// Copyright (c) 1998-2010 Nokia Corporation and/or its subsidiary(-ies).

 // All rights reserved.

 // This component and the accompanying materials are made available

 // under the terms of "Eclipse Public License v1.0"

 // which accompanies this distribution, and is available

 // at the URL "http://www.eclipse.org/legal/epl-v10.html".

 //

 // Initial Contributors:

 // Nokia Corporation - initial contribution.

 //

 // Contributors:

 //

 // Description:

 //

 #ifndef __GDI_H__

 #define __GDI_H__

 #include <e32base.h>

 #include <f32file.h>

 #include <s32std.h>

 #include <displaymode.h>

 #ifndef SYMBIAN_ENABLE_SPLIT_HEADERS	

 #include <graphics/gdi/glyphsample.h>

 #include <graphics/gdi/gdiconsts.h>

 #endif //SYMBIAN_ENABLE_SPLIT_HEADERS	

 class TOpenFontCharMetrics;

 class RShapeInfo;

 class CGraphicsContext;

 class TTextParameters;

 /**

 Number of twips per inch. 

 @publishedAll

 @released

 */

 const TInt KTwipsPerInch=1440;

 /**

 Number of twips per point.

 @publishedAll

 @released

 */

 const TInt KTwipsPerPoint=20;

 /**

 Number of points per inch. 

 @publishedAll

 @released

 */

 const TInt KPointsPerInch=72;

 /**

 Number of twips per cm.

 @publishedAll

 @released

 */

 const TInt KTwipsPerCm=567;

 #if defined(__NO_CLASS_CONSTS__)

 /**

 A4 paper size in twips. 

 @publishedAll

 @released

 */

 #define KA4PaperSizeInTwips TSize(11906,16838)

 /** Legal paper size in twips.

 @publishedAll

 @released

 */

 #define KLegalPaperSizeInTwips TSize(12240,20160)

 /**

 Executive paper size in twips. 

 @publishedAll

 @released

 */

 #define KExecutivePaperSizeInTwips TSize(10440,15120)

 /** 

 Letter paper size in twips. 

 @publishedAll

 @released

 */

 #define KLetterPaperSizeInTwips TSize(12240,15840)

 /**

 Com-10 paper size in twips. 

 @publishedAll

 @released

 */

 #define KCom_10PaperSizeInTwips TSize(5940,13680)

 /**

 Monarch paper size in twips. 

 @publishedAll

 @released

 */

 #define KMonarchPaperSizeInTwips TSize(5580,10800)

 /**

 DL paper size in twips. 

 @publishedAll

 @released

 */

 #define KDLPaperSizeInTwips TSize(6236,12472)

 /**

 C5 paper size in twips. 

 @publishedAll

 @released

 */

 #define KC5PaperSizeInTwips TSize(9184,12983)

 #else

 /**

 @publishedAll

 @released

 */

 const TSize KA4PaperSizeInTwips(11906,16838);

 const TSize KLegalPaperSizeInTwips(12240,20160);

 const TSize KExecutivePaperSizeInTwips(10440,15120);

 const TSize KLetterPaperSizeInTwips(12240,15840);

 const TSize KCom_10PaperSizeInTwips(5940,13680);

 const TSize KMonarchPaperSizeInTwips(5580,10800);

 const TSize KDLPaperSizeInTwips(6236,12472);

 const TSize KC5PaperSizeInTwips(9184,12983);

 #endif

 /**

 This enumeration holds the possible panic codes that may be raised 

 by the GDI API on detecting an unrecoverable error. */

 enum TGdiPanic

 	{

 	/** Not used */

 	EGdiPanic_Unknown				= 0,

 	/** One or more of the input parameters to the interface were invalid */

 	EGdiPanic_InvalidInputParam		= 1,

 	/** Insufficient text for successful completion of the method */

 	EGdiPanic_OutOfText				= 2,

 	/** Internal failure. */

 	EGdiPanic_Invariant				= 3,

 	/** Unused panic codes. Can be reused if needed. */

 	EGdiPanic_Unused1				= 4,

 	EGdiPanic_Unused2				= 5,

 	/** Setting a typeface name that is too long */

 	EGdiPanic_TypefaceNameOverflow	= 6,

 	};

 /** 24-bit RGB colour value with 8 bits each for red, green and blue.

 All Graphics drawing functions are specified in terms of a 32-bit TRgb colour 

 containing the three colour values plus 8 bits for alpha channel. For hardware which 

 does not support 24-bit colour, a mapping from TRgb to display colours is 

 performed. 

 Generally, the convention for the alpha blending fact is 0 = transparent, 

 255 = opaque, unless otherwise stated.  The exception to this are the TRgb constructor 

 taking a single value, where the top byte of the passed in parameter is used for 

 alpha information and the function Value(), which returns alpha information in the top byte.

 In both these cases, 0 means opaque, 255 means transparent.

 The supported display modes are enumerated in the TDisplayMode type. In each 

 display mode a unique index can represent each physical colours supported, 

 and which can be mapped onto a full RGB value. The mappings are as follows: 

 16-colour displays use the EGA colour set: black, white, and then both light 

 and dark versions of grey, red, green, blue, cyan, magenta and yellow

 256-colour displays support 216 colours made up of 6x6x6 RGB values, each 

 containing all possible multiples of 51 for R,G,B values. Additionally, all 

 remaining 10 shades of pure red, green, blue and grey are represented, by 

 adding all remaining multiples of 17. This use of 256 colours is sometimes 

 known as the Netscape colour cube.

 4096-colour displays effectively support RGB values with 4 bits per primary 

 colour

 64k-colour displays effectively support RGB values with 5 bits allocated to 

 red, 6 to green and 5 to blue

 16 million-colour displays support true colour with 8 bits allocated to each 

 primary colour

 @publishedAll

 @released

 @see TDisplayMode

 @see DynamicPalette */

 class TRgb

 	{

 public:

 	inline TRgb();

 	inline TRgb(TUint32 aValue);

 	inline TRgb(TUint32 aInternalValue, TInt aAlpha);

 	inline TRgb(TInt aRed,TInt aGreen,TInt aBlue);

 	inline TRgb(TInt aRed, TInt aGreen, TInt aBlue, TInt aAlpha);

 	inline TInt Red() const;

 	inline TInt Green() const;

 	inline TInt Blue() const;

 	inline TInt Alpha() const;

 	IMPORT_C void SetRed(TInt aRed);

 	IMPORT_C void SetGreen(TInt aGreen);

 	IMPORT_C void SetBlue(TInt aBlue);

 	IMPORT_C void SetAlpha(TInt aAlpha);

 	IMPORT_C static TRgb Gray2(TInt aGray2);

 	IMPORT_C static TRgb Gray4(TInt aGray4);

 	IMPORT_C static TRgb Gray16(TInt aGray16);

 	IMPORT_C static TRgb Gray256(TInt aGray256);

 	IMPORT_C static TRgb Color16(TInt aColor16);

 	IMPORT_C static TRgb Color256(TInt aColor256);

 	IMPORT_C static TRgb Color4K(TInt aColor4K);

 	IMPORT_C static TRgb Color64K(TInt aColor64K);

 	IMPORT_C static TRgb Color16M(TInt aColor16M);

 	IMPORT_C TInt Gray2() const;

 	IMPORT_C TInt Gray4() const;

 	IMPORT_C TInt Gray16() const;

 	IMPORT_C TInt Gray256() const;

 	IMPORT_C TInt Color16() const;

 	IMPORT_C TInt Color256() const;

 	IMPORT_C TInt Color4K() const;

 	IMPORT_C TInt Color64K() const;

 	IMPORT_C TInt Color16M() const;

 	inline TBool operator==(const TRgb& aColor) const;

 	inline TBool operator!=(const TRgb& aColor) const;

 	inline TRgb operator~() const;

 	inline TRgb operator&(const TRgb& aColor);

 	inline TRgb operator|(const TRgb& aColor);

 	inline TRgb operator^(const TRgb& aColor);

 	inline TRgb& operator&=(const TRgb& aColor);

 	inline TRgb& operator|=(const TRgb& aColor);

 	inline TRgb& operator^=(const TRgb& aColor);

 	inline TUint32 Value() const;

 	inline TUint32 Internal() const;

 	inline void SetInternal(TUint32 aInternal);

 	IMPORT_C TInt Difference(const TRgb& aColor) const;

 	IMPORT_C void InternalizeL(RReadStream& aStream);

 	IMPORT_C void ExternalizeL(RWriteStream& aStream) const;

 	IMPORT_C static TRgb Color16MU(TInt a0RGB);

 	IMPORT_C TInt Color16MU() const;

 	IMPORT_C static TRgb Color16MA(TUint aARGB);

 	IMPORT_C TUint Color16MA() const;

 	IMPORT_C static TRgb Color16MAP(TUint aARGB);

 	IMPORT_C TUint Color16MAP() const;

 	IMPORT_C TUint _Color16MAP() const;

 	IMPORT_C static TRgb _Color16MAP(TUint aARGB);

 	inline TInt _Gray2() const;

 	inline TInt _Gray4() const;

 	inline TInt _Gray16() const;

 	inline TInt _Gray256() const;

 	inline TInt _Color4K() const;

 	inline TInt _Color64K() const;

 	inline TInt _Color16M() const;

 	inline TInt _Color16MU() const;

 	inline TUint _Color16MA() const;

 	inline static TRgb _Gray2(TInt aGray2);

 	inline static TRgb _Gray4(TInt aGray4);

 	inline static TRgb _Gray16(TInt aGray16);

 	inline static TRgb _Gray256(TInt aGray256);

 	inline static TRgb _Color4K(TInt aColor4K);

 	inline static TRgb _Color64K(TInt aColor64K);

 	inline static TRgb _Color16M(TInt aColor16M);

 	inline static TRgb _Color16MU(TInt a0RGB);

 	inline static TRgb _Color16MA(TUint aARGB);

 private:

 	TUint32 iValue;

 	};

 /**

 @publishedAll

 @released

 */

 #define KRgbBlack		TRgb(0x000000)

 #define KRgbDarkGray	TRgb(0x555555)

 #define KRgbDarkRed		TRgb(0x000080)

 #define KRgbDarkGreen	TRgb(0x008000)

 #define KRgbDarkYellow	TRgb(0x008080)

 #define KRgbDarkBlue	TRgb(0x800000)

 #define KRgbDarkMagenta	TRgb(0x800080)

 #define KRgbDarkCyan	TRgb(0x808000)

 #define KRgbRed			TRgb(0x0000ff)

 #define KRgbGreen		TRgb(0x00ff00)

 #define KRgbYellow		TRgb(0x00ffff)

 #define KRgbBlue		TRgb(0xff0000)

 #define KRgbMagenta		TRgb(0xff00ff)

 #define KRgbCyan		TRgb(0xffff00)

 #define KRgbGray		TRgb(0xaaaaaa)

 #define KRgbWhite		TRgb(0xffffff)

 #define KRgbTransparent	TRgb(0x000000,0x00)

 /** A set of static utility functions to get information about a display mode. 

 @publishedAll 

 @released

 */

 class TDisplayModeUtils

 	{

 public:

 	IMPORT_C static TBool IsDisplayModeColor(TDisplayMode aDispMode);

 	IMPORT_C static TBool IsDisplayModeValid(TDisplayMode aDispMode);

 	IMPORT_C static TInt NumDisplayModeColors(TDisplayMode aDispMode);

 	IMPORT_C static TInt NumDisplayModeBitsPerPixel(TDisplayMode aDispMode);

 	};

 /** Provides user-definable palette support to the GDI.

 A palette is a user-defined set of colours, which is a subset of the full 

 range of 24-bit colours. This allows users the advantages of having a low 

 bpp colour mode whilst being able to specify the colours available in that 

 mode. To give an example, the EColor16 mode provides a palette of 16 colours 

 as it provides a mapping between an integer index and a TRgb colour (see the 

 table EGA Low-colour constants). Only a palette of 16 colour enables you to 

 change the palette. Palettes are also used to allow 24-bit bitmaps to be stored 

 in a more compressed form by finding the actual number of different colours 

 used in the bitmap, creating a palette to allow the mapping of these colours 

 to a smaller index space, and encoding the bitmaps pixels using indexes 

 to this new index space. 

 A palette has a size which is set at its creation and cannot be altered 

 the number of entries in the palette. Each entry in a palette is a mapping 

 between that entrys index and a TRgb value. Palette entries can be got 

 and set at any time between the palettes creation and destruction. The 

 GDIs palette support also provides functions to find the nearest palette 

 colour to a requested TRgb colour. 

 @publishedAll

 @released

 */

 class CPalette : public CBase

 	{

 public:

 	IMPORT_C static CPalette* NewL(TInt aNumberOfEntries);

 	IMPORT_C static CPalette* NewDefaultL(TDisplayMode aDispMode);

 	IMPORT_C ~CPalette();

 	IMPORT_C void Clear();

 	inline TInt Entries() const;

 	IMPORT_C TRgb GetEntry(TInt aPaletteIndex) const;

 	IMPORT_C TRgb NearestEntry(const TRgb& aColor) const;

 	IMPORT_C TInt NearestIndex(const TRgb& aColor) const;

 	IMPORT_C void SetEntry(TInt aPaletteIndex,const TRgb& aPaletteEntry);

 	IMPORT_C void GetDataPtr(TInt aFirstColor,TInt aNumColors,TPtr8& aPtr);

 protected:

 	IMPORT_C CPalette();

 	void ConstructL(TInt aNumberOfEntries);

 protected:

 	TRgb* iArray;

 	TInt iNumEntries;

 	};

 /** Enables conversion, in both directions, between a TRgb object and an index 

 into an arbitrary 256 colour palette. 

 @publishedAll 

 @released

 */

 class TColor256Util

 	{

 public:

 	IMPORT_C void Construct(const CPalette& aPalette);

 	IMPORT_C TInt Color256(TRgb aRgb) const;

 	IMPORT_C void Color256(TUint8* aDestination,const TRgb* aSource,TInt aNumPixels) const;

 	inline TRgb Color256(TInt aColor256) const;

 	IMPORT_C static const TColor256Util* Default();

 public:

 	/** 256 colour lookup table.

 	Each entry is a 32 bit value which corresponds to a TRgb value in the 

 	palette passed to Construct(). If there are more than 256 colours in the 

 	palette, the first 256 colours are used in this table. If there are fewer 

 	than 256 entries, the remaining entries in the table are set to zero. */

 	TUint32	iColorTable[256];

 	/** Inverse colour lookup table.

 	It has 4096 entries. Each entry is the index of a colour in the palette 

 	that the object was created with (see Construct()) that most closely 

 	matches the 4096 degrees of intensity of red, green and blue on a uniform 

 	16x16x16 colour cube.

 	It is called "inverse" because iColorTable maps indices (0..255) to TRgb 

 	values, but this table maps TRgb values to palette indices. */

 	TUint8	iInverseColorTable[0x1000];

 	};

 /** Linear digital differential analyser.

 This is used to calculate the pixels which most closely approximate a specified 

 straight line, or when scaling a bitmap. Note that a line is infinitely thin, 

 and can only be approximated by pixels with real width and height.

 Functions are provided for: pixel line traversing; jumping to a rectangle or 

 co-ordinate 

 @publishedAll 

 @released

 */

 class TLinearDDA

 	{

 public:

 	/** LDDA Line mode. */

 	enum TLineMode

 		{

 		/** Centres scan-lines in the pixel line */

 		ECenter,

 		/** Starts at the beginning of a complete scan line. Used for bitmap 

 		scaling. */

 		ELeft

 		};

 public:

 	IMPORT_C TLinearDDA();

 	IMPORT_C TLinearDDA(const TLinearDDA& aLine);

 	IMPORT_C void Construct(const TPoint& aStart,const TPoint& aFinish,TLineMode aMode=ECenter);

 	IMPORT_C TBool SingleStep(TPoint& aPosition);

 	IMPORT_C TBool SingleScanline(TPoint& aStartPosition,TPoint& aEndPosition);

 	IMPORT_C TBool NextStep(TPoint& aPosition);

 	IMPORT_C void JumpToRect(const TRect& aRect);

 	IMPORT_C void JumpToXCoord(const TInt aXCoord,TInt& aYCoord);

 	IMPORT_C void JumpToYCoord(TInt& aXCoord,const TInt aYCoord);

 	IMPORT_C void JumpToXCoord2(TInt aXCoord,TInt& aYCoord);

 	IMPORT_C void JumpToYCoord2(TInt& aXCoord,TInt aYCoord);

 private:

 	void UpdatePosition();

 private:

 	enum TLineStatus

 		{

 		EInitialised,

 		ECurrent,

 		EComplete

 		};

 private:

 	TInt iCount;

 	TSize iDifference;

 	TPoint iFinish;

 	TInt iGradient;

 	TPoint iInc;

 	TPoint iPos;

 	TPoint iStart;

 	TRect iBoundingRect;

 	TBool iBoundingRectSet;

 	TInt16 iInsideX; // boolean, defined as TInt16 to maintain binary compatibility

 	TInt16 iInsideY; // boolean, defined as TInt16 to maintain binary compatibility

 	TLineStatus iStatus;

 	};

 /**

 Font posture flags.

 Fonts can be either upright or italic. 

 @publishedAll	

 @released

 */

 enum TFontPosture

 	{

 	/** Font posture is normal (upright). */

 	EPostureUpright,

 	/** Font posture is italic. */

 	EPostureItalic

 	};

 /**

 Font stroke weight flags. 

 @publishedAll	

 @released

 */

 enum TFontStrokeWeight

 	{

 	/** Font stroke weight is normal. */

 	EStrokeWeightNormal,

 	/** Font stroke weight is bold. */

 	EStrokeWeightBold

 	};

 /**

 Font print position flags.

 Fonts can be normal, superscript or subscript. 

 @publishedAll	

 @released

 */

 enum TFontPrintPosition

 	{

 	/** Font is normal. */

 	EPrintPosNormal,

 	/** Font is superscript. */

 	EPrintPosSuperscript,

 	/** Font is subscript. */

 	EPrintPosSubscript

 	};

 /**

 Font underline flags. 

 @publishedAll	

 @released

 */

 enum TFontUnderline

 	{

 	/** Font is not underlined. */

 	EUnderlineOff,

 	/** Font is underlined. */

 	EUnderlineOn

 	};

 /**

 Font strike-through flags. 

 @publishedAll	

 @released

 */

 enum TFontStrikethrough

 	{

 	/** Font is not struck-through. */

 	EStrikethroughOff,

 	/** Font is struck-through. */

 	EStrikethroughOn

 	};

 /**

 The maximum length of a typeface name (in characters). 

 @publishedAll	

 @released

 */

 const TInt KMaxTypefaceNameLength=0x18;

 /** Typeface name and attributes.

 This class identifies a typeface by name, and contains the combination of 

 attributes of the typeface. These attributes define whether it is a symbol 

 typeface, whether the typeface is proportional, and whether it is serif or 

 sans-serif. 

 The combination of attributes for a typeface are stored in a bitmask, with 

 the various bits indicating different attributes. The bitmask is calculated 

 for any particular attribute combination by ORing the enumerated value for 

 each individual attribute. 

 @publishedAll 

 @released

 */

 class TTypeface

     {

 public:

 	enum

 		{

 		/** Typeface is a proportional typeface (e.g. Swiss)

 		*/

 		EProportional = 1,

 		/** Typeface is a serif typeface (e.g. Times)

 		*/

 		ESerif = 2,

 		/** Typeface is a symbol typeface (e.g. Symbol)

 		*/

 		ESymbol = 4,

 		};

 public:

 	IMPORT_C TTypeface();

 	IMPORT_C TBool operator==(const TTypeface& aTypeface) const;

 	IMPORT_C void InternalizeL(RReadStream& aStream);

 	IMPORT_C void ExternalizeL(RWriteStream& aStream) const;

 	IMPORT_C void SetAttributes(TInt aAttributes);

 	IMPORT_C void SetIsProportional(TBool aIsProportional);

 	IMPORT_C void SetIsSerif(TBool aIsSerif);

 	IMPORT_C void SetIsSymbol(TBool aIsSymbol);

 	IMPORT_C TInt Attributes() const;

 	IMPORT_C TBool IsProportional() const;

 	IMPORT_C TBool IsSerif() const;

 	IMPORT_C TBool IsSymbol() const;

 	IMPORT_C void SetScriptTypeForMetrics(TLanguage aLanguage);

 	IMPORT_C void SetScriptTypeForMetrics(TInt aScript);

 	IMPORT_C TInt ScriptTypeForMetrics() const;

 	IMPORT_C void SetName(const TDesC& aName);

 	IMPORT_C const TDesC& Name() const;

 private:

 	void ResetAttributes();

 	void ResetScriptType();

 public:

 	/** The typeface name. */

     TBufC<KMaxTypefaceNameLength> iName;

 private:

     TUint32 iFlags;

     };

 /**

 An enumerated type for the format of a glyph bitmap. This type is currently 

 used to indicate whether glyph bitmaps for scalable fonts are drawn anti-aliased. 

 Additional values may be defined in the future.

 @see TFontStyle::SetBitmapType()

 @see CFbsTypefaceStore::SetDefaultBitmapType() 

 @publishedAll

 @released	

 */

 enum TGlyphBitmapType

 	{

 	/** The font store's default glyph bitmap format is used. */

 	EDefaultGlyphBitmap = 0,

 	/** The standard monochrome format: no anti-aliasing, 1 bit per pixel, 

 	run-length encoded. */

 	EMonochromeGlyphBitmap,

 	/** Standard 8-bits-per-pixel with anti-aliasing. */

 	EAntiAliasedGlyphBitmap,

 	/** The format used when sub-pixel font rendering is used. */

 	ESubPixelGlyphBitmap,

 	/** The format used when outline and shadow font rendering is used. 

 	If the raterizer supports the outline and shadow fonts, it will set the bitmaptype as 

 	EFourColourBlendGlyphBitmap but only when glyph bitmap type is set as EAntiAliasedGlyphBitmap and 

 	when any of the EDropShadow or EOutline effect is on. Only rasterizer providers can use this enum.

 	*/

 	EFourColourBlendGlyphBitmap,

 	/**

 	This is used for glyphs, and not fonts, and is needed to inform the font drawing routines

 	that the character should be drawn using the overall font setting. 

 	For Internal Use Only.

 	*/

 	EGlyphBitmapTypeNotDefined,

 	/**

 	This is used to inform the rasterizer that the best match should be

 	found for the bitmap type based upon its knowledge.

 	For Internal Use Only.

 	*/

 	EAntiAliasedOrMonochromeGlyphBitmap,

 	};

 /**

 Defines a set of font effects flags.

 @publishedAll 

 @released

 WARNING: This Class is for use by system/UI software ONLY.

 */

 NONSHARABLE_CLASS(FontEffect)

 	{

 public:

 	enum TEffect

 		{

 		ENone			= 0x0,		// No effects.

 		EAlgorithmicBold= 0x10,		// Font is algorithmic bold (a.k.a pseudo bold.)

 		EDropShadow		= 0x20,		// Font has a drop shadow.

 		EOutline		= 0x40,		// Font is an outline font.

 		EEmbossed		= 0x80,		// Font is embossed.

 		EEngraved		= 0x100,	// Font is engraved.

 		ESoftEdge		= 0x200,	// Font is soft edged.

 		EReserved1		= 0x400,	// Reserved for Symbian use.

 		EReserved2		= 0x800,	// Reserved for Symbian use.

 		EReserved3		= 0x1000,	// Reserved for Symbian use.

 		EReserved4		= 0x2000,	// Reserved for Symbian use.

 		EReserved5		= 0x4000,	// Reserved for Symbian use.

 		EReserved6		= 0x8000,	// Reserved for Symbian use.

 		};

 public:

 	IMPORT_C static TBool IsEffectOn(TEffect aEffect, TUint32 aFontEffect);

 	IMPORT_C static void SetEffect(TEffect aEffect, TBool aOn, TUint32& aFontEffect);

 	};

 /** Encapsulates a font style. 

 The font style information is comprised of:

 the posture of the font upright or italic

 the stroke weight of the font  normal or bold

 the print position of the font normal, subscript or superscript

 Note that the underline and strike-through attributes are not included in 

 this class, but are set in the graphics context.

 @see CGraphicsContext::SetUnderlineStyle()

 @see CGraphicsContext::SetStrikethroughStyle() 

 @publishedAll

 @released

 */

 class TFontStyle

 	{

 public:

 	IMPORT_C TFontStyle();

 	IMPORT_C TFontStyle(TFontPosture aPost,TFontStrokeWeight aStrWgt,TFontPrintPosition aPrintPos);

 	IMPORT_C void InternalizeL(RReadStream& aStream);

 	IMPORT_C void ExternalizeL(RWriteStream& aStream) const;

 	IMPORT_C TFontPosture Posture() const;

 	IMPORT_C TFontStrokeWeight StrokeWeight() const;

 	IMPORT_C TFontPrintPosition PrintPosition() const;

 	IMPORT_C void SetPosture(TFontPosture aPosture);

 	IMPORT_C void SetStrokeWeight(TFontStrokeWeight aStrokeWeight);

 	IMPORT_C void SetPrintPosition(TFontPrintPosition aPrintPosition);

 	inline TGlyphBitmapType BitmapType() const;

 	inline void SetBitmapType(TGlyphBitmapType aBitmapType);

 	IMPORT_C TBool operator==(const TFontStyle& aFontStyle) const;

 	IMPORT_C TUint32 Effects() const;

 	IMPORT_C TBool IsEffectOn(FontEffect::TEffect aEffect) const;

 	IMPORT_C void SetEffects(TUint32 aEffects);

 	IMPORT_C void SetEffects(FontEffect::TEffect aEffect, TBool aOn);

 private:

 	enum

 		{

 		EItalic=0x1,

 		EBold=0x2,

 		ESuper=0x4,

 		ESub=0x8

 		};

 private:

 	TUint32 iFlags; // bitmap type - 16 bits (high), font effects - 12 bits (middle), style - 4 bits (low)

 	TAny* iReserved1;

 	TAny* iReserved2;

 	};

 /**

 Specifies the font specification in device independent terms.

 @publishedAll 

 @released

 */

 class TFontSpec

 	{

 public:

 	IMPORT_C TFontSpec();

 	IMPORT_C TFontSpec(const TDesC& aTypefaceName,TInt aHeight);

 	IMPORT_C TBool operator==(const TFontSpec& aFontSpec) const;

 	IMPORT_C void InternalizeL(RReadStream& aStream);

 	IMPORT_C void ExternalizeL(RWriteStream& aStream) const;

 	IMPORT_C void SetScriptTypeForMetrics(TLanguage aLanguage);

 	IMPORT_C TInt ScriptTypeForMetrics() const;

 public:

 	/** The typeface. */

 	TTypeface iTypeface;

 	/** The height of the typeface (in twips). */

 	TInt iHeight;

 	/** The font style of the typeface. */

 	TFontStyle iFontStyle;

 	};

 /** Typeface family support information.

 This data-only class includes the name and attributes of a typeface, how many 

 font heights are available, its minimum and maximum heights, and whether or 

 not it is scaleable  a typeface is scaleable if it supports heights at 

 fixed intervals between the minimum and maximum heights. 

 @publishedAll 

 @released

 */

 class TTypefaceSupport

     {

 public:

 	/** The name and attributes of the typeface. */

     TTypeface iTypeface;

 	/** The number of distinct font heights available in the typeface. */

     TInt iNumHeights;

 	/** The typeface's minimum font height, in twips. */

     TInt iMinHeightInTwips;

 	/** The typeface's maximum font height, in twips. */

     TInt iMaxHeightInTwips;

 	/** Whether the typeface is scaleable. ETrue if it is scaleable, otherwise 

 	EFalse. */

     TBool iIsScalable; // supports heights from min to max at fixed interval

     };

 /**

 The percentage used to multiply a normal font height when calculating its 

 superscript or subscript height. 

 @publishedAll	

 @released

 */

 const TInt KSuperSubScalingPercentage=67;

 /**

 The percentage of a font height used to calculate its baseline offset for a 

 superscript print position. 

 @publishedAll	

 @released

 */

 const TInt KSuperscriptOffsetPercentage=-28;

 /**

 The percentage of a font height used to calculate its baseline offset for a 

 subscript print position. 

 @publishedAll	

 @released

 */

 const TInt KSubscriptOffsetPercentage=14;

 class CFont;

 /** Typeface store abstract base interface.

 This class provides the interface to a store for typefaces.

 See also CFontStore. 

 @publishedAll

 @released

 */

 class CTypefaceStore : public CBase

 	{

 public:

 	IMPORT_C ~CTypefaceStore();

 	/**

 	Gets the font which is the nearest to the given font specification.

 	When the font is no longer needed, call @c ReleaseFont().

 	Note that this deprecated function is replaced by the new @c GetNearestFontToDesignHeightInTwips() 

 	yielding (virtually) the same result. However clients are strongly encouraged to use the new

 	@c GetNearestFontToMaxHeightInTwips() function instead. This will guarantee that every 

 	character within any given text string will fit within the given amount of twips, whereas the design 

 	height is an aesthetic unit decided by the font designer without strict physical meaning, which 

 	may result in cropped characters.

 	@param aFont On return, contains a pointer to the nearest font.

 	@param aFontSpec The specification of the font to be matched.

 	@return KErrNone if successful; a system-wide error code otherwise.

 	@publishedAll

 	@deprecated Use GetNearestFontToDesignHeightInTwips

 	*/

 	virtual TInt GetNearestFontInTwips(CFont*& aFont, const TFontSpec& aFontSpec) = 0;

 	/**

 	Gets the font which is the nearest to the given font specification.

 	When the font is no longer needed, call @c ReleaseFont().

 	This new function replaces the deprecated @c GetNearestFontInTwips() yielding (virtually) the 

 	same result. However clients are strongly encouraged to use the new

 	@c GetNearestFontToMaxHeightInTwips() function instead. This will guarantee that every 

 	character within any given text string will fit within the given amount of twips, whereas the design 

 	height is an aesthetic unit decided by the font designer without strict physical meaning, which 

 	may result in cropped characters.

 	@param aFont On return, contains a pointer to the nearest font.

 	@param aFontSpec The specification of the font to be matched.

 	@return KErrNone if successful; a system-wide error code otherwise.

 	@publishedAll

 	@released

 	*/

 	virtual TInt GetNearestFontToDesignHeightInTwips(CFont*& aFont, const TFontSpec& aFontSpec) = 0;

 	/**

 	Gets the font which is the nearest to the given font specification.

 	When the font is no longer needed, call @c ReleaseFont().

 	The font and bitmap server returns a pointer to the nearest matching font 

 	from those available. Matches to max height of font - this does its best 

 	to return a font that will fit within the maximum height specified (but 

 	note that variations due to hinting algorithms may rarely result in this 

 	height being exceeded by up to one pixel). Problems can also be 

 	encountered with bitmap fonts where the typeface exists but doesn't have 

 	a font small enough.

 	@param aFont On return, contains a pointer to the nearest font.

 	@param aFontSpec The specification of the font to be matched.

 	@param aMaxHeight The maximum height within which the font must fit.

 	@return KErrNone if successful; a system-wide error code otherwise.

 	@publishedAll

 	@released

 	*/

 	virtual TInt GetNearestFontToMaxHeightInTwips(CFont*& aFont, const TFontSpec& aFontSpec, TInt aMaxHeight) = 0;

 	/** Gets the number of typefaces supported by the typeface store.

 	@return The number of supported typefaces. */

 	virtual TInt NumTypefaces() const=0;

 	/** Gets typeface information for a specified typeface index.

  	This information is returned in aTypefaceSupport, and

 	includes the typeface name and typeface attributes, the number of font

  	heights, the maximum and minimum font heights, and whether it is a

 	scaleable typeface.

  	@param aTypefaceSupport On return, if the function executed successfully, 

  	this object contains the typeface information.

   	@param aTypefaceIndex A typeface index number, in the range: zero to

              (NumTypefaces() - 1). */

 	virtual void TypefaceSupport(TTypefaceSupport& aTypefaceSupport,TInt aTypefaceIndex) const=0;

 	/** Gets the height of the font with specified height and typeface indices, 

 	in twips.

 	The value returned is rounded up or down to the nearest font height in twips.

 	@param aTypefaceIndex A typeface index number, in the range: 0 to 

 	(NumTypefaces() - 1). 

 	@param aHeightIndex A font height index number.

 	@return The height of the font, in twips. */

 	virtual TInt FontHeightInTwips(TInt aTypefaceIndex,TInt aHeightIndex) const=0;

 	IMPORT_C void ReleaseFont(CFont* aFont);

 	IMPORT_C static TInt BaselineOffset(TInt aHeight,TFontPrintPosition aPos);

 	IMPORT_C static TInt SuperSubHeight(TInt aHeight,TFontPrintPosition aPos);

 protected:

 	IMPORT_C CTypefaceStore();

 	IMPORT_C void ConstructL();

 	IMPORT_C void AddFontL(CFont* aFont);

 	IMPORT_C TBool IncrementFontCount(const CFont* aFont);

 private:

 	TBool FindFont(const CFont* aFont, TInt& aIdx) const;

 	NONSHARABLE_CLASS(TFontAccess)

 	/**

 	Pairs a font with a count of how many clients of the typeface store 

 	are accessing that font. 

     */

 		{

 	public:

 		/** A device specific font. */

 		CFont* iFont;

 		/** The number of clients accessing the font. */

 		TInt iAccessCount;

 		};

 protected:

 	/** A list of fonts accessed by clients of the typeface store, which pairs 

 	a font with a count of the number of clients accessing the font.

 	Implemented as an array of TFontAccess objects.

 	An object is added to this array for every font accessed. If the font is 

 	released by all clients, and the access count drops to zero, the font is 

 	removed from the list. */

 	CArrayFixFlat<TFontAccess>* iFontAccess;

 	};

 /** The maximum number of entries in the font cache.

 @see CFontCache */

 const TInt KMaxFontCacheEntries=32;

 /** Font cache. 

 When a CFont* needs to be found for a particular TFontSpec, the cache can 

 be searched to see if the TFontSpec is already in the cache. If the TFontSpec 

 is in the cache, its corresponding CFont* can be returned. Otherwise 

 GetNearestFontInTwips() must be used to search all of the available fonts for 

 the nearest CFont- a procedure which takes much longer than a simple cache

 search.

 The current font cache should be destroyed and a new cache created whenever 

 the zoom factor or device map changes, as these changes break the relation 

 between CFont and TFontSpec. 

 @publishedAll

 @released

 */

 class CFontCache : public CBase

 	{

 public:

 	IMPORT_C CFontCache();

 	IMPORT_C CFontCache(TInt aMaxEntries);

 	IMPORT_C ~CFontCache();

 	IMPORT_C CFont* Search(const TFontSpec& aFontSpec);

 	IMPORT_C CFont* AddEntryL(CFont* aFont,const TFontSpec& aFontSpec);

 	IMPORT_C CFont* RemoveFirstEntry();

 public:

 	/** The number of cache hits since the font cache was created i.e. 

 	successful results from CFontCache::Search(). */

 	TInt iNumHits;

 	/** The number of cache misses since the font cache was created i.e. 

 	unsuccessful results from CFontCache::Search(). */

 	TInt iNumMisses;

 private:

 	class CFontCacheEntry : public CBase

 		{

 	public:

 		CFontCacheEntry(CFont* aFont,const TFontSpec& aFontSpec,CFontCacheEntry* aNext);

 	public:

 		CFont* iFont;

 		TFontSpec iSpec;

 		CFontCacheEntry* iNext;

 		};

 private:

 	TInt iNumEntries;

 	TInt iMaxEntries;

 	CFontCacheEntry* iFirst;

 	};

 /** Interface class for mapping between twips and device-specific units (pixels).

 TZoomFactor is derived from MGraphicsDeviceMap.

 @see CGraphicsDevice

 @see TZoomFactor 

 @publishedAll

 @released

 */

 class MGraphicsDeviceMap

     {

 public:

 	IMPORT_C MGraphicsDeviceMap();

 	IMPORT_C virtual ~MGraphicsDeviceMap();

 	IMPORT_C TPoint TwipsToPixels(const TPoint& aTwipPoint) const;

 	IMPORT_C TRect TwipsToPixels(const TRect& aTwipRect) const;

 	IMPORT_C TPoint PixelsToTwips(const TPoint& aPixelPoint) const;

 	IMPORT_C TRect PixelsToTwips(const TRect& aPixelRect) const;

 	/** Converts a horizontal dimension from twips to pixels.

 	An implementation is supplied by a derived class.

 	@param aTwips A horizontal dimension of a device in twips. 

 	@return A horizontal dimension of a device in pixels. */

 	virtual TInt HorizontalTwipsToPixels(TInt aTwips) const=0;

 	/** Converts a vertical dimension from twips to pixels.

 	An implementation is supplied by a derived class.

 	@param aTwips A vertical dimension of a device in twips. 

 	@return A vertical dimension of a device in pixels. */

 	virtual TInt VerticalTwipsToPixels(TInt aTwips) const=0;

 	/** Converts a horizontal dimension from pixels to twips.

 	An implementation is supplied by a derived class.

 	@param aPixels A horizontal dimension of a device in pixels. 

 	@return A horizontal dimension of a device in twips. */

 	virtual TInt HorizontalPixelsToTwips(TInt aPixels) const=0;

 	/** Converts a vertical dimension from pixels to twips.

 	An implementation is supplied by a derived class.

 	@param aPixels A vertical dimension of a device in pixels. 

 	@return A vertical dimension of a device in twips. */

 	virtual TInt VerticalPixelsToTwips(TInt aPixels) const=0;

 	/**

 	Gets the font which is the nearest to the given font specification.

 	When the font is no longer needed, call @c ReleaseFont().

 	Note that this deprecated function is replaced by the new @c GetNearestFontToDesignHeightInTwips() 

 	yielding (virtually) the same result. However clients are strongly encouraged to use the new

 	@c GetNearestFontToMaxHeightInTwips() function instead. This will guarantee that every 

 	character within any given text string will fit within the given amount of twips, whereas the design 

 	height is an aesthetic unit decided by the font designer without strict physical meaning, which 

 	may result in cropped characters.

 	@param aFont On return, contains a pointer to the nearest font.

 	@param aFontSpec The specification of the font to be matched.

 	@return KErrNone if successful; a system-wide error code otherwise.

 	@publishedAll

 	@deprecated Use GetNearestFontToDesignHeightInTwips

 	*/

 	virtual TInt GetNearestFontInTwips(CFont*& aFont,const TFontSpec& aFontSpec)=0;

 	/**

 	Gets the font which is the nearest to the given font specification.

 	When the font is no longer needed, call @c ReleaseFont().

 	This new function replaces the deprecated @c GetNearestFontInTwips() yielding (virtually) the 

 	same result. However clients are strongly encouraged to use the new

 	@c GetNearestFontToMaxHeightInTwips() function instead. This will guarantee that every 

 	character within any given text string will fit within the given amount of twips, whereas the design 

 	height is an aesthetic unit decided by the font designer without strict physical meaning, which 

 	may result in cropped characters.

 	@param aFont On return, contains a pointer to the nearest font.

 	@param aFontSpec The specification of the font to be matched.

 	@return KErrNone if successful; a system-wide error code otherwise.

 	@publishedAll

 	@released

 	*/

 	virtual TInt GetNearestFontToDesignHeightInTwips(

 		CFont*& /*aFont*/, const TFontSpec& /*aFontSpec*/) { return KErrNotSupported; }

 	/**

 	Gets the font which is the nearest to the given font specification.

 	When the font is no longer needed, call @c ReleaseFont().

 	The font and bitmap server returns a pointer to the nearest matching font 

 	from those available. Matches to max height of font - this does its best 

 	to return a font that will fit within the maximum height specified (but 

 	note that variations due to hinting algorithms may rarely result in this 

 	height being exceeded by up to one pixel). Problems can also be 

 	encountered with bitmap fonts where the typeface exists but doesn't have 

 	a font small enough.

 	@param aFont On return, contains a pointer to the nearest font.

 	@param aFontSpec The specification of the font to be matched.

 	@param aMaxHeight The maximum height within which the font must fit.

 	This overrides the height specified in aFontSpec.

 	@return KErrNone if successful; a system-wide error code otherwise.

 	@publishedAll

 	@released

 	*/

 	virtual TInt GetNearestFontToMaxHeightInTwips(

 		CFont*& /*aFont*/, const TFontSpec& /*aFontSpec*/, TInt /*aMaxHeight*/) { return KErrNotSupported; }

 	/** Releases the specified font.

 	It is used to indicate that the specified font is no longer needed for use 

 	by the device map. As fonts can be shared between applications, this 

 	function does not delete the copy of the font from RAM unless the font was 

 	only being used by this particular device map.

 	An implementation is supplied by a derived class.

 	@param aFont A pointer to the font to be released. */

 	virtual void ReleaseFont(CFont* aFont)=0;

     };

 class CGraphicsContext;

 /** Specifies the interface for concrete device classes.

 It holds information on the capabilities and attributes of a graphics device. 

 The CBitmapDevice and CPrinterDevice classes are derived from CGraphicsDevice.

 @see CGraphicsDevice

 @see CPrinterDevice 

 @publishedAll

 @released

 */

 class CGraphicsDevice : public CBase , public MGraphicsDeviceMap

     {

 public:

 	/** Gets the display mode of the device.

 	@return The display mode of the device. */

 	virtual TDisplayMode DisplayMode() const=0;

 	/** Gets the size of the device area in pixels.

 	@return The width and height of the device area, in pixels */

 	virtual TSize SizeInPixels() const=0;

 	/** Gets the size of the device area in twips.

 	@return The width and height of the device area, in twips */

 	virtual TSize SizeInTwips() const=0;

  	/** Creates a graphics context for the device.

 	@param aGC On return, contains a pointer to the created graphics context. 

 	@return KErrNone, if successful; otherwise, another of the system-wide error 

 	codes. */

     virtual TInt CreateContext(CGraphicsContext*& aGC)=0;

 	/** Gets the number of typefaces supported by the graphics device.

 	@return The number of typefaces supported. */

     virtual TInt NumTypefaces() const=0;

  	/** Gets typeface information for a specified typeface.

 	This information is returned in aTypefaceSupport, and includes:

 	the typeface name and typeface attributes

 	the number of font heights

 	the maximum and minimum font heights

 	whether it is a scalable typeface

 	@param aTypefaceSupport On return, contains the typeface information. 

 	@param aTypefaceIndex A typeface index number, in the range: zero to 

 	(NumTypefaces() - 1). 

 	@see NumTypefaces() */

     virtual void TypefaceSupport(TTypefaceSupport& aTypefaceSupport,TInt aTypefaceIndex) const=0;

 	/** Get the height of a font in twips.

 	The font is identified by typeface and height.

 	The value returned is rounded up or down to the nearest font height in twips.

 	@param aTypefaceIndex An index identifying the typeface, in the range: 0 

 	to (NumTypefaces() - 1). 

 	@param aHeightIndex An index identifying the font height, in the range: 0 

 	to (iNumHeights - 1). Note that iNumHeights is in the TTypefaceSupport 

 	object returned by TypefaceSupport(). 

 	@return The height of the font, in twips. */

 	virtual TInt FontHeightInTwips(TInt aTypefaceIndex,TInt aHeightIndex) const=0;

 	/** Gets the palette attributes of the device.

 	@param aModifiable On return, holds information on whether or not the device's 

 	palette is modifiable (ETrue) or fixed (EFalse). 

 	@param aNumEntries On return, holds the number of entries in the device's 

 	palette. */

 	virtual void PaletteAttributes(TBool& aModifiable,TInt& aNumEntries) const=0;

 	/** Sets the device's palette.

 	Setting the palette is only possible if the device has a modifiable palette, 

 	which can be determined by calling PaletteAttributes().

 	@param aPalette The new palette for the device. */

 	virtual void SetPalette(CPalette* aPalette)=0;

 	/** Gets the device's current palette.

 	This function is only supported if the device has a modifiable palette, 

 	which can be determined by calling PaletteAttributes().

 	@param aPalette On return, holds the device's current palette.

 	@return KErrNone, if successful; otherwise, another of the system-wide error 

 	codes. */

 	virtual TInt GetPalette(CPalette*& aPalette) const=0;

     };

 /** 

 Code section range information. 

 A code section defines the bitmaps for characters in a specified range -

 the range is stored in objects of this type. 

 @publishedAll

 @deprecated 	This is not used anywhere in version 6.0.

 */

 class TCodeSection

 	{

 public:

 	/** The beginning of the range. */

 	TInt iStart;

 	/** The end of the range. */

 	TInt iEnd;

 	};

 /**

 WARNING: this Class is for internal use ONLY.  Compatibility is not guaranteed in future releases.

 UIDs corresponding to the CFont API extension functions

 @internalTechnology

 */

 const TUid KFontCapitalAscent	= {0x1020498E};

 const TUid KFontMaxAscent		= {0x10204B10};

 const TUid KFontStandardDescent	= {0x10204B11};

 const TUid KFontMaxDescent		= {0x10205AFC};

 const TUid KFontLineGap			= {0x10204B12};

 const TUid KFontGetFontTable    = {0x102872C1};

 const TUid KFontGetGlyphOutline = {0x102872C2};

 const TUid KFontReleaseGlyphOutline = {0x2002A1FD};

 const TUid KFontReleaseFontTable = {0x2002AC24};

 /** Abstract font interface.

 The CFont class provides a device-independent interface to a device-dependent 

 font usually obtained from a call to GetNearestFont...() on a graphics device. 

 It is used as a handle in CGraphicsContext::UseFont() and to obtain 

 device-dependent information about the font - notably the pixel width of a text 

 string.

 @see CFbsFont

 @see CGraphicsContext::UseFont() 

 @publishedAll 

 @released

 */

 class CFont : public CBase

 	{

 	friend class CTypefaceStore;

 public:

 	/** Text direction flags.

 	This enum is used in TMeasureTextInput and determines whether the text is 

 	drawn horizontally or vertically. Note: text is drawn vertically in some 

 	styles of Japanese, etc.

 	@see TMeasureTextInput */

 	enum TTextDirection

 		{

 	/** Text is drawn horizontally. */

  		/** Text is drawn horizontally. */

    		EHorizontal,

  		/** Text is drawn vertically. */

 		EVertical

 		};

 	/** Complicated parameter block used for contextual glyph selection, 

 	ligature creation and diacritic placement when drawing text in complex 

 	scripts

 	This class declares a constructor, another scoped class, and several other 

 	enums. However this class is unlikely to be useful to third party developers.

 	@see CFont::GetCharacterPosition()

 	@see CFont::GetCharacterPosition2()

 	@publishedAll

 	@released

 	*/

 	class TPositionParam

 		{

 	public:

 		/** Standard constructor. */

 		TPositionParam():

 			iDirection(EHorizontal),

 			iFlags(0),

 			iPosInText(0),

 			iOutputGlyphs(0)

 			{

 			}

 		enum

 			{

 			EMaxInputChars = 18,	// ligatures cannot be made from more than 18 components

 			EMaxOutputGlyphs = 8	// output can consist of up to 8 characters (one base and 7 combining characters)

 			};

 		/**Flags for TPositionParam::iFlags. */

 		enum TFlags

 			{

 			/** Input text is logically ordered not visually ordered. */

 			EFLogicalOrder = 1

 			};

 		/** Input: Orientation (EHorizontal or EVertical) in which to draw

 		the text. */

 		TInt16 iDirection;

 		/** Input: Flags from TFlags. */

 		TUint16 iFlags;

 		/** Input: Text containing the characters to be positioned. */

 		TPtrC iText;

 		/** Input and output: Position within iText to shape. On exit

 		it will index the first character not positioned */

 		TInt iPosInText;

 		/** Input and output: Pen position. */

 		TPoint iPen;			

 		/** Output of GetCharacterPosition and GetCharacterPosition2.

 		@see CFont::GetCharacterPosition

 		@see CFont::GetCharacterPosition2

 		@publishedAll

 		@released */

 		class TOutput

 			{

 		public:

 			/** Standard constructor. */

 			TOutput() : iBitmapSize(TSize::EUninitialized),

 				iBounds(TRect::EUninitialized) {}

 			/** Character or glyph code. */

 			TUint iCode;			

 			/** Bitmap data for the glyph, if available */

 			const TUint8* iBitmap;	

 			/** Size of the bitmap before algorithmic bolding, size 

 			multiplication, etc. */

 			TSize iBitmapSize;		

 			/** Bitmap bounds relative to the original pen position. */

 			TRect iBounds;			

 			};

 		/** Information about the glyphs that were output. */

 		TOutput iOutput[EMaxOutputGlyphs];	

 		/** Number of glyphs actually output. */

 		TInt iOutputGlyphs;					

 		};	

 	/** Input parameter block.

 	This is optionally used by CFont::MeasureText(), which is the powerful text 

 	measurement function underlying all the other text measurement functions.

 	@see CFont::MeasureText() 

 	@publishedAll

 	@released

 	*/

 	class TMeasureTextInput

 		{

 	public:

 		TMeasureTextInput():

 			iStartInputChar(0),

 			iEndInputChar(KMaxTInt),

 			iDirection(EHorizontal),

 			iFlags(0),

 			iMaxAdvance(KMaxTInt),

 			iMaxBounds(KMaxTInt),

 			iCharJustNum(0),

 			iCharJustExcess(0),

 			iWordJustNum(0),

 			iWordJustExcess(0)

 			{

 			}

 		/**Flags for TMeasureTextInput::iFlags. */

 		enum TFlags

 			{

  			/** Input text is visually ordered left-to-right. */

  			EFVisualOrder = 1,

  			/** Input text is visually ordered right-to-left.

  			Overrides EFVisualOrder. */

  			EFVisualOrderRightToLeft = 2,

  			/** Flag to consider side bearings when checking bounds for line-break */

  			EFIncludePenPositionInBoundsCheck = 4

 			};

 		/** Starting index specifying first input character in iText.

 		Together with iEndInputChar, this allows some context before and 

 		after the measured text to be supplied so that shaping can work 

 		properly. */

 		TInt iStartInputChar;	

 		/** Index specifying the final input character.

 		Together with iStartInputChar, this allows some context before and 

 		after the measured text to be supplied so that shaping can work 

 		properly. */

 		TInt iEndInputChar;		

 		/** The direction in which to draw the text. */

 		TUint16 iDirection;

 		/** Flags from TFlags. */

 		TUint16 iFlags;

 		/** The maximum advance. */

 		TInt iMaxAdvance;		

 		/** The maximum width (or height if drawing vertically) of bounds. */

 		TInt iMaxBounds;		

 		/** The number of glyph groups to be letter-spaced. */

 		TInt iCharJustNum;		

 		/** The amount of space to be used for letter spacing. */

 		TInt iCharJustExcess;	

 		/** The number of spaces to be used for word spacing. */

 		TInt iWordJustNum;		

 		/** The amount of space to be used for word spacing. */

 		TInt iWordJustExcess;	

 		};

 	/** Output parameter block.

 	This is optionally used by CFont::MeasureText(), which is the powerful text 

 	measurement function underlying all the other text measurement functions.

 	@see CFont::MeasureText() 

 	@publishedAll

 	@released

 	*/

 	class TMeasureTextOutput

 		{

 		public:

 		/** The number of input characters that would be drawn.

 		This may be less than the length of the text if a maximum advance or bounding 

 		box size is specified. */

 		TInt iChars;			

 		/** The number of glyphs that would be drawn. */

 		TInt iGlyphs;			

 		/** The number of groups that would be drawn.

 		A group is a base glyph plus one or more combining characters. */

 		TInt iGroups;			

 		/** The number of word spaces (U+0020) that would be drawn. */

 		TInt iSpaces;			

 		/** The bounding box of all the glyphs that would be drawn. */

 		TRect iBounds;			

 		/** The maximum width and height of any glyph. */

 		TSize iMaxGlyphSize;	

 		};

 	/**

 	Data availability flags.

 	Some fonts like printer fonts may only have width information and can return 

 	ECharacterWidthOnly to show this: the text drawing routines in CFont synthesize 

 	the rest of the data if necessary.

 	@see GetCharacterData() 

 	@publishedAll	

 	@released

 	*/

 	enum TCharacterDataAvailability

 		{

 		/** No font information available. */

 		ENoCharacterData,

 		/** Width information only is available. */

 		ECharacterWidthOnly,

 		/** All character data is available. */

 		EAllCharacterData

 		};

 private:

 	// virtual functions have been made protected and public non-virtual ones

 	// added to convert CFont to a handle-body pattern. SC is kept throught the

 	// new functions and BC is kept by keeping the protected functions in the

 	// same place in the class, and therefore in the same place in the vtable

 	/**

 	@publishedAll

 	WARNING: Function for internal use ONLY.  Compatibility is not guaranteed in future releases. Please see derived class for implementation.

 	*/

 	virtual TUid DoTypeUid() const=0;

 	/**

 	@publishedAll

 	WARNING: Function for internal use ONLY.  Compatibility is not guaranteed in future releases. Please see derived class for implementation.

 	*/

 	virtual TInt DoHeightInPixels() const=0;

 	/**

 	@publishedAll

 	WARNING: Function for internal use ONLY.  Compatibility is not guaranteed in future releases. Please see derived class for implementation.

 	*/

 	virtual TInt DoAscentInPixels() const=0;

 	IMPORT_C virtual TInt DoDescentInPixels() const;

 	/**

 	@publishedAll

 	WARNING: Function for internal use ONLY.  Compatibility is not guaranteed in future releases. Please see derived class for implementation.

 	*/

 	virtual TInt DoCharWidthInPixels(TChar aChar) const=0;

 	/**

 	@publishedAll

 	WARNING: Function for internal use ONLY.  Compatibility is not guaranteed in future releases. Please see derived class for implementation.

 	*/

 	virtual TInt DoTextWidthInPixels(const TDesC& aText) const=0;

 	/**

 	@publishedAll

 	WARNING: Function for internal use ONLY.  Compatibility is not guaranteed in future releases. Please see derived class for implementation.

 	*/

 	virtual TInt DoBaselineOffsetInPixels() const=0;

 	/**

 	@publishedAll

 	WARNING: Function for internal use ONLY.  Compatibility is not guaranteed in future releases. Please see derived class for implementation.

 	*/

 	virtual TInt DoTextCount(const TDesC& aText,TInt aWidthInPixels) const=0;

 	/**

 	@publishedAll

 	WARNING: Function for internal use ONLY.  Compatibility is not guaranteed in future releases. Please see derived class for implementation.

 	*/

 	virtual TInt DoTextCount(const TDesC& aText,TInt aWidthInPixels,TInt& aExcessWidthInPixels) const=0;

 	/**

 	@publishedAll

 	WARNING: Function for internal use ONLY.  Compatibility is not guaranteed in future releases. Please see derived class for implementation.

 	*/

 	virtual TInt DoMaxCharWidthInPixels() const=0;

 	/**

 	@publishedAll

 	WARNING: Function for internal use ONLY.  Compatibility is not guaranteed in future releases. Please see derived class for implementation.

 	*/

 	virtual TInt DoMaxNormalCharWidthInPixels() const=0;

 	/**

 	@publishedAll

 	WARNING: Function for internal use ONLY.  Compatibility is not guaranteed in future releases. Please see derived class for implementation.

 	*/

 	virtual TFontSpec DoFontSpecInTwips() const=0;

 protected:	

 	IMPORT_C virtual TCharacterDataAvailability DoGetCharacterData(TUint aCode, TOpenFontCharMetrics& aMetrics,const TUint8*& aBitmap,TSize& aBitmapSize) const;

 	IMPORT_C virtual TBool DoGetCharacterPosition(TPositionParam& aParam) const;

 	IMPORT_C virtual TInt DoExtendedFunction(TUid aFunctionId, TAny* aParam = NULL) const;

 protected:

 	IMPORT_C virtual ~CFont();

 public:

 	inline TInt FontCapitalAscent() const;

 	inline TInt FontMaxAscent() const;

 	inline TInt FontStandardDescent() const;

 	inline TInt FontMaxDescent() const;

 	inline TInt FontLineGap() const;

 	inline TInt FontMaxHeight() const;

 public:

 	/** Gets run-time identity of the actual font type. This enables safe casting to 

 	a derived type.

 	For example, if the derived type is a CFbsFont, the return value is KCFbsFontUid. 

 	You would need to cast to a CFbsFont to get a character bounding box. Similarly, 

 	a CBitmapFont returns KCBitmapFontUidVal.

 	@return The font-type identifier. */

 	IMPORT_C TUid TypeUid() const;

 	/** Gets the font height in pixels.

 	Note that this deprecated function is replaced by the new @c FontMaxHeight().

 	@return The font height in pixels.

 	@see FontMaxHeight()

 	@deprecated */

 	IMPORT_C TInt HeightInPixels() const;

 	/** Gets the font ascent in pixels.

 	Note that this deprecated function is replaced by the new @c FontMaxAscent()

 	or in some cases @c FontCapitalAscent().	

 	@return The font ascent in pixels.

 	@see FontCapitalAscent()

 	@see FontMaxAscent()

 	@deprecated */

 	IMPORT_C TInt AscentInPixels() const;

 	/** Gets the font descent in pixels.

 	Note that this deprecated function is replaced by the new @c FontMaxDescent()

 	or in some cases @c FontStandardDescent().	

 	@return The font descent in pixels.

 	@see FontStandardDescent() 

 	@see FontMaxDescent()

 	@deprecated */

 	IMPORT_C TInt DescentInPixels() const;

 	/** Gets the width in pixels in this font of the specified character.

 	Note: For OpenType fonts this function returns the horizontal advance of

 	the character, which may be different from the actual width.

 	@param aChar The character whose width should be determined. 

 	@return The width in pixels of the specified character in this font. */

 	IMPORT_C TInt CharWidthInPixels(TChar aChar) const;

 	/** Gets the width in pixels of the specified descriptor when displayed in this 

 	font.

 	@param aText The descriptor whose width should be determined. 

 	@return The width of the specified descriptor when displayed in this font, 

 	in pixels. */

 	IMPORT_C TInt TextWidthInPixels(const TDesC& aText) const;

 	/** Gets the baseline offset in pixels. 

 	The baseline offset is how far a font is raised or lowered from its normal 

 	baseline.

 	@return Offset from normal baseline, in pixels. */

 	IMPORT_C TInt BaselineOffsetInPixels() const;

 	/** Gets how much of the specified descriptor can be displayed in this font without 

 	exceeding the specified width.

 	Note:

 	This function does not display any of the descriptor itself - it is used 

 	before display, to test whether the whole descriptor can be displayed.

 	@param aText The descriptor. 

 	@param aWidthInPixels The available width for character display. 

 	@return The number of characters which will be able to be displayed without 

 	exceeding the specified width. The count starts from the beginning of the 

 	descriptor. */

 	IMPORT_C TInt TextCount(const TDesC& aText,TInt aWidthInPixels) const;

 	/** Gets how much of the specified descriptor can be displayed in this font without 

 	exceeding the specified width. 

 	It also returns the excess width - defined as the specified available width 

 	minus the width of the portion of the descriptor which can be displayed without 

 	exceeding the available width.

 	@param aText The descriptor. 

 	@param aWidthInPixels The available width for character display. 

 	@param aExcessWidthInPixels The excess width after displaying the portion of 

 	the descriptor, in pixels. 

 	@return The number of characters which will be able to be displayed without 

 	exceeding the specified width. The count starts from the beginning of the 

 	descriptor. */

 	IMPORT_C TInt TextCount(const TDesC& aText,TInt aWidthInPixels,TInt& aExcessWidthInPixels) const;

 	/** Gets the width in pixels of the widest character in this font.

 	@return The width of the maximum width character, in pixels. */

 	IMPORT_C TInt MaxCharWidthInPixels() const;

 	/** Gets the width in pixels of the widest normal character in this font.

 	Normal characters include all character in a character set except non-alphabetic 

 	characters (e.g. the copyright symbol, or a block graphics symbol, for example).

 	@return The width of the maximum width normal character, in pixels. */

 	IMPORT_C TInt MaxNormalCharWidthInPixels() const;

 	/** Gets the font specification of this font in twips.

 	@return The font specification of this font (in twips). */

 	IMPORT_C TFontSpec FontSpecInTwips() const;

 	IMPORT_C TCharacterDataAvailability GetCharacterData(TUint aCode, TOpenFontCharMetrics& aMetrics,const TUint8*& aBitmap,TSize& aBitmapSize) const;

 	IMPORT_C TBool GetCharacterPosition(TPositionParam& aParam) const;

 	IMPORT_C TInt WidthZeroInPixels() const;

 	IMPORT_C TInt MeasureText(const TDesC& aText, const TMeasureTextInput* aInput = NULL, TMeasureTextOutput* aOutput = NULL) const;

 	IMPORT_C static TBool CharactersJoin(TInt aLeftCharacter, TInt aRightCharacter);

 	IMPORT_C TInt ExtendedFunction(TUid aFunctionId, TAny* aParam = NULL) const;

 	IMPORT_C TBool GetCharacterPosition2(TPositionParam& aParam, RShapeInfo& aShapeInfo) const;

 	/** Gets the width in pixels of the specified descriptor when displayed in this 

 	font.

 	@param aText The descriptor whose width should be determined.

 	@param aParam Parameter block that controls how much of aText is measured

 	@return The width of the specified descriptor when displayed in this font, 

 	in pixels. */

 	IMPORT_C TInt TextWidthInPixels(const TDesC& aText,const TMeasureTextInput* aParam) const;

 	};

 class CFbsBitmap;

 class CWsBitmap;

 /** Abstract base class for all graphics contexts.

 Created by a CGraphicsDevice.

 Provides the 'context' in which you are drawing to an associated device, in 

 the sense that it holds the settings for drawing, such as the pen and brush 

 settings (e.g. color, line styles) and the font settings (e.g. bold, underline, 

 italic). These settings are device-independent.

 Also provides the clipping region (the visible drawing area).

 The settings and clipping area can be updated while drawing.

 This class also contains the main drawing functions, and all drawing is done 

 through a CGraphicsContext.

 The graphics context deals with pixels of device-dependent size and uses fonts 

 with device-dependent size and representation. The sizes and fonts to be passed 

 to the class functions therefore need to be converted from size-independent 

 units to size-dependent units first. This is done by an MGraphicsDeviceMap 

 derived class. This may be a TZoomFactor or the CGraphicsDevice.

 See CGraphicsContext::Reset() for the default graphics context settings immediately 

 after construction.

 @see CBitmapContext 

 @publishedAll

 @released

 */

 class CGraphicsContext : public CBase

 	{

 public:

 	/** Text alignment.

 	@publishedAll

 	@released

 	*/

 	enum TTextAlign

 		{

 		/** Text is left-aligned. */

 		ELeft,

 		/** Text is centred. */

 		ECenter,

 		/** Text is right-aligned. */

 		ERight

 		};

 	/** 

 	Drawing mode components.

 	This enum is not intended to be used directly, but provides components for 

 	the easy specification of drawing modes in the TDrawMode enum. 

 	@publishedAll

 	@released

 	*/

 	enum TDrawModeComponents

 		{

 		/** 1 */

 		EInvertScreen=1,

 		/** 2 */

 		EXor=2,

 		/** 4 */

 		EOr=4,

 		/** 8 */

 		EAnd=8,

 		/** 14 */

 		ELogicalOp=14,

 		/** 16 */

 		EInvertPen=16,

 		/** 32 */

 		EPenmode=32,

 		/** 64 */

 		EWriteAlpha=64,

 		};

 	/** 

 	Drawing modes.

 	This enum builds on the drawing mode components in the TDrawModeComponents 

 	enum.

 	If the pen colour is p, brush colour is b and screen colour is s, the effect 

 	of TDrawMode::EDrawModeAND is P=p&s and B=b&s. In other words, the effective 

 	colour of the pen on the screen, P, is that produced by the bitwise ANDing 

 	of the current screen colour and the current pen colour. The effect is similar 

 	for the effective brush colour, B.

 	The effective pen and brush colour are given in the table using the key

 	Inputs: pen colour is p, brush colour is b and screen colour is s

 	Outputs: effective brush colour is B, effective pen colour is P. 

 	Some notes on using EDrawModeWriteAlpha:-

 	- It is rare for client code to need to use this draw mode: see the documentation

 	of SetDrawMode() for more information.

 	- EDrawModeWriteAlpha should only be used with DrawRect(), Clear(), BitBlt(), and BitBltMasked() 

 	with EGray2 mask (and DrawBitmap() and DrawBitmapMasked()). For other draw operations, it is not 

 	supported, and may have unintended effects.

 	- EDrawModeWriteAlpha has the same effect as EDrawModePEN, unless the brush colour has transparency 

 	(DrawRect(), Clear()), or the source bitmap is EColor16MA (and has transparency) (BitBlt(), BitBltMasked())

 	- EDrawModeWriteAlpha has the same effect as EDrawModePEN if the draw mode of the destination does not 

 	support alpha blending. (Blending is only supported in 24bpp and 32bpp colour i.e. EColor16M, EColor16MU, EColor16MA)

 	- In these cases, EDrawModePEN does alpha blending, whereas EDrawModeWriteAlpha means don't do alpha blending.

 	@see SetDrawMode()

 	@publishedAll

 	@released

 	*/

 	enum TDrawMode

 		{

 		/** Bitwise ANDs the pen and brush colours with the screen colour. 

 		P=p&s, B=b&s */

 		EDrawModeAND=EAnd,

 		/** Inverts the pen and brush colours before ANDing. P=(~p)&s, 

 		B=(~b)&s */

 		EDrawModeNOTAND=EInvertScreen|EAnd,

 		/** Uses both pen and brush colour as they are. P=p, B=b */

 		EDrawModePEN=EPenmode,

 		/** Inverts the screen colour before ANDing. P=p&(~s), B=b&(~s) */

 		EDrawModeANDNOT=EAnd|EInvertPen,

 		/** Bitwise XORs the pen and brush colours with the screen colour. 

 		P=p^s, B=b^s */

 		EDrawModeXOR=EXor,

 		/** Bitwise ORs the pen and brush colours with the screen colour. 

 		P=p|s, B=b|s */

 		EDrawModeOR=EOr,

 		/** Inverts the screen and pen and brush colours before ANDing. 

 		P=(~p)&(~s), B=(~b)&(~s) */

 		EDrawModeNOTANDNOT=EInvertScreen|EAnd|EInvertPen,

 		/** Inverts the pen and brush colours before XORing. P=(~p)^s, 

 		B=(~b)^s */

 		EDrawModeNOTXOR=EInvertScreen|EXor,

 		/** Inverts the colour of each pixel that is drawn over, (pen and 

 		brush attributes are ignored). P=~s, B=~s */

 		EDrawModeNOTSCREEN=EInvertScreen,

 		/** Inverts the screen colour before ORing. P=p|(~s), 

 		B=b|(~s) */

 		EDrawModeNOTOR=EInvertScreen|EOr,

 		/** Inverts the pen and brush colours. P=~p, B=~b */

 		EDrawModeNOTPEN=EInvertPen|EPenmode,

 		/** Inverts the pen and brush colours before ORing. P=(~p)|s, 

 		B=(~b)|s */

 		EDrawModeORNOT=EOr|EInvertPen,

 		/** Inverts the screen and pen and brush colours before ORing.

 		P=(~p)|(~s), B=(~b)|(~s) */

 		EDrawModeNOTORNOT=EInvertScreen|EOr|EInvertPen,

 		/** Writes alpha information in the source directly into the destination, rather than blending. */

 		EDrawModeWriteAlpha=EWriteAlpha,

 		};

 	/** 

 	Pen styles. The screen pattern unit in each definition below describes the 

 	pattern drawn by the line 1 represents a pixel drawn, 0 represents a 

 	pixel that is not affected. 

 	@publishedAll

 	@released

 	*/

 	enum TPenStyle

 		{

 		/** The pen does not draw. Screen pattern unit = 00... */

 		ENullPen,

 		/** A solid line (default). Screen pattern unit = 11... */

 		ESolidPen,

 		/** A dotted line. Screen pattern unit = 1000... */

 		EDottedPen,

 		/** A dashed line. Screen pattern unit = 111000... */

 		EDashedPen,

 		/** A line of alternating dashes and dots. Screen pattern unit = 

 		1111001100... */

 		EDotDashPen,

 		/** A line of alternating single dashes and pairs of dots. Screen 

 		pattern unit = 11110011001100... */

 		EDotDotDashPen

 		};

 	/** 

 	Brush styles. 

 	@publishedAll

 	@released

 	*/

 	enum TBrushStyle

 		{

 		/** The brush fill has no effect (default). */

 		ENullBrush,

 		/** The brush fills with a solid single colour, determined by 

 		SetBrushColor() and the drawing mode. */

 		ESolidBrush,

 		/** The brush fills with a selected bitmap pattern, set by 

 		UseBrushPattern(). */

 		EPatternedBrush,

 		/** The brush fills with vertical hatching  lines going from top to 

 		bottom. */

 		EVerticalHatchBrush,

 		/** The brush fills with diagonal hatching lines going from bottom 

 		left to top right. */

 		EForwardDiagonalHatchBrush,

 		/** The brush fills with horizontal hatching  lines going from left 

 		to right. */

 		EHorizontalHatchBrush,

 		/** The brush fills with rearward diagonal hatching lines going from top 

 		left to bottom right. */

 		ERearwardDiagonalHatchBrush,

 		/** The brush fills with horizontal and vertical hatching  lines going 

 		from left to right plus lines going from top to bottom  giving the 

 		effect of a grid of small squares */

 		ESquareCrossHatchBrush,

 		/** The brush fills with forward diagonal and rearward diagonal hatching 

 		lines going from bottom left to top right plus lines going from top left 

 		to bottom right giving the effect of a grid of small diamonds. */

 		EDiamondCrossHatchBrush

 		};

 	/** 

 	Rules used to fill self crossing polygons. 

 	The filling of a polygon proceeds as follows: for a given point in the 

 	polygon, then

 	if the rule is TFillRule::EAlternate (default) and it has an odd winding 

 	number, then fill the surrounding area.

 	if the rule is TFillRule::EWinding and it has a winding number greater than 

 	zero, then fill the surrounding area. 

 	@publishedAll

 	@released

 	*/

 	enum TFillRule

 		{

 		/** Only fill areas with odd winding numbers. */

 		EAlternate,

 		/** Fill areas with winding numbers greater than zero. */

 		EWinding

 		};

 	/** Parameters to control the drawing of text. */

 	struct TDrawTextParam

 		{

 	public:

 		TDrawTextParam():

 			iDirection(CFont::EHorizontal),

 			iCharJustNum(0),

 			iCharJustExcess(0),

 			iWordJustNum(0),

 			iWordJustExcess(0)

 	/** Reserved for future use. */

 			{}

 	public:

 		/** the direction in which to draw the text. */

 		CFont::TTextDirection iDirection;	

 		/** number of glyph groups to be letterspaced */

 		TInt iCharJustNum;					

 		/** amount of space to be used for letterspacing */

 		TInt iCharJustExcess;				

 		/** number of spaces to be used for wordspacing*/

 		TInt iWordJustNum;					

 		/**  amount of space to be used for wordspacing*/

 		TInt iWordJustExcess;				

 		};

 	/** Parameters for extended text drawing and measuring. It is used by 

 	CGraphicsContext::DrawTextExtended() to indicate whether text should be 

 	drawn from right-to-left or left-to-right. */

 	struct TDrawTextExtendedParam : public TDrawTextParam

 		{

 	public:

 		/** Constructor. Initialises iParRightToLeft to EFalse. */

 		TDrawTextExtendedParam():

 			iParRightToLeft(EFalse)

 			{}

 	public:

 		/** ETrue if the text direction is right-to-left (for scripts like 

 		Arabic and Hebrew). EFalse if left-to-right. */

 		TBool iParRightToLeft;	

 		};

 	/**

 	Parameters used in drawing text within supplied context.

 	It is used by CGraphicsContext::DrawText() and CGraphicsContext::DrawTextVertical() family of API's

 	to draw text from iStart to iEnd withing the supplied text descriptor.

 	*/

 	class TTextParameters

 		{

 	public:

 		TTextParameters():

 			iStart(0),

 			iEnd(KMaxTInt),

 			iFlags(0)

 				{

 				}

 		TInt iStart;

 		TInt iEnd;

 		TUint16 iFlags;

 		/* Reserved for future use */

 		TAny* iReserved1;

 		TAny* iReserved2;

 		TAny* iReserved3;

 		TAny* iReserved4;

 		};

 public:

 	/** Gets a pointer to the graphics context's graphics device.

 	@return A pointer to the graphics device. */

 	virtual CGraphicsDevice* Device() const=0;

 	/** Sets the position of the co-ordinate origin.

 	All subsequent drawing operations are done relative to this origin.

 	@param aPos The origin. The default origin is TPoint(0,0) the top left 

 	corner of the screen. */

 	virtual void SetOrigin(const TPoint& aPos=TPoint(0,0))=0;

 	/** Sets the drawing mode. 

 	The way that the pen and brush draw depends on the drawing mode. The drawing 

 	mode affects the colour that is actually drawn, because it defines the way 

 	that the current screen colour logically combines with the current pen colour 

 	and brush colour. There are many drawing modes, each giving different logical 

 	combinations of pen, brush and screen colours. Each mode is produced by ORing 

 	together different combinations of seven drawing mode components.

 	The three most important modes are TDrawMode::EDrawModePEN, TDrawMode::EDrawModeNOTSCREEN 

 	and TDrawMode::EDrawModeXOR. The default drawing mode is TDrawMode::EDrawModePEN.

 	The drawing mode is over-ridden for line and shape drawing functions when 

 	a wide pen line has been selected. It is forced to TDrawMode::EDrawModePEN. 

 	This is to prevent undesired effects at line joins (vertexes).

 	Notes:

 	TDrawMode::EDrawModeAND gives a "colour filter" effect. For example:

 	- ANDing with white gives the original colour

 	- ANDing with black gives black

 	TDrawMode::EDrawModeOR gives a "colour boost" effect. For example:

 	- ORing with black gives the original colour

 	- ORing with white gives white

 	TDrawMode::EDrawModeXOR gives an "Exclusive OR" effect. For example:

 	- white XOR black gives white

 	- white XOR white gives black

 	- black XOR black gives black

 	TDrawMode::EDrawModeWriteAlpha should not normally need to be used by client code. 

 	The following are exceptions:-

 	- When a client side EColor16MA bitmap needs to have a transparent background 

 	(because you are intending to blend it onto something else), then you need to set 

 	EDrawModeWriteAlpha to Clear() it.

 	- When you want to BitBlt() with an EColor16MA source bitmap that is opaque everywhere, 

 	then using EDrawModeWriteAlpha is more efficient than EDrawModePEN, because the bitmap 

 	does not need to be blended. 

 	Note that if you have a transparent brush or source bitmap and you are drawing to a window, 

 	then it is a defect to use EDrawModeWriteAlpha.

 	@param aDrawingMode The drawing mode.

 	@see CGraphicsContext::TDrawMode

 	@see CGraphicsContext::TDrawModeComponents */

 	virtual void SetDrawMode(TDrawMode aDrawingMode)=0;

 	/** Sets the clipping rectangle.	 

 	The area of visible drawing depends on the clipping rectangle, any items 

 	that fall outside the extent of the clipping rectangle will not be drawn. 

 	The default clipping rectangle is the full device area.

 	Note that clipping is additive. If a clipping region has been set using SetClippingRegion() 

 	then clipping will be to the intersection of that region and this rectangle.

 	@param aRect The rectangle to be used as the clipping rectangle. Note that 

 	this rectangle is tranformed by the current co-ordinate origin before it is used. 

 	The co-ordinate origin is set using SetOrigin().

 	@see CGraphicsContext::SetClippingRegion() 

 	@see CGraphicsContext::SetOrigin() */

 	virtual void SetClippingRect(const TRect& aRect)=0;

 	/** Cancels any clipping rectangle.

 	Clipping thus reverts to the full device area, the default.

 	@see SetClippingRect() */

 	virtual void CancelClippingRect()=0;

 	/** Resets the graphics context to its default settings:

 	the drawing mode is TDrawMode::EDrawModePen (pen and brush colours used as 

 	they are)

 	there is no clipping rectangle

 	the pen settings are: black, solid, single pixel size

 	the brush style is null

 	no text font is selected */

 	virtual void Reset()=0;

    /** Sets the device font to be used for text drawing.

 	If the font is already in memory, then that copy is shared.

 	Notes:

 	The CFont* argument must have been previously initialised by calling 

 	MGraphicsDeviceMap::GetNearestFontInTwips() with the required 

 	font-specification. If the CFont* has not been initialised 

 	correctly, and therefore does not point to an available font-bitmap, 

 	then a panic is raised.

 	When the font is no longer required, use DiscardFont() to free up the 

 	memory used. If UseFont() is used again without using DiscardFont() then 

 	the previous font is discarded automatically.

 	If no font has been selected, and an attempt is made to draw text with 

 	DrawText(), then a panic is raised.

 	@param aFont A device font 

 	@see MGraphicsDeviceMap::GetNearestFontInTwips() */

 	virtual void UseFont(const CFont* aFont)=0;

 	/** Discards a font.

 	This frees up the memory used, if the font is not being shared.

 	The function can be called when no font is in use. */

 	virtual void DiscardFont()=0;

 	/** Sets the underline style.

 	This is applied to all subsequently drawn text.

 	@param aUnderlineStyle The underline style on or off. */

 	virtual void SetUnderlineStyle(TFontUnderline aUnderlineStyle)=0;

 	/** Sets the strikethrough style.

 	This is applied to all subsequently drawn text.

 	@param aStrikethroughStyle The strikethrough style on or off. */

 	virtual void SetStrikethroughStyle(TFontStrikethrough aStrikethroughStyle)=0;

 	IMPORT_C static TInt JustificationInPixels(TInt aExcessPixels,TInt aTotalUnits,TInt aFirstUnit,TInt aNumUnits);

 	IMPORT_C static TInt JustificationInPixels(TInt& aExcessPixels,TInt& aTotalUnits);

 	/** Adjusts the spaces between words to stretch or squeeze to a certain 

 	width.

 	The function is required by the Text Views API, and is not intended for 

 	regular use by developers.

 	The text line that is to be justified has a certain number of gaps (spaces) 

 	between the words. It also has a distance (in pixels) between the end of 

 	the last word and the actual end of the line (right hand margin, usually). 

 	These excess width pixels are distributed amongst the gaps between the words 

 	to achieve full justification of the text line. Spaces become fat spaces to 

 	keep underlining/strikethrough consistent. Pixels are distributed to the 

 	inter-word gaps starting from the left end of the string. The spacing 

 	between characters in each word remains unchanged.

 	After a call to SetWordJustification(), subsequent calls to either of the 

 	two DrawText() functions are affected until the number of spaces specified 

 	by aNumSpaces is used up.

 	The easiest way to find out the excess width and number of spaces is to call 

 	CFont::MeasureText(). This function can also perform counting, which is 

 	finding how much of some text will fit into a given width.

 	Use CFont::TextCount() to return the excess width.

 	For example, in the string "To be, or not to be", there are five inter-word 

 	gaps. If there are six excess pixels they will be distributed in the 

 	proportion 	2, 1, 1, 1, 1 between the words. If there are nine excess pixels 

 	they will be distributed in the proportion 2, 2, 2, 2, 1 between the words.

 	Notes:

 	If the excess width is zero, then calling SetWordJustification() has no 

 	effect.

 	At first sight it may appear that SetWordJustification() is not required 

 	because you can simply call DrawText() for each word. However, underlined 

 	justified text does not work using this strategy  you get a non-underlined 

 	gap between the space and the beginning of the next word.

 	@param aExcessWidth The width (in pixels) to be distributed between the 

 	specified number of spaces. 

 	@param aNumGaps The number of word spaces (characters with the code U+0020) 

 	over which the change in width is distributed. */

 	virtual void SetWordJustification(TInt aExcessWidth,TInt aNumGaps)=0;

 	/** Sets character justification.

 	This function is required by the Text Views API, and is not intended for 

 	regular use by developers.

 	It affects the strings of text used in the calls to DrawText() that follow, 

 	until the number of characters drawn equals aNumChars.

 	The text line that is to be justified has a certain number of characters

 	this includes the spaces between the words. It also has a distance (in 

 	pixels) between the end of the last word and the actual end of the line 

 	(right hand margin, usually). These excess width pixels are distributed 

 	amongst all the characters, increasing the gaps between them, to achieve 

 	full justification of the text line.

 	Use CFont::TextCount() to return the excess width.

 	Notes:

 	This function is provided to allow simulation of printer fonts on screen. 

 	Due to the fact that fully-scalable fonts are not used before v5, large 

 	printer fonts can be simulated by using the nearest smaller font and 

 	widening it slightly.

 	If the excess width is zero, then calling SetCharJustification() has no 

 	effect.

 	SetCharJustification() is required for WYSIWYG where the layout uses 

 	printer font metrics but screen fonts have to be drawn on the screen. 

 	Because continuously scalable typefaces (c.f. TrueType) are not used 

 	before v5 and because screen fonts are coarser and less numerous in 

 	their variety than the printer fonts, the best matching smaller screen 

 	font must be used with character justification to simulate the printer 

 	font on the screen.

 	There is also a situation where the gaps between characters on screen have 

 	to be reduced with character clipping. The screen font that best matches 

 	the printer font may have the required height, but has characters that are 

 	too wide. A line of text that works on the printer will then be too long 

 	on the screen, unless it is squashed horizontally. The number of pixels 

 	that overlap the end of the screen line must now be removed from the gaps 

 	between the characters, i.e. there is a negative excess width. This 

 	situation is especially important where adding a TAB on screen gives 

 	perfectly acceptable printout, but would push the last character of the 

 	line off the right hand side of the screen.

 	In practice what you do in printer layout mode is:

 	Calculate where the line breaks will come on the printer. To do this you 

 	use a printer font (which in practice means a table of character widths 

 	of the font that the printer will use).

 	Now change to use a screen font that is the closest font which is no taller 

 	that the printer font. In practice it will often be fatter maybe only for 

 	certain characters such as 'i'.

 	You have to recalculate the width of the characters using the screen fonts. 

 	You can do this using CFont::TextWidth() as you have already determined how 

 	many characters will fit on the line.

 	If, in the screen font, the characters are not as wide as the line then you 

 	can just use word justification to expand the line. You would only do this 

 	if the text is to be justified.

 	If, however, the characters are wider than the line then you would use 

 	character justification to clip each character. You would need to do this 

 	even if the line is not justified.

 	Thus, in practice, character justification will only very rarely be used to 

 	expand a line of characters.

 	@param aExcessWidth The excess width (in pixels) to be distributed between 

 	the specified number of characters. It may be positive, in which case the text is 

 	stretched, or negative, in which case it is shrunk.

 	@param aNumChars The number of characters involved. */

 	virtual void SetCharJustification(TInt aExcessWidth,TInt aNumChars)=0;

 	/** Sets the pen colour.

 	The effective pen colour depends on the drawing mode. The default pen colour 

 	is black.

 	Note:

 	The pen is used to draw lines, the outlines of filled shapes, and text. In case

 	of outlined text, the pen is used to draw the outline of the font.

 	The	class provides member functions to set the colour of the pen, the style of 

 	line and the line size drawn.

 	@param aColor An RGB colour for the pen. 

 	@see CGraphicsContext::SetDrawMode() */

 	virtual void SetPenColor(const TRgb& aColor)=0;

 	/** Sets the line drawing style for the pen. 

 	There are 6 pen styles. If no pen style is set, then the default is 

 	TPenStyle::ESolidPen. To use a pen style, its full context must be given, 

 	e.g. for a null pen:

 	CGraphicsContext::TPenStyle::ENullPen

 	Notes:

 	The pen is used to draw lines, the outlines of filled shapes, and text. 

 	CGraphicsContext member functions are provided to set the colour of the 

 	pen, the style of line and the line size drawn.

 	The TPenStyle::ENullPen style should be used if a border is not required 

 	around a filled shape.

 	Dotted and dashed pen styles have a device dependant implementation, always 

 	give single-pixel size lines on the screen whatever the pen size set 

 	by SetPenSize() and can only be used for straight lines, polylines, 

 	non-rounded rectangles and polygons.

 	The dotted/dashed pattern is continued, without re-starting, for all 

 	consecutively drawn straight lines, i.e.

 	the outlines of rectangles the pattern starts in the top left corner. 

 	It is reset at the end of the function call.

 	the outlines of polygons the pattern starts at the first point. It is 

 	reset at the end of the function call.

 	polylines and straight lines the pattern starts at the first point 

 	initially. Consecutive calls to DrawLine() and/or DrawPolyLine(), whether 

 	the lines are concatenated or not, continue the pattern. It can be reset 

 	by a further call to SetPenStyle() using the same dotted/dashed style 

 	parameter.

 	@param aPenStyle A pen style. 

 	@see CGraphicsContext::TPenStyle */

 	virtual void SetPenStyle(TPenStyle aPenStyle)=0;

 	/** Sets the line drawing size for the pen.

 	Lines of size greater than one pixel:

 	are drawn with rounded ends that extend beyond the end points, (as if the 

 	line is drawn using a circular pen tip of the specified size).

 	are always drawn in TDrawMode::EDrawModePEN mode, overriding whatever mode 

 	has been set using SetDrawMode().

 	Notes:

 	The pen is used to draw lines, the outlines of filled shapes, and text. The 

 	class provides member functions to set the colour of the pen, the style of 

 	line and the line size drawn.

 	Wide straight lines and arcs have rounded ends so that concatenated wide 

 	lines have smoothly rounded corners at the vertexes.

 	When lines are made wide, the extra strips of pixels are added equally to 

 	both sides of the line. This works precisely for lines of odd pixel size 

 	(3, 5, 7, etc.). Wide lines of even pixel size, (2, 4, 6, etc.), 

 	have the extra strip of pixels added to the right and/or below the line.

 	Wide outlines of ellipses and wide line arcs are drawn with the pixels 

 	distributed either side of a thin (single pixel wide) true ellipse 

 	constructed in the normal manner. Wide ellipses and arcs of even pixel 

 	size have the extra strip of pixels added to the right and/or below the 

 	curved line. This gives a slight asymmetry to ellipses.

 	If the pen style is dotted or dashed, the size specification is ignored: a 

 	single-pixel wide primitive is drawn, (this is device dependant).

 	A line size of zero is handled as if the pen style had been set to 

 	TPenStyle::ENullPen.

 	@param aSize A line size. The default is 1 pixel. */

 	virtual void SetPenSize(const TSize& aSize)=0;

 	/** Sets the brush colour.

 	The effective brush colour depends on the drawing mode.

 	Notes:

 	The brush is used for filling shapes and the background of text boxes. In 

 	case of outlined text, the brush is used for filling the font. The brush 

 	has colour, style, pattern and pattern origin parameters.

 	If no brush colour has been set, it defaults to white. However the default 

 	brush style is null, so when drawing to a window the default appears to be 

 	the window's background colour.

 	@param aColor An RGB colour for the brush. 

 	@see SetDrawMode() */

 	virtual void SetBrushColor(const TRgb& aColor)=0;

 	/**	Sets the brush style.

 	Ten brush styles are provided, including six built-in hatching patterns.

 	Note: The brush is used for filling shapes and the background of text boxes.

 	The brush has colour, style, pattern and pattern origin parameters.

 	Note: Use TBrushStyle::ENullBrush to draw the outline of a fillable

 	shape on its own, without filling.

 	Note: If the TBrushStyle::EPatternedBrush style is set, but no bitmap 

 	pattern has been selected using UseBrushPattern(), then the function panics.

 	Note: Hatching lines are done in the current pen colour, set using SetPenColor(). 

 	The hatching pattern starts at the brush origin, set using SetBrushOrigin().

 	@see TBrushStyle::ENullBrush

 	@see TBrushStyle::EPatternedBrush

 	@see UseBrushPattern()

 	@see SetPenColor()

 	@see SetBrushOrigin()

 	@publishedAll

 	@released

 	@param aBrushStyle A brush style. */

 	virtual void SetBrushStyle(TBrushStyle aBrushStyle)=0;

 	/** Sets the brush pattern origin.

 	This specifies the top left-hand corner position for the pattern tile around 

 	which copies of the pattern are tiled.

 	The brush pattern may be a built-in style, or a bitmap. To use a bitmap, the 

 	brush must have a pattern set and the brush style must be set to 

 	TBrushStyle::EPatternedBrush.

 	Notes

 	The brush is used for filling shapes and the background of text boxes. The 

 	brush has colour, style, pattern and pattern origin parameters.

 	If SetBrushOrigin() is not used, then the origin defaults to (0,0).

 	This brush origin remains in effect for all fillable shapes drawn 

 	subsequently, until a new brush origin is set. Shapes can thus be 

 	considered as windows onto a continuous pattern field (covering the whole 

 	clipping region of a screen device, or the whole device area of a printer).

 	@param aOrigin An origin point for the brush. The coordinates are relative 

 	to the rectangle to fill, i.e. specify 0,0 to align the pattern flush with 

 	the top and left hand sides of the rectangle.

 	@see SetBrushStyle()

 	@see UseBrushPattern() */

 	virtual void SetBrushOrigin(const TPoint& aOrigin)=0;

 	/** Sets the brush pattern to the specified bitmap.

 	For the brush to actually use the bitmap, TBrushStyle::EPatternedBrush must 

 	be used to set the brush style.

 	When the brush pattern is no longer required, use DiscardBrushPattern() to 

 	free up the memory used, if the bitmap is not being shared. 

 	If UseBrushPattern() is used again without using DiscardBrushPattern() 

 	then the previous pattern is discarded automatically.

 	Notes:

 	The brush is used for filling shapes and the background of text boxes. The 

 	brush has colour, style, pattern and pattern origin parameters.

 	When loading a bitmap, the bitmap is checked to see if it is already in 

 	memory. If the bitmap is already there, then that copy is shared.

 	The brush does not need to have a pattern set at all. There are several 

 	built-in hatching patterns which can be selected using SetBrushStyle().

 	@param aBitmap A bitmap pattern for the brush. 

 	@see SetBrushStyle() */

 	virtual void UseBrushPattern(const CFbsBitmap* aBitmap)=0;

 	/** Discards a non-built-in brush pattern.

 	This frees up the memory used by the bitmap, if it is not being shared by 

 	another process.

 	Notes:

 	The brush is used for filling shapes and the background of text boxes. The 

 	brush has colour, style, pattern and pattern origin parameters.

 	If DiscardBrushPattern() is used, with no brush pattern set, then there is 

 	no effect. */

 	virtual void DiscardBrushPattern()=0;

 	/** Sets the drawing point relative to the co-ordinate origin. 

 	A subsequent call to DrawLineTo() or DrawLineBy() uses the new drawing 

 	point as the start point for the line drawn.

 	Notes

 	The operations DrawLine(), DrawLineTo(), DrawLineBy() and DrawPolyline() 

 	also change the internal drawing position to the last point of the drawn 

 	line(s). 

 	The internal drawing position is set to the co-ordinate origin if no drawing 

 	or moving operations have yet taken place.

 	@param aPoint The new internal drawing position. */

 	virtual void MoveTo(const TPoint& aPoint)=0;

 	/** Sets the drawing point relative to the current co-ordinates.

 	A subsequent call to DrawLineTo() or DrawLineBy() uses the new drawing point 

 	as the start point for the line drawn.

 	Notes

 	The operations DrawLine(), DrawLineTo(), DrawLineBy() and DrawPolyline() 

 	also change the internal drawing position to the last point of the drawn 

 	line(s). 

 	The internal drawing position is set to the co-ordinate origin if no drawing 

 	or moving operations have yet taken place.

 	@param aVector The amount by which the internal drawing position is to move. */

 	virtual void MoveBy(const TPoint& aVector)=0;

 	/** Draws a single point. The point is drawn with the current pen settings 

 	using the current drawing mode.

 	Note:

 	If the pen size is greater than one pixel, a filled circle of the current 

 	pen colour is drawn, with the pen size as the diameter and the plotted point 

 	as the centre. If the pen size is an even number of pixels, the extra pixels 

 	are drawn below and to the right of the centre.

 	@param aPoint The point to be drawn.

 	@see SetPenSize() */

 	virtual void Plot(const TPoint& aPoint)=0;

 	/** Draws an arc.

 	The arc is considered a portion of an ellipse. The ellipse is defined by the 

 	TRect argument.

 	The pixels at both the start point and the end point are drawn.

 	The arc itself is the segment of the ellipse drawn in an anti-clockwise 

 	direction from the start point to the end point.

 	Notes:

 	A rectangle is used in the construction of the ellipse of which the arc is 

 	a segment. This rectangle is passed as an argument of type TRect.

 	A wide line arc is drawn with the pixels distributed either side of a true 

 	ellipse, in such a way that the outer edge of the line would touch the edge 

 	of the construction rectangle. In other words, the ellipse used to 

 	construct it is slightly smaller than that for a single pixel line size.

 	If the specified start or end point is at the centre of the ellipse, then 

 	the line that defines the start or end of the arc defaults to one extending 

 	vertically above the centre point.

 	If the start and end point are the same point or are points on the same line 

 	through the ellipse centre then a complete unfilled ellipse is drawn.

 	@param aRect A rectangle in which to draw the ellipse, of which the arc is 

 	a segment. 

 	@param aStart The point defining the start of the arc. It defines one end of 

 	a line from the geometric centre of the ellipse. The point of intersection 

 	between this line and the ellipse defines the start point of the arc.

 	@param aEnd The point defining the end of the arc. It defines one end of a 

 	second line from the geometric centre of the ellipse. The point of 

 	intersection between this line and the ellipse defines the end point of the 

 	arc.

 	@see DrawEllipse() */

 	virtual void DrawArc(const TRect& aRect,const TPoint& aStart,const TPoint& aEnd)=0;

 	/** Draws a straight line between two points.

 	@param aPoint1 The point at the start of the line. 

 	@param aPoint2 The point at the end of the line. */

 	virtual void DrawLine(const TPoint& aPoint1,const TPoint& aPoint2)=0;

 	/** Draws a straight line from the current drawing point to a specified 

 	point.

 	@param aPoint The point at the end of the line. 

 	@see MoveTo()

 	@see MoveBy() */

 	virtual void DrawLineTo(const TPoint& aPoint)=0;

 	/** Draws a straight line relative to the current drawing point, using a 

 	vector.

 	The start point of the line is the current drawing point. The specified 

 	vector 

 	is added to the drawing point to give the end point of the line

 	@param aVector The vector to add to the current internal drawing position, 

 	giving the end point of the line. 

 	@see MoveTo()

 	@see MoveBy() */

 	virtual void DrawLineBy(const TPoint& aVector)=0;

 	/** Draws a polyline from a set of points in an array.

 	A polyline is a series of concatenated straight lines joining a set of 

 	points.

 	@param aPointList An array containing the points on the polyline. */

 	virtual void DrawPolyLine(const CArrayFix<TPoint>* aPointList)=0;

 	/** Draws a polyline from a set of points in a list.

 	A polyline is a series of concatenated straight lines joining a set of 

 	points.

 	@param aPointList Pointer to a set of points on the polyline.

 	@param aNumPoints Number of points in the list. */

 	virtual void DrawPolyLine(const TPoint* aPointList,TInt aNumPoints)=0;

 	/** Draws and fills a pie slice.

 	The pie slice is an area bounded by:

 	the arc of an ellipse drawn in an anticlockwise direction from the start 

 	point to the end point

 	the straight line drawn to the start point from the geometric centre of the 

 	ellipse.

 	the straight line to the end point from the geometric centre of the ellipse.

 	Notes:

 	A rectangle is used in the construction of the pie slice. This rectangle is 

 	passed as an argument of type TRect. The curved edge of the pie slice is an 

 	arc of an ellipse constructed within the rectangle.

 	The line drawn by the pen goes inside the specified rectangle.

 	The pixels at the end point of the arc are not drawn.

 	A wide line edged pie slice has the arc drawn with the pixels distributed 

 	either side of a true ellipse. This is done in such a way that the outer 

 	edge of the line touches the edge of the construction rectangle. In other 

 	words, the ellipse used to construct it is slightly smaller than that for 

 	a single pixel line size.

 	If the specified start or end point is at the centre of the ellipse, then 

 	the line that defines the start or end of the arc defaults to one extending 

 	vertically above the centre point.

 	If the start and end point are the same point or are points on the same line 

 	through the ellipse centre then a complete filled ellipse is drawn. A line 

 	is also drawn from the edge to the ellipse centre.

 	@param aRect A rectangle in which to draw the ellipse bounding the pie slice. 

 	@param aStart A point defining the start of the arc bounding the pie slice. 

 	It defines one end of a line from the geometrical centre of the ellipse. The 

 	point of intersection between this line and the ellipse defines the start 

 	point of the arc.

 	@param aEnd A point to define the end of the arc bounding the pie slice. It 

 	defines one end of a second line from the geometrical centre of the ellipse. 

 	The point of intersection between this line and the ellipse defines the end 

 	point of the arc. */

 	virtual void DrawPie(const TRect& aRect,const TPoint& aStart,const TPoint& aEnd)=0;

 	/** Draws and fills an ellipse.

 	The ellipse is drawn inside the rectangle defined by the TRect argument. Any 

 	rectangle that has odd pixel dimensions, has the bottom right corner trimmed 

 	to give even pixel dimensions before the ellipse is constructed.

 	Note:

 	A wide outline ellipse is drawn with the pixels distributed either side of