CFbsBitmapDevice in Graphics BITGDI

class CFbsBitmapDevice : public CFbsDevice;

Description

A graphics device to which a bitmap managed by the font and bitmap server can be drawn.

The class specialises the bitmap graphics device interface CBitmapDevice for drawing to in-memory bitmaps.

Derivation

MGraphicsDeviceMap - Interface class for mapping between twips and device-specific units (pixels)
CBase - Base class for all classes to be instantiated on the heap

CGraphicsDevice - Specifies the interface for concrete device classes

CBitmapDevice - Defines an abstract interface for the capabilities and attributes of a bitmapped graphics device

CFbsDevice - Abstract base class for graphics devices to which bitmaps and fonts can be drawn

CFbsBitmapDevice - A graphics device to which a bitmap managed by the font and bitmap server can be drawn

Members

Defined in CFbsBitmapDevice:
DrawingBegin(), DrawingEnd(), GetPalette(), GetPixel(), GetScanLine(), HorizontalPixelsToTwips(), HorizontalTwipsToPixels(), NewL(), NewL(), PaletteAttributes(), Resize(), SetBits(), SetPalette(), SizeInTwips(), SwapWidthAndHeight(), VerticalPixelsToTwips(), VerticalTwipsToPixels(), ~CFbsBitmapDevice()

Inherited from CBase:
Delete(), Extension_(), operator new()

Inherited from CBitmapDevice:
CreateBitmapContext()

Inherited from CFbsDevice:
AddFile(), CancelSprite(), CreateContext(), DisplayMode(), DisplayMode16M(), FontHeightInPixels(), FontHeightInTwips(), GetDrawRect(), GetFontById(), GetNearestFontInPixels(), GetNearestFontInTwips(), GetNearestFontToDesignHeightInPixels(), GetNearestFontToDesignHeightInTwips(), GetNearestFontToMaxHeightInPixels(), GetNearestFontToMaxHeightInTwips(), GraphicsAccelerator(), HideSprite(), NumTypefaces(), Orientation(), RectCompare(), ReleaseFont(), RemoveFile(), SetCustomPalette(), SetScalingFactor(), ShowSprite(), SizeInPixels(), TypefaceSupport(), iBitBltMaskedBuffer, iDrawDevice, iFbs, iGraphicsAccelerator, iOrientation, iScreenDevice, iSpare, iTypefaceStore

Inherited from MGraphicsDeviceMap:
PixelsToTwips(), TwipsToPixels()

static IMPORT_C CFbsBitmapDevice *NewL(CFbsBitmap *aFbsBitmap);

Description

Allocates and constructs the device with the bitmap. Also creates a 2D graphics accelerator which is owned and used by the device.

Parameters


                              CFbsBitmap *aFbsBitmap

A pointer to the font and bitmap server managed bitmap.

Return value

CFbsBitmapDevice *

A pointer to the newly constructed device.

Leave codes

`KErrArgument`	The bitmap's handle is zero.
`KErrAccessDenied`	The bitmap is in the ROM.

Panic codes

EBitgdiPanicInvalidBitmap

aFbsBitmap is NULL.

static IMPORT_C CFbsBitmapDevice *NewL(CFbsBitmap *aFbsBitmap, const TDesC &aLibname);

Description

Constructs the object from the specified Font and Bitmap server managed bitmap.

Parameters

`CFbsBitmap *aFbsBitmap`	A pointer to a Font and Bitmap server managed bitmap.
`const TDesC &aLibname`	Name of the library to create the low-level `CFbsDrawDevice` object from.

Return value

CFbsBitmapDevice *

A pointer to the newly constructed graphics device.

virtual IMPORT_C ~CFbsBitmapDevice();

Description

Frees all resources owned by the object prior to its destruction.

IMPORT_C TInt Resize(const TSize &aSize);

Description

Resizes the device.

Parameters

const TSize &aSize

The new size in pixels.

Return value

TInt

KErrNone, if successful; otherwise another of the system-wide error codes.

virtual IMPORT_C void GetScanLine(TDes8 &aBuf, const TPoint &aStartPixel, TInt aLength, TDisplayMode iDispMode) const;

Description

Copies a scanline into a buffer.

The function provides a concrete implementation of the pure virtual function CBitmapDevice::GetScanLine().

Parameters

`TDes8 &aBuf`
`const TPoint &aStartPixel`
`TInt aLength`
`TDisplayMode iDispMode`

virtual IMPORT_C void GetPixel(TRgb &aColor, const TPoint &aPixel) const;

Description

Gets the RGB colour of an individual pixel on a bitmapped graphics device.

The function provides a concrete implementation of the pure virtual function CBitmapDevice::GetPixel().

Parameters

`TRgb &aColor`
`const TPoint &aPixel`

virtual IMPORT_C TInt HorizontalPixelsToTwips(TInt aPixels) const;

Description

Converts a horizontal dimension of a device in pixels to a horizontal dimension in twips.

The function provides a concrete implementation of the pure virtual function MGraphicsDeviceMap::HorizontalPixelsToTwips().

Parameters


                              TInt aPixels

Return value

TInt

virtual IMPORT_C TInt VerticalPixelsToTwips(TInt aPixels) const;

Description

Converts a vertical dimension of a device in pixels to a vertical dimension in twips.

The function provides a concrete implementation of the pure virtual function MGraphicsDeviceMap::VerticalPixelsToTwips().

Parameters


                              TInt aPixels

Return value

TInt

virtual IMPORT_C TInt HorizontalTwipsToPixels(TInt aTwips) const;

Description

Converts a horizontal dimension of a device in twips to a horizontal dimension in pixels.

The function provides a concrete implementation of the pure virtual function MGraphicsDeviceMap::HorizontalTwipsToPixels().

Parameters


                              TInt aTwips

Return value

TInt

virtual IMPORT_C TInt VerticalTwipsToPixels(TInt aTwips) const;

Description

Converts a vertical dimension of a device in twips to a vertical dimension in pixels.

The function provides a concrete implementation of the pure virtual function MGraphicsDeviceMap::VerticalTwipsToPixels().

Parameters


                              TInt aTwips

Return value

TInt

virtual IMPORT_C TSize SizeInTwips() const;

Description

Gets the size of the device, in twips.

Return value

TSize

The size of the device.

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

Description

Gets the palette attributes of the device.

The function provides a concrete implementation of the pure virtual function CGraphicsDevice::PaletteAttributes().

Parameters

`TBool &aModifiable`
`TInt &aNumEntries`

virtual IMPORT_C void SetPalette(CPalette *aPalette);

Description

Sets the device's palette to the specified palette.

The function provides a concrete implementation of the pure virtual function CGraphicsDevice::SetPalette().

Parameters


                              CPalette *aPalette

virtual IMPORT_C TInt GetPalette(CPalette *&aPalette) const;

Description

Gets the device's current palette.

The function provides a concrete implementation of the pure virtual function CGraphicsDevice::GetPalette().

Parameters


                              CPalette *&aPalette

Return value

TInt

virtual IMPORT_C void DrawingBegin(TBool aAlways=EFalse);

Description

This method is called when you are about to start direct drawing to the bitmap memory. Calls to DrawingBegin() must be paired with a subsequent call to DrawingEnd(). Also, code must not leave between a DrawingBegin() - DrawingEnd() pair.

Parameters


                              TBool aAlways

Not used.

Description

This method is called when you have finished direct drawing to the bitmap memory. Calls to DrawingEnd() must correspond to a prior call to DrawingBegin().

Parameters


                              TBool aAlways

Not used.

Description

The method swaps bitmap device's width and height. For example: if the size is (40, 20), the swapped size will be (20, 40). The device's content is not preserved. The method leaves CFbsBitmapDevice object in a consistent state - scaling settings will be set with their default values (the scaling is switched off), the device's dither origin will be set to (0,0), scaling origin to (0,0).

Note: If the device was scaled or its dither origin was set with a non-default value, it has to be rescaled again, respectivelly the dither origin has to be set again.

Note: All graphics contexts, already created by the device, should be re-activated calling CFbsBitGc::Activate().

Note: Do not call SwapWidthAndHeight() between DrawingBegin() and DrawingEnd() calls!

Return value

TInt

KErrNone The call was successfull. KErrAccessDenied ROM bitmap size can't be swapped. KErrNotSupported Hardware bitmap size can't be swapped. KErrGeneral iDrawDevice or iFbsBmp is NULL.

private: virtual void SetBits();

Description

Sets the bit level.

Class CFbsBitmapDevice

Description

Derivation

Members

Construction and destruction

NewL()

Description

Parameters

Return value

Leave codes

Panic codes

NewL()

Description

Parameters

Return value