// Copyright 1998-2017 Epic Games, Inc. All Rights Reserved.

/*=============================================================================
	Scene.cpp: Scene manager implementation.
=============================================================================*/

#include "CoreMinimal.h"
#include "HAL/ThreadSafeCounter.h"
#include "Stats/Stats.h"
#include "HAL/IConsoleManager.h"
#include "Misc/App.h"
#include "UObject/UObjectIterator.h"
#include "Misc/PackageName.h"
#include "EngineDefines.h"
#include "EngineGlobals.h"
#include "Components/ActorComponent.h"
#include "RHI.h"
#include "RenderingThread.h"
#include "RenderResource.h"
#include "UniformBuffer.h"
#include "SceneTypes.h"
#include "SceneInterface.h"
#include "Components/PrimitiveComponent.h"
#include "MaterialShared.h"
#include "SceneManagement.h"
#include "PrecomputedLightVolume.h"
#include "Components/LightComponent.h"
#include "GameFramework/WorldSettings.h"
#include "Components/DecalComponent.h"
#include "Components/ReflectionCaptureComponent.h"
#include "ScenePrivateBase.h"
#include "SceneCore.h"
#include "PrimitiveSceneInfo.h"
#include "LightSceneInfo.h"
#include "StaticMeshDrawList.h"
#include "LightMapRendering.h"
#include "AtmosphereRendering.h"
#include "BasePassRendering.h"
#include "MobileBasePassRendering.h"
#include "LightPropagationVolume.h"
#include "ScenePrivate.h"
#include "RendererModule.h"
#include "StaticMeshResources.h"
#include "ParameterCollection.h"
#include "DistanceFieldAmbientOcclusion.h"
#include "EngineModule.h"
#include "FXSystem.h"
#include "DistanceFieldLightingShared.h"
#include "SpeedTreeWind.h"
#include "Components/WindDirectionalSourceComponent.h"
#include "PlanarReflectionSceneProxy.h"
#include "Engine/StaticMesh.h"
#include "GPUSkinCache.h"

// Enable this define to do slow checks for components being added to the wrong
// world's scene, when using PIE. This can happen if a PIE component is reattached
// while GWorld is the editor world, for example.
#define CHECK_FOR_PIE_PRIMITIVE_ATTACH_SCENE_MISMATCH	0


IMPLEMENT_UNIFORM_BUFFER_STRUCT(FDistanceCullFadeUniformShaderParameters,TEXT("PrimitiveFade"));

/** Global primitive uniform buffer resource containing faded in */
TGlobalResource< FGlobalDistanceCullFadeUniformBuffer > GDistanceCullFadedInUniformBuffer;

SIZE_T FStaticMeshDrawListBase::TotalBytesUsed = 0;

static FThreadSafeCounter FSceneViewState_UniqueID;

/**
 * Holds the info to update SpeedTree wind per unique tree object in the scene, instead of per instance
 */
struct FSpeedTreeWindComputation
{
	explicit FSpeedTreeWindComputation() :
		ReferenceCount(1)
	{
	}

	/** SpeedTree wind object */
	FSpeedTreeWind Wind;

	/** Uniform buffer shared between trees of the same type. */
	TUniformBuffer<FSpeedTreeUniformParameters> UniformBuffer;

	int32 ReferenceCount;
};


/** Default constructor. */
FSceneViewState::FSceneViewState()
	: OcclusionQueryPool(RQT_Occlusion)
{
	UniqueID = FSceneViewState_UniqueID.Increment();
	OcclusionFrameCounter = 0;
	LastRenderTime = -FLT_MAX;
	LastRenderTimeDelta = 0.0f;
	MotionBlurTimeScale = 1.0f;
	PrevViewMatrixForOcclusionQuery.SetIdentity();
	PrevViewOriginForOcclusionQuery = FVector::ZeroVector;
#if !(UE_BUILD_SHIPPING || UE_BUILD_TEST)
	bIsFreezing = false;
	bIsFrozen = false;
	bIsFrozenViewMatricesCached = false;
#endif
	// Register this object as a resource, so it will receive device reset notifications.
	if ( IsInGameThread() )
	{
		BeginInitResource(this);
	}
	else
	{
		InitResource();
	}
	CachedVisibilityChunk = NULL;
	CachedVisibilityHandlerId = INDEX_NONE;
	CachedVisibilityBucketIndex = INDEX_NONE;
	CachedVisibilityChunkIndex = INDEX_NONE;
	MIDUsedCount = 0;
	TemporalAASampleIndex = 0;
	TemporalAASampleCount = 1;
	FrameIndexMod8 = 0;
	DistanceFieldTemporalSampleIndex = 0;
	AOTileIntersectionResources = NULL;
	AOScreenGridResources = NULL;
	bDOFHistory = true;
	bDOFHistory2 = true;

	bSequencerIsPaused = false;

	LightPropagationVolume = NULL; 

	bIsStereoView = false;

	HeightfieldLightingAtlas = NULL;

	for (int32 CascadeIndex = 0; CascadeIndex < ARRAY_COUNT(TranslucencyLightingCacheAllocations); CascadeIndex++)
	{
		TranslucencyLightingCacheAllocations[CascadeIndex] = NULL;
	}

	bInitializedGlobalDistanceFieldOrigins = false;
	GlobalDistanceFieldUpdateIndex = 0;

	ShadowOcclusionQueryMaps.Empty(FOcclusionQueryHelpers::MaxBufferedOcclusionFrames);
	ShadowOcclusionQueryMaps.AddZeroed(FOcclusionQueryHelpers::MaxBufferedOcclusionFrames);	

	bValidEyeAdaptation = false;

	LastAutoDownsampleChangeTime = 0;
	SmoothedHalfResTranslucencyGPUDuration = 0;
	SmoothedFullResTranslucencyGPUDuration = 0;
	bShouldAutoDownsampleTranslucency = false;
}

void DestroyRenderResource(FRenderResource* RenderResource)
{
	if (RenderResource) 
	{
		ENQUEUE_UNIQUE_RENDER_COMMAND_ONEPARAMETER(
			DestroySceneViewStateRenderResource,
			FRenderResource*, RenderResourceRT, RenderResource,
			{
				RenderResourceRT->ReleaseResource();
				delete RenderResourceRT;
			}
		);
	}
}

FSceneViewState::~FSceneViewState()
{
	CachedVisibilityChunk = NULL;

	for (int32 CascadeIndex = 0; CascadeIndex < ARRAY_COUNT(TranslucencyLightingCacheAllocations); CascadeIndex++)
	{
		delete TranslucencyLightingCacheAllocations[CascadeIndex];
	}

	DestroyRenderResource(HeightfieldLightingAtlas);
	DestroyRenderResource(AOTileIntersectionResources);
	AOTileIntersectionResources = NULL;
	DestroyRenderResource(AOScreenGridResources);
	AOScreenGridResources = NULL;
	DestroyLightPropagationVolume();
}

#if WITH_EDITOR

FPixelInspectorData::FPixelInspectorData()
{
	for (int32 i = 0; i < 2; ++i)
	{
		RenderTargetBufferFinalColor[i] = nullptr;
		RenderTargetBufferDepth[i] = nullptr;
		RenderTargetBufferSceneColor[i] = nullptr;
		RenderTargetBufferHDR[i] = nullptr;
		RenderTargetBufferA[i] = nullptr;
		RenderTargetBufferBCDE[i] = nullptr;
	}
}

void FPixelInspectorData::InitializeBuffers(FRenderTarget* BufferFinalColor, FRenderTarget* BufferSceneColor, FRenderTarget* BufferDepth, FRenderTarget* BufferHDR, FRenderTarget* BufferA, FRenderTarget* BufferBCDE, int32 BufferIndex)
{
	RenderTargetBufferFinalColor[BufferIndex] = BufferFinalColor;
	RenderTargetBufferDepth[BufferIndex] = BufferDepth;
	RenderTargetBufferSceneColor[BufferIndex] = BufferSceneColor;
	RenderTargetBufferHDR[BufferIndex] = BufferHDR;
	RenderTargetBufferA[BufferIndex] = BufferA;
	RenderTargetBufferBCDE[BufferIndex] = BufferBCDE;

	check(RenderTargetBufferBCDE[BufferIndex] != nullptr);
	
	FIntPoint BufferSize = RenderTargetBufferBCDE[BufferIndex]->GetSizeXY();
	check(BufferSize.X == 4 && BufferSize.Y == 1);

	if (RenderTargetBufferA[BufferIndex] != nullptr)
	{
		BufferSize = RenderTargetBufferA[BufferIndex]->GetSizeXY();
		check(BufferSize.X == 1 && BufferSize.Y == 1);
	}
	
	if (RenderTargetBufferFinalColor[BufferIndex] != nullptr)
	{
		BufferSize = RenderTargetBufferFinalColor[BufferIndex]->GetSizeXY();
		//The Final color grab an area and can change depending on the setup
		//It should at least contain 1 pixel but can be 3x3 or more
		check(BufferSize.X > 0 && BufferSize.Y > 0);
	}

	if (RenderTargetBufferDepth[BufferIndex] != nullptr)
	{
		BufferSize = RenderTargetBufferDepth[BufferIndex]->GetSizeXY();
		check(BufferSize.X == 1 && BufferSize.Y == 1);
	}

	if (RenderTargetBufferSceneColor[BufferIndex] != nullptr)
	{
		BufferSize = RenderTargetBufferSceneColor[BufferIndex]->GetSizeXY();
		check(BufferSize.X == 1 && BufferSize.Y == 1);
	}

	if (RenderTargetBufferHDR[BufferIndex] != nullptr)
	{
		BufferSize = RenderTargetBufferHDR[BufferIndex]->GetSizeXY();
		check(BufferSize.X == 1 && BufferSize.Y == 1);
	}
}

bool FPixelInspectorData::AddPixelInspectorRequest(FPixelInspectorRequest *PixelInspectorRequest)
{
	if (PixelInspectorRequest == nullptr)
		return false;
	FIntPoint PixelPosition = PixelInspectorRequest->SourcePixelPosition;
	if (Requests.Contains(PixelPosition))
		return false;
	
	//Remove the oldest request since the new request use the buffer
	if (Requests.Num() > 1)
	{
		FIntPoint FirstKey(-1, -1);
		for (auto kvp : Requests)
		{
			FirstKey = kvp.Key;
			break;
		}
		if (Requests.Contains(FirstKey))
		{
			Requests.Remove(FirstKey);
		}
	}
	Requests.Add(PixelPosition, PixelInspectorRequest);
	return true;
}

#endif //WITH_EDITOR

FDistanceFieldSceneData::FDistanceFieldSceneData(EShaderPlatform ShaderPlatform) 
	: NumObjectsInBuffer(0)
	, ObjectBuffers(NULL)
	, SurfelBuffers(NULL)
	, InstancedSurfelBuffers(NULL)
	, AtlasGeneration(0)
{
	static const auto CVar = IConsoleManager::Get().FindTConsoleVariableDataInt(TEXT("r.GenerateMeshDistanceFields"));

	bTrackAllPrimitives = (DoesPlatformSupportDistanceFieldAO(ShaderPlatform) || DoesPlatformSupportDistanceFieldShadowing(ShaderPlatform)) && CVar->GetValueOnGameThread() != 0;
	
	bCanUse16BitObjectIndices = !IsMetalPlatform(ShaderPlatform);
}

FDistanceFieldSceneData::~FDistanceFieldSceneData() 
{
	delete ObjectBuffers;
}

void FDistanceFieldSceneData::AddPrimitive(FPrimitiveSceneInfo* InPrimitive)
{
	const FPrimitiveSceneProxy* Proxy = InPrimitive->Proxy;

	if ((bTrackAllPrimitives || Proxy->CastsDynamicIndirectShadow())
		&& Proxy->CastsDynamicShadow()
		&& Proxy->AffectsDistanceFieldLighting())
	{
		if (Proxy->SupportsHeightfieldRepresentation())
		{
			HeightfieldPrimitives.Add(InPrimitive);
			FBoxSphereBounds PrimitiveBounds = Proxy->GetBounds();
			FGlobalDFCacheType CacheType = Proxy->IsOftenMoving() ? GDF_Full : GDF_MostlyStatic;
			PrimitiveModifiedBounds[CacheType].Add(FVector4(PrimitiveBounds.Origin, PrimitiveBounds.SphereRadius));
		}

		if (Proxy->SupportsDistanceFieldRepresentation())
		{
			checkSlow(!PendingAddOperations.Contains(InPrimitive));
			checkSlow(!PendingUpdateOperations.Contains(InPrimitive));
			PendingAddOperations.Add(InPrimitive);
		}
	}
}

void FDistanceFieldSceneData::UpdatePrimitive(FPrimitiveSceneInfo* InPrimitive)
{
	const FPrimitiveSceneProxy* Proxy = InPrimitive->Proxy;

	if ((bTrackAllPrimitives || Proxy->CastsDynamicIndirectShadow()) 
		&& Proxy->CastsDynamicShadow() 
		&& Proxy->AffectsDistanceFieldLighting()
		&& Proxy->SupportsDistanceFieldRepresentation() 
		&& !PendingAddOperations.Contains(InPrimitive)
		// This is needed to prevent infinite buildup when DF features are off such that the pending operations don't get consumed
		&& !PendingUpdateOperations.Contains(InPrimitive)
		// This can happen when the primitive fails to allocate from the SDF atlas
		&& InPrimitive->DistanceFieldInstanceIndices.Num() > 0)
	{
		PendingUpdateOperations.Add(InPrimitive);
	}
}

void FDistanceFieldSceneData::RemovePrimitive(FPrimitiveSceneInfo* InPrimitive)
{
	const FPrimitiveSceneProxy* Proxy = InPrimitive->Proxy;

	if ((bTrackAllPrimitives || Proxy->CastsDynamicIndirectShadow()) 
		&& Proxy->AffectsDistanceFieldLighting())
	{
		if (Proxy->SupportsDistanceFieldRepresentation())
		{
			PendingAddOperations.Remove(InPrimitive);
			PendingUpdateOperations.Remove(InPrimitive);

			if (InPrimitive->DistanceFieldInstanceIndices.Num() > 0)
			{
				PendingRemoveOperations.Add(FPrimitiveRemoveInfo(InPrimitive));
			}
			
			InPrimitive->DistanceFieldInstanceIndices.Empty();
		}

		if (Proxy->SupportsHeightfieldRepresentation())
		{
			HeightfieldPrimitives.Remove(InPrimitive);

			FBoxSphereBounds PrimitiveBounds = Proxy->GetBounds();
			FGlobalDFCacheType CacheType = Proxy->IsOftenMoving() ? GDF_Full : GDF_MostlyStatic;
			PrimitiveModifiedBounds[CacheType].Add(FVector4(PrimitiveBounds.Origin, PrimitiveBounds.SphereRadius));
		}
	}
}

void FDistanceFieldSceneData::Release()
{
	if (ObjectBuffers)
	{
		ObjectBuffers->Release();
	}
}

void FDistanceFieldSceneData::VerifyIntegrity()
{
	check(NumObjectsInBuffer == PrimitiveInstanceMapping.Num());

	for (int32 PrimitiveInstanceIndex = 0; PrimitiveInstanceIndex < PrimitiveInstanceMapping.Num(); PrimitiveInstanceIndex++)
	{
		const FPrimitiveAndInstance& PrimitiveAndInstance = PrimitiveInstanceMapping[PrimitiveInstanceIndex];

		check(PrimitiveAndInstance.Primitive && PrimitiveAndInstance.Primitive->DistanceFieldInstanceIndices.Num() > 0);
		check(PrimitiveAndInstance.Primitive->DistanceFieldInstanceIndices.IsValidIndex(PrimitiveAndInstance.InstanceIndex));

		const int32 InstanceIndex = PrimitiveAndInstance.Primitive->DistanceFieldInstanceIndices[PrimitiveAndInstance.InstanceIndex];
		check(InstanceIndex == PrimitiveInstanceIndex || InstanceIndex == -1);
	}
}

void FScene::UpdateSceneSettings(AWorldSettings* WorldSettings)
{
	ENQUEUE_UNIQUE_RENDER_COMMAND_FOURPARAMETER(
		UpdateSceneSettings,
		FScene*, Scene, this,
		float, DefaultMaxDistanceFieldOcclusionDistance, WorldSettings->DefaultMaxDistanceFieldOcclusionDistance,
		float, GlobalDistanceFieldViewDistance, WorldSettings->GlobalDistanceFieldViewDistance,
		float, DynamicIndirectShadowsSelfShadowingIntensity, FMath::Clamp(WorldSettings->DynamicIndirectShadowsSelfShadowingIntensity, 0.0f, 1.0f),
	{
		Scene->DefaultMaxDistanceFieldOcclusionDistance = DefaultMaxDistanceFieldOcclusionDistance;
		Scene->GlobalDistanceFieldViewDistance = GlobalDistanceFieldViewDistance;
		Scene->DynamicIndirectShadowsSelfShadowingIntensity = DynamicIndirectShadowsSelfShadowingIntensity;
	});
}

/**
 * Sets the FX system associated with the scene.
 */
void FScene::SetFXSystem( class FFXSystemInterface* InFXSystem )
{
	FXSystem = InFXSystem;
}

/**
 * Get the FX system associated with the scene.
 */
FFXSystemInterface* FScene::GetFXSystem()
{
	return FXSystem;
}

void FScene::SetClearMotionBlurInfoGameThread()
{
	check(IsInGameThread());

	ENQUEUE_UNIQUE_RENDER_COMMAND_ONEPARAMETER(
		ShouldClearMBInfoCommand,
		FScene*,Scene,this,
	{
		Scene->MotionBlurInfoData.SetClearMotionBlurInfo();
	});
}

void FScene::UpdateParameterCollections(const TArray<FMaterialParameterCollectionInstanceResource*>& InParameterCollections)
{
	// Empy the scene's map so any unused uniform buffers will be released
	ENQUEUE_UNIQUE_RENDER_COMMAND_ONEPARAMETER(
		ClearParameterCollectionsCommand,
		FScene*,Scene,this,
	{
		Scene->ParameterCollections.Empty();
	});

	// Add each existing parameter collection id and its uniform buffer
	for (int32 CollectionIndex = 0; CollectionIndex < InParameterCollections.Num(); CollectionIndex++)
	{
		ENQUEUE_UNIQUE_RENDER_COMMAND_TWOPARAMETER(
			AddParameterCollectionCommand,
			FScene*,Scene,this,
			FMaterialParameterCollectionInstanceResource*,InstanceResource,InParameterCollections[CollectionIndex],
		{
			Scene->ParameterCollections.Add(InstanceResource->GetId(), InstanceResource->GetUniformBuffer());
		});
	}
}

SIZE_T FScene::GetSizeBytes() const
{
	return sizeof(*this) 
		+ Primitives.GetAllocatedSize()
		+ Lights.GetAllocatedSize()
		+ StaticMeshes.GetAllocatedSize()
		+ ExponentialFogs.GetAllocatedSize()
		+ WindSources.GetAllocatedSize()
		+ SpeedTreeVertexFactoryMap.GetAllocatedSize()
		+ SpeedTreeWindComputationMap.GetAllocatedSize()
		+ LightOctree.GetSizeBytes()
		+ PrimitiveOctree.GetSizeBytes();
}

void FScene::CheckPrimitiveArrays()
{
	check(Primitives.Num() == PrimitiveBounds.Num());
	check(Primitives.Num() == PrimitiveVisibilityIds.Num());
	check(Primitives.Num() == PrimitiveOcclusionFlags.Num());
	check(Primitives.Num() == PrimitiveComponentIds.Num());
	check(Primitives.Num() == PrimitiveOcclusionBounds.Num());
}

void FScene::AddPrimitiveSceneInfo_RenderThread(FRHICommandListImmediate& RHICmdList, FPrimitiveSceneInfo* PrimitiveSceneInfo)
{
	SCOPE_CYCLE_COUNTER(STAT_AddScenePrimitiveRenderThreadTime);
	
	CheckPrimitiveArrays();

	int32 PrimitiveIndex = Primitives.Add(PrimitiveSceneInfo);
	PrimitiveSceneInfo->PackedIndex = PrimitiveIndex;

	PrimitiveBounds.AddUninitialized();
	PrimitiveVisibilityIds.AddUninitialized();
	PrimitiveOcclusionFlags.AddUninitialized();
	PrimitiveComponentIds.AddUninitialized();
	PrimitiveOcclusionBounds.AddUninitialized();

	CheckPrimitiveArrays();

	// Add the primitive to its shadow parent's linked list of children.
	// Note: must happen before AddToScene because AddToScene depends on LightingAttachmentRoot
	PrimitiveSceneInfo->LinkAttachmentGroup();

	// Set lod Parent information if valid
	PrimitiveSceneInfo->LinkLODParentComponent();

	// Add the primitive to the scene.
	PrimitiveSceneInfo->AddToScene(RHICmdList, true);

	DistanceFieldSceneData.AddPrimitive(PrimitiveSceneInfo);

	// LOD Parent, if this is LOD parent, we should update Proxy Scene Info
	// LOD parent gets removed WHEN no children is accessing
	// LOD parent can be recreated as scene updates
	// I update if the parent component ID is still valid
	// @Todo : really remove it if you know this is being destroyed - should happen from game thread as streaming in/out
	SceneLODHierarchy.UpdateNodeSceneInfo(PrimitiveSceneInfo->PrimitiveComponentId, PrimitiveSceneInfo);
}

/**
 * Verifies that a component is added to the proper scene
 *
 * @param Component Component to verify
 * @param World World who's scene the primitive is being attached to
 */
FORCEINLINE static void VerifyProperPIEScene(UPrimitiveComponent* Component, UWorld* World)
{
#if CHECK_FOR_PIE_PRIMITIVE_ATTACH_SCENE_MISMATCH
	checkf(Component->GetOuter() == GetTransientPackage() || 
		(FPackageName::GetLongPackageAssetName(Component->GetOutermost()->GetName()).StartsWith(PLAYWORLD_PACKAGE_PREFIX) == 
		FPackageName::GetLongPackageAssetName(World->GetOutermost()->GetName()).StartsWith(PLAYWORLD_PACKAGE_PREFIX)),
		TEXT("The component %s was added to the wrong world's scene (due to PIE). The callstack should tell you why"), 
		*Component->GetFullName()
		);
#endif
}

FReadOnlyCVARCache* FReadOnlyCVARCache::Singleton = nullptr;

FReadOnlyCVARCache::FReadOnlyCVARCache()
{
	static const auto CVarSupportAtmosphericFog = IConsoleManager::Get().FindTConsoleVariableDataInt(TEXT("r.SupportAtmosphericFog"));
	static const auto CVarSupportStationarySkylight = IConsoleManager::Get().FindTConsoleVariableDataInt(TEXT("r.SupportStationarySkylight"));
	static const auto CVarSupportLowQualityLightmaps = IConsoleManager::Get().FindTConsoleVariableDataInt(TEXT("r.SupportLowQualityLightmaps"));
	static const auto CVarSupportPointLightWholeSceneShadows = IConsoleManager::Get().FindTConsoleVariableDataInt(TEXT("r.SupportPointLightWholeSceneShadows"));
	static const auto CVarSupportAllShaderPermutations = IConsoleManager::Get().FindTConsoleVariableDataInt(TEXT("r.SupportAllShaderPermutations"));	
	static const auto CVarVertexFoggingForOpaque = IConsoleManager::Get().FindTConsoleVariableDataInt(TEXT("r.VertexFoggingForOpaque"));	
	static const auto CVarForwardShading = IConsoleManager::Get().FindTConsoleVariableDataInt(TEXT("r.ForwardShading"));
	static const auto CVarAllowStaticLighting = IConsoleManager::Get().FindTConsoleVariableDataInt(TEXT("r.AllowStaticLighting"));

	static const auto CVarMobileAllowMovableDirectionalLights = IConsoleManager::Get().FindTConsoleVariableDataInt(TEXT("r.Mobile.AllowMovableDirectionalLights"));
	static const auto CVarMobileEnableStaticAndCSMShadowReceivers = IConsoleManager::Get().FindTConsoleVariableDataInt(TEXT("r.Mobile.EnableStaticAndCSMShadowReceivers"));
	static const auto CVarAllReceiveDynamicCSM = IConsoleManager::Get().FindTConsoleVariableDataInt(TEXT("r.AllReceiveDynamicCSM"));
	static const auto CVarMobileAllowDistanceFieldShadows = IConsoleManager::Get().FindTConsoleVariableDataInt(TEXT("r.Mobile.AllowDistanceFieldShadows"));
	static const auto CVarMobileNumDynamicPointLights = IConsoleManager::Get().FindTConsoleVariableDataInt(TEXT("r.MobileNumDynamicPointLights"));

	const bool bForceAllPermutations = CVarSupportAllShaderPermutations && CVarSupportAllShaderPermutations->GetValueOnAnyThread() != 0;

	bEnableAtmosphericFog = !CVarSupportAtmosphericFog || CVarSupportAtmosphericFog->GetValueOnAnyThread() != 0 || bForceAllPermutations;
	bEnableStationarySkylight = !CVarSupportStationarySkylight || CVarSupportStationarySkylight->GetValueOnAnyThread() != 0 || bForceAllPermutations;
	bEnablePointLightShadows = !CVarSupportPointLightWholeSceneShadows || CVarSupportPointLightWholeSceneShadows->GetValueOnAnyThread() != 0 || bForceAllPermutations;
	bEnableLowQualityLightmaps = !CVarSupportLowQualityLightmaps || CVarSupportLowQualityLightmaps->GetValueOnAnyThread() != 0 || bForceAllPermutations;
	bAllowStaticLighting = CVarAllowStaticLighting->GetValueOnAnyThread() != 0;

	// mobile
	bMobileAllowMovableDirectionalLights = CVarMobileAllowMovableDirectionalLights->GetValueOnAnyThread() != 0;
	bAllReceiveDynamicCSM = CVarAllReceiveDynamicCSM->GetValueOnAnyThread() != 0;
	bMobileAllowDistanceFieldShadows = CVarMobileAllowDistanceFieldShadows->GetValueOnAnyThread() != 0;
	bMobileEnableStaticAndCSMShadowReceivers = CVarMobileEnableStaticAndCSMShadowReceivers->GetValueOnAnyThread() != 0;
	NumMobileMovablePointLights = CVarMobileNumDynamicPointLights->GetValueOnAnyThread();

	// Only enable VertexFoggingForOpaque if ForwardShading is enabled 
	const bool bForwardShading = CVarForwardShading && CVarForwardShading->GetValueOnAnyThread() != 0;
	bEnableVertexFoggingForOpaque = bForwardShading && ( !CVarVertexFoggingForOpaque || CVarVertexFoggingForOpaque->GetValueOnAnyThread() != 0 );

	const bool bShowMissmatchedLowQualityLightmapsWarning = (!bEnableLowQualityLightmaps) && (GEngine->bShouldGenerateLowQualityLightmaps_DEPRECATED);
	if ( bShowMissmatchedLowQualityLightmapsWarning )
	{
		UE_LOG(LogRenderer, Warning, TEXT("Mismatch between bShouldGenerateLowQualityLightmaps(%d) and r.SupportLowQualityLightmaps(%d), UEngine::bShouldGenerateLowQualityLightmaps has been deprecated please use r.SupportLowQualityLightmaps instead"), GEngine->bShouldGenerateLowQualityLightmaps_DEPRECATED, bEnableLowQualityLightmaps);
	}
}

FScene::FScene(UWorld* InWorld, bool bInRequiresHitProxies, bool bInIsEditorScene, bool bCreateFXSystem, ERHIFeatureLevel::Type InFeatureLevel)
:	World(InWorld)
,	FXSystem(NULL)
,	bStaticDrawListsMobileHDR(false)
,	bStaticDrawListsMobileHDR32bpp(false)
,	StaticDrawListsEarlyZPassMode(0)
,	StaticDrawShaderPipelines(0)
,	bScenesPrimitivesNeedStaticMeshElementUpdate(false)
,	SkyLight(NULL)
,	SimpleDirectionalLight(NULL)
,	SunLight(NULL)
,	ReflectionSceneData(InFeatureLevel)
,	IndirectLightingCache(InFeatureLevel)
,	DistanceFieldSceneData(GShaderPlatformForFeatureLevel[InFeatureLevel])
,	PreshadowCacheLayout(0, 0, 0, 0, false, false)
,	AtmosphericFog(NULL)
,	PrecomputedVisibilityHandler(NULL)
,	LightOctree(FVector::ZeroVector,HALF_WORLD_MAX)
,	PrimitiveOctree(FVector::ZeroVector,HALF_WORLD_MAX)
,	bRequiresHitProxies(bInRequiresHitProxies)
,	bIsEditorScene(bInIsEditorScene)
,	NumUncachedStaticLightingInteractions(0)
,	NumMobileStaticAndCSMLights_RenderThread(0)
,	NumMobileMovableDirectionalLights_RenderThread(0)
,	GPUSkinCache(nullptr)
,	SceneLODHierarchy(this)
,	DefaultMaxDistanceFieldOcclusionDistance(InWorld->GetWorldSettings()->DefaultMaxDistanceFieldOcclusionDistance)
,	GlobalDistanceFieldViewDistance(InWorld->GetWorldSettings()->GlobalDistanceFieldViewDistance)
,	DynamicIndirectShadowsSelfShadowingIntensity(FMath::Clamp(InWorld->GetWorldSettings()->DynamicIndirectShadowsSelfShadowingIntensity, 0.0f, 1.0f))
,	ReadOnlyCVARCache(FReadOnlyCVARCache::Get())
,	NumVisibleLights_GameThread(0)
,	NumEnabledSkylights_GameThread(0)
,	SceneFrameNumber(0)
{
	FMemory::Memzero(MobileDirectionalLights);

	check(World);
	World->Scene = this;

	FeatureLevel = World->FeatureLevel;

	static auto* MobileHDRCvar = IConsoleManager::Get().FindTConsoleVariableDataInt(TEXT("r.MobileHDR"));
	static auto* MobileHDR32bppModeCvar = IConsoleManager::Get().FindTConsoleVariableDataInt(TEXT("r.MobileHDR32bppMode"));
	bStaticDrawListsMobileHDR = MobileHDRCvar->GetValueOnAnyThread() == 1;
	bStaticDrawListsMobileHDR32bpp = bStaticDrawListsMobileHDR && (GSupportsRenderTargetFormat_PF_FloatRGBA == false || MobileHDR32bppModeCvar->GetValueOnAnyThread() != 0);

	static auto* EarlyZPassCvar = IConsoleManager::Get().FindTConsoleVariableDataInt(TEXT("r.EarlyZPass"));
	StaticDrawListsEarlyZPassMode = EarlyZPassCvar->GetValueOnAnyThread();

	static auto* ShaderPipelinesCvar = IConsoleManager::Get().FindTConsoleVariableDataInt(TEXT("r.ShaderPipelines"));
	StaticDrawShaderPipelines = ShaderPipelinesCvar->GetValueOnAnyThread();

	if (World->FXSystem)
	{
		FFXSystemInterface::Destroy(World->FXSystem);
	}

	if (bCreateFXSystem)
	{
		World->CreateFXSystem();
	}
	else
	{
		World->FXSystem = NULL;
		SetFXSystem(NULL);
	}

	if (IsGPUSkinCacheAvailable())
	{
		const bool bRequiresMemoryLimit = !bInIsEditorScene;
		GPUSkinCache = new FGPUSkinCache(bRequiresMemoryLimit);
	}

	World->UpdateParameterCollectionInstances(false);
}

FScene::~FScene()
{
#if 0 // if you have component that has invalid scene, try this code to see this is reason. 
	for (FObjectIterator Iter(UActorComponent::StaticClass()); Iter; ++Iter)
	{
		UActorComponent * ActorComp = CastChecked<UActorComponent>(*Iter);
		if (ActorComp->GetScene() == this)
		{
			UE_LOG(LogRenderer, Log, TEXT("%s's scene is going to get invalidated"), *ActorComp->GetName());
		}
	}
#endif

	ReflectionSceneData.CubemapArray.ReleaseResource();
	IndirectLightingCache.ReleaseResource();
	DistanceFieldSceneData.Release();

	if (AtmosphericFog)
	{
		delete AtmosphericFog;
		AtmosphericFog = nullptr;
	}

	if (GPUSkinCache)
	{
		delete GPUSkinCache;
		GPUSkinCache = nullptr;
	}
}

void FScene::AddPrimitive(UPrimitiveComponent* Primitive)
{
	SCOPE_CYCLE_COUNTER(STAT_AddScenePrimitiveGT);

	checkf(!Primitive->IsUnreachable(), TEXT("%s"), *Primitive->GetFullName());

	const float WorldTime = GetWorld()->GetTimeSeconds();
	// Save the world transform for next time the primitive is added to the scene
	float DeltaTime = WorldTime - Primitive->LastSubmitTime;
	if ( DeltaTime < -0.0001f || Primitive->LastSubmitTime < 0.0001f )
	{
		// Time was reset?
		Primitive->LastSubmitTime = WorldTime;
	}
	else if ( DeltaTime > 0.0001f )
	{
		// First call for the new frame?
		Primitive->LastSubmitTime = WorldTime;
	}

	// Create the primitive's scene proxy.
	FPrimitiveSceneProxy* PrimitiveSceneProxy = Primitive->CreateSceneProxy();
	Primitive->SceneProxy = PrimitiveSceneProxy;
	if(!PrimitiveSceneProxy)
	{
		// Primitives which don't have a proxy are irrelevant to the scene manager.
		return;
	}

	// Create the primitive scene info.
	FPrimitiveSceneInfo* PrimitiveSceneInfo = new FPrimitiveSceneInfo(Primitive, this);
	PrimitiveSceneProxy->PrimitiveSceneInfo = PrimitiveSceneInfo;

	// Cache the primitive's initial transform.
	FMatrix RenderMatrix = Primitive->GetRenderMatrix();
	FVector AttachmentRootPosition(0);

	AActor* AttachmentRoot = Primitive->GetAttachmentRootActor();
	if (AttachmentRoot)
	{
		AttachmentRootPosition = AttachmentRoot->GetActorLocation();
	}

	struct FCreateRenderThreadParameters
	{
		FPrimitiveSceneProxy* PrimitiveSceneProxy;
		FMatrix RenderMatrix;
		FBoxSphereBounds WorldBounds;
		FVector AttachmentRootPosition;
		FBoxSphereBounds LocalBounds;
	};
	FCreateRenderThreadParameters Params =
	{
		PrimitiveSceneProxy,
		RenderMatrix,
		Primitive->Bounds,
		AttachmentRootPosition,
		Primitive->CalcBounds(FTransform::Identity)
	};

	// Help track down primitive with bad bounds way before the it gets to the Renderer
	ensureMsgf(!Primitive->Bounds.BoxExtent.ContainsNaN() && !Primitive->Bounds.Origin.ContainsNaN() && !FMath::IsNaN(Primitive->Bounds.SphereRadius) && FMath::IsFinite(Primitive->Bounds.SphereRadius),
			TEXT("Nans found on Bounds for Primitive %s: Origin %s, BoxExtent %s, SphereRadius %f"), *Primitive->GetName(), *Primitive->Bounds.Origin.ToString(), *Primitive->Bounds.BoxExtent.ToString(), Primitive->Bounds.SphereRadius);

	// Create any RenderThreadResources required.
	ENQUEUE_RENDER_COMMAND(CreateRenderThreadResourcesCommand)(
		[Params](FRHICommandListImmediate& RHICmdList)
	{
		FPrimitiveSceneProxy* SceneProxy = Params.PrimitiveSceneProxy;
		FScopeCycleCounter Context(SceneProxy->GetStatId());
		SceneProxy->SetTransform(Params.RenderMatrix, Params.WorldBounds, Params.LocalBounds, Params.AttachmentRootPosition);

		// Create any RenderThreadResources required.
		SceneProxy->CreateRenderThreadResources();
	});

	INC_DWORD_STAT_BY( STAT_GameToRendererMallocTotal, PrimitiveSceneProxy->GetMemoryFootprint() + PrimitiveSceneInfo->GetMemoryFootprint() );

	// Verify the primitive is valid (this will compile away to a nop without CHECK_FOR_PIE_PRIMITIVE_ATTACH_SCENE_MISMATCH)
	VerifyProperPIEScene(Primitive, World);

	// Increment the attachment counter, the primitive is about to be attached to the scene.
	Primitive->AttachmentCounter.Increment();

	// Send a command to the rendering thread to add the primitive to the scene.
	FScene* Scene = this;
	ENQUEUE_RENDER_COMMAND(AddPrimitiveCommand)(
		[Scene, PrimitiveSceneInfo](FRHICommandListImmediate& RHICmdList)
		{
			FScopeCycleCounter Context(PrimitiveSceneInfo->Proxy->GetStatId());
			Scene->AddPrimitiveSceneInfo_RenderThread(RHICmdList, PrimitiveSceneInfo);
		});

}

void FScene::UpdatePrimitiveTransform_RenderThread(FRHICommandListImmediate& RHICmdList, FPrimitiveSceneProxy* PrimitiveSceneProxy, const FBoxSphereBounds& WorldBounds, const FBoxSphereBounds& LocalBounds, const FMatrix& LocalToWorld, const FVector& AttachmentRootPosition)
{
	SCOPE_CYCLE_COUNTER(STAT_UpdatePrimitiveTransformRenderThreadTime);

	const bool bUpdateStaticDrawLists = !PrimitiveSceneProxy->StaticElementsAlwaysUseProxyPrimitiveUniformBuffer();

	// Remove the primitive from the scene at its old location
	// (note that the octree update relies on the bounds not being modified yet).
	PrimitiveSceneProxy->GetPrimitiveSceneInfo()->RemoveFromScene(bUpdateStaticDrawLists);
	
	// Update the primitive motion blur information.
	// hack
	FScene* Scene = (FScene*)&PrimitiveSceneProxy->GetScene();

	Scene->MotionBlurInfoData.UpdatePrimitiveMotionBlur(PrimitiveSceneProxy->GetPrimitiveSceneInfo());
	
	// Update the primitive transform.
	PrimitiveSceneProxy->SetTransform(LocalToWorld, WorldBounds, LocalBounds, AttachmentRootPosition);

	DistanceFieldSceneData.UpdatePrimitive(PrimitiveSceneProxy->GetPrimitiveSceneInfo());

	// If the primitive has static mesh elements, it should have returned true from ShouldRecreateProxyOnUpdateTransform!
	check(!(bUpdateStaticDrawLists && PrimitiveSceneProxy->GetPrimitiveSceneInfo()->StaticMeshes.Num()));

	// Re-add the primitive to the scene with the new transform.
	PrimitiveSceneProxy->GetPrimitiveSceneInfo()->AddToScene(RHICmdList, bUpdateStaticDrawLists);
}

void FScene::UpdatePrimitiveTransform(UPrimitiveComponent* Primitive)
{
	SCOPE_CYCLE_COUNTER(STAT_UpdatePrimitiveTransformGT);

	// Save the world transform for next time the primitive is added to the scene
	const float WorldTime = GetWorld()->GetTimeSeconds();
	float DeltaTime = WorldTime - Primitive->LastSubmitTime;
	if ( DeltaTime < -0.0001f || Primitive->LastSubmitTime < 0.0001f )
	{
		// Time was reset?
		Primitive->LastSubmitTime = WorldTime;
	}
	else if ( DeltaTime > 0.0001f )
	{
		// First call for the new frame?
		Primitive->LastSubmitTime = WorldTime;
	}

	if(Primitive->SceneProxy)
	{
		// Check if the primitive needs to recreate its proxy for the transform update.
		if(Primitive->ShouldRecreateProxyOnUpdateTransform())
		{
			// Re-add the primitive from scratch to recreate the primitive's proxy.
			RemovePrimitive(Primitive);
			AddPrimitive(Primitive);
		}
		else
		{
			FVector AttachmentRootPosition(0);

			AActor* Actor = Primitive->GetAttachmentRootActor();
			if (Actor != NULL)
			{
				AttachmentRootPosition = Actor->GetActorLocation();
			}

			struct FPrimitiveUpdateParams
			{
				FScene* Scene;
				FPrimitiveSceneProxy* PrimitiveSceneProxy;
				FBoxSphereBounds WorldBounds;
				FBoxSphereBounds LocalBounds;
				FMatrix LocalToWorld;
				FVector AttachmentRootPosition;
			};

			FPrimitiveUpdateParams UpdateParams;
			UpdateParams.Scene = this;
			UpdateParams.PrimitiveSceneProxy = Primitive->SceneProxy;
			UpdateParams.WorldBounds = Primitive->Bounds;
			UpdateParams.LocalToWorld = Primitive->GetRenderMatrix();
			UpdateParams.AttachmentRootPosition = AttachmentRootPosition;
			UpdateParams.LocalBounds = Primitive->CalcBounds(FTransform::Identity);

			// Help track down primitive with bad bounds way before the it gets to the Renderer
			ensureMsgf(!Primitive->Bounds.BoxExtent.ContainsNaN() && !Primitive->Bounds.Origin.ContainsNaN() && !FMath::IsNaN(Primitive->Bounds.SphereRadius) && FMath::IsFinite(Primitive->Bounds.SphereRadius),
				TEXT("Nans found on Bounds for Primitive %s: Origin %s, BoxExtent %s, SphereRadius %f"), *Primitive->GetName(), *Primitive->Bounds.Origin.ToString(), *Primitive->Bounds.BoxExtent.ToString(), Primitive->Bounds.SphereRadius);

			ENQUEUE_RENDER_COMMAND(UpdateTransformCommand)(
				[UpdateParams](FRHICommandListImmediate& RHICmdList)
				{
					FScopeCycleCounter Context(UpdateParams.PrimitiveSceneProxy->GetStatId());
					UpdateParams.Scene->UpdatePrimitiveTransform_RenderThread(RHICmdList, UpdateParams.PrimitiveSceneProxy, UpdateParams.WorldBounds, UpdateParams.LocalBounds, UpdateParams.LocalToWorld, UpdateParams.AttachmentRootPosition);
				});
		}
	}
	else
	{
		// If the primitive doesn't have a scene info object yet, it must be added from scratch.
		AddPrimitive(Primitive);
	}
}

void FScene::UpdatePrimitiveLightingAttachmentRoot(UPrimitiveComponent* Primitive)
{
	const UPrimitiveComponent* NewLightingAttachmentRoot = Cast<UPrimitiveComponent>(Primitive->GetAttachmentRoot());

	if (NewLightingAttachmentRoot == Primitive)
	{
		NewLightingAttachmentRoot = NULL;
	}

	FPrimitiveComponentId NewComponentId = NewLightingAttachmentRoot ? NewLightingAttachmentRoot->ComponentId : FPrimitiveComponentId();

	if (Primitive->SceneProxy)
	{
		ENQUEUE_UNIQUE_RENDER_COMMAND_TWOPARAMETER(
			UpdatePrimitiveAttachment,
			FPrimitiveSceneProxy*,Proxy,Primitive->SceneProxy,
			FPrimitiveComponentId,NewComponentId,NewComponentId,
		{
			FPrimitiveSceneInfo* PrimitiveInfo = Proxy->GetPrimitiveSceneInfo();
			PrimitiveInfo->UnlinkAttachmentGroup();
			PrimitiveInfo->LightingAttachmentRoot = NewComponentId;
			PrimitiveInfo->LinkAttachmentGroup();
		});
	}
}

void FScene::UpdatePrimitiveAttachment(UPrimitiveComponent* Primitive)
{
	TArray<USceneComponent*, TInlineAllocator<1> > ProcessStack;
	ProcessStack.Push(Primitive);

	// Walk down the tree updating, because the scene's attachment data structures must be updated if the root of the attachment tree changes
	while (ProcessStack.Num() > 0)
	{
		USceneComponent* Current = ProcessStack.Pop(/*bAllowShrinking=*/ false);
		if (Current)
		{
			UPrimitiveComponent* CurrentPrimitive = Cast<UPrimitiveComponent>(Current);

			if (CurrentPrimitive
				&& CurrentPrimitive->GetWorld() 
				&& CurrentPrimitive->GetWorld()->Scene == this
				&& CurrentPrimitive->ShouldComponentAddToScene())
			{
				UpdatePrimitiveLightingAttachmentRoot(CurrentPrimitive);
			}

			ProcessStack.Append(Current->GetAttachChildren());
		}
	}
}

FPrimitiveSceneInfo* FScene::GetPrimitiveSceneInfo(int32 PrimitiveIndex)
{
	if(Primitives.IsValidIndex(PrimitiveIndex))
	{
		return Primitives[PrimitiveIndex];
	}
	return NULL;
}

void FScene::RemovePrimitiveSceneInfo_RenderThread(FPrimitiveSceneInfo* PrimitiveSceneInfo)
{
	SCOPE_CYCLE_COUNTER(STAT_RemoveScenePrimitiveTime);

	// clear it up, parent is getting removed
	SceneLODHierarchy.UpdateNodeSceneInfo(PrimitiveSceneInfo->PrimitiveComponentId, nullptr);

	CheckPrimitiveArrays();

	int32 PrimitiveIndex = PrimitiveSceneInfo->PackedIndex;
	Primitives.RemoveAtSwap(PrimitiveIndex);
	PrimitiveBounds.RemoveAtSwap(PrimitiveIndex);
	PrimitiveVisibilityIds.RemoveAtSwap(PrimitiveIndex);
	PrimitiveOcclusionFlags.RemoveAtSwap(PrimitiveIndex);
	PrimitiveComponentIds.RemoveAtSwap(PrimitiveIndex);
	PrimitiveOcclusionBounds.RemoveAtSwap(PrimitiveIndex);
	if (Primitives.IsValidIndex(PrimitiveIndex))
	{
		FPrimitiveSceneInfo* OtherPrimitive = Primitives[PrimitiveIndex];
		OtherPrimitive->PackedIndex = PrimitiveIndex;

		// Invalidate the scene info's PackedIndex now that it is used by another primitive
		PrimitiveSceneInfo->PackedIndex = MAX_int32;
	}
	
	CheckPrimitiveArrays();

	// Update the primitive's motion blur information.
	MotionBlurInfoData.RemovePrimitiveMotionBlur(PrimitiveSceneInfo);

	// Unlink the primitive from its shadow parent.
	PrimitiveSceneInfo->UnlinkAttachmentGroup();

	// Unlink the LOD parent info if valid
	PrimitiveSceneInfo->UnlinkLODParentComponent();

	// Remove the primitive from the scene.
	PrimitiveSceneInfo->RemoveFromScene(true);

	DistanceFieldSceneData.RemovePrimitive(PrimitiveSceneInfo);

	// free the primitive scene proxy.
	delete PrimitiveSceneInfo->Proxy;
}

void FScene::RemovePrimitive( UPrimitiveComponent* Primitive )
{
	SCOPE_CYCLE_COUNTER(STAT_RemoveScenePrimitiveGT);

	FPrimitiveSceneProxy* PrimitiveSceneProxy = Primitive->SceneProxy;

	if(PrimitiveSceneProxy)
	{
		FPrimitiveSceneInfo* PrimitiveSceneInfo = PrimitiveSceneProxy->GetPrimitiveSceneInfo();

		// Disassociate the primitive's scene proxy.
		Primitive->SceneProxy = NULL;

		// Send a command to the rendering thread to remove the primitive from the scene.
		ENQUEUE_UNIQUE_RENDER_COMMAND_THREEPARAMETER(
			FRemovePrimitiveCommand,
			FScene*,Scene,this,
			FPrimitiveSceneInfo*,PrimitiveSceneInfo,PrimitiveSceneProxy->GetPrimitiveSceneInfo(),
			FThreadSafeCounter*,AttachmentCounter,&Primitive->AttachmentCounter,
			{
				FScopeCycleCounter Context(PrimitiveSceneInfo->Proxy->GetStatId());
				Scene->RemovePrimitiveSceneInfo_RenderThread(PrimitiveSceneInfo);
				AttachmentCounter->Decrement();
			});

		// Delete the PrimitiveSceneInfo on the game thread after the rendering thread has processed its removal.
		// This must be done on the game thread because the hit proxy references (and possibly other members) need to be freed on the game thread.
		BeginCleanup(PrimitiveSceneInfo);
	}
}

void FScene::ReleasePrimitive( UPrimitiveComponent* PrimitiveComponent )
{
	// Send a command to the rendering thread to clean up any state dependent on this primitive
	ENQUEUE_UNIQUE_RENDER_COMMAND_TWOPARAMETER(
		FReleasePrimitiveCommand,
		FScene*,Scene,this,
		FPrimitiveComponentId,PrimitiveComponentId,PrimitiveComponent->ComponentId,
	{
		// Free the space in the indirect lighting cache
		Scene->IndirectLightingCache.ReleasePrimitive(PrimitiveComponentId);
	});
}

void FScene::AssignAvailableShadowMapChannelForLight(FLightSceneInfo* LightSceneInfo)
{
	bool bChannelAvailable[4] = { true, true, true, true };

	for (TSparseArray<FLightSceneInfoCompact>::TConstIterator It(Lights); It; ++It)
	{
		const FLightSceneInfoCompact& OtherLightInfo = *It;

		if (OtherLightInfo.LightSceneInfo != LightSceneInfo
			&& OtherLightInfo.LightSceneInfo->Proxy->CastsDynamicShadow()
			&& OtherLightInfo.LightSceneInfo->GetDynamicShadowMapChannel() >= 0
			&& OtherLightInfo.LightSceneInfo->Proxy->AffectsBounds(LightSceneInfo->Proxy->GetBoundingSphere()))
		{
			const int32 OtherShadowMapChannel = OtherLightInfo.LightSceneInfo->GetDynamicShadowMapChannel();

			if (OtherShadowMapChannel < ARRAY_COUNT(bChannelAvailable))
			{
				bChannelAvailable[OtherShadowMapChannel] = false;
			}
		}
	}

	int32 AvailableShadowMapChannel = -1;

	for (int32 TestChannelIndex = 0; TestChannelIndex < ARRAY_COUNT(bChannelAvailable); TestChannelIndex++)
	{
		if (bChannelAvailable[TestChannelIndex])
		{
			AvailableShadowMapChannel = TestChannelIndex;
			break;
		}
	}

	LightSceneInfo->SetDynamicShadowMapChannel(AvailableShadowMapChannel);

	if (AvailableShadowMapChannel == -1)
	{
		OverflowingDynamicShadowedLights.AddUnique(LightSceneInfo->Proxy->GetComponentName());
	}
}

void FScene::AddLightSceneInfo_RenderThread(FLightSceneInfo* LightSceneInfo)
{
	SCOPE_CYCLE_COUNTER(STAT_AddSceneLightTime);

	check(LightSceneInfo->bVisible);

	// Add the light to the light list.
	LightSceneInfo->Id = Lights.Add(FLightSceneInfoCompact(LightSceneInfo));
	const FLightSceneInfoCompact& LightSceneInfoCompact = Lights[LightSceneInfo->Id];

	if (LightSceneInfo->Proxy->GetLightType() == LightType_Directional &&
		// Only use a stationary or movable light
		!LightSceneInfo->Proxy->HasStaticLighting())
	{
		// Set SimpleDirectionalLight
		if(!SimpleDirectionalLight)
		{
			SimpleDirectionalLight = LightSceneInfo;
		}

		if(GetShadingPath() == EShadingPath::Mobile)
		{
			const bool bUseCSMForDynamicObjects = LightSceneInfo->Proxy->UseCSMForDynamicObjects();
#if !(UE_BUILD_SHIPPING || UE_BUILD_TEST)
			// these are tracked for disabled shader permutation warnings
			if (LightSceneInfo->Proxy->IsMovable())
			{
				NumMobileMovableDirectionalLights_RenderThread++;
			}
			if (bUseCSMForDynamicObjects)
			{
				NumMobileStaticAndCSMLights_RenderThread++;
			}
#endif
		    // Set MobileDirectionalLights entry
		    int32 FirstLightingChannel = GetFirstLightingChannelFromMask(LightSceneInfo->Proxy->GetLightingChannelMask());
		    if (FirstLightingChannel >= 0 && MobileDirectionalLights[FirstLightingChannel] == nullptr)
		    {
			    MobileDirectionalLights[FirstLightingChannel] = LightSceneInfo;
    
			    // if this light is a dynamic shadowcast then we need to update the static draw lists to pick a new lighting policy:
			    if (!LightSceneInfo->Proxy->HasStaticShadowing() || bUseCSMForDynamicObjects)
				{
		    		bScenesPrimitivesNeedStaticMeshElementUpdate = true;
				}
		    }
		}
	}

	const bool bForwardShading = IsForwardShadingEnabled(FeatureLevel);

	if (bForwardShading && LightSceneInfo->Proxy->CastsDynamicShadow())
	{
		if (LightSceneInfo->Proxy->HasStaticShadowing())
		{
			// If we are a stationary light being added, reassign all movable light shadowmap channels
			for (TSparseArray<FLightSceneInfoCompact>::TConstIterator It(Lights); It; ++It)
			{
				const FLightSceneInfoCompact& OtherLightInfo = *It;

				if (OtherLightInfo.LightSceneInfo != LightSceneInfo
					&& !OtherLightInfo.LightSceneInfo->Proxy->HasStaticShadowing()
					&& OtherLightInfo.LightSceneInfo->Proxy->CastsDynamicShadow())
				{
					OtherLightInfo.LightSceneInfo->SetDynamicShadowMapChannel(-1);
				}
			}

			for (TSparseArray<FLightSceneInfoCompact>::TConstIterator It(Lights); It; ++It)
			{
				const FLightSceneInfoCompact& OtherLightInfo = *It;

				if (OtherLightInfo.LightSceneInfo != LightSceneInfo
					&& !OtherLightInfo.LightSceneInfo->Proxy->HasStaticShadowing()
					&& OtherLightInfo.LightSceneInfo->Proxy->CastsDynamicShadow())
				{
					AssignAvailableShadowMapChannelForLight(OtherLightInfo.LightSceneInfo);
				}
			}
		}
		else
		{
			// If we are a movable light being added, assign a shadowmap channel
			AssignAvailableShadowMapChannelForLight(LightSceneInfo);
		}
	}

	if (LightSceneInfo->Proxy->IsUsedAsAtmosphereSunLight() &&
		(!SunLight || LightSceneInfo->Proxy->GetColor().ComputeLuminance() > SunLight->Proxy->GetColor().ComputeLuminance()) ) // choose brightest sun light...
	{
		SunLight = LightSceneInfo;
	}

	// Add the light to the scene.
	LightSceneInfo->AddToScene();
}

void FScene::AddLight(ULightComponent* Light)
{
	// Create the light's scene proxy.
	FLightSceneProxy* Proxy = Light->CreateSceneProxy();
	if(Proxy)
	{
		// Associate the proxy with the light.
		Light->SceneProxy = Proxy;

		// Update the light's transform and position.
		Proxy->SetTransform(Light->ComponentToWorld.ToMatrixNoScale(),Light->GetLightPosition());

		// Create the light scene info.
		Proxy->LightSceneInfo = new FLightSceneInfo(Proxy, true);

		INC_DWORD_STAT(STAT_SceneLights);

		// Adding a new light
		++NumVisibleLights_GameThread;

		// Send a command to the rendering thread to add the light to the scene.
		ENQUEUE_UNIQUE_RENDER_COMMAND_TWOPARAMETER(
			FAddLightCommand,
			FScene*,Scene,this,
			FLightSceneInfo*,LightSceneInfo,Proxy->LightSceneInfo,
			{
				FScopeCycleCounter Context(LightSceneInfo->Proxy->GetStatId());
				Scene->AddLightSceneInfo_RenderThread(LightSceneInfo);
			});
	}
}

void FScene::AddInvisibleLight(ULightComponent* Light)
{
	// Create the light's scene proxy.
	FLightSceneProxy* Proxy = Light->CreateSceneProxy();

	if(Proxy)
	{
		// Associate the proxy with the light.
		Light->SceneProxy = Proxy;

		// Update the light's transform and position.
		Proxy->SetTransform(Light->ComponentToWorld.ToMatrixNoScale(),Light->GetLightPosition());

		// Create the light scene info.
		Proxy->LightSceneInfo = new FLightSceneInfo(Proxy, false);

		INC_DWORD_STAT(STAT_SceneLights);

		// Send a command to the rendering thread to add the light to the scene.
		ENQUEUE_UNIQUE_RENDER_COMMAND_TWOPARAMETER(
			FAddLightCommand,
			FScene*,Scene,this,
			FLightSceneInfo*,LightSceneInfo,Proxy->LightSceneInfo,
		{
			FScopeCycleCounter Context(LightSceneInfo->Proxy->GetStatId());
			LightSceneInfo->Id = Scene->InvisibleLights.Add(FLightSceneInfoCompact(LightSceneInfo));
		});
	}
}

void FScene::SetSkyLight(FSkyLightSceneProxy* LightProxy)
{
	check(LightProxy);
	NumEnabledSkylights_GameThread++;

	// Send a command to the rendering thread to add the light to the scene.
	ENQUEUE_UNIQUE_RENDER_COMMAND_TWOPARAMETER(
		FSetSkyLightCommand,
		FScene*,Scene,this,
		FSkyLightSceneProxy*,LightProxy,LightProxy,
	{
		check(!Scene->SkyLightStack.Contains(LightProxy));
		Scene->SkyLightStack.Push(LightProxy);
		const bool bOriginalHadSkylight = Scene->ShouldRenderSkylightInBasePass(BLEND_Opaque);

		// Use the most recently enabled skylight
		Scene->SkyLight = LightProxy;

		const bool bNewHasSkylight = Scene->ShouldRenderSkylightInBasePass(BLEND_Opaque);

		if (bOriginalHadSkylight != bNewHasSkylight)
		{
			// Mark the scene as needing static draw lists to be recreated if needed
			// The base pass chooses shaders based on whether there's a skylight in the scene, and that is cached in static draw lists
			Scene->bScenesPrimitivesNeedStaticMeshElementUpdate = true;
		}
	});
}

void FScene::DisableSkyLight(FSkyLightSceneProxy* LightProxy)
{
	check(LightProxy);
	NumEnabledSkylights_GameThread--;

	ENQUEUE_UNIQUE_RENDER_COMMAND_TWOPARAMETER(
		FDisableSkyLightCommand,
		FScene*,Scene,this,
		FSkyLightSceneProxy*,LightProxy,LightProxy,
	{
		const bool bOriginalHadSkylight = Scene->ShouldRenderSkylightInBasePass(BLEND_Opaque);

		Scene->SkyLightStack.RemoveSingle(LightProxy);

		if (Scene->SkyLightStack.Num() > 0)
		{
			// Use the most recently enabled skylight
			Scene->SkyLight = Scene->SkyLightStack.Last();
		}
		else
		{
			Scene->SkyLight = NULL;
		}

		const bool bNewHasSkylight = Scene->ShouldRenderSkylightInBasePass(BLEND_Opaque);

		// Update the scene if we switched skylight enabled states
		if (bOriginalHadSkylight != bNewHasSkylight)
		{
			Scene->bScenesPrimitivesNeedStaticMeshElementUpdate = true;
		}
	});
}

void FScene::AddOrRemoveDecal_RenderThread(FDeferredDecalProxy* Proxy, bool bAdd)
{
	if(bAdd)
	{
		Decals.Add(Proxy);
	}
	else
	{
		// can be optimized
		for(TSparseArray<FDeferredDecalProxy*>::TIterator It(Decals); It; ++It)
		{
			FDeferredDecalProxy* CurrentProxy = *It;

			if (CurrentProxy == Proxy)
			{
				It.RemoveCurrent();
				delete CurrentProxy;
				break;
			}
		}
	}
}

void FScene::AddDecal(UDecalComponent* Component)
{
	if(!Component->SceneProxy)
	{
		// Create the decals's scene proxy.
		Component->SceneProxy = Component->CreateSceneProxy();

		INC_DWORD_STAT(STAT_SceneDecals);

		// Send a command to the rendering thread to add the light to the scene.
		ENQUEUE_UNIQUE_RENDER_COMMAND_TWOPARAMETER(
			FAddDecalCommand,
			FScene*,Scene,this,
			FDeferredDecalProxy*,Proxy,Component->SceneProxy,
		{
			Scene->AddOrRemoveDecal_RenderThread(Proxy, true);
		});
	}
}

void FScene::RemoveDecal(UDecalComponent* Component)
{
	if(Component->SceneProxy)
	{
		DEC_DWORD_STAT(STAT_SceneDecals);

		// Send a command to the rendering thread to remove the light from the scene.
		ENQUEUE_UNIQUE_RENDER_COMMAND_TWOPARAMETER(
			FRemoveDecalCommand,
			FScene*,Scene,this,
			FDeferredDecalProxy*,Proxy,Component->SceneProxy,
		{
			Scene->AddOrRemoveDecal_RenderThread(Proxy, false);
		});

		// Disassociate the primitive's scene proxy.
		Component->SceneProxy = NULL;
	}
}

void FScene::UpdateDecalTransform(UDecalComponent* Decal)
{
	if(Decal->SceneProxy)
	{
		//Send command to the rendering thread to update the decal's transform.
		ENQUEUE_UNIQUE_RENDER_COMMAND_TWOPARAMETER(
			UpdateTransformCommand,
			FDeferredDecalProxy*,DecalSceneProxy,Decal->SceneProxy,
			FTransform,ComponentToWorldIncludingDecalSize,Decal->GetTransformIncludingDecalSize(),
		{
			// Update the primitive's transform.
			DecalSceneProxy->SetTransformIncludingDecalSize(ComponentToWorldIncludingDecalSize);
		});
	}
}

void FScene::AddReflectionCapture(UReflectionCaptureComponent* Component)
{
	if (!Component->SceneProxy)
	{
		Component->SceneProxy = Component->CreateSceneProxy();

		ENQUEUE_UNIQUE_RENDER_COMMAND_TWOPARAMETER(
			FAddCaptureCommand,
			FScene*,Scene,this,
			FReflectionCaptureProxy*,Proxy,Component->SceneProxy,
		{
			Scene->ReflectionSceneData.bRegisteredReflectionCapturesHasChanged = true;
			const int32 PackedIndex = Scene->ReflectionSceneData.RegisteredReflectionCaptures.Add(Proxy);

			Proxy->PackedIndex = PackedIndex;
			Scene->ReflectionSceneData.RegisteredReflectionCapturePositions.Add(Proxy->Position);

			checkSlow(Scene->ReflectionSceneData.RegisteredReflectionCaptures.Num() == Scene->ReflectionSceneData.RegisteredReflectionCapturePositions.Num());
		});
	}
}

void FScene::RemoveReflectionCapture(UReflectionCaptureComponent* Component)
{
	if (Component->SceneProxy)
	{
		ENQUEUE_UNIQUE_RENDER_COMMAND_TWOPARAMETER(
			FRemoveCaptureCommand,
			FScene*,Scene,this,
			FReflectionCaptureProxy*,Proxy,Component->SceneProxy,
		{
			Scene->ReflectionSceneData.bRegisteredReflectionCapturesHasChanged = true;

			int32 CaptureIndex = Proxy->PackedIndex;
			Scene->ReflectionSceneData.RegisteredReflectionCaptures.RemoveAtSwap(CaptureIndex);
			Scene->ReflectionSceneData.RegisteredReflectionCapturePositions.RemoveAtSwap(CaptureIndex);

			if (Scene->ReflectionSceneData.RegisteredReflectionCaptures.IsValidIndex(CaptureIndex))
			{
				FReflectionCaptureProxy* OtherCapture = Scene->ReflectionSceneData.RegisteredReflectionCaptures[CaptureIndex];
				OtherCapture->PackedIndex = CaptureIndex;
			}

			delete Proxy;

			checkSlow(Scene->ReflectionSceneData.RegisteredReflectionCaptures.Num() == Scene->ReflectionSceneData.RegisteredReflectionCapturePositions.Num());
		});

		// Disassociate the primitive's scene proxy.
		Component->SceneProxy = NULL;
	}
}

void FScene::UpdateReflectionCaptureTransform(UReflectionCaptureComponent* Component)
{
	if (Component->SceneProxy)
	{
		ENQUEUE_UNIQUE_RENDER_COMMAND_FOURPARAMETER(
			UpdateTransformCommand,
			FReflectionCaptureProxy*,Proxy,Component->SceneProxy,
			FMatrix,Transform,Component->ComponentToWorld.ToMatrixWithScale(),
			const float*,AverageBrightness,Component->GetAverageBrightnessPtr(),
			FScene*,Scene,this,
		{
			Scene->ReflectionSceneData.bRegisteredReflectionCapturesHasChanged = true;
			Proxy->SetTransform(Transform);
			Proxy->InitializeAverageBrightness(*AverageBrightness);
		});
	}
}

void FScene::ReleaseReflectionCubemap(UReflectionCaptureComponent* CaptureComponent)
{
	bool bRemoved = false;
	for (TSparseArray<UReflectionCaptureComponent*>::TIterator It(ReflectionSceneData.AllocatedReflectionCapturesGameThread); It; ++It)
	{
		UReflectionCaptureComponent* CurrentCapture = *It;

		if (CurrentCapture == CaptureComponent)
		{
			It.RemoveCurrent();
			bRemoved = true;
			break;
		}
	}

	if (bRemoved)
	{
		ENQUEUE_UNIQUE_RENDER_COMMAND_TWOPARAMETER(
			RemoveCaptureCommand,
			UReflectionCaptureComponent*, Component, CaptureComponent,
			FScene*, Scene, this,
		{
			const FCaptureComponentSceneState* ComponentStatePtr = Scene->ReflectionSceneData.AllocatedReflectionCaptureState.Find(Component);
			if (ComponentStatePtr)
			{
				// We track removed captures so we can remap them when reallocating the cubemap array
				check(ComponentStatePtr->CaptureIndex != -1);
				Scene->ReflectionSceneData.CubemapArraySlotsUsed[ComponentStatePtr->CaptureIndex] = false;
			}
			Scene->ReflectionSceneData.AllocatedReflectionCaptureState.Remove(Component);
		});
	}
}

const FReflectionCaptureProxy* FScene::FindClosestReflectionCapture(FVector Position) const
{
	checkSlow(IsInParallelRenderingThread());
	int32 ClosestCaptureIndex = INDEX_NONE;
	float ClosestDistanceSquared = FLT_MAX;

	// Linear search through the scene's reflection captures
	// ReflectionSceneData.RegisteredReflectionCapturePositions has been packed densely to make this coherent in memory
	for (int32 CaptureIndex = 0; CaptureIndex < ReflectionSceneData.RegisteredReflectionCapturePositions.Num(); CaptureIndex++)
	{
		const float DistanceSquared = (ReflectionSceneData.RegisteredReflectionCapturePositions[CaptureIndex] - Position).SizeSquared();

		if (DistanceSquared < ClosestDistanceSquared)
		{
			ClosestDistanceSquared = DistanceSquared;
			ClosestCaptureIndex = CaptureIndex;
		}
	}

	return ClosestCaptureIndex != INDEX_NONE ? ReflectionSceneData.RegisteredReflectionCaptures[ClosestCaptureIndex] : NULL;
}

const FPlanarReflectionSceneProxy* FScene::FindClosestPlanarReflection(const FPrimitiveBounds& Bounds) const
{
	checkSlow(IsInParallelRenderingThread());
	const FPlanarReflectionSceneProxy* ClosestPlanarReflection = NULL;
	float ClosestDistance = FLT_MAX;
	FBox PrimitiveBoundingBox(Bounds.Origin - Bounds.BoxExtent, Bounds.Origin + Bounds.BoxExtent);

	// Linear search through the scene's planar reflections
	for (int32 CaptureIndex = 0; CaptureIndex < PlanarReflections.Num(); CaptureIndex++)
	{
		FPlanarReflectionSceneProxy* CurrentPlanarReflection = PlanarReflections[CaptureIndex];
		const FBox ReflectionBounds = CurrentPlanarReflection->WorldBounds;

		if (PrimitiveBoundingBox.Intersect(ReflectionBounds))
		{
			const float Distance = FMath::Abs(CurrentPlanarReflection->ReflectionPlane.PlaneDot(Bounds.Origin));

			if (Distance < ClosestDistance)
			{
				ClosestDistance = Distance;
				ClosestPlanarReflection = CurrentPlanarReflection;
			}
		}
	}

	return ClosestPlanarReflection;
}

void FScene::FindClosestReflectionCaptures(FVector Position, const FReflectionCaptureProxy* (&SortedByDistanceOUT)[FPrimitiveSceneInfo::MaxCachedReflectionCaptureProxies]) const
{
	checkSlow(IsInParallelRenderingThread());
	static const int32 ArraySize = FPrimitiveSceneInfo::MaxCachedReflectionCaptureProxies;

	struct FReflectionCaptureDistIndex
	{
		int32 CaptureIndex;
		float CaptureDistance;
		const FReflectionCaptureProxy* CaptureProxy;
	};

	// Find the nearest n captures to this primitive. 
	const int32 NumRegisteredReflectionCaptures = ReflectionSceneData.RegisteredReflectionCapturePositions.Num();
	const int32 PopulateCaptureCount = FMath::Min(ArraySize, NumRegisteredReflectionCaptures);

	TArray<FReflectionCaptureDistIndex, TFixedAllocator<ArraySize>> ClosestCaptureIndices;
	ClosestCaptureIndices.AddUninitialized(PopulateCaptureCount);

	for (int32 CaptureIndex = 0; CaptureIndex < PopulateCaptureCount; CaptureIndex++)
	{
		ClosestCaptureIndices[CaptureIndex].CaptureIndex = CaptureIndex;
		ClosestCaptureIndices[CaptureIndex].CaptureDistance = (ReflectionSceneData.RegisteredReflectionCapturePositions[CaptureIndex] - Position).SizeSquared();
	}
	
	for (int32 CaptureIndex = PopulateCaptureCount; CaptureIndex < NumRegisteredReflectionCaptures; CaptureIndex++)
	{
		const float DistanceSquared = (ReflectionSceneData.RegisteredReflectionCapturePositions[CaptureIndex] - Position).SizeSquared();
		for (int32 i = 0; i < ArraySize; i++)
		{
			if (DistanceSquared<ClosestCaptureIndices[i].CaptureDistance)
			{
				ClosestCaptureIndices[i].CaptureDistance = DistanceSquared;
				ClosestCaptureIndices[i].CaptureIndex = CaptureIndex;
				break;
			}
		}
	}

	for (int32 CaptureIndex = 0; CaptureIndex < PopulateCaptureCount; CaptureIndex++)
	{
		FReflectionCaptureProxy* CaptureProxy = ReflectionSceneData.RegisteredReflectionCaptures[ClosestCaptureIndices[CaptureIndex].CaptureIndex];		
		ClosestCaptureIndices[CaptureIndex].CaptureProxy = CaptureProxy;
	}
	// Sort by influence radius.
	ClosestCaptureIndices.Sort([](const FReflectionCaptureDistIndex& A, const FReflectionCaptureDistIndex& B)
		{
			if (A.CaptureProxy->InfluenceRadius != B.CaptureProxy->InfluenceRadius)
			{
				return (A.CaptureProxy->InfluenceRadius < B.CaptureProxy->InfluenceRadius);
			}
			return A.CaptureProxy->Guid < B.CaptureProxy->Guid;
		});

	FMemory::Memzero(SortedByDistanceOUT);

	for (int32 CaptureIndex = 0; CaptureIndex < PopulateCaptureCount; CaptureIndex++)
	{
		SortedByDistanceOUT[CaptureIndex] = ClosestCaptureIndices[CaptureIndex].CaptureProxy;
	}
}

void FScene::GetCaptureParameters(const FReflectionCaptureProxy* ReflectionProxy, FTextureRHIParamRef& ReflectionCubemapArray, int32& ArrayIndex) const
{
	ERHIFeatureLevel::Type LocalFeatureLevel = GetFeatureLevel();

	if (LocalFeatureLevel >= ERHIFeatureLevel::SM5)
	{
		const FCaptureComponentSceneState* FoundState = ReflectionSceneData.AllocatedReflectionCaptureState.Find(ReflectionProxy->Component);

		if (FoundState)
		{
			ReflectionCubemapArray = ReflectionSceneData.CubemapArray.GetRenderTarget().ShaderResourceTexture;
			ArrayIndex = FoundState->CaptureIndex;
		}
	}
	else if (ReflectionProxy->SM4FullHDRCubemap)
	{
		ReflectionCubemapArray = ReflectionProxy->SM4FullHDRCubemap->TextureRHI;
		ArrayIndex = 0;
	}
}

int64 FScene::GetCachedWholeSceneShadowMapsSize() const
{
	int64 CachedShadowmapMemory = 0;

	for (TMap<int32, FCachedShadowMapData>::TConstIterator CachedShadowMapIt(CachedShadowMaps); CachedShadowMapIt; ++CachedShadowMapIt)
	{
		const FCachedShadowMapData& ShadowMapData = CachedShadowMapIt.Value();

		if (ShadowMapData.ShadowMap.IsValid())
		{
			CachedShadowmapMemory += ShadowMapData.ShadowMap.ComputeMemorySize();
		}
	}

	return CachedShadowmapMemory;
}

void FScene::AddPrecomputedLightVolume(const FPrecomputedLightVolume* Volume)
{
	FScene* Scene = this;

	ENQUEUE_RENDER_COMMAND(AddVolumeCommand)
		([Scene, Volume](FRHICommandListImmediate& RHICmdList) 
		{
			Scene->PrecomputedLightVolumes.Add(Volume);
			Scene->IndirectLightingCache.SetLightingCacheDirty(Scene, Volume);
		});
}

void FScene::RemovePrecomputedLightVolume(const FPrecomputedLightVolume* Volume)
{
	FScene* Scene = this; 

	ENQUEUE_RENDER_COMMAND(RemoveVolumeCommand)
		([Scene, Volume](FRHICommandListImmediate& RHICmdList) 
		{
			Scene->PrecomputedLightVolumes.Remove(Volume);
			Scene->IndirectLightingCache.SetLightingCacheDirty(Scene, Volume);
		});
}

struct FUpdateLightTransformParameters
{
	FMatrix LightToWorld;
	FVector4 Position;
};

void FScene::UpdateLightTransform_RenderThread(FLightSceneInfo* LightSceneInfo, const FUpdateLightTransformParameters& Parameters)
{
	SCOPE_CYCLE_COUNTER(STAT_UpdateSceneLightTime);
	if( LightSceneInfo && LightSceneInfo->bVisible )
	{
		// Don't remove directional lights when their transform changes as nothing in RemoveFromScene() depends on their transform
		if (!(LightSceneInfo->Proxy->GetLightType() == LightType_Directional))
		{
			// Remove the light from the scene.
			LightSceneInfo->RemoveFromScene();
		}

		// Update the light's transform and position.
		LightSceneInfo->Proxy->SetTransform(Parameters.LightToWorld,Parameters.Position);

		// Also update the LightSceneInfoCompact
		if( LightSceneInfo->Id != INDEX_NONE )
		{
			LightSceneInfo->Scene->Lights[LightSceneInfo->Id].Init(LightSceneInfo);

			// Don't re-add directional lights when their transform changes as nothing in AddToScene() depends on their transform
			if (!(LightSceneInfo->Proxy->GetLightType() == LightType_Directional))
			{
				// Add the light to the scene at its new location.
				LightSceneInfo->AddToScene();
			}
		}
	}
}

void FScene::UpdateLightTransform(ULightComponent* Light)
{
	if(Light->SceneProxy)
	{
		FUpdateLightTransformParameters Parameters;
		Parameters.LightToWorld = Light->ComponentToWorld.ToMatrixNoScale();
		Parameters.Position = Light->GetLightPosition();
		ENQUEUE_UNIQUE_RENDER_COMMAND_THREEPARAMETER(
			UpdateLightTransform,
			FScene*,Scene,this,
			FLightSceneInfo*,LightSceneInfo,Light->SceneProxy->GetLightSceneInfo(),
			FUpdateLightTransformParameters,Parameters,Parameters,
			{
				FScopeCycleCounter Context(LightSceneInfo->Proxy->GetStatId());
				Scene->UpdateLightTransform_RenderThread(LightSceneInfo, Parameters);
			});
	}
}

/** 
 * Updates the color and brightness of a light which has already been added to the scene. 
 *
 * @param Light - light component to update
 */
void FScene::UpdateLightColorAndBrightness(ULightComponent* Light)
{
	if(Light->SceneProxy)
	{
		struct FUpdateLightColorParameters
		{
			FLinearColor NewColor;
			float NewIndirectLightingScale;
			float NewVolumetricScatteringIntensity;
		};

		FUpdateLightColorParameters NewParameters;
		NewParameters.NewColor = FLinearColor(Light->LightColor) * Light->ComputeLightBrightness();
		NewParameters.NewIndirectLightingScale = Light->IndirectLightingIntensity;
		NewParameters.NewVolumetricScatteringIntensity = Light->VolumetricScatteringIntensity;

		if( Light->bUseTemperature )
		{
			 NewParameters.NewColor *= FLinearColor::MakeFromColorTemperature(Light->Temperature);
		}
	
		ENQUEUE_UNIQUE_RENDER_COMMAND_THREEPARAMETER(
			UpdateLightColorAndBrightness,
			FLightSceneInfo*,LightSceneInfo,Light->SceneProxy->GetLightSceneInfo(),
			FScene*,Scene,this,
			FUpdateLightColorParameters,Parameters,NewParameters,
			{
				if( LightSceneInfo && LightSceneInfo->bVisible )
				{
					// Mobile renderer:
					// a light with no color/intensity can cause the light to be ignored when rendering.
					// thus, lights that change state in this way must update the draw lists.
					Scene->bScenesPrimitivesNeedStaticMeshElementUpdate =
						Scene->bScenesPrimitivesNeedStaticMeshElementUpdate ||
						( Scene->GetShadingPath() == EShadingPath::Mobile 
						&& Parameters.NewColor.IsAlmostBlack() != LightSceneInfo->Proxy->GetColor().IsAlmostBlack() );

					LightSceneInfo->Proxy->SetColor(Parameters.NewColor);
					LightSceneInfo->Proxy->IndirectLightingScale = Parameters.NewIndirectLightingScale;
					LightSceneInfo->Proxy->VolumetricScatteringIntensity = Parameters.NewVolumetricScatteringIntensity;

					// Also update the LightSceneInfoCompact
					if( LightSceneInfo->Id != INDEX_NONE )
					{
						Scene->Lights[ LightSceneInfo->Id ].Color = Parameters.NewColor;
					}
				}
			});
	}
}

void FScene::RemoveLightSceneInfo_RenderThread(FLightSceneInfo* LightSceneInfo)
{
	SCOPE_CYCLE_COUNTER(STAT_RemoveSceneLightTime);

	if (LightSceneInfo->bVisible)
	{
		// check SimpleDirectionalLight
		if (LightSceneInfo == SimpleDirectionalLight)
		{
			SimpleDirectionalLight = nullptr;
		}

		if(GetShadingPath() == EShadingPath::Mobile)
		{
			const bool bUseCSMForDynamicObjects = LightSceneInfo->Proxy->UseCSMForDynamicObjects();

#if !(UE_BUILD_SHIPPING || UE_BUILD_TEST)
			// Tracked for disabled shader permutation warnings.
			// Condition must match that in AddLightSceneInfo_RenderThread
			if (LightSceneInfo->Proxy->GetLightType() == LightType_Directional && !LightSceneInfo->Proxy->HasStaticLighting())
			{
				if (LightSceneInfo->Proxy->IsMovable())
				{
					NumMobileMovableDirectionalLights_RenderThread--;
				}
				if (bUseCSMForDynamicObjects)
				{
					NumMobileStaticAndCSMLights_RenderThread--;
				}
			}
#endif

			// check MobileDirectionalLights
		    for (int32 LightChannelIdx = 0; LightChannelIdx < ARRAY_COUNT(MobileDirectionalLights); LightChannelIdx++)
		    {
			    if (LightSceneInfo == MobileDirectionalLights[LightChannelIdx])
			    {
				    MobileDirectionalLights[LightChannelIdx] = nullptr;
					// if this light is a dynamic shadowcast then we need to update the static draw lists to pick a new lightingpolicy
					if (!LightSceneInfo->Proxy->HasStaticShadowing() || bUseCSMForDynamicObjects)
					{
						bScenesPrimitivesNeedStaticMeshElementUpdate = true;
					}
				    break;
			    }
		    }
		}

		if (LightSceneInfo == SunLight)
		{
			SunLight = NULL;
			// Search for new sun light...
			for (TSparseArray<FLightSceneInfoCompact>::TConstIterator It(Lights); It; ++It)
			{
				const FLightSceneInfoCompact& LightInfo = *It;
				if (LightInfo.LightSceneInfo != LightSceneInfo
					&& LightInfo.LightSceneInfo->Proxy->bUsedAsAtmosphereSunLight
					&& (!SunLight || SunLight->Proxy->GetColor().ComputeLuminance() < LightInfo.LightSceneInfo->Proxy->GetColor().ComputeLuminance()) )
				{
					SunLight = LightInfo.LightSceneInfo;
				}
			}
		}

		// Remove the light from the scene.
		LightSceneInfo->RemoveFromScene();

		// Remove the light from the lights list.
		Lights.RemoveAt(LightSceneInfo->Id);

		if (!LightSceneInfo->Proxy->HasStaticShadowing()
			&& LightSceneInfo->Proxy->CastsDynamicShadow()
			&& LightSceneInfo->GetDynamicShadowMapChannel() == -1)
		{
			OverflowingDynamicShadowedLights.Remove(LightSceneInfo->Proxy->GetComponentName());
		}
	}
	else
	{
		InvisibleLights.RemoveAt(LightSceneInfo->Id);
	}

	// Free the light scene info and proxy.
	delete LightSceneInfo->Proxy;
	delete LightSceneInfo;
}

void FScene::RemoveLight(ULightComponent* Light)
{
	if(Light->SceneProxy)
	{
		FLightSceneInfo* LightSceneInfo = Light->SceneProxy->GetLightSceneInfo();

		DEC_DWORD_STAT(STAT_SceneLights);

		// Removing one visible light
		--NumVisibleLights_GameThread;

		// Disassociate the primitive's render info.
		Light->SceneProxy = NULL;

		// Send a command to the rendering thread to remove the light from the scene.
		ENQUEUE_UNIQUE_RENDER_COMMAND_TWOPARAMETER(
			FRemoveLightCommand,
			FScene*,Scene,this,
			FLightSceneInfo*,LightSceneInfo,LightSceneInfo,
			{
				FScopeCycleCounter Context(LightSceneInfo->Proxy->GetStatId());
				Scene->RemoveLightSceneInfo_RenderThread(LightSceneInfo);
			});
	}
}

void FScene::AddExponentialHeightFog(UExponentialHeightFogComponent* FogComponent)
{
	ENQUEUE_UNIQUE_RENDER_COMMAND_TWOPARAMETER(
		FAddFogCommand,
		FScene*,Scene,this,
		FExponentialHeightFogSceneInfo,HeightFogSceneInfo,FExponentialHeightFogSceneInfo(FogComponent),
		{
			// Create a FExponentialHeightFogSceneInfo for the component in the scene's fog array.
			new(Scene->ExponentialFogs) FExponentialHeightFogSceneInfo(HeightFogSceneInfo);
		});
}

void FScene::RemoveExponentialHeightFog(UExponentialHeightFogComponent* FogComponent)
{
	ENQUEUE_UNIQUE_RENDER_COMMAND_TWOPARAMETER(
		FRemoveFogCommand,
		FScene*,Scene,this,
		UExponentialHeightFogComponent*,FogComponent,FogComponent,
		{
			// Remove the given component's FExponentialHeightFogSceneInfo from the scene's fog array.
			for(int32 FogIndex = 0;FogIndex < Scene->ExponentialFogs.Num();FogIndex++)
			{
				if(Scene->ExponentialFogs[FogIndex].Component == FogComponent)
				{
					Scene->ExponentialFogs.RemoveAt(FogIndex);
					break;
				}
			}
		});
}

void FScene::AddWindSource(UWindDirectionalSourceComponent* WindComponent)
{
	// if this wind component is not activated (or Auto Active is set to false), then don't add to WindSources
	if(!WindComponent->IsActive())
	{
		return;
	}

	WindComponents_GameThread.Add(WindComponent);

	FWindSourceSceneProxy* SceneProxy = WindComponent->CreateSceneProxy();
	WindComponent->SceneProxy = SceneProxy;

	ENQUEUE_UNIQUE_RENDER_COMMAND_TWOPARAMETER(
		FAddWindSourceCommand,
		FScene*,Scene,this,
		FWindSourceSceneProxy*,SceneProxy,SceneProxy,
		{
			Scene->WindSources.Add(SceneProxy);
		});
}

void FScene::RemoveWindSource(UWindDirectionalSourceComponent* WindComponent)
{
	WindComponents_GameThread.Remove(WindComponent);

	FWindSourceSceneProxy* SceneProxy = WindComponent->SceneProxy;
	WindComponent->SceneProxy = NULL;

	if(SceneProxy)
	{
		ENQUEUE_UNIQUE_RENDER_COMMAND_TWOPARAMETER(
			FRemoveWindSourceCommand,
			FScene*,Scene,this,
			FWindSourceSceneProxy*,SceneProxy,SceneProxy,
			{
				Scene->WindSources.Remove(SceneProxy);

				delete SceneProxy;
			});
	}
}

const TArray<FWindSourceSceneProxy*>& FScene::GetWindSources_RenderThread() const
{
	checkSlow(IsInRenderingThread());
	return WindSources;
}

void FScene::GetWindParameters(const FVector& Position, FVector& OutDirection, float& OutSpeed, float& OutMinGustAmt, float& OutMaxGustAmt) const
{
	FWindData AccumWindData;
	AccumWindData.PrepareForAccumulate();

	int32 NumActiveWindSources = 0;
	FVector4 AccumulatedDirectionAndSpeed(0,0,0,0);
	float TotalWeight = 0.0f;
	for (int32 i = 0; i < WindSources.Num(); i++)
	{
		
		FVector4 CurrentDirectionAndSpeed;
		float Weight;
		const FWindSourceSceneProxy* CurrentSource = WindSources[i];
		FWindData CurrentSourceData;
		if (CurrentSource->GetWindParameters(Position, CurrentSourceData, Weight))
		{
			AccumWindData.AddWeighted(CurrentSourceData, Weight);
			TotalWeight += Weight;
			NumActiveWindSources++;
		}
	}

	AccumWindData.NormalizeByTotalWeight(TotalWeight);

	if (NumActiveWindSources == 0)
	{
		AccumWindData.Direction = FVector(1.0f, 0.0f, 0.0f);
	}
	OutDirection	= AccumWindData.Direction;
	OutSpeed		= AccumWindData.Speed;
	OutMinGustAmt	= AccumWindData.MinGustAmt;
	OutMaxGustAmt	= AccumWindData.MaxGustAmt;
}

void FScene::GetWindParameters_GameThread(const FVector& Position, FVector& OutDirection, float& OutSpeed, float& OutMinGustAmt, float& OutMaxGustAmt) const
{
	FWindData AccumWindData;
	AccumWindData.PrepareForAccumulate();

	const int32 NumSources = WindComponents_GameThread.Num();
	int32 NumActiveSources = 0;
	float TotalWeight = 0.0f;

	// read the wind component array, this is safe for the game thread
	for(UWindDirectionalSourceComponent* Component : WindComponents_GameThread)
	{
		float Weight = 0.0f;
		FWindData CurrentComponentData;
		if(Component->GetWindParameters(Position, CurrentComponentData, Weight))
		{
			AccumWindData.AddWeighted(CurrentComponentData, Weight);
			TotalWeight += Weight;
			++NumActiveSources;
		}
	}

	AccumWindData.NormalizeByTotalWeight(TotalWeight);

	if(NumActiveSources == 0)
	{
		AccumWindData.Direction = FVector(1.0f, 0.0f, 0.0f);
	}

	OutDirection = AccumWindData.Direction;
	OutSpeed = AccumWindData.Speed;
	OutMinGustAmt = AccumWindData.MinGustAmt;
	OutMaxGustAmt = AccumWindData.MaxGustAmt;
}

void FScene::GetDirectionalWindParameters(FVector& OutDirection, float& OutSpeed, float& OutMinGustAmt, float& OutMaxGustAmt) const
{
	FWindData AccumWindData;
	AccumWindData.PrepareForAccumulate();

	int32 NumActiveWindSources = 0;
	FVector4 AccumulatedDirectionAndSpeed(0,0,0,0);
	float TotalWeight = 0.0f;
	for (int32 i = 0; i < WindSources.Num(); i++)
	{
		FVector4 CurrentDirectionAndSpeed;
		float Weight;
		const FWindSourceSceneProxy* CurrentSource = WindSources[i];
		FWindData CurrentSourceData;
		if (CurrentSource->GetDirectionalWindParameters(CurrentSourceData, Weight))
		{
			AccumWindData.AddWeighted(CurrentSourceData, Weight);			
			TotalWeight += Weight;
			NumActiveWindSources++;
		}
	}

	AccumWindData.NormalizeByTotalWeight(TotalWeight);	

	if (NumActiveWindSources == 0)
	{
		AccumWindData.Direction = FVector(1.0f, 0.0f, 0.0f);
	}
	OutDirection = AccumWindData.Direction;
	OutSpeed = AccumWindData.Speed;
	OutMinGustAmt = AccumWindData.MinGustAmt;
	OutMaxGustAmt = AccumWindData.MaxGustAmt;
}

void FScene::AddSpeedTreeWind(FVertexFactory* VertexFactory, const UStaticMesh* StaticMesh)
{
	if (StaticMesh != NULL && StaticMesh->SpeedTreeWind.IsValid() && StaticMesh->RenderData.IsValid())
	{
		ENQUEUE_UNIQUE_RENDER_COMMAND_THREEPARAMETER(
			FAddSpeedTreeWindCommand,
			FScene*,Scene,this,
			const UStaticMesh*,StaticMesh,StaticMesh,
			FVertexFactory*,VertexFactory,VertexFactory,
			{
				Scene->SpeedTreeVertexFactoryMap.Add(VertexFactory, StaticMesh);

				if (Scene->SpeedTreeWindComputationMap.Contains(StaticMesh))
				{
					(*(Scene->SpeedTreeWindComputationMap.Find(StaticMesh)))->ReferenceCount++;
				}
				else
				{
					FSpeedTreeWindComputation* WindComputation = new FSpeedTreeWindComputation;
					WindComputation->Wind = *(StaticMesh->SpeedTreeWind.Get( ));
					WindComputation->UniformBuffer.SetContentsToZero();
					WindComputation->UniformBuffer.InitResource();
					Scene->SpeedTreeWindComputationMap.Add(StaticMesh, WindComputation);
				}
			});
	}
}

void FScene::RemoveSpeedTreeWind(class FVertexFactory* VertexFactory, const class UStaticMesh* StaticMesh)
{
	if (StaticMesh != NULL && StaticMesh->SpeedTreeWind.IsValid() && StaticMesh->RenderData.IsValid())
	{
		ENQUEUE_UNIQUE_RENDER_COMMAND_THREEPARAMETER(
			FRemoveSpeedTreeWindCommand,
			FScene*,Scene,this,
			const UStaticMesh*, StaticMesh, StaticMesh,
			FVertexFactory*,VertexFactory,VertexFactory,
			{
				Scene->RemoveSpeedTreeWind_RenderThread(VertexFactory, StaticMesh);
			});
	}
}

void FScene::RemoveSpeedTreeWind_RenderThread(class FVertexFactory* VertexFactory, const class UStaticMesh* StaticMesh)
{
	FSpeedTreeWindComputation** WindComputationRef = SpeedTreeWindComputationMap.Find(StaticMesh);
	if (WindComputationRef != NULL)
	{
		FSpeedTreeWindComputation* WindComputation = *WindComputationRef;

		WindComputation->ReferenceCount--;
		if (WindComputation->ReferenceCount < 1)
		{
			for (auto Iter = SpeedTreeVertexFactoryMap.CreateIterator(); Iter; ++Iter )
			{
				if (Iter.Value() == StaticMesh)
				{
					Iter.RemoveCurrent();
				}
			}

			SpeedTreeWindComputationMap.Remove(StaticMesh);
			WindComputation->UniformBuffer.ReleaseResource();
			delete WindComputation;
		}
	}
}

void FScene::UpdateSpeedTreeWind(double CurrentTime)
{
#define SET_SPEEDTREE_TABLE_FLOAT4V(name, offset) \
	UniformParameters.name = *(FVector4*)(WindShaderValues + FSpeedTreeWind::offset); \
	UniformParameters.Prev##name = *(FVector4*)(WindShaderValues + FSpeedTreeWind::offset + FSpeedTreeWind::NUM_SHADER_VALUES);

	FScene* Scene = this;
	ENQUEUE_RENDER_COMMAND(FUpdateSpeedTreeWindCommand)(
		[Scene, CurrentTime](FRHICommandListImmediate& RHICmdList)
		{
			FVector WindDirection;
			float WindSpeed;
			float WindMinGustAmt;
			float WindMaxGustAmt;
			Scene->GetDirectionalWindParameters(WindDirection, WindSpeed, WindMinGustAmt, WindMaxGustAmt);

			for (TMap<const UStaticMesh*, FSpeedTreeWindComputation*>::TIterator It(Scene->SpeedTreeWindComputationMap); It; ++It )
			{
				const UStaticMesh* StaticMesh = It.Key();
				FSpeedTreeWindComputation* WindComputation = It.Value();

				if( !(StaticMesh->RenderData.IsValid() && StaticMesh->SpeedTreeWind.IsValid()) )
				{
					It.RemoveCurrent();
					continue;
				}

				if (GIsEditor && StaticMesh->SpeedTreeWind->NeedsReload( ))
				{
					// reload the wind since it may have changed or been scaled differently during reimport
					StaticMesh->SpeedTreeWind->SetNeedsReload(false);
					WindComputation->Wind = *(StaticMesh->SpeedTreeWind.Get( ));

					// make sure the vertex factories are registered (sometimes goes wrong during a reimport)
					for (int32 LODIndex = 0; LODIndex < StaticMesh->RenderData->LODResources.Num(); ++LODIndex)
					{
						Scene->SpeedTreeVertexFactoryMap.Add(&StaticMesh->RenderData->LODResources[LODIndex].VertexFactory, StaticMesh);
						Scene->SpeedTreeVertexFactoryMap.Add(&StaticMesh->RenderData->LODResources[LODIndex].VertexFactoryOverrideColorVertexBuffer, StaticMesh);
					}
				}

				// advance the wind object
				WindComputation->Wind.SetDirection(WindDirection);
				WindComputation->Wind.SetStrength(WindSpeed);
				WindComputation->Wind.SetGustMin(WindMinGustAmt);
				WindComputation->Wind.SetGustMax(WindMaxGustAmt);
				WindComputation->Wind.Advance(true, CurrentTime);

				// copy data into uniform buffer
				const float* WindShaderValues = WindComputation->Wind.GetShaderTable();

				FSpeedTreeUniformParameters UniformParameters;
				UniformParameters.WindAnimation.Set(CurrentTime, 0.0f, 0.0f, 0.0f);
			
				SET_SPEEDTREE_TABLE_FLOAT4V(WindVector, SH_WIND_DIR_X);
				SET_SPEEDTREE_TABLE_FLOAT4V(WindGlobal, SH_GLOBAL_TIME);
				SET_SPEEDTREE_TABLE_FLOAT4V(WindBranch, SH_BRANCH_1_TIME);
				SET_SPEEDTREE_TABLE_FLOAT4V(WindBranchTwitch, SH_BRANCH_1_TWITCH);
				SET_SPEEDTREE_TABLE_FLOAT4V(WindBranchWhip, SH_BRANCH_1_WHIP);
				SET_SPEEDTREE_TABLE_FLOAT4V(WindBranchAnchor, SH_WIND_ANCHOR_X);
				SET_SPEEDTREE_TABLE_FLOAT4V(WindBranchAdherences, SH_GLOBAL_DIRECTION_ADHERENCE);
				SET_SPEEDTREE_TABLE_FLOAT4V(WindTurbulences, SH_BRANCH_1_TURBULENCE);
				SET_SPEEDTREE_TABLE_FLOAT4V(WindLeaf1Ripple, SH_LEAF_1_RIPPLE_TIME);
				SET_SPEEDTREE_TABLE_FLOAT4V(WindLeaf1Tumble, SH_LEAF_1_TUMBLE_TIME);
				SET_SPEEDTREE_TABLE_FLOAT4V(WindLeaf1Twitch, SH_LEAF_1_TWITCH_THROW);
				SET_SPEEDTREE_TABLE_FLOAT4V(WindLeaf2Ripple, SH_LEAF_2_RIPPLE_TIME);
				SET_SPEEDTREE_TABLE_FLOAT4V(WindLeaf2Tumble, SH_LEAF_2_TUMBLE_TIME);
				SET_SPEEDTREE_TABLE_FLOAT4V(WindLeaf2Twitch, SH_LEAF_2_TWITCH_THROW);
				SET_SPEEDTREE_TABLE_FLOAT4V(WindFrondRipple, SH_FROND_RIPPLE_TIME);
				SET_SPEEDTREE_TABLE_FLOAT4V(WindRollingBranch, SH_ROLLING_BRANCH_FIELD_MIN);
				SET_SPEEDTREE_TABLE_FLOAT4V(WindRollingLeafAndDirection, SH_ROLLING_LEAF_RIPPLE_MIN);
				SET_SPEEDTREE_TABLE_FLOAT4V(WindRollingNoise, SH_ROLLING_NOISE_PERIOD);

				WindComputation->UniformBuffer.SetContents(UniformParameters);
			}
		});
	#undef SET_SPEEDTREE_TABLE_FLOAT4V
}

FUniformBufferRHIParamRef FScene::GetSpeedTreeUniformBuffer(const FVertexFactory* VertexFactory)
{
	if (VertexFactory != NULL)
	{
		const UStaticMesh** StaticMesh = SpeedTreeVertexFactoryMap.Find(VertexFactory);
		if (StaticMesh != NULL)
		{
			FSpeedTreeWindComputation** WindComputation = SpeedTreeWindComputationMap.Find(*StaticMesh);
			if (WindComputation != NULL)
			{
				return (*WindComputation)->UniformBuffer.GetUniformBufferRHI();
			}
		}
	}

	return FUniformBufferRHIParamRef();
}

/**
 * Retrieves the lights interacting with the passed in primitive and adds them to the out array.
 *
 * Render thread version of function.
 * 
 * @param	Primitive				Primitive to retrieve interacting lights for
 * @param	RelevantLights	[out]	Array of lights interacting with primitive
 */
void FScene::GetRelevantLights_RenderThread( UPrimitiveComponent* Primitive, TArray<const ULightComponent*>* RelevantLights ) const
{
	check( Primitive );
	check( RelevantLights );
	if( Primitive->SceneProxy )
	{
		for( const FLightPrimitiveInteraction* Interaction=Primitive->SceneProxy->GetPrimitiveSceneInfo()->LightList; Interaction; Interaction=Interaction->GetNextLight() )
		{
			RelevantLights->Add( Interaction->GetLight()->Proxy->GetLightComponent() );
		}
	}
}

/**
 * Retrieves the lights interacting with the passed in primitive and adds them to the out array.
 *
 * @param	Primitive				Primitive to retrieve interacting lights for
 * @param	RelevantLights	[out]	Array of lights interacting with primitive
 */
void FScene::GetRelevantLights( UPrimitiveComponent* Primitive, TArray<const ULightComponent*>* RelevantLights ) const
{
	if( Primitive && RelevantLights )
	{
		// Add interacting lights to the array.
		ENQUEUE_UNIQUE_RENDER_COMMAND_THREEPARAMETER(
			FGetRelevantLightsCommand,
			const FScene*,Scene,this,
			UPrimitiveComponent*,Primitive,Primitive,
			TArray<const ULightComponent*>*,RelevantLights,RelevantLights,
			{
				Scene->GetRelevantLights_RenderThread( Primitive, RelevantLights );
			});

		// We need to block the main thread as the rendering thread needs to finish modifying the array before we can continue.
		FlushRenderingCommands();
	}
}

/** Sets the precomputed visibility handler for the scene, or NULL to clear the current one. */
void FScene::SetPrecomputedVisibility(const FPrecomputedVisibilityHandler* NewPrecomputedVisibilityHandler)
{
	ENQUEUE_UNIQUE_RENDER_COMMAND_TWOPARAMETER(
		UpdatePrecomputedVisibility,
		FScene*,Scene,this,
		const FPrecomputedVisibilityHandler*,PrecomputedVisibilityHandler,NewPrecomputedVisibilityHandler,
	{
		Scene->PrecomputedVisibilityHandler = PrecomputedVisibilityHandler;
	});
}

void FScene::SetShaderMapsOnMaterialResources_RenderThread(FRHICommandListImmediate& RHICmdList, const FMaterialsToUpdateMap& MaterialsToUpdate)
{
	SCOPE_CYCLE_COUNTER(STAT_Scene_SetShaderMapsOnMaterialResources_RT);

	TArray<const FMaterial*> MaterialArray;

	for (FMaterialsToUpdateMap::TConstIterator It(MaterialsToUpdate); It; ++It)
	{
		FMaterial* Material = It.Key();
		FMaterialShaderMap* ShaderMap = It.Value();
		Material->SetRenderingThreadShaderMap(ShaderMap);
		check(!ShaderMap || ShaderMap->IsValidForRendering());
		MaterialArray.Add(Material);
	}

	const auto SceneFeatureLevel = GetFeatureLevel();
	bool bFoundAnyInitializedMaterials = false;

	// Iterate through all loaded material render proxies and recache their uniform expressions if needed
	// This search does not scale well, but is only used when uploading async shader compile results
	for (TSet<FMaterialRenderProxy*>::TConstIterator It(FMaterialRenderProxy::GetMaterialRenderProxyMap()); It; ++It)
	{
		FMaterialRenderProxy* MaterialProxy = *It;
		FMaterial* Material = MaterialProxy->GetMaterialNoFallback(SceneFeatureLevel);

		if (Material && MaterialsToUpdate.Contains(Material))
		{
			// Materials used as async fallbacks can't be updated through this mechanism and should have been updated synchronously earlier
			check(!Material->RequiresSynchronousCompilation());
			MaterialProxy->CacheUniformExpressions();
			bFoundAnyInitializedMaterials = true;

			const FMaterial& MaterialForRendering = *MaterialProxy->GetMaterial(SceneFeatureLevel);
			check(MaterialForRendering.GetRenderingThreadShaderMap());

			check(!MaterialProxy->UniformExpressionCache[SceneFeatureLevel].bUpToDate
				|| MaterialProxy->UniformExpressionCache[SceneFeatureLevel].CachedUniformExpressionShaderMap == MaterialForRendering.GetRenderingThreadShaderMap());

			check(MaterialForRendering.GetRenderingThreadShaderMap()->IsValidForRendering());
		}
	}
}

void FScene::SetShaderMapsOnMaterialResources(const TMap<FMaterial*, class FMaterialShaderMap*>& MaterialsToUpdate)
{
	for (TMap<FMaterial*, FMaterialShaderMap*>::TConstIterator It(MaterialsToUpdate); It; ++It)
	{
		FMaterial* Material = It.Key();
		check(!Material->RequiresSynchronousCompilation());
	}

	ENQUEUE_UNIQUE_RENDER_COMMAND_TWOPARAMETER(
		FSetShaderMapOnMaterialResources,
		FScene*,Scene,this,
		FMaterialsToUpdateMap,MaterialsToUpdate,MaterialsToUpdate,
	{
		Scene->SetShaderMapsOnMaterialResources_RenderThread(RHICmdList, MaterialsToUpdate);
	});
}

void FScene::UpdateStaticDrawListsForMaterials_RenderThread(FRHICommandListImmediate& RHICmdList, const TArray<const FMaterial*>& Materials)
{
	SCOPE_CYCLE_COUNTER(STAT_Scene_UpdateStaticDrawListsForMaterials_RT);

	// Warning: if any static draw lists are missed here, there will be a crash when trying to render with shaders that have been deleted!
	TArray<FPrimitiveSceneInfo*> PrimitivesToUpdate;
	auto SceneFeatureLevel = GetFeatureLevel();

	if (GetShadingPath() == EShadingPath::Deferred)
	{
		for (int32 DrawType = 0; DrawType < EBasePass_MAX; DrawType++)
		{
			BasePassSelfShadowedTranslucencyDrawList[DrawType].GetUsedPrimitivesBasedOnMaterials(SceneFeatureLevel, Materials, PrimitivesToUpdate);
			BasePassSelfShadowedCachedPointIndirectTranslucencyDrawList[DrawType].GetUsedPrimitivesBasedOnMaterials(SceneFeatureLevel, Materials, PrimitivesToUpdate);

			BasePassUniformLightMapPolicyDrawList[DrawType].GetUsedPrimitivesBasedOnMaterials(SceneFeatureLevel, Materials, PrimitivesToUpdate);
		}
	}
	else if (GetShadingPath() == EShadingPath::Mobile)
	{
		for (int32 DrawType = 0; DrawType < EBasePass_MAX; DrawType++)
		{
			MobileBasePassUniformLightMapPolicyDrawList[DrawType].GetUsedPrimitivesBasedOnMaterials(SceneFeatureLevel, Materials, PrimitivesToUpdate);
			MobileBasePassUniformLightMapPolicyDrawListWithCSM[DrawType].GetUsedPrimitivesBasedOnMaterials(SceneFeatureLevel, Materials, PrimitivesToUpdate);
		}
	}

	PositionOnlyDepthDrawList.GetUsedPrimitivesBasedOnMaterials(SceneFeatureLevel, Materials, PrimitivesToUpdate);
	DepthDrawList.GetUsedPrimitivesBasedOnMaterials(SceneFeatureLevel, Materials, PrimitivesToUpdate);
	MaskedDepthDrawList.GetUsedPrimitivesBasedOnMaterials(SceneFeatureLevel, Materials, PrimitivesToUpdate);
	HitProxyDrawList.GetUsedPrimitivesBasedOnMaterials(SceneFeatureLevel, Materials, PrimitivesToUpdate);
	HitProxyDrawList_OpaqueOnly.GetUsedPrimitivesBasedOnMaterials(SceneFeatureLevel, Materials, PrimitivesToUpdate);
#if WITH_EDITOR
	EditorSelectionDrawList.GetUsedPrimitivesBasedOnMaterials(SceneFeatureLevel, Materials, PrimitivesToUpdate);
#endif
	VelocityDrawList.GetUsedPrimitivesBasedOnMaterials(SceneFeatureLevel, Materials, PrimitivesToUpdate);
	WholeSceneShadowDepthDrawList.GetUsedPrimitivesBasedOnMaterials(SceneFeatureLevel, Materials, PrimitivesToUpdate);
	WholeSceneReflectiveShadowMapDrawList.GetUsedPrimitivesBasedOnMaterials(SceneFeatureLevel, Materials, PrimitivesToUpdate);

	for (int32 PrimitiveIndex = 0; PrimitiveIndex < PrimitivesToUpdate.Num(); PrimitiveIndex++)
	{
		FPrimitiveSceneInfo* Primitive = PrimitivesToUpdate[PrimitiveIndex];

		Primitive->RemoveStaticMeshes();
		Primitive->AddStaticMeshes(RHICmdList);
	}
}

void FScene::UpdateStaticDrawListsForMaterials(const TArray<const FMaterial*>& Materials)
{
	ENQUEUE_UNIQUE_RENDER_COMMAND_TWOPARAMETER(
		FUpdateDrawLists,
		FScene*,Scene,this,
		TArray<const FMaterial*>,Materials,Materials,
	{
		Scene->UpdateStaticDrawListsForMaterials_RenderThread(RHICmdList, Materials);
	});
}

/**
 * @return		true if hit proxies should be rendered in this scene.
 */
bool FScene::RequiresHitProxies() const
{
	return (GIsEditor && bRequiresHitProxies);
}

void FScene::Release()
{
#if !(UE_BUILD_SHIPPING || UE_BUILD_TEST)
	// Verify that no components reference this scene being destroyed
	static bool bTriggeredOnce = false;

	if (!bTriggeredOnce)
	{
		for (auto* ActorComponent : TObjectRange<UActorComponent>())
		{
			if ( !ensureMsgf(!ActorComponent->IsRegistered() || ActorComponent->GetScene() != this, 
					*FString::Printf(TEXT("Component Name: %s World Name: %s Component Asset: %s"), 
										*ActorComponent->GetFullName(), 
										*GetWorld()->GetFullName(), 
										*ActorComponent->AdditionalStatObject()->GetPathName())) )
			{
				bTriggeredOnce = true;
				break;
			}
		}
	}
#endif

	GetRendererModule().RemoveScene(this);

	// Send a command to the rendering thread to release the scene.
	ENQUEUE_UNIQUE_RENDER_COMMAND_ONEPARAMETER(
		FReleaseCommand,
		FScene*,Scene,this,
		{
			delete Scene;
		});
}

void FScene::ConditionalMarkStaticMeshElementsForUpdate()
{
	static auto* EarlyZPassCvar = IConsoleManager::Get().FindTConsoleVariableDataInt(TEXT("r.EarlyZPass"));
	static auto* ShaderPipelinesCvar = IConsoleManager::Get().FindTConsoleVariableDataInt(TEXT("r.ShaderPipelines"));

	bool bMobileHDR = IsMobileHDR();
	bool bMobileHDR32bpp = IsMobileHDR32bpp();
	int32 DesiredStaticDrawListsEarlyZPassMode = EarlyZPassCvar->GetValueOnRenderThread();
	int32 DesiredStaticDrawShaderPipelines = ShaderPipelinesCvar->GetValueOnRenderThread();

	if (bScenesPrimitivesNeedStaticMeshElementUpdate
		|| bStaticDrawListsMobileHDR != bMobileHDR
		|| bStaticDrawListsMobileHDR32bpp != bMobileHDR32bpp
		|| StaticDrawShaderPipelines != DesiredStaticDrawShaderPipelines
		|| StaticDrawListsEarlyZPassMode != DesiredStaticDrawListsEarlyZPassMode)
	{
		// Mark all primitives as needing an update
		// Note: Only visible primitives will actually update their static mesh elements
		for (int32 PrimitiveIndex = 0; PrimitiveIndex < Primitives.Num(); PrimitiveIndex++)
		{
			Primitives[PrimitiveIndex]->BeginDeferredUpdateStaticMeshes();
		}

		bScenesPrimitivesNeedStaticMeshElementUpdate = false;
		bStaticDrawListsMobileHDR = bMobileHDR;
		bStaticDrawListsMobileHDR32bpp = bMobileHDR32bpp;
		StaticDrawListsEarlyZPassMode = DesiredStaticDrawListsEarlyZPassMode;
		StaticDrawShaderPipelines = DesiredStaticDrawShaderPipelines;
	}
}

void FScene::DumpUnbuiltLightIteractions( FOutputDevice& Ar ) const
{
	FlushRenderingCommands();

	TArray<FString> LightsWithUnbuiltInteractions;
	TArray<FString> PrimitivesWithUnbuiltInteractions;

	// if want to print out all of the lights
	for( TSparseArray<FLightSceneInfoCompact>::TConstIterator It(Lights); It; ++It )
	{
		const FLightSceneInfoCompact& LightCompactInfo = *It;
		FLightSceneInfo* LightSceneInfo = LightCompactInfo.LightSceneInfo;

		bool bLightHasUnbuiltInteractions = false;

		for(FLightPrimitiveInteraction* Interaction = LightSceneInfo->DynamicInteractionOftenMovingPrimitiveList;
			Interaction;
			Interaction = Interaction->GetNextPrimitive())
		{
			if (Interaction->IsUncachedStaticLighting())
			{
				bLightHasUnbuiltInteractions = true;
				PrimitivesWithUnbuiltInteractions.AddUnique(Interaction->GetPrimitiveSceneInfo()->ComponentForDebuggingOnly->GetFullName());
			}
		}

		for(FLightPrimitiveInteraction* Interaction = LightSceneInfo->DynamicInteractionStaticPrimitiveList;
			Interaction;
			Interaction = Interaction->GetNextPrimitive())
		{
			if (Interaction->IsUncachedStaticLighting())
			{
				bLightHasUnbuiltInteractions = true;
				PrimitivesWithUnbuiltInteractions.AddUnique(Interaction->GetPrimitiveSceneInfo()->ComponentForDebuggingOnly->GetFullName());
			}
		}

		if (bLightHasUnbuiltInteractions)
		{
			LightsWithUnbuiltInteractions.AddUnique(LightSceneInfo->Proxy->GetComponentName().ToString());
		}
	}

	Ar.Logf( TEXT( "DumpUnbuiltLightIteractions" ) );
	Ar.Logf( TEXT( "Lights with unbuilt interactions: %d" ), LightsWithUnbuiltInteractions.Num() );
	for (int Index = 0; Index < LightsWithUnbuiltInteractions.Num(); Index++)
	{
		Ar.Logf(TEXT("    Light %s"), *LightsWithUnbuiltInteractions[Index]);
	}

	Ar.Logf( TEXT( "" ) );
	Ar.Logf( TEXT( "Primitives with unbuilt interactions: %d" ), PrimitivesWithUnbuiltInteractions.Num() );
	for (int Index = 0; Index < PrimitivesWithUnbuiltInteractions.Num(); Index++)
	{
		Ar.Logf(TEXT("    Primitive %s"), *PrimitivesWithUnbuiltInteractions[Index]);
	}
}

/**
 * Logs the provided draw list stats.
 */
static void LogDrawListStats(FDrawListStats Stats, const TCHAR* DrawListName)
{
	if (Stats.NumDrawingPolicies == 0 || Stats.NumMeshes == 0)
	{
		UE_LOG(LogRenderer,Log,TEXT("%s: empty"), DrawListName);
	}
	else
	{
		FString MatchFailedReasons;
		for (auto& It : Stats.SingleMeshPolicyMatchFailedReasons)
		{
			TArray<FStringFormatArg> Args;
			Args.Emplace(It.Value);
			Args.Emplace(*It.Key);

			MatchFailedReasons.Append(FString::Format(TEXT("      - {0} ({1})\n"), Args));
		}

		FString VertexFactoryFreq;
		for (auto& It : Stats.SingleMeshPolicyVertexFactoryFrequency)
		{
			TArray<FStringFormatArg> Args;
			auto KeyStr = It.Key.ToString();

			Args.Emplace(It.Value);
			Args.Emplace(*KeyStr);

			VertexFactoryFreq.Append(FString::Format(TEXT("      - {0} ({1})\n"), Args));
		}

		UE_LOG(LogRenderer,Log,
			TEXT("%s: %d policies %d meshes\n")
			TEXT("  - %d median meshes/policy\n")
			TEXT("  - %f mean meshes/policy\n")
			TEXT("  - %d max meshes/policy\n")
			TEXT("  - %d policies with one mesh\n")
			TEXT("    One mesh policy closest match failure reason:\n%s\n")
			TEXT("    One mesh policy vertex factory frequencies:\n%s"),
			DrawListName,
			Stats.NumDrawingPolicies,
			Stats.NumMeshes,
			Stats.MedianMeshesPerDrawingPolicy,
			(float)Stats.NumMeshes / (float)Stats.NumDrawingPolicies,
			Stats.MaxMeshesPerDrawingPolicy,
			Stats.NumSingleMeshDrawingPolicies,
			*MatchFailedReasons,
			*VertexFactoryFreq
			);
	}
}

void FScene::DumpStaticMeshDrawListStats() const
{
	UE_LOG(LogRenderer,Log,TEXT("Static mesh draw lists for %s:"),
		World ? *World->GetFullName() : TEXT("[no world]")
		);
#define DUMP_DRAW_LIST(Name) LogDrawListStats(Name.GetStats(), TEXT(#Name))
	DUMP_DRAW_LIST(PositionOnlyDepthDrawList);
	DUMP_DRAW_LIST(DepthDrawList);
	DUMP_DRAW_LIST(MaskedDepthDrawList);
	DUMP_DRAW_LIST(BasePassSelfShadowedTranslucencyDrawList[EBasePass_Default]);
	DUMP_DRAW_LIST(BasePassSelfShadowedTranslucencyDrawList[EBasePass_Masked]);
	DUMP_DRAW_LIST(BasePassSelfShadowedCachedPointIndirectTranslucencyDrawList[EBasePass_Default]);
	DUMP_DRAW_LIST(BasePassSelfShadowedCachedPointIndirectTranslucencyDrawList[EBasePass_Masked]);
	DUMP_DRAW_LIST(BasePassUniformLightMapPolicyDrawList[EBasePass_Default]);
	DUMP_DRAW_LIST(BasePassUniformLightMapPolicyDrawList[EBasePass_Masked]);
	DUMP_DRAW_LIST(MobileBasePassUniformLightMapPolicyDrawList[EBasePass_Default]);
	DUMP_DRAW_LIST(MobileBasePassUniformLightMapPolicyDrawList[EBasePass_Masked]);
	DUMP_DRAW_LIST(MobileBasePassUniformLightMapPolicyDrawListWithCSM[EBasePass_Default]);
	DUMP_DRAW_LIST(MobileBasePassUniformLightMapPolicyDrawListWithCSM[EBasePass_Masked]);
	DUMP_DRAW_LIST(HitProxyDrawList);
	DUMP_DRAW_LIST(HitProxyDrawList_OpaqueOnly);
#if WITH_EDITOR
	DUMP_DRAW_LIST(EditorSelectionDrawList);
#endif
	DUMP_DRAW_LIST(VelocityDrawList);
	DUMP_DRAW_LIST(WholeSceneShadowDepthDrawList);
#undef DUMP_DRAW_LIST
}

/**
 * Dumps stats for all scenes to the log.
 */
static void DumpDrawListStats()
{
	for (TObjectIterator<UWorld> It; It; ++It)
	{
		UWorld* World = *It;
		if (World && World->Scene)
		{
			World->Scene->DumpStaticMeshDrawListStats();
		}
	}
}

static FAutoConsoleCommand GDumpDrawListStatsCmd(
	TEXT("r.DumpDrawListStats"),
	TEXT("Dumps static mesh draw list statistics for all scenes associated with ")
	TEXT("world objects."),
	FConsoleCommandDelegate::CreateStatic(&DumpDrawListStats)
	);

/**
 * Exports the scene.
 *
 * @param	Ar		The Archive used for exporting.
 **/
void FScene::Export( FArchive& Ar ) const
{
	
}

void FScene::ApplyWorldOffset(FVector InOffset)
{
	// Send a command to the rendering thread to shift scene data
	ENQUEUE_UNIQUE_RENDER_COMMAND_TWOPARAMETER(
		FApplyWorldOffset,
		FScene*,Scene,this,
		FVector,InOffset,InOffset,
	{
		Scene->ApplyWorldOffset_RenderThread(InOffset);
	});
}

// StaticMeshDrawList elements shifting
template<typename T>
static void StaticMeshDrawListApplyWorldOffset(T& InList, FVector InOffset)
{
	InList.ApplyWorldOffset(InOffset);
}

// StaticMeshDrawList elements shifting: specialization for an arrays
template<typename T, int32 N>
static void StaticMeshDrawListApplyWorldOffset(T(&InList)[N], FVector InOffset)
{
	for (int32 i = 0; i < N; i++)
	{
		InList[i].ApplyWorldOffset(InOffset);
	}
}

void FScene::ApplyWorldOffset_RenderThread(FVector InOffset)
{
	QUICK_SCOPE_CYCLE_COUNTER(STAT_SceneApplyWorldOffset);
	
	// Primitives
	for (auto It = Primitives.CreateIterator(); It; ++It)
	{
		(*It)->ApplyWorldOffset(InOffset);
	}

	// Precomputed light volumes
	for (const FPrecomputedLightVolume* It : PrecomputedLightVolumes)
	{
		const_cast<FPrecomputedLightVolume*>(It)->ApplyWorldOffset(InOffset);
	}

	// Precomputed visibility
	if (PrecomputedVisibilityHandler)
	{
		const_cast<FPrecomputedVisibilityHandler*>(PrecomputedVisibilityHandler)->ApplyWorldOffset(InOffset);
	}
	
	// Invalidate indirect lighting cache
	IndirectLightingCache.SetLightingCacheDirty(this, NULL);

	// Primitives octree
	PrimitiveOctree.ApplyOffset(InOffset, /*bGlobalOctee*/ true);

	// Primitive bounds
	for (auto It = PrimitiveBounds.CreateIterator(); It; ++It)
	{
		(*It).Origin+= InOffset;
	}

	// Primitive occlusion bounds
	for (auto It = PrimitiveOcclusionBounds.CreateIterator(); It; ++It)
	{
		(*It).Origin+= InOffset;
	}

	// Lights
	VectorRegister OffsetReg = VectorLoadFloat3_W0(&InOffset);
	for (auto It = Lights.CreateIterator(); It; ++It)
	{
		(*It).BoundingSphereVector = VectorAdd((*It).BoundingSphereVector, OffsetReg);
		(*It).LightSceneInfo->Proxy->ApplyWorldOffset(InOffset);
	}

	// Lights octree
	LightOctree.ApplyOffset(InOffset, /*bGlobalOctee*/ true);

	// Cached preshadows
	for (auto It = CachedPreshadows.CreateIterator(); It; ++It)
	{
		(*It)->PreShadowTranslation-= InOffset;
		(*It)->ShadowBounds.Center+= InOffset;
	}

	// Decals
	for (auto It = Decals.CreateIterator(); It; ++It)
	{
		(*It)->ComponentTrans.AddToTranslation(InOffset);
	}

	// Wind sources
	for (auto It = WindSources.CreateIterator(); It; ++It)
	{
		(*It)->ApplyWorldOffset(InOffset);
	}

	// Reflection captures
	for (auto It = ReflectionSceneData.RegisteredReflectionCaptures.CreateIterator(); It; ++It)
	{
		FMatrix NewTransform = (*It)->BoxTransform.Inverse().ConcatTranslation(InOffset);
		(*It)->SetTransform(NewTransform);
	}

	// Exponential Fog
	for (FExponentialHeightFogSceneInfo& FogInfo : ExponentialFogs)
	{
		FogInfo.FogHeight+= InOffset.Z;
	}
	
	// StaticMeshDrawLists
	StaticMeshDrawListApplyWorldOffset(PositionOnlyDepthDrawList, InOffset);
	StaticMeshDrawListApplyWorldOffset(DepthDrawList, InOffset);
	StaticMeshDrawListApplyWorldOffset(MaskedDepthDrawList, InOffset);
	StaticMeshDrawListApplyWorldOffset(BasePassSelfShadowedTranslucencyDrawList, InOffset);
	StaticMeshDrawListApplyWorldOffset(BasePassSelfShadowedCachedPointIndirectTranslucencyDrawList, InOffset);
	StaticMeshDrawListApplyWorldOffset(BasePassUniformLightMapPolicyDrawList, InOffset);
	StaticMeshDrawListApplyWorldOffset(HitProxyDrawList, InOffset);
	StaticMeshDrawListApplyWorldOffset(HitProxyDrawList_OpaqueOnly, InOffset);
	StaticMeshDrawListApplyWorldOffset(VelocityDrawList, InOffset);
	StaticMeshDrawListApplyWorldOffset(WholeSceneShadowDepthDrawList, InOffset);
	StaticMeshDrawListApplyWorldOffset(MobileBasePassUniformLightMapPolicyDrawList, InOffset);
	StaticMeshDrawListApplyWorldOffset(MobileBasePassUniformLightMapPolicyDrawListWithCSM, InOffset);

	// Motion blur 
	MotionBlurInfoData.ApplyOffset(InOffset);
}

void FScene::OnLevelAddedToWorld(FName LevelAddedName, UWorld* InWorld, bool bIsLightingScenario)
{
	if (bIsLightingScenario)
	{
		InWorld->PropagateLightingScenarioChange();
	}

	ENQUEUE_UNIQUE_RENDER_COMMAND_TWOPARAMETER(
		FLevelAddedToWorld,
		class FScene*, Scene, this,
		FName, LevelName, LevelAddedName,
	{
		Scene->OnLevelAddedToWorld_RenderThread(LevelName);
	});
}

void FScene::OnLevelAddedToWorld_RenderThread(FName InLevelName)
{
	// Mark level primitives
	for (auto It = Primitives.CreateIterator(); It; ++It)
	{
		FPrimitiveSceneProxy* Proxy = (*It)->Proxy;
		if (Proxy->LevelName == InLevelName)
		{
			Proxy->bIsComponentLevelVisible = true;
			if (Proxy->NeedsLevelAddedToWorldNotification())
			{
				Proxy->OnLevelAddedToWorld();
			}
		}
	}
}

void FScene::OnLevelRemovedFromWorld(UWorld* InWorld, bool bIsLightingScenario)
{
	if (bIsLightingScenario)
	{
		InWorld->PropagateLightingScenarioChange();
	}
}

#if WITH_EDITOR
bool FScene::InitializePixelInspector(FRenderTarget* BufferFinalColor, FRenderTarget* BufferSceneColor, FRenderTarget* BufferDepth, FRenderTarget* BufferHDR, FRenderTarget* BufferA, FRenderTarget* BufferBCDE, int32 BufferIndex)
{
	//Initialize the buffers
	PixelInspectorData.InitializeBuffers(BufferFinalColor, BufferSceneColor, BufferDepth, BufferHDR, BufferA, BufferBCDE, BufferIndex);
	//return true when the interface is implemented
	return true;
}

bool FScene::AddPixelInspectorRequest(FPixelInspectorRequest *PixelInspectorRequest)
{
	return PixelInspectorData.AddPixelInspectorRequest(PixelInspectorRequest);
}
#endif //WITH_EDITOR

/**
 * Dummy NULL scene interface used by dedicated servers.
 */
class FNULLSceneInterface : public FSceneInterface
{
public:
	FNULLSceneInterface(UWorld* InWorld, bool bCreateFXSystem )
		:	World( InWorld )
		,	FXSystem( NULL )
	{
		World->Scene = this;

		if (bCreateFXSystem)
		{
			World->CreateFXSystem();
		}
		else
		{
			World->FXSystem = NULL;
			SetFXSystem(NULL);
		}
	}

	virtual void AddPrimitive(UPrimitiveComponent* Primitive) override {}
	virtual void RemovePrimitive(UPrimitiveComponent* Primitive) override {}
	virtual void ReleasePrimitive(UPrimitiveComponent* Primitive) override {}
	virtual FPrimitiveSceneInfo* GetPrimitiveSceneInfo(int32 PrimiteIndex) override { return NULL; }

	/** Updates the transform of a primitive which has already been added to the scene. */
	virtual void UpdatePrimitiveTransform(UPrimitiveComponent* Primitive) override {}
	virtual void UpdatePrimitiveAttachment(UPrimitiveComponent* Primitive) override {}

	virtual void AddLight(ULightComponent* Light) override {}
	virtual void RemoveLight(ULightComponent* Light) override {}
	virtual void AddInvisibleLight(ULightComponent* Light) override {}
	virtual void SetSkyLight(FSkyLightSceneProxy* Light) override {}
	virtual void DisableSkyLight(FSkyLightSceneProxy* Light) override {}

	virtual void AddDecal(UDecalComponent*) override {}
	virtual void RemoveDecal(UDecalComponent*) override {}
	virtual void UpdateDecalTransform(UDecalComponent* Decal) override {}

	/** Updates the transform of a light which has already been added to the scene. */
	virtual void UpdateLightTransform(ULightComponent* Light) override {}
	virtual void UpdateLightColorAndBrightness(ULightComponent* Light) override {}

	virtual void AddExponentialHeightFog(class UExponentialHeightFogComponent* FogComponent) override {}
	virtual void RemoveExponentialHeightFog(class UExponentialHeightFogComponent* FogComponent) override {}
	virtual void AddAtmosphericFog(class UAtmosphericFogComponent* FogComponent) override {}
	virtual void RemoveAtmosphericFog(class UAtmosphericFogComponent* FogComponent) override {}
	virtual void RemoveAtmosphericFogResource_RenderThread(FRenderResource* FogResource) override {}
	virtual FAtmosphericFogSceneInfo* GetAtmosphericFogSceneInfo() override { return NULL; }
	virtual void AddWindSource(class UWindDirectionalSourceComponent* WindComponent) override {}
	virtual void RemoveWindSource(class UWindDirectionalSourceComponent* WindComponent) override {}
	virtual const TArray<class FWindSourceSceneProxy*>& GetWindSources_RenderThread() const override
	{
		static TArray<class FWindSourceSceneProxy*> NullWindSources;
		return NullWindSources;
	}
	virtual void GetWindParameters(const FVector& Position, FVector& OutDirection, float& OutSpeed, float& OutMinGustAmt, float& OutMaxGustAmt) const override { OutDirection = FVector(1.0f, 0.0f, 0.0f); OutSpeed = 0.0f; OutMinGustAmt = 0.0f; OutMaxGustAmt = 0.0f; }
	virtual void GetWindParameters_GameThread(const FVector& Position, FVector& OutDirection, float& OutSpeed, float& OutMinGustAmt, float& OutMaxGustAmt) const override { OutDirection = FVector(1.0f, 0.0f, 0.0f); OutSpeed = 0.0f; OutMinGustAmt = 0.0f; OutMaxGustAmt = 0.0f; }
	virtual void GetDirectionalWindParameters(FVector& OutDirection, float& OutSpeed, float& OutMinGustAmt, float& OutMaxGustAmt) const override { OutDirection = FVector(1.0f, 0.0f, 0.0f); OutSpeed = 0.0f; OutMinGustAmt = 0.0f; OutMaxGustAmt = 0.0f; }
	virtual void AddSpeedTreeWind(class FVertexFactory* VertexFactory, const class UStaticMesh* StaticMesh) override {}
	virtual void RemoveSpeedTreeWind(class FVertexFactory* VertexFactory, const class UStaticMesh* StaticMesh) override {}
	virtual void RemoveSpeedTreeWind_RenderThread(class FVertexFactory* VertexFactory, const class UStaticMesh* StaticMesh) override {}
	virtual void UpdateSpeedTreeWind(double CurrentTime) override {}
	virtual FUniformBufferRHIParamRef GetSpeedTreeUniformBuffer(const FVertexFactory* VertexFactory) override { return FUniformBufferRHIParamRef(); }

	virtual void Release() override {}

	/**
	 * Retrieves the lights interacting with the passed in primitive and adds them to the out array.
	 *
	 * @param	Primitive				Primitive to retrieve interacting lights for
	 * @param	RelevantLights	[out]	Array of lights interacting with primitive
	 */
	virtual void GetRelevantLights( UPrimitiveComponent* Primitive, TArray<const ULightComponent*>* RelevantLights ) const override {}

	/**
	 * @return		true if hit proxies should be rendered in this scene.
	 */
	virtual bool RequiresHitProxies() const override
	{
		return false;
	}

	// Accessors.
	virtual class UWorld* GetWorld() const override
	{
		return World;
	}

	/**
	* Return the scene to be used for rendering
	*/
	virtual class FScene* GetRenderScene() override
	{
		return NULL;
	}

	/**
	 * Sets the FX system associated with the scene.
	 */
	virtual void SetFXSystem( class FFXSystemInterface* InFXSystem ) override
	{
		FXSystem = InFXSystem;
	}

	/**
	 * Get the FX system associated with the scene.
	 */
	virtual class FFXSystemInterface* GetFXSystem() override
	{
		return FXSystem;
	}

	virtual bool HasAnyLights() const override { return false; }
private:
	UWorld* World;
	class FFXSystemInterface* FXSystem;
};

FSceneInterface* FRendererModule::AllocateScene(UWorld* World, bool bInRequiresHitProxies, bool bCreateFXSystem, ERHIFeatureLevel::Type InFeatureLevel)
{
	check(IsInGameThread());

	// Create a full fledged scene if we have something to render.
	if (GIsClient && FApp::CanEverRender() && !GUsingNullRHI)
	{
		FScene* NewScene = new FScene(World, bInRequiresHitProxies, GIsEditor && (!World || !World->IsGameWorld()), bCreateFXSystem, InFeatureLevel);
		AllocatedScenes.Add(NewScene);
		return NewScene;
	}
	// And fall back to a dummy/ NULL implementation for commandlets and dedicated server.
	else
	{
		return new FNULLSceneInterface(World, bCreateFXSystem);
	}
}

void FRendererModule::RemoveScene(FSceneInterface* Scene)
{
	check(IsInGameThread());
	AllocatedScenes.Remove(Scene);
}

void FRendererModule::UpdateStaticDrawListsForMaterials(const TArray<const FMaterial*>& Materials)
{
	for (TSet<FSceneInterface*>::TConstIterator SceneIt(AllocatedScenes); SceneIt; ++SceneIt)
	{
		(*SceneIt)->UpdateStaticDrawListsForMaterials(Materials);
	}
}

FSceneViewStateInterface* FRendererModule::AllocateViewState()
{
	return new FSceneViewState();
}

/**  */
template<>
TStaticMeshDrawList<TBasePassDrawingPolicy<FSelfShadowedTranslucencyPolicy> >& FScene::GetBasePassDrawList<FSelfShadowedTranslucencyPolicy>(EBasePassDrawListType DrawType)
{
	return BasePassSelfShadowedTranslucencyDrawList[DrawType];
}

/**  */
template<>
TStaticMeshDrawList<TBasePassDrawingPolicy<FSelfShadowedCachedPointIndirectLightingPolicy> >& FScene::GetBasePassDrawList<FSelfShadowedCachedPointIndirectLightingPolicy>(EBasePassDrawListType DrawType)
{
	return BasePassSelfShadowedCachedPointIndirectTranslucencyDrawList[DrawType];
}

/**  */
template<>
TStaticMeshDrawList<TBasePassDrawingPolicy<FUniformLightMapPolicy> >& FScene::GetBasePassDrawList<FUniformLightMapPolicy>(EBasePassDrawListType DrawType)
{
	return BasePassUniformLightMapPolicyDrawList[DrawType];
}

template<>
TStaticMeshDrawList<TMobileBasePassDrawingPolicy<FUniformLightMapPolicy, 0> >& FScene::GetMobileBasePassDrawList<FUniformLightMapPolicy>(EBasePassDrawListType DrawType)
{
	return MobileBasePassUniformLightMapPolicyDrawList[DrawType];
}

template<>
TStaticMeshDrawList<TMobileBasePassDrawingPolicy<FUniformLightMapPolicy, 0> >& FScene::GetMobileBasePassCSMDrawList<FUniformLightMapPolicy>(EBasePassDrawListType DrawType)
{
	return MobileBasePassUniformLightMapPolicyDrawListWithCSM[DrawType];
}

/*-----------------------------------------------------------------------------
	MotionBlurInfoData
-----------------------------------------------------------------------------*/

FMotionBlurInfoData::FMotionBlurInfoData()
	: bShouldClearMotionBlurInfo(false)
	, bWorldIsPaused(false)
{
}

void FMotionBlurInfoData::UpdatePrimitiveMotionBlur(FPrimitiveSceneInfo* PrimitiveSceneInfo)
{
	check(PrimitiveSceneInfo && IsInRenderingThread());

	const FPrimitiveSceneProxy* Proxy = PrimitiveSceneInfo->Proxy; 
	FPrimitiveComponentId ComponentId = PrimitiveSceneInfo->PrimitiveComponentId;

	if (Proxy != NULL && ComponentId.IsValid() && Proxy->IsMovable())
	{
		FMotionBlurInfo* MotionBlurInfo = FindMBInfoIndex(ComponentId);

		if(MotionBlurInfo)
		{
			if(!MotionBlurInfo->GetPrimitiveSceneInfo())
			{
				MotionBlurInfo->SetPrimitiveSceneInfo(PrimitiveSceneInfo);
			}
		}
		else
		{
			// add to the end
			MotionBlurInfo = &MotionBlurInfos.Add(ComponentId, FMotionBlurInfo(ComponentId, PrimitiveSceneInfo));
		}

		//request that this primitive scene info caches its transform at the end of the frame
		MotionBlurInfo->SetKeepAndUpdateThisFrame();
	}
}

void FMotionBlurInfoData::RemovePrimitiveMotionBlur(FPrimitiveSceneInfo* PrimitiveSceneInfo)
{
	check(PrimitiveSceneInfo && IsInRenderingThread());

	const FPrimitiveSceneProxy* Proxy = PrimitiveSceneInfo->Proxy; 

	if (Proxy != NULL && PrimitiveSceneInfo->PrimitiveComponentId.IsValid() && Proxy->IsMovable())
	{
		FMotionBlurInfo* MotionBlurInfo = FindMBInfoIndex(PrimitiveSceneInfo->PrimitiveComponentId);

		if(MotionBlurInfo)
		{ 
			// in case someone called SetKeepAndUpdateThisFrame() before
			MotionBlurInfo->SetKeepAndUpdateThisFrame(false);
			MotionBlurInfo->SetPrimitiveSceneInfo(0);
		}
	}
}

void FMotionBlurInfo::UpdateMotionBlurInfo()
{
	if(MBPrimitiveSceneInfo && MBPrimitiveSceneInfo->Proxy)
	{
		// only if the proxy is still there
		CurrentLocalToWorld = MBPrimitiveSceneInfo->Proxy->GetLocalToWorld();
	}

	bKeepAndUpdateThisFrame = false;
}

// Doxygen has trouble parsing these functions because the header declaring them is in Engine, not Renderer
#if !UE_BUILD_DOCS

void FMotionBlurInfoData::StartFrame(bool bInWorldIsPaused)
{
	bWorldIsPaused = bInWorldIsPaused;

	if(!bWorldIsPaused)
	{
		for (TMap<FPrimitiveComponentId, FMotionBlurInfo>::TIterator It(MotionBlurInfos); It; ++It)
		{
			FMotionBlurInfo& MotionBlurInfo = It.Value();

			MotionBlurInfo.OnStartFrame();
		}
	}
}

void FMotionBlurInfoData::UpdateMotionBlurCache(FScene* InScene)
{
	check(InScene && IsInRenderingThread());

	if(bWorldIsPaused)
	{
		return;
	}

	if (InScene->GetFeatureLevel() >= ERHIFeatureLevel::SM4)
	{
		if(bShouldClearMotionBlurInfo)
		{
			// Clear the motion blur information for this frame.		
			MotionBlurInfos.Empty();
			bShouldClearMotionBlurInfo = false;
		}
		else
		{
			for (TMap<FPrimitiveComponentId, FMotionBlurInfo>::TIterator It(MotionBlurInfos); It; ++It)
			{
				FMotionBlurInfo& MotionBlurInfo = It.Value();

				if (MotionBlurInfo.GetKeepAndUpdateThisFrame())
				{
					MotionBlurInfo.UpdateMotionBlurInfo();
				}
				else
				{
					It.RemoveCurrent();
				}
			}
		}
	}
}

void FMotionBlurInfoData::SetClearMotionBlurInfo()
{
	bShouldClearMotionBlurInfo = true;
}

void FMotionBlurInfoData::ApplyOffset(FVector InOffset)
{
	for (auto It = MotionBlurInfos.CreateIterator(); It; ++It)
	{
		It.Value().ApplyOffset(InOffset);
	}
}

FString FMotionBlurInfoData::GetDebugString() const
{
	return FString::Printf(TEXT("Num=%d Clear=%d"), MotionBlurInfos.Num(), bShouldClearMotionBlurInfo);
}

const FMotionBlurInfo* FMotionBlurInfoData::FindMBInfoIndex(FPrimitiveComponentId ComponentId) const
{
	return MotionBlurInfos.Find(ComponentId);
}

FMotionBlurInfo* FMotionBlurInfoData::FindMBInfoIndex(FPrimitiveComponentId ComponentId)
{
	return MotionBlurInfos.Find(ComponentId);
}

bool FMotionBlurInfoData::GetPrimitiveMotionBlurInfo(const FPrimitiveSceneInfo* PrimitiveSceneInfo, FMatrix& OutPreviousLocalToWorld)
{
	check(IsInParallelRenderingThread());

	if (PrimitiveSceneInfo && PrimitiveSceneInfo->PrimitiveComponentId.IsValid())
	{
		FMotionBlurInfo* MotionBlurInfo = FindMBInfoIndex(PrimitiveSceneInfo->PrimitiveComponentId);

		if(MotionBlurInfo)
		{
			OutPreviousLocalToWorld = MotionBlurInfo->GetPreviousLocalToWorld();
			return true;
		}
	}
	return false;
}

bool FMotionBlurInfoData::GetPrimitiveMotionBlurInfo(const FPrimitiveSceneInfo* PrimitiveSceneInfo, FMatrix& OutPreviousLocalToWorld) const
{
	check(IsInParallelRenderingThread());

	if (PrimitiveSceneInfo && PrimitiveSceneInfo->PrimitiveComponentId.IsValid())
	{
		const FMotionBlurInfo* MotionBlurInfo = FindMBInfoIndex(PrimitiveSceneInfo->PrimitiveComponentId);

		if (MotionBlurInfo)
		{
			OutPreviousLocalToWorld = MotionBlurInfo->GetPreviousLocalToWorld();
			return true;
		}
	}
	return false;
}

//////////////////////////////////////////////////////////////////////////

FLatentGPUTimer::FLatentGPUTimer(int32 InAvgSamples)
: AvgSamples(InAvgSamples)
, TotalTime(0.0f)
, SampleIndex(0)
, QueryIndex(0)
{
	TimeSamples.AddZeroed(AvgSamples);
}

bool FLatentGPUTimer::Tick(FRHICommandListImmediate& RHICmdList)
{
	if (GSupportsTimestampRenderQueries == false)
	{
		return false;
	}

	QueryIndex = (QueryIndex + 1) % NumBufferedFrames;

	if (StartQueries[QueryIndex] && EndQueries[QueryIndex])
	{
		if (GRHIThread)
		{
			// Block until the RHI thread has processed the previous query commands, if necessary
			// Stat disabled since we buffer 2 frames minimum, it won't actually block
			//SCOPE_CYCLE_COUNTER(STAT_TranslucencyTimestampQueryFence_Wait);
			int32 BlockFrame = NumBufferedFrames - 1;
			FRHICommandListExecutor::WaitOnRHIThreadFence(QuerySubmittedFences[BlockFrame]);
			QuerySubmittedFences[BlockFrame] = nullptr;
		}

		uint64 StartMicroseconds;
		uint64 EndMicroseconds;
		bool bStartSuccess;
		bool bEndSuccess;

		{
			// Block on the GPU until we have the timestamp query results, if necessary
			// Stat disabled since we buffer 2 frames minimum, it won't actually block
			//SCOPE_CYCLE_COUNTER(STAT_TranslucencyTimestampQuery_Wait);
			bStartSuccess = RHICmdList.GetRenderQueryResult(StartQueries[QueryIndex], StartMicroseconds, true);
			bEndSuccess = RHICmdList.GetRenderQueryResult(EndQueries[QueryIndex], EndMicroseconds, true);
		}

		TotalTime -= TimeSamples[SampleIndex];
		float LastFrameTranslucencyDurationMS = TimeSamples[SampleIndex];
		if (bStartSuccess && bEndSuccess)
		{
			LastFrameTranslucencyDurationMS = (EndMicroseconds - StartMicroseconds) / 1000.0f;
		}

		TimeSamples[SampleIndex] = LastFrameTranslucencyDurationMS;
		TotalTime += LastFrameTranslucencyDurationMS;
		SampleIndex = (SampleIndex + 1) % AvgSamples;

		return bStartSuccess && bEndSuccess;
	}

	return false;
}

void FLatentGPUTimer::Begin(FRHICommandListImmediate& RHICmdList)
{
	if (GSupportsTimestampRenderQueries == false)
	{
		return;
	}
	
	if (!StartQueries[QueryIndex])
	{
		StartQueries[QueryIndex] = RHICmdList.CreateRenderQuery(RQT_AbsoluteTime);
	}

	RHICmdList.EndRenderQuery(StartQueries[QueryIndex]);
}

void FLatentGPUTimer::End(FRHICommandListImmediate& RHICmdList)
{
	if (GSupportsTimestampRenderQueries == false)
	{
		return;
	}
	
	if (!EndQueries[QueryIndex])
	{
		EndQueries[QueryIndex] = RHICmdList.CreateRenderQuery(RQT_AbsoluteTime);
	}

	RHICmdList.EndRenderQuery(EndQueries[QueryIndex]);
	// Hint to the RHI to submit commands up to this point to the GPU if possible.  Can help avoid CPU stalls next frame waiting
	// for these query results on some platforms.
	RHICmdList.SubmitCommandsHint();

	if (GRHIThread)
	{
		int32 NumFrames = NumBufferedFrames;
		for (int32 Dest = 1; Dest < NumFrames; Dest++)
		{
			QuerySubmittedFences[Dest] = QuerySubmittedFences[Dest - 1];
		}
		// Start an RHI thread fence so we can be sure the RHI thread has processed the EndRenderQuery before we ask for results
		QuerySubmittedFences[0] = RHICmdList.RHIThreadFence();
		RHICmdList.ImmediateFlush(EImmediateFlushType::DispatchToRHIThread);
	}
}

void FLatentGPUTimer::Release()
{
	for (int32 i = 0; i < NumBufferedFrames; ++i)
	{
		StartQueries[i].SafeRelease();
		EndQueries[i].SafeRelease();
	}
}

float FLatentGPUTimer::GetTimeMS()
{
	return TimeSamples[SampleIndex];
}

float FLatentGPUTimer::GetAverageTimeMS()
{
	return TotalTime / AvgSamples;
}


#endif