ref: 17ae985d3838bb4f83644ecad27a87a1a8730a4c
dir: /src/truetype/ttobjs.h/
/***************************************************************************/ /* */ /* ttobjs.h */ /* */ /* Objects manager (specification). */ /* */ /* Copyright 1996-1999 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 TTOBJS_H #define TTOBJS_H #include <ftobjs.h> #include <tttypes.h> #include <ttconfig.h> #include <tterrors.h> #ifdef __cplusplus extern "C" { #endif /*************************************************************************/ /* */ /* <Type> */ /* TT_Driver */ /* */ /* <Description> */ /* A handle to a TrueType driver object. */ /* */ typedef struct TT_DriverRec_* TT_Driver; /*************************************************************************/ /* */ /* <Type> */ /* TT_Instance */ /* */ /* <Description> */ /* A handle to a TrueType size object. */ /* */ typedef struct TT_SizeRec_* TT_Size; /*************************************************************************/ /* */ /* <Type> */ /* TT_GlyphSlot */ /* */ /* <Description> */ /* A handle to a TrueType glyph slot object. */ /* */ /* <Note> */ /* This is a direct typedef of FT_GlyphSlot, as there is nothing */ /* specific about the TrueType glyph slot. */ /* */ typedef FT_GlyphSlot TT_GlyphSlot; /*************************************************************************/ /* */ /* <Struct> */ /* TT_GraphicsState */ /* */ /* <Description> */ /* The TrueType graphics state used during bytecode interpretation. */ /* */ typedef struct TT_GraphicsState_ { TT_UShort rp0; TT_UShort rp1; TT_UShort rp2; TT_UnitVector dualVector; TT_UnitVector projVector; TT_UnitVector freeVector; TT_Long loop; TT_F26Dot6 minimum_distance; TT_Int round_state; TT_Bool auto_flip; TT_F26Dot6 control_value_cutin; TT_F26Dot6 single_width_cutin; TT_F26Dot6 single_width_value; TT_Short delta_base; TT_Short delta_shift; TT_Byte instruct_control; TT_Bool scan_control; TT_Int scan_type; TT_UShort gep0; TT_UShort gep1; TT_UShort gep2; } TT_GraphicsState; /*************************************************************************/ /* */ /* EXECUTION SUBTABLES */ /* */ /* These sub-tables relate to instruction execution. */ /* */ /*************************************************************************/ #define TT_MAX_CODE_RANGES 3 /*************************************************************************/ /* */ /* There can only be 3 active code ranges at once: */ /* - the Font Program */ /* - the CVT Program */ /* - a glyph's instructions set */ /* */ typedef enum TT_CodeRange_Tag_ { tt_coderange_none = 0, tt_coderange_font, tt_coderange_cvt, tt_coderange_glyph } TT_CodeRange_Tag; typedef struct TT_CodeRange_ { TT_Byte* base; TT_ULong size; } TT_CodeRange; typedef TT_CodeRange TT_CodeRangeTable[TT_MAX_CODE_RANGES]; /*************************************************************************/ /* */ /* Defines a function/instruction definition record. */ /* */ typedef struct TT_DefRecord_ { TT_Int range; /* in which code range is it located? */ TT_Long start; /* where does it start? */ TT_UInt opc; /* function #, or instruction code */ TT_Bool active; /* is it active? */ } TT_DefRecord, *TT_DefArray; /*************************************************************************/ /* */ /* This type defining a set of glyph points will be used to represent */ /* each zone (regular and twilight) during instructions decoding. */ /* */ typedef struct TT_GlyphZone_ { TT_UShort n_points; /* number of points in zone */ TT_Short n_contours; /* number of contours */ TT_Vector* org; /* original point coordinates */ TT_Vector* cur; /* current point coordinates */ TT_Byte* touch; /* current touch flags */ TT_UShort* contours; /* contour end points */ } TT_GlyphZone; /*************************************************************************/ /* */ /* Subglyph transformation record. */ /* */ typedef struct TT_Transform_ { TT_Fixed xx, xy; /* transformation matrix coefficients */ TT_Fixed yx, yy; TT_F26Dot6 ox, oy; /* offsets */ } TT_Transform; /*************************************************************************/ /* */ /* Subglyph loading record. Used to load composite components. */ /* */ typedef struct TT_SubglyphRec_ { TT_Long index; /* subglyph index; initialized with -1 */ TT_Bool is_scaled; /* is the subglyph scaled? */ TT_Bool is_hinted; /* should it be hinted? */ TT_Bool preserve_pps; /* preserve phantom points? */ TT_Long file_offset; TT_BBox bbox; TT_Pos left_bearing; TT_Pos advance; TT_GlyphZone zone; TT_Long arg1; /* first argument */ TT_Long arg2; /* second argument */ TT_UShort element_flag; /* current load element flag */ TT_Transform transform; /* transformation matrix */ TT_Vector pp1, pp2; /* phantom points */ } TT_SubGlyphRec, *TT_SubGlyph_Stack; /*************************************************************************/ /* */ /* A note regarding non-squared pixels: */ /* */ /* (This text will probably go into some docs at some time, for now, it */ /* is kept here to explain some definitions in the TIns_Metrics */ /* record). */ /* */ /* The CVT is a one-dimensional array containing values that control */ /* certain important characteristics in a font, like the height of all */ /* capitals, all lowercase letter, default spacing or stem width/height. */ /* */ /* These values are found in FUnits in the font file, and must be scaled */ /* to pixel coordinates before being used by the CVT and glyph programs. */ /* Unfortunately, when using distinct x and y resolutions (or distinct x */ /* and y pointsizes), there are two possible scalings. */ /* */ /* A first try was to implement a `lazy' scheme where all values were */ /* scaled when first used. However, while some values are always used */ /* in the same direction, some others are used under many different */ /* circumstances and orientations. */ /* */ /* I have found a simpler way to do the same, and it even seems to work */ /* in most of the cases: */ /* */ /* - All CVT values are scaled to the maximum ppem size. */ /* */ /* - When performing a read or write in the CVT, a ratio factor is used */ /* to perform adequate scaling. Example: */ /* */ /* x_ppem = 14 */ /* y_ppem = 10 */ /* */ /* We choose ppem = x_ppem = 14 as the CVT scaling size. All cvt */ /* entries are scaled to it. */ /* */ /* x_ratio = 1.0 */ /* y_ratio = y_ppem/ppem (< 1.0) */ /* */ /* We compute the current ratio like: */ /* */ /* - If projVector is horizontal, */ /* ratio = x_ratio = 1.0 */ /* */ /* - if projVector is vertical, */ /* ratio = y_ratio */ /* */ /* - else, */ /* ratio = sqrt( (proj.x * x_ratio) ^ 2 + (proj.y * y_ratio) ^ 2 ) */ /* */ /* Reading a cvt value returns */ /* ratio * cvt[index] */ /* */ /* Writing a cvt value in pixels: */ /* cvt[index] / ratio */ /* */ /* The current ppem is simply */ /* ratio * ppem */ /* */ /*************************************************************************/ /*************************************************************************/ /* */ /* Metrics used by the TrueType size and context objects. */ /* */ typedef struct TT_Size_Metrics_ { /* for non-square pixels */ TT_Long x_ratio; TT_Long y_ratio; TT_UShort ppem; /* maximum ppem size */ TT_Long ratio; /* current ratio */ TT_Fixed scale; TT_F26Dot6 compensations[4]; /* device-specific compensations */ TT_Bool valid; TT_Bool rotated; /* `is the glyph rotated?'-flag */ TT_Bool stretched; /* `is the glyph stretched?'-flag */ } TT_Size_Metrics; /*************************************************************************/ /* */ /* FreeType execution context type. */ /* */ /* This is a forward declaration; the full specification is in the file */ /* `ttinterp.h'. */ /* */ typedef struct TT_ExecContextRec_* TT_ExecContext; /***********************************************************************/ /* */ /* TrueType size class. */ /* */ typedef struct TT_SizeRec_ { FT_SizeRec root; TT_Size_Metrics ttmetrics; TT_UInt num_function_defs; /* number of function definitions */ TT_UInt max_function_defs; TT_DefArray function_defs; /* table of function definitions */ TT_UInt num_instruction_defs; /* number of ins. definitions */ TT_UInt max_instruction_defs; TT_DefArray instruction_defs; /* table of ins. definitions */ TT_UInt max_func; TT_UInt max_ins; TT_CodeRangeTable codeRangeTable; TT_GraphicsState GS; TT_ULong cvt_size; /* the scaled control value table */ TT_Long* cvt; TT_UShort storage_size; /* The storage area is now part of */ TT_Long* storage; /* the instance */ TT_GlyphZone twilight; /* The instance's twilight zone */ /* debugging variables */ /* When using the debugger, we must keep the */ /* execution context tied to the instance */ /* object rather than asking it on demand. */ TT_Bool debug; TT_ExecContext context; } TT_SizeRec; /***********************************************************************/ /* */ /* TrueType driver class. */ /* */ typedef struct TT_DriverRec_ { FT_DriverRec root; TT_ExecContext context; /* execution context */ void* extension_component; } TT_DriverRec; /*************************************************************************/ /* */ /* <Function> */ /* TT_New_GlyphZone */ /* */ /* <Description> */ /* Allocates a new glyph zone. */ /* */ /* <Input> */ /* memory :: A handle to the current memory object. */ /* */ /* maxPoints :: The capacity of glyph zone in points. */ /* */ /* maxContours :: The capacity of glyph zone in contours. */ /* */ /* <InOut> */ /* pts :: A pointer to the target glyph zone record. */ /* */ /* <Return> */ /* TrueType error code. 0 means success. */ /* */ LOCAL_DEF TT_Error TT_New_GlyphZone( FT_Memory memory, TT_GlyphZone* pts, TT_UShort maxPoints, TT_Short maxContours ); /*************************************************************************/ /* */ /* <Function> */ /* TT_Done_GlyphZone */ /* */ /* <Description> */ /* Deallocates a glyph zone. */ /* */ /* <Input> */ /* memory :: A handle to the current memory object. */ /* */ /* pts :: A pointer to the target glyph zone record. */ /* */ /* <Return> */ /* TrueType error code. 0 means success. */ /* */ LOCAL_FUNC TT_Error TT_Done_GlyphZone( FT_Memory memory, TT_GlyphZone* pts ); /*************************************************************************/ /* */ /* <Function> */ /* TT_Init_Face */ /* */ /* <Description> */ /* Initializes a given TrueType face object. */ /* */ /* <Input> */ /* resource :: The source font resource. */ /* face_index :: The index of the font face in the resource. */ /* face :: The newly built face object. */ /* */ /* <Return> */ /* TrueType error code. 0 means success. */ /* */ LOCAL_DEF TT_Error TT_Init_Face( FT_Stream stream, TT_Long face_index, TT_Face face ); /*************************************************************************/ /* */ /* <Function> */ /* TT_Done_Face */ /* */ /* <Description> */ /* Finalizes a given face object. */ /* */ /* <Input> */ /* face :: The target face object to finalize. */ /* */ LOCAL_DEF void TT_Done_Face( TT_Face face ); /*************************************************************************/ /* */ /* <Function> */ /* TT_Init_Size */ /* */ /* <Description> */ /* Initializes a new TrueType size object. */ /* */ /* <Input> */ /* size :: A handle to the size object. */ /* */ /* <Return> */ /* TrueType error code. 0 means success. */ /* */ LOCAL_DEF TT_Error TT_Init_Size( TT_Size size ); /*************************************************************************/ /* */ /* <Function> */ /* TT_Done_Size */ /* */ /* <Description> */ /* The TrueType size object finalizer. */ /* */ /* <Input> */ /* size :: A handle to the target size object. */ /* */ LOCAL_DEF void TT_Done_Size( TT_Size size ); /*************************************************************************/ /* */ /* <Function> */ /* TT_Reset_Size */ /* */ /* <Description> */ /* Resets a TrueType size when resolutions and character dimensions */ /* have been changed. */ /* */ /* <Input> */ /* size :: A handle to the target size object. */ /* */ /* <Return> */ /* TrueType error code. 0 means success. */ /* */ LOCAL_DEF TT_Error TT_Reset_Size( TT_Size size ); /*************************************************************************/ /* */ /* <Function> */ /* TT_Init_GlyphSlot */ /* */ /* <Description> */ /* The TrueType glyph slot initializer. */ /* */ /* <Input> */ /* glyph :: The glyph record to build. */ /* */ /* <Return> */ /* TrueType error code. 0 means success. */ /* */ LOCAL_DEF TT_Error TT_Init_GlyphSlot( TT_GlyphSlot slot ); /*************************************************************************/ /* */ /* <Function> */ /* TT_Done_GlyphSlot */ /* */ /* <Description> */ /* The TrueType glyph slot finalizer. */ /* */ /* <Input> */ /* glyph :: A handle to the glyph slot object. */ /* */ LOCAL_DEF void TT_Done_GlyphSlot( TT_GlyphSlot slot ); /*************************************************************************/ /* */ /* <Function> */ /* TT_Init_Driver */ /* */ /* <Description> */ /* Initializes a given TrueType driver object. */ /* */ /* <Input> */ /* driver :: A handle to the target driver object. */ /* */ /* <Return> */ /* TrueType error code. 0 means success. */ /* */ LOCAL_DEF TT_Error TT_Init_Driver( TT_Driver driver ); /*************************************************************************/ /* */ /* <Function> */ /* TT_Done_Driver */ /* */ /* <Description> */ /* Finalizes a given TrueType driver. */ /* */ /* <Input> */ /* driver :: A handle to the target TrueType driver. */ /* */ LOCAL_DEF void TT_Done_Driver( TT_Driver driver ); #ifdef __cplusplus } #endif #endif /* TTOBJS_H */ /* END */