UnrealEngine/Engine/Source/Runtime/Renderer/Private/SceneVisibility.cpp

// Copyright Epic Games, Inc. All Rights Reserved.

#include "SceneVisibility.h"
#include "SceneVisibilityPrivate.h"
#include "CoreMinimal.h"
#include "ComputeWorkerInterface.h"
#include "HAL/ThreadSafeCounter.h"
#include "Stats/Stats.h"
#include "Misc/MemStack.h"
#include "HAL/IConsoleManager.h"
#include "Misc/App.h"
#include "EngineDefines.h"
#include "EngineGlobals.h"
#include "EngineStats.h"
#include "RHIDefinitions.h"
#include "SceneTypes.h"
#include "SceneInterface.h"
#include "RendererInterface.h"
#include "PrimitiveViewRelevance.h"
#include "Materials/Material.h"
#include "MaterialShared.h"
#include "PrimitiveDrawingUtils.h"
#include "ScenePrivateBase.h"
#include "PostProcess/SceneRenderTargets.h"
#include "SceneCore.h"
#include "SceneOcclusion.h"
#include "LightSceneInfo.h"
#include "SceneRendering.h"
#include "DeferredShadingRenderer.h"
#include "DynamicPrimitiveDrawing.h"
#include "FXSystem.h"
#include "PostProcess/PostProcessing.h"
#include "SceneView.h"
#include "SkyAtmosphereRendering.h"
#include "Engine/LODActor.h"
#include "GPUScene.h"
#include "TranslucentRendering.h"
#include "TranslucentLighting.h"
#include "Async/ParallelFor.h"
#include "HairStrands/HairStrandsRendering.h"
#include "HairStrands/HairStrandsData.h"
#include "RectLightSceneProxy.h"
#include "Math/Halton.h"
#include "ProfilingDebugging/CountersTrace.h"
#include "Algo/Unique.h"
#include "InstanceCulling/InstanceCullingManager.h"
#include "InstanceCulling/InstanceCullingOcclusionQuery.h"
#include "PostProcess/TemporalAA.h"
#include "RayTracing/RayTracingInstanceCulling.h"
#include "RayTracing/RayTracing.h"
#include "HeterogeneousVolumes/HeterogeneousVolumes.h"
#include "RendererModule.h"
#include "SceneViewExtension.h"
#include "RenderCore.h"
#include "UnrealEngine.h"
#include "VT/VirtualTextureSystem.h"
#include "NaniteSceneProxy.h"
#include "ViewDebug.h"
#include "DecalRenderingCommon.h"
#include "CompositionLighting/PostProcessDeferredDecals.h"
#include "DecalRenderingShared.h"

bool GDistanceCullToSphereEdge = true;
static FAutoConsoleVariableRef CVarDistanceCullToSphereEdge(
	TEXT("r.DistanceCullToSphereEdge"),
	GDistanceCullToSphereEdge,
	TEXT("If true frustum cull will check distance to bounding sphere edge rather than origin."),
	ECVF_RenderThreadSafe
);

static float GWireframeCullThreshold = 5.0f;
static FAutoConsoleVariableRef CVarWireframeCullThreshold(
	TEXT("r.WireframeCullThreshold"),
	GWireframeCullThreshold,
	TEXT("Threshold below which objects in ortho wireframe views will be culled."),
	ECVF_RenderThreadSafe
	);

float GMinScreenRadiusForLights = 0.03f;
static FAutoConsoleVariableRef CVarMinScreenRadiusForLights(
	TEXT("r.MinScreenRadiusForLights"),
	GMinScreenRadiusForLights,
	TEXT("Threshold below which lights will be culled."),
	ECVF_RenderThreadSafe
	);

float GMinScreenRadiusForDepthPrepass = 0.03f;
static FAutoConsoleVariableRef CVarMinScreenRadiusForDepthPrepass(
	TEXT("r.MinScreenRadiusForDepthPrepass"),
	GMinScreenRadiusForDepthPrepass,
	TEXT("Threshold below which meshes will be culled from depth only pass."),
	ECVF_RenderThreadSafe
	);

static TAutoConsoleVariable<int32> CVarTemporalAASamples(
	TEXT("r.TemporalAASamples"),
	8,
	TEXT("Number of jittered positions for temporal AA (4, 8=default, 16, 32, 64)."),
	ECVF_RenderThreadSafe);

static TAutoConsoleVariable<int32> CVarTemporalAAScaleSamples(
	TEXT("r.TemporalAAScaleSamples"),
	1,
	TEXT("Whether or not to scale the number of jittered positions for temporal AA when upsampling to maintain a consistent density."),
	ECVF_RenderThreadSafe);

static TAutoConsoleVariable<int32> CVarInvertTemporalJitterX(
	TEXT("r.InvertTemporalJitterX"),
	0,
	TEXT("Whether or not to invert the X value of jittered positions for temporal AA."),
	ECVF_RenderThreadSafe);

static TAutoConsoleVariable<int32> CVarInvertTemporalJitterY(
	TEXT("r.InvertTemporalJitterY"),
	0,
	TEXT("Whether or not to invert the Y value of jittered positions for temporal AA."),
	ECVF_RenderThreadSafe);

static int32 GHZBOcclusion = 0;
static FAutoConsoleVariableRef CVarHZBOcclusion(
	TEXT("r.HZBOcclusion"),
	GHZBOcclusion,
	TEXT("Defines which occlusion system is used.\n")
	TEXT(" 0: Hardware occlusion queries\n")
	TEXT(" 1: Use HZB occlusion system (default, less GPU and CPU cost, more conservative results)")
	TEXT(" 2: Force HZB occlusion system (overrides rendering platform preferences)"),
	ECVF_RenderThreadSafe
	);

int32 GOcclusionFeedback_Enable = 0;
static FAutoConsoleVariableRef CVarOcclusionFeedback_Enable(
	TEXT("r.OcclusionFeedback.Enable"),
	GOcclusionFeedback_Enable,
	TEXT("Whether to enable occlusion system based on a rendering feedback. Currently works only with a mobile rendering\n"),
	ECVF_RenderThreadSafe
);

static int32 GVisualizeOccludedPrimitives = 0;
static FAutoConsoleVariableRef CVarVisualizeOccludedPrimitives(
	TEXT("r.VisualizeOccludedPrimitives"),
	GVisualizeOccludedPrimitives,
	TEXT("Draw boxes for all occluded primitives"),
	ECVF_RenderThreadSafe | ECVF_Cheat
	);

static int32 GAllowSubPrimitiveQueries = 1;
static FAutoConsoleVariableRef CVarAllowSubPrimitiveQueries(
	TEXT("r.AllowSubPrimitiveQueries"),
	GAllowSubPrimitiveQueries,
	TEXT("Enables sub primitive queries, currently only used by hierarchical instanced static meshes. 1: Enable, 0 Disabled. When disabled, one query is used for the entire proxy."),
	ECVF_RenderThreadSafe
	);

RENDERER_API TAutoConsoleVariable<float> CVarStaticMeshLODDistanceScale(
	TEXT("r.StaticMeshLODDistanceScale"),
	1.0f,
	TEXT("Scale factor for the distance used in computing discrete LOD for static meshes. (defaults to 1)\n")
	TEXT("(higher values make LODs transition earlier, e.g., 2 is twice as fast / half the distance)"),
	ECVF_Scalability | ECVF_RenderThreadSafe);

static TAutoConsoleVariable<float> CVarAutomaticViewMipBiasMin(
	TEXT("r.ViewTextureMipBias.Min"),
	-2.0f,
	TEXT("Automatic view mip bias's minimum value (default to -2)."),
	ECVF_RenderThreadSafe);

static TAutoConsoleVariable<float> CVarAutomaticViewMipBiasOffset(
	TEXT("r.ViewTextureMipBias.Offset"),
	-0.3,
	TEXT("Automatic view mip bias's constant offset (default to -0.3)."),
	ECVF_RenderThreadSafe);

static TAutoConsoleVariable<int32> CVarAutomaticViewMipBiasQuantization(
	TEXT("r.ViewTextureMipBias.Quantization"),
	1024,
	TEXT("Quantization step count to use for automatic view mip bias, measured between -4.0f and 4.0f.\n")
	TEXT("Lowering this can significantly reduce unique sampler states when Dynamic Resolution is active."),
	ECVF_RenderThreadSafe);

static int32 GILCUpdatePrimTaskEnabled = 1;

static FAutoConsoleVariableRef CVarILCUpdatePrimitivesTask(
	TEXT("r.Cache.UpdatePrimsTaskEnabled"),
	GILCUpdatePrimTaskEnabled,
	TEXT("Enable threading for ILC primitive update.  Will overlap with the rest the end of InitViews."),
	ECVF_RenderThreadSafe
	);

int32 GEarlyInitDynamicShadows = 1;
static FAutoConsoleVariableRef CVarEarlyInitDynamicShadows(
	TEXT("r.EarlyInitDynamicShadows"),
	GEarlyInitDynamicShadows,
	TEXT("Starts shadow culling tasks earlier in the frame."),
	ECVF_RenderThreadSafe
);

static int32 GFramesNotOcclusionTestedToExpandBBoxes = 5;
static FAutoConsoleVariableRef CVarFramesNotOcclusionTestedToExpandBBoxes(
	TEXT("r.GFramesNotOcclusionTestedToExpandBBoxes"),
	GFramesNotOcclusionTestedToExpandBBoxes,
	TEXT("If we don't occlusion test a primitive for this many frames, then we expand the BBox when we do occlusion test it for a few frames. See also r.ExpandNewlyOcclusionTestedBBoxesAmount, r.FramesToExpandNewlyOcclusionTestedBBoxes"),
	ECVF_RenderThreadSafe
);

static int32 GFramesToExpandNewlyOcclusionTestedBBoxes = 2;
static FAutoConsoleVariableRef CVarFramesToExpandNewlyOcclusionTestedBBoxes(
	TEXT("r.FramesToExpandNewlyOcclusionTestedBBoxes"),
	GFramesToExpandNewlyOcclusionTestedBBoxes,
	TEXT("If we don't occlusion test a primitive for r.GFramesNotOcclusionTestedToExpandBBoxes frames, then we expand the BBox when we do occlusion test it for this number of frames. See also r.GFramesNotOcclusionTestedToExpandBBoxes, r.ExpandNewlyOcclusionTestedBBoxesAmount"),
	ECVF_RenderThreadSafe
);

static float GExpandNewlyOcclusionTestedBBoxesAmount = 0.0f;
static FAutoConsoleVariableRef CVarExpandNewlyOcclusionTestedBBoxesAmount(
	TEXT("r.ExpandNewlyOcclusionTestedBBoxesAmount"),
	GExpandNewlyOcclusionTestedBBoxesAmount,
	TEXT("If we don't occlusion test a primitive for r.GFramesNotOcclusionTestedToExpandBBoxes frames, then we expand the BBox when we do occlusion test it for a few frames by this amount. See also r.FramesToExpandNewlyOcclusionTestedBBoxes, r.GFramesNotOcclusionTestedToExpandBBoxes."),
	ECVF_RenderThreadSafe
);

static float GExpandAllTestedBBoxesAmount = 0.0f;
static FAutoConsoleVariableRef CVarExpandAllTestedBBoxesAmount(
	TEXT("r.ExpandAllOcclusionTestedBBoxesAmount"),
	GExpandAllTestedBBoxesAmount,
	TEXT("Amount to expand all occlusion test bounds by."),
	ECVF_RenderThreadSafe
);

static float GNeverOcclusionTestDistance = 0.0f;
static FAutoConsoleVariableRef CVarNeverOcclusionTestDistance(
	TEXT("r.NeverOcclusionTestDistance"),
	GNeverOcclusionTestDistance,
	TEXT("When the distance between the viewpoint and the bounding sphere center is less than this, never occlusion cull."),
	ECVF_RenderThreadSafe | ECVF_Scalability
);

static int32 GForceSceneHasDecals = 0;
static FAutoConsoleVariableRef CVarForceSceneHasDecals(
	TEXT("r.ForceSceneHasDecals"),
	GForceSceneHasDecals,
	TEXT("Whether to always assume that scene has decals, so we don't switch depth state conditionally. This can significantly reduce total number of PSOs at a minor GPU cost."),
	ECVF_RenderThreadSafe
);

static float GCameraCutTranslationThreshold = 10000.0f;
static FAutoConsoleVariableRef CVarCameraCutTranslationThreshold(
	TEXT("r.CameraCutTranslationThreshold"),
	GCameraCutTranslationThreshold,
	TEXT("The maximum camera translation disatance in centimeters allowed between two frames before a camera cut is automatically inserted."),
	ECVF_RenderThreadSafe
);

/** Distance fade cvars */
static int32 GDisableLODFade = false;
static FAutoConsoleVariableRef CVarDisableLODFade( TEXT("r.DisableLODFade"), GDisableLODFade, TEXT("Disable fading for distance culling"), ECVF_RenderThreadSafe );

static float GFadeTime = 0.25f;
static FAutoConsoleVariableRef CVarLODFadeTime( TEXT("r.LODFadeTime"), GFadeTime, TEXT("How long LOD takes to fade (in seconds)."), ECVF_RenderThreadSafe );

static float GDistanceFadeMaxTravel = 1000.0f;
static FAutoConsoleVariableRef CVarDistanceFadeMaxTravel( TEXT("r.DistanceFadeMaxTravel"), GDistanceFadeMaxTravel, TEXT("Max distance that the player can travel during the fade time."), ECVF_RenderThreadSafe );

extern int32 GVisibilitySkipAlwaysVisible;

static int32 GVisibilityTaskSchedule = 1;
static FAutoConsoleVariableRef CVarVisibilityTaskSchedule(
	TEXT("r.Visibility.TaskSchedule"),
	GVisibilityTaskSchedule,
	TEXT("Controls how the visibility task graph is scheduled.")
	TEXT("0: Work is primarily done on the render thread with the potential for parallel help;")
	TEXT("1: Work is done on an async task graph (if supported by platform);"),
	ECVF_RenderThreadSafe
);

static int32 GFrustumCullNumPrimitivesPerTask = 0;
static FAutoConsoleVariableRef CVarFrustumCullNumPrimitivesPerTask(
	TEXT("r.Visibility.FrustumCull.NumPrimitivesPerTask"),
	GFrustumCullNumPrimitivesPerTask,
	TEXT("Assigns a fixed number of primitives for each frustum cull task.")
	TEXT(" 0: Automatic;")
	TEXT(">0: Fixed number of primitives per task (clamped to fixed limits);"),
	ECVF_RenderThreadSafe
);

static bool GFrustumCullEnabled = true;
static FAutoConsoleVariableRef CVarFrustumCullEnable(
	TEXT("r.Visibility.FrustumCull.Enabled"),
	GFrustumCullEnabled,
	TEXT("Enables frustum culling."),
	ECVF_RenderThreadSafe
);

static bool GFrustumCullUseOctree = false;
static FAutoConsoleVariableRef CVarFrustumCullUseOctree(
	TEXT("r.Visibility.FrustumCull.UseOctree"),
	GFrustumCullUseOctree,
	TEXT("Use the octree for visibility calculations."),
	ECVF_RenderThreadSafe
);

static bool GFrustumCullUseSphereTestFirst = false;
static FAutoConsoleVariableRef CVarFrustumCullUseSphereTestFirst(
	TEXT("r.Visibility.FrustumCull.UseSphereTestFirst"),
	GFrustumCullUseSphereTestFirst,
	TEXT("Performance tweak. Uses a sphere cull before and in addition to a box for frustum culling."),
	ECVF_RenderThreadSafe
);

static bool GFrustumCullUseFastIntersect = true;
static FAutoConsoleVariableRef CVarFrustumCullUseFastIntersect(
	TEXT("r.Visibility.FrustumCull.UseFastIntersect"),
	GFrustumCullUseFastIntersect,
	TEXT("Use optimized 8 plane fast intersection code if we have 8 permuted planes."),
	ECVF_RenderThreadSafe
);

static int32 GOcclusionCullMaxQueriesPerTask = 0;
static FAutoConsoleVariableRef CVarOcclusionCullMaxQueriesPerTask(
	TEXT("r.Visibility.OcclusionCull.MaxQueriesPerTask"),
	GOcclusionCullMaxQueriesPerTask,
	TEXT("Assigns a fixed number of occlusion queries for each occlusion cull task.")
	TEXT(" 0: Automatic;")
	TEXT(">0: Fixed number of occlusion queries per task;"),
	ECVF_RenderThreadSafe
);

static int32 GNumDynamicMeshElementTasks = 4;
static FAutoConsoleVariableRef CVarNumDynamicMeshElementTasks(
	TEXT("r.Visibility.DynamicMeshElements.NumMainViewTasks"),
	GNumDynamicMeshElementTasks,
	TEXT("Controls the number of gather dynamic mesh elements tasks to run asynchronously during view visibility."),
	ECVF_RenderThreadSafe
);

inline uint32 GetNumDynamicMeshElementTasks()
{
	if (!IsParallelGatherDynamicMeshElementsEnabled())
	{
		return 0;
	}

	return FMath::Clamp<int32>(GNumDynamicMeshElementTasks, 0, LowLevelTasks::FScheduler::Get().GetNumWorkers());
}

static bool GOcclusionCullEnabled = true;
static FAutoConsoleVariableRef CVarOcclusionCullEnable(
	// TODO: Move to r.Visibility.OcclusionCull.Enable. Still several explicit references.
	TEXT("r.AllowOcclusionQueries"),
	GOcclusionCullEnabled,
	TEXT("Enables hardware occlusion culling."),
	ECVF_RenderThreadSafe
);

bool FSceneRenderer::DoOcclusionQueries() const
{
	return GOcclusionCullEnabled && !ViewFamily.EngineShowFlags.DisableOcclusionQueries;
}

static int32 GRelevanceNumPrimitivesPerPacket = 0;
static FAutoConsoleVariableRef CVarRelevanceNumPrimitivesPerPacket(
	TEXT("r.Visibility.Relevance.NumPrimitivesPerPacket"),
	GRelevanceNumPrimitivesPerPacket,
	TEXT("Assigns a fixed number of primitives for each relevance packet.")
	TEXT(" 0: Automatic;")
	TEXT(">0: Fixed number of primitives per packet (clamped to fixed limits);"),
	ECVF_RenderThreadSafe
);

float GLightMaxDrawDistanceScale = 1.0f;
static FAutoConsoleVariableRef CVarLightMaxDrawDistanceScale(
	TEXT("r.LightMaxDrawDistanceScale"),
	GLightMaxDrawDistanceScale,
	TEXT("Scale applied to the MaxDrawDistance of lights.  Useful for fading out local lights more aggressively on some platforms."),
	ECVF_Scalability | ECVF_RenderThreadSafe
);

#if !UE_BUILD_SHIPPING

static TAutoConsoleVariable<int32> CVarTAADebugOverrideTemporalIndex(
	TEXT("r.TemporalAA.Debug.OverrideTemporalIndex"), -1,
	TEXT("Override the temporal index for debugging purposes."),
	ECVF_RenderThreadSafe);

static TAutoConsoleVariable<float> CVarFreezeTemporalSequences(
	TEXT("r.Test.FreezeTemporalSequences"), 0,
	TEXT("Freezes all temporal sequences."),
	ECVF_RenderThreadSafe);

static TAutoConsoleVariable<float> CVarFreezeTemporalHistories(
	TEXT("r.Test.FreezeTemporalHistories"), 0,
	TEXT("Freezes all temporal histories as well as the temporal sequence."),
	ECVF_RenderThreadSafe);

static TAutoConsoleVariable<float> CVarFreezeTemporalHistoriesProgress(
	TEXT("r.Test.FreezeTemporalHistories.Progress"), 0,
	TEXT("Progress the temporal histories by one frame when modified."),
	ECVF_RenderThreadSafe);

#endif

TRACE_DECLARE_INT_COUNTER(Scene_Visibility_NumProcessedPrimitives, TEXT("Scene/Visibility/NumProcessedPrimitives"));
TRACE_DECLARE_INT_COUNTER(Scene_Visibility_FrustumCull_NumCulledPrimitives, TEXT("Scene/Visibility/FrustumCull/NumCulledPrimitives"));
TRACE_DECLARE_INT_COUNTER(Scene_Visibility_FrustumCull_NumPrimitivesPerTask, TEXT("Scene/Visibility/FrustumCull/NumPrimitivesPerTask"));
TRACE_DECLARE_INT_COUNTER(Scene_Visibility_OcclusionCull_NumTestedQueries, TEXT("Scene/Visibility/OcclusionCull/NumTestedQueries"));
TRACE_DECLARE_INT_COUNTER(Scene_Visibility_OcclusionCull_NumCulledPrimitives, TEXT("Scene/Visibility/OcclusionCull/NumCulledPrimitives"));
TRACE_DECLARE_INT_COUNTER(Scene_Visibility_Relevance_NumPrimitivesPerPacket, TEXT("Scene/Visibility/Relevance/NumPrimitivesPerPacket"));
TRACE_DECLARE_INT_COUNTER(Scene_Visibility_Relevance_NumPrimitivesProcessed, TEXT("Scene/Visibility/Relevance/NumPrimitivesProcessed"));

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

IVisibilityTaskData* LaunchVisibilityTasks(FRHICommandListImmediate& RHICmdList, FSceneRenderer& SceneRenderer, const UE::Tasks::FTask& BeginInitVisibilityPrerequisites)
{
	FVisibilityTaskData* TaskData = SceneRenderer.Allocator.Create<FVisibilityTaskData>(RHICmdList, SceneRenderer);
	TaskData->LaunchVisibilityTasks(BeginInitVisibilityPrerequisites);
	return TaskData;
}

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

bool FViewInfo::IsDistanceCulled( float DistanceSquared, float MinDrawDistance, float InMaxDrawDistance, const FPrimitiveSceneInfo* PrimitiveSceneInfo)
{
	bool bMayBeFading;
	bool bFadingIn;
	bool bDistanceCulled = IsDistanceCulled_AnyThread(DistanceSquared, MinDrawDistance, InMaxDrawDistance, PrimitiveSceneInfo, bMayBeFading, bFadingIn);

	if (bMayBeFading)
	{
		bDistanceCulled = UpdatePrimitiveFadingState(PrimitiveSceneInfo, bFadingIn);
	}

	return bDistanceCulled;
}

bool FViewInfo::IsDistanceCulled_AnyThread(float DistanceSquared, float InMinDrawDistance, float InMaxDrawDistance, const FPrimitiveSceneInfo* PrimitiveSceneInfo, bool& bOutMayBeFading, bool& bOutFadingIn) const
{
	const float MaxDrawDistanceScale = GetCachedScalabilityCVars().ViewDistanceScale;
	const float FadeRadius = GDisableLODFade ? 0.0f : GDistanceFadeMaxTravel;
	const float MaxDrawDistance = InMaxDrawDistance * MaxDrawDistanceScale;
	const float MinDrawDistance = InMinDrawDistance * MaxDrawDistanceScale;

	bool bHasMaxDrawDistance = InMaxDrawDistance != FLT_MAX;
	bool bHasMinDrawDistance = InMinDrawDistance > 0;
	bOutMayBeFading = false;


	if (!bHasMaxDrawDistance && !bHasMinDrawDistance)
	{
		return false;
	}

	// If cull distance is disabled, always show (except foliage)
	if (Family->EngineShowFlags.DistanceCulledPrimitives && !PrimitiveSceneInfo->Proxy->IsDetailMesh())
	{
		return false;
	}

	// The primitive is always culled if it exceeds the max fade distance.
	if ((bHasMaxDrawDistance && DistanceSquared > FMath::Square(MaxDrawDistance + FadeRadius)) || (bHasMinDrawDistance && DistanceSquared < FMath::Square(MinDrawDistance)))
	{
		return true;
	}

	const bool bDistanceCulled = bHasMaxDrawDistance && (DistanceSquared > FMath::Square(MaxDrawDistance));
	const bool bMayBeFading = bHasMaxDrawDistance && (DistanceSquared > FMath::Square(MaxDrawDistance - FadeRadius));

	if (!GDisableLODFade && bMayBeFading && State != NULL && !bDisableDistanceBasedFadeTransitions && PrimitiveSceneInfo->Proxy->IsUsingDistanceCullFade())
	{
		// Don't update primitive fading state yet because current thread may be not render thread
		bOutMayBeFading = true;
		bOutFadingIn = !bDistanceCulled;
	}

	return bDistanceCulled && !bOutMayBeFading;
}

inline bool IntersectBox8Plane(const FVector& InOrigin, const FVector& InExtent, const FPlane*PermutedPlanePtr)
{
	// this removes a lot of the branches as we know there's 8 planes
	// copied directly out of ConvexVolume.cpp
	const VectorRegister Origin = VectorLoadFloat3(&InOrigin);
	const VectorRegister Extent = VectorLoadFloat3(&InExtent);

	const VectorRegister PlanesX_0 = VectorLoadAligned(&PermutedPlanePtr[0]);
	const VectorRegister PlanesY_0 = VectorLoadAligned(&PermutedPlanePtr[1]);
	const VectorRegister PlanesZ_0 = VectorLoadAligned(&PermutedPlanePtr[2]);
	const VectorRegister PlanesW_0 = VectorLoadAligned(&PermutedPlanePtr[3]);

	const VectorRegister PlanesX_1 = VectorLoadAligned(&PermutedPlanePtr[4]);
	const VectorRegister PlanesY_1 = VectorLoadAligned(&PermutedPlanePtr[5]);
	const VectorRegister PlanesZ_1 = VectorLoadAligned(&PermutedPlanePtr[6]);
	const VectorRegister PlanesW_1 = VectorLoadAligned(&PermutedPlanePtr[7]);

	// Splat origin into 3 vectors
	VectorRegister OrigX = VectorReplicate(Origin, 0);
	VectorRegister OrigY = VectorReplicate(Origin, 1);
	VectorRegister OrigZ = VectorReplicate(Origin, 2);
	// Splat the already abs Extent for the push out calculation
	VectorRegister AbsExtentX = VectorReplicate(Extent, 0);
	VectorRegister AbsExtentY = VectorReplicate(Extent, 1);
	VectorRegister AbsExtentZ = VectorReplicate(Extent, 2);

	// Calculate the distance (x * x) + (y * y) + (z * z) - w
	VectorRegister DistX_0 = VectorMultiply(OrigX, PlanesX_0);
	VectorRegister DistY_0 = VectorMultiplyAdd(OrigY, PlanesY_0, DistX_0);
	VectorRegister DistZ_0 = VectorMultiplyAdd(OrigZ, PlanesZ_0, DistY_0);
	VectorRegister Distance_0 = VectorSubtract(DistZ_0, PlanesW_0);
	// Now do the push out FMath::Abs(x * x) + FMath::Abs(y * y) + FMath::Abs(z * z)
	VectorRegister PushX_0 = VectorMultiply(AbsExtentX, VectorAbs(PlanesX_0));
	VectorRegister PushY_0 = VectorMultiplyAdd(AbsExtentY, VectorAbs(PlanesY_0), PushX_0);
	VectorRegister PushOut_0 = VectorMultiplyAdd(AbsExtentZ, VectorAbs(PlanesZ_0), PushY_0);

	// Check for completely outside
	if (VectorAnyGreaterThan(Distance_0, PushOut_0))
	{
		return false;
	}

	// Calculate the distance (x * x) + (y * y) + (z * z) - w
	VectorRegister DistX_1 = VectorMultiply(OrigX, PlanesX_1);
	VectorRegister DistY_1 = VectorMultiplyAdd(OrigY, PlanesY_1, DistX_1);
	VectorRegister DistZ_1 = VectorMultiplyAdd(OrigZ, PlanesZ_1, DistY_1);
	VectorRegister Distance_1 = VectorSubtract(DistZ_1, PlanesW_1);
	// Now do the push out FMath::Abs(x * x) + FMath::Abs(y * y) + FMath::Abs(z * z)
	VectorRegister PushX_1 = VectorMultiply(AbsExtentX, VectorAbs(PlanesX_1));
	VectorRegister PushY_1 = VectorMultiplyAdd(AbsExtentY, VectorAbs(PlanesY_1), PushX_1);
	VectorRegister PushOut_1 = VectorMultiplyAdd(AbsExtentZ, VectorAbs(PlanesZ_1), PushY_1);

	// Check for completely outside
	if (VectorAnyGreaterThan(Distance_1, PushOut_1))
	{
		return false;
	}
	return true;
}

struct FFrustumCullingFlags
{
	bool bShouldVisibilityCull;
	bool bUseCustomCulling;
	bool bUseSphereTestFirst;
	bool bUseFastIntersect;
	bool bUseVisibilityOctree;
	bool bHasHiddenPrimitives;
	bool bHasShowOnlyPrimitives;
};

// Returns true if the frustum and bounds intersect
inline bool IsPrimitiveVisible(FViewInfo& View, const FPlane* PermutedPlanePtr, const FConvexVolume& ViewCullingFrustum, const FPrimitiveBounds& Bounds, int32 VisibilityId, FFrustumCullingFlags Flags)
{
	// The custom culling and sphere culling are additional tests, meaning that if they pass, the
	// remaining culling tests will still be performed.  If any of the tests fail, then the primitive
	// is culled, and the remaining tests do not need be performed

	if (Flags.bUseCustomCulling && !View.CustomVisibilityQuery->IsVisible(VisibilityId, FBoxSphereBounds(Bounds.BoxSphereBounds.Origin, Bounds.BoxSphereBounds.BoxExtent, Bounds.BoxSphereBounds.SphereRadius)))
	{
		return false;
	}

	if (Flags.bUseSphereTestFirst && !ViewCullingFrustum.IntersectSphere(Bounds.BoxSphereBounds.Origin, Bounds.BoxSphereBounds.SphereRadius))
	{
		return false;
	}

	if (Flags.bUseFastIntersect)
	{
		return IntersectBox8Plane(Bounds.BoxSphereBounds.Origin, Bounds.BoxSphereBounds.BoxExtent, PermutedPlanePtr);
	}
	else
	{
		return ViewCullingFrustum.IntersectBox(Bounds.BoxSphereBounds.Origin, Bounds.BoxSphereBounds.BoxExtent);
	}
}

inline bool IsPrimitiveHidden(const FScene& Scene, FViewInfo& View, int32 PrimitiveIndex, FFrustumCullingFlags Flags)
{
	// If any primitives are explicitly hidden, remove them now.
	if (Flags.bHasHiddenPrimitives && View.HiddenPrimitives.Contains(Scene.PrimitiveComponentIds[PrimitiveIndex]))
	{
		return true;
	}

	// If the view has any show only primitives, hide everything else
	if (Flags.bHasShowOnlyPrimitives && !View.ShowOnlyPrimitives->Contains(Scene.PrimitiveComponentIds[PrimitiveIndex]))
	{
		return true;
	}

	return false;
}

#if RHI_RAYTRACING

inline bool ShouldCullForRayTracing(const FScene& Scene, FViewInfo& View, int32 PrimitiveIndex)
{
	const FRayTracingCullingParameters& RayTracingCullingParameters = View.RayTracingCullingParameters;

	if (RayTracing::CullPrimitiveByFlags(RayTracingCullingParameters, &Scene, PrimitiveIndex))
	{
		return true;
	}

	const bool bIsFarFieldPrimitive = EnumHasAnyFlags(Scene.PrimitiveRayTracingFlags[PrimitiveIndex], ERayTracingPrimitiveFlags::FarField);
	const Experimental::FHashElementId GroupId = Scene.PrimitiveRayTracingGroupIds[PrimitiveIndex];

	if (RayTracingCullingParameters.bCullUsingGroupIds && GroupId.IsValid())
	{
		const FBoxSphereBounds& GroupBounds = Scene.PrimitiveRayTracingGroups.GetByElementId(GroupId).Value.Bounds;
		const float GroupMinDrawDistance = Scene.PrimitiveRayTracingGroups.GetByElementId(GroupId).Value.MinDrawDistance;
		return RayTracing::ShouldCullBounds(RayTracingCullingParameters, GroupBounds, GroupMinDrawDistance, bIsFarFieldPrimitive);
	}
	else
	{
		const FPrimitiveBounds& RESTRICT Bounds = Scene.PrimitiveBounds[PrimitiveIndex];
		return RayTracing::ShouldCullBounds(RayTracingCullingParameters, Bounds.BoxSphereBounds, Bounds.MinDrawDistance, bIsFarFieldPrimitive);
	}
};
#endif //RHI_RAYTRACING

inline void ComputeDistances(const FPrimitiveBounds& Bounds, const FVector& ViewOriginForDistanceCulling, float& OutClosestDistSq, float& OutFurthestDistSq)
{
	float Dist = (Bounds.BoxSphereBounds.Origin - ViewOriginForDistanceCulling).Length();
	float ClosestDist = Dist - Bounds.BoxSphereBounds.SphereRadius;
	float FurthestDist = Dist + Bounds.BoxSphereBounds.SphereRadius;

	OutClosestDistSq = Dist >= Bounds.BoxSphereBounds.SphereRadius ? FMath::Square(ClosestDist) : 0;
	OutFurthestDistSq = FMath::Square(FurthestDist);
}

static void CullOctree(const FScene& Scene, FViewInfo& View, const FFrustumCullingFlags& Flags, FSceneBitArray& OutVisibleNodes, const FConvexVolume& ViewCullingFrustum)
{
	TRACE_CPUPROFILER_EVENT_SCOPE(SceneVisibility_CullOctree);

	// Two bits per octree node, 1st bit is Inside Frustum, 2nd bit is Outside Frustum
	OutVisibleNodes.Init(false, Scene.PrimitiveOctree.GetNumNodes() * 2);

	Scene.PrimitiveOctree.FindNodesWithPredicate(
		[&View, &OutVisibleNodes, &Flags, &ViewCullingFrustum](FScenePrimitiveOctree::FNodeIndex ParentNodeIndex, FScenePrimitiveOctree::FNodeIndex NodeIndex, const FBoxCenterAndExtent& NodeBounds)
		{
			// If the parent node is completely contained there is no need to test containment
			if (ParentNodeIndex != INDEX_NONE && !OutVisibleNodes[(ParentNodeIndex * 2) + 1])
			{
				OutVisibleNodes[NodeIndex * 2] = true;
				OutVisibleNodes[NodeIndex * 2 + 1] = false;
				return true;
			}

			const FPlane* PermutedPlanePtr = ViewCullingFrustum.PermutedPlanes.GetData();
			bool bIntersects = false;

			if (Flags.bUseFastIntersect)
			{
				bIntersects = IntersectBox8Plane(NodeBounds.Center, NodeBounds.Extent, PermutedPlanePtr);
			}
			else
			{
				bIntersects = ViewCullingFrustum.IntersectBox(NodeBounds.Center, NodeBounds.Extent);
			}

			if (bIntersects)
			{
				OutVisibleNodes[NodeIndex * 2] = true;
				OutVisibleNodes[NodeIndex * 2 + 1] = ViewCullingFrustum.GetBoxIntersectionOutcode(NodeBounds.Center, NodeBounds.Extent).GetOutside();
			}

			return bIntersects;
		},
		[](FScenePrimitiveOctree::FNodeIndex /*ParentNodeIndex*/, FScenePrimitiveOctree::FNodeIndex /*NodeIndex*/, const FBoxCenterAndExtent& /*NodeBounds*/)
		{

		});
}

static void UpdateAlwaysVisible(const FScene& Scene, FViewInfo& View, FFrustumCullingFlags Flags, const FVisibilityTaskConfig& TaskConfig, int32 TaskIndex, float CurrentWorldTime)
{
	QUICK_SCOPE_CYCLE_COUNTER(STAT_AlwaysVisible_Loop);

	check(Scene.PrimitivesAlwaysVisibleOffset != ~0u);
	const int32 BitArrayNumInner = TaskConfig.NumVisiblePrimitives;
	const int32 StartWord = int32(Scene.PrimitivesAlwaysVisibleOffset) / NumBitsPerDWORD;
	const int32 TaskWordOffset = TaskIndex * TaskConfig.AlwaysVisible.NumWordsPerTask;

	uint32* RESTRICT VisWords = View.PrimitiveVisibilityMap.GetData();
#if RHI_RAYTRACING
	uint32* RESTRICT  RTWords = View.PrimitiveRayTracingVisibilityMap.GetData();

	const bool bRayTracingEnabled = IsRayTracingEnabled(View.GetShaderPlatform()) && View.IsRayTracingAllowedForView();
#endif

	for (int32 WordIndex = TaskWordOffset; WordIndex < TaskWordOffset + int32(TaskConfig.AlwaysVisible.NumWordsPerTask) && WordIndex * NumBitsPerDWORD < BitArrayNumInner; ++WordIndex)
	{
		uint32 Mask = 0x1;

		uint32 VisBits = 0;
	#if RHI_RAYTRACING
		uint32 RayTracingBits = 0;
	#endif

		for (int32 BitSubIndex = 0; BitSubIndex < NumBitsPerDWORD && WordIndex * NumBitsPerDWORD + BitSubIndex < BitArrayNumInner; ++BitSubIndex, Mask <<= 1)
		{
			const int32 Index = (StartWord + WordIndex) * NumBitsPerDWORD + BitSubIndex;
			VisBits |= Mask;

		#if RHI_RAYTRACING
			if (bRayTracingEnabled && !IsPrimitiveHidden(Scene, View, Index, Flags) && !ShouldCullForRayTracing(Scene, View, Index))
			{
				RayTracingBits |= Mask;
			}
		#endif
		}

		VisWords[StartWord + WordIndex] = VisBits;

	#if RHI_RAYTRACING
		if (RayTracingBits)
		{
			RTWords[StartWord + WordIndex] = RayTracingBits;
		}
	#endif
	}
}

static int32 FrustumCull(const FScene& Scene, FViewInfo& View, FFrustumCullingFlags Flags, float MaxDrawDistanceScale, const FHLODVisibilityState* const HLODState, const FSceneBitArray* VisibleNodes, const FVisibilityTaskConfig& TaskConfig, int32 TaskIndex)
{
	QUICK_SCOPE_CYCLE_COUNTER(STAT_FrustumCull_Loop);

	bool bDisableLODFade = GDisableLODFade || View.bDisableDistanceBasedFadeTransitions;
	const FPlane* PermutedPlanePtr = View.GetCullingFrustum().PermutedPlanes.GetData();
	const FConvexVolume& ViewCullingFrustum = View.GetCullingFrustum();
	FVector ViewOriginForDistanceCulling = View.CullingOrigin;
	float FadeRadius = bDisableLODFade ? 0.0f : GDistanceFadeMaxTravel;
	uint8 CustomVisibilityFlags = EOcclusionFlags::CanBeOccluded | EOcclusionFlags::HasPrecomputedVisibility;

	int32 BitArrayNumInner = TaskConfig.NumTestedPrimitives;

	uint32 NumPrimitivesCulledForTask = 0;

	// Primitives may be explicitly removed from stereo views when using mono
	const int32 TaskWordOffset = TaskIndex * TaskConfig.FrustumCull.NumWordsPerTask;

	uint32* RESTRICT VisWords = View.PrimitiveVisibilityMap.GetData();
	uint32* RESTRICT FadeWords = View.PotentiallyFadingPrimitiveMap.GetData();
#if RHI_RAYTRACING
	uint32* RESTRICT  RTWords = View.PrimitiveRayTracingVisibilityMap.GetData();

	const bool bRayTracingEnabled = IsRayTracingEnabled(View.GetShaderPlatform()) && View.IsRayTracingAllowedForView();
#endif

	for (int32 WordIndex = TaskWordOffset; WordIndex < TaskWordOffset + int32(TaskConfig.FrustumCull.NumWordsPerTask) && WordIndex * NumBitsPerDWORD < BitArrayNumInner; WordIndex++)
	{
		uint32 Mask = 0x1; 
		uint32 VisBits = 0;
		uint32 FadingBits = 0;
	#if RHI_RAYTRACING
		uint32 RayTracingBits = 0;
	#endif

		// If visibility culling is disabled, make sure to use the existing visibility state
		if (!Flags.bShouldVisibilityCull)
		{
			VisBits = VisWords[WordIndex];
		}

		for (int32 BitSubIndex = 0; BitSubIndex < NumBitsPerDWORD && WordIndex * NumBitsPerDWORD + BitSubIndex < BitArrayNumInner; BitSubIndex++, Mask <<= 1)
		{
			int32 Index = WordIndex * NumBitsPerDWORD + BitSubIndex;
			bool bPrimitiveIsHidden = IsPrimitiveHidden(Scene, View, Index, Flags);
			bool bIsVisible = Flags.bShouldVisibilityCull ? true : (VisBits & Mask) == Mask;

			bIsVisible = bIsVisible && !bPrimitiveIsHidden;

		#if RHI_RAYTRACING
			bool bIsVisibleInRayTracing = true;

			if (bPrimitiveIsHidden || !bRayTracingEnabled || ShouldCullForRayTracing(Scene, View, Index))
			{
				bIsVisibleInRayTracing = false;
			}
		#endif

			const FPrimitiveBounds& RESTRICT Bounds = Scene.PrimitiveBounds[Index];

			// Zero sized bounds indicates that we are not visible.
			bIsVisible &= Bounds.BoxSphereBounds.SphereRadius > 0;

			if (Flags.bShouldVisibilityCull && bIsVisible)
			{
				bool bShouldDistanceCull = true;
				bool bPartiallyOutside = true;
				bool bShouldFrustumCull = true;

				// Fading HLODs and their children must be visible, objects hidden by HLODs can be culled
				if (HLODState)
				{
					if (HLODState->IsNodeForcedVisible(Index))
					{
						bShouldDistanceCull = false;
					}
					else if (HLODState->IsNodeForcedHidden(Index))
					{
						bIsVisible = false;
					}
				}

				// Frustum first
				bShouldFrustumCull = bShouldFrustumCull && bIsVisible;
				if (bShouldFrustumCull)
				{
					if (Flags.bUseVisibilityOctree)
					{
						// If the parent octree node was completely contained by the frustum, there is no need do an additional frustum test on the primitive bounds
						// If the parent octree node is partially in the frustum, perform an additional test on the primitive bounds
						uint32 OctreeNodeIndex = Scene.PrimitiveOctreeIndex[Index];

						bIsVisible = (*VisibleNodes)[OctreeNodeIndex * 2];
						bPartiallyOutside = (*VisibleNodes)[OctreeNodeIndex * 2 + 1];
					}

					if (bIsVisible)
					{
						int32 VisibilityId = INDEX_NONE;

						if (Flags.bUseCustomCulling &&
							((Scene.PrimitiveOcclusionFlags[Index] & CustomVisibilityFlags) == CustomVisibilityFlags))
						{
							VisibilityId = Scene.PrimitiveSceneProxies[Index]->GetVisibilityId();
						}

						bIsVisible = !bPartiallyOutside || IsPrimitiveVisible(View, PermutedPlanePtr, ViewCullingFrustum, Bounds, VisibilityId, Flags);
					}
				}

				// Distance cull if frustum cull passed
				bShouldDistanceCull = bShouldDistanceCull && bIsVisible;
				if (bShouldDistanceCull)
				{
					// If cull distance is disabled, always show the primitive (except foliage)
					if (View.Family->EngineShowFlags.DistanceCulledPrimitives
						&& !Scene.PrimitiveSceneProxies[Index]->IsDetailMesh()) // Proxy call is intentionally behind the DistancedCulledPrimitives check to prevent an expensive memory read
					{
						bShouldDistanceCull = false;
					}
				}

				if (bShouldDistanceCull)
				{
					// Preserve infinite draw distance
					bool bHasMaxDrawDistance = Bounds.MaxCullDistance < FLT_MAX;
					bool bHasMinDrawDistance = Bounds.MinDrawDistance > 0;

					if (bHasMaxDrawDistance || bHasMinDrawDistance)
					{
						float MaxDrawDistance = Bounds.MaxCullDistance * MaxDrawDistanceScale;
						float MinDrawDistanceSq = FMath::Square(Bounds.MinDrawDistance * MaxDrawDistanceScale);
						float ClosestDistSquared, FurthestDistSquared;

						if (GDistanceCullToSphereEdge)
						{
							ComputeDistances(Bounds, ViewOriginForDistanceCulling, ClosestDistSquared, FurthestDistSquared);
						}
						else
						{
							ClosestDistSquared = FurthestDistSquared = FVector::DistSquared(Bounds.BoxSphereBounds.Origin, ViewOriginForDistanceCulling);
						}

						// Always test the fade in distance.  If a primitive was set to always draw, it may need to be faded in.
						if (bHasMaxDrawDistance)
						{
							float MaxFadeDistanceSquared = FMath::Square(MaxDrawDistance + FadeRadius);
							float MinFadeDistanceSquared = FMath::Square(MaxDrawDistance - FadeRadius);
							if ((ClosestDistSquared < MaxFadeDistanceSquared && ClosestDistSquared > MinFadeDistanceSquared)
								&& Scene.PrimitiveSceneProxies[Index]->IsUsingDistanceCullFade())  // Proxy call is intentionally behind the fade check to prevent an expensive memory read
							{
								FadingBits |= Mask;
							}
						}

						// Check for distance culling first
						const bool bFarDistanceCulled = bHasMaxDrawDistance && (ClosestDistSquared > FMath::Square(MaxDrawDistance));
						const bool bNearDistanceCulled = bHasMinDrawDistance && (FurthestDistSquared < MinDrawDistanceSq);

						bool bIsDistanceCulled = bNearDistanceCulled || bFarDistanceCulled;

						if (bIsDistanceCulled)
						{
							bIsVisible = false;
						}

					#if RHI_RAYTRACING
						if (bFarDistanceCulled)
						{
							bIsVisibleInRayTracing = false;
						}
					#endif
					}
				}
			}

			if (bIsVisible)
			{
				// The primitive is visible!
				VisBits |= Mask;
			}
			else
			{
				++NumPrimitivesCulledForTask;
			}

		#if RHI_RAYTRACING
			if (bIsVisibleInRayTracing)
			{
				RayTracingBits |= Mask;
			}
		#endif
		}

		if (Flags.bShouldVisibilityCull && FadingBits)
		{
			FadeWords[WordIndex] = FadingBits;
		}

		if (Flags.bShouldVisibilityCull && VisBits)
		{
			VisWords[WordIndex] = VisBits;
		}

	#if RHI_RAYTRACING
		if (RayTracingBits)
		{
			RTWords[WordIndex] = RayTracingBits;
		}
	#endif
	}

	return NumPrimitivesCulledForTask;
}

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

static void ClearStalePrimitiveFadingStates(FViewInfo& View, FSceneViewState* ViewState)
{
	if (!ViewState)
	{
		return;
	}

	const uint32 PrevFrameNumber = ViewState->PrevFrameNumber;
	const float CurrentRealTime = View.Family->Time.GetRealTimeSeconds();

	// First clear any stale fading states.
	for (FPrimitiveFadingStateMap::TIterator It(ViewState->PrimitiveFadingStates); It; ++It)
	{
		FPrimitiveFadingState& FadingState = It.Value();
		if (FadingState.FrameNumber != PrevFrameNumber ||
			(IsValidRef(FadingState.UniformBuffer) && CurrentRealTime >= FadingState.EndTime))
		{
			It.RemoveCurrent();
		}
	}
}

static void UpdatePrimitiveFadingStateHelper(FPrimitiveFadingState& FadingState, const FViewInfo& View, bool bVisible)
{
	if (FadingState.bValid)
	{
		if (FadingState.bIsVisible != bVisible)
		{
			float CurrentRealTime = View.Family->Time.GetRealTimeSeconds();

			// Need to kick off a fade, so make sure that we have fading state for that
			if (!IsValidRef(FadingState.UniformBuffer))
			{
				// Primitive is not currently fading.  Start a new fade!
				FadingState.EndTime = CurrentRealTime + GFadeTime;

				if (bVisible)
				{
					// Fading in
					// (Time - StartTime) / FadeTime
					FadingState.FadeTimeScaleBias.X = 1.0f / GFadeTime;
					FadingState.FadeTimeScaleBias.Y = -CurrentRealTime / GFadeTime;
				}
				else
				{
					// Fading out
					// 1 - (Time - StartTime) / FadeTime
					FadingState.FadeTimeScaleBias.X = -1.0f / GFadeTime;
					FadingState.FadeTimeScaleBias.Y = 1.0f + CurrentRealTime / GFadeTime;
				}

				FDistanceCullFadeUniformShaderParameters Uniforms;
				Uniforms.FadeTimeScaleBias = FVector2f(FadingState.FadeTimeScaleBias);	// LWC_TODO: Precision loss
				FadingState.UniformBuffer = FDistanceCullFadeUniformBufferRef::CreateUniformBufferImmediate(Uniforms, UniformBuffer_MultiFrame);
			}
			else
			{
				// Reverse fading direction but maintain current opacity
				// Solve for d: a*x+b = -a*x+d
				FadingState.FadeTimeScaleBias.Y = 2.0f * CurrentRealTime * FadingState.FadeTimeScaleBias.X + FadingState.FadeTimeScaleBias.Y;
				FadingState.FadeTimeScaleBias.X = -FadingState.FadeTimeScaleBias.X;

				if (bVisible)
				{
					// Fading in
					// Solve for x: a*x+b = 1
					FadingState.EndTime = (1.0f - FadingState.FadeTimeScaleBias.Y) / FadingState.FadeTimeScaleBias.X;
				}
				else
				{
					// Fading out
					// Solve for x: a*x+b = 0
					FadingState.EndTime = -FadingState.FadeTimeScaleBias.Y / FadingState.FadeTimeScaleBias.X;
				}

				FDistanceCullFadeUniformShaderParameters Uniforms;
				Uniforms.FadeTimeScaleBias = FVector2f(FadingState.FadeTimeScaleBias);	// LWC_TODO: Precision loss
				FadingState.UniformBuffer = FDistanceCullFadeUniformBufferRef::CreateUniformBufferImmediate(Uniforms, UniformBuffer_MultiFrame);
			}
		}
	}

	FadingState.FrameNumber = View.Family->FrameNumber;
	FadingState.bIsVisible = bVisible;
	FadingState.bValid = true;
}

static void UpdatePrimitiveFading(const FScene& Scene, FViewInfo& View, FSceneViewState* ViewState, FPrimitiveRange PrimitiveRange)
{
	if (!ViewState)
	{
		return;
	}

	SCOPE_CYCLE_COUNTER(STAT_UpdatePrimitiveFading);

#if RHI_RAYTRACING
	const bool bRayTracingEnabled = IsRayTracingEnabled(View.GetShaderPlatform()) && View.IsRayTracingAllowedForView();
#endif 

	// Should we allow fading transitions at all this frame?  For frames where the camera moved
	// a large distance or where we haven't rendered a view in awhile, it's best to disable
	// fading so users don't see unexpected object transitions.
	if (!GDisableLODFade && !View.bDisableDistanceBasedFadeTransitions)
	{
		// Do a pass over potentially fading primitives and update their states.
		for (FSceneSetBitIterator BitIt(View.PotentiallyFadingPrimitiveMap, PrimitiveRange.StartIndex); BitIt.GetIndex() < PrimitiveRange.EndIndex; ++BitIt)
		{
			bool bVisible = View.PrimitiveVisibilityMap.AccessCorrespondingBit(BitIt);
			FPrimitiveFadingState& FadingState = ViewState->PrimitiveFadingStates.FindOrAdd(Scene.PrimitiveComponentIds[BitIt.GetIndex()]);
			UpdatePrimitiveFadingStateHelper(FadingState, View, bVisible);
			FRHIUniformBuffer* UniformBuffer = FadingState.UniformBuffer;
			if (UniformBuffer && !bVisible)
			{
				// If the primitive is fading out make sure it remains visible.
				View.PrimitiveVisibilityMap.AccessCorrespondingBit(BitIt) = true;

			#if RHI_RAYTRACING
				// Cannot just assume the ray tracing visibility will be true, so a complete recalculation for its culling needs to happen
				// This should be a very rare occurrence, so the hit is not worrisome.
				// TODO:  Could this be moved into the actual culling phase?

				if (bRayTracingEnabled && !ShouldCullForRayTracing(Scene, View, BitIt.GetIndex()))
				{
					View.PrimitiveRayTracingVisibilityMap.AccessCorrespondingBit(BitIt) = true;
				}
			#endif
			}
			View.PrimitiveFadeUniformBuffers[BitIt.GetIndex()] = UniformBuffer;
			View.PrimitiveFadeUniformBufferMap[BitIt.GetIndex()] = UniformBuffer != nullptr;
		}
	}
}

bool FViewInfo::UpdatePrimitiveFadingState(const FPrimitiveSceneInfo* PrimitiveSceneInfo, bool bFadingIn)
{
	// Update distance-based visibility and fading state if it has not already been updated.
	const int32 PrimitiveIndex = PrimitiveSceneInfo->GetIndex();
	const FRelativeBitReference PrimitiveBit(PrimitiveIndex);
	bool bStillFading = false;

	if (!PotentiallyFadingPrimitiveMap.AccessCorrespondingBit(PrimitiveBit))
	{
		FPrimitiveFadingState& FadingState = ((FSceneViewState*)State)->PrimitiveFadingStates.FindOrAdd(PrimitiveSceneInfo->PrimitiveComponentId);
		UpdatePrimitiveFadingStateHelper(FadingState, *this, bFadingIn);
		FRHIUniformBuffer* UniformBuffer = FadingState.UniformBuffer;
		bStillFading = UniformBuffer != nullptr;
		PrimitiveFadeUniformBuffers[PrimitiveIndex] = UniformBuffer;
		PrimitiveFadeUniformBufferMap[PrimitiveIndex] = UniformBuffer != nullptr;
		PotentiallyFadingPrimitiveMap.AccessCorrespondingBit(PrimitiveBit) = true;
	}

	// If we're still fading then make sure the object is still drawn, even if it's beyond the max draw distance
	return !bFadingIn && !bStillFading;
}

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

FFilterStaticMeshesForViewData::FFilterStaticMeshesForViewData(FViewInfo& View)
{
	ViewOrigin = View.ViewMatrices.GetViewOrigin();

	// outside of the loop to be more efficient
	ForcedLODLevel = (View.Family->EngineShowFlags.LOD) ? GetCVarForceLOD() : 0;

	LODScale = CVarStaticMeshLODDistanceScale.GetValueOnRenderThread() * View.LODDistanceFactor;

	MinScreenRadiusForDepthPrepassSquared = GMinScreenRadiusForDepthPrepass * GMinScreenRadiusForDepthPrepass;

	bFullEarlyZPass = ShouldForceFullDepthPass(View.GetShaderPlatform());
}

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

FDrawCommandRelevancePacket::FDrawCommandRelevancePacket()
{
	bUseCachedMeshDrawCommands = UseCachedMeshDrawCommands();

	for (int32 PassIndex = 0; PassIndex < EMeshPass::Num; ++PassIndex)
	{
		NumDynamicBuildRequestElements[PassIndex] = 0;
	}
}

void FDrawCommandRelevancePacket::AddCommandsForMesh(
	int32 PrimitiveIndex, 
	const FPrimitiveSceneInfo* InPrimitiveSceneInfo,
	const FStaticMeshBatchRelevance& RESTRICT StaticMeshRelevance, 
	const FStaticMeshBatch& RESTRICT StaticMesh, 
	EMeshDrawCommandCullingPayloadFlags CullingPayloadFlags,
	const FScene& Scene,
	bool bCanCache, 
	EMeshPass::Type PassType)
{
	const bool bIsNaniteMesh = Scene.PrimitiveFlagsCompact[PrimitiveIndex].bIsNaniteMesh;
	if (bIsNaniteMesh && Scene.PrimitivesAlwaysVisibleOffset != ~0u)
	{
		return;
	}

	const EShadingPath ShadingPath = GetFeatureLevelShadingPath(Scene.GetFeatureLevel());
	const bool bUseCachedMeshCommand = bUseCachedMeshDrawCommands
		&& !!(FPassProcessorManager::GetPassFlags(ShadingPath, PassType) & EMeshPassFlags::CachedMeshCommands)
		&& StaticMeshRelevance.bSupportsCachingMeshDrawCommands
		&& bCanCache;

	if (bUseCachedMeshCommand)
	{
		const int32 StaticMeshCommandInfoIndex = StaticMeshRelevance.GetStaticMeshCommandInfoIndex(PassType);
		if (StaticMeshCommandInfoIndex >= 0)
		{
			const FCachedMeshDrawCommandInfo& CachedMeshDrawCommand = InPrimitiveSceneInfo->StaticMeshCommandInfos[StaticMeshCommandInfoIndex];
			const FCachedPassMeshDrawList& SceneDrawList = Scene.CachedDrawLists[PassType];

			// AddUninitialized_GetRef()
			VisibleCachedDrawCommands[(uint32)PassType].AddUninitialized();
			FVisibleMeshDrawCommand& NewVisibleMeshDrawCommand = VisibleCachedDrawCommands[(uint32)PassType].Last();

			const FMeshDrawCommand* MeshDrawCommand = CachedMeshDrawCommand.StateBucketId >= 0
				? &Scene.CachedMeshDrawCommandStateBuckets[PassType].GetByElementId(CachedMeshDrawCommand.StateBucketId).Key
				: &SceneDrawList.MeshDrawCommands[CachedMeshDrawCommand.CommandIndex];

			NewVisibleMeshDrawCommand.Setup(
				MeshDrawCommand,
				InPrimitiveSceneInfo->GetMDCIdInfo(),
				CachedMeshDrawCommand.StateBucketId,
				CachedMeshDrawCommand.MeshFillMode,
				CachedMeshDrawCommand.MeshCullMode,
				CachedMeshDrawCommand.Flags,
				CachedMeshDrawCommand.SortKey,
				CachedMeshDrawCommand.CullingPayload,
				CullingPayloadFlags);
		}
	}
	else
	{
		NumDynamicBuildRequestElements[PassType] += StaticMeshRelevance.NumElements;
		DynamicBuildRequests[PassType].Add(&StaticMesh);
		DynamicBuildFlags[PassType].Add(CullingPayloadFlags);
	}
}

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

FRelevancePacket::FRelevancePacket(
	FVisibilityTaskData& InTaskData,
	const FViewInfo& InView,
	int32 InViewIndex,
	const FFilterStaticMeshesForViewData& InViewData,
	uint8* InMarkMasks,
	const UE::Tasks::FTask& InPrerequisitesTask)
	: CurrentWorldTime(InView.Family->Time.GetWorldTimeSeconds())
	, DeltaWorldTime(InView.Family->Time.GetDeltaWorldTimeSeconds())
	, TaskData(InTaskData)
	, TaskConfig(InTaskData.TaskConfig)
	, Scene(TaskData.Scene)
	, View(InView)
	, ViewCommands(TaskData.DynamicMeshElements.ViewCommandsPerView[InViewIndex])
	, ViewBit(1 << InViewIndex)
	, ViewData(InViewData)
	, DynamicPrimitiveViewMasks(TaskData.DynamicMeshElements.PrimitiveViewMasks)
	, MarkMasks(InMarkMasks)
	, PrerequisitesTask(InPrerequisitesTask)
	, Input(TaskConfig.Relevance.NumPrimitivesPerPacket)
	, NotDrawRelevant(TaskConfig.Relevance.NumPrimitivesPerPacket)
	, TranslucentSelfShadowPrimitives(TaskConfig.Relevance.NumPrimitivesPerPacket)
	, VisibleDynamicPrimitivesWithSimpleLights(TaskConfig.Relevance.NumPrimitivesPerPacket)
	, DirtyIndirectLightingCacheBufferPrimitives(TaskConfig.Relevance.NumPrimitivesPerPacket)
	, NaniteCustomDepthInstances(TaskConfig.Relevance.NumPrimitivesPerPacket)
	, PrimitivesLODMask(TaskConfig.Relevance.NumPrimitivesPerPacket)
	, bAddLightmapDensityCommands(TaskData.bAddLightmapDensityCommands)
{}

void FRelevancePacket::LaunchComputeRelevanceTask()
{
	check(!bComputeRelevanceTaskLaunched);

	if (!Input.IsEmpty())
	{
		bComputeRelevanceTaskLaunched = true;

		if (TaskData.DynamicMeshElements.CommandPipe)
		{
			TaskData.DynamicMeshElements.CommandPipe->AddNumCommands(1);
		}

		ComputeRelevanceTask = UE::Tasks::Launch(UE_SOURCE_LOCATION, [this]
		{
			FTaskTagScope Scope(ETaskTag::EParallelRenderingThread);
			FDynamicPrimitiveIndexList DynamicPrimitiveIndexList;
			ComputeRelevance(DynamicPrimitiveIndexList);

			if (TaskData.DynamicMeshElements.CommandPipe)
			{
				if (DynamicPrimitiveIndexList.IsEmpty())
				{
					TaskData.DynamicMeshElements.CommandPipe->ReleaseNumCommands(1);
				}
				else
				{
					TaskData.DynamicMeshElements.CommandPipe->EnqueueCommand(MoveTemp(DynamicPrimitiveIndexList));
				}
			}

		}, PrerequisitesTask, TaskConfig.Relevance.ComputeRelevanceTaskPriority);
	}
}

void FRelevancePacket::Finalize()
{
	FViewInfo& WriteView = const_cast<FViewInfo&>(View);
	FViewCommands& WriteViewCommands = const_cast<FViewCommands&>(ViewCommands);
	const EShadingPath ShadingPath = GetFeatureLevelShadingPath(Scene.GetFeatureLevel());

	for (int32 BitIndex : NotDrawRelevant.Prims)
	{
		WriteView.PrimitiveVisibilityMap[BitIndex] = false;
	}

	TaskConfig.Relevance.NumPrimitivesProcessed += Input.Prims.Num();

#if WITH_EDITOR
	WriteView.EditorVisualizeLevelInstancesNanite.Append(EditorVisualizeLevelInstancesNanite);
	WriteView.EditorSelectedInstancesNanite.Append(EditorSelectedInstancesNanite);
	WriteView.EditorSelectedInstancesNanite.Append(EditorOverlaidInstancesNanite);
	WriteView.EditorSelectedNaniteHitProxyIds.Append(EditorSelectedNaniteHitProxyIds);
#endif

	WriteView.ShadingModelMaskInView |= CombinedShadingModelMask;
	WriteView.bUsesGlobalDistanceField |= bUsesGlobalDistanceField;
	WriteView.bUsesLightingChannels |= bUsesLightingChannels;
	WriteView.bTranslucentSurfaceLighting |= bTranslucentSurfaceLighting;
	WriteView.bSceneHasSkyMaterial |= bSceneHasSkyMaterial;
	WriteView.bHasSingleLayerWaterMaterial |= bHasSingleLayerWaterMaterial;
	WriteView.bUsesSecondStageDepthPass |= bUsesSecondStageDepthPass && ShadingPath != EShadingPath::Mobile;
	VisibleDynamicPrimitivesWithSimpleLights.AppendTo(WriteView.VisibleDynamicPrimitivesWithSimpleLights);
	WriteView.NumVisibleDynamicPrimitives += NumVisibleDynamicPrimitives;
	WriteView.NumVisibleDynamicEditorPrimitives += NumVisibleDynamicEditorPrimitives;
	WriteView.TranslucentPrimCount.Append(TranslucentPrimCount);
	WriteView.bHasDistortionPrimitives |= bHasDistortionPrimitives;
	WriteView.bHasCustomDepthPrimitives |= bHasCustomDepthPrimitives;
	WriteView.CustomDepthStencilValues.Append(CustomDepthStencilValues);
	NaniteCustomDepthInstances.AppendTo(WriteView.NaniteCustomDepthInstances);
	WriteView.bUsesCustomDepth |= bUsesCustomDepth;
	WriteView.bUsesCustomStencil |= bUsesCustomStencil;
	WriteView.SubstrateViewData.MaxClosurePerPixel = FMath::Max(WriteView.SubstrateViewData.MaxClosurePerPixel, 8u - FMath::CountLeadingZeros8(SubstrateClosureCountMask));
	WriteView.SubstrateViewData.MaxBytesPerPixel = FMath::Max(WriteView.SubstrateViewData.MaxBytesPerPixel, SubstrateUintPerPixel * 4u);
	WriteView.SubstrateViewData.bUsesComplexSpecialRenderPath |= bUsesComplexSpecialRenderPath;
	DirtyIndirectLightingCacheBufferPrimitives.AppendTo(WriteView.DirtyIndirectLightingCacheBufferPrimitives);

	WriteView.VolumetricMeshBatches.Append(VolumetricMeshBatches);
	WriteView.HeterogeneousVolumesMeshBatches.Append(HeterogeneousVolumesMeshBatches);
	WriteView.SkyMeshBatches.Append(SkyMeshBatches);
	WriteView.SortedTrianglesMeshBatches.Append(SortedTrianglesMeshBatches);

	for (FPrimitiveLODMask PrimitiveLODMask : PrimitivesLODMask.Prims)
	{
		WriteView.PrimitivesLODMask[PrimitiveLODMask.PrimitiveIndex] = PrimitiveLODMask.LODMask;
	}

	for (int32 PassIndex = 0; PassIndex < EMeshPass::Num; PassIndex++)
	{
		if (PassIndex == EMeshPass::NaniteMeshPass && Scene.PrimitivesAlwaysVisibleOffset != ~0u)
		{
			continue;
		}

		FPassDrawCommandArray& SrcCommands = DrawCommandPacket.VisibleCachedDrawCommands[PassIndex];
		FMeshCommandOneFrameArray& DstCommands = WriteViewCommands.MeshCommands[PassIndex];
		if (SrcCommands.Num() > 0)
		{
			static_assert(sizeof(SrcCommands[0]) == sizeof(DstCommands[0]), "Memcpy sizes must match.");
			const int32 PrevNum = DstCommands.AddUninitialized(SrcCommands.Num());
			FMemory::Memcpy(&DstCommands[PrevNum], &SrcCommands[0], SrcCommands.Num() * sizeof(SrcCommands[0]));
		}

		FPassDrawCommandBuildRequestArray& SrcRequests = DrawCommandPacket.DynamicBuildRequests[PassIndex];
		TArray<const FStaticMeshBatch*, SceneRenderingAllocator>& DstRequests = WriteViewCommands.DynamicMeshCommandBuildRequests[PassIndex];
		if (SrcRequests.Num() > 0)
		{
			static_assert(sizeof(SrcRequests[0]) == sizeof(DstRequests[0]), "Memcpy sizes must match.");
			const int32 PrevNum = DstRequests.AddUninitialized(SrcRequests.Num());
			FMemory::Memcpy(&DstRequests[PrevNum], &SrcRequests[0], SrcRequests.Num() * sizeof(SrcRequests[0]));
		}

		FPassDrawCommandBuildFlagsArray& SrcFlags = DrawCommandPacket.DynamicBuildFlags[PassIndex];
		TArray<EMeshDrawCommandCullingPayloadFlags, SceneRenderingAllocator>& DstFlags = WriteViewCommands.DynamicMeshCommandBuildFlags[PassIndex];
		if (SrcFlags.Num() > 0)
		{
			static_assert(sizeof(SrcFlags[0]) == sizeof(DstFlags[0]), "Memcpy sizes must match.");
			const int32 PrevNum = DstFlags.AddUninitialized(SrcFlags.Num());
			FMemory::Memcpy(&DstFlags[PrevNum], &SrcFlags[0], SrcFlags.Num() * sizeof(SrcFlags[0]));
		}

		WriteViewCommands.NumDynamicMeshCommandBuildRequestElements[PassIndex] += DrawCommandPacket.NumDynamicBuildRequestElements[PassIndex];
	}

	// Prepare translucent self shadow uniform buffers.
	for (int32 PrimitiveIndex : TranslucentSelfShadowPrimitives.Prims)
	{
		FUniformBufferRHIRef& UniformBuffer = WriteView.TranslucentSelfShadowUniformBufferMap.FindOrAdd(PrimitiveIndex);

		if (!UniformBuffer)
		{
			FTranslucentSelfShadowUniformParameters Parameters;
			SetupTranslucentSelfShadowUniformParameters(nullptr, Parameters);
			UniformBuffer = FTranslucentSelfShadowUniformParameters::CreateUniformBuffer(Parameters, EUniformBufferUsage::UniformBuffer_SingleFrame);
		}
	}
}

void FRelevancePacket::ComputeRelevance(FDynamicPrimitiveIndexList& DynamicPrimitiveIndexList)
{
	TRACE_CPUPROFILER_EVENT_SCOPE(ComputeViewRelevance);
	SCOPE_CYCLE_COUNTER(STAT_ComputeViewRelevance);

	CombinedShadingModelMask = 0;
	SubstrateUintPerPixel = 0;
	bUsesComplexSpecialRenderPath = false;
	SubstrateClosureCountMask = 0;
	bSceneHasSkyMaterial = 0;
	bHasSingleLayerWaterMaterial = 0;
	bUsesSecondStageDepthPass = 0;
	bUsesGlobalDistanceField = false;
	bUsesLightingChannels = false;
	bTranslucentSurfaceLighting = false;
	const EShadingPath ShadingPath = GetFeatureLevelShadingPath(Scene.GetFeatureLevel());
	const bool bHairStrandsEnabled = IsHairStrandsEnabled(EHairStrandsShaderType::All, Scene.GetShaderPlatform());
	const bool bIsTLVUsingVoxelMarking = IsTranslucencyLightingVolumeUsingVoxelMarking();

	int32 NumVisibleStaticMeshElements = 0;
	FViewInfo& WriteView = const_cast<FViewInfo&>(View);
	const FSceneViewState* ViewState = (FSceneViewState*)View.State;
	const bool bMobileMaskedInEarlyPass = (ShadingPath == EShadingPath::Mobile) && Scene.EarlyZPassMode == DDM_MaskedOnly;
	const bool bMobileBasePassAlwaysUsesCSM = (ShadingPath == EShadingPath::Mobile) && MobileBasePassAlwaysUsesCSM(Scene.GetShaderPlatform());
	const bool bVelocityPassWritesDepth = Scene.EarlyZPassMode == DDM_AllOpaqueNoVelocity;
	const bool bIsTranslucentHoldoutEnabled = IsPrimitiveAlphaHoldoutEnabled(View);
	const bool bHLODActive = Scene.SceneLODHierarchy.IsActive();
	const FHLODVisibilityState* const HLODState = bHLODActive && ViewState ? &ViewState->HLODVisibilityState : nullptr;
	float MaxDrawDistanceScale = GetCachedScalabilityCVars().ViewDistanceScale;
	MaxDrawDistanceScale *= GetCachedScalabilityCVars().CalculateFieldOfViewDistanceScale(View.DesiredFOV);
	
	const auto AddEditorDynamicPrimitive = [this, &DynamicPrimitiveIndexList](int32 PrimitiveIndex)
	{
#if WITH_EDITOR
		if (GIsEditor)
		{
			++NumVisibleDynamicEditorPrimitives;

			if (DynamicPrimitiveViewMasks)
			{
				FPlatformAtomics::InterlockedOr((volatile int8*)&DynamicPrimitiveViewMasks->EditorPrimitives[PrimitiveIndex], ViewBit);
			}
			else
			{
				DynamicPrimitiveIndexList.EditorPrimitives.Emplace(PrimitiveIndex, ViewBit);
			}
		}
#endif
	};

	const auto AddDynamicPrimitive = [this, &DynamicPrimitiveIndexList](int32 PrimitiveIndex)
	{
		++NumVisibleDynamicPrimitives;

		if (DynamicPrimitiveViewMasks)
		{
			FPlatformAtomics::InterlockedOr((volatile int8*)&DynamicPrimitiveViewMasks->Primitives[PrimitiveIndex], ViewBit);
		}
		else
		{
			DynamicPrimitiveIndexList.Primitives.Emplace(PrimitiveIndex, ViewBit);
		}
	};

	for (int32 InputPrimsIndex = 0; InputPrimsIndex < Input.Prims.Num(); ++InputPrimsIndex)
	{
		int32 BitIndex = Input.Prims[InputPrimsIndex];

		if (InputPrimsIndex + 1 < Input.Prims.Num())
		{
			int32 NextBitIndex = Input.Prims[InputPrimsIndex + 1];

			// Prefetch the next primitive / proxy pair for the next loop.
			FPlatformMisc::Prefetch(Scene.Primitives[NextBitIndex]);
			FPlatformMisc::Prefetch(Scene.PrimitiveSceneProxies[NextBitIndex]);
		}

		FPrimitiveSceneInfo* PrimitiveSceneInfo = Scene.Primitives[BitIndex];
		FPrimitiveViewRelevance& ViewRelevance = const_cast<FPrimitiveViewRelevance&>(View.PrimitiveViewRelevanceMap[BitIndex]);

		const FPrimitiveSceneProxy* PrimitiveSceneProxy = PrimitiveSceneInfo->Proxy;

		// Prefetch the scene data and static mesh relevance array now while we call GetViewRelevance to reduce memory waits.
		FPlatformMisc::Prefetch(PrimitiveSceneInfo->StaticMeshRelevances.GetData());
		FPlatformMisc::Prefetch(PrimitiveSceneInfo->GetSceneData());

		ViewRelevance = PrimitiveSceneProxy->GetViewRelevance(&View);
		ViewRelevance.bInitializedThisFrame = true;

		const bool bStaticRelevance = ViewRelevance.bStaticRelevance;
		const bool bDrawRelevance = ViewRelevance.bDrawRelevance;
		const bool bDynamicRelevance = ViewRelevance.bDynamicRelevance;
		const bool bShadowRelevance = ViewRelevance.bShadowRelevance;
		const bool bEditorRelevance = ViewRelevance.bEditorPrimitiveRelevance;
		const bool bEditorVisualizeLevelInstanceRelevance = ViewRelevance.bEditorVisualizeLevelInstanceRelevance;
		const bool bEditorSelectionRelevance = ViewRelevance.bEditorStaticSelectionRelevance;
		const bool bTranslucentRelevance = ViewRelevance.HasTranslucency();
		const bool bHairStrandsRelevance = bHairStrandsEnabled && ViewRelevance.bHairStrands;

		if (View.bIsReflectionCapture && !PrimitiveSceneProxy->IsVisibleInReflectionCaptures())
		{
			NotDrawRelevant.AddPrim(BitIndex);
			continue;
		}

		if (bStaticRelevance && (bDrawRelevance || bShadowRelevance))
		{
			const FDesiredLODLevel DesiredLODLevel = PrimitiveSceneProxy->GetDesiredLODLevel_RenderThread(&View);

			int32 PrimitiveIndex = BitIndex;
			const FPrimitiveBounds& Bounds = Scene.PrimitiveBounds[PrimitiveIndex];
			const bool bIsPrimitiveDistanceCullFading = View.PrimitiveFadeUniformBufferMap[PrimitiveIndex];

			check(DesiredLODLevel.LOD >= 0);
			float MeshScreenSizeSquared = 0;

			FLODMask LODToRender;

			if (DesiredLODLevel.IsFixed())
			{
				LODToRender.SetLOD(DesiredLODLevel.LOD);
			}
			else
			{
				LODToRender = ComputeLODForMeshes(PrimitiveSceneInfo->StaticMeshRelevances, View, Bounds.BoxSphereBounds.Origin, Bounds.BoxSphereBounds.SphereRadius, PrimitiveSceneInfo->GpuLodInstanceRadius, ViewData.ForcedLODLevel, MeshScreenSizeSquared, DesiredLODLevel.LOD, ViewData.LODScale);
			}

			PrimitivesLODMask.AddPrim(FRelevancePacket::FPrimitiveLODMask(PrimitiveIndex, LODToRender));

			const bool bIsHLODFading = HLODState ? HLODState->IsNodeFading(PrimitiveIndex) : false;
			const bool bIsHLODFadingOut = HLODState ? HLODState->IsNodeFadingOut(PrimitiveIndex) : false;
			const bool bIsLODDithered = LODToRender.IsDithered();
			const bool bIsLODRange = LODToRender.IsLODRange();

			float DistanceSquared = (Bounds.BoxSphereBounds.Origin - ViewData.ViewOrigin).SizeSquared();
			const float LODFactorDistanceSquared = DistanceSquared * FMath::Square(ViewData.LODScale);
			const bool bDrawDepthOnly = ViewData.bFullEarlyZPass || ((ShadingPath != EShadingPath::Mobile) && (FMath::Square(Bounds.BoxSphereBounds.SphereRadius) > GMinScreenRadiusForDepthPrepass * GMinScreenRadiusForDepthPrepass * LODFactorDistanceSquared));

			const int32 NumStaticMeshes = PrimitiveSceneInfo->StaticMeshRelevances.Num();
			for (int32 MeshIndex = 0; MeshIndex < NumStaticMeshes; MeshIndex++)
			{
				const FStaticMeshBatchRelevance& StaticMeshRelevance = PrimitiveSceneInfo->StaticMeshRelevances[MeshIndex];
				const FStaticMeshBatch& StaticMesh = PrimitiveSceneInfo->StaticMeshes[MeshIndex];

				if (StaticMeshRelevance.bOverlayMaterial && !View.Family->EngineShowFlags.DistanceCulledPrimitives)
				{
					// Overlay mesh can have its own cull distance that is shorter than primitive cull distance
					float OverlayMaterialMaxDrawDistance = StaticMeshRelevance.ScreenSize;
					if (OverlayMaterialMaxDrawDistance > 0.f && OverlayMaterialMaxDrawDistance != FLT_MAX)
					{
						if (DistanceSquared > FMath::Square(OverlayMaterialMaxDrawDistance * MaxDrawDistanceScale))
						{
							// distance culled
							continue;
						}
					}
				}

				int8 StaticMeshLODIndex = StaticMeshRelevance.GetLODIndex();
				if (LODToRender.ContainsLOD(StaticMeshLODIndex))
				{
					uint8 MarkMask = 0;
					bool bHiddenByHLODFade = false; // Hide mesh LOD levels that HLOD is substituting

					if (bIsHLODFading)
					{
						if (bIsHLODFadingOut)
						{
							if (bIsLODDithered && LODToRender.LODIndex1 == StaticMeshLODIndex)
							{
								bHiddenByHLODFade = true;
							}
							else
							{
								MarkMask |= EMarkMaskBits::StaticMeshFadeOutDitheredLODMapMask;
							}
						}
						else
						{
							if (bIsLODDithered && LODToRender.LODIndex0 == StaticMeshLODIndex)
							{
								bHiddenByHLODFade = true;
							}
							else
							{
								MarkMask |= EMarkMaskBits::StaticMeshFadeInDitheredLODMapMask;
							}
						}
					}
					else if (bIsLODDithered)
					{
						if (LODToRender.LODIndex0 == StaticMeshLODIndex)
						{
							MarkMask |= EMarkMaskBits::StaticMeshFadeOutDitheredLODMapMask;
						}
						else
						{
							MarkMask |= EMarkMaskBits::StaticMeshFadeInDitheredLODMapMask;
						}
					}

					// Don't cache if it requires per view per mesh state for LOD dithering or distance cull fade.
					const bool bIsMeshDitheringLOD = StaticMeshRelevance.bDitheredLODTransition && (MarkMask & (EMarkMaskBits::StaticMeshFadeOutDitheredLODMapMask | EMarkMaskBits::StaticMeshFadeInDitheredLODMapMask));
					const bool bCanCache = !bIsPrimitiveDistanceCullFading && !bIsMeshDitheringLOD;

					// When we apply LOD selection on GPU we submit a range of LODs and then cull each one according to screen size.
					// At both ends of a LOD range we only want to cull by screen size in one direction. This ensures that all possible screen sizes map to one LOD in the range.
					EMeshDrawCommandCullingPayloadFlags CullingPayloadFlags = EMeshDrawCommandCullingPayloadFlags::Default;
					CullingPayloadFlags |= bIsLODRange && !LODToRender.IsMaxLODInRange(StaticMeshRelevance.GetLODIndex()) ? EMeshDrawCommandCullingPayloadFlags::MinScreenSizeCull : (EMeshDrawCommandCullingPayloadFlags)0;
					CullingPayloadFlags |= bIsLODRange && !LODToRender.IsMinLODInRange(StaticMeshRelevance.GetLODIndex()) ? EMeshDrawCommandCullingPayloadFlags::MaxScreenSizeCull : (EMeshDrawCommandCullingPayloadFlags)0;

					if (ViewRelevance.bDrawRelevance)
					{
						if ((StaticMeshRelevance.bUseForMaterial || StaticMeshRelevance.bUseAsOccluder)
							&& (ViewRelevance.bRenderInMainPass || ViewRelevance.bRenderCustomDepth || ViewRelevance.bRenderInDepthPass)
							&& !bHiddenByHLODFade)
						{
							// Add velocity commands first to track for case where velocity pass writes depth.
							bool bIsMeshInVelocityPass = false;
							if (StaticMeshRelevance.bUseForMaterial && ViewRelevance.bRenderInMainPass)
							{
								if (ViewRelevance.HasVelocity())
								{
									if (FVelocityMeshProcessor::PrimitiveHasVelocityForView(View, PrimitiveSceneProxy))
									{
										if (ViewRelevance.bVelocityRelevance &&
											FOpaqueVelocityMeshProcessor::PrimitiveCanHaveVelocity(View.GetShaderPlatform(), PrimitiveSceneProxy) &&
											FOpaqueVelocityMeshProcessor::PrimitiveHasVelocityForFrame(PrimitiveSceneProxy))
										{
											DrawCommandPacket.AddCommandsForMesh(PrimitiveIndex, PrimitiveSceneInfo, StaticMeshRelevance, StaticMesh, CullingPayloadFlags, Scene, bCanCache, EMeshPass::Velocity);
											bIsMeshInVelocityPass = true;
										}

										if (ViewRelevance.bOutputsTranslucentVelocity &&
											FTranslucentVelocityMeshProcessor::PrimitiveCanHaveVelocity(View.GetShaderPlatform(), PrimitiveSceneProxy) &&
											FTranslucentVelocityMeshProcessor::PrimitiveHasVelocityForFrame(PrimitiveSceneProxy))
										{
											DrawCommandPacket.AddCommandsForMesh(PrimitiveIndex, PrimitiveSceneInfo, StaticMeshRelevance, StaticMesh, CullingPayloadFlags, Scene, bCanCache, EMeshPass::TranslucentVelocity);
										}
									}
								}
							}

							// Add depth commands.
							if (StaticMeshRelevance.bUseForDepthPass && (bDrawDepthOnly || (bMobileMaskedInEarlyPass && ViewRelevance.bMasked)))
							{
								if (!(bIsMeshInVelocityPass && bVelocityPassWritesDepth))
								{
									if (ViewRelevance.bRenderInSecondStageDepthPass && ShadingPath != EShadingPath::Mobile)
									{
										DrawCommandPacket.AddCommandsForMesh(PrimitiveIndex, PrimitiveSceneInfo, StaticMeshRelevance, StaticMesh, CullingPayloadFlags, Scene, bCanCache, EMeshPass::SecondStageDepthPass);
									}
									else
									{
										DrawCommandPacket.AddCommandsForMesh(PrimitiveIndex, PrimitiveSceneInfo, StaticMeshRelevance, StaticMesh, CullingPayloadFlags, Scene, bCanCache, EMeshPass::DepthPass);
									}
								}
#if RHI_RAYTRACING
								// Only used by ray traced shadows
								if (IsRayTracingEnabled() && View.bHasRayTracingShadows && View.IsRayTracingAllowedForView())
								{
									if (MarkMask & EMarkMaskBits::StaticMeshFadeOutDitheredLODMapMask)
									{
										DrawCommandPacket.AddCommandsForMesh(PrimitiveIndex, PrimitiveSceneInfo, StaticMeshRelevance, StaticMesh, CullingPayloadFlags, Scene, bCanCache, EMeshPass::DitheredLODFadingOutMaskPass);
									}
								}
#endif
							}

							// Mark static mesh as visible for rendering
							if (StaticMeshRelevance.bUseForMaterial && (ViewRelevance.bRenderInMainPass || ViewRelevance.bRenderCustomDepth))
							{
								// Specific logic for mobile packets
								if (ShadingPath == EShadingPath::Mobile)
								{
									// Skydome must not be added to base pass bucket
									if (!StaticMeshRelevance.bUseSkyMaterial)
									{
										DrawCommandPacket.AddCommandsForMesh(PrimitiveIndex, PrimitiveSceneInfo, StaticMeshRelevance, StaticMesh, CullingPayloadFlags, Scene, bCanCache, EMeshPass::BasePass);
										if (!bMobileBasePassAlwaysUsesCSM)
										{
											DrawCommandPacket.AddCommandsForMesh(PrimitiveIndex, PrimitiveSceneInfo, StaticMeshRelevance, StaticMesh, CullingPayloadFlags, Scene, bCanCache, EMeshPass::MobileBasePassCSM);
										}
									}
									else
									{
										DrawCommandPacket.AddCommandsForMesh(PrimitiveIndex, PrimitiveSceneInfo, StaticMeshRelevance, StaticMesh, CullingPayloadFlags, Scene, bCanCache, EMeshPass::SkyPass);
									}
									// bUseSingleLayerWaterMaterial is added to BasePass on Mobile. No need to add it to SingleLayerWaterPass

									MarkMask |= EMarkMaskBits::StaticMeshVisibilityMapMask;
								}
								else // Regular shading path
								{
									DrawCommandPacket.AddCommandsForMesh(PrimitiveIndex, PrimitiveSceneInfo, StaticMeshRelevance, StaticMesh, CullingPayloadFlags, Scene, bCanCache, EMeshPass::BasePass);
									MarkMask |= EMarkMaskBits::StaticMeshVisibilityMapMask;

									if (StaticMeshRelevance.bUseSkyMaterial)
									{
										DrawCommandPacket.AddCommandsForMesh(PrimitiveIndex, PrimitiveSceneInfo, StaticMeshRelevance, StaticMesh, CullingPayloadFlags, Scene, bCanCache, EMeshPass::SkyPass);
									}
									if (StaticMeshRelevance.bUseSingleLayerWaterMaterial)
									{
										DrawCommandPacket.AddCommandsForMesh(PrimitiveIndex, PrimitiveSceneInfo, StaticMeshRelevance, StaticMesh, CullingPayloadFlags, Scene, bCanCache, EMeshPass::SingleLayerWaterPass);
										DrawCommandPacket.AddCommandsForMesh(PrimitiveIndex, PrimitiveSceneInfo, StaticMeshRelevance, StaticMesh, CullingPayloadFlags, Scene, bCanCache, EMeshPass::SingleLayerWaterDepthPrepass);
									}
								}

								if (StaticMeshRelevance.bUseAnisotropy)
								{
									DrawCommandPacket.AddCommandsForMesh(PrimitiveIndex, PrimitiveSceneInfo, StaticMeshRelevance, StaticMesh, CullingPayloadFlags, Scene, bCanCache, EMeshPass::AnisotropyPass);
								}

								if (ViewRelevance.bRenderCustomDepth)
								{
									DrawCommandPacket.AddCommandsForMesh(PrimitiveIndex, PrimitiveSceneInfo, StaticMeshRelevance, StaticMesh, CullingPayloadFlags, Scene, bCanCache, EMeshPass::CustomDepth);
								}

								if (bAddLightmapDensityCommands)
								{
									DrawCommandPacket.AddCommandsForMesh(PrimitiveIndex, PrimitiveSceneInfo, StaticMeshRelevance, StaticMesh, CullingPayloadFlags, Scene, bCanCache, EMeshPass::LightmapDensity);
								}
#if !(UE_BUILD_SHIPPING || UE_BUILD_TEST)
								else if (View.Family->UseDebugViewPS())
								{
									DrawCommandPacket.AddCommandsForMesh(PrimitiveIndex, PrimitiveSceneInfo, StaticMeshRelevance, StaticMesh, CullingPayloadFlags, Scene, bCanCache, EMeshPass::DebugViewMode);
								}
#endif

#if WITH_EDITOR
								if (StaticMeshRelevance.bSelectable)
								{
									if (View.bAllowTranslucentPrimitivesInHitProxy)
									{
										DrawCommandPacket.AddCommandsForMesh(PrimitiveIndex, PrimitiveSceneInfo, StaticMeshRelevance, StaticMesh, CullingPayloadFlags, Scene, bCanCache, EMeshPass::HitProxy);
									}
									else
									{
										DrawCommandPacket.AddCommandsForMesh(PrimitiveIndex, PrimitiveSceneInfo, StaticMeshRelevance, StaticMesh, CullingPayloadFlags, Scene, bCanCache, EMeshPass::HitProxyOpaqueOnly);
									}
								}
#endif
								++NumVisibleStaticMeshElements;

								INC_DWORD_STAT_BY(STAT_StaticMeshTriangles, StaticMesh.GetNumPrimitives());
							}
						}

						if (StaticMeshRelevance.bUseForMaterial
							&& ViewRelevance.HasTranslucency()
							&& !ViewRelevance.bEditorPrimitiveRelevance
							&& ViewRelevance.bRenderInMainPass)
						{
							if (View.Family->AllowTranslucencyAfterDOF())
							{
								if ((ViewRelevance.bNormalTranslucency || (View.AutoBeforeDOFTranslucencyBoundary > 0.0f && ViewRelevance.bSeparateTranslucency)))
								{
									DrawCommandPacket.AddCommandsForMesh(PrimitiveIndex, PrimitiveSceneInfo, StaticMeshRelevance, StaticMesh, CullingPayloadFlags, Scene, bCanCache, EMeshPass::TranslucencyStandard);
								}

								if ((ViewRelevance.bNormalTranslucency || (View.AutoBeforeDOFTranslucencyBoundary > 0.0f && ViewRelevance.bSeparateTranslucency)) && ViewRelevance.bTranslucencyModulate && View.Family->AllowStandardTranslucencySeparated())
								{
									DrawCommandPacket.AddCommandsForMesh(PrimitiveIndex, PrimitiveSceneInfo, StaticMeshRelevance, StaticMesh, CullingPayloadFlags, Scene, bCanCache, EMeshPass::TranslucencyStandardModulate);
								}

								if (ViewRelevance.bSeparateTranslucency)
								{
									DrawCommandPacket.AddCommandsForMesh(PrimitiveIndex, PrimitiveSceneInfo, StaticMeshRelevance, StaticMesh, CullingPayloadFlags, Scene, bCanCache, EMeshPass::TranslucencyAfterDOF);
								}

								if (ViewRelevance.bSeparateTranslucency && ViewRelevance.bTranslucencyModulate)
								{
									DrawCommandPacket.AddCommandsForMesh(PrimitiveIndex, PrimitiveSceneInfo, StaticMeshRelevance, StaticMesh, CullingPayloadFlags, Scene, bCanCache, EMeshPass::TranslucencyAfterDOFModulate);
								}

								if (ViewRelevance.bPostMotionBlurTranslucency)
								{
									DrawCommandPacket.AddCommandsForMesh(PrimitiveIndex, PrimitiveSceneInfo, StaticMeshRelevance, StaticMesh, CullingPayloadFlags, Scene, bCanCache, EMeshPass::TranslucencyAfterMotionBlur);
								}
							}
							else
							{
								// Otherwise, everything is rendered in a single bucket. This is not related to whether DOF is currently enabled or not.
								// When using all translucency, Standard and AfterDOF are sorted together instead of being rendered like 2 buckets.
								DrawCommandPacket.AddCommandsForMesh(PrimitiveIndex, PrimitiveSceneInfo, StaticMeshRelevance, StaticMesh, CullingPayloadFlags, Scene, bCanCache, EMeshPass::TranslucencyAll);
							}

							if (bIsTranslucentHoldoutEnabled)
							{
								DrawCommandPacket.AddCommandsForMesh(PrimitiveIndex, PrimitiveSceneInfo, StaticMeshRelevance, StaticMesh, CullingPayloadFlags, Scene, bCanCache, EMeshPass::TranslucencyHoldout);
							}

							if (ViewRelevance.bTranslucentSurfaceLighting || bIsTLVUsingVoxelMarking)
							{
								DrawCommandPacket.AddCommandsForMesh(PrimitiveIndex, PrimitiveSceneInfo, StaticMeshRelevance, StaticMesh, CullingPayloadFlags, Scene, bCanCache, EMeshPass::LumenTranslucencyRadianceCacheMark);
							}

							if (ViewRelevance.bTranslucentSurfaceLighting)
							{
								DrawCommandPacket.AddCommandsForMesh(PrimitiveIndex, PrimitiveSceneInfo, StaticMeshRelevance, StaticMesh, CullingPayloadFlags, Scene, bCanCache, EMeshPass::LumenFrontLayerTranslucencyGBuffer);
							}

							if (ViewRelevance.bDistortion)
							{
								DrawCommandPacket.AddCommandsForMesh(PrimitiveIndex, PrimitiveSceneInfo, StaticMeshRelevance, StaticMesh, CullingPayloadFlags, Scene, bCanCache, EMeshPass::Distortion);
							}
						}

#if WITH_EDITOR
						if (ViewRelevance.bEditorVisualizeLevelInstanceRelevance)
						{
							DrawCommandPacket.AddCommandsForMesh(PrimitiveIndex, PrimitiveSceneInfo, StaticMeshRelevance, StaticMesh, CullingPayloadFlags, Scene, bCanCache, EMeshPass::EditorLevelInstance);
						}

						if (ViewRelevance.bEditorStaticSelectionRelevance)
						{
							DrawCommandPacket.AddCommandsForMesh(PrimitiveIndex, PrimitiveSceneInfo, StaticMeshRelevance, StaticMesh, CullingPayloadFlags, Scene, bCanCache, EMeshPass::EditorSelection);
						}
#endif

						if (ViewRelevance.bHasVolumeMaterialDomain)
						{
							if (ShouldRenderMeshBatchWithHeterogeneousVolumes(&StaticMesh, PrimitiveSceneProxy, View.FeatureLevel))
							{
								HeterogeneousVolumesMeshBatches.AddUninitialized(1);
								FVolumetricMeshBatch& BatchAndProxy = HeterogeneousVolumesMeshBatches.Last();
								BatchAndProxy.Mesh = &StaticMesh;
								BatchAndProxy.Proxy = PrimitiveSceneProxy;
							}
							else
							{
								VolumetricMeshBatches.AddUninitialized(1);
								FVolumetricMeshBatch& BatchAndProxy = VolumetricMeshBatches.Last();
								BatchAndProxy.Mesh = &StaticMesh;
								BatchAndProxy.Proxy = PrimitiveSceneProxy;
							}
						}

						if (ViewRelevance.bUsesSkyMaterial)
						{
							SkyMeshBatches.AddUninitialized(1);
							FSkyMeshBatch& BatchAndProxy = SkyMeshBatches.Last();
							BatchAndProxy.Mesh = &StaticMesh;
							BatchAndProxy.Proxy = PrimitiveSceneProxy;
							BatchAndProxy.bVisibleInMainPass = ViewRelevance.bRenderInMainPass;
							BatchAndProxy.bVisibleInRealTimeSkyCapture = PrimitiveSceneInfo->bVisibleInRealTimeSkyCapture;
						}

						if (ViewRelevance.HasTranslucency() && PrimitiveSceneProxy->SupportsSortedTriangles()) // Need to check material as well
						{
							SortedTrianglesMeshBatches.AddUninitialized(1);
							FSortedTrianglesMeshBatch& BatchAndProxy = SortedTrianglesMeshBatches.Last();
							BatchAndProxy.Mesh = &StaticMesh;
							BatchAndProxy.Proxy = PrimitiveSceneProxy;
						}

						// FIXME: Now if a primitive has one batch with a decal material all primitive mesh batches will be added as decals
						// Because ViewRelevance is a sum of all material relevances in the primitive
						if (ViewRelevance.bRenderInMainPass && ViewRelevance.bDecal && StaticMeshRelevance.bUseForMaterial)
						{
							for (uint8 DecalRenderTargetMode = 0; DecalRenderTargetMode < (uint8)EDecalRenderTargetMode::Num; ++DecalRenderTargetMode)
							{
								if (DecalRendering::IsCompatibleWithRenderTargetMode(StaticMeshRelevance.DecalRenderTargetModeMask, (EDecalRenderTargetMode)DecalRenderTargetMode))
								{
									EMeshPass::Type DecalMeshPassType = DecalRendering::GetMeshPassType((EDecalRenderTargetMode)DecalRenderTargetMode);
									DrawCommandPacket.AddCommandsForMesh(PrimitiveIndex, PrimitiveSceneInfo, StaticMeshRelevance, StaticMesh, CullingPayloadFlags, Scene, bCanCache, DecalMeshPassType);
								}
							}
						}
					}

					if (MarkMask)
					{
						MarkMasks[StaticMeshRelevance.Id] = MarkMask;
					}
				}
			}
		}

		if (!bDrawRelevance)
		{
			NotDrawRelevant.AddPrim(BitIndex);
			continue;
		}

#if WITH_EDITOR
		auto CollectNaniteInstanceDraws = [](
			const FPrimitiveSceneInfo& PrimitiveSceneInfo,
			const FPrimitiveSceneProxy* PrimitiveSceneProxy,
			TArray<Nanite::FInstanceDraw>& OutSelectedInstanceDraws,
			TArray<Nanite::FInstanceDraw>* OutOverlaidInstanceDraws,
			TArray<uint32>* OutSelectedInstanceHitProxyIDs,
			bool bSelectedInstancesOnly
		)
		{
			if (!PrimitiveSceneProxy->IsNaniteMesh())
			{
				return;
			}

			auto* NaniteProxy = static_cast<const Nanite::FSceneProxyBase*>(PrimitiveSceneProxy);

			if (bSelectedInstancesOnly)
			{
				if (!NaniteProxy->IsSelected() && !NaniteProxy->WantsEditorEffects())
				{
					// We're only concerned with selected instances or those with editor effects
					return;
				}
				if (NaniteProxy->IsSelected() && !NaniteProxy->HasSelectedInstances() && OutSelectedInstanceHitProxyIDs != nullptr)
				{
					// Primitive is selected but not individual instances, so just add the primitive's hit proxy IDs
					for (auto& HitProxyId : NaniteProxy->GetHitProxyIds())
					{
						const uint32 HitProxyID = HitProxyId.GetColor().ToPackedABGR();
						OutSelectedInstanceHitProxyIDs->Add(HitProxyID);
					}
				}
			}

			const FInstanceSceneDataBuffers* InstanceSceneDataBuffers = PrimitiveSceneInfo.GetInstanceSceneDataBuffers();
			const bool bCollectInstanceHitProxyIds = bSelectedInstancesOnly &&
				NaniteProxy->HasSelectedInstances() &&
				OutSelectedInstanceHitProxyIDs != nullptr &&
				InstanceSceneDataBuffers != nullptr &&
				!InstanceSceneDataBuffers->IsInstanceDataGPUOnly();
			const bool bOverlaidDraws = OutOverlaidInstanceDraws &&
				NaniteProxy->WantsEditorEffects() &&
				!NaniteProxy->IsSelected();
			
			const int32 MaxInstances = PrimitiveSceneInfo.GetNumInstanceSceneDataEntries();
			TArray<Nanite::FInstanceDraw>& OutDrawArray = bOverlaidDraws ? *OutOverlaidInstanceDraws : OutSelectedInstanceDraws;
			OutDrawArray.Reserve(OutDrawArray.Num() + MaxInstances);

			for (int32 Idx = 0; Idx < MaxInstances; ++Idx)
			{
				if (bCollectInstanceHitProxyIds)
				{
					FInstanceSceneDataBuffers::FReadView ProxyData = InstanceSceneDataBuffers->GetReadView();
					// If we have per-instance editor data, exclude instance draws of unselected instances
					// draws of unselected instances
					if (ProxyData.InstanceEditorData.IsValidIndex(Idx))
					{
						FColor HitProxyColor;
						bool bSelected;
						FInstanceEditorData::Unpack(ProxyData.InstanceEditorData[Idx], HitProxyColor, bSelected);
						if (!bSelected)
						{
							continue;
						}
							
						const uint32 HitProxyID = HitProxyColor.ToPackedABGR();
						OutSelectedInstanceHitProxyIDs->Add(HitProxyID);
					}
				}

				OutDrawArray.Add(
					Nanite::FInstanceDraw {
						uint32(PrimitiveSceneInfo.GetInstanceSceneDataOffset() + Idx),
						0u
					}
				);
			}
		};

		if (bEditorVisualizeLevelInstanceRelevance)
		{
			CollectNaniteInstanceDraws(*PrimitiveSceneInfo, PrimitiveSceneProxy, EditorVisualizeLevelInstancesNanite, nullptr, nullptr, false);
		}

		if (bEditorSelectionRelevance)
		{
			CollectNaniteInstanceDraws(*PrimitiveSceneInfo, PrimitiveSceneProxy, EditorSelectedInstancesNanite, &EditorOverlaidInstancesNanite, &EditorSelectedNaniteHitProxyIds, true);
		}
#endif

		if (bEditorRelevance)
		{
			AddEditorDynamicPrimitive(BitIndex);
		}
		else if(bDynamicRelevance)
		{
			AddDynamicPrimitive(BitIndex);

			if (ViewRelevance.bHasSimpleLights)
			{
				VisibleDynamicPrimitivesWithSimpleLights.AddPrim(PrimitiveSceneInfo);
			}
		}
		// Filter with !bStaticRelevance to avoid regular/non-strands geometry to be added two times.
		else if (!bStaticRelevance && bHairStrandsRelevance)
		{
			AddDynamicPrimitive(BitIndex);
		}

		if (bTranslucentRelevance && !bEditorRelevance && ViewRelevance.bRenderInMainPass)
		{
			if (View.Family->AllowTranslucencyAfterDOF())
			{
				if ((ViewRelevance.bNormalTranslucency || (View.AutoBeforeDOFTranslucencyBoundary > 0.0f && ViewRelevance.bSeparateTranslucency)))
				{
					TranslucentPrimCount.Add(ETranslucencyPass::TPT_TranslucencyStandard, ViewRelevance.bUsesSceneColorCopy);
				}

				if ((ViewRelevance.bNormalTranslucency || (View.AutoBeforeDOFTranslucencyBoundary > 0.0f && ViewRelevance.bSeparateTranslucency)) && ViewRelevance.bTranslucencyModulate && View.Family->AllowStandardTranslucencySeparated())
				{
					TranslucentPrimCount.Add(ETranslucencyPass::TPT_TranslucencyStandardModulate, ViewRelevance.bUsesSceneColorCopy);
				}

				if (ViewRelevance.bSeparateTranslucency)
				{
					TranslucentPrimCount.Add(ETranslucencyPass::TPT_TranslucencyAfterDOF, ViewRelevance.bUsesSceneColorCopy);
				}

				if (ViewRelevance.bSeparateTranslucency && ViewRelevance.bTranslucencyModulate)
				{
					TranslucentPrimCount.Add(ETranslucencyPass::TPT_TranslucencyAfterDOFModulate, ViewRelevance.bUsesSceneColorCopy);
				}

				if (ViewRelevance.bPostMotionBlurTranslucency)
				{
					TranslucentPrimCount.Add(ETranslucencyPass::TPT_TranslucencyAfterMotionBlur, ViewRelevance.bUsesSceneColorCopy);
				}
			}
			else // Otherwise, everything is rendered in a single bucket. This is not related to whether DOF is currently enabled or not.
			{
				// When using all translucency, Standard and AfterDOF are sorted together instead of being rendered like 2 buckets.
				TranslucentPrimCount.Add(ETranslucencyPass::TPT_AllTranslucency, ViewRelevance.bUsesSceneColorCopy);
			}
			
			if (bIsTranslucentHoldoutEnabled)
			{
				TranslucentPrimCount.Add(ETranslucencyPass::TPT_TranslucencyHoldout, true); // use scene copy
			}

			if (ViewRelevance.bDistortion)
			{
				bHasDistortionPrimitives = true;
			}
		}

		CombinedShadingModelMask |= ViewRelevance.ShadingModelMask;
		SubstrateUintPerPixel = FMath::Max(SubstrateUintPerPixel, ViewRelevance.SubstrateUintPerPixel);
		bUsesComplexSpecialRenderPath |= ViewRelevance.bUsesComplexSpecialRenderPath;
		SubstrateClosureCountMask |= ViewRelevance.SubstrateClosureCountMask;
		bUsesGlobalDistanceField |= ViewRelevance.bUsesGlobalDistanceField;
		bUsesLightingChannels |= ViewRelevance.bUsesLightingChannels;
		bTranslucentSurfaceLighting |= ViewRelevance.bTranslucentSurfaceLighting;
		bUsesCustomDepth |= (ViewRelevance.CustomDepthStencilUsageMask & 1) > 0;
		bUsesCustomStencil |= (ViewRelevance.CustomDepthStencilUsageMask & (1 << 1)) > 0;
		bSceneHasSkyMaterial |= ViewRelevance.bUsesSkyMaterial;
		bHasSingleLayerWaterMaterial |= ViewRelevance.bUsesSingleLayerWaterMaterial;
		bUsesSecondStageDepthPass |= ViewRelevance.bRenderInSecondStageDepthPass && ShadingPath!=EShadingPath::Mobile;

		if (ViewRelevance.bRenderCustomDepth)
		{
			bHasCustomDepthPrimitives = true;
			CustomDepthStencilValues.Add(PrimitiveSceneInfo->Proxy->GetCustomDepthStencilValue());

			if (PrimitiveSceneInfo->Proxy->IsNaniteMesh())
			{
				check(PrimitiveSceneInfo->IsIndexValid());
				NaniteCustomDepthInstances.AddPrim(
					FPrimitiveInstanceRange {
						PrimitiveSceneInfo->GetIndex(),
						PrimitiveSceneInfo->GetInstanceSceneDataOffset(),
						PrimitiveSceneInfo->GetNumInstanceSceneDataEntries()
					}
				);
			}
		}

		extern bool GUseTranslucencyShadowDepths;
		if (GUseTranslucencyShadowDepths && ViewRelevance.bTranslucentSelfShadow)
		{
			TranslucentSelfShadowPrimitives.AddPrim(BitIndex);
		}

		PrimitiveSceneInfo->LastRenderTime = CurrentWorldTime;

		// Update the last component render time only if we know for certain the primitive is un-occluded.
		if (View.PrimitiveDefinitelyUnoccludedMap[BitIndex] || View.Family->EngineShowFlags.Wireframe)
		{
			const bool bUpdateLastRenderTimeOnScreen = true;
			PrimitiveSceneInfo->UpdateComponentLastRenderTime(CurrentWorldTime, bUpdateLastRenderTimeOnScreen);
		}

		// Cache the nearest reflection proxy if needed
		if (PrimitiveSceneInfo->NeedsReflectionCaptureUpdate())
		{
			// mobile should not have any outstanding reflection capture update requests at this point, except for when lighting isn't rebuilt		
			PrimitiveSceneInfo->CacheReflectionCaptures();
		}

		if (PrimitiveSceneInfo->NeedsIndirectLightingCacheBufferUpdate())
		{
			DirtyIndirectLightingCacheBufferPrimitives.AddPrim(PrimitiveSceneInfo);
		}
	}

	static_assert(sizeof(WriteView.NumVisibleStaticMeshElements) == sizeof(int32), "Atomic is the wrong size");
	FPlatformAtomics::InterlockedAdd((volatile int32*)&WriteView.NumVisibleStaticMeshElements, NumVisibleStaticMeshElements);
}

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

FComputeAndMarkRelevance::FComputeAndMarkRelevance(FVisibilityTaskData& InTaskData, FScene& InScene, FViewInfo& InView, uint8 InViewIndex, const UE::Tasks::FTask& InPrerequisitesTask)
	: TaskData(InTaskData)
	, Scene(InScene)
	, View(InView)
	, ViewCommands(TaskData.DynamicMeshElements.ViewCommandsPerView[InViewIndex])
	, ViewIndex(InViewIndex)
	, ViewData(View)
	, NumMeshes(Scene.StaticMeshes.GetMaxIndex())
	, NumPrimitivesPerPacket(InTaskData.TaskConfig.Relevance.NumPrimitivesPerPacket)
	, PrerequisitesTask(InPrerequisitesTask)
	, bLaunchOnAddPrimitive(TaskData.TaskConfig.Schedule == EVisibilityTaskSchedule::Parallel)
	, bFinished(!bLaunchOnAddPrimitive)
{
	MarkMasks = (uint8*)TaskData.Allocator.Malloc(NumMeshes + 31, 8); // some padding to simplify the high speed transpose
	FMemory::Memzero(MarkMasks, NumMeshes + 31);
	Packets.Reserve(InTaskData.TaskConfig.Relevance.NumEstimatedPackets);
	CreateRelevancePacket();
}

void FComputeAndMarkRelevance::AddPrimitives(FPrimitiveIndexList&& PrimitiveIndexList)
{
	if (PrimitiveIndexList.Num() == NumPrimitivesPerPacket)
	{
		// Create a one-off packet that will take all the primitives.
		FRelevancePacket* Packet = CreateRelevancePacket();
		Packet->Input.Prims = MoveTemp(PrimitiveIndexList);

		if (bLaunchOnAddPrimitive)
		{
			Packet->LaunchComputeRelevanceTask();
		}

		// Put the previous last packet that was in progress back in the last slot.
		Swap(Packets[Packets.Num() - 1], Packets[Packets.Num() - 2]);
	}

	else
	{
		for (int32 Index : PrimitiveIndexList)
		{
			AddPrimitive(Index);
		}
	}
}

void FComputeAndMarkRelevance::AddPrimitive(int32 Index)
{
	FRelevancePacket* Packet = Packets.Last();

	if (Packet->Input.AddPrim(Index); Packet->Input.IsFull())
	{
		if (bLaunchOnAddPrimitive)
		{
			Packet->LaunchComputeRelevanceTask();
		}
		CreateRelevancePacket();
	}
}

void FComputeAndMarkRelevance::Finish(UE::Tasks::FTaskEvent& ComputeRelevanceTaskEvent)
{
	check(!bFinished);
	bFinished = true;

	SCOPED_NAMED_EVENT(FinishRelevance, FColor::Magenta);

	Packets.Last()->LaunchComputeRelevanceTask();

	for (FRelevancePacket* Packet : Packets)
	{
		if (Packet->bComputeRelevanceTaskLaunched)
		{
			ComputeRelevanceTaskEvent.AddPrerequisites(Packet->ComputeRelevanceTask);
		}
	}

	ComputeRelevanceTaskEvent.Trigger();
}

void FComputeAndMarkRelevance::Finalize()
{
	check(bFinished && !bFinalized);
	bFinalized = true;
	PrerequisitesTask.Wait();

	if (!bLaunchOnAddPrimitive)
	{
		ParallelFor(Packets.Num(), [this](int32 Index)
		{
			FTaskTagScope Scope(ETaskTag::EParallelRenderingThread);
			FDynamicPrimitiveIndexList DynamicPrimitiveIndexList;

			FRelevancePacket* Packet = Packets[Index];
			Packet->ComputeRelevance(DynamicPrimitiveIndexList);
		});
	}

	SCOPED_NAMED_EVENT(FinalizeRelevance, FColor::Magenta);

	{
		QUICK_SCOPE_CYCLE_COUNTER(STAT_ComputeAndMarkRelevanceForViewParallel_Finalize);

		for (int32 PassIndex = 0; PassIndex < EMeshPass::Num; PassIndex++)
		{
			int32 NumVisibleCachedMeshDrawCommands = 0;
			int32 NumDynamicBuildRequests = 0;
			int32 NumDynamicBuildFlags = 0;

			for (auto Packet : Packets)
			{
				NumVisibleCachedMeshDrawCommands += Packet->DrawCommandPacket.VisibleCachedDrawCommands[PassIndex].Num();
				NumDynamicBuildRequests += Packet->DrawCommandPacket.DynamicBuildRequests[PassIndex].Num();
				NumDynamicBuildFlags += Packet->DrawCommandPacket.DynamicBuildFlags[PassIndex].Num();
			}

			ViewCommands.MeshCommands[PassIndex].Reserve(NumVisibleCachedMeshDrawCommands);
			ViewCommands.DynamicMeshCommandBuildRequests[PassIndex].Reserve(NumDynamicBuildRequests);
			ViewCommands.DynamicMeshCommandBuildFlags[PassIndex].Reserve(NumDynamicBuildFlags);
			check(NumDynamicBuildRequests == NumDynamicBuildFlags);
		}

		View.DirtyIndirectLightingCacheBufferPrimitivesMutex.Lock();

		for (auto Packet : Packets)
		{
			Packet->Finalize();
			delete Packet;
		}

		View.DirtyIndirectLightingCacheBufferPrimitivesMutex.Unlock();

		Packets.Empty();

		// Finalize Nanite materials
		if (TaskData.bAddNaniteRelevance)
		{
			// This needs to complete before InitViews runs so that combined primitive/material relevance has been computed for Nanite
			Scene.WaitForCacheNaniteMaterialBinsTask();

			FViewInfo& WriteView = View;
			{
				const FNaniteShadingPipelines& ShadingPipelines = Scene.NaniteShadingPipelines[ENaniteMeshPass::BasePass];
				const FPrimitiveViewRelevance& CombinedRelevance = ShadingPipelines.CombinedRelevance;

				WriteView.ShadingModelMaskInView |= CombinedRelevance.ShadingModelMask;
				WriteView.bUsesGlobalDistanceField |= CombinedRelevance.bUsesGlobalDistanceField;
				WriteView.bUsesLightingChannels |= CombinedRelevance.bUsesLightingChannels;
				WriteView.bSceneHasSkyMaterial |= CombinedRelevance.bUsesSkyMaterial;
				WriteView.bHasDistortionPrimitives |= CombinedRelevance.bDistortion;
				WriteView.bHasCustomDepthPrimitives |= CombinedRelevance.bRenderCustomDepth;
				WriteView.bUsesCustomDepth |= (CombinedRelevance.CustomDepthStencilUsageMask & 1) > 0;
				WriteView.bUsesCustomStencil |= (CombinedRelevance.CustomDepthStencilUsageMask & (1 << 1)) > 0;
				WriteView.SubstrateViewData.MaxClosurePerPixel = FMath::Max(WriteView.SubstrateViewData.MaxClosurePerPixel, 8u - FMath::CountLeadingZeros8(CombinedRelevance.SubstrateClosureCountMask));
				WriteView.SubstrateViewData.MaxBytesPerPixel = FMath::Max(WriteView.SubstrateViewData.MaxBytesPerPixel, CombinedRelevance.SubstrateUintPerPixel * 4u);
				WriteView.SubstrateViewData.bUsesComplexSpecialRenderPath |= CombinedRelevance.bUsesComplexSpecialRenderPath;
			}
		}
	}

	TRACE_COUNTER_SET(Scene_Visibility_Relevance_NumPrimitivesProcessed, TaskData.TaskConfig.Relevance.NumPrimitivesProcessed);

	QUICK_SCOPE_CYCLE_COUNTER(STAT_ComputeAndMarkRelevanceForViewParallel_TransposeMeshBits);
	check(View.StaticMeshVisibilityMap.Num() == NumMeshes &&
		View.StaticMeshFadeOutDitheredLODMap.Num() == NumMeshes &&
		View.StaticMeshFadeInDitheredLODMap.Num() == NumMeshes
	);
	uint32* RESTRICT StaticMeshVisibilityMap_Words = View.StaticMeshVisibilityMap.GetData();
	uint32* RESTRICT StaticMeshFadeOutDitheredLODMap_Words = View.StaticMeshFadeOutDitheredLODMap.GetData();
	uint32* RESTRICT StaticMeshFadeInDitheredLODMap_Words = View.StaticMeshFadeInDitheredLODMap.GetData();
	const uint64* RESTRICT MarkMasks64 = (const uint64 * RESTRICT)MarkMasks;
	const uint8* RESTRICT MarkMasks8 = MarkMasks;
	for (uint32 BaseIndex = 0; BaseIndex < NumMeshes; BaseIndex += 32)
	{
		uint32 StaticMeshVisibilityMap_Word = 0;
		uint32 StaticMeshFadeOutDitheredLODMap_Word = 0;
		uint32 StaticMeshFadeInDitheredLODMap_Word = 0;
		uint32 Mask = 1;
		bool bAny = false;
		for (int32 QWordIndex = 0; QWordIndex < 4; QWordIndex++)
		{
			if (*MarkMasks64++)
			{
				for (int32 ByteIndex = 0; ByteIndex < 8; ByteIndex++, Mask <<= 1, MarkMasks8++)
				{
					uint8 MaskMask = *MarkMasks8;
					StaticMeshVisibilityMap_Word |= (MaskMask & EMarkMaskBits::StaticMeshVisibilityMapMask) ? Mask : 0;
					StaticMeshFadeOutDitheredLODMap_Word |= (MaskMask & EMarkMaskBits::StaticMeshFadeOutDitheredLODMapMask) ? Mask : 0;
					StaticMeshFadeInDitheredLODMap_Word |= (MaskMask & EMarkMaskBits::StaticMeshFadeInDitheredLODMapMask) ? Mask : 0;
				}
				bAny = true;
			}
			else
			{
				MarkMasks8 += 8;
				Mask <<= 8;
			}
		}
		if (bAny)
		{
			checkSlow(!*StaticMeshVisibilityMap_Words && !*StaticMeshFadeOutDitheredLODMap_Words && !*StaticMeshFadeInDitheredLODMap_Words);
			*StaticMeshVisibilityMap_Words = StaticMeshVisibilityMap_Word;
			*StaticMeshFadeOutDitheredLODMap_Words = StaticMeshFadeOutDitheredLODMap_Word;
			*StaticMeshFadeInDitheredLODMap_Words = StaticMeshFadeInDitheredLODMap_Word;
		}
		StaticMeshVisibilityMap_Words++;
		StaticMeshFadeOutDitheredLODMap_Words++;
		StaticMeshFadeInDitheredLODMap_Words++;
	}

	if (View.bIsSinglePassStereo)
	{
		check(View.StereoPass != EStereoscopicPass::eSSP_SECONDARY); // Secondary views should not calculate relevance
		if (const FViewInfo* SecondaryViewConst = View.GetInstancedView())
		{
			FViewInfo* SecondaryView = const_cast<FViewInfo*>(SecondaryViewConst);
			SecondaryView->PrimitiveVisibilityMap = View.PrimitiveVisibilityMap;
			SecondaryView->PrimitiveRayTracingVisibilityMap = View.PrimitiveRayTracingVisibilityMap;
			SecondaryView->PrimitiveDefinitelyUnoccludedMap = View.PrimitiveDefinitelyUnoccludedMap;
			SecondaryView->PrimitiveViewRelevanceMap = View.PrimitiveViewRelevanceMap;
			SecondaryView->StaticMeshVisibilityMap = View.StaticMeshVisibilityMap;
			SecondaryView->PrimitivesLODMask = View.PrimitivesLODMask;
			SecondaryView->NumVisibleDynamicPrimitives = View.NumVisibleDynamicPrimitives;
			SecondaryView->NumVisibleDynamicEditorPrimitives = View.NumVisibleDynamicEditorPrimitives;

			SecondaryView->ShadingModelMaskInView = View.ShadingModelMaskInView;
			SecondaryView->bUsesGlobalDistanceField = View.bUsesGlobalDistanceField;
			SecondaryView->bUsesLightingChannels = View.bUsesLightingChannels;
			SecondaryView->bTranslucentSurfaceLighting = View.bTranslucentSurfaceLighting;
			SecondaryView->bSceneHasSkyMaterial = View.bSceneHasSkyMaterial;
			SecondaryView->bHasSingleLayerWaterMaterial = View.bHasSingleLayerWaterMaterial;
			SecondaryView->bUsesSecondStageDepthPass = View.bUsesSecondStageDepthPass;
			SecondaryView->TranslucentPrimCount = View.TranslucentPrimCount;
			SecondaryView->bHasDistortionPrimitives = View.bHasDistortionPrimitives;
			SecondaryView->bHasCustomDepthPrimitives = View.bHasCustomDepthPrimitives;
			SecondaryView->CustomDepthStencilValues = View.CustomDepthStencilValues;
			SecondaryView->bUsesCustomDepth = View.bUsesCustomDepth;
			SecondaryView->bUsesCustomStencil = View.bUsesCustomStencil;
			SecondaryView->SubstrateViewData.MaxClosurePerPixel = View.SubstrateViewData.MaxClosurePerPixel;
			SecondaryView->SubstrateViewData.MaxBytesPerPixel = View.SubstrateViewData.MaxClosurePerPixel;
			SecondaryView->SubstrateViewData.bUsesComplexSpecialRenderPath = View.SubstrateViewData.bUsesComplexSpecialRenderPath;
		}
	}
}

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

static void ComputeDynamicMeshRelevance(
	EShadingPath ShadingPath,
	bool bAddLightmapDensityCommands,
	bool bIsTLVUsingVoxelMarking,
	const FPrimitiveViewRelevance& ViewRelevance,
	const FMeshBatchAndRelevance& MeshBatch,
	FViewInfo& View,
	FMeshPassMask& PassMask,
	FPrimitiveSceneInfo* PrimitiveSceneInfo,
	const FPrimitiveBounds& Bounds)
{
	const int32 NumElements = MeshBatch.Mesh->Elements.Num();

	if (ViewRelevance.bDrawRelevance && (ViewRelevance.bRenderInMainPass || ViewRelevance.bRenderCustomDepth || ViewRelevance.bRenderInDepthPass))
	{
		if (ViewRelevance.bRenderInSecondStageDepthPass && ShadingPath != EShadingPath::Mobile)
		{
			PassMask.Set(EMeshPass::SecondStageDepthPass);
			View.NumVisibleDynamicMeshElements[EMeshPass::SecondStageDepthPass] += NumElements;
		}
		else
		{
			PassMask.Set(EMeshPass::DepthPass);
			View.NumVisibleDynamicMeshElements[EMeshPass::DepthPass] += NumElements;
		}

		if (ViewRelevance.bRenderInMainPass || ViewRelevance.bRenderCustomDepth)
		{
			PassMask.Set(EMeshPass::BasePass);
			View.NumVisibleDynamicMeshElements[EMeshPass::BasePass] += NumElements;

			if (ViewRelevance.bUsesSkyMaterial)
			{
				PassMask.Set(EMeshPass::SkyPass);
				View.NumVisibleDynamicMeshElements[EMeshPass::SkyPass] += NumElements;
			}

			if (ViewRelevance.bUsesAnisotropy)
			{
				PassMask.Set(EMeshPass::AnisotropyPass);
				View.NumVisibleDynamicMeshElements[EMeshPass::AnisotropyPass] += NumElements;
			}

			if (ShadingPath == EShadingPath::Mobile)
			{
				PassMask.Set(EMeshPass::MobileBasePassCSM);
				View.NumVisibleDynamicMeshElements[EMeshPass::MobileBasePassCSM] += NumElements;
			}

			if (ViewRelevance.bRenderCustomDepth)
			{
				PassMask.Set(EMeshPass::CustomDepth);
				View.NumVisibleDynamicMeshElements[EMeshPass::CustomDepth] += NumElements;
			}

			if (bAddLightmapDensityCommands)
			{
				PassMask.Set(EMeshPass::LightmapDensity);
				View.NumVisibleDynamicMeshElements[EMeshPass::LightmapDensity] += NumElements;
			}
#if !(UE_BUILD_SHIPPING || UE_BUILD_TEST)
			else if (View.Family->UseDebugViewPS())
			{
				PassMask.Set(EMeshPass::DebugViewMode);
				View.NumVisibleDynamicMeshElements[EMeshPass::DebugViewMode] += NumElements;
			}
#endif

#if WITH_EDITOR
			if (View.bAllowTranslucentPrimitivesInHitProxy)
			{
				PassMask.Set(EMeshPass::HitProxy);
				View.NumVisibleDynamicMeshElements[EMeshPass::HitProxy] += NumElements;
			}
			else
			{
				PassMask.Set(EMeshPass::HitProxyOpaqueOnly);
				View.NumVisibleDynamicMeshElements[EMeshPass::HitProxyOpaqueOnly] += NumElements;
			}
#endif

			if (ViewRelevance.bVelocityRelevance)
			{
				PassMask.Set(EMeshPass::Velocity);
				View.NumVisibleDynamicMeshElements[EMeshPass::Velocity] += NumElements;
			}

			if (ViewRelevance.bOutputsTranslucentVelocity)
			{
				PassMask.Set(EMeshPass::TranslucentVelocity);
				View.NumVisibleDynamicMeshElements[EMeshPass::TranslucentVelocity] += NumElements;
			}

			if (ViewRelevance.bUsesSingleLayerWaterMaterial)
			{
				PassMask.Set(EMeshPass::SingleLayerWaterPass);
				View.NumVisibleDynamicMeshElements[EMeshPass::SingleLayerWaterPass] += NumElements;
				PassMask.Set(EMeshPass::SingleLayerWaterDepthPrepass);
				View.NumVisibleDynamicMeshElements[EMeshPass::SingleLayerWaterDepthPrepass] += NumElements;
			}
		}
	}

	if (ViewRelevance.HasTranslucency()
		&& !ViewRelevance.bEditorPrimitiveRelevance
		&& ViewRelevance.bRenderInMainPass)
	{
		if (View.Family->AllowTranslucencyAfterDOF())
		{
			if ((ViewRelevance.bNormalTranslucency || (View.AutoBeforeDOFTranslucencyBoundary > 0.0f && ViewRelevance.bSeparateTranslucency)))
			{
				PassMask.Set(EMeshPass::TranslucencyStandard);
				View.NumVisibleDynamicMeshElements[EMeshPass::TranslucencyStandard] += NumElements;
			}

			if ((ViewRelevance.bNormalTranslucency || (View.AutoBeforeDOFTranslucencyBoundary > 0.0f && ViewRelevance.bSeparateTranslucency)) && ViewRelevance.bTranslucencyModulate && View.Family->AllowStandardTranslucencySeparated())
			{
				PassMask.Set(EMeshPass::TranslucencyStandardModulate);
				View.NumVisibleDynamicMeshElements[EMeshPass::TranslucencyStandardModulate] += NumElements;
			}

			if (ViewRelevance.bSeparateTranslucency)
			{
				PassMask.Set(EMeshPass::TranslucencyAfterDOF);
				View.NumVisibleDynamicMeshElements[EMeshPass::TranslucencyAfterDOF] += NumElements;
			}

			if (ViewRelevance.bSeparateTranslucency && ViewRelevance.bTranslucencyModulate)
			{
				PassMask.Set(EMeshPass::TranslucencyAfterDOFModulate);
				View.NumVisibleDynamicMeshElements[EMeshPass::TranslucencyAfterDOFModulate] += NumElements;
			}

			if (ViewRelevance.bPostMotionBlurTranslucency)
			{
				PassMask.Set(EMeshPass::TranslucencyAfterMotionBlur);
				View.NumVisibleDynamicMeshElements[EMeshPass::TranslucencyAfterMotionBlur] += NumElements;
			}
		}
		else
		{
			PassMask.Set(EMeshPass::TranslucencyAll);
			View.NumVisibleDynamicMeshElements[EMeshPass::TranslucencyAll] += NumElements;
		}

		{
			PassMask.Set(EMeshPass::TranslucencyHoldout);
			View.NumVisibleDynamicMeshElements[EMeshPass::TranslucencyHoldout] += NumElements;
		}

		if (ViewRelevance.bTranslucentSurfaceLighting || bIsTLVUsingVoxelMarking)
		{
			PassMask.Set(EMeshPass::LumenTranslucencyRadianceCacheMark);
			View.NumVisibleDynamicMeshElements[EMeshPass::LumenTranslucencyRadianceCacheMark] += NumElements;
		}

		if (ViewRelevance.bTranslucentSurfaceLighting)
		{
			PassMask.Set(EMeshPass::LumenFrontLayerTranslucencyGBuffer);
			View.NumVisibleDynamicMeshElements[EMeshPass::LumenFrontLayerTranslucencyGBuffer] += NumElements;
		}

		if (ViewRelevance.bDistortion)
		{
			PassMask.Set(EMeshPass::Distortion);
			View.NumVisibleDynamicMeshElements[EMeshPass::Distortion] += NumElements;
		}
	}

#if WITH_EDITOR
	if (ViewRelevance.bDrawRelevance)
	{
		PassMask.Set(EMeshPass::EditorSelection);
		View.NumVisibleDynamicMeshElements[EMeshPass::EditorSelection] += NumElements;

		PassMask.Set(EMeshPass::EditorLevelInstance);
		View.NumVisibleDynamicMeshElements[EMeshPass::EditorLevelInstance] += NumElements;
	}

	// Hair strands are not rendered into the base pass (bRenderInMainPass=0) and so this 
	// adds a special pass for allowing hair strands to be selectable.
	if (ViewRelevance.bHairStrands)
	{
		const EMeshPass::Type MeshPassType = View.bAllowTranslucentPrimitivesInHitProxy ? EMeshPass::HitProxy : EMeshPass::HitProxyOpaqueOnly;
		PassMask.Set(MeshPassType);
		View.NumVisibleDynamicMeshElements[MeshPassType] += NumElements;
	}
#endif

	if (ViewRelevance.bHasVolumeMaterialDomain)
	{
		if (ShouldRenderMeshBatchWithHeterogeneousVolumes(MeshBatch.Mesh, MeshBatch.PrimitiveSceneProxy, View.FeatureLevel))
		{
			View.HeterogeneousVolumesMeshBatches.AddUninitialized(1);
			FVolumetricMeshBatch& BatchAndProxy = View.HeterogeneousVolumesMeshBatches.Last();
			BatchAndProxy.Mesh = MeshBatch.Mesh;
			BatchAndProxy.Proxy = MeshBatch.PrimitiveSceneProxy;
		}
		else
		{
			View.VolumetricMeshBatches.AddUninitialized(1);
			FVolumetricMeshBatch& BatchAndProxy = View.VolumetricMeshBatches.Last();
			BatchAndProxy.Mesh = MeshBatch.Mesh;
			BatchAndProxy.Proxy = MeshBatch.PrimitiveSceneProxy;
		}
	}

	if (ViewRelevance.bUsesSkyMaterial)
	{
		View.SkyMeshBatches.AddUninitialized(1);
		FSkyMeshBatch& BatchAndProxy = View.SkyMeshBatches.Last();
		BatchAndProxy.Mesh = MeshBatch.Mesh;
		BatchAndProxy.Proxy = MeshBatch.PrimitiveSceneProxy;
		BatchAndProxy.bVisibleInMainPass = ViewRelevance.bRenderInMainPass;
		BatchAndProxy.bVisibleInRealTimeSkyCapture = PrimitiveSceneInfo->bVisibleInRealTimeSkyCapture;
	}

	if (ViewRelevance.HasTranslucency() && PrimitiveSceneInfo->Proxy->SupportsSortedTriangles())
	{
		View.SortedTrianglesMeshBatches.AddUninitialized(1);
		FSortedTrianglesMeshBatch& BatchAndProxy = View.SortedTrianglesMeshBatches.Last();
		BatchAndProxy.Mesh = MeshBatch.Mesh;
		BatchAndProxy.Proxy = MeshBatch.PrimitiveSceneProxy;
	}

	if (ViewRelevance.bRenderInMainPass && ViewRelevance.bDecal)
	{
		// DecalRenderTargetModeMask could be cached in FMeshBatchAndRelevance as well
		const FMaterial& Material = MeshBatch.Mesh->MaterialRenderProxy->GetIncompleteMaterialWithFallback(View.FeatureLevel);
		uint8 DecalRenderTargetModeMask = DecalRendering::GetDecalRenderTargetModeMask(Material, View.FeatureLevel);
		for (uint8 DecalRenderTargetMode = 0; DecalRenderTargetMode < (uint8)EDecalRenderTargetMode::Num; ++DecalRenderTargetMode)
		{
			if (DecalRendering::IsCompatibleWithRenderTargetMode(DecalRenderTargetModeMask, (EDecalRenderTargetMode)DecalRenderTargetMode))
			{
				EMeshPass::Type DecalMeshPassType = DecalRendering::GetMeshPassType((EDecalRenderTargetMode)DecalRenderTargetMode);
				PassMask.Set(DecalMeshPassType);
				View.NumVisibleDynamicMeshElements[DecalMeshPassType] += NumElements;
			}
		}
	}

	const bool bIsHairStrandsCompatible = ViewRelevance.bHairStrands && IsHairStrandsEnabled(EHairStrandsShaderType::All, View.GetShaderPlatform());
	if (bIsHairStrandsCompatible)
	{
		// Disable bCheckLengthScaleInitialize when running hit proxy as LengthScale is not initialized
		const bool bCheckLengthScale = !View.Family->EngineShowFlags.HitProxies;
		if (HairStrands::IsHairStrandsVF(MeshBatch.Mesh) && HairStrands::IsHairVisible(MeshBatch, bCheckLengthScale))
		{
			View.HairStrandsMeshElements.AddUninitialized(1);
			FMeshBatchAndRelevance& BatchAndProxy = View.HairStrandsMeshElements.Last();
			BatchAndProxy = MeshBatch;
		}

		if (HairStrands::IsHairCardsVF(MeshBatch.Mesh) && ViewRelevance.bRenderInMainPass)
		{
			View.HairCardsMeshElements.AddUninitialized(1);
			FMeshBatchAndRelevance& BatchAndProxy = View.HairCardsMeshElements.Last();
			BatchAndProxy = MeshBatch;
		}
	}
}

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

FGPUOcclusionPacket::FGPUOcclusionPacket(FVisibilityViewPacket& InViewPacket, const FGPUOcclusionState& InOcclusionState)
	: ViewPacket(InViewPacket)
	, View(ViewPacket.View)
	, ViewState(*ViewPacket.ViewState)
	, ViewElementPDI(ViewPacket.ViewElementPDI)
	, HZBOcclusionTests(ViewState.HZBOcclusionTests)
	, OcclusionFeedback(ViewState.OcclusionFeedback)
	, PrimitiveOcclusionHistorySet(ViewState.Occlusion.PrimitiveOcclusionHistorySet)
	, Scene(ViewPacket.Scene)
	, OcclusionState(InOcclusionState)
	, ViewOrigin(View.ViewMatrices.GetViewOrigin())
	, OcclusionFrameCounter(ViewState.OcclusionFrameCounter)
	, PrimitiveProbablyVisibleTime(GEngine->PrimitiveProbablyVisibleTime)
	, CurrentRealTime(View.Family->Time.GetRealTimeSeconds())
	, NeverOcclusionTestDistanceSquared(GNeverOcclusionTestDistance* GNeverOcclusionTestDistance)
	, bUseOcclusionFeedback(OcclusionFeedback.IsInitialized())
	, bNewlyConsideredBBoxExpandActive(GExpandNewlyOcclusionTestedBBoxesAmount > 0.0f && GFramesToExpandNewlyOcclusionTestedBBoxes > 0 && GFramesNotOcclusionTestedToExpandBBoxes > 0)
{}

template <bool bIsParallel, typename VisitorType>
bool FGPUOcclusionPacket::OcclusionCullPrimitive(VisitorType& Visitor, FOcclusionCullResult& Result, int32 Index)
{
	const uint8 OcclusionFlags = Scene.PrimitiveOcclusionFlags[Index];

	int32 NumSubQueries = 1;
	bool bSubQueries = false;
	const TArray<FBoxSphereBounds>* SubBounds = nullptr;
	int32 SubIsOccludedStart = 0;

	const auto SetAtomicBit = [] (FSceneBitArray& Array, int32 Index, bool Value)
	{
		if constexpr (bIsParallel)
		{
			Array[Index].AtomicSet(Value);
		}
		else
		{
			Array[Index] = Value;
		}
	};

	if (OcclusionFlags & EOcclusionFlags::IsForceHidden)
	{
		// Primitive is not visible and does not need to be occlusion tested
		return false;
	}

	if ((OcclusionFlags & EOcclusionFlags::HasSubprimitiveQueries) && OcclusionState.bAllowSubQueries)
	{
		FPrimitiveSceneProxy* Proxy = Scene.PrimitiveSceneProxies[Index];
		SubBounds = Proxy->GetOcclusionQueries(&View);
		NumSubQueries = SubBounds->Num();
		bSubQueries = true;
		if (!NumSubQueries)
		{
			SetAtomicBit(View.PrimitiveVisibilityMap, Index, false);
			return false;
		}

		if (!SubIsOccluded || SubIsOccluded->Num() + NumSubQueries > SubIsOccluded->Max())
		{
			SubIsOccluded = View.Allocator.Create<TArray<bool>>();
			SubIsOccluded->Reserve(FMath::Max<uint32>(NumSubQueries, SubIsOccludedPageSize));
		}

		SubIsOccludedStart = SubIsOccluded->Num();
	}

	bool bIsVisible = true;
	bool bAllSubOcclusionStateIsDefinite = true;
	bool bAllSubOccluded = true;
	FPrimitiveComponentId PrimitiveId = Scene.PrimitiveComponentIds[Index];

	for (int32 SubQuery = 0; SubQuery < NumSubQueries; SubQuery++)
	{
		FPrimitiveOcclusionHistory* PrimitiveOcclusionHistory = PrimitiveOcclusionHistorySet.Find(FPrimitiveOcclusionHistoryKey(PrimitiveId, SubQuery));

		bool bIsOccluded = false;
		bool bOcclusionStateIsDefinite = false;

		if (!PrimitiveOcclusionHistory)
		{
			PrimitiveOcclusionHistory = Visitor.AddOcclusionHistory(FPrimitiveOcclusionHistory(PrimitiveId, SubQuery));
		}
		else
		{
			if (View.bIgnoreExistingQueries)
			{
				// If the view is ignoring occlusion queries, the primitive is definitely unoccluded.
				bOcclusionStateIsDefinite = View.bDisableQuerySubmissions;
			}
			else
			{
				if (bUseOcclusionFeedback)
				{
					bIsOccluded = OcclusionFeedback.IsOccluded(FPrimitiveOcclusionHistoryKey(PrimitiveId, SubQuery));
					bOcclusionStateIsDefinite = true;
				}
				else if (OcclusionState.bHZBOcclusion)
				{
					if (HZBOcclusionTests.IsValidFrame(PrimitiveOcclusionHistory->LastTestFrameNumber))
					{
						bIsOccluded = !HZBOcclusionTests.IsVisible(PrimitiveOcclusionHistory->HZBTestIndex);
						bOcclusionStateIsDefinite = true;
					}
				}
				else
				{
					// Read the occlusion query results.
					uint64 NumSamples = 0;
					bool bGrouped = false;
					FRHIRenderQuery* PastQuery = PrimitiveOcclusionHistory->GetQueryForReading(OcclusionFrameCounter, OcclusionState.NumBufferedFrames, OcclusionState.ReadBackLagTolerance, bGrouped);
					if (PastQuery)
					{
						if (RHIGetRenderQueryResult(PastQuery, NumSamples, true))
						{
							// we render occlusion without MSAA
							uint32 NumPixels = (uint32)NumSamples;

							// The primitive is occluded if none of its bounding box's pixels were visible in the previous frame's occlusion query.
							bIsOccluded = (NumPixels == 0);

							if (!bIsOccluded)
							{
								checkSlow(View.OneOverNumPossiblePixels > 0.0f);
								PrimitiveOcclusionHistory->LastPixelsPercentage = NumPixels * View.OneOverNumPossiblePixels;
							}
							else
							{
								PrimitiveOcclusionHistory->LastPixelsPercentage = 0.0f;
							}

							// Flag the primitive's occlusion state as definite if it wasn't grouped.
							bOcclusionStateIsDefinite = !bGrouped;
						}
						else
						{
							// If the occlusion query failed, treat the primitive as visible.  
							// already set bIsOccluded = false;
						}

						Result.NumTestedQueries++;
					}
					else
					{
						if (OcclusionState.NumBufferedFrames > 1 || GRHIMaximumInFlightQueries < MAX_int32)
						{
							// If there's no occlusion query for the primitive, assume it is whatever it was last frame
							bIsOccluded = PrimitiveOcclusionHistory->WasOccludedLastFrame;
							bOcclusionStateIsDefinite = PrimitiveOcclusionHistory->OcclusionStateWasDefiniteLastFrame;
						}
						else
						{
							// If there's no occlusion query for the primitive, set it's visibility state to whether it has been unoccluded recently.
							bIsOccluded = (PrimitiveOcclusionHistory->LastProvenVisibleTime + GEngine->PrimitiveProbablyVisibleTime < CurrentRealTime);
							// the state was definite last frame, otherwise we would have ran a query
							bOcclusionStateIsDefinite = true;
						}
						if (bIsOccluded)
						{
							PrimitiveOcclusionHistory->LastPixelsPercentage = 0.0f;
						}
						else
						{
							PrimitiveOcclusionHistory->LastPixelsPercentage = GEngine->MaxOcclusionPixelsFraction;
						}
					}
				}

				if (GVisualizeOccludedPrimitives && bIsOccluded)
				{
					const FBoxSphereBounds& Bounds = bSubQueries ? (*SubBounds)[SubQuery] : Scene.PrimitiveOcclusionBounds[Index];
					Visitor.AddVisualizeQuery(Bounds.GetBox());
				}
			}
		}

		if (OcclusionState.bSubmitQueries)
		{
			bool bSkipNewlyConsidered = false;

			if (bNewlyConsideredBBoxExpandActive)
			{
				if (!PrimitiveOcclusionHistory->BecameEligibleForQueryCooldown && OcclusionFrameCounter - PrimitiveOcclusionHistory->LastConsideredFrameNumber > uint32(GFramesNotOcclusionTestedToExpandBBoxes))
				{
					PrimitiveOcclusionHistory->BecameEligibleForQueryCooldown = GFramesToExpandNewlyOcclusionTestedBBoxes;
				}

				bSkipNewlyConsidered = !!PrimitiveOcclusionHistory->BecameEligibleForQueryCooldown;

				if (bSkipNewlyConsidered)
				{
					PrimitiveOcclusionHistory->BecameEligibleForQueryCooldown--;
				}
			}

			bool bAllowBoundsTest;
			const FBoxSphereBounds OcclusionBounds = (bSubQueries ? (*SubBounds)[SubQuery] : Scene.PrimitiveOcclusionBounds[Index]).ExpandBy(GExpandAllTestedBBoxesAmount + (bSkipNewlyConsidered ? GExpandNewlyOcclusionTestedBBoxesAmount : 0.0));
			if (FVector::DistSquared(ViewOrigin, OcclusionBounds.Origin) < NeverOcclusionTestDistanceSquared)
			{
				bAllowBoundsTest = false;
			}
			else if (View.bHasNearClippingPlane)
			{
				bAllowBoundsTest = View.NearClippingPlane.PlaneDot(OcclusionBounds.Origin) <
					-(FVector::BoxPushOut(View.NearClippingPlane, OcclusionBounds.BoxExtent));

			}
			else if (!View.IsPerspectiveProjection())
			{
				// Transform parallel near plane
				static_assert((int32)ERHIZBuffer::IsInverted != 0, "Check equation for culling!");
				bAllowBoundsTest = View.WorldToScreen(OcclusionBounds.Origin).Z - View.ViewMatrices.GetProjectionMatrix().M[2][2] * OcclusionBounds.SphereRadius < 1;
			}
			else
			{
				bAllowBoundsTest = OcclusionBounds.SphereRadius < HALF_WORLD_MAX;
			}

			if (bAllowBoundsTest)
			{
				PrimitiveOcclusionHistory->LastTestFrameNumber = OcclusionFrameCounter;

				if (bUseOcclusionFeedback)
				{
					const FVector BoundOrigin = OcclusionBounds.Origin + View.ViewMatrices.GetPreViewTranslation();
					const FVector BoundExtent = OcclusionBounds.BoxExtent;

					Visitor.AddOcclusionFeedback(FOcclusionFeedbackEntry(FPrimitiveOcclusionHistoryKey(PrimitiveId, SubQuery), BoundOrigin, BoundExtent));
				}
				else if (OcclusionState.bHZBOcclusion)
				{
					Visitor.AddHZBBounds(FHZBBound(PrimitiveOcclusionHistory, OcclusionBounds.Origin, OcclusionBounds.BoxExtent));
				}
				else
				{
					// decide if a query should be run this frame
					bool bRunQuery, bGroupedQuery;

					if (!bSubQueries && // sub queries are never grouped, we assume the custom code knows what it is doing and will group internally if it wants
						(OcclusionFlags & EOcclusionFlags::AllowApproximateOcclusion))
					{
						if (bIsOccluded)
						{
							// Primitives that were occluded the previous frame use grouped queries.
							bGroupedQuery = true;
							bRunQuery = true;
						}
						else if (bOcclusionStateIsDefinite)
						{
							bGroupedQuery = false;
							float Rnd = GOcclusionRandomStream.GetFraction();
							if (GRHISupportsExactOcclusionQueries)
							{
								float FractionMultiplier = FMath::Max(PrimitiveOcclusionHistory->LastPixelsPercentage / GEngine->MaxOcclusionPixelsFraction, 1.0f);
								bRunQuery = (FractionMultiplier * Rnd) < GEngine->MaxOcclusionPixelsFraction;
							}
							else
							{
								bRunQuery = CurrentRealTime - PrimitiveOcclusionHistory->LastProvenVisibleTime > PrimitiveProbablyVisibleTime * (0.5f * 0.25f * Rnd);
							}
						}
						else
						{
							bGroupedQuery = false;
							bRunQuery = true;
						}
					}
					else
					{
						// Primitives that need precise occlusion results use individual queries.
						bGroupedQuery = false;
						bRunQuery = true;
					}

					if (bRunQuery)
					{
						const FVector BoundOrigin = OcclusionBounds.Origin + View.ViewMatrices.GetPreViewTranslation();
						const FVector BoundExtent = OcclusionBounds.BoxExtent;

						if (GRHIMaximumInFlightQueries < MAX_int32 && !bGroupedQuery)
						{
							Visitor.AddThrottledOcclusionQuery(FThrottledOcclusionQuery(FPrimitiveOcclusionHistoryKey(PrimitiveId, SubQuery), BoundOrigin, BoundExtent, PrimitiveOcclusionHistory->LastQuerySubmitFrame()));
						}
						else
						{
							Visitor.AddOcclusionQuery(FOcclusionQuery(PrimitiveOcclusionHistory, BoundOrigin, BoundExtent, bGroupedQuery));
						}
					}
				}
			}
			else
			{
				// If the primitive's bounding box intersects the near clipping plane, treat it as definitely unoccluded.
				bIsOccluded = false;
				bOcclusionStateIsDefinite = true;
			}
		}

		// Set the primitive's considered time to keep its occlusion history from being trimmed.
		PrimitiveOcclusionHistory->LastConsideredTime = CurrentRealTime;
		if (!bIsOccluded && bOcclusionStateIsDefinite)
		{
			PrimitiveOcclusionHistory->LastProvenVisibleTime = CurrentRealTime;
		}

		PrimitiveOcclusionHistory->LastConsideredFrameNumber = OcclusionFrameCounter;
		PrimitiveOcclusionHistory->WasOccludedLastFrame = bIsOccluded;
		PrimitiveOcclusionHistory->OcclusionStateWasDefiniteLastFrame = bOcclusionStateIsDefinite;

		if (bSubQueries)
		{
			SubIsOccluded->Add(bIsOccluded);
			if (!bIsOccluded)
			{
				bAllSubOccluded = false;
			}
			if (bIsOccluded || !bOcclusionStateIsDefinite)
			{
				bAllSubOcclusionStateIsDefinite = false;
			}
		}
		else
		{
			if (bIsOccluded)
			{
				SetAtomicBit(View.PrimitiveVisibilityMap, Index, false);
				bIsVisible = false;
				Result.NumCulledPrimitives++;
			}
			else if (bOcclusionStateIsDefinite)
			{
				SetAtomicBit(View.PrimitiveDefinitelyUnoccludedMap, Index, true);
			}
		}
	}

	if (bSubQueries)
	{
		FPrimitiveSceneProxy* Proxy = Scene.PrimitiveSceneProxies[Index];
		Proxy->AcceptOcclusionResults(&View, SubIsOccluded, SubIsOccludedStart, SubIsOccluded->Num() - SubIsOccludedStart);

		if (bAllSubOccluded)
		{
			SetAtomicBit(View.PrimitiveVisibilityMap, Index, false);
			bIsVisible = false;
			Result.NumCulledPrimitives++;
		}
		else if (bAllSubOcclusionStateIsDefinite)
		{
			SetAtomicBit(View.PrimitiveDefinitelyUnoccludedMap, Index, true);
		}
	}

	return bIsVisible;
}

void FGPUOcclusionPacket::FProcessVisitor::AddOcclusionQuery(const FOcclusionQuery& Query)
{
	FRHIRenderQuery* RenderQuery = nullptr;

	if (Query.bGroupedQuery)
	{
		RenderQuery = Packet.View.GroupedOcclusionQueries.BatchPrimitive(Query.Bounds.Origin, Query.Bounds.Extent, DynamicVertexBuffer);
	}
	else
	{
		RenderQuery = Packet.View.IndividualOcclusionQueries.BatchPrimitive(Query.Bounds.Origin, Query.Bounds.Extent, DynamicVertexBuffer);
	}

	const uint32 QueryIndex = FOcclusionQueryHelpers::GetQueryIssueIndex(Packet.ViewState.OcclusionFrameCounter, Packet.OcclusionState.NumBufferedFrames);
	Packet.ViewState.Occlusion.LastOcclusionQueryArray[QueryIndex] = RenderQuery;
	Packet.ViewState.Occlusion.NumRequestedQueries++;

	Query.PrimitiveOcclusionHistory->SetCurrentQuery(
		Packet.ViewState.OcclusionFrameCounter,
		RenderQuery,
		Packet.OcclusionState.NumBufferedFrames,
		Query.bGroupedQuery,
		Packet.OcclusionState.bUseRoundRobinOcclusion
	);
}

void FGPUOcclusionPacket::FProcessVisitor::SubmitThrottledOcclusionQueries()
{
	if (ThrottledOcclusionQueries.IsEmpty())
	{
		return;
	}

	TArray<FThrottledOcclusionQuery*, SceneRenderingAllocator> SortedQueries;
	SortedQueries.Reserve(ThrottledOcclusionQueries.Num());

	for (FThrottledOcclusionQuery& ThrottledOcclusionQuery : ThrottledOcclusionQueries)
	{
		SortedQueries.Emplace(&ThrottledOcclusionQuery);
	}

	const int32 NumRequestedThrottledQueries = SortedQueries.Num();
	const int32 NumUsedQueries = Packet.View.GroupedOcclusionQueries.GetNumBatchOcclusionQueries();
	const int32 ThrottleThreshold = GRHIMaximumInFlightQueries / FMath::Min(Packet.OcclusionState.NumBufferedFrames, 2); // extra RHIT frame does not count

	int32 NumThrottledQueries = NumRequestedThrottledQueries;

	if (NumUsedQueries + NumRequestedThrottledQueries > ThrottleThreshold)
	{
		// We need to make progress, even if it means stalling and waiting for the GPU. At a minimum, we will do 10%.
		NumThrottledQueries = (NumRequestedThrottledQueries + 9) / 10;

		if (NumUsedQueries + NumThrottledQueries < ThrottleThreshold)
		{
			// We can do more than the minimum.
			NumThrottledQueries = ThrottleThreshold - NumUsedQueries;
		}
	}

	if (NumThrottledQueries < NumRequestedThrottledQueries)
	{
		SortedQueries.Sort([](const FThrottledOcclusionQuery& A, const FThrottledOcclusionQuery& B)
		{
			return A.LastQuerySubmitFrame < B.LastQuerySubmitFrame;
		});
	}

	for (int32 Index = 0; Index < NumThrottledQueries; ++Index)
	{
		FThrottledOcclusionQuery* Query = SortedQueries[Index];
		FPrimitiveOcclusionHistory* PrimitiveOcclusionHistory = PrimitiveOcclusionHistorySet.Find(Query->PrimitiveOcclusionHistoryKey);

		FRHIRenderQuery* RenderQuery = Packet.View.IndividualOcclusionQueries.BatchPrimitive(Query->Bounds.Origin, Query->Bounds.Extent, DynamicVertexBuffer);

		const uint32 QueryIndex = FOcclusionQueryHelpers::GetQueryIssueIndex(Packet.ViewState.OcclusionFrameCounter, Packet.OcclusionState.NumBufferedFrames);
		Packet.ViewState.Occlusion.LastOcclusionQueryArray[QueryIndex] = RenderQuery;
		Packet.ViewState.Occlusion.NumRequestedQueries++;

		PrimitiveOcclusionHistory->SetCurrentQuery(
			Packet.ViewState.OcclusionFrameCounter,
			RenderQuery,
			Packet.OcclusionState.NumBufferedFrames,
			false,
			Packet.OcclusionState.bUseRoundRobinOcclusion
		);
	}
}

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

FGPUOcclusion::FGPUOcclusion(FVisibilityViewPacket& InViewPacket)
	: ViewPacket(InViewPacket)
	, Scene(ViewPacket.Scene)
	, View(ViewPacket.View)
	, ViewState(*ViewPacket.ViewState)
{
	// In single pass stereo we only submit queries from the primary view.
	State.bSubmitQueries = !View.bDisableQuerySubmissions && !(View.bIsSinglePassStereo && View.StereoPass == EStereoscopicPass::eSSP_SECONDARY);

#if !(UE_BUILD_SHIPPING || UE_BUILD_TEST)
	State.bSubmitQueries &= !ViewState.bIsFrozen;
#endif

	// Perform round-robin occlusion queries
	const bool bUseRoundRobinOcclusion = ViewState.IsRoundRobinEnabled() &&
		!View.bIsSinglePassStereo && // No round robin on single-pass stereo
		!View.bIsSceneCapture && // We only round-robin on the main renderer (not scene captures)
		IStereoRendering::IsStereoEyeView(View); // Only relevant to stereo views
	if (bUseRoundRobinOcclusion && !View.bIgnoreExistingQueries) // We do not alternate occlusion queries when we want to refresh the occlusion history
	{
		// For even frames, prevent left eye from occlusion querying
		// For odd frames, prevent right eye from occlusion querying
		const bool FrameParity = ((ViewState.PrevFrameNumber & 0x01) == 1);
		State.bSubmitQueries &= (FrameParity && IStereoRendering::IsAPrimaryView(View)) || (!FrameParity && IStereoRendering::IsASecondaryView(View));
	}

	// Disable HZB on OpenGL platforms to avoid rendering artifacts
	// It can be forced on by setting HZBOcclusion to 2
	State.bHZBOcclusion = !IsOpenGLPlatform(View.GetShaderPlatform());
	State.bHZBOcclusion &= FDataDrivenShaderPlatformInfo::GetSupportsHZBOcclusion(View.GetShaderPlatform());
	State.bHZBOcclusion &= GHZBOcclusion != 0;
	State.bHZBOcclusion |= GHZBOcclusion == 2;

	State.bUseRoundRobinOcclusion = bUseRoundRobinOcclusion;

	State.NumBufferedFrames = FOcclusionQueryHelpers::GetNumBufferedFrames(Scene.GetFeatureLevel());
	State.ReadBackLagTolerance = State.NumBufferedFrames;

	State.bAllowSubQueries = GAllowSubPrimitiveQueries && !View.bDisableQuerySubmissions;

	if (State.bUseRoundRobinOcclusion)
	{
		// Round-robin occlusion culling involves reading frames that could be twice as stale as without round-robin
		State.ReadBackLagTolerance = State.NumBufferedFrames * 2;
	}
}

void FGPUOcclusion::Map(FRHICommandListImmediate& RHICmdListImmediate)
{
	SCOPED_NAMED_EVENT(MapOcclusionResults, FColor::Magenta);

	if (ViewState.OcclusionFeedback.IsInitialized())
	{
		QUICK_SCOPE_CYCLE_COUNTER(STAT_OcclusionFeedback_ReadbackResults);
		ViewState.OcclusionFeedback.ReadbackResults(RHICmdListImmediate);
		ViewState.OcclusionFeedback.AdvanceFrame(ViewState.OcclusionFrameCounter);
	}
	else if (State.bHZBOcclusion)
	{
		QUICK_SCOPE_CYCLE_COUNTER(STAT_MapHZBResults);
		check(!ViewState.HZBOcclusionTests.IsValidFrame(ViewState.OcclusionFrameCounter));
		ViewState.HZBOcclusionTests.MapResults(RHICmdListImmediate);
	}

	ViewState.PrimitiveOcclusionQueryPool.AdvanceFrame(
		ViewState.OcclusionFrameCounter,
		FOcclusionQueryHelpers::GetNumBufferedFrames(Scene.GetFeatureLevel()),
		State.bUseRoundRobinOcclusion);

	ViewState.Occlusion.NumRequestedQueries = 0;
}

void FGPUOcclusion::Unmap(FRHICommandListImmediate& RHICmdListImmediate)
{
	if (State.bHZBOcclusion)
	{
		ViewState.HZBOcclusionTests.UnmapResults(RHICmdListImmediate);
	}

	if (View.FeatureLevel == ERHIFeatureLevel::ES3_1)
	{
		// Initialize/release OcclusionFeedback system on demand
		if (GOcclusionFeedback_Enable == 0 && ViewState.OcclusionFeedback.IsInitialized())
		{
			ViewState.OcclusionFeedback.ReleaseResource();
		}
		else if (GOcclusionFeedback_Enable != 0 && !ViewState.OcclusionFeedback.IsInitialized())
		{
			ViewState.OcclusionFeedback.InitResource(RHICmdListImmediate);
		}
	}

	if (State.bHZBOcclusion && State.bSubmitQueries)
	{
		ViewState.HZBOcclusionTests.SetValidFrameNumber(ViewState.OcclusionFrameCounter);
	}
}

void FGPUOcclusion::WaitForLastOcclusionQuery()
{
	const uint32 QueryIndex = FOcclusionQueryHelpers::GetQueryLookupIndex(ViewState.OcclusionFrameCounter, State.NumBufferedFrames);
	if (ViewState.Occlusion.LastOcclusionQueryArray[QueryIndex])
	{
		TRACE_CPUPROFILER_EVENT_SCOPE(GPUBound_WaitingForGPUForOcclusionQueries_SeeGPUTrack);

		uint64 Result;
		const bool bWait = true;
		RHIGetRenderQueryResult(ViewState.Occlusion.LastOcclusionQueryArray[QueryIndex], Result, bWait);
		ViewState.Occlusion.LastOcclusionQueryArray[QueryIndex] = nullptr;
	}
}

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

bool FGPUOcclusionParallelPacket::AddPrimitive(int32 PrimitiveIndex)
{
	EOcclusionFlags::Type OcclusionFlags;

	if (CanBeOccluded(PrimitiveIndex, OcclusionFlags))
	{
		Input.AddElement(PrimitiveIndex);
		int32 NumSubQueries = 1;

		if (EnumHasAnyFlags(OcclusionFlags, EOcclusionFlags::HasSubprimitiveQueries) && OcclusionState.bAllowSubQueries)
		{
			NumSubQueries = Scene.PrimitiveSceneProxies[PrimitiveIndex]->GetOcclusionQueries(&View)->Num();
		}

		NumInputSubQueries += NumSubQueries;
		return true;
	}

	View.PrimitiveDefinitelyUnoccludedMap[PrimitiveIndex].AtomicSet(true);
	return false;
}

void FGPUOcclusionParallelPacket::LaunchOcclusionCullTask()
{
	check(!bTaskLaunched);

	if (Input.IsEmpty())
	{
		return;
	}

	bTaskLaunched = true;

	ViewPacket.Relevance.CommandPipe.AddNumCommands(1);

	FVisibilityTaskConfig& TaskConfig = ViewPacket.TaskConfig;

	Task = UE::Tasks::Launch(UE_SOURCE_LOCATION, [this, &TaskConfig]
	{
		FTaskTagScope Scope(ETaskTag::EParallelRenderingThread);

		FPrimitiveIndexList PrimitiveIndexList;
		const FOcclusionCullResult Result = OcclusionCullTask(PrimitiveIndexList);

		if (PrimitiveIndexList.IsEmpty())
		{
			ViewPacket.Relevance.CommandPipe.ReleaseNumCommands(1);
		}
		else
		{
			ViewPacket.Relevance.CommandPipe.EnqueueCommand(MoveTemp(PrimitiveIndexList));
		}

		RecordOcclusionCullResult(Result);

	}, TaskConfig.OcclusionCull.TaskPriority);
}

FOcclusionCullResult FGPUOcclusionParallelPacket::OcclusionCullTask(FPrimitiveIndexList& PrimitiveIndexList)
{
	SCOPED_NAMED_EVENT(OcclusionCull, FColor::Magenta);

	FOcclusionCullResult Result;

	PrimitiveIndexList.Reserve(Input.Num());

	for (int32 Index : Input)
	{
		if (OcclusionCullPrimitive<true>(RecordVisitor, Result, Index))
		{
			PrimitiveIndexList.Emplace(Index);
		}
	}

	return Result;
}

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

void FGPUOcclusionParallel::AddPrimitives(FPrimitiveRange PrimitiveRange)
{
	WaitForLastOcclusionQuery();

	for (FSceneSetBitIterator BitIt(View.PrimitiveVisibilityMap, PrimitiveRange.StartIndex); BitIt.GetIndex() < PrimitiveRange.EndIndex; ++BitIt)
	{
		FGPUOcclusionParallelPacket* Packet = Packets.Last();

		if (Packet->AddPrimitive(BitIt.GetIndex()))
		{
			if (Packet->IsFull())
			{
				Packet->LaunchOcclusionCullTask();
				CreateOcclusionPacket();
			}
		}
		else
		{
			// The primitive will not be occluded, so accumulate a packet of primitives to send directly to the relevance pipe to reduce latency.
			NonOccludedPrimitives.Emplace(BitIt.GetIndex());

			if (NonOccludedPrimitives.Num() == MaxNonOccludedPrimitives)
			{
				ViewPacket.Relevance.CommandPipe.AddNumCommands(1);
				ViewPacket.Relevance.CommandPipe.EnqueueCommand(MoveTemp(NonOccludedPrimitives));
				NonOccludedPrimitives.Reset();
				NonOccludedPrimitives.Reserve(MaxNonOccludedPrimitives);
			}
		}
	}
}

void FGPUOcclusionParallel::Finish(UE::Tasks::FTaskEvent& OcclusionCullTasks)
{
	check(!bFinished);
	bFinished = true;

	Packets.Last()->LaunchOcclusionCullTask();

	if (!NonOccludedPrimitives.IsEmpty())
	{
		ViewPacket.Relevance.CommandPipe.AddNumCommands(1);
		ViewPacket.Relevance.CommandPipe.EnqueueCommand(MoveTemp(NonOccludedPrimitives));
		NonOccludedPrimitives.Reset();
	}

	for (FGPUOcclusionParallelPacket* Packet : Packets)
	{
		if (Packet->bTaskLaunched)
		{
			OcclusionCullTasks.AddPrerequisites(Packet->Task);
		}
	}

	OcclusionCullTasks.Trigger();
}

void FGPUOcclusionParallel::Finalize()
{
	check(bFinished);
	bFinalized = true;

	SCOPED_NAMED_EVENT(FinalizeOcclusionCull, FColor::Magenta);

	for (FGPUOcclusionParallelPacket* Packet : Packets)
	{
		FGPUOcclusionPacket::FProcessVisitor ProcessVisitor(*Packet, *RHICmdList, DynamicVertexBuffer);
		ProcessVisitor.Replay(Packet->RecordVisitor);
	}

	for (FGPUOcclusionParallelPacket* Packet : Packets)
	{
		// Wait to add occlusion histories until after replaying commands since it will invalidate pointers.
		for (FPrimitiveOcclusionHistory& OcclusionHistory : Packet->RecordVisitor.OcclusionHistories)
		{
			ViewState.Occlusion.PrimitiveOcclusionHistorySet.Add(OcclusionHistory);
		}

		delete Packet;
	}

	Packets.Empty();
	DynamicVertexBuffer.Commit();
	RHICmdList->FinishRecording();
	FinalizeTask.Trigger();
}

void FGPUOcclusionParallel::Map(FRHICommandListImmediate& RHICmdListImmediate)
{
	FGPUOcclusion::Map(RHICmdListImmediate);
	RHICmdList = new FRHICommandList(RHICmdListImmediate.GetGPUMask());
	RHICmdList->SwitchPipeline(ERHIPipeline::Graphics);
	DynamicVertexBuffer.Init(*RHICmdList);
}

void FGPUOcclusionParallel::Unmap(FRHICommandListImmediate& RHICmdListImmediate)
{
	FinalizeTask.Wait();
	check(bFinalized);
	RHICmdListImmediate.QueueAsyncCommandListSubmit(RHICmdList);
	FGPUOcclusion::Unmap(RHICmdListImmediate);
}

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

void FGPUOcclusionSerial::AddPrimitives(FPrimitiveRange PrimitiveRange)
{
	CSV_SCOPED_TIMING_STAT_EXCLUSIVE(FetchVisibilityForPrimitives);

	for (FSceneSetBitIterator BitIt(View.PrimitiveVisibilityMap, PrimitiveRange.StartIndex); BitIt.GetIndex() < PrimitiveRange.EndIndex; ++BitIt)
	{
		EOcclusionFlags::Type OcclusionFlags;
		if (Packet.CanBeOccluded(BitIt.GetIndex(), OcclusionFlags))
		{
			Packet.OcclusionCullPrimitive<false>(ProcessVisitor, OcclusionCullResult, BitIt.GetIndex());
		}
		else
		{
			View.PrimitiveDefinitelyUnoccludedMap.AccessCorrespondingBit(BitIt) = true;
		}
	}
}

void FGPUOcclusionSerial::Map(FRHICommandListImmediate& RHICmdListImmediate)
{
	FGPUOcclusion::Map(RHICmdListImmediate);
	DynamicVertexBuffer.Init(RHICmdListImmediate);
}

void FGPUOcclusionSerial::Unmap(FRHICommandListImmediate& RHICmdListImmediate)
{
	DynamicVertexBuffer.Commit();
	ProcessVisitor.SubmitThrottledOcclusionQueries();
	Packet.RecordOcclusionCullResult(OcclusionCullResult);
	FGPUOcclusion::Unmap(RHICmdListImmediate);
}

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

static int32 PrecomputedOcclusionCull(FVisibilityViewPacket& ViewPacket, FPrimitiveRange PrimitiveRange)
{
	int32 NumOccludedPrimitives = 0;

	const FScene& Scene = ViewPacket.Scene;
	FViewInfo& View = ViewPacket.View;

	if (View.PrecomputedVisibilityData)
	{
		SCOPED_NAMED_EVENT(PrecomputedOcclusionCull, FColor::Magenta);
		QUICK_SCOPE_CYCLE_COUNTER(STAT_PrecomputedOcclusionCull);

		uint8 PrecomputedVisibilityFlags = EOcclusionFlags::CanBeOccluded | EOcclusionFlags::HasPrecomputedVisibility;
		for (FSceneSetBitIterator BitIt(View.PrimitiveVisibilityMap, PrimitiveRange.StartIndex); BitIt.GetIndex() < PrimitiveRange.EndIndex; ++BitIt)
		{
			if ((Scene.PrimitiveOcclusionFlags[BitIt.GetIndex()] & PrecomputedVisibilityFlags) == PrecomputedVisibilityFlags)
			{
				FPrimitiveVisibilityId VisibilityId = Scene.PrimitiveVisibilityIds[BitIt.GetIndex()];
				if ((View.PrecomputedVisibilityData[VisibilityId.ByteIndex] & VisibilityId.BitMask) == 0)
				{
					if (GVisualizeOccludedPrimitives)
					{
						const FBoxSphereBounds& Bounds = Scene.PrimitiveOcclusionBounds[BitIt.GetIndex()];
						DrawWireBox(&ViewPacket.ViewElementPDI, Bounds.GetBox(), FColor(100, 50, 50), SDPG_Foreground);
					}

					View.PrimitiveVisibilityMap.AccessCorrespondingBit(BitIt) = false;
					INC_DWORD_STAT_BY(STAT_StaticallyOccludedPrimitives, 1);
					NumOccludedPrimitives++;
				}
			}
		}
	}

	return NumOccludedPrimitives;
}

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

FVisibilityTaskConfig::FVisibilityTaskConfig(const FScene& Scene, TConstArrayView<FViewInfo*> Views)
{
	Schedule = GVisibilityTaskSchedule != 0 ? EVisibilityTaskSchedule::Parallel : EVisibilityTaskSchedule::RenderThread;

	if (Schedule == EVisibilityTaskSchedule::Parallel)
	{
		if (!FApp::ShouldUseThreadingForPerformance() || !GIsThreadedRendering || !GSupportsParallelOcclusionQueries || GVisualizeOccludedPrimitives > 0 || IsMobilePlatform(Scene.GetShaderPlatform()))
		{
			Schedule = EVisibilityTaskSchedule::RenderThread;
		}
	}

	NumTestedPrimitives = uint32(Scene.Primitives.Num());
	NumVisiblePrimitives = 0u;

	if (Scene.PrimitivesAlwaysVisibleOffset != ~0u)
	{
		NumTestedPrimitives  = Scene.PrimitivesAlwaysVisibleOffset;
		NumVisiblePrimitives = uint32(Scene.Primitives.Num()) - NumTestedPrimitives;

		// Ensure that the dword alignment code is correct and we never have partial dword offsets
		check(uint32(NumTestedPrimitives % NumBitsPerDWORD) == 0u);
	}

	const uint32 NumWorkerThreads = FMath::Min(LowLevelTasks::FScheduler::Get().GetNumWorkers(), 16u);

	// These values tune the task granularity based on number of primitives in the scene and the number of worker tasks available.
	const uint32 NumAlwaysVisibleTasksPerThread = 2;
	const uint32 NumFrustumCullTasksPerThread   = 2;
	const uint32 NumOcclusionCullTasksPerThread = 2;
	const uint32 NumRelevanceTasksPerThread     = 32;

	const uint32 NumWordsPerTaskIfRenderThread = 128;

	// Always Visible
	if (NumVisiblePrimitives > 0u)
	{
		const uint32 NumPrimitiveWords = FMath::DivideAndRoundUp<uint32>(NumVisiblePrimitives, NumBitsPerDWORD);

		if (Schedule == EVisibilityTaskSchedule::RenderThread)
		{
			AlwaysVisible.NumWordsPerTask = NumWordsPerTaskIfRenderThread;
		}
		else
		{
			AlwaysVisible.NumWordsPerTask = FMath::DivideAndRoundUp(NumPrimitiveWords, NumWorkerThreads * NumAlwaysVisibleTasksPerThread);
		}

		AlwaysVisible.NumWordsPerTask = FMath::Clamp(AlwaysVisible.NumWordsPerTask, AlwaysVisible.MinWordsPerTask, NumPrimitiveWords);
		AlwaysVisible.NumPrimitivesPerTask = AlwaysVisible.NumWordsPerTask * NumBitsPerDWORD;
		AlwaysVisible.NumTasks = FMath::DivideAndRoundUp(NumVisiblePrimitives, AlwaysVisible.NumPrimitivesPerTask);
	}
	else
	{
		AlwaysVisible.NumWordsPerTask = 0;
		AlwaysVisible.NumPrimitivesPerTask = 0;
		AlwaysVisible.NumTasks = 0;
	}

	// Frustum Cull
	{
		const uint32 NumPrimitiveWords = FMath::DivideAndRoundUp<uint32>(NumTestedPrimitives, NumBitsPerDWORD);

		if (GFrustumCullNumPrimitivesPerTask > 0)
		{
			FrustumCull.NumWordsPerTask = FMath::DivideAndRoundUp<uint32>(GFrustumCullNumPrimitivesPerTask, NumBitsPerDWORD);
		}
		else if (Schedule == EVisibilityTaskSchedule::RenderThread)
		{
			FrustumCull.NumWordsPerTask = NumWordsPerTaskIfRenderThread;
		}
		else
		{
			FrustumCull.NumWordsPerTask = FMath::DivideAndRoundUp(NumPrimitiveWords, NumWorkerThreads * NumFrustumCullTasksPerThread);
		}

		FrustumCull.NumWordsPerTask = FMath::Clamp(FrustumCull.NumWordsPerTask, FrustumCull.MinWordsPerTask, NumPrimitiveWords);
		FrustumCull.NumPrimitivesPerTask = FrustumCull.NumWordsPerTask * NumBitsPerDWORD;
		FrustumCull.NumTasks = FMath::DivideAndRoundUp(NumTestedPrimitives, FrustumCull.NumPrimitivesPerTask);
	}

	// Occlusion Cull
	{
		OcclusionCull.Views.SetNum(Views.Num());

		for (int32 ViewIndex = 0; ViewIndex < Views.Num(); ++ViewIndex)
		{
			uint32& MaxQueriesPerTask = OcclusionCull.Views[ViewIndex].MaxQueriesPerTask;

			if (GOcclusionCullMaxQueriesPerTask > 0)
			{
				MaxQueriesPerTask = GOcclusionCullMaxQueriesPerTask;
			}
			else if (FSceneViewState* ViewState = static_cast<FSceneViewState*>(Views[ViewIndex]->State))
			{
				MaxQueriesPerTask = FMath::DivideAndRoundUp(ViewState->Occlusion.NumRequestedQueries, FMath::Max(1u, NumWorkerThreads) * NumOcclusionCullTasksPerThread);
			}

			MaxQueriesPerTask = FMath::Max(MaxQueriesPerTask, OcclusionCull.MinQueriesPerTask);
		}
	}

	// Relevance
	{
		const uint32 NumPrimitivesPerPacketIfRenderThread = 128;

		if (GRelevanceNumPrimitivesPerPacket > 0)
		{
			Relevance.NumPrimitivesPerPacket = GRelevanceNumPrimitivesPerPacket;
		}
		else if (Schedule == EVisibilityTaskSchedule::RenderThread)
		{
			Relevance.NumPrimitivesPerPacket = NumPrimitivesPerPacketIfRenderThread;
		}
		else
		{
			Relevance.NumPrimitivesPerPacket = FMath::DivideAndRoundUp(NumTestedPrimitives, NumWorkerThreads * NumRelevanceTasksPerThread);
		}

		Relevance.NumPrimitivesPerPacket = FMath::Clamp(Relevance.NumPrimitivesPerPacket, Relevance.MinPrimitivesPerTask, Relevance.MaxPrimitivesPerTask);
		Relevance.NumEstimatedPackets = FMath::DivideAndRoundUp(NumTestedPrimitives, Relevance.NumPrimitivesPerPacket);
	}
}

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

FVisibilityViewPacket::FVisibilityViewPacket(FVisibilityTaskData& InTaskData, FScene& InScene, FViewInfo& InView, int32 InViewIndex)
	: TaskData(InTaskData)
	, TaskConfig(TaskData.TaskConfig)
	, Scene(InScene)
	, View(InView)
	, ViewState(static_cast<FSceneViewState*>(View.ViewState))
	, ViewIndex(InViewIndex)
	, ViewElementPDI(&View, nullptr, nullptr)
{
	if (ViewState && !View.Family->EngineShowFlags.Wireframe && GOcclusionCullEnabled)
	{
		if (TaskConfig.Schedule == EVisibilityTaskSchedule::Parallel)
		{
			OcclusionCull.ContextIfParallel = TaskData.Allocator.Create<FGPUOcclusionParallel>(*this);
		}
		else
		{
			OcclusionCull.ContextIfSerial = TaskData.Allocator.Create<FGPUOcclusionSerial>(*this);
		}
	}

	if (TaskConfig.Schedule == EVisibilityTaskSchedule::Parallel)
	{
		// Chain the frustum cull task to the relevance task since we only wait on relevance.
		Tasks.ComputeRelevance.AddPrerequisites(Tasks.FrustumCull);

		// Callback for when an occlusion command is queued from frustum culling.
		OcclusionCull.CommandPipe.SetCommandFunction([this](FPrimitiveRange PrimitiveRange)
		{
			UpdatePrimitiveFading(Scene, View, ViewState, PrimitiveRange);

			const int32 NumCulledPrimitives = PrecomputedOcclusionCull(*this, PrimitiveRange);

			if (OcclusionCull.ContextIfParallel)
			{
				OcclusionCull.ContextIfParallel->AddPrimitives(PrimitiveRange);
			}
			else
			{
				// When occlusion is disabled primitives are queued directly to the relevance context rather than as a command on the relevance pipe.
				for (FSceneSetBitIterator BitIt(View.PrimitiveVisibilityMap, PrimitiveRange.StartIndex); BitIt.GetIndex() < PrimitiveRange.EndIndex; ++BitIt)
				{
					Relevance.Context->AddPrimitive(BitIt.GetIndex());
				}
			}

			TaskConfig.OcclusionCull.NumCulledPrimitives.fetch_add(NumCulledPrimitives, std::memory_order_relaxed);
		});

		// Callback for when the occlusion pipe is done accepting commands.
		OcclusionCull.CommandPipe.SetEmptyFunction([this]
		{
			if (OcclusionCull.ContextIfParallel)
			{
				OcclusionCull.ContextIfParallel->Finish(Tasks.OcclusionCull);

				// Launch a follow-up task to finalize occlusion results after all occlusion packets have completed.
				UE::Tasks::Launch(UE_SOURCE_LOCATION, [this]
				{
					FTaskTagScope Scope(ETaskTag::EParallelRenderingThread);
					Relevance.CommandPipe.ReleaseNumCommands(1);
					OcclusionCull.ContextIfParallel->Finalize();

				}, Tasks.OcclusionCull, TaskConfig.OcclusionCull.FinalizeTaskPriority);
			}
			else
			{
				Relevance.CommandPipe.ReleaseNumCommands(1);
				Tasks.OcclusionCull.Trigger();
			}
		});

		// Take a reference on the occlusion command pipe that is released when all frustum cull commands are enqueued.
		OcclusionCull.CommandPipe.AddNumCommands(1);

		// Callback for when a relevance command is queued from occlusion.
		Relevance.CommandPipe.SetCommandFunction([this](FPrimitiveIndexList&& PrimitiveIndexList)
		{
			Relevance.Context->AddPrimitives(MoveTemp(PrimitiveIndexList));
		});

		// Callback for when the relevance pipe is done accepting commands.
		Relevance.CommandPipe.SetEmptyFunction([this]
		{
			Relevance.Context->Finish(Tasks.ComputeRelevance);

			// Only used in the ViewPackets.Num() == 1 case
			if (TaskData.DynamicMeshElements.CommandPipe)
			{
				TaskData.DynamicMeshElements.CommandPipe->ReleaseNumCommands(1);
			}
		});

		// Take a reference on the relevance command pipe that is released by the occlusion pipe when all occlusion commands are complete.
		Relevance.CommandPipe.AddNumCommands(1);
	}
}

void FVisibilityViewPacket::BeginInitVisibility()
{
	TRACE_CPUPROFILER_EVENT_SCOPE_TEXT(*FString::Printf(TEXT("BeginInitVisibility %d"), ViewIndex));

	// Mark all primitives as visible when not visibility culling
	bool bShouldVisibilityCull = GFrustumCullEnabled;

	UE::Tasks::FTaskEvent RelevancePrereqs{ UE_SOURCE_LOCATION };
	RelevancePrereqs.AddPrerequisites(Scene.GetCacheMeshDrawCommandsTask());

	// Offload initialization of maps that are not touched by frustum culling / occlusion until the relevance phase. These can be quite expensive to zero out.
	RelevancePrereqs.AddPrerequisites(UE::Tasks::Launch(UE_SOURCE_LOCATION, [this]
	{
		TRACE_CPUPROFILER_EVENT_SCOPE(SceneVisibility_InitMaps);
		View.DynamicMeshElementRanges.SetNumZeroed(Scene.Primitives.Num());
		View.PrimitivesLODMask.Init(FLODMask(), Scene.Primitives.Num());
		View.StaticMeshVisibilityMap.Init(false, Scene.StaticMeshes.GetMaxIndex());
		View.StaticMeshFadeOutDitheredLODMap.Init(false, Scene.StaticMeshes.GetMaxIndex());
		View.StaticMeshFadeInDitheredLODMap.Init(false, Scene.StaticMeshes.GetMaxIndex());

	}, TaskConfig.TaskPriority));

	// Allocate the view's visibility maps.
	View.PrimitiveVisibilityMap.Init(!bShouldVisibilityCull, Scene.Primitives.Num());
	View.PrimitiveRayTracingVisibilityMap.Init(false, Scene.Primitives.Num());
	View.PrimitiveDefinitelyUnoccludedMap.Init(!GOcclusionCullEnabled, Scene.Primitives.Num());
	View.PotentiallyFadingPrimitiveMap.Init(false, Scene.Primitives.Num());
	View.PrimitiveFadeUniformBuffers.AddZeroed(Scene.Primitives.Num());
	View.PrimitiveFadeUniformBufferMap.Init(false, Scene.Primitives.Num());
	View.PrimitiveViewRelevanceMap.Reset(Scene.Primitives.Num());
	View.PrimitiveViewRelevanceMap.AddZeroed(Scene.Primitives.Num());

	RelevancePrereqs.Trigger();

	if (View.ShowOnlyPrimitives.IsSet())
	{
		View.bHasNoVisiblePrimitive = View.ShowOnlyPrimitives->Num() == 0;
	}

	Relevance.Context = TaskData.Allocator.Create<FComputeAndMarkRelevance>(TaskData, Scene, View, ViewIndex, RelevancePrereqs);

	ClearStalePrimitiveFadingStates(View, ViewState);

	// Development builds sometimes override frustum culling, e.g. dependent views in the editor.
#if !(UE_BUILD_SHIPPING || UE_BUILD_TEST)
	if (ViewState)
	{
		// For views with frozen visibility, check if the primitive is in the frozen visibility set.
		if (ViewState->bIsFrozen)
		{
			bShouldVisibilityCull = false;
			for (int32 Index = 0; Index < int32(TaskConfig.NumTestedPrimitives); ++Index)
			{
				if (ViewState->FrozenPrimitives.Contains(Scene.PrimitiveComponentIds[Index]))
				{
					View.PrimitiveVisibilityMap[Index] = true;
				}
			}
		}
	}
#endif

	const float MaxDrawDistanceScale = GetCachedScalabilityCVars().ViewDistanceScale * GetCachedScalabilityCVars().CalculateFieldOfViewDistanceScale(View.DesiredFOV);
	const FHLODVisibilityState* HLODState = nullptr;

	// Most views use standard frustum culling.
	if (bShouldVisibilityCull)
	{
		TRACE_CPUPROFILER_EVENT_SCOPE(HLODInit);

		// Update HLOD transition/visibility states to allow use during distance culling
		FLODSceneTree& HLODTree = Scene.SceneLODHierarchy;

		if (HLODTree.IsActive())
		{
			HLODTree.UpdateVisibilityStates(View, Tasks.LightVisibility);

			if (ViewState)
			{
				HLODState = &ViewState->HLODVisibilityState;
			}
		}
		else
		{
			HLODTree.ClearVisibilityState(View);
		}
	}

	Tasks.LightVisibility.Trigger();

	FFrustumCullingFlags Flags;
	Flags.bShouldVisibilityCull  = bShouldVisibilityCull;
	Flags.bUseCustomCulling      = View.CustomVisibilityQuery && View.CustomVisibilityQuery->Prepare();
	Flags.bUseSphereTestFirst    = GFrustumCullUseSphereTestFirst;
	Flags.bUseFastIntersect      = (View.GetCullingFrustum().PermutedPlanes.Num() == 8) && GFrustumCullUseFastIntersect;
	Flags.bUseVisibilityOctree   = GFrustumCullUseOctree;
	Flags.bHasHiddenPrimitives   = View.HiddenPrimitives.Num() > 0;
	Flags.bHasShowOnlyPrimitives = View.ShowOnlyPrimitives.IsSet();

	UE::Tasks::FTask PrerequisiteTask;

#if RHI_RAYTRACING
	View.RayTracingCullingParameters.Init(View);

	// Sync cached raytracing tasks ShouldCullForRayTracing.
	PrerequisiteTask = Scene.GetCacheRayTracingPrimitivesTask();
#endif

	FSceneBitArray* VisibleNodes = nullptr;

	if (bShouldVisibilityCull && Flags.bUseVisibilityOctree)
	{
		VisibleNodes = TaskData.Allocator.Create<FSceneBitArray>();
		const FConvexVolume& ViewCullingFrustum = View.GetCullingFrustum();
		CullOctree(Scene, View, Flags, *VisibleNodes, ViewCullingFrustum);
	}

	const bool bCullingIsThreadsafe = (!Flags.bUseCustomCulling || View.CustomVisibilityQuery->IsThreadsafe());

	if (TaskConfig.Schedule == EVisibilityTaskSchedule::Parallel)
	{
		// Always Visible
		const bool bHasAlwaysVisible = TaskConfig.NumVisiblePrimitives > 0;
		if (bHasAlwaysVisible)
		{
			const float CurrentWorldTime = View.Family->Time.GetWorldTimeSeconds();
			for (uint32 TaskIndex = 0; TaskIndex < TaskConfig.AlwaysVisible.NumTasks; ++TaskIndex)
			{
				Tasks.AlwaysVisible.AddPrerequisites(
					UE::Tasks::Launch(UE_SOURCE_LOCATION, [this, Flags, TaskIndex, CurrentWorldTime]() mutable
				{
					TRACE_CPUPROFILER_EVENT_SCOPE(SceneVisibility_AlwaysVisible);
					SCOPE_CYCLE_COUNTER(STAT_UpdateAlwaysVisible);

					FTaskTagScope TaskTagScope(ETaskTag::EParallelRenderingThread);
					UpdateAlwaysVisible(Scene, View, Flags, TaskConfig, TaskIndex, CurrentWorldTime);

				}, PrerequisiteTask, TaskConfig.TaskPriority, UE::Tasks::EExtendedTaskPriority::None));
			}
		}

		// Frustum Cull
		{
			// Frustum culling tasks have to run serially if custom culling is not thread-safe.
			const UE::Tasks::EExtendedTaskPriority ExtendedTaskPriority = GetExtendedTaskPriority(bCullingIsThreadsafe);

			// Assign the number of expected commands first so the pipe can determine when the last task has completed.
			OcclusionCull.CommandPipe.AddNumCommands(TaskConfig.FrustumCull.NumTasks);

			for (uint32 TaskIndex = 0; TaskIndex < TaskConfig.FrustumCull.NumTasks; ++TaskIndex)
			{
				Tasks.FrustumCull.AddPrerequisites(
					UE::Tasks::Launch(UE_SOURCE_LOCATION, [this, Flags, MaxDrawDistanceScale, HLODState, VisibleNodes, TaskIndex]() mutable
				{
					TRACE_CPUPROFILER_EVENT_SCOPE(SceneVisibility_FrustumCull);
					FTaskTagScope TaskTagScope(ETaskTag::EParallelRenderingThread);
					int32 NumCulledPrimitives = FrustumCull(Scene, View, Flags, MaxDrawDistanceScale, HLODState, VisibleNodes, TaskConfig, TaskIndex);

					FPrimitiveRange PrimitiveRange;
					PrimitiveRange.StartIndex = TaskConfig.FrustumCull.NumPrimitivesPerTask * (TaskIndex);
					PrimitiveRange.EndIndex   = TaskConfig.FrustumCull.NumPrimitivesPerTask + PrimitiveRange.StartIndex;
					PrimitiveRange.EndIndex   = FMath::Min(PrimitiveRange.EndIndex, int32(TaskConfig.NumTestedPrimitives));

					// Skip rendering of dynamic objects without static lighting for static reflection captures.
					if (View.bStaticSceneOnly)
					{
						for (FSceneSetBitIterator BitIt(View.PrimitiveVisibilityMap, PrimitiveRange.StartIndex); BitIt.GetIndex() < PrimitiveRange.EndIndex; ++BitIt)
						{
							if (!Scene.PrimitiveSceneProxies[BitIt.GetIndex()]->HasStaticLighting())
							{
								View.PrimitiveVisibilityMap.AccessCorrespondingBit(BitIt) = false;
								NumCulledPrimitives++;
							}
						}
					}

					// Skip rendering of small objects when in wireframe mode for performance since wireframe doesn't enable occlusion culling.
					if (View.Family->EngineShowFlags.Wireframe)
					{
						const float ScreenSizeScale = FMath::Max(View.ViewMatrices.GetProjectionMatrix().M[0][0] * View.ViewRect.Width(), View.ViewMatrices.GetProjectionMatrix().M[1][1] * View.ViewRect.Height());

						for (FSceneSetBitIterator BitIt(View.PrimitiveVisibilityMap, PrimitiveRange.StartIndex); BitIt.GetIndex() < PrimitiveRange.EndIndex; ++BitIt)
						{
							if (ScreenSizeScale * Scene.PrimitiveBounds[BitIt.GetIndex()].BoxSphereBounds.SphereRadius <= GWireframeCullThreshold)
							{
								View.PrimitiveVisibilityMap.AccessCorrespondingBit(BitIt) = false;
								NumCulledPrimitives++;
							}
						}
					}

					const uint32 NumVisiblePrimitives = PrimitiveRange.EndIndex - PrimitiveRange.StartIndex - NumCulledPrimitives;

					if (NumVisiblePrimitives == 0)
					{
						OcclusionCull.CommandPipe.ReleaseNumCommands(1);
					}
					else
					{
						OcclusionCull.CommandPipe.EnqueueCommand(PrimitiveRange);
					}

					TaskConfig.FrustumCull.NumCulledPrimitives.fetch_add(NumCulledPrimitives, std::memory_order_relaxed);

				}, bHasAlwaysVisible ? Tasks.AlwaysVisible : PrerequisiteTask, TaskConfig.TaskPriority, ExtendedTaskPriority));
			}

			OcclusionCull.CommandPipe.ReleaseNumCommands(1);
		}
	}
	else
	{
		const bool bSingleThreaded = !FApp::ShouldUseThreadingForPerformance() || !bCullingIsThreadsafe;

		PrerequisiteTask.Wait();

		const float CurrentWorldTime = View.Family->Time.GetWorldTimeSeconds();
		ParallelFor(TaskConfig.AlwaysVisible.NumTasks, [this, Flags, CurrentWorldTime](int32 TaskIndex)
		{
			TRACE_CPUPROFILER_EVENT_SCOPE(SceneVisibility_AlwaysVisible);
			FTaskTagScope TaskTagScope(ETaskTag::EParallelRenderingThread);
			UpdateAlwaysVisible(Scene, View, Flags, TaskConfig, TaskIndex, CurrentWorldTime);

		}, bSingleThreaded);

		ParallelFor(TaskConfig.FrustumCull.NumTasks, [this, Flags, MaxDrawDistanceScale, HLODState, VisibleNodes](int32 TaskIndex)
		{
			TRACE_CPUPROFILER_EVENT_SCOPE(SceneVisibility_FrustumCull);
			FTaskTagScope TaskTagScope(ETaskTag::EParallelRenderingThread);
			int32 NumCulledPrimitives = FrustumCull(Scene, View, Flags, MaxDrawDistanceScale, HLODState, VisibleNodes, TaskConfig, TaskIndex);
			TaskConfig.FrustumCull.NumCulledPrimitives.fetch_add(NumCulledPrimitives, std::memory_order_relaxed);

		}, bSingleThreaded);
	}

	Tasks.AlwaysVisible.Trigger();
	Tasks.FrustumCull.Trigger();
}

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

FDynamicMeshElementContext::FDynamicMeshElementContext(FSceneRenderer& SceneRenderer)
	: FirstViewFamily(SceneRenderer.ViewFamily)
	, Views(SceneRenderer.AllViews)
	, Primitives(SceneRenderer.Scene->Primitives)
	// Defer committing GPU scene and Material updates until the mesh collectors are finished. Deferring materials allows VT updates to
	// overlap with GDME (uniform expression updates can't happen at the same time as the async VT system update), and since we are going
	// wide across a single view we would otherwise have to lock for GPU scene updates.
	, MeshCollector(SceneRenderer.FeatureLevel, SceneRenderer.Allocator, FMeshElementCollector::ECommitFlags::DeferAll)
#if WITH_EDITOR
	, EditorMeshCollector(SceneRenderer.FeatureLevel, SceneRenderer.Allocator, FMeshElementCollector::ECommitFlags::DeferAll)
#endif
	, RHICmdList(new FRHICommandList(FRHIGPUMask::All()))
	, DynamicVertexBuffer(*RHICmdList)
	, DynamicIndexBuffer(*RHICmdList)
{
	// With Custom Render Passes, it's possible to have Views that point to a different Family.  Divide Views into groups with the same family.
	uint8 ViewSubsetMask = 0;
	int32 LastViewIndex = Views.Num() - 1;
	for (int32 ViewIndex = 0; ViewIndex <= LastViewIndex; ViewIndex++)
	{
		ViewSubsetMask |= 1u << ViewIndex;

		// Check if the next element has a different ViewFamily, or this is the last view.  If so, emit the GetDynamicMeshElements call
		// with visibility mask bits set for the subset of views with the same ViewFamily, and reset the mask for the next family.
		if (ViewIndex == LastViewIndex || Views[ViewIndex]->Family != Views[ViewIndex + 1]->Family)
		{
			// Emit a batch with the given mask, and reset the mask
			ViewFamilyGroups.Add({ Views[ViewIndex]->Family, ViewSubsetMask });
			ViewSubsetMask = 0;
		}
	}

	RHICmdList->SwitchPipeline(ERHIPipeline::Graphics);

	ViewMeshArraysPerView.SetNum(Views.Num());

	MeshCollector.Start(
		*RHICmdList,
		DynamicVertexBuffer,
		DynamicIndexBuffer,
		SceneRenderer.DynamicReadBufferForInitViews
	);

	for (int32 ViewIndex = 0; ViewIndex < Views.Num(); ViewIndex++)
	{
		FViewInfo& View = *Views[ViewIndex];
		FViewMeshArrays& ViewMeshArrays = ViewMeshArraysPerView[ViewIndex];

		MeshCollector.AddViewMeshArrays(
			&View,
			&ViewMeshArrays.DynamicMeshElements,
			&ViewMeshArrays.SimpleElementCollector,
			&View.DynamicPrimitiveCollector
#if UE_ENABLE_DEBUG_DRAWING
			, &ViewMeshArrays.DebugSimpleElementCollector
#endif
		);
	}

#if WITH_EDITOR
	if (GIsEditor)
	{
		EditorMeshCollector.Start(
			*RHICmdList,
			DynamicVertexBuffer,
			DynamicIndexBuffer,
			SceneRenderer.DynamicReadBufferForInitViews
		);

		for (int32 ViewIndex = 0; ViewIndex < Views.Num(); ViewIndex++)
		{
			FViewInfo& View = *Views[ViewIndex];
			FViewMeshArrays& ViewMeshArrays = ViewMeshArraysPerView[ViewIndex];

			EditorMeshCollector.AddViewMeshArrays(
				&View,
				&ViewMeshArrays.DynamicEditorMeshElements,
				&ViewMeshArrays.EditorSimpleElementCollector,
				&View.DynamicPrimitiveCollector
#if UE_ENABLE_DEBUG_DRAWING
				, &ViewMeshArrays.DebugSimpleElementCollector
#endif
			);
		}
	}
#endif
}

FGraphEventRef FDynamicMeshElementContext::LaunchRenderThreadTask(FDynamicPrimitiveIndexList&& PrimitiveIndexList)
{
	return FFunctionGraphTask::CreateAndDispatchWhenReady([this, PrimitiveIndexList = MoveTemp(PrimitiveIndexList)]
	{
		for (FDynamicPrimitiveIndex PrimitiveIndex : PrimitiveIndexList.Primitives)
		{
			GatherDynamicMeshElementsForPrimitive(Primitives[PrimitiveIndex.Index], PrimitiveIndex.ViewMask);
		}

#if WITH_EDITOR
		for (FDynamicPrimitiveIndex PrimitiveIndex : PrimitiveIndexList.EditorPrimitives)
		{
			GatherDynamicMeshElementsForEditorPrimitive(Primitives[PrimitiveIndex.Index], PrimitiveIndex.ViewMask);
		}
#endif
	}, TStatId{}, nullptr, ENamedThreads::GetRenderThread_Local());
}

UE::Tasks::FTask FDynamicMeshElementContext::LaunchAsyncTask(FDynamicPrimitiveIndexQueue* PrimitiveIndexQueue, UE::Tasks::ETaskPriority TaskPriority)
{
	return Pipe.Launch(UE_SOURCE_LOCATION, [this, PrimitiveIndexQueue]
	{
		FTaskTagScope Scope(ETaskTag::EParallelRenderingThread);
		FDynamicPrimitiveIndex PrimitiveIndex;

		while (PrimitiveIndexQueue->Pop(PrimitiveIndex))
		{
			GatherDynamicMeshElementsForPrimitive(Primitives[PrimitiveIndex.Index], PrimitiveIndex.ViewMask);
		}

#if WITH_EDITOR
		while (PrimitiveIndexQueue->PopEditor(PrimitiveIndex))
		{
			GatherDynamicMeshElementsForEditorPrimitive(Primitives[PrimitiveIndex.Index], PrimitiveIndex.ViewMask);
		}
#endif
	}, TaskPriority);
}

void FDynamicMeshElementContext::GatherDynamicMeshElementsForPrimitive(FPrimitiveSceneInfo* Primitive, uint8 ViewMask)
{
	SCOPED_NAMED_EVENT(DynamicPrimitive, FColor::Magenta);

	TArray<int32, TInlineAllocator<4>> MeshBatchCountBefore;
	MeshBatchCountBefore.SetNumUninitialized(Views.Num());
	for (int32 ViewIndex = 0; ViewIndex < Views.Num(); ViewIndex++)
	{
		MeshBatchCountBefore[ViewIndex] = MeshCollector.GetMeshBatchCount(ViewIndex);
	}

	MeshCollector.SetPrimitive(Primitive->Proxy, Primitive->DefaultDynamicHitProxyId);

	// If Custom Render Passes aren't in use, there will be only one group, which is the common case.
	if (ViewFamilyGroups.Num() == 1 || Primitive->Proxy->SinglePassGDME())
	{
		Primitive->Proxy->GetDynamicMeshElements(FirstViewFamily.AllViews, FirstViewFamily, ViewMask, MeshCollector);
	}
	else
	{
		for (FViewFamilyGroup& Group : ViewFamilyGroups)
		{
			if (uint8 MaskedViewMask = ViewMask & Group.ViewSubsetMask)
			{
				Primitive->Proxy->GetDynamicMeshElements(FirstViewFamily.AllViews, *Group.Family, MaskedViewMask, MeshCollector);
			}
		}
	}

	for (int32 ViewIndex = 0; ViewIndex < Views.Num(); ViewIndex++)
	{
		FViewInfo& View = *Views[ViewIndex];

		if (ViewMask & (1 << ViewIndex))
		{
			FDynamicPrimitive& DynamicPrimitive = DynamicPrimitives.Emplace_GetRef();
			DynamicPrimitive.PrimitiveIndex = Primitive->GetIndex();
			DynamicPrimitive.ViewIndex = ViewIndex;
			DynamicPrimitive.StartElementIndex = MeshBatchCountBefore[ViewIndex];
			DynamicPrimitive.EndElementIndex = MeshCollector.GetMeshBatchCount(ViewIndex);
		}
	}
}

void FDynamicMeshElementContext::GatherDynamicMeshElementsForEditorPrimitive(FPrimitiveSceneInfo* Primitive, uint8 ViewMask)
{
#if WITH_EDITOR
	EditorMeshCollector.SetPrimitive(Primitive->Proxy, Primitive->DefaultDynamicHitProxyId);

	// If Custom Render Passes aren't in use, there will be only one group, which is the common case.
	if (ViewFamilyGroups.Num() == 1 || Primitive->Proxy->SinglePassGDME())
	{
		Primitive->Proxy->GetDynamicMeshElements(FirstViewFamily.AllViews, FirstViewFamily, ViewMask, EditorMeshCollector);
	}
	else
	{
		for (FViewFamilyGroup& Group : ViewFamilyGroups)
		{
			if (uint8 MaskedViewMask = ViewMask & Group.ViewSubsetMask)
			{
				Primitive->Proxy->GetDynamicMeshElements(FirstViewFamily.AllViews, *Group.Family, MaskedViewMask, EditorMeshCollector);
			}
		}
	}
#endif
}

void FDynamicMeshElementContext::Finish()
{
	MeshCollector.Finish();

#if WITH_EDITOR
	if (GIsEditor)
	{
		EditorMeshCollector.Finish();
	}
#endif

	DynamicVertexBuffer.Commit();
	DynamicIndexBuffer.Commit();
	RHICmdList->FinishRecording();

	// Even though task dependencies are setup so all work is done by this point, we still have to wait on the
	// pipe to clear out its internal state. Otherwise it can assert that it still has work at shutdown.
	Pipe.WaitUntilEmpty();
}

FDynamicMeshElementContextContainer::~FDynamicMeshElementContextContainer()
{
	check(CommandLists.IsEmpty());
}

UE::Tasks::FTask FDynamicMeshElementContextContainer::LaunchAsyncTask(FDynamicPrimitiveIndexQueue* PrimitiveIndexQueue, int32 Index, UE::Tasks::ETaskPriority TaskPriority)
{
	return Contexts[Index]->LaunchAsyncTask(PrimitiveIndexQueue, TaskPriority);
}

FGraphEventRef FDynamicMeshElementContextContainer::LaunchRenderThreadTask(FDynamicPrimitiveIndexList&& PrimitiveIndexList)
{
	return Contexts.Last()->LaunchRenderThreadTask(MoveTemp(PrimitiveIndexList));
}

void FDynamicMeshElementContextContainer::Init(FSceneRenderer& SceneRenderer, int32 NumAsyncContexts)
{
	const int32 NumRenderThreadContexts = 1;
	const int32 NumContexts = NumAsyncContexts + NumRenderThreadContexts;
	Views = SceneRenderer.AllViews;
	Contexts.Reserve(NumContexts);
	CommandLists.Reserve(Contexts.Num());

	for (int32 Index = 0; Index < NumContexts; ++Index)
	{
		FDynamicMeshElementContext* Context = SceneRenderer.Allocator.Create<FDynamicMeshElementContext>(SceneRenderer);
		Contexts.Emplace(Context);
		CommandLists.Emplace(Context->RHICmdList);
	}
}

void FDynamicMeshElementContextContainer::MergeContexts(TArray<FDynamicPrimitive, SceneRenderingAllocator>& OutDynamicPrimitives)
{
	SCOPED_NAMED_EVENT(MergeGatherDynamicMeshElementContexts, FColor::Magenta);

	check(!Views.IsEmpty());

	// Fast path for one context; just move the memory instead of copying.
	if (Contexts.Num() == 1)
	{
		FDynamicMeshElementContext* Context = Contexts[0];
		OutDynamicPrimitives = MoveTemp(Context->DynamicPrimitives);

		for (int32 ViewIndex = 0; ViewIndex < Views.Num(); ++ViewIndex)
		{
			FViewInfo& View = *Views[ViewIndex];
			FDynamicMeshElementContext::FViewMeshArrays& ViewMeshArrays = Context->ViewMeshArraysPerView[ViewIndex];

			View.SimpleElementCollector = MoveTemp(ViewMeshArrays.SimpleElementCollector);
			View.DynamicMeshElements    = MoveTemp(ViewMeshArrays.DynamicMeshElements);

#if WITH_EDITOR
			View.EditorSimpleElementCollector = MoveTemp(ViewMeshArrays.EditorSimpleElementCollector);
			View.DynamicEditorMeshElements    = MoveTemp(ViewMeshArrays.DynamicEditorMeshElements);
#endif

#if UE_ENABLE_DEBUG_DRAWING
			View.DebugSimpleElementCollector = MoveTemp(ViewMeshArrays.DebugSimpleElementCollector);
#endif
		}
	}
	// >1 context means we have to merge the containers.
	else
	{
		struct FViewAllocationInfo
		{
			FSimpleElementCollector::FAllocationInfo SimpleElementCollector;
			uint32 NumDynamicMeshElements = 0;
#if WITH_EDITOR
			FSimpleElementCollector::FAllocationInfo EditorSimpleElementCollector;
			uint32 NumDynamicEditorMeshElements = 0;
#endif
#if UE_ENABLE_DEBUG_DRAWING
			FSimpleElementCollector::FAllocationInfo DebugSimpleElementCollector;
#endif
		};

		TArray<FViewAllocationInfo, TInlineAllocator<2>> AllocationInfosPerView;
		AllocationInfosPerView.AddDefaulted(Views.Num());
		uint32 NumDynamicPrimitives = 0;

		for (FDynamicMeshElementContext* Context : Contexts)
		{
			NumDynamicPrimitives += Context->DynamicPrimitives.Num();
			check(AllocationInfosPerView.Num() == Context->ViewMeshArraysPerView.Num());

			// Accumulate allocation info for each context in order to reserve container memory once.
			for (int32 ViewIndex = 0; ViewIndex < AllocationInfosPerView.Num(); ++ViewIndex)
			{
				const FDynamicMeshElementContext::FViewMeshArrays& ViewMeshArrays = Context->ViewMeshArraysPerView[ViewIndex];
				FViewAllocationInfo& AllocationInfo = AllocationInfosPerView[ViewIndex];

				ViewMeshArrays.SimpleElementCollector.AddAllocationInfo(AllocationInfo.SimpleElementCollector);
				AllocationInfo.NumDynamicMeshElements += ViewMeshArrays.DynamicMeshElements.Num();
#if WITH_EDITOR
				ViewMeshArrays.EditorSimpleElementCollector.AddAllocationInfo(AllocationInfo.EditorSimpleElementCollector);
				AllocationInfo.NumDynamicEditorMeshElements += ViewMeshArrays.DynamicEditorMeshElements.Num();
#endif
#if UE_ENABLE_DEBUG_DRAWING
				ViewMeshArrays.DebugSimpleElementCollector.AddAllocationInfo(AllocationInfo.DebugSimpleElementCollector);
#endif
			}
		}

		OutDynamicPrimitives.Reserve(NumDynamicPrimitives);

		// Reserve memory for merged containers.
		for (int32 ViewIndex = 0; ViewIndex < Views.Num(); ++ViewIndex)
		{
			FViewAllocationInfo& AllocationInfo = AllocationInfosPerView[ViewIndex];
			FViewInfo& View = *Views[ViewIndex];

			View.SimpleElementCollector.Reserve(AllocationInfo.SimpleElementCollector);
			View.DynamicMeshElements.Reserve(AllocationInfo.NumDynamicMeshElements);
#if WITH_EDITOR
			View.EditorSimpleElementCollector.Reserve(AllocationInfo.EditorSimpleElementCollector);
			View.DynamicEditorMeshElements.Reserve(AllocationInfo.NumDynamicEditorMeshElements);
#endif
#if UE_ENABLE_DEBUG_DRAWING
			View.DebugSimpleElementCollector.Reserve(AllocationInfo.DebugSimpleElementCollector);
#endif

			// Reset dynamic element count to use as offset for copying ranges in the next loop.
			AllocationInfo.NumDynamicMeshElements = 0;
		}

		for (FDynamicMeshElementContext* Context : Contexts)
		{
			for (FDynamicPrimitive DynamicPrimitive : Context->DynamicPrimitives)
			{
				const uint32 NumDynamicMeshElements = AllocationInfosPerView[DynamicPrimitive.ViewIndex].NumDynamicMeshElements;

				// Offset the dynamic element range by the current number of meshes in the final container.
				DynamicPrimitive.StartElementIndex += NumDynamicMeshElements;
				DynamicPrimitive.EndElementIndex   += NumDynamicMeshElements;

				OutDynamicPrimitives.Emplace(DynamicPrimitive);

				Views[DynamicPrimitive.ViewIndex]->DynamicMeshElementRanges[DynamicPrimitive.PrimitiveIndex] = FInt32Vector2(DynamicPrimitive.StartElementIndex, DynamicPrimitive.EndElementIndex);
			}

			for (int32 ViewIndex = 0; ViewIndex < Views.Num(); ++ViewIndex)
			{
				FViewInfo& View = *Views[ViewIndex];
				FDynamicMeshElementContext::FViewMeshArrays& ViewMeshArrays = Context->ViewMeshArraysPerView[ViewIndex];

				AllocationInfosPerView[ViewIndex].NumDynamicMeshElements += ViewMeshArrays.DynamicMeshElements.Num();

				View.SimpleElementCollector.Append(ViewMeshArrays.SimpleElementCollector);
				View.DynamicMeshElements.Append(ViewMeshArrays.DynamicMeshElements);
#if WITH_EDITOR
				View.EditorSimpleElementCollector.Append(ViewMeshArrays.EditorSimpleElementCollector);
				View.DynamicEditorMeshElements.Append(ViewMeshArrays.DynamicEditorMeshElements);
#endif
#if UE_ENABLE_DEBUG_DRAWING
				View.DebugSimpleElementCollector.Append(ViewMeshArrays.DebugSimpleElementCollector);
#endif
			}

			Context->DynamicPrimitives.Empty();
			Context->ViewMeshArraysPerView.Empty();
		}
	}
}

void FDynamicMeshElementContextContainer::Submit(FRHICommandListImmediate& RHICmdList)
{
	for (FDynamicMeshElementContext* Context : Contexts)
	{
		Context->Finish();
	}

	RHICmdList.QueueAsyncCommandListSubmit(CommandLists);
	CommandLists.Empty();
}

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

FVisibilityTaskData::FVisibilityTaskData(FRHICommandListImmediate& InRHICmdList, FSceneRenderer& InSceneRenderer)
	: RHICmdList(InRHICmdList)
	, SceneRenderer(InSceneRenderer)
	, Scene(*SceneRenderer.Scene)
	, Views(SceneRenderer.AllViews)
	, ViewFamily(SceneRenderer.ViewFamily)
	, ShadingPath(GetFeatureLevelShadingPath(Scene.GetFeatureLevel()))
	, TaskConfig(Scene, Views)
	, bAddNaniteRelevance(InSceneRenderer.ShouldRenderNanite())
	, bAddLightmapDensityCommands(ViewFamily.EngineShowFlags.LightMapDensity&& AllowDebugViewmodes())
{
	Tasks.bWaitingAllowed = TaskConfig.Schedule == EVisibilityTaskSchedule::Parallel;
}

void FVisibilityTaskData::LaunchVisibilityTasks(const UE::Tasks::FTask& BeginInitVisibilityPrerequisites)
{
	SCOPED_NAMED_EVENT(LaunchVisibilityTasks, FColor::Magenta);
	ViewPackets.Reserve(Views.Num());

	for (int32 ViewIndex = 0; ViewIndex < Views.Num(); ++ViewIndex)
	{
		if (Views[ViewIndex]->bIsSinglePassStereo && Views[ViewIndex]->StereoPass == EStereoscopicPass::eSSP_SECONDARY)
		{
			continue;
		}

		// Each non-vestigial view gets its own visibility task packet which contains all the state to manage the task graph for a view.
		FVisibilityViewPacket& ViewPacket = ViewPackets.Emplace_GetRef(*this, Scene, *Views[ViewIndex], ViewIndex);

		// Each respective stage of visibility for each view is connected to its corresponding task event in order to track when all views complete each stage.
		Tasks.LightVisibility.AddPrerequisites(ViewPacket.Tasks.LightVisibility);
		Tasks.FrustumCull.AddPrerequisites(ViewPacket.Tasks.FrustumCull);
		Tasks.OcclusionCull.AddPrerequisites(ViewPacket.Tasks.OcclusionCull);
		Tasks.ComputeRelevance.AddPrerequisites(ViewPacket.Tasks.ComputeRelevance);

		if (ViewPacket.ViewState)
		{
			SCOPE_CYCLE_COUNTER(STAT_DecompressPrecomputedOcclusion);
			ViewPacket.View.PrecomputedVisibilityData = ViewPacket.ViewState->ResolvePrecomputedVisibilityData(ViewPacket.View, &Scene);

			if (ViewPacket.View.PrecomputedVisibilityData)
			{
				SceneRenderer.bUsedPrecomputedVisibility = true;
			}
		}
	}

	// Each relevance task should have this as a prerequisite, but in case there aren't any tasks we make it explicit.
	Tasks.ComputeRelevance.AddPrerequisites(Scene.GetCacheMeshDrawCommandsTask());

	// Wait on the GPU skin update task prior to GDME.
	Tasks.DynamicMeshElementsPrerequisites.AddPrerequisites(Scene.GetGPUSkinUpdateTask());

	bool bAllocatePrimitiveViewMasks = true;

	if (TaskConfig.Schedule == EVisibilityTaskSchedule::Parallel)
	{
		if (ViewPackets.Num() == 1)
		{
			// When using a single view, dynamic mesh elements are pushed into a pipe that is executed on the render thread which allows for some overlap with compute relevance work.
			DynamicMeshElements.CommandPipe = Allocator.Create<TCommandPipe<FDynamicPrimitiveIndexList>>(TEXT("GatherDynamicMeshElements"));

			DynamicMeshElements.CommandPipe->SetCommandFunction([this](FDynamicPrimitiveIndexList&& DynamicPrimitiveIndexList)
			{
				GatherDynamicMeshElements(MoveTemp(DynamicPrimitiveIndexList));
			});

			DynamicMeshElements.CommandPipe->SetPrerequisiteTask(Tasks.DynamicMeshElementsPrerequisites);

			Tasks.DynamicMeshElementsPipe = FGraphEvent::CreateGraphEvent();

			DynamicMeshElements.CommandPipe->SetEmptyFunction([this]
			{
				Tasks.DynamicMeshElementsPipe->DispatchSubsequents();
				Tasks.DynamicMeshElements.Trigger();
			});

			// Take a reference that is released when the relevance pipe has completed. We only need to take one since there can only be one view.
			DynamicMeshElements.CommandPipe->AddNumCommands(1);

			// We don't need the primitive view masks when in parallel mode with a single view.
			bAllocatePrimitiveViewMasks = false;
		}
	}

	if (bAllocatePrimitiveViewMasks)
	{
		DynamicMeshElements.PrimitiveViewMasks = Allocator.Create<FDynamicPrimitiveViewMasks>();
		DynamicMeshElements.PrimitiveViewMasks->Primitives.AddZeroed(Scene.Primitives.Num());

	#if WITH_EDITOR
		if (GIsEditor)
		{
			DynamicMeshElements.PrimitiveViewMasks->EditorPrimitives.AddZeroed(Scene.Primitives.Num());
		}
	#endif
	}

	DynamicMeshElements.ContextContainer.Init(SceneRenderer, GetNumDynamicMeshElementTasks());
	DynamicMeshElements.ViewCommandsPerView.SetNum(Views.Num());

	Tasks.LightVisibility.AddPrerequisites(UE::Tasks::Launch(UE_SOURCE_LOCATION, [this]
	{
		FTaskTagScope Scope(ETaskTag::EParallelRenderingThread);
		SceneRenderer.ComputeLightVisibility();

	}, TaskConfig.TaskPriority));

	if (TaskConfig.Schedule == EVisibilityTaskSchedule::Parallel)
	{
		SceneRenderer.WaitOcclusionTests(RHICmdList);

		// Parallel occlusion culling is not supported on mobile
		check(!Views.IsEmpty())
		checkf(!Views[0]->bIsMobileMultiViewEnabled, TEXT("This culling path was not tested with MMV"));

		for (FVisibilityViewPacket& ViewPacket : ViewPackets)
		{
			if (ViewPacket.OcclusionCull.ContextIfParallel)
			{
				ViewPacket.OcclusionCull.ContextIfParallel->Map(RHICmdList);
			}

			Tasks.BeginInitVisibility.AddPrerequisites(UE::Tasks::Launch(UE_SOURCE_LOCATION, [&ViewPacket]
			{
				FTaskTagScope Scope(ETaskTag::EParallelRenderingThread);
				ViewPacket.BeginInitVisibility();

			}, BeginInitVisibilityPrerequisites, TaskConfig.TaskPriority));
		}

		// Static relevance is finalized for ALL views after each view completes static mesh filtering tasks.
		Tasks.FinalizeRelevance = UE::Tasks::Launch(UE_SOURCE_LOCATION, [this]
		{
			TRACE_CPUPROFILER_EVENT_SCOPE(FSceneRenderer_FinalizeStaticRelevance);

			for (FVisibilityViewPacket& ViewPacket : ViewPackets)
			{
				ViewPacket.Relevance.Context->Finalize();
			}

		}, Tasks.ComputeRelevance, TaskConfig.TaskPriority);
	}

	// All task events are connected to prerequisites now and can be safely triggered.
	Tasks.BeginInitVisibility.Trigger();
	Tasks.LightVisibility.Trigger();
	Tasks.FrustumCull.Trigger();
	Tasks.OcclusionCull.Trigger();
	Tasks.ComputeRelevance.Trigger();
}

void FVisibilityTaskData::GatherDynamicMeshElements(FDynamicPrimitiveIndexList&& DynamicPrimitiveIndexList)
{
	FDynamicPrimitiveIndexList RenderThreadDynamicPrimitiveIndexList;

	const int32 NumAsyncContexts = DynamicMeshElements.ContextContainer.GetNumAsyncContexts();

	if (NumAsyncContexts > 0)
	{
		const auto FilterDynamicPrimitives = [] (TArrayView<FPrimitiveSceneProxy*> PrimitiveSceneProxies, FDynamicPrimitiveIndexList::FList& Primitives, FDynamicPrimitiveIndexList::FList& RenderThreadPrimitives)
		{
			for (int32 Index = 0; Index < Primitives.Num(); )
			{
				const FDynamicPrimitiveIndex PrimitiveIndex = Primitives[Index];

				if (!PrimitiveSceneProxies[PrimitiveIndex.Index]->SupportsParallelGDME())
				{
					RenderThreadPrimitives.Emplace(PrimitiveIndex);
					Primitives.RemoveAtSwap(Index, EAllowShrinking::No);
				}
				else
				{
					Index++;
				}
			}
		};

		FilterDynamicPrimitives(Scene.PrimitiveSceneProxies, DynamicPrimitiveIndexList.Primitives, RenderThreadDynamicPrimitiveIndexList.Primitives);
#if WITH_EDITOR
		FilterDynamicPrimitives(Scene.PrimitiveSceneProxies, DynamicPrimitiveIndexList.EditorPrimitives, RenderThreadDynamicPrimitiveIndexList.EditorPrimitives);
#endif
	}
	else
	{
		RenderThreadDynamicPrimitiveIndexList = MoveTemp(DynamicPrimitiveIndexList);
		DynamicPrimitiveIndexList = {};
	}

	if (!RenderThreadDynamicPrimitiveIndexList.IsEmpty())
	{
		Tasks.DynamicMeshElementsRenderThread = DynamicMeshElements.ContextContainer.LaunchRenderThreadTask(MoveTemp(RenderThreadDynamicPrimitiveIndexList));
	}

	if (!DynamicPrimitiveIndexList.IsEmpty())
	{
		FDynamicPrimitiveIndexQueue* Queue = Allocator.Create<FDynamicPrimitiveIndexQueue>(MoveTemp(DynamicPrimitiveIndexList));

		for (int32 Index = 0; Index < DynamicMeshElements.ContextContainer.GetNumAsyncContexts(); ++Index)
		{
			Tasks.DynamicMeshElements.AddPrerequisites(DynamicMeshElements.ContextContainer.LaunchAsyncTask(Queue, Index, TaskConfig.TaskPriority));
		}
	}
}

void FVisibilityTaskData::GatherDynamicMeshElements(const FDynamicPrimitiveViewMasks& DynamicPrimitiveViewMasks)
{
	SCOPED_NAMED_EVENT(GatherDynamicMeshElements, FColor::Magenta);

	Tasks.DynamicMeshElementsPrerequisites.Wait();

	const auto GetPrimaryViewMask = [this] (uint8 ViewMask) -> uint8
	{
		// If a mesh is visible in a secondary view, mark it as visible in the primary view
		uint8 ViewMaskFinal = ViewMask;

		for (int32 ViewIndex = 0; ViewIndex < Views.Num(); ViewIndex++)
		{
			const FViewInfo& View = *Views[ViewIndex];

			if (ViewMask & (1 << ViewIndex) && IStereoRendering::IsASecondaryView(View))
			{
				ViewMaskFinal |= 1 << Views[ViewIndex]->PrimaryViewIndex;
			}
		}

		return ViewMaskFinal;
	};

	FDynamicPrimitiveIndexList DynamicPrimitiveIndexList;
	DynamicPrimitiveIndexList.Primitives.Reserve(128);

	const int32 NumPrimitives = DynamicPrimitiveViewMasks.Primitives.Num();

	for (int32 PrimitiveIndex = 0; PrimitiveIndex < NumPrimitives; ++PrimitiveIndex)
	{
		const uint8 ViewMask = DynamicPrimitiveViewMasks.Primitives[PrimitiveIndex];

		if (ViewMask != 0)
		{
			DynamicPrimitiveIndexList.Primitives.Emplace(PrimitiveIndex, GetPrimaryViewMask(ViewMask));
		}
	}

#if WITH_EDITOR
	if (GIsEditor)
	{
		DynamicPrimitiveIndexList.EditorPrimitives.Reserve(128);

		for (int32 PrimitiveIndex = 0; PrimitiveIndex < NumPrimitives; ++PrimitiveIndex)
		{
			const uint8 ViewMask = DynamicPrimitiveViewMasks.EditorPrimitives[PrimitiveIndex];

			if (ViewMask != 0)
			{
				DynamicPrimitiveIndexList.EditorPrimitives.Emplace(PrimitiveIndex, GetPrimaryViewMask(ViewMask));
			}
		}
	}
#endif

	GatherDynamicMeshElements(MoveTemp(DynamicPrimitiveIndexList));
	Tasks.DynamicMeshElements.Trigger();
}

void FVisibilityTaskData::SetupMeshPasses(FExclusiveDepthStencil::Type BasePassDepthStencilAccess, FInstanceCullingManager& InstanceCullingManager)
{
	DynamicMeshElements.ContextContainer.MergeContexts(DynamicMeshElements.DynamicPrimitives);

	{
		SCOPED_NAMED_EVENT(DynamicRelevance, FColor::Magenta);

		for (FViewInfo* View : Views)
		{
			View->DynamicMeshElementsPassRelevance.SetNum(View->DynamicMeshElements.Num());
		}

		const bool bIsTLVUsingVoxelMarking = IsTranslucencyLightingVolumeUsingVoxelMarking();

		for (FDynamicPrimitive DynamicPrimitive : DynamicMeshElements.DynamicPrimitives)
		{
			FPrimitiveSceneInfo* PrimitiveSceneInfo = Scene.Primitives[DynamicPrimitive.PrimitiveIndex];
			const FPrimitiveBounds& Bounds = Scene.PrimitiveBounds[DynamicPrimitive.PrimitiveIndex];
			FViewInfo& View = *Views[DynamicPrimitive.ViewIndex];
			const FPrimitiveViewRelevance& ViewRelevance = View.PrimitiveViewRelevanceMap[DynamicPrimitive.PrimitiveIndex];

			for (int32 ElementIndex = DynamicPrimitive.StartElementIndex; ElementIndex < DynamicPrimitive.EndElementIndex; ++ElementIndex)
			{
				const FMeshBatchAndRelevance& MeshBatch = View.DynamicMeshElements[ElementIndex];
				FMeshPassMask& PassRelevance = View.DynamicMeshElementsPassRelevance[ElementIndex];

				ComputeDynamicMeshRelevance(ShadingPath, bAddLightmapDensityCommands, bIsTLVUsingVoxelMarking, ViewRelevance, MeshBatch, View, PassRelevance, PrimitiveSceneInfo, Bounds);
			}
		}
	}

	for (int32 ViewIndex = 0; ViewIndex < Views.Num(); ViewIndex++)
	{
		FViewInfo& View = *Views[ViewIndex];

	#if WITH_EDITOR
		{
			// Sort the selected Nanite hit proxy IDs
			Algo::Sort(View.EditorSelectedNaniteHitProxyIds);

			// Make sure it is power of 2 as it is searched in the shader with binary search that only works with power2 buffer sizes
			int32 PreviousCount = View.EditorSelectedNaniteHitProxyIds.Num();
			int32 NewCount = FMath::RoundUpToPowerOfTwo(PreviousCount);
			
			if (PreviousCount > 0)
			{
				const uint32 LastValue = View.EditorSelectedNaniteHitProxyIds.Last();
				View.EditorSelectedNaniteHitProxyIds.SetNumUninitialized(NewCount);
				// Pad the end with the last value to ensure still sorted
				for (int32 Index = PreviousCount; Index < NewCount; ++Index)
				{
					View.EditorSelectedNaniteHitProxyIds[Index] = LastValue;
				}
			}
		}
	#endif

	#if !(UE_BUILD_SHIPPING || UE_BUILD_TEST)
		FSceneViewState* ViewState = static_cast<FSceneViewState*>(View.State);

		// if we are freezing the scene, then remember the primitives that are rendered.
		if (ViewState && ViewState->bIsFreezing)
		{
			for (FSceneSetBitIterator BitIt(View.PrimitiveVisibilityMap); BitIt; ++BitIt)
			{
				ViewState->FrozenPrimitives.Add(Scene.PrimitiveComponentIds[BitIt.GetIndex()]);
			}
		}
	#endif

		if (!View.ShouldRenderView())
		{
			continue;
		}

		FViewCommands& ViewCommands = DynamicMeshElements.ViewCommandsPerView[ViewIndex];

	#if !UE_BUILD_SHIPPING
		FViewDebugInfo::Get().ProcessPrimitives(&Scene, View, ViewCommands);
	#endif

		SceneRenderer.SetupMeshPass(View, BasePassDepthStencilAccess, ViewCommands, InstanceCullingManager);
	}
}

void FVisibilityTaskData::ProcessRenderThreadTasks()
{
	SCOPE_CYCLE_COUNTER(STAT_ViewVisibilityTime);
	SCOPED_NAMED_EVENT(ProcessVisibilityTasks, FColor::Magenta);

	UE::Tasks::FTask VirtualTextureTask;

	StartGatherDynamicMeshElements();

	FPrimitiveRange PrimitiveRange;
	PrimitiveRange.StartIndex = 0u;
	PrimitiveRange.EndIndex = TaskConfig.NumTestedPrimitives;

	if (TaskConfig.Schedule == EVisibilityTaskSchedule::RenderThread)
	{
		for (FVisibilityViewPacket& ViewPacket : ViewPackets)
		{
			ViewPacket.BeginInitVisibility();
			UpdatePrimitiveFading(Scene, ViewPacket.View, ViewPacket.ViewState, PrimitiveRange);
		}

		SceneRenderer.WaitOcclusionTests(RHICmdList);

		for (FVisibilityViewPacket& ViewPacket : ViewPackets)
		{
			SCOPED_NAMED_EVENT(OcclusionCull, FColor::Magenta);
			const int32 NumCulledPrimitives = PrecomputedOcclusionCull(ViewPacket, PrimitiveRange);

			if (ViewPacket.OcclusionCull.ContextIfSerial)
			{
				ViewPacket.OcclusionCull.ContextIfSerial->Map(RHICmdList);
				ViewPacket.OcclusionCull.ContextIfSerial->AddPrimitives(PrimitiveRange);
				ViewPacket.OcclusionCull.ContextIfSerial->Unmap(RHICmdList);
			}

			if (NumCulledPrimitives > 0)
			{
				TaskConfig.OcclusionCull.NumCulledPrimitives.fetch_add(NumCulledPrimitives, std::memory_order_relaxed);
			}

			ViewPacket.Tasks.OcclusionCull.Trigger();
		}

		// Relevance requires that cached mesh commands be available first.
		Scene.WaitForCacheMeshDrawCommandsTask();

		for (FVisibilityViewPacket& ViewPacket : ViewPackets)
		{
			for (FSceneSetBitIterator BitIt(ViewPacket.View.PrimitiveVisibilityMap, PrimitiveRange.StartIndex); BitIt.GetIndex() < PrimitiveRange.EndIndex; ++BitIt)
			{
				ViewPacket.Relevance.Context->AddPrimitive(BitIt.GetIndex());
			}
			ViewPacket.Relevance.Context->Finalize();
			ViewPacket.Tasks.ComputeRelevance.Trigger();
		}

		Tasks.bWaitingAllowed = true;

		check(DynamicMeshElements.PrimitiveViewMasks);
		GatherDynamicMeshElements(*DynamicMeshElements.PrimitiveViewMasks);
	}
	else
	{
		if (DynamicMeshElements.CommandPipe)
		{
			SCOPED_NAMED_EVENT(WaitForVisibilityTasks, FColor::Magenta);
			CSV_SCOPED_SET_WAIT_STAT(Visibility);

			// Wait on the command pipe first as it will be continually updating the render thread event (and process tasks while we wait).
			Tasks.DynamicMeshElementsPipe->Wait(ENamedThreads::GetRenderThread_Local());
		}
		else
		{
			Tasks.ComputeRelevance.Wait();
			check(DynamicMeshElements.PrimitiveViewMasks);
			GatherDynamicMeshElements(*DynamicMeshElements.PrimitiveViewMasks);
		}

		for (FVisibilityViewPacket& ViewPacket : ViewPackets)
		{
			if (ViewPacket.OcclusionCull.ContextIfParallel)
			{
				ViewPacket.OcclusionCull.ContextIfParallel->Unmap(RHICmdList);
			}
		}
	}

	// Now process all gather dynamic mesh element tasks that were queued up to run on the render thread.
	if (Tasks.DynamicMeshElementsRenderThread)
	{
		Tasks.DynamicMeshElementsRenderThread->Wait(ENamedThreads::GetRenderThread_Local());
	}

	Tasks.LightVisibility.Wait();
	Tasks.FinalizeRelevance.Wait();

	INC_DWORD_STAT_BY(STAT_ProcessedPrimitives, PrimitiveRange.EndIndex * Views.Num());
	INC_DWORD_STAT_BY(STAT_CulledPrimitives, TaskConfig.FrustumCull.NumCulledPrimitives);
	INC_DWORD_STAT_BY(STAT_OccludedPrimitives, TaskConfig.OcclusionCull.NumCulledPrimitives);

	TRACE_COUNTER_SET(Scene_Visibility_NumProcessedPrimitives, PrimitiveRange.EndIndex * Views.Num());
	TRACE_COUNTER_SET(Scene_Visibility_FrustumCull_NumPrimitivesPerTask, TaskConfig.FrustumCull.NumPrimitivesPerTask);
	TRACE_COUNTER_SET(Scene_Visibility_FrustumCull_NumCulledPrimitives, TaskConfig.FrustumCull.NumCulledPrimitives);
	TRACE_COUNTER_SET(Scene_Visibility_OcclusionCull_NumCulledPrimitives, TaskConfig.OcclusionCull.NumCulledPrimitives);
	TRACE_COUNTER_SET(Scene_Visibility_OcclusionCull_NumTestedQueries, TaskConfig.OcclusionCull.NumTestedQueries);
	TRACE_COUNTER_SET(Scene_Visibility_Relevance_NumPrimitivesPerPacket, TaskConfig.Relevance.NumPrimitivesPerPacket);
}

void FVisibilityTaskData::FinishGatherDynamicMeshElements(FExclusiveDepthStencil::Type BasePassDepthStencilAccess, FInstanceCullingManager& InstanceCullingManager, FVirtualTextureUpdater* VirtualTextureUpdater)
{
	check(IsInRenderingThread());
	SCOPED_NAMED_EVENT(FinishDynamicMeshElements, FColor::Magenta);

	FVirtualTextureSystem::Get().WaitForTasks(VirtualTextureUpdater);
	Tasks.DynamicMeshElements.Wait();
	DynamicMeshElements.ContextContainer.Submit(RHICmdList);

	Tasks.MeshPassSetup = UE::Tasks::Launch(UE_SOURCE_LOCATION, [this, BasePassDepthStencilAccess, &InstanceCullingManager]
	{
		FTaskTagScope Scope(ETaskTag::EParallelRenderingThread);
		SetupMeshPasses(BasePassDepthStencilAccess, InstanceCullingManager);

	}, TaskConfig.TaskPriority);

	FSceneRenderer::DynamicReadBufferForInitViews.Commit(RHICmdList);
}

void FVisibilityTaskData::Finish()
{
	SCOPED_NAMED_EVENT(FinishVisibility, FColor::Magenta);

	Tasks.ComputeRelevance.Wait();
	Tasks.FinalizeRelevance.Wait();
	Tasks.DynamicMeshElements.Wait();
	Tasks.MeshPassSetup.Wait();

	ViewPackets.Empty();
	DynamicMeshElements.DynamicPrimitives.Empty();
	Allocator.BulkDelete();
	bFinished = true;
}

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

/**
 * Helper for InitViews to detect large camera movement, in both angle and position.
 */
static bool IsLargeCameraMovement(FSceneView& View, const FMatrix& PrevViewMatrix, const FVector& PrevViewOrigin, float CameraRotationThreshold, float CameraTranslationThreshold)
{
	float RotationThreshold = FMath::Cos(FMath::DegreesToRadians(CameraRotationThreshold));
	float ViewRightAngle = View.ViewMatrices.GetViewMatrix().GetColumn(0) | PrevViewMatrix.GetColumn(0);
	float ViewUpAngle = View.ViewMatrices.GetViewMatrix().GetColumn(1) | PrevViewMatrix.GetColumn(1);
	float ViewDirectionAngle = View.ViewMatrices.GetViewMatrix().GetColumn(2) | PrevViewMatrix.GetColumn(2);

	FVector Distance = FVector(View.ViewMatrices.GetViewOrigin()) - PrevViewOrigin;
	return 
		ViewRightAngle < RotationThreshold ||
		ViewUpAngle < RotationThreshold ||
		ViewDirectionAngle < RotationThreshold ||
		Distance.SizeSquared() > CameraTranslationThreshold * CameraTranslationThreshold;
}

void FSceneRenderer::PreVisibilityFrameSetup(FRDGBuilder& GraphBuilder)
{
	FRHICommandListImmediate& RHICmdList = GraphBuilder.RHICmdList;
	
	if (GetRendererOutput() == ERendererOutput::FinalSceneColor)
	{
		FHairStrandsBookmarkParameters Parameters;
        bool bHasHairStrandsBookmarks = false;
		
		if (Views.Num() > 0 && !ViewFamily.EngineShowFlags.HitProxies)
		{
			CreateHairStrandsBookmarkParameters(Scene, Views, AllViews, Parameters, false /*bComputeVisibleInstances*/);
			Parameters.TransientResources = AllocateHairTransientResources(GraphBuilder, Scene, Views);
			if (Parameters.HasInstances())
			{
				if (Scene && IsHairStrandsEnabled(EHairStrandsShaderType::All, Scene->GetShaderPlatform()))
				{
					// Need GPUSkinCache results to be available in order to get correct skel. mesh data
					Scene->GetGPUSkinCacheTask().Wait();

					// 1.Update binding surfaces
					// Prepare surface data (MeshLODData)
					RunHairStrandsBookmark(GraphBuilder, EHairStrandsBookmark::ProcessBindingSurfaceUpdate, Parameters);

					// 2. Prepare surface data for guides
					if (Views[0].AllowGPUParticleUpdate())
					{
						RunHairStrandsBookmark(GraphBuilder, EHairStrandsBookmark::ProcessGuideInterpolation, Parameters);
						bHasHairStrandsBookmarks = true;
					}
				}
			}
		}

		if(Scene)
		{
			for (IComputeTaskWorker* ComputeTaskWorker : Scene->ComputeTaskWorkers)
			{
				if (ComputeTaskWorker->HasWork(ComputeTaskExecutionGroup::BeginInitViews))
				{
					ComputeTaskWorker->SubmitWork(GraphBuilder, ComputeTaskExecutionGroup::BeginInitViews, FeatureLevel);
				}
			}
		}

		// Notify the FX system that the scene is about to perform visibility checks.

		if (FXSystem && Views.IsValidIndex(0))
		{
			TArray<const FSceneViewFamily*, TInlineAllocator<2>> AllLinkedFamilies;
			EnumerateLinkedViewFamilies([&] (const FSceneViewFamily& Family)
			{
				AllLinkedFamilies.Emplace(&Family);
				return true;
			});
			FXSystem->PreInitViews(GraphBuilder, Views[0].AllowGPUParticleUpdate() && !ViewFamily.EngineShowFlags.HitProxies, AllLinkedFamilies, &ViewFamily);
		}

		if(bHasHairStrandsBookmarks)
		{
			RunHairStrandsBookmark(GraphBuilder, EHairStrandsBookmark::ProcessGuideDeformation, Parameters);
		}

#if WITH_EDITOR
		// Draw lines to lights affecting this mesh if its selected.
		if (ViewFamily.EngineShowFlags.LightInfluences && Scene)
		{
			Scene->WaitForCreateLightPrimitiveInteractionsTask();

			for (TConstSetBitIterator<> It(Scene->PrimitivesSelected); It; ++It)
			{
				const FPrimitiveSceneInfo* PrimitiveSceneInfo = Scene->Primitives[It.GetIndex()];

				TArray<const FLightSceneProxy*> RelevantLights;
				Scene->GetRelevantLights_RenderThread(PrimitiveSceneInfo->Proxy, RelevantLights);

				for (const FLightSceneProxy* LightSceneProxy : RelevantLights)
				{
					bool bDynamic = true;
					bool bRelevant = false;
					bool bLightMapped = true;
					bool bShadowMapped = false;
					PrimitiveSceneInfo->Proxy->GetLightRelevance(LightSceneProxy, bDynamic, bRelevant, bLightMapped, bShadowMapped);

					if (bRelevant)
					{
						// Draw blue for light-mapped lights and orange for dynamic lights
						const FColor LineColor = bLightMapped ? FColor(0, 140, 255) : FColor(255, 140, 0);
						for (int32 ViewIndex = 0; ViewIndex < Views.Num(); ViewIndex++)
						{
							FViewInfo& View = Views[ViewIndex];
							FViewElementPDI LightInfluencesPDI(&View, nullptr, &View.DynamicPrimitiveCollector);
							LightInfluencesPDI.DrawLine(PrimitiveSceneInfo->Proxy->GetBounds().Origin, LightSceneProxy->GetLightToWorld().GetOrigin(), LineColor, SDPG_World);
						}
					}
				}
			}
		}
#endif

#if RHI_RAYTRACING
		if (Scene && Views.Num())
		{
			const int32 ReferenceViewIndex = 0;
			const FViewInfo& ReferenceView = Views[ReferenceViewIndex];

			Scene->RayTracingScene.InitPreViewTranslation(ReferenceView.ViewMatrices);
			Scene->RayTracingScene.bNeedsInstanceExtraDataBuffer = IsRayTracingInstanceOverlapEnabled(ReferenceView);
			Scene->RayTracingScene.bTracingFeedbackEnabled = IsRayTracingFeedbackEnabled(ViewFamily);

			for (int32 ViewIndex = 0; ViewIndex < Views.Num(); ViewIndex++)
			{
				FViewInfo& View = Views[ViewIndex];
				View.bRayTracingFeedbackEnabled = Scene->RayTracingScene.bTracingFeedbackEnabled;
			}
		}
#endif
	}

	for (const auto& ViewExtension : ViewFamily.ViewExtensions)
	{
		ViewExtension->PreInitViews_RenderThread(GraphBuilder);
	}
}

void FSceneRenderer::PrepareViewStateForVisibility(const FSceneTexturesConfig& SceneTexturesConfig)
{
	TRACE_CPUPROFILER_EVENT_SCOPE(PrepareViewStateForVisibility);

#if UE_BUILD_SHIPPING
	const bool bFreezeTemporalHistories = false;
	const bool bFreezeTemporalSequences = false;
#else
	bool bFreezeTemporalHistories = CVarFreezeTemporalHistories.GetValueOnRenderThread() != 0;

	static int32 CurrentFreezeTemporalHistoriesProgress = 0;
	if (CurrentFreezeTemporalHistoriesProgress != CVarFreezeTemporalHistoriesProgress.GetValueOnRenderThread())
	{
		bFreezeTemporalHistories = false;
		CurrentFreezeTemporalHistoriesProgress = CVarFreezeTemporalHistoriesProgress.GetValueOnRenderThread();
	}

	bool bFreezeTemporalSequences = bFreezeTemporalHistories || CVarFreezeTemporalSequences.GetValueOnRenderThread() != 0;
#endif

	// Load this field once so it has a consistent value for all views (and to avoid the atomic load in the loop).
	// While the value may not be perfectly in sync when we render other view families, this is ok as this
	// invalidation mechanism is only used for interactive rendering where we expect to be constantly drawing the scene.
	// Therefore it is acceptable for some view families to be a frame or so behind others.
	uint32 CurrentPathTracingInvalidationCounter = Scene->PathTracingInvalidationCounter.Load();

	// Setup motion blur parameters (also check for camera movement thresholds)
	for(int32 ViewIndex = 0;ViewIndex < AllViews.Num();ViewIndex++)
	{
		FViewInfo& View = *AllViews[ViewIndex];
		FSceneViewState* ViewState = View.ViewState;

#if DO_CHECK || USING_CODE_ANALYSIS
		check(View.VerifyMembersChecks());
#endif

		// Setup global dither fade in and fade out uniform buffers.
		{
			FDitherUniformShaderParameters DitherUniformShaderParameters;
			DitherUniformShaderParameters.LODFactor = View.GetTemporalLODTransition();
			View.DitherFadeOutUniformBuffer = FDitherUniformBufferRef::CreateUniformBufferImmediate(DitherUniformShaderParameters, UniformBuffer_SingleFrame);

			DitherUniformShaderParameters.LODFactor = View.GetTemporalLODTransition() - 1.0f;
			View.DitherFadeInUniformBuffer = FDitherUniformBufferRef::CreateUniformBufferImmediate(DitherUniformShaderParameters, UniformBuffer_SingleFrame);
		}

		// Once per render increment the occlusion frame counter.
		if (ViewState)
		{
			ViewState->OcclusionFrameCounter++;
		}

		// HighResScreenshot should get best results so we don't do the occlusion optimization based on the former frame
		extern bool GIsHighResScreenshot;
		const bool bIsHitTesting = ViewFamily.EngineShowFlags.HitProxies;
		// Don't test occlusion queries in collision viewmode as they can be bigger then the rendering bounds.
		const bool bCollisionView = ViewFamily.EngineShowFlags.CollisionVisibility || ViewFamily.EngineShowFlags.CollisionPawn;
		if (GIsHighResScreenshot || !DoOcclusionQueries() || bIsHitTesting || bCollisionView || ViewFamily.EngineShowFlags.DisableOcclusionQueries)
		{
			View.bDisableQuerySubmissions = true;
			View.bIgnoreExistingQueries = true;
		}

		// set up the screen area for occlusion
		{
			float OcclusionPixelMultiplier = 1.0f;
			if (UseDownsampledOcclusionQueries())
			{
				OcclusionPixelMultiplier = 1.0f / static_cast<float>(FMath::Square(SceneTexturesConfig.SmallDepthDownsampleFactor));
			}
			float NumPossiblePixels = static_cast<float>(View.ViewRect.Width() * View.ViewRect.Height()) * OcclusionPixelMultiplier;
			View.OneOverNumPossiblePixels = NumPossiblePixels > 0.0 ? 1.0f / NumPossiblePixels : 0.0f;
		}

		// Still need no jitter to be set for temporal feedback on SSR (it is enabled even when temporal AA is off).
		check(View.TemporalJitterPixels.X == 0.0f);
		check(View.TemporalJitterPixels.Y == 0.0f);
		
		// Cache the projection matrix b		
		// Cache the projection matrix before AA is applied
		View.ViewMatrices.SaveProjectionNoAAMatrix();

		if (ViewState)
		{
			check(View.bStatePrevViewInfoIsReadOnly);
			View.bStatePrevViewInfoIsReadOnly = ViewFamily.bWorldIsPaused || ViewFamily.EngineShowFlags.HitProxies || bFreezeTemporalHistories;

			ViewState->SetupDistanceFieldTemporalOffset(ViewFamily);

			if (!View.bStatePrevViewInfoIsReadOnly && !bFreezeTemporalSequences)
			{
				ViewState->FrameIndex++;
			}

			if (View.OverrideFrameIndexValue.IsSet())
			{
				ViewState->FrameIndex = View.OverrideFrameIndexValue.GetValue();
			}

			if (View.OverrideOutputFrameIndexValue.IsSet())
			{
				ViewState->OutputFrameIndex = View.OverrideOutputFrameIndexValue.GetValue();
			}
			else
			{
				// If the output frame index isn't being overwritten then we keep it in sync with
				// FrameIndex so that downstream systems are unchanged.
				ViewState->OutputFrameIndex = ViewState->FrameIndex;
			}
		}
		
		// Subpixel jitter for temporal AA
		int32 CVarTemporalAASamplesValue = CVarTemporalAASamples.GetValueOnRenderThread();
		const bool bShouldScaleTemporalAASampleCount = (CVarTemporalAAScaleSamples.GetValueOnRenderThread() != 0);

		// Custom render passes support sharing temporal state with the main view
		FViewInfo& TemporalSourceView = View.TemporalSourceView ? *View.TemporalSourceView : View;
		FSceneViewState* TemporalViewState = TemporalSourceView.ViewState;

		EMainTAAPassConfig TAAConfig = GetMainTAAPassConfig(TemporalSourceView);

		bool bTemporalUpsampling = TemporalSourceView.PrimaryScreenPercentageMethod == EPrimaryScreenPercentageMethod::TemporalUpscale;
		
		// Apply a sub pixel offset to the view.
		if (IsTemporalAccumulationBasedMethod(TemporalSourceView.AntiAliasingMethod) && TemporalViewState && (CVarTemporalAASamplesValue > 0 || bTemporalUpsampling) && TemporalSourceView.bAllowTemporalJitter)
		{
			float EffectivePrimaryResolutionFraction = float(View.ViewRect.Width()) / float(TemporalSourceView.GetSecondaryViewRectSize().X);

			// Compute number of TAA samples.
			int32 TemporalAASamples;
			{
				if (TAAConfig == EMainTAAPassConfig::TSR)
				{
					// Force the number of AA sample to make sure the quality doesn't get
					// compromised by previously set settings for Gen4 TAA
					TemporalAASamples = 8;
				}
				else
				{
					TemporalAASamples = FMath::Clamp(CVarTemporalAASamplesValue, 1, 255);
				}

				if (bTemporalUpsampling && bShouldScaleTemporalAASampleCount)
				{
					// When doing TAA upsample with screen percentage < 100%, we need extra temporal samples to have a
					// constant temporal sample density for final output pixels to avoid output pixel aligned converging issues.
					TemporalAASamples = FMath::RoundToInt(float(TemporalAASamples) * FMath::Max(1.f, 1.f / (EffectivePrimaryResolutionFraction * EffectivePrimaryResolutionFraction)));
				}
				else if (CVarTemporalAASamplesValue == 5)
				{
					TemporalAASamples = 4;
				}

				// Use immediately higher prime number to break up coherence between the TAA jitter sequence and any
				// other random signal that are power of two of View.StateFrameIndex
				if (TAAConfig == EMainTAAPassConfig::TSR)
				{
					static const uint8 kFirstPrimeNumbers[] = {
						2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31, 37, 41, 43, 47, 53, 59, 61, 67, 71, 73, 79, 83, 89, 97,
						101, 103, 107, 109, 113, 127, 131, 137, 139, 149, 151, 157, 163, 167, 173, 179, 181, 191, 193, 197, 199,
						211, 223, 227, 229, 233, 239, 241, 251,
					};

					for (int32 PrimeNumberId = FMath::Max(4, (TemporalAASamples - 1) / 5); PrimeNumberId < UE_ARRAY_COUNT(kFirstPrimeNumbers); PrimeNumberId++)
					{
						if (int32(kFirstPrimeNumbers[PrimeNumberId]) >= TemporalAASamples)
						{
							TemporalAASamples = int32(kFirstPrimeNumbers[PrimeNumberId]);
							break;
						}
					}
				}
			}

			// Compute the new sample index in the temporal sequence.
			int32 TemporalSampleIndex;
			if (View.TemporalSourceView)
			{
				// Where a TemporalSourceView is specified, the temporal sample index is pulled directly from the source view's state, and not incremented,
				// assuming the	source view already will have updated that.
				TemporalSampleIndex = TemporalViewState->TemporalAASampleIndex;
			}
			else
			{
				TemporalSampleIndex = TemporalViewState->TemporalAASampleIndex + 1;
				if (TemporalSampleIndex >= TemporalAASamples || View.bCameraCut)
				{
					TemporalSampleIndex = 0;
				}

				#if !UE_BUILD_SHIPPING
				if (CVarTAADebugOverrideTemporalIndex.GetValueOnRenderThread() >= 0)
				{
					TemporalSampleIndex = CVarTAADebugOverrideTemporalIndex.GetValueOnRenderThread();
				}
				#endif

				// Updates view state.
				if (!View.bStatePrevViewInfoIsReadOnly && !bFreezeTemporalSequences)
				{
					TemporalViewState->TemporalAASampleIndex = TemporalSampleIndex;
				}
			}

			// Choose sub pixel sample coordinate in the temporal sequence.
			float SampleX = 0.0f, SampleY = 0.0f;
			if (TemporalSourceView.PrimaryScreenPercentageMethod == EPrimaryScreenPercentageMethod::TemporalUpscale)
			{
				// Uniformly distribute temporal jittering in [-.5; .5], because there is no longer any alignement of input and output pixels.
				SampleX = Halton(TemporalSampleIndex + 1, 2) - 0.5f;
				SampleY = Halton(TemporalSampleIndex + 1, 3) - 0.5f;

				// Adjust Automatic View Mip Bias
				float MipBias = -(FMath::Max(-FMath::Log2(EffectivePrimaryResolutionFraction), 0.0f)) + CVarAutomaticViewMipBiasOffset.GetValueOnRenderThread();
				MipBias = FMath::Clamp(FMath::Max(MipBias, CVarAutomaticViewMipBiasMin.GetValueOnRenderThread()), -4.0f, 4.0f);

				// Quantize to discrete values between -4.0f and 4.0f (range of 8.0f), since each value creates a unique sampler state
				const int32 MipBiasQuantization = CVarAutomaticViewMipBiasQuantization.GetValueOnRenderThread();

				if (MipBiasQuantization > 0)
				{
					// Divide the 8.0f range by the number of desired steps to get the step size
					const float QuantizationStepSize = 8.0f / ((float)MipBiasQuantization);
					MipBias = FMath::CeilToFloat(MipBias / QuantizationStepSize) * QuantizationStepSize;
				}
				
				View.MaterialTextureMipBias = MipBias;
			}
			else if( CVarTemporalAASamplesValue == 2 )
			{
				// 2xMSAA
				// Pattern docs: http://msdn.microsoft.com/en-us/library/windows/desktop/ff476218(v=vs.85).aspx
				//   N.
				//   .S
				float SamplesX[] = { -4.0f/16.0f, 4.0/16.0f };
				float SamplesY[] = { -4.0f/16.0f, 4.0/16.0f };
				check(TemporalAASamples == UE_ARRAY_COUNT(SamplesX));
				SampleX = SamplesX[ TemporalSampleIndex ];
				SampleY = SamplesY[ TemporalSampleIndex ];
			}
			else if( CVarTemporalAASamplesValue == 3 )
			{
				// 3xMSAA
				//   A..
				//   ..B
				//   .C.
				// Rolling circle pattern (A,B,C).
				float SamplesX[] = { -2.0f/3.0f,  2.0/3.0f,  0.0/3.0f };
				float SamplesY[] = { -2.0f/3.0f,  0.0/3.0f,  2.0/3.0f };
				check(TemporalAASamples == UE_ARRAY_COUNT(SamplesX));
				SampleX = SamplesX[ TemporalSampleIndex ];
				SampleY = SamplesY[ TemporalSampleIndex ];
			}
			else if( CVarTemporalAASamplesValue == 4 )
			{
				// 4xMSAA
				// Pattern docs: http://msdn.microsoft.com/en-us/library/windows/desktop/ff476218(v=vs.85).aspx
				//   .N..
				//   ...E
				//   W...
				//   ..S.
				// Rolling circle pattern (N,E,S,W).
				float SamplesX[] = { -2.0f/16.0f,  6.0/16.0f, 2.0/16.0f, -6.0/16.0f };
				float SamplesY[] = { -6.0f/16.0f, -2.0/16.0f, 6.0/16.0f,  2.0/16.0f };
				check(TemporalAASamples == UE_ARRAY_COUNT(SamplesX));
				SampleX = SamplesX[ TemporalSampleIndex ];
				SampleY = SamplesY[ TemporalSampleIndex ];
			}
			else if( CVarTemporalAASamplesValue == 5 )
			{
				// Compressed 4 sample pattern on same vertical and horizontal line (less temporal flicker).
				// Compressed 1/2 works better than correct 2/3 (reduced temporal flicker).
				//   . N .
				//   W . E
				//   . S .
				// Rolling circle pattern (N,E,S,W).
				float SamplesX[] = {  0.0f/2.0f,  1.0/2.0f,  0.0/2.0f, -1.0/2.0f };
				float SamplesY[] = { -1.0f/2.0f,  0.0/2.0f,  1.0/2.0f,  0.0/2.0f };
				check(TemporalAASamples == UE_ARRAY_COUNT(SamplesX));
				SampleX = SamplesX[ TemporalSampleIndex ];
				SampleY = SamplesY[ TemporalSampleIndex ];
			}
			else if(View.IsPerspectiveProjection())
			{
				float u1 = Halton( TemporalSampleIndex + 1, 2 );
				float u2 = Halton( TemporalSampleIndex + 1, 3 );

				// Generates samples in normal distribution
				// exp( x^2 / Sigma^2 )
					
				static auto CVar = IConsoleManager::Get().FindConsoleVariable(TEXT("r.TemporalAAFilterSize"));
				float FilterSize = CVar->GetFloat();

				// Scale distribution to set non-unit variance
				// Variance = Sigma^2
				float Sigma = 0.47f * FilterSize;

				// Window to [-0.5, 0.5] output
				// Without windowing we could generate samples far away on the infinite tails.
				float OutWindow = 0.5f;
				float InWindow = FMath::Exp( -0.5 * FMath::Square( OutWindow / Sigma ) );
					
				// Box-Muller transform
				float Theta = 2.0f * PI * u2;
				float r = Sigma * FMath::Sqrt( -2.0f * FMath::Loge( (1.0f - u1) * InWindow + u1 ) );
					
				SampleX = r * FMath::Cos( Theta );
				SampleY = r * FMath::Sin( Theta );
			}

			if (CVarInvertTemporalJitterX.GetValueOnRenderThread() != 0)
			{
				SampleX = -SampleX;
			}

			if (CVarInvertTemporalJitterY.GetValueOnRenderThread() != 0)
			{
				SampleY = -SampleY;
			}

			View.TemporalJitterSequenceLength = TemporalAASamples;
			View.TemporalJitterIndex = TemporalSampleIndex;
			View.TemporalJitterPixels.X = SampleX;
			View.TemporalJitterPixels.Y = SampleY;

			View.ViewMatrices.HackAddTemporalAAProjectionJitter(FVector2D(SampleX * 2.0f / View.ViewRect.Width(), SampleY * -2.0f / View.ViewRect.Height()));
		}

		// Setup a new FPreviousViewInfo from current frame infos.
		FPreviousViewInfo NewPrevViewInfo;
		{
			NewPrevViewInfo.ViewRect = View.ViewRect;
			NewPrevViewInfo.ViewMatrices = View.ViewMatrices;
		}

		if ( ViewState )
		{
			// update previous frame matrices in case world origin was rebased on this frame
			if (!View.OriginOffsetThisFrame.IsZero())
			{
				ViewState->PrevFrameViewInfo.ViewMatrices.ApplyWorldOffset(View.OriginOffsetThisFrame);
			}

			// determine if we are initializing or we should reset the persistent state
			const float DeltaTime = View.Family->Time.GetRealTimeSeconds() - ViewState->LastRenderTime;
			const bool bFirstFrameOrTimeWasReset = DeltaTime < -0.0001f || ViewState->LastRenderTime < 0.0001f;
			const bool bIsLargeCameraMovement = IsLargeCameraMovement(
				View,
				ViewState->PrevFrameViewInfo.ViewMatrices.GetViewMatrix(),
				ViewState->PrevFrameViewInfo.ViewMatrices.GetViewOrigin(),
				75.0f, GCameraCutTranslationThreshold);
			const bool bResetCamera = (bFirstFrameOrTimeWasReset || View.bCameraCut || bIsLargeCameraMovement || View.bForceCameraVisibilityReset);
			
#if RHI_RAYTRACING
			static const auto CVarTemporalDenoiser = IConsoleManager::Get().FindTConsoleVariableDataInt(TEXT("r.PathTracing.TemporalDenoiser.mode"));
			const int TemporalDenoiserMode = CVarTemporalDenoiser ? CVarTemporalDenoiser->GetValueOnAnyThread() : 0;

			if (View.bIsOfflineRender)
			{
				// In the offline context, we want precise control over when to restart the path tracer's accumulation to allow for motion blur
				// So we use the camera cut signal only. In particular - we should not use bForceCameraVisibilityReset since this has
				// interactions with the motion blur post process effect in tiled rendering (see comment below).
				if (View.bCameraCut || View.bForcePathTracerReset)
				{
					const bool bClearTemporalDenoisingHistory = (TemporalDenoiserMode == 1) ? View.bCameraCut : true;
					ViewState->PathTracingInvalidate(bClearTemporalDenoisingHistory);
				}
			}
			else
			{
				// for interactive usage - any movement or scene change should restart the path tracer

				// Note: 0.18 deg is the minimum angle for avoiding numerical precision issue (which would cause constant invalidation)
				const bool bIsCameraMove = IsLargeCameraMovement(
					View,
					ViewState->PrevFrameViewInfo.ViewMatrices.GetViewMatrix(),
					ViewState->PrevFrameViewInfo.ViewMatrices.GetViewOrigin(),
					0.18f /*degree*/, 0.1f /*cm*/);
				const bool bIsProjMatrixDifferent = View.ViewMatrices.GetProjectionNoAAMatrix() != View.ViewState->PrevFrameViewInfo.ViewMatrices.GetProjectionNoAAMatrix();

				// For each view, we remember what the invalidation counter was set to last time we were here so we can catch all changes
				const bool bNeedsInvalidation = ViewState->PathTracingInvalidationCounter != CurrentPathTracingInvalidationCounter;
				ViewState->PathTracingInvalidationCounter = CurrentPathTracingInvalidationCounter;
				if (bNeedsInvalidation ||
					bIsProjMatrixDifferent ||
					bIsCameraMove ||
					View.bCameraCut ||
					View.bForceCameraVisibilityReset ||
					View.bForcePathTracerReset)
				{
					const bool bClearTemporalDenoisingHistory = (TemporalDenoiserMode == 2) ? View.bCameraCut : true;
					ViewState->PathTracingInvalidate(bClearTemporalDenoisingHistory);
				}
			}

#endif // RHI_RAYTRACING

			if (bResetCamera)
			{
				View.PrevViewInfo = NewPrevViewInfo;

				// PT: If the motion blur shader is the last shader in the post-processing chain then it is the one that is
				//     adjusting for the viewport offset.  So it is always required and we can't just disable the work the
				//     shader does.  The correct fix would be to disable the effect when we don't need it and to properly mark
				//     the uber-postprocessing effect as the last effect in the chain.

				View.bPrevTransformsReset = true;
			}
			else
			{
				View.PrevViewInfo = ViewState->PrevFrameViewInfo;
			}

			// Replace previous view info of the view state with this frame, clearing out references over render target.
			if (!View.bStatePrevViewInfoIsReadOnly)
			{
				ViewState->PrevFrameViewInfo = NewPrevViewInfo;
			}

			// If the view has a previous view transform, then overwrite the previous view info for the _current_ frame.
			if (View.PreviousViewTransform.IsSet())
			{
				// Note that we must ensure this transform ends up in ViewState->PrevFrameViewInfo else it will be used to calculate the next frame's motion vectors as well
				View.PrevViewInfo.ViewMatrices.UpdateViewMatrix(View.PreviousViewTransform->GetTranslation(), View.PreviousViewTransform->GetRotation().Rotator());
			}

			// detect conditions where we should reset occlusion queries
			if (bFirstFrameOrTimeWasReset || 
				ViewState->LastRenderTime + GEngine->PrimitiveProbablyVisibleTime < View.Family->Time.GetRealTimeSeconds() ||
				View.bCameraCut ||
				View.bForceCameraVisibilityReset ||
				IsLargeCameraMovement(
					View, 
				    FMatrix(ViewState->PrevViewMatrixForOcclusionQuery), 
				    ViewState->PrevViewOriginForOcclusionQuery, 
				    GEngine->CameraRotationThreshold, GEngine->CameraTranslationThreshold))
			{
				View.bIgnoreExistingQueries = true;
				View.bDisableDistanceBasedFadeTransitions = true;
			}

			// Turn on/off round-robin occlusion querying in the ViewState
			static const auto CVarRROCC = IConsoleManager::Get().FindTConsoleVariableDataInt(TEXT("vr.RoundRobinOcclusion"));
			const bool bEnableRoundRobin = CVarRROCC ? (CVarRROCC->GetValueOnAnyThread() != false) : false;
			if (bEnableRoundRobin != ViewState->IsRoundRobinEnabled())
			{
				ViewState->UpdateRoundRobin(bEnableRoundRobin);
				View.bIgnoreExistingQueries = true;
			}

			ViewState->PrevViewMatrixForOcclusionQuery = FMatrix44f(View.ViewMatrices.GetViewMatrix());	// LWC_TODO: Precision loss
			ViewState->PrevViewOriginForOcclusionQuery = View.ViewMatrices.GetViewOrigin();

			// we don't use DeltaTime as it can be 0 (in editor) and is computed by subtracting floats (loses precision over time)
			// Clamp DeltaWorldTime to reasonable values for the purposes of motion blur, things like TimeDilation can make it very small
			// Offline renders always control the timestep for the view and always need the timescales calculated.
			if (!ViewFamily.bWorldIsPaused || View.bIsOfflineRender)
			{
				ViewState->UpdateMotionBlurTimeScale(View);
			}
			

			ViewState->PrevFrameNumber = ViewState->PendingPrevFrameNumber;
			ViewState->PendingPrevFrameNumber = View.Family->FrameNumber;

			// This finishes the update of view state
			ViewState->UpdateLastRenderTime(*View.Family);

			ViewState->UpdateTemporalLODTransition(View);
		}
		else
		{
			// Without a viewstate, we just assume that camera has not moved.
			View.PrevViewInfo = NewPrevViewInfo;
		}
	}
}

void FSceneViewState::UpdateMotionBlurTimeScale(const FViewInfo& View)
{
	const int32 MotionBlurTargetFPS = View.FinalPostProcessSettings.MotionBlurTargetFPS;

	// Ensure we can divide by the Delta Time later without a divide by zero.
	float DeltaRealTime = FMath::Max(View.Family->Time.GetDeltaRealTimeSeconds(), SMALL_NUMBER);

	// Track the current FPS by using an exponential moving average of the current delta time.
	if (MotionBlurTargetFPS <= 0)
	{
		// Keep motion vector lengths stable for paused sequencer frames.
		if (GetSequencerState() == ESS_Paused)
		{
			// Reset the moving average to the current delta time.
			MotionBlurTargetDeltaTime = DeltaRealTime;
		}
		else
		{
			// Smooth the target delta time using a moving average.
			MotionBlurTargetDeltaTime = FMath::Lerp(MotionBlurTargetDeltaTime, DeltaRealTime, 0.1f);
		}
	}
	else // Track a fixed target FPS.
	{
		// Keep motion vector lengths stable for paused sequencer frames. Assumes a 60 FPS tick.
		// Tuned for content compatibility with existing content when target is the default 30 FPS.
		if (GetSequencerState() == ESS_Paused)
		{
			DeltaRealTime = 1.0f / 60.0f;
		}


		MotionBlurTargetDeltaTime = 1.0f / static_cast<float>(MotionBlurTargetFPS);
	}

	MotionBlurTimeScale = MotionBlurTargetDeltaTime / DeltaRealTime;
}

void FDeferredShadingSceneRenderer::ComputeLightVisibility()
{
	FSceneRenderer::ComputeLightVisibility();

	CreateIndirectCapsuleShadows();

	SetupVolumetricFog();
}

void FSceneRenderer::ComputeLightVisibility()
{
	QUICK_SCOPE_CYCLE_COUNTER(STAT_PostVisibilityFrameSetup_Light_Visibility);

	VisibleLightInfos.AddDefaulted(Scene->Lights.GetMaxIndex());

	for (int32 ViewIndex = 0; ViewIndex < Views.Num(); ViewIndex++)
	{
		FViewInfo& View = Views[ViewIndex];
		View.VisibleLightInfos.Empty(Scene->Lights.GetMaxIndex());

		for (int32 LightIndex = 0; LightIndex < Scene->Lights.GetMaxIndex(); LightIndex++)
		{
			new (View.VisibleLightInfos) FVisibleLightViewInfo();
		}
	}

	const bool bSetupMobileLightShafts = FeatureLevel <= ERHIFeatureLevel::ES3_1 && ShouldRenderLightShafts(ViewFamily);

	// determine visibility of each light
	for(auto LightIt = Scene->Lights.CreateConstIterator();LightIt;++LightIt)
	{
		const FLightSceneInfoCompact& LightSceneInfoCompact = *LightIt;
		const FLightSceneInfo* LightSceneInfo = LightSceneInfoCompact.LightSceneInfo;

		// view frustum cull lights in each view
		for(int32 ViewIndex = 0;ViewIndex < Views.Num();ViewIndex++)
		{		
			const FLightSceneProxy* Proxy = LightSceneInfo->Proxy;
			FViewInfo& View = Views[ViewIndex];
			FVisibleLightViewInfo& VisibleLightViewInfo = View.VisibleLightInfos[LightIt.GetIndex()];
			// dir lights are always visible, and point/spot only if in the frustum
			if( Proxy->GetLightType() == LightType_Point ||
				Proxy->GetLightType() == LightType_Spot ||
				Proxy->GetLightType() == LightType_Rect )
			{
				const FSphere& BoundingSphere = Proxy->GetBoundingSphere();
				const bool bInViewFrustum = View.GetCullingFrustum().IntersectSphere(BoundingSphere.Center, BoundingSphere.W);

				if (View.IsPerspectiveProjection())
				{
					const float DistanceSquared = (BoundingSphere.Center - View.CullingOrigin).SizeSquared();
					const float ProxyMaxDistance = Proxy->GetMaxDrawDistance();
					const float ScaledMaxDistance = ProxyMaxDistance * GLightMaxDrawDistanceScale;
					const bool bDrawLight = (FMath::Square(FMath::Min(0.0002f, GMinScreenRadiusForLights / BoundingSphere.W) * View.LODDistanceFactor) * DistanceSquared < 1.0f)
												&& (ProxyMaxDistance <= 0.0 || DistanceSquared < FMath::Square(ScaledMaxDistance));
							
					VisibleLightViewInfo.bInViewFrustum = bDrawLight && bInViewFrustum;
					VisibleLightViewInfo.bInDrawRange = bDrawLight;
				}
				else
				{
					VisibleLightViewInfo.bInViewFrustum = bInViewFrustum;
					VisibleLightViewInfo.bInDrawRange = true;
				}
			}
			else
			{
				VisibleLightViewInfo.bInViewFrustum = true;
				VisibleLightViewInfo.bInDrawRange = true;
				// Setup single sun-shaft from direction lights for mobile.
				if (bSetupMobileLightShafts && LightSceneInfo->bEnableLightShaftBloom && ShouldRenderLightShaftsForLight(View, *LightSceneInfo->Proxy))
				{
					View.MobileLightShaft = GetMobileLightShaftInfo(View, *LightSceneInfo);
				}
			}

			// Draw shapes for reflection captures
			if( View.bIsReflectionCapture 
				&& VisibleLightViewInfo.bInViewFrustum
				&& Proxy->HasStaticLighting() 
				&& Proxy->GetLightType() != LightType_Directional )
			{
				FVector Origin = Proxy->GetOrigin();
				FVector ToLight = Origin - View.ViewMatrices.GetViewOrigin();
				float DistanceSqr = ToLight | ToLight;
				float Radius = Proxy->GetRadius();

				if( DistanceSqr < Radius * Radius )
				{
					View.VisibleReflectionCaptureLights.Emplace(Proxy);
				}
			}
		}
	}

	InitFogConstants();
}

void FSceneRenderer::GatherReflectionCaptureLightMeshElements()
{
	// view frustum cull lights in each view
	for (FViewInfo& View : Views)
	{
		for (const FLightSceneProxy* Proxy : View.VisibleReflectionCaptureLights)
		{
			FVector Origin = Proxy->GetOrigin();
			FVector ToLight = Origin - View.ViewMatrices.GetViewOrigin();
			float DistanceSqr = ToLight | ToLight;
			float Radius = Proxy->GetRadius();

			FLightRenderParameters LightParameters;
			Proxy->GetLightShaderParameters(LightParameters);

			// Force to be at least 0.75 pixels
			float CubemapSize = (float)IConsoleManager::Get().FindTConsoleVariableDataInt(TEXT("r.ReflectionCaptureResolution"))->GetValueOnAnyThread();
			float Distance = FMath::Sqrt(DistanceSqr);
			float MinRadius = Distance * 0.75f / CubemapSize;
			LightParameters.SourceRadius = FMath::Max(MinRadius, LightParameters.SourceRadius);

			// Snap to cubemap pixel center to reduce aliasing
			FVector Scale = ToLight.GetAbs();
			int32 MaxComponent = Scale.X > Scale.Y ? (Scale.X > Scale.Z ? 0 : 2) : (Scale.Y > Scale.Z ? 1 : 2);
			for (int32 k = 1; k < 3; k++)
			{
				float Projected = ToLight[(MaxComponent + k) % 3] / Scale[MaxComponent];
				float Quantized = (FMath::RoundToFloat(Projected * (0.5f * CubemapSize) - 0.5f) + 0.5f) / (0.5f * CubemapSize);
				ToLight[(MaxComponent + k) % 3] = Quantized * Scale[MaxComponent];
			}
			Origin = ToLight + View.ViewMatrices.GetViewOrigin();

			FLinearColor Color(LightParameters.Color.R, LightParameters.Color.G, LightParameters.Color.B, LightParameters.FalloffExponent);
			const bool bIsRectLight = Proxy->IsRectLight();
			if (!bIsRectLight)
			{
				const float SphereArea = (4.0f * PI) * FMath::Square(LightParameters.SourceRadius);
				const float CylinderArea = (2.0f * PI) * LightParameters.SourceRadius * LightParameters.SourceLength;
				const float SurfaceArea = SphereArea + CylinderArea;
				Color *= 4.0f / SurfaceArea;
			}

			if (Proxy->IsInverseSquared())
			{
				float LightRadiusMask = FMath::Square(1.0f - FMath::Square(DistanceSqr * FMath::Square(LightParameters.InvRadius)));
				Color.A = LightRadiusMask;
			}
			else
			{
				// Remove inverse square falloff
				Color *= DistanceSqr + 1.0f;

				// Apply falloff
				Color.A = FMath::Pow(1.0f - DistanceSqr * FMath::Square(LightParameters.InvRadius), LightParameters.FalloffExponent);
			}

			// Spot falloff
			FVector L = ToLight.GetSafeNormal();
			Color.A *= FMath::Square(FMath::Clamp(((L | (FVector)LightParameters.Direction) - LightParameters.SpotAngles.X) * LightParameters.SpotAngles.Y, 0.0f, 1.0f));

			Color.A *= LightParameters.SpecularScale;

			// Rect is one sided
			if (bIsRectLight && (L | (FVector)LightParameters.Direction) < 0.0f)
				continue;

			UTexture* SurfaceTexture = nullptr;
			if (bIsRectLight)
			{
				const FRectLightSceneProxy* RectLightProxy = (const FRectLightSceneProxy*)Proxy;
				SurfaceTexture = RectLightProxy->SourceTexture;
			}

			FMaterialRenderProxy* ColoredMeshInstance = nullptr;
			if (SurfaceTexture)
			{
				ColoredMeshInstance = Allocator.Create<FColoredTexturedMaterialRenderProxy>(GEngine->EmissiveMeshMaterial->GetRenderProxy(), Color, NAME_Color, SurfaceTexture, NAME_LinearColor);
			}
			else
			{
				ColoredMeshInstance = Allocator.Create<FColoredMaterialRenderProxy>(GEngine->EmissiveMeshMaterial->GetRenderProxy(), Color, NAME_Color);
			}

			FMatrix LightToWorld = Proxy->GetLightToWorld();
			LightToWorld.RemoveScaling();

			FViewElementPDI LightPDI(&View, NULL, &View.DynamicPrimitiveCollector);

			if (bIsRectLight)
			{
				DrawBox(&LightPDI, LightToWorld, FVector(0.0f, LightParameters.SourceRadius, LightParameters.SourceLength), ColoredMeshInstance, SDPG_World);
			}
			else if (LightParameters.SourceLength > 0.0f)
			{
				DrawSphere(&LightPDI, Origin + 0.5f * LightParameters.SourceLength * LightToWorld.GetUnitAxis(EAxis::Z), FRotator::ZeroRotator, LightParameters.SourceRadius * FVector::OneVector, 36, 24, ColoredMeshInstance, SDPG_World);
				DrawSphere(&LightPDI, Origin - 0.5f * LightParameters.SourceLength * LightToWorld.GetUnitAxis(EAxis::Z), FRotator::ZeroRotator, LightParameters.SourceRadius * FVector::OneVector, 36, 24, ColoredMeshInstance, SDPG_World);
				DrawCylinder(&LightPDI, Origin, LightToWorld.GetUnitAxis(EAxis::X), LightToWorld.GetUnitAxis(EAxis::Y), LightToWorld.GetUnitAxis(EAxis::Z), LightParameters.SourceRadius, 0.5f * LightParameters.SourceLength, 36, ColoredMeshInstance, SDPG_World);
			}
			else
			{
				DrawSphere(&LightPDI, Origin, FRotator::ZeroRotator, LightParameters.SourceRadius * FVector::OneVector, 36, 24, ColoredMeshInstance, SDPG_World);
			}
		}

		View.VisibleReflectionCaptureLights.Empty();
	}
}

void FSceneRenderer::PostVisibilityFrameSetup(FILCUpdatePrimTaskData*& OutILCTaskData)
{
	if (GetRendererOutput() != ERendererOutput::FinalSceneColor)
	{
		return;
	}

	QUICK_SCOPE_CYCLE_COUNTER(STAT_PostVisibilityFrameSetup);

	{
		QUICK_SCOPE_CYCLE_COUNTER(STAT_PostVisibilityFrameSetup_Sort);
		for (int32 ViewIndex = 0; ViewIndex < Views.Num(); ViewIndex++)
		{		
			FViewInfo& View = Views[ViewIndex];

			if (View.State)
			{
				((FSceneViewState*)View.State)->TrimHistoryRenderTargets(Scene);
			}
		}
	}

	GatherReflectionCaptureLightMeshElements();

	if (ViewFamily.EngineShowFlags.HitProxies == 0 && Scene->PrecomputedLightVolumes.Num() > 0
		&& GILCUpdatePrimTaskEnabled && FPlatformProcess::SupportsMultithreading())
	{
		OutILCTaskData = Allocator.Create<FILCUpdatePrimTaskData>();
		Scene->IndirectLightingCache.StartUpdateCachePrimitivesTask(Scene, *this, true, *OutILCTaskData);
		check(OutILCTaskData->TaskRef.IsValid());
	}
}

uint32 GetShadowQuality();
void UpdateHairResources(FRDGBuilder& GraphBuilder, const FViewInfo& View);

/** 
* Performs once per frame setup prior to visibility determination.
*/
void FDeferredShadingSceneRenderer::PreVisibilityFrameSetup(FRDGBuilder& GraphBuilder)
{
	// Possible stencil dither optimization approach
	for (int32 ViewIndex = 0; ViewIndex < Views.Num(); ViewIndex++)
	{
		FViewInfo& View = Views[ViewIndex];
		View.bAllowStencilDither = DepthPass.bDitheredLODTransitionsUseStencil;
	}

	FSceneRenderer::PreVisibilityFrameSetup(GraphBuilder);
}

/**
 * Initialize scene's views.
 * Check visibility, build visible mesh commands, etc.
 */
void FDeferredShadingSceneRenderer::BeginInitViews(
	FRDGBuilder& GraphBuilder,
	const FSceneTexturesConfig& SceneTexturesConfig,
	FInstanceCullingManager& InstanceCullingManager,
	FRDGExternalAccessQueue& ExternalAccessQueue,
	FInitViewTaskDatas& TaskDatas)
{
	SCOPED_NAMED_EVENT(FDeferredShadingSceneRenderer_InitViews, FColor::Emerald);
	SCOPE_CYCLE_COUNTER(STAT_InitViewsTime);
	RDG_CSV_STAT_EXCLUSIVE_SCOPE(GraphBuilder, InitViews_Scene);

	const bool bRendererOutputFinalSceneColor = (GetRendererOutput() == ERendererOutput::FinalSceneColor);

	PreVisibilityFrameSetup(GraphBuilder);

	{
		// This is to init the ViewUniformBuffer before rendering for the Niagara compute shader.
		// This needs to run before ComputeViewVisibility() is called, but the views normally initialize the ViewUniformBuffer after that (at the end of this method).
		// Note: This MUST happen before we start to execute GDME tasks of any kind otherwise we will race with PostInitViews renderers!
		if (FXSystem && FXSystem->RequiresEarlyViewUniformBuffer() && Views.IsValidIndex(0) && bRendererOutputFinalSceneColor)
		{
			// during ISR, instanced view RHI resources need to be initialized first.
			if (FViewInfo* InstancedView = const_cast<FViewInfo*>(Views[0].GetInstancedView()))
			{
				InstancedView->InitRHIResources();
			}
			Views[0].InitRHIResources();
			FXSystem->PostInitViews(GraphBuilder, GetSceneViews(), !ViewFamily.EngineShowFlags.HitProxies);
		}
	}

	// Start processing dynamic mesh elements tasks early enough to overlap with shadows and GPU scene update.
	TaskDatas.VisibilityTaskData->StartGatherDynamicMeshElements();

#if RHI_RAYTRACING
	// Start processing dynamic ray tracing instances early enough to overlap with shadows and GPU scene update.
	if (TaskDatas.RayTracingGatherInstances != nullptr)
	{
		RayTracing::BeginGatherDynamicRayTracingInstances(*TaskDatas.RayTracingGatherInstances);
	}
#endif

	if (!ViewFamily.EngineShowFlags.HitProxies)
	{
		TaskDatas.Decals = FDecalVisibilityTaskData::Launch(GraphBuilder, *Scene, Views);
	}

	// Attempt to launch dynamic shadow tasks early before finalizing visibility.
	if (bRendererOutputFinalSceneColor)
	{
		BeginInitDynamicShadows(GraphBuilder, TaskDatas, InstanceCullingManager);
	}

	FRHICommandListImmediate& RHICmdList = GraphBuilder.RHICmdList;

	if (InstanceCullingManager.IsEnabled()
		&& Scene->InstanceCullingOcclusionQueryRenderer
		&& Scene->InstanceCullingOcclusionQueryRenderer->InstanceOcclusionQueryBuffer)
	{
		InstanceCullingManager.InstanceOcclusionQueryBuffer = GraphBuilder.RegisterExternalBuffer(Scene->InstanceCullingOcclusionQueryRenderer->InstanceOcclusionQueryBuffer);
		InstanceCullingManager.InstanceOcclusionQueryBufferFormat = Scene->InstanceCullingOcclusionQueryRenderer->InstanceOcclusionQueryBufferFormat;
	}

	// Create GPU-side representation of the view for instance culling.
	for (FViewInfo* ViewInfo : AllViews)
	{
		uint32 InstanceFactor = ViewInfo->bIsInstancedStereoEnabled && IStereoRendering::IsStereoEyeView(*ViewInfo) && GEngine->StereoRenderingDevice.IsValid() ?
			GEngine->StereoRenderingDevice->GetDesiredNumberOfViews(true) : 1;

		ViewInfo->InstanceFactor = InstanceFactor > 0 ? InstanceFactor : 1;
	}

	LumenScenePDIVisualization();

	// This must happen before we start initialising and using views.
	UpdateSkyIrradianceGpuBuffer(GraphBuilder, ViewFamily.EngineShowFlags, Scene->SkyLight, Scene->SkyIrradianceEnvironmentMap);

	// Initialise Sky/View resources before the view global uniform buffer is built.
	if (ShouldRenderSkyAtmosphere(Scene, ViewFamily.EngineShowFlags))
	{
		InitSkyAtmosphereForViews(RHICmdList, GraphBuilder);
	}

	{
		QUICK_SCOPE_CYCLE_COUNTER(STAT_InitViews_InitRHIResources);
		// initialize per-view uniform buffer. Do it from back to front because secondary stereo view follows its primary one, but primary needs to know the instanced's params
		for (int32 ViewIndex = Views.Num() - 1; ViewIndex >= 0; --ViewIndex)
		{
			FViewInfo& View = Views[ViewIndex];
			// Set the pre-exposure before initializing the constant buffers.
			View.UpdatePreExposure();

			// Initialize the view's RHI resources.
			UpdateHairResources(GraphBuilder, View);
			View.InitRHIResources();
		}

		for (FCustomRenderPassInfo& PassInfo : CustomRenderPassInfos)
		{
			for (FViewInfo& View : PassInfo.Views)
			{
				View.InitRHIResources();
			}
		}
	}

	TaskDatas.VisibilityTaskData->ProcessRenderThreadTasks();

	// Make a second attempt to launch shadow tasks it wasn't able to the first time due to visibility being deferred.
	if (bRendererOutputFinalSceneColor)
	{
		BeginInitDynamicShadows(GraphBuilder, TaskDatas, InstanceCullingManager);
	}

	PostVisibilityFrameSetup(TaskDatas.ILCUpdatePrim);
}

void FSceneRenderer::SetupSceneReflectionCaptureBuffer(FRHICommandListImmediate& RHICmdList)
{
	const TArray<FReflectionCaptureSortData>& SortedCaptures = Scene->ReflectionSceneData.SortedCaptures;

	for (int32 ViewIndex = 0; ViewIndex < Views.Num(); ++ViewIndex)
	{
		FViewInfo& View = Views[ViewIndex];

		if (IsMobilePlatform(ShaderPlatform))
		{
			View.MobileReflectionCaptureUniformBuffer = Scene->ReflectionSceneData.MobileReflectionCaptureUniformBuffer;
		}
		else
		{
			View.ReflectionCaptureUniformBuffer = Scene->ReflectionSceneData.ReflectionCaptureUniformBuffer;
		}
		
		View.NumBoxReflectionCaptures = 0;
		View.NumSphereReflectionCaptures = 0;
		View.FurthestReflectionCaptureDistance = 0.0f;

		if (View.Family->EngineShowFlags.ReflectionEnvironment 
			// Avoid feedback
			&& !View.bIsReflectionCapture)
		{
			View.NumBoxReflectionCaptures = Scene->ReflectionSceneData.NumBoxCaptures;
			View.NumSphereReflectionCaptures = Scene->ReflectionSceneData.NumSphereCaptures;

			for (int32 CaptureIndex = 0; CaptureIndex < SortedCaptures.Num(); CaptureIndex++)
			{
				const FSphere BoundingSphere(SortedCaptures[CaptureIndex].Position.GetVector3d(), SortedCaptures[CaptureIndex].Radius);

				const float Distance = View.ViewMatrices.GetViewMatrix().TransformPosition(BoundingSphere.Center).Z + BoundingSphere.W;

				View.FurthestReflectionCaptureDistance = FMath::Max(View.FurthestReflectionCaptureDistance, Distance);
			}
		}
	}
}

void FDeferredShadingSceneRenderer::EndInitViews(
	FRDGBuilder& GraphBuilder,
	FLumenSceneFrameTemporaries& FrameTemporaries,
	FInstanceCullingManager& InstanceCullingManager,
	FInitViewTaskDatas& TaskDatas)
{
	SCOPED_NAMED_EVENT(FDeferredShadingSceneRenderer_InitViewsAfterPrepass, FColor::Emerald);
	SCOPE_CYCLE_COUNTER(STAT_InitViewsPossiblyAfterPrepass);

	TaskDatas.VisibilityTaskData->Finish();

	// Trigger shadow GDME tasks after the main visibility tasks are synced. Projection stencil shadows reference the main view dynamic elements.
	BeginShadowGatherDynamicMeshElements(TaskDatas.DynamicShadows);

	FRHICommandListImmediate& RHICmdList = GraphBuilder.RHICmdList;

	// If parallel ILC update is disabled, then process it in place.
	if (ViewFamily.EngineShowFlags.HitProxies == 0
		&& Scene->PrecomputedLightVolumes.Num() > 0
		&& !(GILCUpdatePrimTaskEnabled && FPlatformProcess::SupportsMultithreading()))
	{
		QUICK_SCOPE_CYCLE_COUNTER(STAT_PostVisibilityFrameSetup_IndirectLightingCache_Update);
		check(!TaskDatas.ILCUpdatePrim);
		Scene->IndirectLightingCache.UpdateCache(Scene, *this, true);
	}

	// If we kicked off ILC update via task, wait and finalize.
	if (TaskDatas.ILCUpdatePrim)
	{
		Scene->IndirectLightingCache.FinalizeCacheUpdates(Scene, *this, *TaskDatas.ILCUpdatePrim);
	}

	{
		QUICK_SCOPE_CYCLE_COUNTER(STAT_InitViews_UpdatePrimitiveIndirectLightingCacheBuffers);
		// Now that the indirect lighting cache is updated, we can update the primitive precomputed lighting buffers.
		UpdatePrimitiveIndirectLightingCacheBuffers(GraphBuilder.RHICmdList);
	}

	SeparateTranslucencyDimensions = UpdateSeparateTranslucencyDimensions(*this);

	SetupSceneReflectionCaptureBuffer(RHICmdList);

	if (IsForwardShadingEnabled(ShaderPlatform))
	{
		// Dynamic shadows are synced earlier when forward shading is enabled.
		FinishInitDynamicShadows(GraphBuilder, TaskDatas.DynamicShadows, InstanceCullingManager);
	}
}

/*------------------------------------------------------------------------------
	FLODSceneTree Implementation
------------------------------------------------------------------------------*/
void FLODSceneTree::AddChildNode(const FPrimitiveComponentId ParentId, FPrimitiveSceneInfo* ChildSceneInfo)
{
	if (ParentId.IsValid() && ChildSceneInfo)
	{
		FLODSceneNode* Parent = SceneNodes.Find(ParentId);

		// If parent SceneNode hasn't been created yet (possible, depending on the order actors are added to the scene)
		if (!Parent)
		{
			// Create parent SceneNode, assign correct SceneInfo
			Parent = &SceneNodes.Add(ParentId, FLODSceneNode());

			int32 ParentIndex = Scene->PrimitiveComponentIds.Find(ParentId);
			if (ParentIndex != INDEX_NONE)
			{
				Parent->SceneInfo = Scene->Primitives[ParentIndex];
				check(Parent->SceneInfo->PrimitiveComponentId == ParentId);
			}
		}

		Parent->AddChild(ChildSceneInfo);
	}
}

void FLODSceneTree::RemoveChildNode(const FPrimitiveComponentId ParentId, FPrimitiveSceneInfo* ChildSceneInfo)
{
	if (ParentId.IsValid() && ChildSceneInfo)
	{
		if (FLODSceneNode* Parent = SceneNodes.Find(ParentId))
		{
			Parent->RemoveChild(ChildSceneInfo);

			// Delete from scene if no children remain
			if (Parent->ChildrenSceneInfos.Num() == 0)
			{
				SceneNodes.Remove(ParentId);
			}
		}
	}
}

void FLODSceneTree::UpdateNodeSceneInfo(FPrimitiveComponentId NodeId, FPrimitiveSceneInfo* SceneInfo)
{
	if (FLODSceneNode* Node = SceneNodes.Find(NodeId))
	{
		Node->SceneInfo = SceneInfo;
	}
}

void FLODSceneTree::ClearVisibilityState(FViewInfo& View)
{
	if (FSceneViewState* ViewState = (FSceneViewState*)View.State)
	{
#if !(UE_BUILD_SHIPPING || UE_BUILD_TEST)
		// Skip update logic when frozen
		if (ViewState->bIsFrozen)
		{
			return;
		}
#endif
		FHLODVisibilityState& HLODState = ViewState->HLODVisibilityState;

		if(HLODState.IsValidPrimitiveIndex(0))
		{
			HLODState.PrimitiveFadingLODMap.Empty(0);
			HLODState.PrimitiveFadingOutLODMap.Empty(0);
			HLODState.ForcedVisiblePrimitiveMap.Empty(0);
			HLODState.ForcedHiddenPrimitiveMap.Empty(0);
		}

		TMap<FPrimitiveComponentId, FHLODSceneNodeVisibilityState>& VisibilityStates = ViewState->HLODSceneNodeVisibilityStates;

		if(VisibilityStates.Num() > 0)
		{
			VisibilityStates.Empty(0);
		}
	}
}

void FLODSceneTree::UpdateVisibilityStates(FViewInfo& View, UE::Tasks::FTaskEvent& FlushCachedShadowsTaskEvent)
{
	if (FSceneViewState* ViewState = (FSceneViewState*)View.State)
	{
#if !(UE_BUILD_SHIPPING || UE_BUILD_TEST)
		// Skip update logic when frozen
		if (ViewState->bIsFrozen)
		{
			return;
		}
#endif
		QUICK_SCOPE_CYCLE_COUNTER(STAT_ViewVisibilityTime_HLODUpdate);

		// Per-frame initialization
		FHLODVisibilityState& HLODState = ViewState->HLODVisibilityState;
		TMap<FPrimitiveComponentId, FHLODSceneNodeVisibilityState>& VisibilityStates = ViewState->HLODSceneNodeVisibilityStates;

		HLODState.PrimitiveFadingLODMap.Init(false, Scene->Primitives.Num());
		HLODState.PrimitiveFadingOutLODMap.Init(false, Scene->Primitives.Num());
		HLODState.ForcedVisiblePrimitiveMap.Init(false, Scene->Primitives.Num());
		HLODState.ForcedHiddenPrimitiveMap.Init(false, Scene->Primitives.Num());
		TArray<FPrimitiveViewRelevance, SceneRenderingAllocator>& RelevanceMap = View.PrimitiveViewRelevanceMap;

		if (HLODState.PrimitiveFadingLODMap.Num() != Scene->Primitives.Num())
		{
			checkf(0, TEXT("HLOD update incorrectly allocated primitive maps"));
			return;
		}

		TArray<FPrimitiveSceneInfo*, SceneRenderingAllocator> FlushCachedShadowPrimitives;

		int32 UpdateCount = ++HLODState.UpdateCount;

		// Update persistent state on temporal dither sync frames
		const FTemporalLODState& LODState = ViewState->GetTemporalLODState();
		bool bSyncFrame = false;
		
		if (HLODState.TemporalLODSyncTime != LODState.TemporalLODTime[0])
		{
			HLODState.TemporalLODSyncTime = LODState.TemporalLODTime[0];
			bSyncFrame = true;

			// Only update our scaling on sync frames else we might end up changing transition direction mid-fade	
			const FCachedSystemScalabilityCVars& ScalabilityCVars = GetCachedScalabilityCVars();
			if (ScalabilityCVars.FieldOfViewAffectsHLOD)
			{
				HLODState.FOVDistanceScaleSq = ScalabilityCVars.CalculateFieldOfViewDistanceScale(View.DesiredFOV);
				HLODState.FOVDistanceScaleSq *= HLODState.FOVDistanceScaleSq;
			}
			else
			{
				HLODState.FOVDistanceScaleSq = 1.f;
			}
		}

		for (auto Iter = SceneNodes.CreateIterator(); Iter; ++Iter)
		{
			FLODSceneNode& Node = Iter.Value();
			FPrimitiveSceneInfo* SceneInfo = Node.SceneInfo;

			if (!SceneInfo || !SceneInfo->PrimitiveComponentId.IsValid() || !SceneInfo->IsIndexValid())
			{
				continue;
			}

			FHLODSceneNodeVisibilityState& NodeVisibility = VisibilityStates.FindOrAdd(SceneInfo->PrimitiveComponentId);
			const TArray<FStaticMeshBatchRelevance>& NodeMeshRelevances = SceneInfo->StaticMeshRelevances;

			// Ignore already updated nodes, or those that we can't work with
			if (NodeVisibility.UpdateCount == UpdateCount || !NodeMeshRelevances.IsValidIndex(0))
			{
				continue;
			}

			const int32 NodeIndex = SceneInfo->GetIndex();

			if (!Scene->PrimitiveBounds.IsValidIndex(NodeIndex))
			{
				checkf(0, TEXT("A HLOD Node's PrimitiveSceneInfo PackedIndex was out of Scene.Primitive bounds!"));
				continue;
			}

			FPrimitiveBounds& Bounds = Scene->PrimitiveBounds[NodeIndex];
			const bool bForcedIntoView = FMath::IsNearlyZero(Bounds.MinDrawDistance);

			// Update visibility states of this node and owned children
			float ClosestDistSquared, FurthestDistSquared;

			if (GDistanceCullToSphereEdge)
			{
				ComputeDistances(Bounds, View.ViewMatrices.GetViewOrigin(), ClosestDistSquared, FurthestDistSquared);
			}
			else
			{
				ClosestDistSquared = FurthestDistSquared = Bounds.BoxSphereBounds.ComputeSquaredDistanceFromBoxToPoint(View.ViewMatrices.GetViewOrigin());
			}

			const bool bNearCulled = FurthestDistSquared  < FMath::Square(Bounds.MinDrawDistance) * HLODState.FOVDistanceScaleSq;
			const bool bFarCulled = ClosestDistSquared > Bounds.MaxDrawDistance * Bounds.MaxDrawDistance * HLODState.FOVDistanceScaleSq;

			const bool bIsInDrawRange = !bNearCulled && !bFarCulled;

			const bool bWasFadingPreUpdate = !!NodeVisibility.bIsFading;
			const bool bIsDitheredTransition = NodeMeshRelevances[0].bDitheredLODTransition;

			if (bIsDitheredTransition && !bForcedIntoView)
			{		
				// Update fading state with syncs
				if (bSyncFrame)
				{
					// Fade when HLODs change threshold
					const bool bChangedRange = bIsInDrawRange != !!NodeVisibility.bWasVisible;

					if (NodeVisibility.bIsFading)
					{
						NodeVisibility.bIsFading = false;
					}
					else if (bChangedRange)
					{
						NodeVisibility.bIsFading = true;
					}

					NodeVisibility.bWasVisible = NodeVisibility.bIsVisible;
					NodeVisibility.bIsVisible = bIsInDrawRange;
				}
			}
			else
			{
				// Instant transitions without dithering
				NodeVisibility.bWasVisible = NodeVisibility.bIsVisible;
				NodeVisibility.bIsVisible = bIsInDrawRange || bForcedIntoView;
				NodeVisibility.bIsFading = false;
			}

			// Flush cached lighting data when changing visible contents
			if (NodeVisibility.bIsVisible != NodeVisibility.bWasVisible || bWasFadingPreUpdate || NodeVisibility.bIsFading)
			{
				FlushCachedShadowPrimitives.Emplace(SceneInfo);
			}

			// Force fully disabled view relevance so shadows don't attempt to recompute
			if (!NodeVisibility.bIsVisible)
			{
				if (RelevanceMap.IsValidIndex(NodeIndex))
				{
					FPrimitiveViewRelevance& ViewRelevance = RelevanceMap[NodeIndex];
					FMemory::Memzero(&ViewRelevance, sizeof(FPrimitiveViewRelevance));
					ViewRelevance.bInitializedThisFrame = true;
				}
				else
				{
					checkf(0, TEXT("A HLOD Node's PrimitiveSceneInfo PackedIndex was out of View.Relevancy bounds!"));
				}
			}

			// NOTE: We update our children last as HideNodeChildren can add new visibility
			// states, potentially invalidating our cached reference above, NodeVisibility
			if (NodeVisibility.bIsFading)
			{
				// Fade until state back in sync
				HLODState.PrimitiveFadingLODMap[NodeIndex] = true;
				HLODState.PrimitiveFadingOutLODMap[NodeIndex] = !NodeVisibility.bIsVisible;
				HLODState.ForcedVisiblePrimitiveMap[NodeIndex] = true;
				ApplyNodeFadingToChildren(ViewState, Node, NodeVisibility, true, !!NodeVisibility.bIsVisible);
			}
			else if (NodeVisibility.bIsVisible)
			{
				// If stable and visible, override hierarchy visibility
				HLODState.ForcedVisiblePrimitiveMap[NodeIndex] = true;
				HideNodeChildren(ViewState, Node);
			}
			else
			{
				// Not visible and waiting for a transition to fade, keep HLOD hidden
				HLODState.ForcedHiddenPrimitiveMap[NodeIndex] = true;

				// Also hide children when performing far culling
				if (bFarCulled)
				{
					HideNodeChildren(ViewState, Node);
				}
			}
		}

		if (!FlushCachedShadowPrimitives.IsEmpty())
		{
			// We don't want to block on the LPI creation task as it overlaps with this work. Spawn a new task that will be waited on further down the pipe.
			FlushCachedShadowsTaskEvent.AddPrerequisites(UE::Tasks::Launch(UE_SOURCE_LOCATION, [this, Primitives = MoveTemp(FlushCachedShadowPrimitives)]
			{
				for (FPrimitiveSceneInfo* SceneInfo : Primitives)
				{
					FLightPrimitiveInteraction* NodeLightList = SceneInfo->LightList;
					while (NodeLightList)
					{
						NodeLightList->FlushCachedShadowMapData();
						NodeLightList = NodeLightList->GetNextLight();
					}
				}
			}, Scene->GetCreateLightPrimitiveInteractionsTask()));
		}
	}
}

void FLODSceneTree::ApplyNodeFadingToChildren(FSceneViewState* ViewState, FLODSceneNode& Node, FHLODSceneNodeVisibilityState& NodeVisibility, const bool bIsFading, const bool bIsFadingOut)
{
	checkSlow(ViewState);
	if (Node.SceneInfo)
	{
		FHLODVisibilityState& HLODState = ViewState->HLODVisibilityState;
		NodeVisibility.UpdateCount = HLODState.UpdateCount;

		// Force visibility during fades
		for (const auto Child : Node.ChildrenSceneInfos)
		{
			if (!Child || !Child->PrimitiveComponentId.IsValid() || !Child->IsIndexValid())
			{
				continue;
			}

			const int32 ChildIndex = Child->GetIndex();

			if (!HLODState.PrimitiveFadingLODMap.IsValidIndex(ChildIndex))
			{
				checkf(0, TEXT("A HLOD Child's PrimitiveSceneInfo PackedIndex was out of FadingMap's bounds!"));
				continue;
			}
		
			HLODState.PrimitiveFadingLODMap[ChildIndex] = bIsFading;
			HLODState.PrimitiveFadingOutLODMap[ChildIndex] = bIsFadingOut;
			HLODState.ForcedHiddenPrimitiveMap[ChildIndex] = false;

			if (bIsFading)
			{
				HLODState.ForcedVisiblePrimitiveMap[ChildIndex] = true;
			}

			// Fading only occurs at the adjacent hierarchy level, below should be hidden
			if (FLODSceneNode* ChildNode = SceneNodes.Find(Child->PrimitiveComponentId))
			{
				HideNodeChildren(ViewState, *ChildNode);
			}
		}
	}
}

void FLODSceneTree::HideNodeChildren(FSceneViewState* ViewState, FLODSceneNode& Node)
{
	checkSlow(ViewState);
	if (Node.SceneInfo)
	{
		FHLODVisibilityState& HLODState = ViewState->HLODVisibilityState;
		TMap<FPrimitiveComponentId, FHLODSceneNodeVisibilityState>& VisibilityStates = ViewState->HLODSceneNodeVisibilityStates;
		FHLODSceneNodeVisibilityState& NodeVisibility = VisibilityStates.FindOrAdd(Node.SceneInfo->PrimitiveComponentId);

		if (NodeVisibility.UpdateCount != HLODState.UpdateCount)
		{
			NodeVisibility.UpdateCount = HLODState.UpdateCount;

			for (const auto Child : Node.ChildrenSceneInfos)
			{
				if (!Child || !Child->PrimitiveComponentId.IsValid() || !Child->IsIndexValid())
				{
					continue;
				}

				const int32 ChildIndex = Child->GetIndex();

				if (!HLODState.ForcedHiddenPrimitiveMap.IsValidIndex(ChildIndex))
				{
					checkf(0, TEXT("A HLOD Child's PrimitiveSceneInfo PackedIndex was out of ForcedHidden's bounds!"));
					continue;
				}

				HLODState.ForcedHiddenPrimitiveMap[ChildIndex] = true;
				
				// Clear the force visible flag in case the child was processed before it's parent
				HLODState.ForcedVisiblePrimitiveMap[ChildIndex] = false;

				if (FLODSceneNode* ChildNode = SceneNodes.Find(Child->PrimitiveComponentId))
				{
					HideNodeChildren(ViewState, *ChildNode);
				}
			}
		}
	}
}