Ogre::GLES2StagingBuffer Class Reference

A staging buffer is a buffer that resides on the GPU and be written to/from both CPU & GPU However the access in both cases is limited. More...

#include <OgreGLES2StagingBuffer.h>

Inheritance diagram for Ogre::GLES2StagingBuffer:

Public Member Functions
	GLES2StagingBuffer (size_t internalBufferStart, size_t sizeBytes, VaoManager *vaoManager, bool uploadOnly, GLuint vboName)
virtual	~GLES2StagingBuffer ()
virtual size_t	_asyncDownload (BufferPacked *source, size_t srcOffset, size_t srcLength)
	Copies the GPU data in BufferPacked to the StagingBuffer so that it can be later read by the CPU using an AsyncTicket. More...
void	cleanUnfencedHazards ()
GLuint	getBufferName () const
virtual StagingStallType	uploadWillStall (size_t sizeBytes)
	Returns true if our next call to map() with the same parameters will stall. More...
Public Member Functions inherited from Ogre::StagingBuffer
	StagingBuffer (size_t internalBufferStart, size_t sizeBytes, VaoManager *vaoManager, bool uploadOnly)
virtual	~StagingBuffer ()
virtual void	_cancelDownload (size_t offset, size_t sizeBytes)
	Releases memory assigned to a download that hasn't been mapped yet, to make space for another _asyncDownload call. More...
const void *	_mapForRead (size_t offset, size_t sizeBytes)
	Maps the buffer for read acces for the CPU. More...
void	addReferenceCount ()
	Adds a reference count to the StagingBuffer. More...
virtual bool	canDownload (size_t length) const
	Checks if this staging buffer has enough free space to use _asyncDownload. More...
uint64	getLastUsedTimestamp () const
	Returns the time in millisecond when the ref. count became 0. More...
uint32	getLifetimeThreshold () const
	Returns the time in milliseconds in which a StagingBuffer should live with a reference count of 0 before being deleted. More...
MappingState	getMappingState () const
size_t	getMaxSize ()
int16	getReferenceCount () const
uint32	getUnfencedTimeThreshold () const
	Returns the time in milliseconds in which a StagingBuffer should hazards unfenced while with a reference count of 0. More...
bool	getUploadOnly () const
	When true, this buffer can only be used for uploading to GPU. More...
void *	map (size_t sizeBytes)
	Maps the given amount of bytes. More...
void	removeReferenceCount ()
	Decreases the reference count by one. More...
void	unmap (const Destination &destination)
	Unmaps the mapped region and copies the data to the given region. More...
void	unmap (const Destination *destinations, size_t numDestinations)
void	unmap (const DestinationVec &destinations)
	Unmaps the mapped region and copies the data to multiple buffers. More...

Additional Inherited Members
Public Types inherited from Ogre::StagingBuffer
typedef vector< Destination >::type	DestinationVec

Detailed Description

A staging buffer is a buffer that resides on the GPU and be written to/from both CPU & GPU However the access in both cases is limited.

GPUs can only copy (i.e. memcpy) to another real buffer (can't be used directly as i.e. texture or vertex buffer) and CPUs can only map it. In other words, a staging buffer is an intermediate buffer to transfer data between CPU & GPU

Constructor & Destructor Documentation

GLES2StagingBuffer()

Ogre::GLES2StagingBuffer::GLES2StagingBuffer	(	size_t	internalBufferStart,
		size_t	sizeBytes,
		VaoManager *	vaoManager,
		bool	uploadOnly,
		GLuint	vboName
	)

~GLES2StagingBuffer()

virtual Ogre::GLES2StagingBuffer::~GLES2StagingBuffer ( )

virtual

Member Function Documentation

_asyncDownload()

virtual size_t Ogre::GLES2StagingBuffer::_asyncDownload ( BufferPacked *  source, size_t  srcOffset, size_t  srcLength  )

virtual

Copies the GPU data in BufferPacked to the StagingBuffer so that it can be later read by the CPU using an AsyncTicket.

See also

AsyncTicket.

Remarks

For internal use. May throw if it can't handle the request (i.e. requested size is too big, or too many _asyncDownload operations are pending until calling _mapForRead)

See also

canDownload mUploadOnly must be true.

Parameters

source	The buffer to copy from.
srcOffset	The offset, in bytes, of the buffer to copy from.
srcLength	The size in bytes, of the data to transfer to this staging buffer.

Returns

The offset in bytes that will be used by

See also

_mapForRead

Implements Ogre::StagingBuffer.

cleanUnfencedHazards()

void Ogre::GLES2StagingBuffer::cleanUnfencedHazards

(

)

getBufferName()

GLuint Ogre::GLES2StagingBuffer::getBufferName ( ) const

inline

uploadWillStall()

virtual StagingStallType Ogre::GLES2StagingBuffer::uploadWillStall ( size_t  sizeBytes )

virtual

Returns true if our next call to map() with the same parameters will stall.

See also

StagingStallType

Remarks

Not all RenderSystems can accurately give this information and will always return STALL_PARTIAL (i.e. GLES2) The chances of getting a STALL_FULL get higher as sizeBytes gets closer to this->getMaxSize() mUploadOnly must be false. It is the counter side of

See also

canDownload

Reimplemented from Ogre::StagingBuffer.

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The documentation for this class was generated from the following file:

• OgreGLES2StagingBuffer.h