| /***************************************************************************/ |
| /* */ |
| /* ttinterp.h */ |
| /* */ |
| /* TrueType bytecode interpreter (specification). */ |
| /* */ |
| /* Copyright 1996-2001, 2002 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_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_UShort 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 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_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; |
| |
| |
| 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_Face face ); |
| |
| |
| FT_LOCAL( FT_Error ) |
| TT_Done_Context( TT_ExecContext exec ); |
| |
| FT_LOCAL( FT_Error ) |
| TT_Destroy_Context( TT_ExecContext exec, |
| FT_Memory memory ); |
| |
| 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 */ |
