cplusplus
  }
#endif

#endif /* TTINTERP_H */


/* END */
Commit	Line	Data
	1	/***************************************************************************/
	2	/* */
	3	/* ttinterp.h */
	4	/* */
	5	/* TrueType bytecode interpreter (specification). */
	6	/* */
	7	/* Copyright 1996-2000 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
	23	#ifdef FT_FLAT_COMPILE
	24
	25	#include "ttobjs.h"
	26
	27	#else
	28
	29	#include <truetype/ttobjs.h>
	30
	31	#endif
	32
	33
	34	#ifdef __cplusplus
	35	extern "C" {
	36	#endif
	37
	38
	39	#ifndef TT_CONFIG_OPTION_STATIC_INTEPRETER /* indirect implementation */
	40
	41	#define EXEC_OP_ TT_ExecContext exc,
	42	#define EXEC_OP TT_ExecContext exc
	43	#define EXEC_ARG_ exc,
	44	#define EXEC_ARG exc
	45
	46	#else /* static implementation */
	47
	48	#define EXEC_OP_ /* void */
	49	#define EXEC_OP /* void */
	50	#define EXEC_ARG_ /* void */
	51	#define EXEC_ARG /* void */
	52
	53	#endif /* TT_CONFIG_OPTION_STATIC_INTERPRETER */
	54
	55
	56	/*************************************************************************/
	57	/* */
	58	/* Rounding mode constants. */
	59	/* */
	60	#define TT_Round_Off 5
	61	#define TT_Round_To_Half_Grid 0
	62	#define TT_Round_To_Grid 1
	63	#define TT_Round_To_Double_Grid 2
	64	#define TT_Round_Up_To_Grid 4
	65	#define TT_Round_Down_To_Grid 3
	66	#define TT_Round_Super 6
	67	#define TT_Round_Super_45 7
	68
	69
	70	/*************************************************************************/
	71	/* */
	72	/* Function types used by the interpreter, depending on various modes */
	73	/* (e.g. the rounding mode, whether to render a vertical or horizontal */
	74	/* line etc). */
	75	/* */
	76	/*************************************************************************/
	77
	78	/* Rounding function */
	79	typedef FT_F26Dot6 (*TT_Round_Func)( EXEC_OP_ FT_F26Dot6 distance,
	80	FT_F26Dot6 compensation );
	81
	82	/* Point displacement along the freedom vector routine */
	83	typedef void (TT_Move_Func)( EXEC_OP_ TT_GlyphZone zone,
	84	FT_UInt point,
	85	FT_F26Dot6 distance );
	86
	87	/* Distance projection along one of the projection vectors */
	88	typedef FT_F26Dot6 (TT_Project_Func)( EXEC_OP_ FT_Vector v1,
	89	FT_Vector* v2 );
	90
	91	/* reading a cvt value. Take care of non-square pixels if necessary */
	92	typedef FT_F26Dot6 (*TT_Get_CVT_Func)( EXEC_OP_ FT_ULong index );
	93
	94	/* setting or moving a cvt value. Take care of non-square pixels */
	95	/* if necessary */
	96	typedef void (*TT_Set_CVT_Func)( EXEC_OP_ FT_ULong index,
	97	FT_F26Dot6 value );
	98
	99
	100	/*************************************************************************/
	101	/* */
	102	/* This structure defines a call record, used to manage function calls. */
	103	/* */
	104	typedef struct TT_CallRec_
	105	{
	106	FT_Int Caller_Range;
	107	FT_Long Caller_IP;
	108	FT_Long Cur_Count;
	109	FT_Long Cur_Restart;
	110
	111	} TT_CallRec, *TT_CallStack;
	112
	113
	114	/*************************************************************************/
	115	/* */
	116	/* The main structure for the interpreter which collects all necessary */
	117	/* variables and states. */
	118	/* */
	119	typedef struct TT_ExecContextRec_
	120	{
	121	TT_Face face;
	122	TT_Size size;
	123	FT_Memory memory;
	124
	125	/* instructions state */
	126
	127	FT_Error error; /* last execution error */
	128
	129	FT_Long top; /* top of exec. stack */
	130
	131	FT_UInt stackSize; /* size of exec. stack */
	132	FT_Long* stack; /* current exec. stack */
	133
	134	FT_Long args;
	135	FT_UInt new_top; /* new top after exec. */
	136
	137	TT_GlyphZone zp0, /* zone records */
	138	zp1,
	139	zp2,
	140	pts,
	141	twilight;
	142
	143	FT_Size_Metrics metrics;
	144	TT_Size_Metrics tt_metrics; /* size metrics */
	145
	146	TT_GraphicsState GS; /* current graphics state */
	147
	148	FT_Int curRange; /* current code range number */
	149	FT_Byte* code; /* current code range */
	150	FT_Long IP; /* current instruction pointer */
	151	FT_Long codeSize; /* size of current range */
	152
	153	FT_Byte opcode; /* current opcode */
	154	FT_Int length; /* length of current opcode */
	155
	156	FT_Bool step_ins; /* true if the interpreter must */
	157	/* increment IP after ins. exec */
	158	FT_Long cvtSize;
	159	FT_Long* cvt;
	160
	161	FT_UInt glyphSize; /* glyph instructions buffer size */
	162	FT_Byte* glyphIns; /* glyph instructions buffer */
	163
	164	FT_UInt numFDefs; /* number of function defs */
	165	FT_UInt maxFDefs; /* maximum number of function defs */
	166	TT_DefArray FDefs; /* table of FDefs entries */
	167
	168	FT_UInt numIDefs; /* number of instruction defs */
	169	FT_UInt maxIDefs; /* maximum number of ins defs */
	170	TT_DefArray IDefs; /* table of IDefs entries */
	171
	172	FT_UInt maxFunc; /* maximum function index */
	173	FT_UInt maxIns; /* maximum instruction index */
	174
	175	FT_Int callTop, /* top of call stack during execution */
	176	callSize; /* size of call stack */
	177	TT_CallStack callStack; /* call stack */
	178
	179	FT_UShort maxPoints; /* capacity of this context's `pts' */
	180	FT_Short maxContours; /* record, expressed in points and */
	181	/* contours. */
	182
	183	TT_CodeRangeTable codeRangeTable; /* table of valid code ranges */
	184	/* useful for the debugger */
	185
	186	FT_UShort storeSize; /* size of current storage */
	187	FT_Long* storage; /* storage area */
	188
	189	FT_F26Dot6 period; /* values used for the */
	190	FT_F26Dot6 phase; /* `SuperRounding' */
	191	FT_F26Dot6 threshold;
	192
	193	#if 0
	194	/* this seems to be unused */
	195	FT_Int cur_ppem; /* ppem along the current proj vector */
	196	#endif
	197
	198	FT_Bool instruction_trap; /* If `True', the interpreter will */
	199	/* exit after each instruction */
	200
	201	TT_GraphicsState default_GS; /* graphics state resulting from */
	202	/* the prep program */
	203	FT_Bool is_composite; /* true if the glyph is composite */
	204	FT_Bool pedantic_hinting; /* true for pedantic interpretation */
	205
	206	/* latest interpreter additions */
	207
	208	FT_Long F_dot_P; /* dot product of freedom and projection */
	209	/* vectors */
	210	TT_Round_Func func_round; /* current rounding function */
	211
	212	TT_Project_Func func_project, /* current projection function */
	213	func_dualproj, /* current dual proj. function */
	214	func_freeProj; /* current freedom proj. func */
	215
	216	TT_Move_Func func_move; /* current point move function */
	217
	218	TT_Get_CVT_Func func_read_cvt; /* read a cvt entry */
	219	TT_Set_CVT_Func func_write_cvt; /* write a cvt entry (in pixels) */
	220	TT_Set_CVT_Func func_move_cvt; /* incr a cvt entry (in pixels) */
	221
	222	FT_ULong loadSize;
	223	TT_SubGlyph_Stack loadStack; /* loading subglyph stack */
	224
	225	} TT_ExecContextRec;
	226
	227
	228	extern const TT_GraphicsState tt_default_graphics_state;
	229
	230
	231	LOCAL_DEF
	232	FT_Error TT_Goto_CodeRange( TT_ExecContext exec,
	233	FT_Int range,
	234	FT_Long IP );
	235
	236	LOCAL_DEF
	237	FT_Error TT_Set_CodeRange( TT_ExecContext exec,
	238	FT_Int range,
	239	void* base,
	240	FT_Long length );
	241
	242	LOCAL_DEF
	243	FT_Error TT_Clear_CodeRange( TT_ExecContext exec,
	244	FT_Int range );
	245
	246	FT_EXPORT_DEF( TT_ExecContext ) TT_New_Context( TT_Face face );
	247
	248	LOCAL_DEF
	249	FT_Error TT_Done_Context( TT_ExecContext exec );
	250
	251	LOCAL_DEF
	252	FT_Error TT_Destroy_Context( TT_ExecContext exec,
	253	FT_Memory memory );
	254
	255	LOCAL_DEF
	256	FT_Error TT_Load_Context( TT_ExecContext exec,
	257	TT_Face face,
	258	TT_Size size );
	259
	260	LOCAL_DEF
	261	FT_Error TT_Save_Context( TT_ExecContext exec,
	262	TT_Size ins );
	263
	264	LOCAL_DEF
	265	FT_Error TT_Run_Context( TT_ExecContext exec,
	266	FT_Bool debug );
	267
	268	FT_EXPORT_DEF( FT_Error ) TT_RunIns( TT_ExecContext exec );
	269
	270
	271	#ifdef __cplusplus
	272	}
	273	#endif
	274
	275	#endif /* TTINTERP_H */
	276
	277
	278	/* END */