FLandscapeEditLayerReadback Class Reference

#include <LandscapeEditReadback.h>

Classes
struct	FComponentReadbackContext

Public Types
using	FPerChannelLayerNames = TStaticArray< FName, 4 >
using	FReadbackContext = TArray< FComponentReadbackContext >

Public Member Functions
	FLandscapeEditLayerReadback ()
	~FLandscapeEditLayerReadback ()
bool	SetHash (uint64 InHash)
uint64	GetHash () const
void	Enqueue (UTexture2D const *InSourceTexture, FReadbackContext &&InReadbackContext)
void	Tick ()
void	Flush ()
int32	GetCompletedResultNum () const
TArray< TArray< FColor > > const &	GetResult (int32 InResultIndex) const
FReadbackContext const &	GetResultContext (int32 InResultIndex) const
void	ReleaseCompletedResults (int32 InResultNum)

Static Public Member Functions
static bool	HasWork ()
static void	GarbageCollectTasks ()
static void	FlushAllReadbackTasks ()

Detailed Description

Read back queue for a landscape edit layer texture. This handles reading landscape edit data back from the GPU to the game thread. Multiple read backs can be queued in a single object and any completed results can be retrieved. Tick() must be called regularly to update the internal read back tasks. When results are available GetCompletedResultNum() will be greater than zero. After getting latest results with GetResult()/GetResultContext() you should call ReleaseCompletedResults() to prevent leaks.

Member Typedef Documentation

FPerChannelLayerNames

using FLandscapeEditLayerReadback::FPerChannelLayerNames = TStaticArray<FName, 4>

FReadbackContext

using FLandscapeEditLayerReadback::FReadbackContext = TArray<FComponentReadbackContext>

Full context for processing read back results.

Constructor & Destructor Documentation

FLandscapeEditLayerReadback()

FLandscapeEditLayerReadback::FLandscapeEditLayerReadback

(

)

~FLandscapeEditLayerReadback()

FLandscapeEditLayerReadback::~FLandscapeEditLayerReadback

(

)

Member Function Documentation

Enqueue()

void FLandscapeEditLayerReadback::Enqueue	(	UTexture2D const *	InSourceTexture,
		FReadbackContext &&	InReadbackContext
	)

Queue a new texture to read back. The GPU copy will be queued to the render thread inside this function.

Flush()

void FLandscapeEditLayerReadback::Flush

(

)

FlushAllReadbackTasks()

void FLandscapeEditLayerReadback::FlushAllReadbackTasks ( )

static

Brute-force flush of all pending readback tasks. Use this when you want to make sure all readbacks are performed. In case of multiple readbacks, this is much more efficient than individually flushing each task.

GarbageCollectTasks()

void FLandscapeEditLayerReadback::GarbageCollectTasks ( )

static

Optional call to allow garbage collection of any task resources and check for leaks. Call once per frame.

GetCompletedResultNum()

int32 FLandscapeEditLayerReadback::GetCompletedResultNum

(

)

const

Returns a value greater than 0 if there are completed read back tasks for which we can retrieve results.

GetHash()

uint64 FLandscapeEditLayerReadback::GetHash ( ) const

inline

Get the stored hash value.

GetResult()

TArray< TArray< FColor > > const & FLandscapeEditLayerReadback::GetResult

(

int32

InResultIndex

)

const

Get the result for the completed task index. Returned reference will be valid until we next call ReleaseCompletedResults().

GetResultContext()

FLandscapeEditLayerReadback::FReadbackContext const & FLandscapeEditLayerReadback::GetResultContext

(

int32

InResultIndex

)

const

Get the result context for the completed task index. Returned reference will be valid until we next call ReleaseCompletedResults().

HasWork()

bool FLandscapeEditLayerReadback::HasWork ( )

static

Returns true if there are any queued tasks that haven't been released.

ReleaseCompletedResults()

void FLandscapeEditLayerReadback::ReleaseCompletedResults

(

int32

InResultNum

)

SetHash()

bool FLandscapeEditLayerReadback::SetHash

(

uint64

InHash

)

Update the stored hash value. Return true if this changes the value.

Tick()

void FLandscapeEditLayerReadback::Tick

(

)

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

• Engine/Source/Runtime/Landscape/Private/LandscapeEditReadback.h
• Engine/Source/Runtime/Landscape/Private/LandscapeEditReadback.cpp