Class CFbsDevice

class CFbsDevice : public CBitmapDevice;

Description

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

The class implements the pure virtual CBitmapDevice functions and additionally provides:

support for creating and enquiring about fonts

comparing two device rectangles

creating a graphics context for the device.

CFbsBitmapDevice and CFbsScreenDevice are derived fom this class.

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...

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

Members

Defined in CFbsDevice:

• AddFile(const TDesC &,TInt &)Adds a font file to the device's typeface store. The specified font file must be...
• CancelSprite()constCancels drawing the sprite.
• CreateContext(CFbsBitGc *&)Creates a font and bitmap server graphics context for the device and activates i...
• CreateContext(CGraphicsContext *&)Creates a font and bitmap server graphics context for the device and activates i...
• DisplayMode()constGets the device's display mode.
• DisplayMode16M()Depending on the current graphics hardware this will return one of the 16M video...
• DrawingBegin(TBool)
• DrawingEnd(TBool)
• FontHeightInPixels(TInt,TInt)constGets the height, in pixels, of the specified typeface at one of its defined heig...
• FontHeightInTwips(TInt,TInt)constGets the height of a font in twips.
• GetDrawRect(TRect &)constGets logical coordinates of the drawing rectangle. If the device is not scaled, ...
• GetFontById(CFbsFont *&,TUid,const TAlgStyle &)Gets a specific bitmap font, identified by its UID, from the device's typeface s...
• GetFontById(CFont *&,TUid,const TAlgStyle &)Gets a specific bitmap font, identified by its UID, from the device's typeface s...
• GetNearestFontInPixels(CFbsFont *&,const TFontSpec &)Creates a client-side FBSERV font from those available in the device's typeface ...
• GetNearestFontInPixels(CFont *&,const TFontSpec &)Creates a client-side font from those available in the device's typeface store t...
• GetNearestFontInTwips(CFbsFont *&,const TFontSpec &)Creates a client-side FBSERV font from those available in the device's typeface ...
• GetNearestFontInTwips(CFont *&,const TFontSpec &)Provides access to a client-side font object in the device's typeface store that...
• GetNearestFontToDesignHeightInPixels(CFbsFont *&,const TFontSpec &)Creates a client-side FBSERV font from those available in the device's typeface ...
• GetNearestFontToDesignHeightInPixels(CFont *&,const TFontSpec &)Creates a client-side font from those available in the device's typeface store t...
• GetNearestFontToDesignHeightInTwips(CFbsFont *&,const TFontSpec &)Creates a client-side FBSERV font from those available in the device's typeface ...
• GetNearestFontToDesignHeightInTwips(CFont *&,const TFontSpec &)Creates a client-side font from those available in the device's typeface store t...
• GetNearestFontToMaxHeightInPixels(CFbsFont *&,const TFontSpec &,TInt)Creates a client-side FBSERV font from those available in the device's typeface ...
• GetNearestFontToMaxHeightInPixels(CFont *&,const TFontSpec &,TInt)Creates a client-side font from those available in the device's typeface store t...
• GetNearestFontToMaxHeightInTwips(CFbsFont *&,const TFontSpec &,TInt)Creates a client-side FBSERV font from those available in the device's typeface ...
• GetNearestFontToMaxHeightInTwips(CFont *&,const TFontSpec &,TInt)Creates a client-side font from those available in the device's typeface store t...
• GraphicsAccelerator()constGets a pointer to the 2D graphics accelerator owned by the device. If one is ava...
• HideSprite()constHides the sprite over the whole screen.
• HideSprite(const TRect &,const TRegion *)constHides the sprite within a particular region.
• NumTypefaces()constGets the number of typefaces supported by the device.
• Orientation()constGets the device's orientation. The orientation can be set using CFbsBitGc::SetOr...
• RectCompare(const TRect &,const CFbsDevice &,const TRect &)constCompares two rectangles, including their contents.
• ReleaseFont(CFont *)Marks the specified font as no longer needed by the user of the device.
• RemoveFile(TInt)Removes the specified font file from the device's typeface store. If the default...
• SetBits()Sets the bit level.
• SetCustomPalette(const CPalette *)Sets the variable 8 bits per pixel colour palette, replacing the system default ...
• SetScalingFactor(const TPoint &,TInt,TInt,TInt,TInt)Sets scaling factor by which the drawing device should scale the drawing images....
• ShowSprite(TSpriteBase *)constShows the specified sprite over the whole screen.
• ShowSprite(TSpriteBase *,const TRect &,const TRegion *)constShows the specified sprite within a particular region.
• SizeInPixels()constGets the size of the device, in pixels.
• TypefaceSupport(TTypefaceSupport &,TInt)constGets information about an indexed typeface.
• iBitBltMaskedBuffer
• iDrawDevice
• iFbs
• iGraphicsAccelerator
• iOrientation
• iScreenDevice
• iSpare
• iTypefaceStore
• ~CFbsDevice()Frees all resources owned by the object prior to its destruction.

Inherited from CBase:

• Delete(CBase *)Deletes the specified object.
• Extension_(TUint,TAny *&,TAny *)Extension function
• operator new(TUint)Allocates the object from the heap and then initialises its contents to binary z...
• operator new(TUint,TAny *)Initialises the object to binary zeroes.
• operator new(TUint,TLeave)Allocates the object from the heap and then initialises its contents to binary z...
• operator new(TUint,TLeave,TUint)Allocates the object from the heap and then initialises its contents to binary z...
• operator new(TUint,TUint)Allocates the object from the heap and then initialises its contents to binary z...

Inherited from CBitmapDevice:

• CreateBitmapContext(CBitmapContext *&)Creates a bitmap context for this bitmap device.
• GetPixel(TRgb &,const TPoint &)constGets the RGB colour of an individual pixel on a bitmapped graphics device.
• GetScanLine(TDes8 &,const TPoint &,TInt,TDisplayMode)constCopies a scanline into a buffer.

Inherited from CGraphicsDevice:

• GetPalette(CPalette *&)constGets the device's current palette.
• PaletteAttributes(TBool &,TInt &)constGets the palette attributes of the device.
• SetPalette(CPalette *)Sets the device's palette.
• SizeInTwips()constGets the size of the device area in twips.

Inherited from MGraphicsDeviceMap:

• HorizontalPixelsToTwips(TInt)constConverts a horizontal dimension from pixels to twips.
• HorizontalTwipsToPixels(TInt)constConverts a horizontal dimension from twips to pixels.
• PixelsToTwips(const TPoint &)constConverts a point in pixels to a point in twips.
• PixelsToTwips(const TRect &)constConverts a rectangle in pixels to a rectangle in twips.
• TwipsToPixels(const TPoint &)constConverts a point in twips to a point in pixels.
• TwipsToPixels(const TRect &)constConverts a rectangle in twips to a rectangle in pixels.
• VerticalPixelsToTwips(TInt)constConverts a vertical dimension from pixels to twips.
• VerticalTwipsToPixels(TInt)constConverts a vertical dimension from twips to pixels.

See also:

• CFbsBitmapDeviceA graphics device to which a bitmap managed by the font and bitmap server can be...
• CFbsScreenDeviceA graphics device interface that provides direct access to the screen, without t...

IMPORT_C ~CFbsDevice();

Description

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

IMPORT_C TInt CreateContext(CFbsBitGc *&aGc);

Description

Creates a font and bitmap server graphics context for the device and activates it.

It is the responsibility of the caller to delete the graphics context when it is no longer needed.

Parameters

Return value

virtual inline TInt CreateContext(CGraphicsContext *&aGc);

Description

Creates a font and bitmap server graphics context for the device and activates it.

It is the responsibility of the caller to delete the graphics context when it is no longer needed.

Parameters

Return value

IMPORT_C virtual TDisplayMode DisplayMode() const;

Description

Gets the device's display mode.

Return value

IMPORT_C virtual TSize SizeInPixels() const;

Description

Gets the size of the device, in pixels.

Return value

IMPORT_C TBool RectCompare(const TRect &aSourceRect, const CFbsDevice &aDevice, const TRect &aDeviceRect) const;

Description

Compares two rectangles, including their contents.

This function is intended for use by test code only.

Parameters

Return value

IMPORT_C virtual TInt AddFile(const TDesC &aName, TInt &aId);

Description

Adds a font file to the device's typeface store. The specified font file must be accessible to any process, i.e. not located inside an application's private directory.

Parameters

Return value

IMPORT_C virtual void RemoveFile(TInt aId=0);

Description

Removes the specified font file from the device's typeface store. If the default value of zero is used, this deletes all font files.

Parameters

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

Description

Provides access to a client-side font object in the device's typeface store that most closely matches a font specification.

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

Note that this deprecated function is replaced by the new GetNearestFontToDesignHeightInTwips() yielding (virtually) the same result. However clients are strongly encouraged to use the new 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.

Parameters

Return value

IMPORT_C virtual TInt GetNearestFontInPixels(CFont *&aFont, const TFontSpec &aFontSpec);

Description

Creates a client-side font from those available in the device's typeface store that most closely matches a font specification.

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

Note that this deprecated function is replaced by the new GetNearestFontToDesignHeightInPixels() yielding (virtually) the same result. However clients are strongly encouraged to use the new GetNearestFontToMaxHeightInPixels() function instead. This will guarantee that every character within any given text string will fit within the given amount of pixels, whereas the design height is an aesthetic unit decided by the font designer without strict physical meaning, which may result in cropped characters.

Parameters

Return value

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

Description

Creates a client-side font from those available in the device's typeface store that most closely matches a font specification.

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

This new function replaces the deprecated GetNearestFontInTwips() yielding (virtually) the same result. However clients are strongly encouraged to use the new 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.

Parameters

Return value

IMPORT_C virtual TInt GetNearestFontToDesignHeightInPixels(CFont *&aFont, const TFontSpec &aFontSpec);

Description

Creates a client-side font from those available in the device's typeface store that most closely matches a font specification.

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

This new function replaces the deprecated GetNearestFontInPixels() yielding (virtually) the same result. However clients are strongly encouraged to use the new GetNearestFontToMaxHeightInPixels() function instead. This will guarantee that every character within any given text string will fit within the given amount of pixels, whereas the design height is an aesthetic unit decided by the font designer without strict physical meaning, which may result in cropped characters.

Parameters

Return value

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

Description

Creates a client-side font from those available in the device's typeface store that most closely matches a font specification.

When the font is no longer needed, call 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.

Parameters

Return value

IMPORT_C virtual TInt GetNearestFontToMaxHeightInPixels(CFont *&aFont, const TFontSpec &aFontSpec, TInt aMaxHeight);

Description

Creates a client-side font from those available in the device's typeface store that most closely matches a font specification.

When the font is no longer needed, call 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.

Parameters

Return value

IMPORT_C TInt GetFontById(CFont *&aFont, TUid aFileId, const TAlgStyle &aStyle);

Description

Gets a specific bitmap font, identified by its UID, from the device's typeface store.

When the font is no longer needed, call CFbsDevice::ReleaseFont(CFont *).

Parameters

Return value

inline TInt GetNearestFontInTwips(CFbsFont *&aFont, const TFontSpec &aFontSpec);

Description

Creates a client-side FBSERV font from those available in the device's typeface store that most closely matches a font specification.

When the font is no longer needed, call CFbsDevice::ReleaseFont(CFont *).

This function is replaced by CFbsDevice::GetNearestFontToDesignHeightInTwips(CFont *&,const TFontSpec &).

Parameters

Return value

inline TInt GetNearestFontInPixels(CFbsFont *&aFont, const TFontSpec &aFontSpec);

Description

Creates a client-side FBSERV font from those available in the device's typeface store that most closely matches a font specification.

When the font is no longer needed, call CFbsDevice::ReleaseFont(CFont *).

This function is replaced by CFbsDevice::GetNearestFontToDesignHeightInPixels(CFont *&,const TFontSpec &).

Parameters

Return value

inline TInt GetNearestFontToDesignHeightInTwips(CFbsFont *&aFont, const TFontSpec &aFontSpec);

Description

Creates a client-side FBSERV font from those available in the device's typeface store that most closely matches a font specification.

When the font is no longer needed, call CFbsDevice::ReleaseFont(CFont *).

This function replaces CFbsDevice::GetNearestFontInTwips(CFont *&,const TFontSpec &).

Parameters

Return value

inline TInt GetNearestFontToDesignHeightInPixels(CFbsFont *&aFont, const TFontSpec &aFontSpec);

Description

Creates a client-side FBSERV font from those available in the device's typeface store that most closely matches a font specification.

When the font is no longer needed, call CFbsDevice::ReleaseFont(CFont *).

This function replaces CFbsDevice::GetNearestFontInPixels(CFont *&,const TFontSpec &).

Parameters

Return value

inline TInt GetNearestFontToMaxHeightInTwips(CFbsFont *&aFont, const TFontSpec &aFontSpec, TInt aMaxHeight);

Description

Creates a client-side FBSERV font from those available in the device's typeface store that most closely matches a font specification.

When the font is no longer needed, call CFbsDevice::ReleaseFont(CFont *).

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.

Parameters

Return value

inline TInt GetNearestFontToMaxHeightInPixels(CFbsFont *&aFont, const TFontSpec &aFontSpec, TInt aMaxHeight);

Description

Creates a client-side FBSERV font from those available in the device's typeface store that most closely matches a font specification.

When the font is no longer needed, call CFbsDevice::ReleaseFont(CFont *).

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.

Parameters

Return value

inline TInt GetFontById(CFbsFont *&aFont, TUid aFileId, const TAlgStyle &aStyle);

Description

Gets a specific bitmap font, identified by its UID, from the device's typeface store.

When the font is no longer needed, call CFbsDevice::ReleaseFont(CFont *).

Parameters

Return value

IMPORT_C virtual void ReleaseFont(CFont *aFont);

Description

Marks the specified font as no longer needed by the user of the device.

As fonts can be shared between applications, this function does not delete the copy of the font from RAM unless the font is only being used by this device.

Parameters

IMPORT_C virtual TInt FontHeightInTwips(TInt aTypefaceIndex, TInt aHeightIndex) const;

Description

Gets the height of a font in twips.

This is an implementation of CGraphicsDevice::FontHeightInTwips(TInt,TInt)const.

Parameters

Return value

IMPORT_C virtual TInt FontHeightInPixels(TInt aTypefaceIndex, TInt aHeightIndex) const;

Description

Gets the height, in pixels, of the specified typeface at one of its defined heights.

This is an implementation of CBitMapDevice::FontHeightInPixels().

Parameters

Return value

IMPORT_C virtual TInt NumTypefaces() const;

Description

Gets the number of typefaces supported by the device.

Return value

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

Description

Gets information about an indexed typeface.

Parameters

See also:

• CGraphicsDevice::TypefaceSupport(TTypefaceSupport &,TInt)constGets typeface information for a specified typeface.

IMPORT_C TInt SetCustomPalette(const CPalette *aPalette);

Description

Sets the variable 8 bits per pixel colour palette, replacing the system default one. Only the entries in the system default palette which have corresponding entries in aPalette are overwritten, i.e. if aPalette contains fewer than 256 colours, some will remain unchanged. If aPalette has more than 256 entries, the additional entries are ignored.

Parameters

Return value

inline CGraphicsAccelerator* GraphicsAccelerator() const;

Description

Gets a pointer to the 2D graphics accelerator owned by the device. If one is available, it is used to accelerate various CFbsBitGc graphics operations.

Return value

See also:

• CFbsBitmapDevice::NewL(CFbsBitmap *)Allocates and constructs the device with the bitmap. Also creates a 2D graphics ...

inline CFbsBitGc::TGraphicsOrientation Orientation() const;

Description

Gets the device's orientation. The orientation can be set using CFbsBitGc::SetOrientation(TGraphicsOrientation).

Return value

IMPORT_C static TDisplayMode DisplayMode16M();

Description

Depending on the current graphics hardware this will return one of the 16M video modes defined in TDisplayMode, or ENone if a 16M video mode is not supported.

Return value

See also:

• TDisplayModeDisplay modes.

IMPORT_C TInt SetScalingFactor(const TPoint &aOrigin, TInt aFactorX, TInt aFactorY, TInt aDivisorX, TInt aDivisorY);

Description

Sets scaling factor by which the drawing device should scale the drawing images. If you want to un-scale the device, call CFbsDevice::SetScalingFactor(const TPoint &,TInt,TInt,TInt,TInt) with Origin (0,0), factorX = 1, factorY = 1, divisorX = 1, divisorY = 1.

Note: The existing graphics acceleration interface does not have support for scaling.

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

Parameters

Return value

IMPORT_C void GetDrawRect(TRect &aRect) const;

Description

Gets logical coordinates of the drawing rectangle. If the device is not scaled, logocal coordinates of the drawing rectangle are the same as its physical coordinates.

Parameters

protected: inline virtual void DrawingBegin(TBool=EFalse);

Description

Parameters

protected: inline virtual void DrawingEnd(TBool=EFalse);

Description

Parameters

protected: inline virtual void SetBits();

Description

Sets the bit level.

protected: inline virtual void CancelSprite() const;

Description

Cancels drawing the sprite.

protected: inline virtual TSpriteBase* HideSprite() const;

Description

Hides the sprite over the whole screen.

Return value

protected: inline virtual TSpriteBase* HideSprite(const TRect &, const TRegion *) const;

Description

Hides the sprite within a particular region.

Parameters

Return value

protected: inline virtual void ShowSprite(TSpriteBase *) const;

Description

Shows the specified sprite over the whole screen.

Parameters

protected: inline virtual void ShowSprite(TSpriteBase *, const TRect &, const TRegion *) const;

Description

Shows the specified sprite within a particular region.

Parameters

protected: CFbsDrawDevice * iDrawDevice;

Description

protected: RFbsSession * iFbs;

Description

protected: CFbsTypefaceStore * iTypefaceStore;

Description

protected: TInt iSpare;

Description

protected: TBool iScreenDevice;

Description

protected: TUint8 * iBitBltMaskedBuffer;

Description

protected: CGraphicsAccelerator * iGraphicsAccelerator;

Description

protected: CFbsBitGc::TGraphicsOrientation iOrientation;

Description