bool UClassThumbnailRenderer::CanVisualizeAsset(UObject* Object)
{
	if (ThumbnailScene == nullptr)
	{
		ThumbnailScene = new FClassThumbnailScene();
	}

	UClass* Class = Cast<UClass>(Object);

	// Only visualize actor based classes
	if (Class && Class->IsChildOf(AActor::StaticClass()))
	{
		// Try to find any visible primitive components in the class' CDO
		AActor* CDO = Class->GetDefaultObject<AActor>();

		TInlineComponentArray<UActorComponent*> Components;
		CDO->GetComponents(Components);

		for (auto CompIt = Components.CreateConstIterator(); CompIt; ++CompIt)
		{
			if (ThumbnailScene->IsValidComponentForVisualization(*CompIt))
			{
				return true;
			}
		}
	}

	return false;
}

//* Destroys the constructed components.
void AActor::DestroyConstructedComponents()
{
	// Remove all existing components
	TInlineComponentArray<UActorComponent*> PreviouslyAttachedComponents;
	GetComponents(PreviouslyAttachedComponents);

	// We need the hierarchy to be torn down in attachment order, so do a quick sort
	PreviouslyAttachedComponents.Remove(nullptr);
	PreviouslyAttachedComponents.Sort([](UActorComponent& A, UActorComponent& B)
	{
		if (USceneComponent* BSC = Cast<USceneComponent>(&B))
		{
			if (BSC->AttachParent == &A)
			{
				return false;
			}
		}
		return true;
	});

	for (UActorComponent* Component : PreviouslyAttachedComponents)
	{
		if (Component)
		{
			bool bDestroyComponent = false;
			if (Component->IsCreatedByConstructionScript())
			{
				bDestroyComponent = true;
			}
			else
			{
				UActorComponent* OuterComponent = Component->GetTypedOuter<UActorComponent>();
				while (OuterComponent)
				{
					if (OuterComponent->IsCreatedByConstructionScript())
					{
						bDestroyComponent = true;
						break;
					}
					OuterComponent = OuterComponent->GetTypedOuter<UActorComponent>();
				}
			}

			if (bDestroyComponent)
			{
				if (Component == RootComponent)
				{
					RootComponent = NULL;
				}

				Component->DestroyComponent();

				// Rename component to avoid naming conflicts in the case where we rerun the SCS and name the new components the same way.
				FName const NewBaseName( *(FString::Printf(TEXT("TRASH_%s"), *Component->GetClass()->GetName())) );
				FName const NewObjectName = MakeUniqueObjectName(this, GetClass(), NewBaseName);
				Component->Rename(*NewObjectName.ToString(), this, REN_ForceNoResetLoaders|REN_DontCreateRedirectors|REN_NonTransactional);
			}
		}
	}
}

void UUnrealEdEngine::DrawComponentVisualizersHUD(const FViewport* Viewport, const FSceneView* View, FCanvas* Canvas)
{
	// Iterate over all selected actors
	for (FSelectionIterator It(GetSelectedActorIterator()); It; ++It)
	{
		AActor* Actor = Cast<AActor>(*It);
		if (Actor != NULL)
		{
			// Then iterate over components of that actor
			TInlineComponentArray<UActorComponent*> Components;
			Actor->GetComponents(Components);

			for (int32 CompIdx = 0; CompIdx<Components.Num(); CompIdx++)
			{
				UActorComponent* Comp = Components[CompIdx];
				if (Comp->IsRegistered())
				{
					// Try and find a visualizer

					TSharedPtr<FComponentVisualizer> Visualizer = FindComponentVisualizer(Comp->GetClass());
					if (Visualizer.IsValid())
					{
						Visualizer->DrawVisualizationHUD(Comp, Viewport, View, Canvas);
					}
				}
			}
		}
	}
}

USkeleton* FAnimationTrackEditor::AcquireSkeletonFromObjectGuid(const FGuid& Guid)
{
	TArray<UObject*> OutObjects;
	GetSequencer()->GetRuntimeObjects(GetSequencer()->GetFocusedMovieSceneInstance(), Guid, OutObjects);

	USkeleton* Skeleton = NULL;
	for (int32 i = 0; i < OutObjects.Num(); ++i)
	{
		AActor* Actor = Cast<AActor>(OutObjects[i]);

		if (Actor != NULL)
		{
			TInlineComponentArray<USkeletalMeshComponent*> SkeletalMeshComponents;
			Actor->GetComponents(SkeletalMeshComponents);

			for (int32 j = 0; j <SkeletalMeshComponents.Num(); ++j)
			{
				USkeletalMeshComponent* SkeletalMeshComp = SkeletalMeshComponents[j];
				if (SkeletalMeshComp->SkeletalMesh && SkeletalMeshComp->SkeletalMesh->Skeleton)
				{
					// @todo Multiple actors, multiple components
					check(!Skeleton);
					Skeleton = SkeletalMeshComp->SkeletalMesh->Skeleton;
				}
			}
		}
	}

	return Skeleton;
}

void UUnrealEdEngine::SetActorSelectionFlags (AActor* InActor)
{
	TInlineComponentArray<UActorComponent*> Components;
	InActor->GetComponents(Components);

	//for every component in the actor
	for(int32 ComponentIndex = 0; ComponentIndex < Components.Num(); ComponentIndex++)
	{
		UActorComponent* Component = Components[ComponentIndex];
		if (Component->IsRegistered())
		{
			// If we have a 'child actor' component, want to update its visible selection state
			UChildActorComponent* ChildActorComponent = Cast<UChildActorComponent>(Component);
			if(ChildActorComponent != NULL && ChildActorComponent->ChildActor != NULL)
			{
				SetActorSelectionFlags(ChildActorComponent->ChildActor);
			}

			UPrimitiveComponent* PrimComponent = Cast<UPrimitiveComponent>(Component);
			if(PrimComponent != NULL && PrimComponent->IsRegistered())
			{
				PrimComponent->PushSelectionToProxy();
			}

			UDecalComponent* DecalComponent = Cast<UDecalComponent>(Component);
			if(DecalComponent != NULL)// && DecalComponent->IsRegistered())
			{
				DecalComponent->PushSelectionToProxy();
			}
		}
	}
}

void AActor::CheckForErrors()
{
	if ( GetClass()->HasAnyClassFlags(CLASS_Deprecated) )
	{
		FFormatNamedArguments Arguments;
		Arguments.Add(TEXT("ActorName"), FText::FromString(GetName()));
		FMessageLog("MapCheck").Warning()
			->AddToken(FUObjectToken::Create(this))
			->AddToken(FTextToken::Create(FText::Format(LOCTEXT( "MapCheck_Message_ActorIsObselete_Deprecated", "{ActorName} : Obsolete and must be removed! (Class is deprecated)" ), Arguments) ))
			->AddToken(FMapErrorToken::Create(FMapErrors::ActorIsObselete));
		return;
	}
	if ( GetClass()->HasAnyClassFlags(CLASS_Abstract) )
	{
		FFormatNamedArguments Arguments;
		Arguments.Add(TEXT("ActorName"), FText::FromString(GetName()));
		FMessageLog("MapCheck").Warning()
			->AddToken(FUObjectToken::Create(this))
			->AddToken(FTextToken::Create(FText::Format(LOCTEXT( "MapCheck_Message_ActorIsObselete_Abstract", "{ActorName} : Obsolete and must be removed! (Class is abstract)" ), Arguments) ))
			->AddToken(FMapErrorToken::Create(FMapErrors::ActorIsObselete));
		return;
	}

	UPrimitiveComponent* PrimComp = Cast<UPrimitiveComponent>(RootComponent);
	if( PrimComp && (PrimComp->Mobility != EComponentMobility::Movable) && PrimComp->BodyInstance.bSimulatePhysics)
	{
		FFormatNamedArguments Arguments;
		Arguments.Add(TEXT("ActorName"), FText::FromString(GetName()));
		FMessageLog("MapCheck").Warning()
			->AddToken(FUObjectToken::Create(this))
			->AddToken(FTextToken::Create(FText::Format(LOCTEXT( "MapCheck_Message_StaticPhysNone", "{ActorName} : Static object with bSimulatePhysics set to true" ), Arguments) ))
			->AddToken(FMapErrorToken::Create(FMapErrors::StaticPhysNone));
	}

	if( RootComponent && FMath::IsNearlyZero( GetRootComponent()->RelativeScale3D.X * GetRootComponent()->RelativeScale3D.Y * GetRootComponent()->RelativeScale3D.Z ) )
	{
		FFormatNamedArguments Arguments;
		Arguments.Add(TEXT("ActorName"), FText::FromString(GetName()));
		FMessageLog("MapCheck").Error()
			->AddToken(FUObjectToken::Create(this))
			->AddToken(FTextToken::Create(FText::Format(LOCTEXT( "MapCheck_Message_InvalidDrawscale", "{ActorName} : Invalid DrawScale/DrawScale3D" ), Arguments) ))
			->AddToken(FMapErrorToken::Create(FMapErrors::InvalidDrawscale));
	}

	// Route error checking to components.
	TInlineComponentArray<UActorComponent*> Components;
	GetComponents(Components);

	for ( int32 ComponentIndex = 0 ; ComponentIndex < Components.Num() ; ++ComponentIndex )
	{
		UActorComponent* ActorComponent = Components[ ComponentIndex ];
		if (ActorComponent->IsRegistered())
		{
			ActorComponent->CheckForErrors();
		}
	}
}

void FLayers::RemoveViewFromActorViewVisibility( FLevelEditorViewportClient* ViewportClient )
{
	const int32 ViewIndex = ViewportClient->ViewIndex;

	// get the bit for the view index
	uint64 ViewBit = ((uint64)1 << ViewIndex);
	// get all bits under that that we want to keep
	uint64 KeepBits = ViewBit - 1;

	// Iterate over all actors, looking for actors in the specified layers.
	for( FActorIterator It(ViewportClient->GetWorld()) ; It ; ++It )
	{
		const TWeakObjectPtr< AActor > Actor = *It;

		if( !IsActorValidForLayer( Actor ) )
		{
			continue;
		}

		// remember original bits
		uint64 OriginalHiddenViews = Actor->HiddenEditorViews;

		uint64 Was = Actor->HiddenEditorViews;

		// slide all bits higher than ViewIndex down one since the view is being removed from Editor
		uint64 LowBits = Actor->HiddenEditorViews & KeepBits;

		// now slide the top bits down by ViewIndex + 1 (chopping off ViewBit)
		uint64 HighBits = Actor->HiddenEditorViews >> (ViewIndex + 1);
		// then slide back up by ViewIndex, which will now have erased ViewBit, as well as leaving 0 in the low bits
		HighBits = HighBits << ViewIndex;

		// put it all back together
		Actor->HiddenEditorViews = LowBits | HighBits;

		// reregister if we changed the visibility bits, as the rendering thread needs them
		if (OriginalHiddenViews == Actor->HiddenEditorViews)
		{
			continue;
		}

		// Find all registered primitive components and update the scene proxy with the actors updated visibility map
		TInlineComponentArray<UPrimitiveComponent*> Components;
		Actor->GetComponents(Components);

		for( int32 ComponentIdx = 0; ComponentIdx < Components.Num(); ++ComponentIdx )
		{
			UPrimitiveComponent* PrimitiveComponent = Components[ComponentIdx];
			if (PrimitiveComponent->IsRegistered())
			{
				// Push visibility to the render thread
				PrimitiveComponent->PushEditorVisibilityToProxy( Actor->HiddenEditorViews );
			}
		}
	}
}

void FSCSEditorViewportClient::Tick(float DeltaSeconds)
{
	FEditorViewportClient::Tick(DeltaSeconds);

	// Register the selection override delegate for the preview actor's components
	TSharedPtr<SSCSEditor> SCSEditor = BlueprintEditorPtr.Pin()->GetSCSEditor();
	AActor* PreviewActor = GetPreviewActor();
	if (PreviewActor != nullptr)
	{
		TInlineComponentArray<UPrimitiveComponent*> PrimitiveComponents;
		PreviewActor->GetComponents(PrimitiveComponents);

		for (int32 CompIdx = 0; CompIdx < PrimitiveComponents.Num(); ++CompIdx)
		{
			UPrimitiveComponent* PrimComponent = PrimitiveComponents[CompIdx];
			if (!PrimComponent->SelectionOverrideDelegate.IsBound())
			{
				SCSEditor->SetSelectionOverride(PrimComponent);
			}
		}
	}
	else
	{
		InvalidatePreview(false);
	}

	if ( PreviewActor != LastPreviewActor.Get() || PreviewActor == nullptr || IsRealtime() )
	{
		LastPreviewActor = PreviewActor;

		Invalidate();
		RefreshPreviewBounds();
	}

	// Tick the preview scene world.
	if (!GIntraFrameDebuggingGameThread)
	{
		// Ensure that the preview actor instance is up-to-date for component editing (e.g. after compiling the Blueprint, the actor may be reinstanced outside of this class)
		if(PreviewActor != BlueprintEditorPtr.Pin()->GetBlueprintObj()->SimpleConstructionScript->GetComponentEditorActorInstance())
		{
			BlueprintEditorPtr.Pin()->GetBlueprintObj()->SimpleConstructionScript->SetComponentEditorActorInstance(PreviewActor);
		}

		// Allow full tick only if preview simulation is enabled and we're not currently in an active SIE or PIE session
		if(bIsSimulateEnabled && GEditor->PlayWorld == NULL && !GEditor->bIsSimulatingInEditor)
		{
			PreviewScene->GetWorld()->Tick(IsRealtime() ? LEVELTICK_All : LEVELTICK_TimeOnly, DeltaSeconds);
		}
		else
		{
			PreviewScene->GetWorld()->Tick(IsRealtime() ? LEVELTICK_ViewportsOnly : LEVELTICK_TimeOnly, DeltaSeconds);
		}
	}
}

void USceneCaptureComponent::HideActorComponents(AActor* InActor)
{
	if (InActor)
	{
		TInlineComponentArray<UPrimitiveComponent*> PrimitiveComponents;
		InActor->GetComponents(PrimitiveComponents);
		for (int32 ComponentIndex = 0, NumComponents = PrimitiveComponents.Num(); ComponentIndex < NumComponents; ++ComponentIndex)
		{
			HiddenComponents.AddUnique(PrimitiveComponents[ComponentIndex]);
		}
	}
}

void FSCSEditorViewportClient::ProcessClick(class FSceneView& View, class HHitProxy* HitProxy, FKey Key, EInputEvent Event, uint32 HitX, uint32 HitY)
{
	if(HitProxy)
	{
		if(HitProxy->IsA(HInstancedStaticMeshInstance::StaticGetType()))
		{
			HInstancedStaticMeshInstance* InstancedStaticMeshInstanceProxy = ( ( HInstancedStaticMeshInstance* )HitProxy );

			TSharedPtr<ISCSEditorCustomization> Customization = BlueprintEditorPtr.Pin()->CustomizeSCSEditor(InstancedStaticMeshInstanceProxy->Component);
			if(Customization.IsValid() && Customization->HandleViewportClick(AsShared(), View, HitProxy, Key, Event, HitX, HitY))
			{
				Invalidate();
			}
		}
		else if(HitProxy->IsA(HActor::StaticGetType()))
		{
			HActor* ActorProxy = (HActor*)HitProxy;
			AActor* PreviewActor = GetPreviewActor();
			if(ActorProxy && ActorProxy->Actor && ActorProxy->Actor == PreviewActor && ActorProxy->PrimComponent != NULL)
			{
				TInlineComponentArray<USceneComponent*> SceneComponents;
				ActorProxy->Actor->GetComponents(SceneComponents);
	
				for(auto CompIt = SceneComponents.CreateConstIterator(); CompIt; ++CompIt)
				{
					USceneComponent* CompInstance = *CompIt;
					TSharedPtr<ISCSEditorCustomization> Customization = BlueprintEditorPtr.Pin()->CustomizeSCSEditor(CompInstance);
					if (Customization.IsValid() && Customization->HandleViewportClick(AsShared(), View, HitProxy, Key, Event, HitX, HitY))
					{
						break;
					}

					if (CompInstance == ActorProxy->PrimComponent)
					{
						const bool bIsCtrlKeyDown = Viewport->KeyState(EKeys::LeftControl) || Viewport->KeyState(EKeys::RightControl);
						if (BlueprintEditorPtr.IsValid())
						{
							// Note: This will find and select any node associated with the component instance that's attached to the proxy (including visualizers)
							BlueprintEditorPtr.Pin()->FindAndSelectSCSEditorTreeNode(CompInstance, bIsCtrlKeyDown);
						}
						break;
					}
				}
			}

			Invalidate();
		}

		// Pass to component vis manager
		//GUnrealEd->ComponentVisManager.HandleProxyForComponentVis(HitProxy);
	}
}

	static UProperty *GetPropertyByName( UClass *InClass, const FName &Name )
	{
		if ( InClass == NULL )
			return NULL;

		UProperty *Property = GetPropertyByNameRecurse( InClass, Name.ToString() );
		if ( Property != NULL )
		{
			return Property;
		}

		AActor *AsActor = Cast<AActor>(InClass->ClassDefaultObject);
		if ( AsActor != NULL )
		{
			FString ComponentPropertyName = Name.ToString();
			int32 SplitIndex = 0;
			if ( ComponentPropertyName.FindChar( '.', SplitIndex ) )
			{
				//FString ComponentName = ComponentPropertyName.LeftChop(SplitIndex);
				ComponentPropertyName = ComponentPropertyName.RightChop(SplitIndex+1);

				TInlineComponentArray<UActorComponent*> ActorComponents;
				AsActor->GetComponents(ActorComponents);
				for ( auto ComponentIt = ActorComponents.CreateIterator(); ComponentIt; ++ComponentIt )
				{
					UActorComponent *Component = *ComponentIt;
					check( Component != NULL );
					/*
					if ( Component->GetName() != ComponentName )
					{
						continue;
					}
					*/

					Property = GetPropertyByNameRecurse( Component->GetClass(), ComponentPropertyName );
					if ( Property != NULL )
					{
						return Property;
					}
				}
			}
		}

		return NULL;
	}

/**
* Determines if the provided actor is capable of having a material applied to it.
*
* @param	TargetActor	Actor to check for the validity of material application
*
* @return	true if the actor is valid for material application; false otherwise
*/
bool FActorFactoryAssetProxy::IsActorValidForMaterialApplication( AActor* TargetActor )
{
	bool bIsValid = false;

	//@TODO: PAPER2D: Extend this to support non mesh components (or make sprites a mesh component)

	// Check if the actor has a mesh or fog volume density. If so, it can likely have
	// a material applied to it. Otherwise, it cannot.
	if ( TargetActor )
	{
		TInlineComponentArray<UMeshComponent*> MeshComponents;
		TargetActor->GetComponents(MeshComponents);

		bIsValid = (MeshComponents.Num() > 0);
	}

	return bIsValid;
}

void UUnrealEdEngine::SelectComponent(UActorComponent* Component, bool bInSelected, bool bNotify, bool bSelectEvenIfHidden)
{
	// Don't do any work if the component's selection state matches the target selection state
	const bool bComponentSelected = GetSelectedComponents()->IsSelected(Component);
	if (( bComponentSelected && !bInSelected ) || ( !bComponentSelected && bInSelected ))
	{
		if (bInSelected)
		{
			UE_LOG(LogEditorSelectUtils, Verbose, TEXT("Selected Component: %s"), *Component->GetClass()->GetName());
		}
		else
		{
			UE_LOG(LogEditorSelectUtils, Verbose, TEXT("Deselected Component: %s"), *Component->GetClass()->GetName());
		}

		GetSelectedComponents()->Select(Component, bInSelected);

		// Make sure the override delegate is bound properly
		auto SceneComponent = Cast<USceneComponent>(Component);
		if (SceneComponent)
		{
			FComponentEditorUtils::BindComponentSelectionOverride(SceneComponent, true);
		}

		// Update the selection visualization
		AActor* ComponentOwner = Component->GetOwner();
		if (ComponentOwner != nullptr)
		{
			TInlineComponentArray<UPrimitiveComponent*> PrimitiveComponents;
			ComponentOwner->GetComponents(PrimitiveComponents);

			for (int32 Idx = 0; Idx < PrimitiveComponents.Num(); ++Idx)
			{
				PrimitiveComponents[Idx]->PushSelectionToProxy();
			}
		}

		if (bNotify)
		{
			NoteSelectionChange();
		}
	}
}

void UActorRecording::ProcessNewComponentArray(TInlineComponentArray<USceneComponent*>& ProspectiveComponents) const
{
	// Only iterate as far as the current size of the array (it may grow inside the loop)
	int32 LastIndex = ProspectiveComponents.Num();
	for(int32 Index = 0; Index < LastIndex; ++Index)
	{
		USceneComponent* NewComponent = ProspectiveComponents[Index];

		USceneComponent* Parent = ProspectiveComponents[Index]->GetAttachParent();

		while (Parent)
		{
			TWeakObjectPtr<USceneComponent> WeakParent(Parent);
			if (TrackedComponents.Contains(WeakParent) || ProspectiveComponents.Contains(Parent) || Parent->GetOwner() != NewComponent->GetOwner())
			{
				break;
			}
			else
			{
				ProspectiveComponents.Add(Parent);
			}

			Parent = Parent->GetAttachParent();
		}
	}

	// Sort parent first, to ensure that attachments get added properly
	TMap<USceneComponent*, int32> AttachmentDepths;
	for (USceneComponent* Component : ProspectiveComponents)
	{
		AttachmentDepths.Add(Component, GetAttachmentDepth(Component));
	}

	ProspectiveComponents.Sort(
		[&](USceneComponent& A, USceneComponent& B)
		{
			return *AttachmentDepths.Find(&A) < *AttachmentDepths.Find(&B);
		}
	);
}

static void DrawSnapVertices( AActor* Actor, float PointSize, FPrimitiveDrawInterface* PDI )
{
	TInlineComponentArray<UActorComponent*> Components;
	Actor->GetComponents(Components);

	// Get the closest vertex on each component
	for( int32 ComponentIndex  = 0; ComponentIndex < Components.Num(); ++ComponentIndex )
	{
		TSharedPtr<FVertexIterator> VertexGetter = MakeVertexIterator( Cast<UPrimitiveComponent>( Components[ComponentIndex] ) );
		if( VertexGetter.IsValid() )
		{
			FVertexIterator& VertexGetterRef = *VertexGetter;
			for( ; VertexGetterRef; ++VertexGetterRef )
			{
				PDI->DrawPoint( VertexGetterRef.Position(), VertexSnappingConstants::VertexHelperColor, PointSize, SDPG_World );
			}
		}
		else
		{
			PDI->DrawPoint( Actor->GetActorLocation(), VertexSnappingConstants::VertexHelperColor, PointSize, SDPG_World );
		}
	}
}

	static UProperty *GetPropertyByName( UObject *Target, UStruct *InStruct, const FString &PropertyName, void ** hContainerPtr, int32 &OutArrayIndex )
	{
		UProperty *Prop = GetPropertyByNameRecurse( Target->GetClass(), PropertyName, hContainerPtr, OutArrayIndex );
		if ( Prop == NULL )
		{
			AActor *AsActor = Cast<AActor>(Target);
			if ( AsActor != NULL )
			{
				FString ComponentPropertyName = PropertyName;
				int32 SplitIndex = 0;
				if ( ComponentPropertyName.FindChar( '.', SplitIndex ) )
				{
					//FString ComponentName = ComponentPropertyName.LeftChop(SplitIndex);
					ComponentPropertyName = ComponentPropertyName.RightChop(SplitIndex+1);

					TInlineComponentArray<UActorComponent*> ActorComponents;
					AsActor->GetComponents(ActorComponents);
					for ( auto ComponentIt = ActorComponents.CreateIterator(); ComponentIt && !Prop; ++ComponentIt )
					{
						UActorComponent *Component = *ComponentIt;
						check( Component != NULL );
						/*
						if ( Component->GetName() != ComponentName )
						{
							continue;
						}
						*/

						*hContainerPtr = Component;
						Prop = GetPropertyByNameRecurse( Component->GetClass(), ComponentPropertyName, hContainerPtr, OutArrayIndex );
					}
				}
			}
		}

		return Prop;
	}

FSnappingVertex FVertexSnappingImpl::GetClosestVertex( const TArray<FSnapActor>& Actors, const FVertexSnappingArgs& InArgs )
{
	// The current closest distance
	float ClosestDistance = FLT_MAX;

	const FPlane& ActorPlane = InArgs.ActorPlane;
	EAxisList::Type CurrentAxis = InArgs.CurrentAxis;
	const FSceneView* View = InArgs.SceneView;
	const FVector& CurrentLocation = InArgs.CurrentLocation;
	const FVector2D& MousePosition = InArgs.MousePosition;

	FSnappingVertex ClosestLocation( CurrentLocation );

	AActor* ClosestActor = NULL;
	// Find the closest vertex on each actor and then from that list find the closest vertex
	for( int32 ActorIndex = 0; ActorIndex < Actors.Num(); ++ActorIndex )
	{
		const FSnapActor& SnapActor = Actors[ActorIndex];
		AActor* Actor = SnapActor.Actor;

		// Get the closest vertex on each component
		TInlineComponentArray<UPrimitiveComponent*> PrimitiveComponents;
		Actor->GetComponents(PrimitiveComponents);

		for( int32 ComponentIndex  = 0; ComponentIndex < PrimitiveComponents.Num(); ++ComponentIndex )
		{
			FSnappingVertex ClosestLocationOnComponent( CurrentLocation );
			if( !GetClosestVertexOnComponent( SnapActor, PrimitiveComponents[ComponentIndex], InArgs, ClosestLocationOnComponent ) )
			{
				ClosestLocationOnComponent.Position = Actor->GetActorLocation();
				ClosestLocationOnComponent.Normal = FVector::ZeroVector;
			}

			float Distance = 0;
			if( CurrentAxis != EAxisList::Screen )
			{
				// Compute the distance from the point being snapped.  When not in screen space we snap to the plane created by the current closest vertex
				Distance = ActorPlane.PlaneDot( ClosestLocationOnComponent.Position );
			}
			else
			{
				// Favor the vertex closest to the mouse in screen space
				FVector2D ComponentLocPixel;
				if( View->WorldToPixel( ClosestLocationOnComponent.Position, ComponentLocPixel ) )
				{
					Distance = FVector::DistSquared( FVector( MousePosition, 0 ), FVector( ComponentLocPixel, 0 ) );
				}
			}

			if( 
				// A close vertex must have been found
				ClosestLocationOnComponent.Position != CurrentLocation 
				// we must have made some movement
				&& !FMath::IsNearlyZero(Distance) 
				// If not in screen space the vertex cannot be behind the point being snapped
				&& ( CurrentAxis == EAxisList::Screen || !FMath::IsNegativeFloat( Distance ) )
				// The vertex must be closer than the current closest vertex
				&& Distance < ClosestDistance )
			{
				ClosestActor = Actor;
				ClosestDistance = Distance;
				ClosestLocation = ClosestLocationOnComponent;
			}
		}
	}

	if( InArgs.bDrawVertexHelpers )
	{
		if(ActorVertsToDraw.IsValid())
		{
			ActorVertsToFade.Add(ActorVertsToDraw, FApp::GetCurrentTime());
		}

		ActorVertsToFade.Remove(ClosestActor);
		ActorVertsToDraw = ClosestActor;
	}
	else
	{
		ActorVertsToDraw = nullptr;
		ActorVertsToFade.Empty();
	}


	return ClosestLocation;
}

void UActorRecording::StartRecordingNewComponents(ULevelSequence* CurrentSequence, float CurrentSequenceTime)
{
	if (GetActorToRecord() != nullptr)
	{
		// find the new component(s)
		TInlineComponentArray<USceneComponent*> NewComponents;
		TArray<USceneComponent*> SceneComponents;
		GetSceneComponents(SceneComponents);
		for(USceneComponent* SceneComponent : SceneComponents)
		{
			if(ValidComponent(SceneComponent))
			{
				TWeakObjectPtr<USceneComponent> WeakSceneComponent(SceneComponent);
				int32 FoundIndex = TrackedComponents.Find(WeakSceneComponent);
				if(FoundIndex == INDEX_NONE)
				{
					// new component!
					NewComponents.Add(SceneComponent);
				}
			}
		}

		ProcessNewComponentArray(NewComponents);

		UMovieScene* MovieScene = CurrentSequence->GetMovieScene();
		check(MovieScene);

		FAnimationRecordingSettings ComponentAnimationSettings = AnimationSettings;
		ComponentAnimationSettings.bRemoveRootAnimation = false;
		ComponentAnimationSettings.bRecordInWorldSpace = false;

		const USequenceRecorderSettings* Settings = GetDefault<USequenceRecorderSettings>();
		if (!bRecordToPossessable)
		{
			FMovieSceneSpawnable* Spawnable = MovieScene->FindSpawnable(Guid);
			check(Spawnable);

			AActor* ObjectTemplate = CastChecked<AActor>(Spawnable->GetObjectTemplate());

			for (USceneComponent* SceneComponent : NewComponents)
			{
				// new component, so we need to add this to our BP if it didn't come from SCS
				FName NewName;
				if (SceneComponent->CreationMethod != EComponentCreationMethod::SimpleConstructionScript)
				{
					// Give this component a unique name within its parent
					NewName = *FString::Printf(TEXT("Dynamic%s"), *SceneComponent->GetFName().GetPlainNameString());
					NewName.SetNumber(1);
					while (FindObjectFast<UObject>(ObjectTemplate, NewName))
					{
						NewName.SetNumber(NewName.GetNumber() + 1);
					}

					USceneComponent* TemplateRoot = ObjectTemplate->GetRootComponent();
					USceneComponent* AttachToComponent = nullptr;

					// look for a similar attach parent in the current structure
					USceneComponent* AttachParent = SceneComponent->GetAttachParent();
					if(AttachParent != nullptr)
					{
						// First off, check if we're attached to a component that has already been duplicated into this object
						// If so, the name lookup will fail, so we use a direct reference
						if (TWeakObjectPtr<USceneComponent>* DuplicatedComponent = DuplicatedDynamicComponents.Find(AttachParent))
						{
							AttachToComponent = DuplicatedComponent->Get();
						}
					
						// If we don't have an attachment parent duplicated already, perform a name lookup
						if (!AttachToComponent)
						{
							FName AttachName = SceneComponent->GetAttachParent()->GetFName();

							TInlineComponentArray<USceneComponent*> AllChildren;
							ObjectTemplate->GetComponents(AllChildren);

							for (USceneComponent* Child : AllChildren)
							{
								CA_SUPPRESS(28182); // Dereferencing NULL pointer. 'Child' contains the same NULL value as 'AttachToComponent' did.
								if (Child->GetFName() == AttachName)
								{
									AttachToComponent = Child;
									break;
								}
							}
						}
					}

					if (!AttachToComponent)
					{
						AttachToComponent = ObjectTemplate->GetRootComponent();
					}

					USceneComponent* NewTemplateComponent = Cast<USceneComponent>(StaticDuplicateObject(SceneComponent, ObjectTemplate, NewName, RF_AllFlags & ~RF_Transient));
					NewTemplateComponent->AttachToComponent(AttachToComponent, FAttachmentTransformRules::KeepRelativeTransform, SceneComponent->GetAttachSocketName());

					ObjectTemplate->AddInstanceComponent(NewTemplateComponent);

					DuplicatedDynamicComponents.Add(SceneComponent, NewTemplateComponent);
				}
				else
//.........这里部分代码省略.........

bool UMatineeTrackAnimControlHelper::PreCreateKeyframe( UInterpTrack *Track, float fTime ) const
{
	KeyframeAddAnimSequence = NULL;
	UInterpTrackAnimControl	*AnimTrack = CastChecked<UInterpTrackAnimControl>(Track);
	UInterpGroup* Group = CastChecked<UInterpGroup>(Track->GetOuter());

	AActor* Actor = GetGroupActor(Track);
	if (!Actor)
	{
		// error message
		UE_LOG(LogSlateMatinee, Warning, TEXT("No Actor is selected. Select actor first."));
		return false;
	}

	USkeletalMeshComponent * SkelMeshComp = NULL;

	TInlineComponentArray<USkeletalMeshComponent*> SkeletalMeshComponents;
	Actor->GetComponents(SkeletalMeshComponents);

	for (int32 I=0; I<SkeletalMeshComponents.Num(); ++I)
	{
		USkeletalMeshComponent * CurSkelMeshComp = SkeletalMeshComponents[I];
		// if qualified to play animation, break
		if (CurSkelMeshComp->SkeletalMesh && CurSkelMeshComp->SkeletalMesh->Skeleton)
		{
			SkelMeshComp = CurSkelMeshComp;
			break;
		}
	}

	if (!SkelMeshComp)
	{
		UE_LOG(LogSlateMatinee, Warning, TEXT("SkeletalMeshComponent isn't found in the selected actor or it does not have Mesh/Skeleton set up in order to play animation"));
		return false;
	}

	USkeleton* Skeleton = SkelMeshComp->SkeletalMesh->Skeleton;
	if ( Skeleton )
	{
		// Show the dialog.
		FEdModeInterpEdit* Mode = (FEdModeInterpEdit*)GLevelEditorModeTools().GetActiveMode( FBuiltinEditorModes::EM_InterpEdit );
		check(Mode != NULL);
		check(Mode->InterpEd != NULL);
		
		TSharedPtr< SWindow > Parent = FSlateApplication::Get().GetActiveTopLevelWindow();
		if ( Parent.IsValid() )
		{
			FAssetPickerConfig AssetPickerConfig;
			AssetPickerConfig.OnAssetSelected = FOnAssetSelected::CreateUObject( this, &UMatineeTrackAnimControlHelper::OnAddKeyTextEntry, Mode->InterpEd, Track );
			AssetPickerConfig.bAllowNullSelection = false;
			AssetPickerConfig.InitialAssetViewType = EAssetViewType::List;

			// Filter config
			AssetPickerConfig.Filter.ClassNames.Add(UAnimSequence::StaticClass()->GetFName());
			AssetPickerConfig.Filter.TagsAndValues.Add(TEXT("Skeleton"), FAssetData(Skeleton).GetExportTextName());

			FContentBrowserModule& ContentBrowserModule = FModuleManager::Get().LoadModuleChecked<FContentBrowserModule>(TEXT("ContentBrowser"));

			FMenuBuilder MenuBuilder(true, NULL);
			MenuBuilder.BeginSection(NAME_None, LOCTEXT("MatineeAnimPicker", "Browse"));
			{
				TSharedPtr<SBox> MenuEntry = SNew(SBox)
				.WidthOverride(300.0f)
				.HeightOverride(300.f)
				[
					ContentBrowserModule.Get().CreateAssetPicker(AssetPickerConfig)
				];
				MenuBuilder.AddWidget(MenuEntry.ToSharedRef(), FText::GetEmpty(), true);
			}
			MenuBuilder.EndSection();

			EntryMenu = FSlateApplication::Get().PushMenu(
				Parent.ToSharedRef(),
				FWidgetPath(),
				MenuBuilder.MakeWidget(),
				FSlateApplication::Get().GetCursorPos(),
				FPopupTransitionEffect(FPopupTransitionEffect::TypeInPopup)
				);
		}
	}
	else
	{
		FMessageDialog::Open( EAppMsgType::Ok, NSLOCTEXT("UnrealEd", "NoAnimSeqsFound", "No AnimSequences Found. Make sure to load AnimSequences.") );
	}

	return false;
}

void UUnrealEdEngine::UpdateVolumeActorVisibility( UClass* InVolumeActorClass, FLevelEditorViewportClient* InViewport )
{
	TSubclassOf<AActor> VolumeClassToCheck = InVolumeActorClass ? InVolumeActorClass : AVolume::StaticClass();
	
	// Build a list of actors that need to be updated.  Only take actors of the passed in volume class.  
	UWorld* World = InViewport ? InViewport->GetWorld() : GWorld;
	TArray< AActor *> ActorsToUpdate;
	for( TActorIterator<AActor> It( World, VolumeClassToCheck ); It; ++It)
	{
		ActorsToUpdate.Add(*It);
	}

	if( ActorsToUpdate.Num() > 0 )
	{
		TArray< AActor* > ActorsThatChanged;
		if( !InViewport )
		{
			// Update the visibility state of each actor for each viewport
			for( int32 ViewportIdx = 0; ViewportIdx < LevelViewportClients.Num(); ++ViewportIdx )
			{
				FLevelEditorViewportClient& ViewClient = *LevelViewportClients[ViewportIdx];
				{
					// Only update the editor frame clients as those are the only viewports right now that show volumes.
					InternalUpdateVolumeActorVisibility( ActorsToUpdate, ViewClient, ActorsThatChanged );
					if( ActorsThatChanged.Num() )
					{
						// If actor visibility changed in the viewport, it needs to be redrawn
						ViewClient.Invalidate();
					}
				}
			}
		}
		else
		{
			// Only update the editor frame clients as those are the only viewports right now that show volumes.
			InternalUpdateVolumeActorVisibility( ActorsToUpdate, *InViewport, ActorsThatChanged );
			if( ActorsThatChanged.Num() )
			{	
				// If actor visibility changed in the viewport, it needs to be redrawn
				InViewport->Invalidate();
			}
		}

		// Push all changes in the actors to the scene proxy so the render thread correctly updates visibility
		for( int32 ActorIdx = 0; ActorIdx < ActorsThatChanged.Num(); ++ActorIdx )
		{
			AActor* ActorToUpdate = ActorsThatChanged[ ActorIdx ];

			// Find all registered primitive components and update the scene proxy with the actors updated visibility map
			TInlineComponentArray<UPrimitiveComponent*> PrimitiveComponents;
			ActorToUpdate->GetComponents(PrimitiveComponents);

			for( int32 ComponentIdx = 0; ComponentIdx < PrimitiveComponents.Num(); ++ComponentIdx )
			{
				UPrimitiveComponent* PrimitiveComponent = PrimitiveComponents[ComponentIdx];
				if (PrimitiveComponent->IsRegistered())
				{
					// Push visibility to the render thread
					PrimitiveComponent->PushEditorVisibilityToProxy( ActorToUpdate->HiddenEditorViews );
				}
			}
		}
	}
}