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MSgImageAdapter Class Reference

class MSgImageAdapter : public MSgDrawableAdapter

This interface must be implemented by all the user-side objects in the adaptation layer of the Graphics subsystem which are referenced by instances of RSgImage. The interface between the user-side and the kernel-side parts of the adaptation layer is outside the scope of the specification of the Graphics Resource API.

RSgImage

Inherits from

MSgImageAdapter
- MSgDrawableAdapter
  - MSgResourceAdapter

Public Member Functions
TInt	GetInfo (TSgImageInfo &)
TInt	MapReadOnly (const TAny *&, TInt &)
TInt	MapReadWrite ( TAny *&, TInt &)
TInt	MapWriteOnly ( TAny *&, TInt &)
TInt	Unmap ()

Inherited Functions
	MSgDrawableAdapter::DrawableType()const
	MSgDrawableAdapter::GetInterface(TUid,TAny *&)
	MSgDrawableAdapter::Id()const
	MSgResourceAdapter::Close()

Member Functions Documentation

GetInfo(TSgImageInfo &)

TInt

GetInfo

(

TSgImageInfo &

aInfo

)

const [pure virtual]

Retrieves the values of the attributes of the image represented by this adapter object.

Pre-condition: If aInfo.iUserAttributes is not null then it points to an array of aInfo.iUserAttributeCount elements with globally unique identifiers corresponding to user-defined attributes attached to the image.

RSgImage::GetInfo()

Parameters

TSgImageInfo & aInfo

On input, the globally unique identifiers of the user-defined attributes to be retrieved from the image, if any. On return, the values of the attributes of the image and the values of the selected user-defined attributes.

MapReadOnly(const TAny *&, TInt &)

TInt	MapReadOnly	(	const TAny *&	aDataAddress,
			TInt &	aDataStride
		)	[pure virtual]

Temporarily makes the pixel data of the image represented by this adapter object accessible for reading by the CPU.

Pre-condition: The image is not mapped yet.; The image was created with CPU access ESgCpuAccessReadOnly or ESgCpuAccessReadWrite.; The image was created by the calling process.

Post-condition: The pixel data of the image is directly accessible in the address space of the calling process for reading only, until Unmap() is called.

RSgImage::MapReadOnly()

Parameters

const TAny *& aDataAddress	On return, the base address of the pixel data in the address space of the calling process.
TInt & aDataStride	On return, the number of bytes between rows of the pixel data.

MapReadWrite(TAny *&, TInt &)

TInt	MapReadWrite	(	TAny *&	aDataAddress,
			TInt &	aDataStride
		)	[pure virtual]

Temporarily makes the pixel data of the image represented by this adapter object accessible for reading and writing by the CPU.

Pre-condition: The image is not mapped yet.; The image was created with CPU access ESgCpuAccessReadWrite.; The image was created by the calling process.

Post-condition: The pixel data of the image is directly accessible in the address space of the calling process for reading and writing, until Unmap() is called.

RSgImage::MapReadWrite()

Parameters

TAny *& aDataAddress	On return, the base address of the pixel data in the address space of the calling process.
TInt & aDataStride	On return, the number of bytes between rows of the pixel data.

MapWriteOnly(TAny *&, TInt &)

TInt	MapWriteOnly	(	TAny *&	aDataAddress,
			TInt &	aDataStride
		)	[pure virtual]

Temporarily makes the pixel data of the image represented by this adapter object accessible for writing by the CPU.

Pre-condition: The image is not mapped yet.; The image was created with CPU access ESgCpuAccessWriteOnly or ESgCpuAccessReadWrite.; The image was created by the calling process.

Post-condition: The pixel data of the image is directly accessible in the address space of the calling process for writing only, until Unmap() is called.

RSgImage::MapWriteOnly()

Parameters

TAny *& aDataAddress	On return, the base address of the pixel data in the address space of the calling process.
TInt & aDataStride	On return, the number of bytes between rows of the pixel data.

Unmap()

TInt

Unmap

(

)

[pure virtual]

Makes the pixel data of the image represented by this adapter object no longer accessible by the CPU.

Pre-condition: The image is mapped for CPU access by a previous call to MapReadOnly() , MapWriteOnly() or MapReadWrite() .

Post-condition: The GPU is guaranteed to be able to get access to the image.; The address range in the calling process used for the mapping is no longer valid.

RSgImage::Unmap()