CGraphicsAccelerator Class Reference

class CGraphicsAccelerator : public CBase

Abstract base class for 2D graphics accelerators.

This class can be derived from to provide accelerated implementations of some common 2D graphics algorithms. Support for accelerated 2D graphics has been integrated into existing classes in the Graphics API for instance CFbsBitGc, so that existing code does not need to be altered, but a graphics accelerator can be used directly by applications. The accelerated 2D graphics operations may be implemented in software, hardware, or both.

Inherits from

  • CGraphicsAccelerator

Member Functions Documentation

Capabilities()

const TGraphicsAcceleratorCaps *Capabilities()[pure virtual]

Returns the capabilities of the graphics accelerator.

Operation(const TGraphicsOperation &)

TInt Operation(const TGraphicsOperation &aOperation)[pure virtual]

Requests the graphics accelerator to perform a single graphics operation.

Parameters

const TGraphicsOperation & aOperationAn instance of a TGraphicsOperation-derived class that identifies the graphics operation to be performed.

Operation(const TGraphicsOperation &, TInt, TRect *)

TInt Operation(const TGraphicsOperation &aOperation,
TIntaNumClipRects,
TRect *aClipRects
)[pure virtual]

Requests the graphics accelerator perform a single graphics operation within a clipping region. This version is of Operation() is only usable if the accelerator capabilities returned by Capabilities() indicate that clipping to a region is supported.

TGraphicsAcceleratorCaps::iClipping

Parameters

const TGraphicsOperation & aOperationAn instance of a TGraphicsOperation-derived class that identifies the graphics operation to be performed.
TInt aNumClipRectsThe number of rectangles in the clipping region.
TRect * aClipRectsA pointer to the first rectangle in the clipping region.

Operation(TDes8 &)

TInt Operation(TDes8 &aBuffer)[pure virtual]

Requests the graphics accelerator perform one or more graphics operations contained in a buffer.

The underlying implementation may be able to process a group of graphics operations more efficiently than if Operation() was called for each individually.

This function should be implemented as if Operation() was called in turn for each operation contained in the buffer. Each operation should be carried out immediately after the one preceding it. If a method returns an error, the length of aBuffer should be set to indicate the number of operations that have been successfully processed. In this case, the operation in which the error occurred will be indicated by the memory address &aBuffer[aBuffer.Length()].

Parameters

TDes8 & aBufferA descriptor which holds a concatenation of graphics operations (TGraphicsOperation-derived objects).

Operation(TDes8 &, TInt, TRect *)

TInt Operation(TDes8 &aBuffer,
TIntaNumClipRects,
TRect *aClipRects
)[pure virtual]

Requests the graphics accelerator perform one or more graphics operations within a clipping region. This version is of Operation() is only usable if the accelerator capabilities returned by Capabilities() indicate that clipping to a region is supported.

The underlying implementation may be able to process a group of graphics operations more efficiently than if Operation() was called for each individually.

This function should be implemented as if Operation() was called in turn for each operation contained in the buffer. Each operation should be carried out immediately after the one preceding it. If a method returns an error, the length of aBuffer should be set to indicate the number of operations that have been successfully processed. In this case, the operation in which the error occurred will be indicated by the memory address &aBuffer[aBuffer.Length()].

TGraphicsAcceleratorCaps::iClipping

Parameters

TDes8 & aBufferA descriptor which holds a concatenation of graphics operations (TGraphicsOperation objects).
TInt aNumClipRectsThe number of rectangles in the clipping region.
TRect * aClipRectsA pointer to the first rectangle in the clipping region.

Reserved_1()

voidReserved_1()[pure virtual]

Reserved_2()

voidReserved_2()[pure virtual]

Reserved_3()

voidReserved_3()[pure virtual]

Reserved_4()

voidReserved_4()[pure virtual]