FCompressedGrowableBuffer Struct Reference

#include <CompressedGrowableBuffer.h>

Public Member Functions
CORE_API	FCompressedGrowableBuffer (int32 MaxPendingBufferSize, FName CompressionFormat, ECompressionFlags CompressionFlags=COMPRESS_None)
CORE_API void	Lock ()
CORE_API void	Unlock ()
CORE_API int32	Append (void *Data, int32 Size)
CORE_API void *	Access (int32 Offset)
int32	Num () const
SIZE_T	GetAllocatedSize () const

Detailed Description

Growable compressed buffer. Usage is to append frequently but only request and therefore decompress very infrequently. The prime usage case is the memory profiler keeping track of full call stacks.

Constructor & Destructor Documentation

FCompressedGrowableBuffer()

FCompressedGrowableBuffer::FCompressedGrowableBuffer	(	int32	MaxPendingBufferSize,
		FName	CompressionFormat,
		ECompressionFlags	CompressionFlags = COMPRESS_None
	)

Constructor

Parameters

MaxPendingBufferSize	Max chunk size to compress in uncompressed bytes
CompressionFlags	Compression flags to compress memory with

Member Function Documentation

Access()

void * FCompressedGrowableBuffer::Access

(

int32

Offset

)

Accesses the data at passed in offset and returns it. The memory is read-only and memory will be freed in call to unlock. The lifetime of the data is till the next call to Unlock, Append or Access

Parameters

Offset

Offset to return corresponding data for

Append()

int32 FCompressedGrowableBuffer::Append	(	void *	Data,
		int32	Size
	)

Appends passed in data to the buffer. The data needs to be less than the max pending buffer size. The code will assert on this assumption.

Parameters

Data	Data to append
Size	Size of data in bytes.

Returns

Offset of data, used for retrieval later on

Appends passed in data to the buffer. The data needs to be less than the max pending buffer size. The code will assert on this assumption.

Parameters

Data	Data to append
Size	Size of data in bytes.

Returns

Offset of data, used for retrieval later on

GetAllocatedSize()

SIZE_T FCompressedGrowableBuffer::GetAllocatedSize ( ) const

inline

Helper function to return the amount of memory allocated by this buffer

Returns

number of bytes allocated by this buffer

Lock()

void FCompressedGrowableBuffer::Lock

(

)

Locks the buffer for reading. Needs to be called before calls to Access and needs to be matched up with Unlock call.

Num()

int32 FCompressedGrowableBuffer::Num ( ) const

inline

Returns

Number of entries appended.

Unlock()

void FCompressedGrowableBuffer::Unlock

(

)

Unlocks the buffer and frees temporary resources used for accessing.

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

• Engine/Source/Runtime/Core/Public/Misc/CompressedGrowableBuffer.h
• Engine/Source/Runtime/Core/Private/Misc/Compression.cpp