/***************************************************************************/ | |
/* */ | |
/* ttinterp.h */ | |
/* */ | |
/* TrueType bytecode interpreter (specification). */ | |
/* */ | |
/* Copyright 1996-2001, 2002, 2003, 2004, 2005, 2006, 2007 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__ | |
#include <ft2build.h> | |
#include "ttobjs.h" | |
FT_BEGIN_HEADER | |
#ifndef TT_CONFIG_OPTION_STATIC_INTERPRETER /* 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_UShort point, | |
FT_F26Dot6 distance ); | |
/* Distance projection along one of the projection vectors */ | |
typedef FT_F26Dot6 | |
(*TT_Project_Func)( EXEC_OP_ FT_Pos dx, | |
FT_Pos dy ); | |
/* reading a cvt value. Take care of non-square pixels if necessary */ | |
typedef FT_F26Dot6 | |
(*TT_Get_CVT_Func)( EXEC_OP_ FT_ULong idx ); | |
/* setting or moving a cvt value. Take care of non-square pixels */ | |
/* if necessary */ | |
typedef void | |
(*TT_Set_CVT_Func)( EXEC_OP_ FT_ULong idx, | |
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_GlyphZoneRec 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 if 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_Move_Func func_move_orig; /* move original position 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_Bool grayscale; /* are we hinting for grayscale? */ | |
} TT_ExecContextRec; | |
extern const TT_GraphicsState tt_default_graphics_state; | |
FT_LOCAL( FT_Error ) | |
TT_Goto_CodeRange( TT_ExecContext exec, | |
FT_Int range, | |
FT_Long IP ); | |
FT_LOCAL( FT_Error ) | |
TT_Set_CodeRange( TT_ExecContext exec, | |
FT_Int range, | |
void* base, | |
FT_Long length ); | |
FT_LOCAL( FT_Error ) | |
TT_Clear_CodeRange( TT_ExecContext exec, | |
FT_Int range ); | |
/*************************************************************************/ | |
/* */ | |
/* <Function> */ | |
/* TT_New_Context */ | |
/* */ | |
/* <Description> */ | |
/* Queries the face context for a given font. Note that there is */ | |
/* now a _single_ execution context in the TrueType driver which is */ | |
/* shared among faces. */ | |
/* */ | |
/* <Input> */ | |
/* face :: A handle to the source face object. */ | |
/* */ | |
/* <Return> */ | |
/* A handle to the execution context. Initialized for `face'. */ | |
/* */ | |
/* <Note> */ | |
/* Only the glyph loader and debugger should call this function. */ | |
/* */ | |
FT_EXPORT( TT_ExecContext ) | |
TT_New_Context( TT_Driver driver ); | |
FT_LOCAL( FT_Error ) | |
TT_Done_Context( TT_ExecContext exec ); | |
FT_LOCAL( FT_Error ) | |
TT_Load_Context( TT_ExecContext exec, | |
TT_Face face, | |
TT_Size size ); | |
FT_LOCAL( FT_Error ) | |
TT_Save_Context( TT_ExecContext exec, | |
TT_Size ins ); | |
FT_LOCAL( FT_Error ) | |
TT_Run_Context( TT_ExecContext exec, | |
FT_Bool debug ); | |
/*************************************************************************/ | |
/* */ | |
/* <Function> */ | |
/* TT_RunIns */ | |
/* */ | |
/* <Description> */ | |
/* Executes one or more instruction in the execution context. This */ | |
/* is the main function of the TrueType opcode interpreter. */ | |
/* */ | |
/* <Input> */ | |
/* exec :: A handle to the target execution context. */ | |
/* */ | |
/* <Return> */ | |
/* FreeType error code. 0 means success. */ | |
/* */ | |
/* <Note> */ | |
/* Only the object manager and debugger should call this function. */ | |
/* */ | |
/* This function is publicly exported because it is directly */ | |
/* invoked by the TrueType debugger. */ | |
/* */ | |
FT_EXPORT( FT_Error ) | |
TT_RunIns( TT_ExecContext exec ); | |
FT_END_HEADER | |
#endif /* __TTINTERP_H__ */ | |
/* END */ |