FCompositeBuffer Class Reference

#include <CompositeBuffer.h>

Public Member Functions
template<typename... BufferTypes, std::enable_if_t< std::conjunction_v< CanAppendBufferType< std::decay_t< BufferTypes > >... > > * = nullptr>
	FCompositeBuffer (BufferTypes &&... Buffers)
CORE_API	~FCompositeBuffer ()
CORE_API void	Reset ()
CORE_API uint64	GetSize () const
TConstArrayView< FSharedBuffer >	GetSegments () const
	operator bool () const
bool	IsNull () const
CORE_API bool	IsOwned () const
CORE_API FCompositeBuffer	MakeOwned () const &
CORE_API FCompositeBuffer	MakeOwned () &&
CORE_API FSharedBuffer	ToShared () const &
CORE_API FSharedBuffer	ToShared () &&
CORE_API FCompositeBuffer	Mid (uint64 Offset, uint64 Size=MAX_uint64) const
CORE_API FMemoryView	ViewOrCopyRange (uint64 Offset, uint64 Size, FUniqueBuffer &CopyBuffer) const
CORE_API FMemoryView	ViewOrCopyRange (uint64 Offset, uint64 Size, FUniqueBuffer &CopyBuffer, TFunctionRef< FUniqueBuffer(uint64 Size)> Allocator) const
CORE_API void	CopyTo (FMutableMemoryView Target, uint64 Offset=0) const
CORE_API void	IterateRange (uint64 Offset, uint64 Size, TFunctionRef< void(FMemoryView View)> Visitor) const
CORE_API void	IterateRange (uint64 Offset, uint64 Size, TFunctionRef< void(FMemoryView View, const FSharedBuffer &ViewOuter)> Visitor) const
CORE_API bool	EqualBytes (const FCompositeBuffer &Other) const

Static Public Attributes
static CORE_API const FCompositeBuffer	Null

Detailed Description

FCompositeBuffer is a non-contiguous buffer composed of zero or more immutable shared buffers.

A composite buffer is most efficient when its segments are consumed as they are, but it can be flattened into a contiguous buffer when necessary, by calling ToShared(). Ownership of segment buffers is not changed on construction, but if ownership of segments is required then that can be guaranteed by calling MakeOwned().

Constructor & Destructor Documentation

FCompositeBuffer()

template<typename... BufferTypes, std::enable_if_t< std::conjunction_v< CanAppendBufferType< std::decay_t< BufferTypes > >... > > * = nullptr>

FCompositeBuffer::FCompositeBuffer ( BufferTypes &&...  Buffers )

inlineexplicit

Construct a composite buffer by concatenating the buffers. Does not enforce ownership.

Buffer parameters may be FSharedBuffer, FCompositeBuffer, or TArray<FSharedBuffer>.

~FCompositeBuffer()

FCompositeBuffer::~FCompositeBuffer ( )

default

Destructor.

Member Function Documentation

CopyTo()

void FCompositeBuffer::CopyTo	(	FMutableMemoryView	Target,
		uint64	Offset = 0
	)		const

Copies a range of the buffer to a contiguous region of memory.

Parameters

Target	The view to copy to. Must be no larger than the data available at the offset.
Offset	The byte offset in this buffer to start copying from.

EqualBytes()

bool FCompositeBuffer::EqualBytes

(

const FCompositeBuffer &

Other

)

const

Returns true if the bytes of this buffer are equal to the bytes of the other buffer.

GetSegments()

TConstArrayView< FSharedBuffer > FCompositeBuffer::GetSegments ( ) const

inline

Returns the segments that the buffer is composed from.

GetSize()

uint64 FCompositeBuffer::GetSize

(

)

const

Returns the total size of the composite buffer in bytes.

IsNull()

bool FCompositeBuffer::IsNull ( ) const

inline

Returns true if the composite buffer is null.

IsOwned()

bool FCompositeBuffer::IsOwned

(

)

const

Returns true if every segment in the composite buffer is owned.

IterateRange() [1/2]

void FCompositeBuffer::IterateRange	(	uint64	Offset,
		uint64	Size,
		TFunctionRef< void(FMemoryView View)>	Visitor
	)		const

Invokes a visitor with a view of each segment that intersects with a range.

Parameters

Offset	The byte offset in this buffer to start visiting from.
Size	The number of bytes in the range to visit.
Visitor	The visitor to invoke from zero to GetSegments().Num() times.

IterateRange() [2/2]

void FCompositeBuffer::IterateRange	(	uint64	Offset,
		uint64	Size,
		TFunctionRef< void(FMemoryView View, const FSharedBuffer &ViewOuter)>	Visitor
	)		const

MakeOwned() [1/2]

FCompositeBuffer FCompositeBuffer::MakeOwned

(

)

&&

MakeOwned() [2/2]

FCompositeBuffer FCompositeBuffer::MakeOwned

(

)

const &

Returns a copy of the buffer where every segment is owned.

Mid()

FCompositeBuffer FCompositeBuffer::Mid	(	uint64	Offset,
		uint64	Size = MAX_uint64
	)		const

Returns the middle part of the buffer by taking the size starting at the offset.

operator bool()

FCompositeBuffer::operator bool ( ) const

inlineexplicit

Returns true if the composite buffer is not null.

Reset()

void FCompositeBuffer::Reset

(

)

Reset this to null.

ToShared() [1/2]

FSharedBuffer FCompositeBuffer::ToShared

(

)

&&

ToShared() [2/2]

FSharedBuffer FCompositeBuffer::ToShared

(

)

const &

Returns the concatenation of the segments into a contiguous buffer.

ViewOrCopyRange() [1/2]

FMemoryView FCompositeBuffer::ViewOrCopyRange	(	uint64	Offset,
		uint64	Size,
		FUniqueBuffer &	CopyBuffer
	)		const

Returns a view of the range if contained by one segment, otherwise a view of a copy of the range.

Note

CopyBuffer is reused if large enough, and otherwise allocated when needed.

Parameters

Offset	The byte offset in this buffer that the range starts at.
Size	The number of bytes in the range to view or copy.
CopyBuffer	The buffer to write the copy into if a copy is required.
Allocator	The optional allocator to use when the copy buffer is required.

ViewOrCopyRange() [2/2]

FMemoryView FCompositeBuffer::ViewOrCopyRange	(	uint64	Offset,
		uint64	Size,
		FUniqueBuffer &	CopyBuffer,
		TFunctionRef< FUniqueBuffer(uint64 Size)>	Allocator
	)		const

Member Data Documentation

Null

const FCompositeBuffer FCompositeBuffer::Null

static

A null composite buffer.

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

• Engine/Source/Runtime/Core/Public/Memory/CompositeBuffer.h
• Engine/Source/Runtime/Core/Private/Memory/CompositeBuffer.cpp