GPUSort.cpp File Reference

#include "GPUSort.h"
#include "Math/RandomStream.h"
#include "RHIBreadcrumbs.h"
#include "RenderingThread.h"
#include "RHIContext.h"
#include "ShaderCompilerCore.h"
#include "ShaderParameterMacros.h"
#include "ShaderParameterUtils.h"
#include "GlobalShader.h"
#include "PipelineStateCache.h"
#include "ProfilingDebugging/RealtimeGPUProfiler.h"

Classes
class	FSortOffsetBuffers
class	FRadixSortParametersBuffer
class	FRadixSortClearOffsetsCS
class	FRadixSortUpsweepCS
class	FRadixSortSpineCS
class	FRadixSortDownsweepCS

Macros
#define	GPUSORT_BITCOUNT   32
#define	RADIX_BITS   4
#define	DIGIT_COUNT   (1 << RADIX_BITS)
#define	KEYS_PER_LOOP   8
#define	THREAD_COUNT   128
#define	TILE_SIZE   (THREAD_COUNT * KEYS_PER_LOOP)
#define	MAX_GROUP_COUNT   64
#define	MAX_PASS_COUNT   (32 / RADIX_BITS)

Typedefs
typedef TUniformBufferRef< FRadixSortParameters >	FRadixSortUniformBufferRef

Enumerations
enum	{ GPU_SORT_TEST_SIZE_SMALL = (1 << 9) , GPU_SORT_TEST_SIZE_LARGE = (1 << 20) , GPU_SORT_TEST_SIZE_MIN = (1 << 4) , GPU_SORT_TEST_SIZE_MAX = (1 << 20) }

Functions
	DEFINE_LOG_CATEGORY_STATIC (LogGPUSort, Log, All)
void	SetRadixSortShaderCompilerEnvironment (FShaderCompilerEnvironment &OutEnvironment)
	IMPLEMENT_GLOBAL_SHADER_PARAMETER_STRUCT (FRadixSortParameters,"RadixSortUB")
	IMPLEMENT_SHADER_TYPE (, FRadixSortClearOffsetsCS, TEXT("/Engine/Private/RadixSortShaders.usf"), TEXT("RadixSort_ClearOffsets"), SF_Compute)
	IMPLEMENT_SHADER_TYPE (, FRadixSortUpsweepCS, TEXT("/Engine/Private/RadixSortShaders.usf"), TEXT("RadixSort_Upsweep"), SF_Compute)
	IMPLEMENT_SHADER_TYPE (, FRadixSortSpineCS, TEXT("/Engine/Private/RadixSortShaders.usf"), TEXT("RadixSort_Spine"), SF_Compute)
	IMPLEMENT_SHADER_TYPE (, FRadixSortDownsweepCS, TEXT("/Engine/Private/RadixSortShaders.usf"), TEXT("RadixSort_Downsweep"), SF_Compute)
int32	GetGPUSortPassCount (uint32 KeyMask)
int32	SortGPUBuffers (FRHICommandList &RHICmdList, FGPUSortBuffers SortBuffers, int32 BufferIndex, uint32 KeyMask, int32 Count, ERHIFeatureLevel::Type FeatureLevel)
void	TestGPUSort (EGPUSortTest TestToRun, ERHIFeatureLevel::Type FeatureLevel)

Variables
TGlobalResource< FSortOffsetBuffers >	GSortOffsetBuffers
TGlobalResource< FRadixSortParametersBuffer >	GRadixSortParametersBuffer

Macro Definition Documentation

DIGIT_COUNT

#define DIGIT_COUNT   (1 << RADIX_BITS)

GPUSORT_BITCOUNT

#define GPUSORT_BITCOUNT   32

KEYS_PER_LOOP

#define KEYS_PER_LOOP   8

MAX_GROUP_COUNT

#define MAX_GROUP_COUNT   64

MAX_PASS_COUNT

#define MAX_PASS_COUNT   (32 / RADIX_BITS)

RADIX_BITS

#define RADIX_BITS   4

THREAD_COUNT

#define THREAD_COUNT   128

TILE_SIZE

#define TILE_SIZE   (THREAD_COUNT * KEYS_PER_LOOP)

Typedef Documentation

FRadixSortUniformBufferRef

typedef TUniformBufferRef<FRadixSortParameters> FRadixSortUniformBufferRef

Enumeration Type Documentation

anonymous enum

anonymous enum

Enumerator
GPU_SORT_TEST_SIZE_SMALL
GPU_SORT_TEST_SIZE_LARGE
GPU_SORT_TEST_SIZE_MIN
GPU_SORT_TEST_SIZE_MAX

Function Documentation

DEFINE_LOG_CATEGORY_STATIC()

DEFINE_LOG_CATEGORY_STATIC	(	LogGPUSort	,
		Log	,
		All
	)

GetGPUSortPassCount()

int32 GetGPUSortPassCount

(

uint32

KeyMask

)

Get the number of passes we will need to make in order to sort

IMPLEMENT_GLOBAL_SHADER_PARAMETER_STRUCT()

IMPLEMENT_GLOBAL_SHADER_PARAMETER_STRUCT	(	FRadixSortParameters	,
		"RadixSortUB"
	)

IMPLEMENT_SHADER_TYPE() [1/4]

IMPLEMENT_SHADER_TYPE	(	FRadixSortClearOffsetsCS	,
		TEXT("/Engine/Private/RadixSortShaders.usf")	,
		TEXT("RadixSort_ClearOffsets")	,
		SF_Compute
	)

IMPLEMENT_SHADER_TYPE() [2/4]

IMPLEMENT_SHADER_TYPE	(	FRadixSortDownsweepCS	,
		TEXT("/Engine/Private/RadixSortShaders.usf")	,
		TEXT("RadixSort_Downsweep")	,
		SF_Compute
	)

IMPLEMENT_SHADER_TYPE() [3/4]

IMPLEMENT_SHADER_TYPE	(	FRadixSortSpineCS	,
		TEXT("/Engine/Private/RadixSortShaders.usf")	,
		TEXT("RadixSort_Spine")	,
		SF_Compute
	)

IMPLEMENT_SHADER_TYPE() [4/4]

IMPLEMENT_SHADER_TYPE	(	FRadixSortUpsweepCS	,
		TEXT("/Engine/Private/RadixSortShaders.usf")	,
		TEXT("RadixSort_Upsweep")	,
		SF_Compute
	)

SetRadixSortShaderCompilerEnvironment()

void SetRadixSortShaderCompilerEnvironment

(

FShaderCompilerEnvironment &

OutEnvironment

)

Setup radix sort shader compiler environment.

Parameters

OutEnvironment

- The environment to set.

SortGPUBuffers()

int32 SortGPUBuffers	(	FRHICommandList &	RHICmdList,
		FGPUSortBuffers	SortBuffers,
		int32	BufferIndex,
		uint32	KeyMask,
		int32	Count,
		ERHIFeatureLevel::Type	FeatureLevel
	)

Sort a buffer on the GPU.

Parameters

SortBuffers	- The buffer to sort including required views and a ping- pong location of appropriate size.
BufferIndex	- Index of the buffer containing keys.
KeyMask	- Bitmask indicating which key bits contain useful information.
Count	- How many items in the buffer need to be sorted.

Returns

The index of the buffer containing sorted results.

TestGPUSort()

void TestGPUSort	(	EGPUSortTest	TestToRun,
		ERHIFeatureLevel::Type	FeatureLevel
	)

Test that GPU sorting works.

Parameters

TestToRun

- The test to run.

Variable Documentation

GRadixSortParametersBuffer

TGlobalResource<FRadixSortParametersBuffer> GRadixSortParametersBuffer

The global resource for the radix sort parameters buffer.

GSortOffsetBuffers

TGlobalResource<FSortOffsetBuffers> GSortOffsetBuffers

The global sort offset buffer resources.