ShadowSetup.cpp File Reference

#include "CoreMinimal.h"
#include "Stats/Stats.h"
#include "Misc/MemStack.h"
#include "HAL/IConsoleManager.h"
#include "EngineDefines.h"
#include "RHI.h"
#include "RenderingThread.h"
#include "ConvexVolume.h"
#include "SceneTypes.h"
#include "SceneInterface.h"
#include "SceneVisibility.h"
#include "RendererInterface.h"
#include "PrimitiveViewRelevance.h"
#include "PrimitiveDrawingUtils.h"
#include "ScenePrivateBase.h"
#include "PostProcess/SceneRenderTargets.h"
#include "Math/GenericOctree.h"
#include "LightSceneInfo.h"
#include "ShadowRendering.h"
#include "TextureLayout.h"
#include "SceneRendering.h"
#include "DynamicPrimitiveDrawing.h"
#include "ScenePrivate.h"
#include "RendererModule.h"
#include "CapsuleShadowRendering.h"
#include "Async/ParallelFor.h"
#include "VirtualShadowMaps/VirtualShadowMapCacheManager.h"
#include "VirtualShadowMaps/VirtualShadowMapClipmap.h"
#include "InstanceCulling/InstanceCullingManager.h"
#include "Shadows/ShadowSceneRenderer.h"
#include "RenderCore.h"
#include "StaticMeshBatch.h"
#include "UnrealEngine.h"
#include "CanvasTypes.h"
#include "Shadows/ShadowScene.h"
#include "LineTypes.h"
#include "SceneCulling/SceneCulling.h"
#include "ReadOnlyCVARCache.h"
#include "SceneRenderBuilder.h"

Classes
struct	FBoxEdge
struct	FDrawDebugShadowFrustumOp
struct	FFilteredShadowArrays
class	FShadowMeshCollector
struct	FDynamicShadowsTaskData
struct	FAddSubjectPrimitiveOverflowedIndices
struct	FFinalizeAddSubjectPrimitiveContext
struct	FAddSubjectPrimitiveResult
struct	FAddSubjectPrimitiveOp
struct	FAddSubjectPrimitiveStats
struct	FComparePreshadows
struct	FGatherShadowPrimitivesPacket
struct	FGatherShadowPrimitivesPrepareTask
struct	FLayoutAndAssignedShadows
class	RenderTargetNameSet

Typedefs
typedef TArray< FVector, TInlineAllocator< 8 > >	FBoundingBoxVertexArray
typedef TArray< FBoxEdge, TInlineAllocator< 12 > >	FBoundingBoxEdgeArray
typedef TArray< FAddSubjectPrimitiveOp >	FShadowSubjectPrimitives
typedef TArray< FAddSubjectPrimitiveStats >	FPerShadowGatherStats
using	FProjectedShadowInfoList = TArray< FProjectedShadowInfo *, SceneRenderingAllocator >
typedef TArray< FConvexVolume, TInlineAllocator< 8 > >	FLightViewFrustumConvexHulls

Functions
FAutoConsoleVariableRef	CVarCacheWholeSceneShadows (TEXT("r.Shadow.CacheWholeSceneShadows"), GCacheWholeSceneShadows, TEXT("When enabled, movable point and spot light whole scene shadow depths from static primitives will be cached as an optimization."), ECVF_Scalability|ECVF_RenderThreadSafe)
FAutoConsoleVariableRef	CVarMaxNumPointShadowCacheUpdatePerFrame (TEXT("r.Shadow.MaxNumPointShadowCacheUpdatesPerFrame"), GMaxNumPointShadowCacheUpdatesPerFrame, TEXT("Maximum number of point light shadow cache updates allowed per frame." "Only affect updates caused by resolution change. -1 means no limit."), ECVF_Scalability|ECVF_RenderThreadSafe)
FAutoConsoleVariableRef	CVarMaxNumSpotShadowCacheUpdatePerFrame (TEXT("r.Shadow.MaxNumSpotShadowCacheUpdatesPerFrame"), GMaxNumSpotShadowCacheUpdatesPerFrame, TEXT("Maximum number of spot light shadow cache updates allowed per frame." "Only affect updates caused by resolution change. -1 means no limit."), ECVF_Scalability|ECVF_RenderThreadSafe)
FAutoConsoleVariableRef	CVarWholeSceneShadowCacheMb (TEXT("r.Shadow.WholeSceneShadowCacheMb"), GWholeSceneShadowCacheMb, TEXT("Amount of memory that can be spent caching whole scene shadows. ShadowMap allocations in a single frame can cause this to be exceeded."), ECVF_Scalability|ECVF_RenderThreadSafe)
FAutoConsoleVariableRef	CVarCachedWholeSceneShadowsCastFromMovablePrimitives (TEXT("r.Shadow.CachedShadowsCastFromMovablePrimitives"), GCachedShadowsCastFromMovablePrimitives, TEXT("Disabling this can be used to remove the copy of the cached shadowmap."), ECVF_Scalability|ECVF_RenderThreadSafe)
FAutoConsoleVariableRef	CVarSkipCullingNaniteMeshes (TEXT("r.Shadow.SkipCullingNaniteMeshes"), GSkipCullingNaniteMeshes, TEXT("When enabled, CPU culling will ignore nanite meshes."), ECVF_Scalability|ECVF_RenderThreadSafe)
bool	ShouldUseCachePreshadows ()
FAutoConsoleVariableRef	CVarPreshadowsForceLowestLOD (TEXT("r.Shadow.PreshadowsForceLowestDetailLevel"), GPreshadowsForceLowestLOD, TEXT("When enabled, static meshes render their lowest detail level into preshadow depth maps. Disabled by default as it causes artifacts with poor quality LODs (tree billboard)."), ECVF_Scalability|ECVF_RenderThreadSafe)
uint32	GetNumShadowDynamicMeshElementTasks ()
FAutoConsoleVariableRef	CVarUseOctreeForShadowCulling (TEXT("r.Shadow.UseOctreeForCulling"), GUseOctreeForShadowCulling, TEXT("Whether to use the primitive octree for shadow subject culling. The octree culls large groups of primitives at a time, but introduces cache misses walking the data structure."), ECVF_Scalability|ECVF_RenderThreadSafe)
	CSV_DECLARE_CATEGORY_EXTERN (LightCount)
void	DumpShadowDumpSetup ()
template<typename CacheLambdaType , typename UnCacheLambdaType >
void	TryToCacheShadowMap (const FScene *Scene, int64 CachedShadowMapsSize, int32 &OutNumShadowMaps, EShadowDepthCacheMode *OutCacheModes, uint32 &NumCachesUpdatedThisFrame, CacheLambdaType &&CacheLambda, UnCacheLambdaType &&UnCacheLambda)
float	CalculateShadowFadeAlpha (const float MaxUnclampedResolution, const uint32 ShadowFadeResolution, const uint32 MinShadowResolution)
int32	GetMaxShadowResolution (ERHIFeatureLevel::Type FeatureLevel)
bool	AreAnyViewsStaticSceneOnly (TArrayView< FViewInfo > Views)
UE::Tasks::FTask	GetGatherAndSortLightsPrerequisiteTask (const FDynamicShadowsTaskData *TaskData)
void	BeginShadowGatherDynamicMeshElements (FDynamicShadowsTaskData *TaskData)
TConstArrayView< FProjectedShadowInfo * >	GetProjectedDistanceFieldShadows (const FDynamicShadowsTaskData *TaskData)
bool	ShouldCreateObjectShadowForStationaryLight (const FLightSceneInfo *LightSceneInfo, const FPrimitiveSceneProxy *PrimitiveSceneProxy, bool bInteractionShadowMapped)
void	ComputeWholeSceneShadowCacheModes (const FLightSceneInfo *LightSceneInfo, bool bCubeShadowMap, float RealTime, float ActualDesiredResolution, const FIntPoint &MaxShadowResolution, FScene *Scene, bool bNeedsVirtualShadowMap, FWholeSceneProjectedShadowInitializer &InOutProjectedShadowInitializer, const int64 CachedShadowMapsSize, FIntPoint &InOutShadowMapSize, uint32 &InOutNumPointShadowCachesUpdatedThisFrame, uint32 &InOutNumSpotShadowCachesUpdatedThisFrame, int32 &OutNumShadowMaps, EShadowDepthCacheMode *OutCacheModes)
void	ComputeViewDependentWholeSceneShadowCacheModes (const FLightSceneInfo *LightSceneInfo, float RealTime, FScene *Scene, const FWholeSceneProjectedShadowInitializer &ProjectedShadowInitializer, const int64 CachedShadowMapsSize, const FIntPoint &ShadowMapSize, uint32 &InOutNumCSMCachesUpdatedThisFrame, int32 &OutNumShadowMaps, EShadowDepthCacheMode *OutCacheModes)
void	BuildLightViewFrustumConvexHull (const FVector &LightOrigin, const FConvexVolume &Frustum, FConvexVolume &ConvexHull)
void	BuildLightViewFrustumConvexHulls (const FVector &LightOrigin, const TArray< FViewInfo > &Views, FLightViewFrustumConvexHulls &ConvexHulls)
bool	IntersectsConvexHulls (FLightViewFrustumConvexHulls const &ConvexHulls, FBoxSphereBounds const &Bounds)
TCHAR *const	GetTranslucencyShadowTransmissionName (uint32 Id)

Variables
float	GMinScreenRadiusForShadowCaster = 0.01f
int	GEnableNonNaniteVSM
int32	GCacheWholeSceneShadows = 1
int32	GMaxNumPointShadowCacheUpdatesPerFrame = -1
int32	GMaxNumSpotShadowCacheUpdatesPerFrame = -1
int32	GWholeSceneShadowCacheMb = 150
int32	GCachedShadowsCastFromMovablePrimitives = 1
int32	GSkipCullingNaniteMeshes = 1
int32	GPreshadowsForceLowestLOD = 0
int32	GParallelInitDynamicShadows = 1
int32	GNumShadowDynamicMeshElementTasks = 4
int32	GUseOctreeForShadowCulling = 1
TAutoConsoleVariable< int32 >	CVarVsmUseFarShadowRules (TEXT("r.Shadow.Virtual.UseFarShadowCulling"), 1, TEXT("Switch between implementing the far shadow culling logic for VSMs."), ECVF_RenderThreadSafe)
bool	GDumpShadowSetup = false
FAutoConsoleCommand	CmdDumpShadowDumpSetup (TEXT("r.DumpShadows"), TEXT("Dump shadow setup (for developer only, only for non shiping build)"), FConsoleCommandDelegate::CreateStatic(DumpShadowDumpSetup))
FAutoConsoleVariableRef	CVarComputeShadowFadeUsingResolutionScale (TEXT("r.Shadow.DoesFadeUseResolutionScale"), GDoesShadowFadeUseResolutionScale, TEXT("When enabled (default), the shadow resolution scale for the individual light feeds into the fade out calculation, increasing the control of shadow fade out.\n" " Setting the cvar to 0 restores the behavior to pre UE 5.6."), ECVF_RenderThreadSafe)
FAutoConsoleTaskPriority	CPrio_GatherShadowPrimitives (TEXT("TaskGraph.TaskPriorities.GatherShadowPrimitives"), TEXT("Task and thread priority for GatherShadowPrimitives tasks."), ENamedThreads::HighThreadPriority, ENamedThreads::NormalTaskPriority, ENamedThreads::HighTaskPriority)

Typedef Documentation

FBoundingBoxEdgeArray

typedef TArray<FBoxEdge,TInlineAllocator<12> > FBoundingBoxEdgeArray

FBoundingBoxVertexArray

typedef TArray<FVector,TInlineAllocator<8> > FBoundingBoxVertexArray

FLightViewFrustumConvexHulls

typedef TArray<FConvexVolume, TInlineAllocator<8> > FLightViewFrustumConvexHulls

FPerShadowGatherStats

typedef TArray<FAddSubjectPrimitiveStats> FPerShadowGatherStats

FProjectedShadowInfoList

using FProjectedShadowInfoList = TArray<FProjectedShadowInfo*, SceneRenderingAllocator>

FShadowSubjectPrimitives

typedef TArray<FAddSubjectPrimitiveOp> FShadowSubjectPrimitives

Function Documentation

AreAnyViewsStaticSceneOnly()

bool AreAnyViewsStaticSceneOnly ( TArrayView< FViewInfo >  Views )

inline

BeginShadowGatherDynamicMeshElements()

void BeginShadowGatherDynamicMeshElements

(

FDynamicShadowsTaskData *

TaskData

)

Triggers shadow gather dynamic mesh elements task graph to start processing.

BuildLightViewFrustumConvexHull()

void BuildLightViewFrustumConvexHull	(	const FVector &	LightOrigin,
		const FConvexVolume &	Frustum,
		FConvexVolume &	ConvexHull
	)

BuildLightViewFrustumConvexHulls()

void BuildLightViewFrustumConvexHulls	(	const FVector &	LightOrigin,
		const TArray< FViewInfo > &	Views,
		FLightViewFrustumConvexHulls &	ConvexHulls
	)

CalculateShadowFadeAlpha()

float CalculateShadowFadeAlpha	(	const float	MaxUnclampedResolution,
		const uint32	ShadowFadeResolution,
		const uint32	MinShadowResolution
	)

Helper function to determine fade alpha value for shadows based on resolution. In the below ASCII art (1) is the MinShadowResolution and (2) is the ShadowFadeResolution. Alpha will be 0 below the min resolution and 1 above the fade resolution. In between it is going to be an exponential curve with the values between (1) and (2) being normalized in the 0..1 range.

| /----— | / |/ 1--—2----—

Parameters

MaxUnclampedResolution	Requested resolution, unclamped so it can be below min
ShadowFadeResolution	Resolution at which fade begins
MinShadowResolution	Minimum resolution of shadow

Returns

fade value between 0 and 1

ComputeViewDependentWholeSceneShadowCacheModes()

void ComputeViewDependentWholeSceneShadowCacheModes	(	const FLightSceneInfo *	LightSceneInfo,
		float	RealTime,
		FScene *	Scene,
		const FWholeSceneProjectedShadowInitializer &	ProjectedShadowInitializer,
		const int64	CachedShadowMapsSize,
		const FIntPoint &	ShadowMapSize,
		uint32 &	InOutNumCSMCachesUpdatedThisFrame,
		int32 &	OutNumShadowMaps,
		EShadowDepthCacheMode *	OutCacheModes
	)

ComputeWholeSceneShadowCacheModes()

void ComputeWholeSceneShadowCacheModes	(	const FLightSceneInfo *	LightSceneInfo,
		bool	bCubeShadowMap,
		float	RealTime,
		float	ActualDesiredResolution,
		const FIntPoint &	MaxShadowResolution,
		FScene *	Scene,
		bool	bNeedsVirtualShadowMap,
		FWholeSceneProjectedShadowInitializer &	InOutProjectedShadowInitializer,
		const int64	CachedShadowMapsSize,
		FIntPoint &	InOutShadowMapSize,
		uint32 &	InOutNumPointShadowCachesUpdatedThisFrame,
		uint32 &	InOutNumSpotShadowCachesUpdatedThisFrame,
		int32 &	OutNumShadowMaps,
		EShadowDepthCacheMode *	OutCacheModes
	)

CSV_DECLARE_CATEGORY_EXTERN()

CSV_DECLARE_CATEGORY_EXTERN

(

LightCount

)

CVarCachedWholeSceneShadowsCastFromMovablePrimitives()

FAutoConsoleVariableRef CVarCachedWholeSceneShadowsCastFromMovablePrimitives	(	TEXT("r.Shadow.CachedShadowsCastFromMovablePrimitives")	,
		GCachedShadowsCastFromMovablePrimitives	,
		TEXT("Disabling this can be used to remove the copy of the cached shadowmap.")	,
		ECVF_Scalability|	ECVF_RenderThreadSafe
	)

CVarCacheWholeSceneShadows()

FAutoConsoleVariableRef CVarCacheWholeSceneShadows	(	TEXT("r.Shadow.CacheWholeSceneShadows")	,
		GCacheWholeSceneShadows	,
		TEXT("When enabled, movable point and spot light whole scene shadow depths from static primitives will be cached as an optimization.")	,
		ECVF_Scalability|	ECVF_RenderThreadSafe
	)

CVarMaxNumPointShadowCacheUpdatePerFrame()

FAutoConsoleVariableRef CVarMaxNumPointShadowCacheUpdatePerFrame	(	TEXT("r.Shadow.MaxNumPointShadowCacheUpdatesPerFrame")	,
		GMaxNumPointShadowCacheUpdatesPerFrame	,
		TEXT("Maximum number of point light shadow cache updates allowed per frame." "Only affect updates caused by resolution change. -1 means no limit.")	,
		ECVF_Scalability|	ECVF_RenderThreadSafe
	)

CVarMaxNumSpotShadowCacheUpdatePerFrame()

FAutoConsoleVariableRef CVarMaxNumSpotShadowCacheUpdatePerFrame	(	TEXT("r.Shadow.MaxNumSpotShadowCacheUpdatesPerFrame")	,
		GMaxNumSpotShadowCacheUpdatesPerFrame	,
		TEXT("Maximum number of spot light shadow cache updates allowed per frame." "Only affect updates caused by resolution change. -1 means no limit.")	,
		ECVF_Scalability|	ECVF_RenderThreadSafe
	)

CVarPreshadowsForceLowestLOD()

FAutoConsoleVariableRef CVarPreshadowsForceLowestLOD	(	TEXT("r.Shadow.PreshadowsForceLowestDetailLevel")	,
		GPreshadowsForceLowestLOD	,
		TEXT("When enabled, static meshes render their lowest detail level into preshadow depth maps. Disabled by default as it causes artifacts with poor quality LODs (tree billboard).")	,
		ECVF_Scalability|	ECVF_RenderThreadSafe
	)

CVarSkipCullingNaniteMeshes()

FAutoConsoleVariableRef CVarSkipCullingNaniteMeshes	(	TEXT("r.Shadow.SkipCullingNaniteMeshes")	,
		GSkipCullingNaniteMeshes	,
		TEXT("When enabled, CPU culling will ignore nanite meshes.")	,
		ECVF_Scalability|	ECVF_RenderThreadSafe
	)

CVarUseOctreeForShadowCulling()

FAutoConsoleVariableRef CVarUseOctreeForShadowCulling	(	TEXT("r.Shadow.UseOctreeForCulling")	,
		GUseOctreeForShadowCulling	,
		TEXT("Whether to use the primitive octree for shadow subject culling. The octree culls large groups of primitives at a time, but introduces cache misses walking the data structure.")	,
		ECVF_Scalability|	ECVF_RenderThreadSafe
	)

CVarWholeSceneShadowCacheMb()

FAutoConsoleVariableRef CVarWholeSceneShadowCacheMb	(	TEXT("r.Shadow.WholeSceneShadowCacheMb")	,
		GWholeSceneShadowCacheMb	,
		TEXT("Amount of memory that can be spent caching whole scene shadows. ShadowMap allocations in a single frame can cause this to be exceeded.")	,
		ECVF_Scalability|	ECVF_RenderThreadSafe
	)

DumpShadowDumpSetup()

void DumpShadowDumpSetup

(

)

GetGatherAndSortLightsPrerequisiteTask()

UE::Tasks::FTask GetGatherAndSortLightsPrerequisiteTask

(

const FDynamicShadowsTaskData *

TaskData

)

GetMaxShadowResolution()

int32 GetMaxShadowResolution

(

ERHIFeatureLevel::Type

FeatureLevel

)

GetNumShadowDynamicMeshElementTasks()

uint32 GetNumShadowDynamicMeshElementTasks

(

)

GetProjectedDistanceFieldShadows()

TConstArrayView< FProjectedShadowInfo * > GetProjectedDistanceFieldShadows

(

const FDynamicShadowsTaskData *

TaskData

)

Returns the array of shadows with distance fields. Call only after finishing shadow initialization.

GetTranslucencyShadowTransmissionName()

TCHAR *const GetTranslucencyShadowTransmissionName

(

uint32

Id

)

IntersectsConvexHulls()

bool IntersectsConvexHulls	(	FLightViewFrustumConvexHulls const &	ConvexHulls,
		FBoxSphereBounds const &	Bounds
	)

ShouldCreateObjectShadowForStationaryLight()

bool ShouldCreateObjectShadowForStationaryLight	(	const FLightSceneInfo *	LightSceneInfo,
		const FPrimitiveSceneProxy *	PrimitiveSceneProxy,
		bool	bInteractionShadowMapped
	)

ShouldUseCachePreshadows()

bool ShouldUseCachePreshadows

(

)

TryToCacheShadowMap()

template<typename CacheLambdaType , typename UnCacheLambdaType >

void TryToCacheShadowMap	(	const FScene *	Scene,
		int64	CachedShadowMapsSize,
		int32 &	OutNumShadowMaps,
		EShadowDepthCacheMode *	OutCacheModes,
		uint32 &	NumCachesUpdatedThisFrame,
		CacheLambdaType &&	CacheLambda,
		UnCacheLambdaType &&	UnCacheLambda
	)

Helper function to maintain the common login of caching the whole scene shadow and be able to handle the specific-purpose through the CacheLambda and UnCacheLambda

Variable Documentation

CmdDumpShadowDumpSetup

FAutoConsoleCommand CmdDumpShadowDumpSetup(TEXT("r.DumpShadows"), TEXT("Dump shadow setup (for developer only, only for non shiping build)"), FConsoleCommandDelegate::CreateStatic(DumpShadowDumpSetup))	(	TEXT("r.DumpShadows")	,
		TEXT("Dump shadow setup (for developer only, only for non shiping build)")	,
		FConsoleCommandDelegate::CreateStatic(DumpShadowDumpSetup)
	)

CPrio_GatherShadowPrimitives

FAutoConsoleTaskPriority CPrio_GatherShadowPrimitives(TEXT("TaskGraph.TaskPriorities.GatherShadowPrimitives"), TEXT("Task and thread priority for GatherShadowPrimitives tasks."), ENamedThreads::HighThreadPriority, ENamedThreads::NormalTaskPriority, ENamedThreads::HighTaskPriority)	(	TEXT("TaskGraph.TaskPriorities.GatherShadowPrimitives")	,
		TEXT("Task and thread priority for GatherShadowPrimitives tasks.")	,
		ENamedThreads::HighThreadPriority	,
		ENamedThreads::NormalTaskPriority	,
		ENamedThreads::HighTaskPriority
	)

CVarComputeShadowFadeUsingResolutionScale

FAutoConsoleVariableRef CVarComputeShadowFadeUsingResolutionScale(TEXT("r.Shadow.DoesFadeUseResolutionScale"), GDoesShadowFadeUseResolutionScale, TEXT("When enabled (default), the shadow resolution scale for the individual light feeds into the fade out calculation, increasing the control of shadow fade out.\n" " Setting the cvar to 0 restores the behavior to pre UE 5.6."), ECVF_RenderThreadSafe)	(	TEXT("r.Shadow.DoesFadeUseResolutionScale")	,
		GDoesShadowFadeUseResolutionScale	,
		TEXT("When enabled (default), the shadow resolution scale for the individual light feeds into the fade out calculation, increasing the control of shadow fade out.\n" " Setting the cvar to 0 restores the behavior to pre UE 5.6.")	,
		ECVF_RenderThreadSafe
	)

CVarVsmUseFarShadowRules

TAutoConsoleVariable< int32 > CVarVsmUseFarShadowRules(TEXT("r.Shadow.Virtual.UseFarShadowCulling"), 1, TEXT("Switch between implementing the far shadow culling logic for VSMs."), ECVF_RenderThreadSafe)	(	TEXT("r.Shadow.Virtual.UseFarShadowCulling")	,
		1	,
		TEXT("Switch between implementing the far shadow culling logic for VSMs.")	,
		ECVF_RenderThreadSafe
	)

GCachedShadowsCastFromMovablePrimitives

int32 GCachedShadowsCastFromMovablePrimitives = 1

GCacheWholeSceneShadows

int32 GCacheWholeSceneShadows = 1

GDumpShadowSetup

bool GDumpShadowSetup = false

GEnableNonNaniteVSM

int GEnableNonNaniteVSM

extern

GMaxNumPointShadowCacheUpdatesPerFrame

int32 GMaxNumPointShadowCacheUpdatesPerFrame = -1

GMaxNumSpotShadowCacheUpdatesPerFrame

int32 GMaxNumSpotShadowCacheUpdatesPerFrame = -1

GMinScreenRadiusForShadowCaster

float GMinScreenRadiusForShadowCaster = 0.01f

GNumShadowDynamicMeshElementTasks

int32 GNumShadowDynamicMeshElementTasks = 4

GParallelInitDynamicShadows

int32 GParallelInitDynamicShadows = 1

GPreshadowsForceLowestLOD

int32 GPreshadowsForceLowestLOD = 0

GSkipCullingNaniteMeshes

int32 GSkipCullingNaniteMeshes = 1

GUseOctreeForShadowCulling

int32 GUseOctreeForShadowCulling = 1

GWholeSceneShadowCacheMb

int32 GWholeSceneShadowCacheMb = 150