LightGridInjection.cpp File Reference

#include "CoreMinimal.h"
#include "Stats/Stats.h"
#include "HAL/IConsoleManager.h"
#include "RHI.h"
#include "UniformBuffer.h"
#include "ShaderParameters.h"
#include "RendererInterface.h"
#include "EngineDefines.h"
#include "PrimitiveSceneProxy.h"
#include "Shader.h"
#include "SceneUtils.h"
#include "PostProcess/SceneRenderTargets.h"
#include "LightSceneInfo.h"
#include "RectLightSceneProxy.h"
#include "GlobalShader.h"
#include "SceneRendering.h"
#include "DeferredShadingRenderer.h"
#include "BasePassRendering.h"
#include "RendererModule.h"
#include "ScenePrivate.h"
#include "ClearQuad.h"
#include "VolumetricFog.h"
#include "VolumetricCloudRendering.h"
#include "Components/LightComponent.h"
#include "Engine/MapBuildDataRegistry.h"
#include "PixelShaderUtils.h"
#include "ShaderPrint.h"
#include "ShaderPrintParameters.h"
#include "RenderUtils.h"
#include "MegaLights/MegaLights.h"
#include "LightGridDefinitions.h"
#include "LightViewData.h"

Classes
class	FLightGridInjectionCS
struct	FLightGrid
class	FDebugLightGridPS
class	FLightGridFeedbackStatusCS
class	FLightGridFeedbackStatus

Typedefs
typedef uint16	FLightIndexType
typedef uint32	FLightIndexType32

Enumerations
enum class	ELightBufferMode { VisibleLocalLights = 0 , VisibleLights = 1 , VisibleLightsStableIndices = 2 }

Functions
FAutoConsoleVariableRef	CVarLightGridPixelSize (TEXT("r.Forward.LightGridPixelSize"), GLightGridPixelSize, TEXT("Size of a cell in the light grid, in pixels."), ECVF_Scalability|ECVF_RenderThreadSafe)
FAutoConsoleVariableRef	CVarLightGridSizeZ (TEXT("r.Forward.LightGridSizeZ"), GLightGridSizeZ, TEXT("Number of Z slices in the light grid."), ECVF_Scalability|ECVF_RenderThreadSafe)
FAutoConsoleVariableRef	CVarLightGridHZBCull (TEXT("r.Forward.LightGridHZBCull"), GLightGridHZBCull, TEXT("Whether to use HZB culling to skip occluded grid cells."), ECVF_Scalability|ECVF_RenderThreadSafe)
FAutoConsoleVariableRef	CVarMaxCulledLightsPerCell (TEXT("r.Forward.MaxCulledLightsPerCell"), GMaxCulledLightsPerCell, TEXT("Controls how much memory is allocated for each cell for light culling. When r.Forward.LightLinkedListCulling is enabled, this is used to compute a global max instead of a per-cell limit on culled lights."), ECVF_Scalability|ECVF_RenderThreadSafe)
FAutoConsoleVariableRef	CVarLightLinkedListCulling (TEXT("r.Forward.LightLinkedListCulling"), GLightLinkedListCulling, TEXT("Uses a reverse linked list to store culled lights, removing the fixed limit on how many lights can affect a cell - it becomes a global limit instead."), ECVF_Scalability|ECVF_RenderThreadSafe)
	DECLARE_GPU_STAT (LightGrid)
void	LightGridFeedbackStatus (FRDGBuilder &GraphBuilder, FViewInfo &View, FRDGBufferRef CulledLightDataAllocatorBuffer, uint32 NumCulledLightDataEntries, FRDGBufferRef CulledLightLinkAllocatorBuffer, uint32 NumCulledLightLinks, bool bUseAsyncCompute)
bool	ShouldVisualizeLightGrid (EShaderPlatform InShaderPlatform)
bool	LightGridUses16BitBuffers (EShaderPlatform Platform)
void	SetupDummyForwardLightUniformParameters (FRDGBuilder &GraphBuilder, FForwardLightUniformParameters &ForwardLightUniformParameters, EShaderPlatform ShaderPlatform)
TRDGUniformBufferRef< FForwardLightUniformParameters >	CreateDummyForwardLightUniformBuffer (FRDGBuilder &GraphBuilder, EShaderPlatform ShaderPlatform)
void	SetDummyForwardLightUniformBufferOnViews (FRDGBuilder &GraphBuilder, EShaderPlatform ShaderPlatform, TArray< FViewInfo > &Views)
	IMPLEMENT_GLOBAL_SHADER_PARAMETER_STRUCT (FForwardLightUniformParameters, "ForwardLightStruct")
	IMPLEMENT_GLOBAL_SHADER (FLightGridInjectionCS, "/Engine/Private/LightGridInjection.usf", "LightGridInjectionCS", SF_Compute)
FORCEINLINE float	GetTanRadAngleOrZero (float coneAngle)
FVector	GetLightGridZParams (float NearPlane, float FarPlane)
uint32	PackRG16 (float In0, float In1)
FLightGrid	LightGridInjection (FRDGBuilder &GraphBuilder, FViewInfo &View, FIntVector GridSize, uint32 LightGridPixelSizeShift, uint32 ZSliceScale, uint32 MaxNumCells, FVector3f ZParams, uint32 LightGridCullMarginXY, uint32 LightGridCullMarginZ, FVector3f LightGridCullMarginZParams, uint32 LightGridCullMaxZ, uint32 NumLocalLights, uint32 NumReflectionCaptures, uint32 MegaLightsSupportedStartIndex, bool bUse16BitBuffers, bool bRefineRectLightBounds, FRDGBufferSRVRef LightViewSpacePositionAndRadiusSRV, FRDGBufferSRVRef LightViewSpaceDirAndPreprocAngleSRV, FRDGBufferSRVRef LightViewSpaceRectPlanesSRV, FRDGBufferSRVRef IndirectionIndicesSRV, bool bThreadGroupPerCell, bool bThreadGroupSize32, FRDGBufferSRVRef ParentNumCulledLightsGridSRV, FRDGBufferSRVRef ParentCulledLightDataGridSRV, uint32 ParentGridSizeFactor)
	IMPLEMENT_GLOBAL_SHADER (FDebugLightGridPS, "/Engine/Private/LightGridInjection.usf", "DebugLightGridPS", SF_Pixel)
FScreenPassTexture	AddVisualizeLightGridPass (FRDGBuilder &GraphBuilder, const FViewInfo &View, FScreenPassTexture ScreenPassSceneColor, FScreenPassTexture SceneDepthTexture)
	IMPLEMENT_GLOBAL_SHADER (FLightGridFeedbackStatusCS, "/Engine/Private/LightGridInjection.usf", "FeedbackStatusCS", SF_Compute)

Variables
int32	GLightGridPixelSize = 64
int32	GLightGridSizeZ = 32
int32	GForwardLightGridDebug = 0
FAutoConsoleVariableRef	CVarLightGridDebug (TEXT("r.Forward.LightGridDebug"), GForwardLightGridDebug, TEXT(" 3: on - showing max light count per tile accoung for each slice and the last one \n"), ECVF_RenderThreadSafe)
int32	GForwardLightGridDebugMaxThreshold = 8
FAutoConsoleVariableRef	CVarLightGridDebugMaxThreshold (TEXT("r.Forward.LightGridDebug.MaxThreshold"), GForwardLightGridDebugMaxThreshold, TEXT("Maximum light threshold for heat map visualization. (default = 8)\n"), ECVF_RenderThreadSafe)
int32	GLightGridHZBCull = 1
int32	GLightGridRefineRectLightBounds = 1
FAutoConsoleVariableRef	CVarLightGridRefineRectLightBounds (TEXT("r.Forward.LightGridDebug.RectLightBounds"), GLightGridRefineRectLightBounds, TEXT("Whether to refine rect light bounds (should only be disabled for debugging purposes)."), ECVF_RenderThreadSafe)
int32	GMaxCulledLightsPerCell = 32
int32	GLightLinkedListCulling = 1
int32	GLightCullingQuality = 1
FAutoConsoleVariableRef	CVarLightCullingQuality (TEXT("r.LightCulling.Quality"), GLightCullingQuality, TEXT(" 1: on (default)\n"), ECVF_RenderThreadSafe)
float	GLightCullingMaxDistanceOverrideKilometers = -1.0f
FAutoConsoleVariableRef	CVarLightCullingMaxDistanceOverride (TEXT("r.LightCulling.MaxDistanceOverrideKilometers"), GLightCullingMaxDistanceOverrideKilometers, TEXT(" >0: the far distance in kilometers.\n"), ECVF_RenderThreadSafe)
int32	NumCulledLightsGridStride = 2
int32	NumCulledGridPrimitiveTypes = 2
int32	LightLinkStride = 2
TGlobalResource< FLightGridFeedbackStatus >	GLightGridFeedbackStatus

Typedef Documentation

FLightIndexType

typedef uint16 FLightIndexType

FLightIndexType32

typedef uint32 FLightIndexType32

Enumeration Type Documentation

ELightBufferMode

enum class ELightBufferMode

strong

Enumerator
VisibleLocalLights
VisibleLights
VisibleLightsStableIndices

Function Documentation

AddVisualizeLightGridPass()

FScreenPassTexture AddVisualizeLightGridPass	(	FRDGBuilder &	GraphBuilder,
		const FViewInfo &	View,
		FScreenPassTexture	ScreenPassSceneColor,
		FScreenPassTexture	SceneDepthTexture
	)

CreateDummyForwardLightUniformBuffer()

TRDGUniformBufferRef< FForwardLightUniformParameters > CreateDummyForwardLightUniformBuffer	(	FRDGBuilder &	GraphBuilder,
		EShaderPlatform	ShaderPlatform
	)

CVarLightGridHZBCull()

FAutoConsoleVariableRef CVarLightGridHZBCull	(	TEXT("r.Forward.LightGridHZBCull")	,
		GLightGridHZBCull	,
		TEXT("Whether to use HZB culling to skip occluded grid cells.")	,
		ECVF_Scalability|	ECVF_RenderThreadSafe
	)

CVarLightGridPixelSize()

FAutoConsoleVariableRef CVarLightGridPixelSize	(	TEXT("r.Forward.LightGridPixelSize")	,
		GLightGridPixelSize	,
		TEXT("Size of a cell in the light grid, in pixels.")	,
		ECVF_Scalability|	ECVF_RenderThreadSafe
	)

CVarLightGridSizeZ()

FAutoConsoleVariableRef CVarLightGridSizeZ	(	TEXT("r.Forward.LightGridSizeZ")	,
		GLightGridSizeZ	,
		TEXT("Number of Z slices in the light grid.")	,
		ECVF_Scalability|	ECVF_RenderThreadSafe
	)

CVarLightLinkedListCulling()

FAutoConsoleVariableRef CVarLightLinkedListCulling	(	TEXT("r.Forward.LightLinkedListCulling")	,
		GLightLinkedListCulling	,
		TEXT("Uses a reverse linked list to store culled lights, removing the fixed limit on how many lights can affect a cell - it becomes a global limit instead.")	,
		ECVF_Scalability|	ECVF_RenderThreadSafe
	)

CVarMaxCulledLightsPerCell()

FAutoConsoleVariableRef CVarMaxCulledLightsPerCell	(	TEXT("r.Forward.MaxCulledLightsPerCell")	,
		GMaxCulledLightsPerCell	,
		TEXT("Controls how much memory is allocated for each cell for light culling. When r.Forward.LightLinkedListCulling is enabled, this is used to compute a global max instead of a per-cell limit on culled lights.")	,
		ECVF_Scalability|	ECVF_RenderThreadSafe
	)

DECLARE_GPU_STAT()

DECLARE_GPU_STAT

(

LightGrid

)

GetLightGridZParams()

FVector GetLightGridZParams	(	float	NearPlane,
		float	FarPlane
	)

GetTanRadAngleOrZero()

FORCEINLINE float GetTanRadAngleOrZero

(

float

coneAngle

)

IMPLEMENT_GLOBAL_SHADER() [1/3]

IMPLEMENT_GLOBAL_SHADER	(	FDebugLightGridPS	,
		"/Engine/Private/LightGridInjection.usf"	,
		"DebugLightGridPS"	,
		SF_Pixel
	)

IMPLEMENT_GLOBAL_SHADER() [2/3]

IMPLEMENT_GLOBAL_SHADER	(	FLightGridFeedbackStatusCS	,
		"/Engine/Private/LightGridInjection.usf"	,
		"FeedbackStatusCS"	,
		SF_Compute
	)

IMPLEMENT_GLOBAL_SHADER() [3/3]

IMPLEMENT_GLOBAL_SHADER	(	FLightGridInjectionCS	,
		"/Engine/Private/LightGridInjection.usf"	,
		"LightGridInjectionCS"	,
		SF_Compute
	)

IMPLEMENT_GLOBAL_SHADER_PARAMETER_STRUCT()

IMPLEMENT_GLOBAL_SHADER_PARAMETER_STRUCT	(	FForwardLightUniformParameters	,
		"ForwardLightStruct"
	)

LightGridFeedbackStatus()

void LightGridFeedbackStatus	(	FRDGBuilder &	GraphBuilder,
		FViewInfo &	View,
		FRDGBufferRef	CulledLightDataAllocatorBuffer,
		uint32	NumCulledLightDataEntries,
		FRDGBufferRef	CulledLightLinkAllocatorBuffer,
		uint32	NumCulledLightLinks,
		bool	bUseAsyncCompute
	)

LightGridInjection()

FLightGrid LightGridInjection	(	FRDGBuilder &	GraphBuilder,
		FViewInfo &	View,
		FIntVector	GridSize,
		uint32	LightGridPixelSizeShift,
		uint32	ZSliceScale,
		uint32	MaxNumCells,
		FVector3f	ZParams,
		uint32	LightGridCullMarginXY,
		uint32	LightGridCullMarginZ,
		FVector3f	LightGridCullMarginZParams,
		uint32	LightGridCullMaxZ,
		uint32	NumLocalLights,
		uint32	NumReflectionCaptures,
		uint32	MegaLightsSupportedStartIndex,
		bool	bUse16BitBuffers,
		bool	bRefineRectLightBounds,
		FRDGBufferSRVRef	LightViewSpacePositionAndRadiusSRV,
		FRDGBufferSRVRef	LightViewSpaceDirAndPreprocAngleSRV,
		FRDGBufferSRVRef	LightViewSpaceRectPlanesSRV,
		FRDGBufferSRVRef	IndirectionIndicesSRV,
		bool	bThreadGroupPerCell,
		bool	bThreadGroupSize32,
		FRDGBufferSRVRef	ParentNumCulledLightsGridSRV,
		FRDGBufferSRVRef	ParentCulledLightDataGridSRV,
		uint32	ParentGridSizeFactor
	)

LightGridUses16BitBuffers()

bool LightGridUses16BitBuffers

(

EShaderPlatform

Platform

)

PackRG16()

uint32 PackRG16	(	float	In0,
		float	In1
	)

SetDummyForwardLightUniformBufferOnViews()

void SetDummyForwardLightUniformBufferOnViews	(	FRDGBuilder &	GraphBuilder,
		EShaderPlatform	ShaderPlatform,
		TArray< FViewInfo > &	Views
	)

SetupDummyForwardLightUniformParameters()

void SetupDummyForwardLightUniformParameters	(	FRDGBuilder &	GraphBuilder,
		FForwardLightUniformParameters &	ForwardLightUniformParameters,
		EShaderPlatform	ShaderPlatform
	)

ShouldVisualizeLightGrid()

bool ShouldVisualizeLightGrid

(

EShaderPlatform

InShaderPlatform

)

Variable Documentation

CVarLightCullingMaxDistanceOverride

FAutoConsoleVariableRef CVarLightCullingMaxDistanceOverride(TEXT("r.LightCulling.MaxDistanceOverrideKilometers"), GLightCullingMaxDistanceOverrideKilometers, TEXT(" >0: the far distance in kilometers.\n"), ECVF_RenderThreadSafe)	(	TEXT("r.LightCulling.MaxDistanceOverrideKilometers")	,
		GLightCullingMaxDistanceOverrideKilometers	,
		TEXT(" >0: the far distance in kilometers.\n")	,
		ECVF_RenderThreadSafe
	)

CVarLightCullingQuality

FAutoConsoleVariableRef CVarLightCullingQuality(TEXT("r.LightCulling.Quality"), GLightCullingQuality, TEXT(" 1: on (default)\n"), ECVF_RenderThreadSafe)	(	TEXT("r.LightCulling.Quality")	,
		GLightCullingQuality	,
		TEXT(" 1: on (default)\n")	,
		ECVF_RenderThreadSafe
	)

CVarLightGridDebug

FAutoConsoleVariableRef CVarLightGridDebug(TEXT("r.Forward.LightGridDebug"), GForwardLightGridDebug, TEXT(" 3: on - showing max light count per tile accoung for each slice and the last one \n"), ECVF_RenderThreadSafe)	(	TEXT("r.Forward.LightGridDebug")	,
		GForwardLightGridDebug	,
		TEXT(" 3: on - showing max light count per tile accoung for each slice and the last one \n")	,
		ECVF_RenderThreadSafe
	)

CVarLightGridDebugMaxThreshold

FAutoConsoleVariableRef CVarLightGridDebugMaxThreshold(TEXT("r.Forward.LightGridDebug.MaxThreshold"), GForwardLightGridDebugMaxThreshold, TEXT("Maximum light threshold for heat map visualization. (default = 8)\n"), ECVF_RenderThreadSafe)	(	TEXT("r.Forward.LightGridDebug.MaxThreshold")	,
		GForwardLightGridDebugMaxThreshold	,
		TEXT("Maximum light threshold for heat map visualization. (default = 8)\n")	,
		ECVF_RenderThreadSafe
	)

CVarLightGridRefineRectLightBounds

FAutoConsoleVariableRef CVarLightGridRefineRectLightBounds(TEXT("r.Forward.LightGridDebug.RectLightBounds"), GLightGridRefineRectLightBounds, TEXT("Whether to refine rect light bounds (should only be disabled for debugging purposes)."), ECVF_RenderThreadSafe)	(	TEXT("r.Forward.LightGridDebug.RectLightBounds")	,
		GLightGridRefineRectLightBounds	,
		TEXT("Whether to refine rect light bounds (should only be disabled for debugging purposes).")	,
		ECVF_RenderThreadSafe
	)

GForwardLightGridDebug

int32 GForwardLightGridDebug = 0

GForwardLightGridDebugMaxThreshold

int32 GForwardLightGridDebugMaxThreshold = 8

GLightCullingMaxDistanceOverrideKilometers

float GLightCullingMaxDistanceOverrideKilometers = -1.0f

GLightCullingQuality

int32 GLightCullingQuality = 1

GLightGridFeedbackStatus

TGlobalResource<FLightGridFeedbackStatus> GLightGridFeedbackStatus

GLightGridHZBCull

int32 GLightGridHZBCull = 1

GLightGridPixelSize

int32 GLightGridPixelSize = 64

GLightGridRefineRectLightBounds

int32 GLightGridRefineRectLightBounds = 1

GLightGridSizeZ

int32 GLightGridSizeZ = 32

GLightLinkedListCulling

int32 GLightLinkedListCulling = 1

GMaxCulledLightsPerCell

int32 GMaxCulledLightsPerCell = 32

LightLinkStride

int32 LightLinkStride = 2

NumCulledGridPrimitiveTypes

int32 NumCulledGridPrimitiveTypes = 2

NumCulledLightsGridStride

int32 NumCulledLightsGridStride = 2