FTextureMipAllocator Class Reference

#include <TextureMipAllocator.h>

Inheritance diagram for FTextureMipAllocator:

Public Types
enum class	ETickState : uint32 { AllocateMips , UploadMips , Done }
enum class	ETickThread : uint32 { Async , Render , None }

Public Member Functions
	FTextureMipAllocator (UTexture *Texture, ETickState InTickState, ETickThread InTickThread)
	FTextureMipAllocator (const FTextureMipAllocator &)
	FTextureMipAllocator (FTextureMipAllocator &&)
virtual	~FTextureMipAllocator ()
FORCEINLINE ETickState	GetNextTickState () const
FORCEINLINE ETickThread	GetNextTickThread () const
virtual bool	AllocateMips (const FTextureUpdateContext &Context, FTextureMipInfoArray &OutMipInfos, const FTextureUpdateSyncOptions &SyncOptions)=0
virtual bool	UploadMips (const FTextureUpdateContext &Context, const FTextureUpdateSyncOptions &SyncOptions)=0
bool	FinalizeMips (const FTextureUpdateContext &Context, const FTextureUpdateSyncOptions &SyncOptions)
void	ExecuteCancel (const FTextureUpdateSyncOptions &SyncOptions)
ETickThread	ExecuteGetCancelThread () const
const FTextureRHIRef &	GetIntermediateTextureRHI () const

Protected Member Functions
virtual void	Cancel (const FTextureUpdateSyncOptions &SyncOptions)=0
virtual ETickThread	GetCancelThread () const =0
FORCEINLINE void	AdvanceTo (ETickState InState, ETickThread InThread)

Protected Attributes
const FStreamableRenderResourceState	ResourceState
const int32	CurrentFirstLODIdx = INDEX_NONE
const int32	PendingFirstLODIdx = INDEX_NONE
FTextureRHIRef	IntermediateTextureRHI

Detailed Description

FTextureMipAllocator defines the update steps and interface to implement the mip allocation strategy used in FTextureStreamIn. It allows to decouples the texture creation steps from the texture update. Typical implementations are using RHIAsyncCreateTexture2D, RHIAsyncReallocateTexture2D or virtual textures.

Member Enumeration Documentation

ETickState

enum class FTextureMipAllocator::ETickState : uint32

strong

Enumerator
AllocateMips
UploadMips
Done

ETickThread

enum class FTextureMipAllocator::ETickThread : uint32

strong

Enumerator
Async
Render
None

Constructor & Destructor Documentation

FTextureMipAllocator() [1/3]

FTextureMipAllocator::FTextureMipAllocator	(	UTexture *	Texture,
		ETickState	InTickState,
		ETickThread	InTickThread
	)

FTextureMipAllocator() [2/3]

FTextureMipAllocator::FTextureMipAllocator ( const FTextureMipAllocator &  )

default

FTextureMipAllocator() [3/3]

FTextureMipAllocator::FTextureMipAllocator ( FTextureMipAllocator &&  )

default

~FTextureMipAllocator()

FTextureMipAllocator::~FTextureMipAllocator ( )

virtualdefault

Member Function Documentation

AdvanceTo()

FORCEINLINE void FTextureMipAllocator::AdvanceTo ( ETickState  InState, ETickThread  InThread  )

inlineprotected

AllocateMips()

virtual bool FTextureMipAllocator::AllocateMips ( const FTextureUpdateContext &  Context, FTextureMipInfoArray &  OutMipInfos, const FTextureUpdateSyncOptions &  SyncOptions  )

pure virtual

Allocate the FTextureMipInfoArray and configure the entries for the new (streamed in) mips. In particular, the FTextureMipAllocator must set valid FTextureMipInfo::DestData so that the mip data provider can write the mip data to.

Parameters

Context	- An update context constant throughout the FTextureStreamIn update. Gives things like which texture asset is updated and what mips are streamed in.
OutMipInfos	- The array of FTextureMipInfo that must be correctly configured so that FTextureMipDataProvider know what is being requested and where to write data to.
SyncOptions	- Different sync options to control when the next tick of FTextureStreamIn can be scheduled.

Return true unless the texture update needs to be aborted because of invalid data or setup.

Implemented in FTexture2DArrayMipAllocator_Reallocate, FTexture2DMipAllocator_AsyncCreate, FTexture2DMipAllocator_AsyncReallocate, FTexture2DMipAllocator_Virtual, and FVolumeTextureMipAllocator_Reallocate.

Cancel()

virtual void FTextureMipAllocator::Cancel ( const FTextureUpdateSyncOptions &  SyncOptions )

protectedpure virtual

Cancel the progression and release any temporary resources. Called within the FTextureStreamIn update when the stream in request is aborted or cannot complete correctly The Cancel() function is called on the thread returned by GetCancelThread().

Parameters

SyncOptions

- Different sync options to control when the next tick of FTextureStreamIn can be scheduled.

Implemented in FTexture2DArrayMipAllocator_Reallocate, FTexture2DMipAllocator_AsyncCreate, FTexture2DMipAllocator_AsyncReallocate, FTexture2DMipAllocator_Virtual, and FVolumeTextureMipAllocator_Reallocate.

ExecuteCancel()

void FTextureMipAllocator::ExecuteCancel

(

const FTextureUpdateSyncOptions &

SyncOptions

)

ExecuteGetCancelThread()

FTextureMipAllocator::ETickThread FTextureMipAllocator::ExecuteGetCancelThread

(

)

const

FinalizeMips()

bool FTextureMipAllocator::FinalizeMips	(	const FTextureUpdateContext &	Context,
		const FTextureUpdateSyncOptions &	SyncOptions
	)

Update the texture resource with the new RHI texture. Update is completed after this step and can not be canceled afterward..

Parameters

Context	- An update context constant throughout the FTextureStreamIn update. Gives things like which texture asset is updated and what mips are streamed in.
SyncOptions	- Different sync options to control when the next tick of FTextureStreamIn can be scheduled.

Return true unless the texture update needs to be aborted because of invalid data or setup.

GetCancelThread()

virtual ETickThread FTextureMipAllocator::GetCancelThread ( ) const

protectedpure virtual

Implemented in FTexture2DArrayMipAllocator_Reallocate, FTexture2DMipAllocator_AsyncCreate, FTexture2DMipAllocator_AsyncReallocate, FTexture2DMipAllocator_Virtual, and FVolumeTextureMipAllocator_Reallocate.

GetIntermediateTextureRHI()

const FTextureRHIRef & FTextureMipAllocator::GetIntermediateTextureRHI ( ) const

inline

GetNextTickState()

FORCEINLINE ETickState FTextureMipAllocator::GetNextTickState ( ) const

inline

GetNextTickThread()

FORCEINLINE ETickThread FTextureMipAllocator::GetNextTickThread ( ) const

inline

UploadMips()

virtual bool FTextureMipAllocator::UploadMips ( const FTextureUpdateContext &  Context, const FTextureUpdateSyncOptions &  SyncOptions  )

pure virtual

Upload the new mip data to the GPU. The

Parameters

Context	- An update context constant throughout the FTextureStreamIn update. Gives things like which texture asset is updated and what mips are streamed in.
SyncOptions	- Different sync options to control when the next tick of FTextureStreamIn can be scheduled.

Return true unless the texture update needs to be aborted because of invalid data or setup.

Implemented in FTexture2DArrayMipAllocator_Reallocate, FTexture2DMipAllocator_AsyncCreate, FTexture2DMipAllocator_AsyncReallocate, FTexture2DMipAllocator_Virtual, and FVolumeTextureMipAllocator_Reallocate.

Member Data Documentation

CurrentFirstLODIdx

const int32 FTextureMipAllocator::CurrentFirstLODIdx = INDEX_NONE

protected

IntermediateTextureRHI

FTextureRHIRef FTextureMipAllocator::IntermediateTextureRHI

protected

The intermediate texture async created in the update process.

PendingFirstLODIdx

const int32 FTextureMipAllocator::PendingFirstLODIdx = INDEX_NONE

protected

ResourceState

const FStreamableRenderResourceState FTextureMipAllocator::ResourceState

protected

The streamable state requested.

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

• Engine/Source/Runtime/Engine/Private/Streaming/TextureMipAllocator.h
• Engine/Source/Runtime/Engine/Private/Streaming/TextureMipAllocator.cpp