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

#include "PhysicsAssetEditorSharedData.h"
#include "PhysicsAssetEditorPhysicsHandleComponent.h"
#include "PhysicsAssetRenderUtils.h"
#include "PhysicsEngine/RigidBodyIndexPair.h"
#include "Misc/MessageDialog.h"
#include "Modules/ModuleManager.h"
#include "UObject/UObjectIterator.h"
#include "Widgets/SWindow.h"
#include "Components/StaticMeshComponent.h"
#include "Engine/SkeletalMesh.h"
#include "Components/SkeletalMeshComponent.h"
#include "Preferences/PhysicsAssetEditorOptions.h"
#include "Engine/StaticMesh.h"
#include "Engine/CollisionProfile.h"
#include "Editor.h"
#include "PhysicsAssetEditorModule.h"
#include "EditorSupportDelegates.h"
#include "ScopedTransaction.h"
#include "PhysicsAssetEditorSkeletalMeshComponent.h"
#include "MeshUtilities.h"
#include "MeshUtilitiesCommon.h"
#include "PhysicsEngine/BoxElem.h"
#include "PhysicsEngine/ConstraintInstance.h"
#include "PhysicsEngine/PhysicsConstraintTemplate.h"
#include "PhysicsEngine/PhysicalAnimationComponent.h"
#include "PhysicsEngine/PhysicsAsset.h"
#include "PhysicsAssetEditorAnimInstance.h"
#include "IPersonaPreviewScene.h"
#include "PhysicsPublic.h"
#include "PhysicsAssetGenerationSettings.h"
#include "IDetailsView.h"
#include "PropertyEditorModule.h"
#include "Widgets/Input/SButton.h"
#include "Widgets/Text/STextBlock.h"
#include "ClothingSimulationInteractor.h"
#include "UnrealExporter.h"
#include "Exporters/Exporter.h"
#include "Factories.h"
#include "HAL/PlatformApplicationMisc.h"
#include "SPrimaryButton.h"

#define LOCTEXT_NAMESPACE "PhysicsAssetEditorShared"

//PRAGMA_DISABLE_OPTIMIZATION

namespace SharedDataConstants
{
	const FString ConstraintType = TEXT("Constraint");
	const FString BodyType = TEXT("SkeletalBodySetup");
}


FScopedBulkSelection::FScopedBulkSelection(TSharedPtr<FPhysicsAssetEditorSharedData> InSharedData)
	: SharedData(InSharedData)
{
	SharedData->bSuspendSelectionBroadcast = true;
}

FScopedBulkSelection::~FScopedBulkSelection()
{
	SharedData->bSuspendSelectionBroadcast = false;
	SharedData->BroadcastSelectionChanged();
}

FPhysicsAssetEditorSharedData::FPhysicsAssetEditorSharedData()
	: COMRenderColor(255,255,100)
	, bSuspendSelectionBroadcast(false)
	, InsideSelChange(0)
{
	// Editor variables
	bShowCOM = false;

	bRunningSimulation = false;
	bNoGravitySimulation = false;

	bManipulating = false;

	LastClickPos = FIntPoint::ZeroValue;
	LastClickOrigin = FVector::ZeroVector;
	LastClickDirection = FVector::UpVector;
	LastClickHitPos = FVector::ZeroVector;
	LastClickHitNormal = FVector::UpVector;
	bLastClickHit = false;
	
	// Construct mouse handle
	MouseHandle = NewObject<UPhysicsAssetEditorPhysicsHandleComponent>();

	// Construct sim options.
	EditorOptions = NewObject<UPhysicsAssetEditorOptions>(GetTransientPackage(), MakeUniqueObjectName(GetTransientPackage(), UPhysicsAssetEditorOptions::StaticClass(), FName(TEXT("EditorOptions"))), RF_Transactional);
	check(EditorOptions);

	EditorOptions->LoadConfig();
}

FPhysicsAssetEditorSharedData::~FPhysicsAssetEditorSharedData()
{

}

void FPhysicsAssetEditorSharedData::Initialize(const TSharedRef<IPersonaPreviewScene>& InPreviewScene)
{
	PreviewScene = InPreviewScene;

	EditorSkelComp = nullptr;
	PhysicalAnimationComponent = nullptr;
	FSoftObjectPath PreviewMeshStringRef = PhysicsAsset->PreviewSkeletalMesh.ToSoftObjectPath();

	// Look for body setups with no shapes (how does this happen?).
	// If we find one- just bang on a default box.
	bool bFoundEmptyShape = false;
	for (int32 i = 0; i <PhysicsAsset->SkeletalBodySetups.Num(); ++i)
	{
		UBodySetup* BodySetup = PhysicsAsset->SkeletalBodySetups[i];
		if (BodySetup && BodySetup->AggGeom.GetElementCount() == 0)
		{
			FKBoxElem BoxElem;
			BoxElem.SetTransform(FTransform::Identity);
			BoxElem.X = 15.f;
			BoxElem.Y = 15.f;
			BoxElem.Z = 15.f;
			BodySetup->AggGeom.BoxElems.Add(BoxElem);
			check(BodySetup->AggGeom.BoxElems.Num() == 1);

			bFoundEmptyShape = true;
		}
	}

	// Pop up a warning about what we did.
	if (bFoundEmptyShape)
	{
		FMessageDialog::Open(EAppMsgType::Ok, NSLOCTEXT("UnrealEd", "EmptyBodyFound", "Bodies was found with no primitives!\nThey have been reset to have a box."));
	}

	IMeshUtilities& MeshUtilities = FModuleManager::Get().LoadModuleChecked<IMeshUtilities>("MeshUtilities");
	// Used for viewing bone influences, resetting bone geometry etc.
	USkeletalMesh* EditorSkelMesh = PhysicsAsset->GetPreviewMesh();
	if(EditorSkelMesh)
	{
		MeshUtilities.CalcBoneVertInfos(EditorSkelMesh, DominantWeightBoneInfos, true);
		MeshUtilities.CalcBoneVertInfos(EditorSkelMesh, AnyWeightBoneInfos, false);

		// Ensure PhysicsAsset mass properties are up to date.
		PhysicsAsset->UpdateBoundsBodiesArray();

		// Check if there are any bodies in the Asset which do not have bones in the skeletal mesh.
		// If so, put up a warning.
		TArray<int32> MissingBodyIndices;
		FString BoneNames;
		for (int32 i = 0; i <PhysicsAsset->SkeletalBodySetups.Num(); ++i)
		{
			if (!ensure(PhysicsAsset->SkeletalBodySetups[i]))
			{
				continue;
			}
			FName BoneName = PhysicsAsset->SkeletalBodySetups[i]->BoneName;
			int32 BoneIndex = EditorSkelMesh->GetRefSkeleton().FindBoneIndex(BoneName);
			if (BoneIndex == INDEX_NONE)
			{
				MissingBodyIndices.Add( i );
				BoneNames += FString::Printf(TEXT("\t%s\n"), *BoneName.ToString());
			}
		}

		const FText MissingBodyMsg = FText::Format( LOCTEXT( "MissingBones", "The following Bodies are in the PhysicsAsset, but have no corresponding bones in the SkeletalMesh.\nClick OK to delete them, or Cancel to ignore.\n\n{0}" ), FText::FromString( BoneNames ) );

		if ( MissingBodyIndices.Num() )
		{
			if ( FMessageDialog::Open( EAppMsgType::OkCancel, MissingBodyMsg ) == EAppReturnType::Ok )
			{
				// Delete the bodies with no associated bones

				const FScopedTransaction Transaction( LOCTEXT( "DeleteUnusedPhysicsBodies", "Delete Physics Bodies With No Bones" ) );
				PhysicsAsset->SetFlags(RF_Transactional);
				PhysicsAsset->Modify();

				// Iterate backwards, as PhysicsAsset->SkeletalBodySetups is a TArray and Unreal containers don't support remove_if()
				for ( int32 i = MissingBodyIndices.Num() - 1; i >= 0; --i )
				{
					DeleteBody( MissingBodyIndices[i], false );
				}
			}
		}
	}

	// Support undo/redo
	PhysicsAsset->SetFlags(RF_Transactional);

	ClearSelectedBody();
	ClearSelectedConstraints();
}

void FPhysicsAssetEditorSharedData::BroadcastSelectionChanged()
{
	if (!bSuspendSelectionBroadcast)
	{
		SelectionChangedEvent.Broadcast(SelectedBodies, SelectedConstraints);
	}
}

void FPhysicsAssetEditorSharedData::BroadcastHierarchyChanged()
{
	HierarchyChangedEvent.Broadcast();
}

void FPhysicsAssetEditorSharedData::BroadcastPreviewChanged()
{
	PreviewChangedEvent.Broadcast();
}

void FPhysicsAssetEditorSharedData::CachePreviewMesh()
{
	USkeletalMesh* PreviewMesh = PhysicsAsset->PreviewSkeletalMesh.LoadSynchronous();

	if (PreviewMesh == nullptr)
	{
		// Fall back to the default skeletal mesh in the EngineMeshes package.
		// This is statically loaded as the package is likely not fully loaded
		// (otherwise, it would have been found in the above iteration).
		PreviewMesh = (USkeletalMesh*)StaticLoadObject(USkeletalMesh::StaticClass(), NULL, TEXT("/Engine/EngineMeshes/SkeletalCube.SkeletalCube"), NULL, LOAD_None, NULL);
		check(PreviewMesh);

		PhysicsAsset->PreviewSkeletalMesh = PreviewMesh;

		FMessageDialog::Open(EAppMsgType::Ok, FText::Format(
				LOCTEXT("Error_PhysicsAssetHasNoSkelMesh", "Warning: Physics Asset has no skeletal mesh assigned.\nFor now, a simple default skeletal mesh ({0}) will be used.\nYou can fix this by opening the asset and choosing another skeletal mesh from the toolbar."),
				FText::FromString(PreviewMesh->GetFullName())));
	}
	else if(PreviewMesh->GetSkeleton() == nullptr)
	{
		// Fall back in the case of a deleted skeleton
		PreviewMesh = (USkeletalMesh*)StaticLoadObject(USkeletalMesh::StaticClass(), NULL, TEXT("/Engine/EngineMeshes/SkeletalCube.SkeletalCube"), NULL, LOAD_None, NULL);
		check(PreviewMesh);

		PhysicsAsset->PreviewSkeletalMesh = PreviewMesh;

		FMessageDialog::Open(EAppMsgType::Ok, FText::Format(
				LOCTEXT("Error_PhysicsAssetHasNoSkelMeshSkeleton", "Warning: Physics Asset has a skeletal mesh with no skeleton assigned.\nFor now, a simple default skeletal mesh ({0}) will be used.\nYou can fix this by opening the asset and choosing another skeletal mesh from the toolbar, or repairing the skeleton."),
				FText::FromString(PreviewMesh->GetFullName())));
	}
}

void FPhysicsAssetEditorSharedData::CopyConstraintProperties(const UPhysicsConstraintTemplate * FromConstraintSetup, UPhysicsConstraintTemplate * ToConstraintSetup, bool bKeepOldRotation)
{
	ToConstraintSetup->Modify();
	FConstraintInstance OldInstance = ToConstraintSetup->DefaultInstance;
	ToConstraintSetup->DefaultInstance.CopyConstraintPhysicalPropertiesFrom(&FromConstraintSetup->DefaultInstance, /*bKeepPosition=*/true, bKeepOldRotation);
	ToConstraintSetup->UpdateProfileInstance();
}

void FPhysicsAssetEditorSharedData::CopyToClipboard(const FString& ObjectType, UObject* Object)
{
	FSoftObjectPath PhysicsAssetPath(PhysicsAsset);
	FSoftObjectPath ObjectAssetPath(Object);
	FString ClipboardContent = FString::Format(TEXT("{0};{1};{2}"), { PhysicsAssetPath.ToString(), *ObjectType, ObjectAssetPath.ToString() });
	FPlatformApplicationMisc::ClipboardCopy(*ClipboardContent);
}

bool FPhysicsAssetEditorSharedData::PasteFromClipboard(const FString& InObjectType, UPhysicsAsset*& OutAsset, UObject*& OutObject)
{
	FString SourceObjectType;
	return ParseClipboard(OutAsset, SourceObjectType, OutObject) && SourceObjectType == InObjectType;
}

void FPhysicsAssetEditorSharedData::ConditionalClearClipboard(const FString& ObjectType, UObject* Object)
{
	UPhysicsAsset* SourceAsset = nullptr;
	FString SourceObjectType;
	UObject* SourceObject = nullptr;

	if(ParseClipboard(SourceAsset, SourceObjectType, SourceObject))
	{
		// Clear the clipboard if it matches the parameters we're given
		if (SourceAsset == PhysicsAsset && SourceObjectType == ObjectType && SourceObject == Object)
		{
			FString EmptyString;
			FPlatformApplicationMisc::ClipboardCopy(*EmptyString);
		}
	}
}

bool FPhysicsAssetEditorSharedData::ClipboardHasCompatibleData()
{
	UPhysicsAsset* DummyAsset = nullptr;
	FString DummyObjectType;
	UObject* DummyObject = nullptr;
	return ParseClipboard(DummyAsset, DummyObjectType, DummyObject);
}

bool FPhysicsAssetEditorSharedData::ParseClipboard(UPhysicsAsset*& OutAsset, FString& OutObjectType, UObject*& OutObject)
{
	FString ClipboardContent;
	FPlatformApplicationMisc::ClipboardPaste(ClipboardContent);

	TArray<FString> ParsedString;
	ClipboardContent.ParseIntoArray(ParsedString, TEXT(";"), true);

	if (ParsedString.Num() != 3)
	{
		return false;
	}

	FSoftObjectPath PhysicsAssetPath(ParsedString[0]);
	OutAsset = Cast<UPhysicsAsset>(PhysicsAssetPath.ResolveObject());

	if (!OutAsset)
	{
		return false;
	}

	OutObjectType = ParsedString[1];

	FSoftObjectPath ObjectAssetPath(ParsedString[2]);
	OutObject = ObjectAssetPath.ResolveObject();

	return OutObject != nullptr;
}

struct FMirrorInfo
{
	FName BoneName;
	int32 BoneIndex;
	int32 BodyIndex;
	int32 ConstraintIndex;
	FMirrorInfo()
	{
		BoneIndex = INDEX_NONE;
		BodyIndex = INDEX_NONE;
		ConstraintIndex = INDEX_NONE;
		BoneName = NAME_None;
	}
};

void FPhysicsAssetEditorSharedData::Mirror()
{
	USkeletalMesh* EditorSkelMesh = PhysicsAsset->GetPreviewMesh();
	if(EditorSkelMesh)
	{

		TArray<FMirrorInfo> MirrorInfos;

		for (const FSelection& Selection : SelectedBodies)
		{
			MirrorInfos.AddUninitialized();
			FMirrorInfo & MirrorInfo = MirrorInfos[MirrorInfos.Num() - 1];
			MirrorInfo.BoneName = PhysicsAsset->SkeletalBodySetups[Selection.Index]->BoneName;
			MirrorInfo.BodyIndex = Selection.Index;
			MirrorInfo.ConstraintIndex = PhysicsAsset->FindConstraintIndex(MirrorInfo.BoneName);
		}

		for (const FSelection& Selection : SelectedConstraints)
		{
			MirrorInfos.AddUninitialized();
			FMirrorInfo & MirrorInfo = MirrorInfos[MirrorInfos.Num() - 1];
			MirrorInfo.BoneName = PhysicsAsset->ConstraintSetup[Selection.Index]->DefaultInstance.ConstraintBone1;
			MirrorInfo.BodyIndex = PhysicsAsset->FindBodyIndex(MirrorInfo.BoneName);
			MirrorInfo.ConstraintIndex = Selection.Index;
		}

		for (FMirrorInfo & MirrorInfo : MirrorInfos)	//mirror all selected bodies/constraints
		{
			int32 BoneIndex = EditorSkelMesh->GetRefSkeleton().FindBoneIndex(MirrorInfo.BoneName);

			int32 MirrorBoneIndex = PhysicsAsset->FindMirroredBone(EditorSkelMesh, BoneIndex);
			if (MirrorBoneIndex != INDEX_NONE)
			{
				UBodySetup * SrcBody = PhysicsAsset->SkeletalBodySetups[MirrorInfo.BodyIndex];
				const FScopedTransaction Transaction(NSLOCTEXT("PhysicsAssetEditor", "MirrorBody", "MirrorBody"));
				MakeNewBody(MirrorBoneIndex, false);

				int32 MirrorBodyIndex = PhysicsAsset->FindControllingBodyIndex(EditorSkelMesh, MirrorBoneIndex);

				UBodySetup * DestBody = PhysicsAsset->SkeletalBodySetups[MirrorBodyIndex];
				DestBody->Modify();
				DestBody->CopyBodyPropertiesFrom(SrcBody);
				
				FQuat ArtistMirrorConvention(1,0,0,0);   //used to be (0 0 1 0)
														 // how Epic Maya artists rig the right and left orientation differently.  todo: perhaps move to cvar W

				for (FKSphylElem& Sphyl : DestBody->AggGeom.SphylElems)
				{
					Sphyl.Rotation	= (Sphyl.Rotation.Quaternion()*ArtistMirrorConvention).Rotator();
					Sphyl.Center = -Sphyl.Center;
				}
				for (FKBoxElem& Box : DestBody->AggGeom.BoxElems)
				{
					Box.Rotation	= (Box.Rotation.Quaternion()*ArtistMirrorConvention).Rotator();
					Box.Center      = -Box.Center;
				}
				for (FKSphereElem& Sphere : DestBody->AggGeom.SphereElems)
				{
					Sphere.Center = -Sphere.Center;
				}
				for (FKTaperedCapsuleElem& TaperedCapsule : DestBody->AggGeom.TaperedCapsuleElems)
				{
					TaperedCapsule.Rotation	= (TaperedCapsule.Rotation.Quaternion()*ArtistMirrorConvention).Rotator();
					TaperedCapsule.Center	= -TaperedCapsule.Center;
				}
				int32 MirrorConstraintIndex = PhysicsAsset->FindConstraintIndex(DestBody->BoneName);
				if(PhysicsAsset->ConstraintSetup.IsValidIndex(MirrorConstraintIndex) && PhysicsAsset->ConstraintSetup.IsValidIndex(MirrorInfo.ConstraintIndex))
				{
					UPhysicsConstraintTemplate * FromConstraint = PhysicsAsset->ConstraintSetup[MirrorInfo.ConstraintIndex];
					UPhysicsConstraintTemplate * ToConstraint = PhysicsAsset->ConstraintSetup[MirrorConstraintIndex];
					CopyConstraintProperties(FromConstraint, ToConstraint);
				}
			}
		}
	}
}

EPhysicsAssetEditorMeshViewMode FPhysicsAssetEditorSharedData::GetCurrentMeshViewMode(bool bSimulation)
{
	if (bSimulation)
	{
		return EditorOptions->SimulationMeshViewMode;
	}
	else
	{
		return EditorOptions->MeshViewMode;
	}
}

EPhysicsAssetEditorCollisionViewMode FPhysicsAssetEditorSharedData::GetCurrentCollisionViewMode(bool bSimulation)
{
	if (bSimulation)
	{
		return EditorOptions->SimulationCollisionViewMode;
	}
	else
	{
		return EditorOptions->CollisionViewMode;
	}
}

EPhysicsAssetEditorConstraintViewMode FPhysicsAssetEditorSharedData::GetCurrentConstraintViewMode(bool bSimulation)
{
	if (bSimulation)
	{
		return EditorOptions->SimulationConstraintViewMode;
	}
	else
	{
		return EditorOptions->ConstraintViewMode;
	}
}

void FPhysicsAssetEditorSharedData::HitBone(int32 BodyIndex, EAggCollisionShape::Type PrimType, int32 PrimIndex, bool bGroupSelect)
{
	if (!bRunningSimulation)
	{
		FPhysicsAssetEditorSharedData::FSelection Selection(BodyIndex, PrimType, PrimIndex);
		if(bGroupSelect)
		{
			if(IsBodySelected(Selection))
			{
				SetSelectedBody(Selection, false);
			}
			else
			{
				SetSelectedBody(Selection, true);
			}
		}
		else
		{
			ClearSelectedBody();
			SetSelectedBody(Selection, true);
		}
	}
}

void FPhysicsAssetEditorSharedData::HitConstraint(int32 ConstraintIndex, bool bGroupSelect)
{
	if (!bRunningSimulation)
	{
		if(bGroupSelect)
		{
			if(IsConstraintSelected(ConstraintIndex))
			{
				SetSelectedConstraint(ConstraintIndex, false);
			}
			else
			{
				SetSelectedConstraint(ConstraintIndex, true);
			}
		}
		else
		{
			ClearSelectedConstraints();
			SetSelectedConstraint(ConstraintIndex, true);
		}
	}
}

void FPhysicsAssetEditorSharedData::RefreshPhysicsAssetChange(const UPhysicsAsset* InPhysAsset, bool bFullClothRefresh)
{
	if (InPhysAsset)
	{
		InPhysAsset->RefreshPhysicsAssetChange();

		// Broadbcast delegate
		FPhysicsDelegates::OnPhysicsAssetChanged.Broadcast(InPhysAsset);

		FEditorSupportDelegates::RedrawAllViewports.Broadcast();
		// since we recreate physicsstate, a lot of transient state data will be gone
		// so have to turn simulation off again. 
		// ideally maybe in the future, we'll fix it by controlling tick?
		EditorSkelComp->RecreatePhysicsState();
		if(bFullClothRefresh)
		{
			EditorSkelComp->RecreateClothingActors();
		}
		else
		{
			UpdateClothPhysics();
		}
		EnableSimulation(false);
	}
}

void FPhysicsAssetEditorSharedData::SetSelectedBodyAnyPrim(int32 BodyIndex, bool bSelected)
{
	SetSelectedBodiesAnyPrim({ BodyIndex }, bSelected);
}

void FPhysicsAssetEditorSharedData::SetSelectedBodiesAnyPrim(const TArray<int32>& BodiesIndices, bool bSelected)
{
	if (BodiesIndices.Num() == 0)
	{
		return;
	}

	if (BodiesIndices.Num() == 1 && BodiesIndices[0] == INDEX_NONE)
	{
		ClearSelectedBody();
		return;
	}

	TArray<FSelection> NewSelection;
	for (const int32 BodyIndex : BodiesIndices)
	{
		UBodySetup* BodySetup = PhysicsAsset->SkeletalBodySetups[BodyIndex];
		check(BodySetup);

		if (BodySetup->AggGeom.SphereElems.Num() > 0)
		{
			NewSelection.Add(FSelection(BodyIndex, EAggCollisionShape::Sphere, 0));
		}
		else if (BodySetup->AggGeom.BoxElems.Num() > 0)
		{
			NewSelection.Add(FSelection(BodyIndex, EAggCollisionShape::Box, 0));
		}
		else if (BodySetup->AggGeom.SphylElems.Num() > 0)
		{
			NewSelection.Add(FSelection(BodyIndex, EAggCollisionShape::Sphyl, 0));
		}
		else if (BodySetup->AggGeom.ConvexElems.Num() > 0)
		{
			NewSelection.Add(FSelection(BodyIndex, EAggCollisionShape::Convex, 0));
		}
		else if (BodySetup->AggGeom.TaperedCapsuleElems.Num() > 0)
		{
			NewSelection.Add(FSelection(BodyIndex, EAggCollisionShape::TaperedCapsule, 0));
		}
		else
		{
			UE_LOG(LogPhysicsAssetEditor, Fatal, TEXT("Body Setup with index %d has No Primitives!"), BodyIndex);
		}
	}

	if (NewSelection.Num() > 0)
	{
		SetSelectedBodies(NewSelection, bSelected);
	}
}

void FPhysicsAssetEditorSharedData::SetSelectedBodiesAllPrim(const TArray<int32>& BodiesIndices, bool bSelected)
{
	if (BodiesIndices.Num() == 0)
	{
		return;
	}

	if (BodiesIndices.Num() == 1 && BodiesIndices[0] == INDEX_NONE)
	{
		ClearSelectedBody();
		return;
	}

	TArray<FSelection> NewSelection;
	for (const int32 BodyIndex : BodiesIndices)
	{
		UBodySetup* BodySetup = PhysicsAsset->SkeletalBodySetups[BodyIndex];
		check(BodySetup);

		for (int32 PrimitiveIndex = 0; PrimitiveIndex < BodySetup->AggGeom.SphereElems.Num(); ++PrimitiveIndex)
		{
			NewSelection.Add(FSelection(BodyIndex, EAggCollisionShape::Sphere, PrimitiveIndex));
		}

		for (int32 PrimitiveIndex = 0; PrimitiveIndex < BodySetup->AggGeom.BoxElems.Num(); ++PrimitiveIndex)
		{
			NewSelection.Add(FSelection(BodyIndex, EAggCollisionShape::Box, PrimitiveIndex));
		}

		for (int32 PrimitiveIndex = 0; PrimitiveIndex < BodySetup->AggGeom.SphylElems.Num(); ++PrimitiveIndex)
		{
			NewSelection.Add(FSelection(BodyIndex, EAggCollisionShape::Sphyl, PrimitiveIndex));
		}

		for (int32 PrimitiveIndex = 0; PrimitiveIndex < BodySetup->AggGeom.ConvexElems.Num(); ++PrimitiveIndex)
		{
			NewSelection.Add(FSelection(BodyIndex, EAggCollisionShape::Convex, PrimitiveIndex));
		}
		for (int32 PrimitiveIndex = 0; PrimitiveIndex < BodySetup->AggGeom.TaperedCapsuleElems.Num(); ++PrimitiveIndex)
		{
			NewSelection.Add(FSelection(BodyIndex, EAggCollisionShape::TaperedCapsule, PrimitiveIndex));
		}
	}

	if (NewSelection.Num() > 0)
	{
		SetSelectedBodies(NewSelection, bSelected);
	}
}

void FPhysicsAssetEditorSharedData::ClearSelectedBody()
{
	SelectedBodies.Empty();
	SelectedConstraints.Empty();
	BroadcastSelectionChanged();
}

void FPhysicsAssetEditorSharedData::SetSelectedBody(const FSelection& Body, bool bSelected)
{
	SetSelectedBodies({ Body }, bSelected);
}

void FPhysicsAssetEditorSharedData::SetSelectedBodies(const TArray<FSelection>& Bodies, bool bSelected)
{
	if (InsideSelChange || Bodies.Num() == 0)
	{
		return;
	}

	if (bSelected)
	{
		for (const FSelection& Body : Bodies)
		{
			SelectedBodies.AddUnique(Body);
		}
	}
	else
	{
		for (const FSelection& Body : Bodies)
		{
			SelectedBodies.Remove(Body);
		}
	}

	BroadcastSelectionChanged();

	if (!GetSelectedBody())
	{
		return;
	}

	UpdateNoCollisionBodies();
	++InsideSelChange;
	BroadcastPreviewChanged();
	--InsideSelChange;
}

bool FPhysicsAssetEditorSharedData::IsBodySelected(const FSelection& Body) const
{
	return SelectedBodies.Contains(Body);
}

void FPhysicsAssetEditorSharedData::ToggleSelectionType(bool bIgnoreUserConstraints)
{
	TSet<int32> NewSelectedBodies; 
	for (const FSelection& Selection : SelectedConstraints)
	{
		UPhysicsConstraintTemplate* ConstraintTemplate = PhysicsAsset->ConstraintSetup[Selection.Index];
		FConstraintInstance & DefaultInstance = ConstraintTemplate->DefaultInstance;

		for (int32 BodyIdx = 0; BodyIdx < PhysicsAsset->SkeletalBodySetups.Num(); ++BodyIdx)
		{
			UBodySetup* BodySetup = PhysicsAsset->SkeletalBodySetups[BodyIdx];

			// no need to account for bIgnoreUserConstraints when selecting from constraints to bodies
			if (ConstraintTemplate->DefaultInstance.ConstraintBone1 == BodySetup->BoneName)
			{
				if (BodySetup->AggGeom.GetElementCount() > 0 && !NewSelectedBodies.Contains(BodyIdx))
				{
					NewSelectedBodies.Add(BodyIdx);
				}
			}
		}
	}

	TSet<int32> NewSelectedConstraints; //We could have multiple shapes selected which would cause us to add and remove the same constraint.
	for (const FSelection& Selection : SelectedBodies)
	{
		UBodySetup* BodySetup = PhysicsAsset->SkeletalBodySetups[Selection.Index];
		for(int32 ConstraintIdx = 0; ConstraintIdx < PhysicsAsset->ConstraintSetup.Num(); ++ConstraintIdx)
		{
			const UPhysicsConstraintTemplate* ConstraintTemplate = PhysicsAsset->ConstraintSetup[ConstraintIdx];

			bool bConstraintIsConnectedToBone = (ConstraintTemplate->DefaultInstance.JointName == BodySetup->BoneName);
			if (!bIgnoreUserConstraints)
			{
				bConstraintIsConnectedToBone |= (ConstraintTemplate->DefaultInstance.ConstraintBone1 == BodySetup->BoneName);
			}
			if (bConstraintIsConnectedToBone)
			{
				if (!NewSelectedConstraints.Contains(ConstraintIdx))
				{
					NewSelectedConstraints.Add(ConstraintIdx);
				}
			}
		}
	}
	
	ClearSelectedBody();
	ClearSelectedConstraints();

	SetSelectedBodiesAllPrim(NewSelectedBodies.Array(), true);
	SetSelectedConstraints(NewSelectedConstraints.Array(), true);
}

void FPhysicsAssetEditorSharedData::ToggleShowSelected()
{
	bool bAllSelectedVisible = true;
	if (bAllSelectedVisible)
	{
		for (const FSelection& Selection : SelectedConstraints)
		{
			if (IsConstraintHidden(Selection.Index))
			{
				bAllSelectedVisible = false;
				break;
			}
		}
	}
	if (bAllSelectedVisible)
	{
		for (const FSelection& Selection : SelectedBodies)
		{
			if (IsBodyHidden(Selection.Index))
			{
				bAllSelectedVisible = false;
			}
		}
	}

	if (bAllSelectedVisible)
	{
		HideSelected();
	}
	else
	{
		ShowSelected();
	}
}

void FPhysicsAssetEditorSharedData::ToggleShowOnlySelected()
{
	// Show only selected: make selected items visible and all others invisible.
	// If we are already in the ShowOnlySelected state, make all visible.
	bool bAllSelectedVisible = true;
	if (bAllSelectedVisible)
	{
		for (const FSelection& Selection : SelectedConstraints)
		{
			if (IsConstraintHidden(Selection.Index))
			{
				bAllSelectedVisible = false;
				break;
			}
		}
	}
	if (bAllSelectedVisible)
	{
		for (const FSelection& Selection : SelectedBodies)
		{
			if (IsBodyHidden(Selection.Index))
			{
				bAllSelectedVisible = false;
			}
		}
	}

	bool bAllNotSelectedHidden = true;
	if (bAllNotSelectedHidden)
	{
		for (int32 ConstraintIndex = 0; ConstraintIndex < PhysicsAsset->ConstraintSetup.Num(); ++ConstraintIndex)
		{
			// Look at unselected constraints
			if (!SelectedConstraints.ContainsByPredicate([ConstraintIndex](FSelection& V) { return V.Index == ConstraintIndex; } ))
			{
				// Is it hidden?
				if (!IsConstraintHidden(ConstraintIndex))
				{
					bAllNotSelectedHidden = false;
					break;
				}
			}
		}
	}
	if (bAllNotSelectedHidden)
	{
		for (int32 BodyIndex = 0; BodyIndex < PhysicsAsset->SkeletalBodySetups.Num(); ++BodyIndex)
		{
			// Look at unselected bodies
			if (!SelectedBodies.ContainsByPredicate([BodyIndex](FSelection& V) { return V.Index == BodyIndex; }))
			{
				// Is it hidden?
				if (!IsBodyHidden(BodyIndex))
				{
					bAllNotSelectedHidden = false;
					break;
				}
			}
		}
	}

	if (bAllSelectedVisible && bAllNotSelectedHidden)
	{
		ShowAll();
	}
	else
	{
		HideAll();
		ShowSelected();
	}
}

bool FPhysicsAssetEditorSharedData::IsBodyHidden(const int32 BodyIndex) const
{
	if (FPhysicsAssetRenderSettings* const PhysicsAssetRenderSettings = GetRenderSettings())
	{
		return PhysicsAssetRenderSettings->IsBodyHidden(BodyIndex);
	}
	
	return false;
}

bool FPhysicsAssetEditorSharedData::IsConstraintHidden(const int32 ConstraintIndex) const
{
	if (FPhysicsAssetRenderSettings* const PhysicsAssetRenderSettings = GetRenderSettings())
	{
		return PhysicsAssetRenderSettings->IsConstraintHidden(ConstraintIndex);
	}

	return false;
}

void FPhysicsAssetEditorSharedData::HideBody(const int32 BodyIndex)
{
	if (FPhysicsAssetRenderSettings* const PhysicsAssetRenderSettings = GetRenderSettings())
	{
		PhysicsAssetRenderSettings->HideBody(BodyIndex);
	}
}

void FPhysicsAssetEditorSharedData::ShowBody(const int32 BodyIndex)
{
	if (FPhysicsAssetRenderSettings* const PhysicsAssetRenderSettings = GetRenderSettings())
	{
		PhysicsAssetRenderSettings->ShowBody(BodyIndex);
	}
}

void FPhysicsAssetEditorSharedData::HideConstraint(const int32 ConstraintIndex)
{
	if (FPhysicsAssetRenderSettings* const PhysicsAssetRenderSettings = GetRenderSettings())
	{
		PhysicsAssetRenderSettings->HideConstraint(ConstraintIndex);
	}
}

void FPhysicsAssetEditorSharedData::ShowConstraint(const int32 ConstraintIndex)
{
	if (FPhysicsAssetRenderSettings* const PhysicsAssetRenderSettings = GetRenderSettings())
	{
		PhysicsAssetRenderSettings->ShowConstraint(ConstraintIndex);
	}
}

void FPhysicsAssetEditorSharedData::ShowAll()
{
	if (FPhysicsAssetRenderSettings* const PhysicsAssetRenderSettings = GetRenderSettings())
	{
		PhysicsAssetRenderSettings->ShowAll();
	}
}

void FPhysicsAssetEditorSharedData::HideAllBodies()
{
	if (FPhysicsAssetRenderSettings* const PhysicsAssetRenderSettings = GetRenderSettings())
	{
		PhysicsAssetRenderSettings->HideAllBodies(PhysicsAsset);
	}
}

void FPhysicsAssetEditorSharedData::HideAllConstraints()
{
	if (FPhysicsAssetRenderSettings* const PhysicsAssetRenderSettings = GetRenderSettings())
	{
		PhysicsAssetRenderSettings->HideAllConstraints(PhysicsAsset);
	}
}

void FPhysicsAssetEditorSharedData::HideAll()
{
	HideAllBodies();
	HideAllConstraints();
}

void FPhysicsAssetEditorSharedData::ShowSelected()
{
	for (const FSelection& Selection : SelectedConstraints)
	{
		ShowConstraint(Selection.Index);
	}
	for (const FSelection& Selection : SelectedBodies)
	{
		ShowBody(Selection.Index);
	}
}

void FPhysicsAssetEditorSharedData::HideSelected()
{
	for (const FSelection& Selection : SelectedConstraints)
	{
		HideConstraint(Selection.Index);
	}
	for (const FSelection& Selection : SelectedBodies)
	{
		HideBody(Selection.Index);
	}
}

void FPhysicsAssetEditorSharedData::ToggleShowOnlyColliding()
{
	// important that we check this before calling ShowAll
	bool bIsShowingColliding = true;

	for (const int32 BodyIndex : NoCollisionBodies)
	{
		bIsShowingColliding &= IsBodyHidden(BodyIndex);

		if (!bIsShowingColliding)
		{
			break;
		}
	}

	// in any case first show all
	ShowAll();

	FPhysicsAssetRenderSettings* const PhysicsAssetRenderSettings = GetRenderSettings();
	
	// only works if one only body is selected
	if (!bIsShowingColliding && PhysicsAssetRenderSettings && (SelectedBodies.Num() == 1))
	{	
		// NoCollisionBodies already contains the non colliding bodies from the one selection
		PhysicsAssetRenderSettings->SetHiddenBodies(NoCollisionBodies);
	}

}

void FPhysicsAssetEditorSharedData::ToggleShowOnlyConstrained()
{
	if (PhysicsAsset == nullptr)
	{
		return;
	}

	// important that we check this before calling ShowAll
	{
		FPhysicsAssetRenderSettings* const PhysicsAssetRenderSettings = GetRenderSettings();
		if (PhysicsAssetRenderSettings && PhysicsAssetRenderSettings->AreAnyBodiesHidden())
		{
			PhysicsAssetRenderSettings->ShowAllBodies();
			return;
		}
	}

	// first Hide all bodies and then show only the ones that needs to be
	HideAllBodies();

	// add  the current selection of bodies
	for (const FSelection& SelectedBody : SelectedBodies)
	{
		ShowBody(SelectedBody.Index);
	}

	// collect connected bodies from the selected constraints
	for (const FSelection& Selection : SelectedConstraints)
	{
		UPhysicsConstraintTemplate* ConstraintTemplate = PhysicsAsset->ConstraintSetup[Selection.Index];
		FConstraintInstance& DefaultInstance = ConstraintTemplate->DefaultInstance;

		// Add both connected bodies
		int32 Body1IndexToAdd = PhysicsAsset->FindBodyIndex(DefaultInstance.ConstraintBone1);
		if (Body1IndexToAdd != INDEX_NONE)
		{
			ShowBody(Body1IndexToAdd);
		}
		int32 Body2IndexToAdd = PhysicsAsset->FindBodyIndex(DefaultInstance.ConstraintBone2);
		if (Body2IndexToAdd != INDEX_NONE)
		{
			ShowBody(Body2IndexToAdd);
		}
	}

	// collect connected bodies from the selected bodies
	for (const FSelection& Selection : SelectedBodies)
	{
		UBodySetup* BodySetup = PhysicsAsset->SkeletalBodySetups[Selection.Index];
		for (int32 ConstraintIdx = 0; ConstraintIdx < PhysicsAsset->ConstraintSetup.Num(); ++ConstraintIdx)
		{
			const UPhysicsConstraintTemplate* ConstraintTemplate = PhysicsAsset->ConstraintSetup[ConstraintIdx];
			FName OtherConnectedBody;
			if (ConstraintTemplate->DefaultInstance.ConstraintBone1 == BodySetup->BoneName)
			{
				OtherConnectedBody = ConstraintTemplate->DefaultInstance.ConstraintBone2;
			}
			else if (ConstraintTemplate->DefaultInstance.ConstraintBone2 == BodySetup->BoneName)
			{
				OtherConnectedBody = ConstraintTemplate->DefaultInstance.ConstraintBone1;
			}
			if (!OtherConnectedBody.IsNone())
			{
				int32 BodyIndexToAdd = PhysicsAsset->FindBodyIndex(OtherConnectedBody);
				if (BodyIndexToAdd != INDEX_NONE)
				{
					ShowBody(BodyIndexToAdd);
				}
			}
		}
	}
}

void FPhysicsAssetEditorSharedData::UpdateNoCollisionBodies()
{
	NoCollisionBodies.Empty();

	// Query disable table with selected body and every other body.
	for (int32 i = 0; i <PhysicsAsset->SkeletalBodySetups.Num(); ++i)
	{
		if (!ensure(PhysicsAsset->SkeletalBodySetups[i]))
		{
			continue;
		}
		// Add any bodies with bNoCollision
		if (PhysicsAsset->SkeletalBodySetups[i]->DefaultInstance.GetCollisionEnabled() == ECollisionEnabled::NoCollision)
		{
			NoCollisionBodies.Add(i);
		}
		else if (GetSelectedBody() && i != GetSelectedBody()->Index)
		{
			if (!ensure(PhysicsAsset->SkeletalBodySetups[GetSelectedBody()->Index]))
			{
				continue;
			}
			// Add this body if it has disabled collision with selected.
			FRigidBodyIndexPair Key(i, GetSelectedBody()->Index);

			if (PhysicsAsset->SkeletalBodySetups[GetSelectedBody()->Index]->DefaultInstance.GetCollisionEnabled() == ECollisionEnabled::NoCollision ||
				PhysicsAsset->CollisionDisableTable.Find(Key))
			{
				NoCollisionBodies.Add(i);
			}
		}
	}
}

void FPhysicsAssetEditorSharedData::ClearSelectedConstraints()
{
	if(InsideSelChange)
	{
		return;
	}

	SelectedBodies.Empty();
	SelectedConstraints.Empty();

	BroadcastSelectionChanged();

	++InsideSelChange;
	BroadcastPreviewChanged();
	--InsideSelChange;
}

void FPhysicsAssetEditorSharedData::SetSelectedConstraint(int32 ConstraintIndex, bool bSelected)
{
	SetSelectedConstraints({ ConstraintIndex }, bSelected);
}

void FPhysicsAssetEditorSharedData::SetSelectedConstraints(const TArray<int32> ConstraintsIndices, bool bSelected)
{
	if (ConstraintsIndices.Num() == 0)
	{
		return;
	}

	if (InsideSelChange)
	{
		return;
	}

	bool bSelectionchanged = false;
	for (int32 ConstraintIndex : ConstraintsIndices)
	{
		if (ConstraintIndex != INDEX_NONE)
		{
			FSelection Constraint(ConstraintIndex, EAggCollisionShape::Unknown, INDEX_NONE);
			if (bSelected)
			{
				SelectedConstraints.AddUnique(Constraint);
			}
			else
			{
				SelectedConstraints.Remove(Constraint);
			}
			bSelectionchanged = true;
		}
	}

	if (bSelectionchanged)
	{
		BroadcastSelectionChanged();

		++InsideSelChange;
		BroadcastPreviewChanged();
		--InsideSelChange;
	}
}

bool FPhysicsAssetEditorSharedData::IsConstraintSelected(int32 ConstraintIndex) const
{
	FSelection Constraint(ConstraintIndex, EAggCollisionShape::Unknown, INDEX_NONE);
	return SelectedConstraints.Contains(Constraint);
}

void FPhysicsAssetEditorSharedData::SetCollisionBetweenSelected(bool bEnableCollision)
{
	if (bRunningSimulation || SelectedBodies.Num() == 0)
	{
		return;
	}

	PhysicsAsset->Modify();

	for(int32 i=0; i<SelectedBodies.Num(); ++i)
	{
		for(int32 j=i+1; j<SelectedBodies.Num(); ++j)
		{
			if(bEnableCollision)
			{
				PhysicsAsset->EnableCollision(SelectedBodies[i].Index, SelectedBodies[j].Index);
			}else
			{
				PhysicsAsset->DisableCollision(SelectedBodies[i].Index, SelectedBodies[j].Index);
			}

		}
	}


	UpdateNoCollisionBodies();

	BroadcastPreviewChanged();
}

bool FPhysicsAssetEditorSharedData::CanSetCollisionBetweenSelected(bool bEnableCollision) const
{
	if (bRunningSimulation || SelectedBodies.Num() == 0)
	{
		return false;
	}

	for(int32 i=0; i<SelectedBodies.Num(); ++i)
	{
		for(int32 j=i+1; j<SelectedBodies.Num(); ++j)
		{
			if(PhysicsAsset->IsCollisionEnabled(SelectedBodies[i].Index, SelectedBodies[j].Index) != bEnableCollision)
			{
				return true;
			}
		}
	}

	return false;
}

void FPhysicsAssetEditorSharedData::SetCollisionBetweenSelectedAndAll(bool bEnableCollision)
{
	if (bRunningSimulation || SelectedBodies.Num() == 0)
	{
		return;
	}

	PhysicsAsset->Modify();

	for(int32 i=0; i<SelectedBodies.Num(); ++i)
	{
		for(int32 j = 0; j < PhysicsAsset->SkeletalBodySetups.Num(); ++j)
		{
			if(bEnableCollision)
			{
				PhysicsAsset->EnableCollision(SelectedBodies[i].Index, j);
			}
			else
			{
				PhysicsAsset->DisableCollision(SelectedBodies[i].Index, j);
			}

		}
	}

	UpdateNoCollisionBodies();

	BroadcastPreviewChanged();
}

bool FPhysicsAssetEditorSharedData::CanSetCollisionBetweenSelectedAndAll(bool bEnableCollision) const
{
	if (bRunningSimulation || SelectedBodies.Num() == 0)
	{
		return false;
	}

	for(int32 i=0; i<SelectedBodies.Num(); ++i)
	{
		for(int32 j = 0; j < PhysicsAsset->SkeletalBodySetups.Num(); ++j)
		{
			if(PhysicsAsset->IsCollisionEnabled(SelectedBodies[i].Index, j) != bEnableCollision)
			{
				return true;
			}
		}
	}

	return false;
}

void FPhysicsAssetEditorSharedData::SetCollisionBetween(int32 Body1Index, int32 Body2Index, bool bEnableCollision)
{
	if (bRunningSimulation)
	{
		return;
	}

	PhysicsAsset->Modify();

	if (Body1Index != INDEX_NONE && Body2Index != INDEX_NONE && Body1Index != Body2Index)
	{
		if (bEnableCollision)
		{
			PhysicsAsset->EnableCollision(Body1Index, Body2Index);
		}
		else
		{
			PhysicsAsset->DisableCollision(Body1Index, Body2Index);
		}

		UpdateNoCollisionBodies();
	}

	BroadcastPreviewChanged();
}

void FPhysicsAssetEditorSharedData::SetPrimitiveCollision(ECollisionEnabled::Type CollisionEnabled)
{
	if (bRunningSimulation)
	{
		return;
	}

	PhysicsAsset->Modify();

	for (FSelection SelectedBody : SelectedBodies)
	{
		PhysicsAsset->SetPrimitiveCollision(SelectedBody.Index, SelectedBody.PrimitiveType, SelectedBody.PrimitiveIndex, CollisionEnabled);
	}

	BroadcastPreviewChanged();
}

bool FPhysicsAssetEditorSharedData::CanSetPrimitiveCollision(ECollisionEnabled::Type CollisionEnabled) const
{
	if (bRunningSimulation || SelectedBodies.Num() == 0)
	{
		return false;
	}

	return true;
}

bool FPhysicsAssetEditorSharedData::GetIsPrimitiveCollisionEnabled(ECollisionEnabled::Type CollisionEnabled) const
{
	for (const FSelection& SelectedBody : SelectedBodies)
	{
		if (PhysicsAsset->GetPrimitiveCollision(SelectedBody.Index, SelectedBody.PrimitiveType, SelectedBody.PrimitiveIndex) == CollisionEnabled)
		{
			return true;
		}
	}

	return false;
}

void FPhysicsAssetEditorSharedData::SetPrimitiveContributeToMass(bool bContributeToMass)
{
	for (const FSelection& SelectedBody : SelectedBodies)
	{
		PhysicsAsset->SetPrimitiveContributeToMass(SelectedBody.Index, SelectedBody.PrimitiveType, SelectedBody.PrimitiveIndex, bContributeToMass);
	}
}

bool FPhysicsAssetEditorSharedData::CanSetPrimitiveContributeToMass() const
{
	return true;
}

bool FPhysicsAssetEditorSharedData::GetPrimitiveContributeToMass() const
{
	for (const FSelection& SelectedBody : SelectedBodies)
	{
		if (PhysicsAsset->GetPrimitiveContributeToMass(SelectedBody.Index, SelectedBody.PrimitiveType, SelectedBody.PrimitiveIndex))
		{
			return true;
		}
	}

	return false;
}

static EAggCollisionShape::Type ConvertPhysicsAssetGeomTypeToAggCollisionShapeType(EPhysAssetFitGeomType PhysicsAssetGeomType)
{
	switch (PhysicsAssetGeomType)
	{
	case EPhysAssetFitGeomType::EFG_Box:				return EAggCollisionShape::Type::Box;
	case EPhysAssetFitGeomType::EFG_Sphyl:				return EAggCollisionShape::Type::Sphyl;
	case EPhysAssetFitGeomType::EFG_Sphere:				return EAggCollisionShape::Type::Sphere;
	case EPhysAssetFitGeomType::EFG_TaperedCapsule: 	return EAggCollisionShape::Type::TaperedCapsule;
	case EPhysAssetFitGeomType::EFG_SingleConvexHull:	return EAggCollisionShape::Type::Convex;
	case EPhysAssetFitGeomType::EFG_MultiConvexHull:	return EAggCollisionShape::Type::Convex;
	default:											return EAggCollisionShape::Type::Unknown;
	}
}

void FPhysicsAssetEditorSharedData::AutoNameAllPrimitives(int32 BodyIndex, EPhysAssetFitGeomType PrimitiveType)
{
	AutoNameAllPrimitives(BodyIndex, ConvertPhysicsAssetGeomTypeToAggCollisionShapeType(PrimitiveType));
}

void FPhysicsAssetEditorSharedData::AutoNameAllPrimitives(int32 BodyIndex, EAggCollisionShape::Type PrimitiveType)
{
	if (!PhysicsAsset || !PhysicsAsset->SkeletalBodySetups.IsValidIndex(BodyIndex))
	{
		return;
	}

	if (UBodySetup* BodySetup = PhysicsAsset->SkeletalBodySetups[BodyIndex])
	{
		int32 PrimitiveCount = 0;
		switch (PrimitiveType)
		{
		case EAggCollisionShape::Sphere:
			PrimitiveCount = BodySetup->AggGeom.SphereElems.Num();
			break;
		case EAggCollisionShape::Box:
			PrimitiveCount = BodySetup->AggGeom.BoxElems.Num();
			break;
		case EAggCollisionShape::Sphyl:
			PrimitiveCount = BodySetup->AggGeom.SphylElems.Num();
			break;
		case EAggCollisionShape::Convex:
			PrimitiveCount = BodySetup->AggGeom.ConvexElems.Num();
			break;
		case EAggCollisionShape::TaperedCapsule:
			PrimitiveCount = BodySetup->AggGeom.TaperedCapsuleElems.Num();
			break;
		}

		for (int32 PrimitiveIndex = 0; PrimitiveIndex < PrimitiveCount; PrimitiveIndex++)
		{
			AutoNamePrimitive(BodyIndex, PrimitiveType, PrimitiveIndex);
		}
	}
}

void FPhysicsAssetEditorSharedData::AutoNamePrimitive(int32 BodyIndex, EAggCollisionShape::Type PrimitiveType, int32 PrimitiveIndex)
{
	if (!PhysicsAsset || !PhysicsAsset->SkeletalBodySetups.IsValidIndex(BodyIndex))
	{
		return;
	}

	if (UBodySetup* BodySetup = PhysicsAsset->SkeletalBodySetups[BodyIndex])
	{
		if (PrimitiveType == EAggCollisionShape::Sphere)
		{
			if (PrimitiveIndex == INDEX_NONE)
			{
				PrimitiveIndex = BodySetup->AggGeom.SphereElems.Num() - 1;
			}
			if (BodySetup->AggGeom.SphereElems.IsValidIndex(PrimitiveIndex))
			{
				FName PrimitiveName(FString::Printf(TEXT("%s_sphere"), *BodySetup->BoneName.ToString()));
				BodySetup->AggGeom.SphereElems[PrimitiveIndex].SetName(PrimitiveName);
			}
		}
		else if (PrimitiveType == EAggCollisionShape::Box)
		{
			if (PrimitiveIndex == INDEX_NONE)
			{
				PrimitiveIndex = BodySetup->AggGeom.BoxElems.Num() - 1;
			}
			if (BodySetup->AggGeom.BoxElems.IsValidIndex(PrimitiveIndex))
			{
				FName PrimitiveName(FString::Printf(TEXT("%s_box"), *BodySetup->BoneName.ToString()));
				BodySetup->AggGeom.BoxElems[PrimitiveIndex].SetName(PrimitiveName);
			}
		}
		else if (PrimitiveType == EAggCollisionShape::Sphyl)
		{
			if (PrimitiveIndex == INDEX_NONE)
			{
				PrimitiveIndex = BodySetup->AggGeom.SphylElems.Num() - 1;
			}
			if (BodySetup->AggGeom.SphylElems.IsValidIndex(PrimitiveIndex))
			{
				FName PrimitiveName(FString::Printf(TEXT("%s_capsule"), *BodySetup->BoneName.ToString()));
				BodySetup->AggGeom.SphylElems[PrimitiveIndex].SetName(PrimitiveName);
			}
		}
		else if (PrimitiveType == EAggCollisionShape::Convex)
		{
			if (PrimitiveIndex == INDEX_NONE)
			{
				PrimitiveIndex = BodySetup->AggGeom.ConvexElems.Num() - 1;
			}
			if (BodySetup->AggGeom.ConvexElems.IsValidIndex(PrimitiveIndex))
			{
				FName PrimitiveName(FString::Printf(TEXT("%s_convex"), *BodySetup->BoneName.ToString()));
				BodySetup->AggGeom.ConvexElems[PrimitiveIndex].SetName(PrimitiveName);
			}
		}
		else if (PrimitiveType == EAggCollisionShape::TaperedCapsule)
		{
			if (PrimitiveIndex == INDEX_NONE)
			{
				PrimitiveIndex = BodySetup->AggGeom.TaperedCapsuleElems.Num() - 1;
			}
			if (BodySetup->AggGeom.TaperedCapsuleElems.IsValidIndex(PrimitiveIndex))
			{
				FName PrimitiveName(FString::Printf(TEXT("%s_tapered_capsule"), *BodySetup->BoneName.ToString()));
				BodySetup->AggGeom.TaperedCapsuleElems[PrimitiveIndex].SetName(PrimitiveName);
			}
		}
	}
}

void FPhysicsAssetEditorSharedData::CopySelectedBodiesAndConstraintsToClipboard(int32& OutNumCopiedBodies, int32& OutNumCopiedConstraints)
{
	OutNumCopiedBodies = 0;
	OutNumCopiedConstraints = 0;
	if (PhysicsAsset)
	{
		// Clear the mark state for saving.
		UnMarkAllObjects(EObjectMark(OBJECTMARK_TagExp | OBJECTMARK_TagImp));

		FStringOutputDevice Archive;
		const FExportObjectInnerContext Context;

		// export bodies first 
		{
			OutNumCopiedBodies = 0;
			TSet<int32> ExportedBodyIndices;

			// Export each of the selected nodes
			for (const FSelection& SelectedBody : SelectedBodies)
			{
				// selected bodies contain the primitives, so abody can be stored multiple time for each of its primitive
				// we need to make sure we process it only once
				if (!ExportedBodyIndices.Contains(SelectedBody.Index))
				{
					ExportedBodyIndices.Add(SelectedBody.Index);

					if (USkeletalBodySetup* BodySetup = PhysicsAsset->SkeletalBodySetups[SelectedBody.Index])
					{						
						UExporter::ExportToOutputDevice(&Context, BodySetup, NULL, Archive, TEXT("copy"), 0, PPF_ExportsNotFullyQualified | PPF_Copy | PPF_Delimited, false);
						++OutNumCopiedBodies;
					}
				}
			}
		}

		// export constraint next 
		{
			OutNumCopiedConstraints = 0;
			TSet<int32> ExportedConstraintIndices;

			// Export each of the selected nodes
			for (const FSelection& SelectedConstraint : SelectedConstraints)
			{
				// selected bodies contain the primitives, so abody can be stored multiple time for each of its primitive
				// we need to make sure we process it only once
				if (!ExportedConstraintIndices.Contains(SelectedConstraint.Index))
				{
					ExportedConstraintIndices.Add(SelectedConstraint.Index);

					if (UPhysicsConstraintTemplate* ConstraintSetup = PhysicsAsset->ConstraintSetup[SelectedConstraint.Index])
					{
						UExporter::ExportToOutputDevice(&Context, ConstraintSetup, NULL, Archive, TEXT("copy"), 0, PPF_ExportsNotFullyQualified | PPF_Copy | PPF_Delimited, false);
						++OutNumCopiedConstraints;
					}
				}
			}
		}

		// save to clipboard as text 
		FString ExportedText = Archive;
		FPlatformApplicationMisc::ClipboardCopy(*ExportedText);
	}
}

class FSkeletalBodyAndConstraintSetupObjectTextFactory : public FCustomizableTextObjectFactory
{
public:
	FSkeletalBodyAndConstraintSetupObjectTextFactory()
		: FCustomizableTextObjectFactory(GWarn)
	{
	}

	// FCustomizableTextObjectFactory implementation
	virtual bool CanCreateClass(UClass* InObjectClass, bool& bOmitSubObjs) const override
	{
		return (InObjectClass->IsChildOf<USkeletalBodySetup>() || InObjectClass->IsChildOf<UPhysicsConstraintTemplate>());
	}

	virtual void ProcessConstructedObject(UObject* NewObject) override
	{
		check(NewObject);
		if (NewObject->IsA<USkeletalBodySetup>())
		{
			NewBodySetups.Add(Cast<USkeletalBodySetup>(NewObject));
		}
		else if (NewObject->IsA<UPhysicsConstraintTemplate>())
		{
			NewConstraintTemplates.Add(Cast<UPhysicsConstraintTemplate>(NewObject));
		}
	}

public:
	TArray<USkeletalBodySetup*> NewBodySetups;
	TArray<UPhysicsConstraintTemplate*> NewConstraintTemplates;
};

void FPhysicsAssetEditorSharedData::PasteBodiesAndConstraintsFromClipboard(int32& OutNumPastedBodies, int32& OutNumPastedConstraints)
{
	OutNumPastedBodies = 0;
	OutNumPastedConstraints = 0;
	if (PhysicsAsset)
	{
		FString TextToImport;
		FPlatformApplicationMisc::ClipboardPaste(TextToImport);

		if (!TextToImport.IsEmpty())
		{
			UPackage* TempPackage = NewObject<UPackage>(nullptr, TEXT("/Engine/Editor/PhysicsAssetEditor/Transient"), RF_Transient);
			TempPackage->AddToRoot();
			{
				// Turn the text buffer into objects
				FSkeletalBodyAndConstraintSetupObjectTextFactory  Factory;
				Factory.ProcessBuffer(TempPackage, RF_Transactional, TextToImport);

				// transaction block 
				if (Factory.NewBodySetups.Num() > 0 || Factory.NewConstraintTemplates.Num() > 0)
				{
					const FScopedTransaction Transaction(NSLOCTEXT("PhysicsAssetEditor", "PasteBodiesAndConstraintsFromClipboard", "Paste Bodies And Constraints From Clipboard"));

					PhysicsAsset->Modify();

					// let's first process the bodies
					OutNumPastedBodies = 0;
					for (USkeletalBodySetup* PastedBodySetup : Factory.NewBodySetups)
					{
						// doe sthis bone exist in the target physics asset?
						int32 BodyIndex = PhysicsAsset->FindBodyIndex(PastedBodySetup->BoneName);
						if (BodyIndex == INDEX_NONE)
						{
							// none found, create a brand new one 
							const FPhysAssetCreateParams& NewBodyData = GetDefault<UPhysicsAssetGenerationSettings>()->CreateParams;
							BodyIndex = FPhysicsAssetUtils::CreateNewBody(PhysicsAsset, PastedBodySetup->BoneName, NewBodyData);
						}

						if (PhysicsAsset->SkeletalBodySetups.IsValidIndex(BodyIndex))
						{
							if (UBodySetup* TargetBodySetup = PhysicsAsset->SkeletalBodySetups[BodyIndex])
							{
								check(TargetBodySetup->BoneName == PastedBodySetup->BoneName);
								TargetBodySetup->Modify();
								TargetBodySetup->CopyBodyPropertiesFrom(PastedBodySetup);
								++OutNumPastedBodies;
							}
						}
					}

					// now let's process the constraints
					OutNumPastedConstraints = 0;
					for (const UPhysicsConstraintTemplate* PastedConstraintTemplate : Factory.NewConstraintTemplates)
					{
						FName ConstraintUniqueName = PastedConstraintTemplate->DefaultInstance.JointName;

						// search for a matching constraint by bone names
						const int32 ConstraintIndexByBones = PhysicsAsset->FindConstraintIndex(PastedConstraintTemplate->DefaultInstance.ConstraintBone1, PastedConstraintTemplate->DefaultInstance.ConstraintBone2);
						const int32 ConstraintIndexByJointName = PhysicsAsset->FindConstraintIndex(ConstraintUniqueName);

						// If the indices are not matching we need to generate a new unique name for the constraint
						if (ConstraintIndexByBones != ConstraintIndexByJointName)
						{
							ConstraintUniqueName = *MakeUniqueNewConstraintName();
						}

						int32 ConstraintIndex = ConstraintIndexByBones;
						if (ConstraintIndex == INDEX_NONE)
						{
							// none found, create a brand new one 
							ConstraintIndex = FPhysicsAssetUtils::CreateNewConstraint(PhysicsAsset, ConstraintUniqueName);
							check(ConstraintIndex != INDEX_NONE);
						}

						if (PhysicsAsset->ConstraintSetup.IsValidIndex(ConstraintIndex))
						{
							if (UPhysicsConstraintTemplate* TargetConstraintTemplate = PhysicsAsset->ConstraintSetup[ConstraintIndex])
							{
								TargetConstraintTemplate->Modify();

								// keep the existing instance as we want to keep some of its data 
								FConstraintInstance ExistingInstance = TargetConstraintTemplate->DefaultInstance;

								TargetConstraintTemplate->DefaultInstance.CopyConstraintParamsFrom(&PastedConstraintTemplate->DefaultInstance);

								TargetConstraintTemplate->DefaultInstance.JointName = ConstraintUniqueName;
								TargetConstraintTemplate->DefaultInstance.ConstraintIndex = ConstraintIndex;
								TargetConstraintTemplate->DefaultInstance.ConstraintHandle = ExistingInstance.ConstraintHandle;
								TargetConstraintTemplate->UpdateProfileInstance();
								++OutNumPastedConstraints;
							}
						}
					}
				}
			}
			// Remove the temp package from the root now that it has served its purpose
			TempPackage->RemoveFromRoot();

			RefreshPhysicsAssetChange(PhysicsAsset);
			ClearSelectedBody();	//paste can change the primitives on our selected bodies. There's probably a way to properly update this, but for now just deselect
			ClearSelectedConstraints();	//paste can change the primitives on our selected bodies. There's probably a way to properly update this, but for now just deselect
			BroadcastPreviewChanged();
			BroadcastHierarchyChanged();
		}
	}
}

void FPhysicsAssetEditorSharedData::CopyBodyProperties()
{
	check(SelectedBodies.Num() == 1);
	CopyToClipboard(SharedDataConstants::BodyType, PhysicsAsset->SkeletalBodySetups[GetSelectedBody()->Index]);
}

void FPhysicsAssetEditorSharedData::PasteBodyProperties()
{
	// Can't do this while simulating!
	if (bRunningSimulation)
	{
		return;
	}

	UPhysicsAsset* SourceAsset = nullptr;
	UObject* SourceBodySetup = nullptr;
	int32 SourceBodyIndex = 0;

	if(!PasteFromClipboard(SharedDataConstants::BodyType, SourceAsset, SourceBodySetup))
	{
		return;
	}

	const UBodySetup* CopiedBodySetup = Cast<UBodySetup>(SourceBodySetup);

	// Must have two valid bodies (which are different)
	if(CopiedBodySetup == NULL)
	{
		return;
	}

	if(SelectedBodies.Num() > 0)
	{
		const FScopedTransaction Transaction( NSLOCTEXT("PhysicsAssetEditor", "PasteBodyProperties", "Paste Body Properties") );

		PhysicsAsset->Modify();

		for(int32 i=0; i<SelectedBodies.Num(); ++i)
		{
			UBodySetup* ToBodySetup = PhysicsAsset->SkeletalBodySetups[SelectedBodies[i].Index];
			ToBodySetup->Modify();
			ToBodySetup->CopyBodyPropertiesFrom(CopiedBodySetup);
		}
	
		ClearSelectedBody();	//paste can change the primitives on our selected bodies. There's probably a way to properly update this, but for now just deselect
		BroadcastPreviewChanged();
	}
}

bool FPhysicsAssetEditorSharedData::WeldSelectedBodies(bool bWeld /* = true */)
{
	bool bCanWeld = false;
	if (bRunningSimulation)
	{
		return false;
	}

	if(SelectedBodies.Num() <= 1)
	{
		return false;
	}

	USkeletalMesh* EditorSkelMesh = PhysicsAsset->GetPreviewMesh();
	if(EditorSkelMesh == nullptr)
	{
		return false;
	}

	//we only support two body weld
	int BodyIndex0 = 0;
	int BodyIndex1 = INDEX_NONE;

	for(int32 i=1; i<SelectedBodies.Num(); ++i)
	{
		if(SelectedBodies[BodyIndex0].Index == SelectedBodies[i].Index)
		{
			continue;
		}

		if(BodyIndex1== INDEX_NONE)
		{
			BodyIndex1 = i;
		}else
		{
			if(SelectedBodies[BodyIndex1].Index != SelectedBodies[i].Index)
			{
				return false;
			}
		}
	}

	//need to weld bodies not primitives
	if(BodyIndex1 == INDEX_NONE)
	{
		return false;
	}

	const FSelection& Body0 = SelectedBodies[BodyIndex0];
	const FSelection& Body1 = SelectedBodies[BodyIndex1];

	FName Bone0Name = PhysicsAsset->SkeletalBodySetups[Body0.Index]->BoneName;
	int32 Bone0Index = EditorSkelMesh->GetRefSkeleton().FindBoneIndex(Bone0Name);
	check(Bone0Index != INDEX_NONE);

	FName Bone1Name = PhysicsAsset->SkeletalBodySetups[Body1.Index]->BoneName;
	int32 Bone1Index = EditorSkelMesh->GetRefSkeleton().FindBoneIndex(Bone1Name);
	check(Bone1Index != INDEX_NONE);

	int32 Bone0ParentIndex = EditorSkelMesh->GetRefSkeleton().GetParentIndex(Bone0Index);
	int32 Bone1ParentIndex = EditorSkelMesh->GetRefSkeleton().GetParentIndex(Bone1Index);

	int ParentBodyIndex = INDEX_NONE;
	int ChildBodyIndex = INDEX_NONE;
	FName ParentBoneName;
	EAggCollisionShape::Type ParentPrimitiveType = EAggCollisionShape::Unknown;
	EAggCollisionShape::Type ChildPrimitiveType = EAggCollisionShape::Unknown;
	int32 ParentPrimitiveIndex = INDEX_NONE;
	int32 ChildPrimitiveIndex = INDEX_NONE;

	if (PhysicsAsset->FindControllingBodyIndex(EditorSkelMesh, Bone1ParentIndex) == Body0.Index)
	{
		ParentBodyIndex = Body0.Index;
		ParentBoneName = Bone0Name;
		ChildBodyIndex = Body1.Index;
		ParentPrimitiveType = Body0.PrimitiveType;
		ChildPrimitiveType = Body1.PrimitiveType;
		ParentPrimitiveIndex = Body0.PrimitiveIndex;
		//Child geoms get appended so just add it. This is kind of a hack but this whole indexing scheme needs to be rewritten anyway
		ChildPrimitiveIndex = Body1.PrimitiveIndex + PhysicsAsset->SkeletalBodySetups[Body0.Index]->AggGeom.GetElementCount(ChildPrimitiveType);

		bCanWeld = true;
	}else if(PhysicsAsset->FindControllingBodyIndex(EditorSkelMesh, Bone0ParentIndex) == Body1.Index)
	{
		ParentBodyIndex = Body1.Index;
		ParentBoneName = Bone1Name;
		ChildBodyIndex = Body0.Index;
		ParentPrimitiveType = Body1.PrimitiveType;
		ChildPrimitiveType = Body0.PrimitiveType;
		ParentPrimitiveIndex = Body1.PrimitiveIndex;
		//Child geoms get appended so just add it. This is kind of a hack but this whole indexing scheme needs to be rewritten anyway
		ChildPrimitiveIndex = Body0.PrimitiveIndex + PhysicsAsset->SkeletalBodySetups[Body1.Index]->AggGeom.GetElementCount(ChildPrimitiveType);

		bCanWeld = true;
	}

	//function is used for the action and the check
	if(bWeld == false)
	{
		return bCanWeld;
	}

	check(ParentBodyIndex != INDEX_NONE);
	check(ChildBodyIndex != INDEX_NONE);

	{
		const FScopedTransaction Transaction( NSLOCTEXT("UnrealEd", "WeldBodies", "Weld Bodies") );

		// .. the asset itself..
		PhysicsAsset->Modify();

		// .. the parent and child bodies..
		PhysicsAsset->SkeletalBodySetups[ParentBodyIndex]->Modify();
		PhysicsAsset->SkeletalBodySetups[ChildBodyIndex]->Modify();

		// .. and any constraints of the 'child' body..
		TArray<int32>	Constraints;
		PhysicsAsset->BodyFindConstraints(ChildBodyIndex, Constraints);

		for (int32 i = 0; i <Constraints.Num(); ++i)
		{
			int32 ConstraintIndex = Constraints[i];
			PhysicsAsset->ConstraintSetup[ConstraintIndex]->Modify();
		}

		// Do the actual welding
		FPhysicsAssetUtils::WeldBodies(PhysicsAsset, ParentBodyIndex, ChildBodyIndex, EditorSkelComp);
	}

	// update the tree
	BroadcastHierarchyChanged();

	// Just to be safe - deselect any selected constraints
	ClearSelectedConstraints();
	ClearSelectedBody(); // Previous selection is invalid because child no longer has same index.

	int32 BodyIndex = PhysicsAsset->FindBodyIndex(ParentBoneName);
	FSelection SelectionParent(BodyIndex, ParentPrimitiveType, ParentPrimitiveIndex);
	SetSelectedBody(SelectionParent, true); // This redraws the viewport as well...

	FSelection SelectionChild(BodyIndex, ChildPrimitiveType, ChildPrimitiveIndex);
	SetSelectedBody(SelectionChild, true); // This redraws the viewport as well...

	RefreshPhysicsAssetChange(PhysicsAsset);
	return true;
}


void FPhysicsAssetEditorSharedData::InitConstraintSetup(UPhysicsConstraintTemplate* ConstraintSetup, int32 ChildBodyIndex, int32 ParentBodyIndex)
{
	check(ConstraintSetup);

	ConstraintSetup->Modify(false);

	UBodySetup* ChildBodySetup = PhysicsAsset->SkeletalBodySetups[ ChildBodyIndex ];
	UBodySetup* ParentBodySetup = PhysicsAsset->SkeletalBodySetups[ ParentBodyIndex ];
	check(ChildBodySetup && ParentBodySetup);

	// Place joint at origin of child
	ConstraintSetup->DefaultInstance.ConstraintBone1 = ChildBodySetup->BoneName;
	ConstraintSetup->DefaultInstance.ConstraintBone2 = ParentBodySetup->BoneName;
	SnapConstraintToBone(ConstraintSetup->DefaultInstance);

	ConstraintSetup->SetDefaultProfile(ConstraintSetup->DefaultInstance);

	// Disable collision between constrained bodies by default.
	SetCollisionBetween(ChildBodyIndex, ParentBodyIndex, false);
}

void FPhysicsAssetEditorSharedData::MakeNewBody(int32 NewBoneIndex, bool bAutoSelect)
{
	USkeletalMesh* EditorSkelMesh = PhysicsAsset->GetPreviewMesh();
	if(EditorSkelMesh == nullptr)
	{
		return;
	}
	PhysicsAsset->Modify();

	FName NewBoneName = EditorSkelMesh->GetRefSkeleton().GetBoneName(NewBoneIndex);

	// If this body is already physical, remove the current body
	int32 NewBodyIndex = PhysicsAsset->FindBodyIndex(NewBoneName);
	if (NewBodyIndex != INDEX_NONE)
	{
		DeleteBody(NewBodyIndex, false);
	}

	// Find body that currently controls this bone.
	int32 ParentBodyIndex = PhysicsAsset->FindControllingBodyIndex(EditorSkelMesh, NewBoneIndex);

	const FPhysAssetCreateParams& NewBodyData = GetDefault<UPhysicsAssetGenerationSettings>()->CreateParams;

	// Create the physics body.
	NewBodyIndex = FPhysicsAssetUtils::CreateNewBody(PhysicsAsset, NewBoneName, NewBodyData);
	UBodySetup* BodySetup = PhysicsAsset->SkeletalBodySetups[ NewBodyIndex ];
	check(BodySetup->BoneName == NewBoneName);
	
	BodySetup->Modify();

	bool bCreatedBody = false;
	// Create a new physics body for this bone.
	if (NewBodyData.VertWeight == EVW_DominantWeight)
	{
		bCreatedBody = FPhysicsAssetUtils::CreateCollisionFromBone(BodySetup, EditorSkelMesh, NewBoneIndex, NewBodyData, DominantWeightBoneInfos[NewBoneIndex]);
	}
	else
	{
		bCreatedBody = FPhysicsAssetUtils::CreateCollisionFromBone(BodySetup, EditorSkelMesh, NewBoneIndex, NewBodyData, AnyWeightBoneInfos[NewBoneIndex]);
	}

	if (bCreatedBody == false)
	{
		FPhysicsAssetUtils::DestroyBody(PhysicsAsset, NewBodyIndex);
		return;
	}

	// name the new created primitives
	AutoNameAllPrimitives(NewBodyIndex, NewBodyData.GeomType);

	// Check if the bone of the new body has any physical children bones
	for (int32 i = 0; i < EditorSkelMesh->GetRefSkeleton().GetRawBoneNum(); ++i)
	{
		if (EditorSkelMesh->GetRefSkeleton().BoneIsChildOf(i, NewBoneIndex))
		{
			const int32 ChildBodyIndex = PhysicsAsset->FindBodyIndex(EditorSkelMesh->GetRefSkeleton().GetBoneName(i));
			
			// If the child bone is physical, it may require fixing up in regards to constraints
			if (ChildBodyIndex != INDEX_NONE)
			{
				UBodySetup* ChildBody = PhysicsAsset->SkeletalBodySetups[ ChildBodyIndex ];
				check(ChildBody);

				int32 ConstraintIndex = PhysicsAsset->FindConstraintIndex(ChildBody->BoneName);
				
				// If the child body is not constrained already, create a new constraint between
				// the child body and the new body
				// @todo: This isn't quite right. It is possible that the child constraint's parent body is not our parent body. 
				// This can happen in a couple ways:
				// - the user altered the child constraint to attach to a different parent bond
				// - a new bone was added. E.g., add bone at root of hierarchy. Import mesh with new bone. Add body to root bone.
				// So, if this happens we need to decide if we should leave the old constraint there and add a new one, or commandeer the
				// constraint. If the former, we should probably change a constraint to a "User" constraint when they change its bones.
				// We are currently doing the latter...
				if (ConstraintIndex == INDEX_NONE)
				{
					ConstraintIndex = FPhysicsAssetUtils::CreateNewConstraint(PhysicsAsset, ChildBody->BoneName);
					check(ConstraintIndex != INDEX_NONE);
				}
				// If there's a pre-existing constraint, see if it needs to be fixed up
				else
				{
					UPhysicsConstraintTemplate* ExistingConstraintSetup = PhysicsAsset->ConstraintSetup[ ConstraintIndex ];
					check(ExistingConstraintSetup);
					
					const int32 ExistingConstraintBoneIndex = EditorSkelMesh->GetRefSkeleton().FindBoneIndex(ExistingConstraintSetup->DefaultInstance.ConstraintBone2);
					check(ExistingConstraintBoneIndex != INDEX_NONE);

					// If the constraint exists between two child bones, then no fix up is required
					if (EditorSkelMesh->GetRefSkeleton().BoneIsChildOf(ExistingConstraintBoneIndex, NewBoneIndex))
					{
						continue;
					}

					// If the constraint isn't between two child bones, then it is between a physical bone higher in the bone
					// hierarchy than the new bone, so it needs to be fixed up by setting the constraint to point to the new bone
					// instead. Additionally, collision needs to be re-enabled between the child bone and the identified "grandparent"
					// bone.
					const int32 ExistingConstraintBodyIndex = PhysicsAsset->FindBodyIndex(ExistingConstraintSetup->DefaultInstance.ConstraintBone2);
					check(ExistingConstraintBodyIndex != INDEX_NONE);

					// See above comments about the child constraint's parent not necessarily being our parent...
					if (ExistingConstraintBodyIndex == ParentBodyIndex)
					{
						SetCollisionBetween(ChildBodyIndex, ExistingConstraintBodyIndex, true);
					}
				}

				UPhysicsConstraintTemplate* ChildConstraintSetup = PhysicsAsset->ConstraintSetup[ ConstraintIndex ];
				check(ChildConstraintSetup);

				InitConstraintSetup(ChildConstraintSetup, ChildBodyIndex, NewBodyIndex);
			}
		}
	}

	// If we have a physics parent, create a joint to it.
	if (ParentBodyIndex != INDEX_NONE)
	{
		const int32 NewConstraintIndex = FPhysicsAssetUtils::CreateNewConstraint(PhysicsAsset, NewBoneName);
		UPhysicsConstraintTemplate* ConstraintSetup = PhysicsAsset->ConstraintSetup[ NewConstraintIndex ];
		check(ConstraintSetup);

		InitConstraintSetup(ConstraintSetup, NewBodyIndex, ParentBodyIndex);
	}

	// update the tree
	BroadcastHierarchyChanged();

	if (bAutoSelect)
	{
		SetSelectedBodyAnyPrim(NewBodyIndex, true);
	}
	

	RefreshPhysicsAssetChange(PhysicsAsset);
}

FString FPhysicsAssetEditorSharedData::MakeUniqueNewConstraintName()
{
	// Make a new unique name for this constraint
	int32 Index = 0;
	FString BaseConstraintName(TEXT("UserConstraint"));
	FString ConstraintName = BaseConstraintName;
	while (PhysicsAsset->FindConstraintIndex(*ConstraintName) != INDEX_NONE)
	{
		ConstraintName = FString::Printf(TEXT("%s_%d"), *BaseConstraintName, Index++);
	}
	return ConstraintName;
}

void FPhysicsAssetEditorSharedData::MakeNewConstraints(int32 ParentBodyIndex, const TArray<int32>& ChildBodyIndices)
{
	// check we have valid bodies
	check(ParentBodyIndex < PhysicsAsset->SkeletalBodySetups.Num());

	TArray<int32> NewlyCreatedConstraints;

	for (const int32 ChildBodyIndex : ChildBodyIndices)
	{
		check(ChildBodyIndex < PhysicsAsset->SkeletalBodySetups.Num());

		// Make a new unique name for this constraint
		FString ConstraintName = MakeUniqueNewConstraintName();

		// Create new constraint with a name not related to a bone, so it wont get auto managed in code that creates new bodies
		const int32 NewConstraintIndex = FPhysicsAssetUtils::CreateNewConstraint(PhysicsAsset, *ConstraintName);
		UPhysicsConstraintTemplate* ConstraintSetup = PhysicsAsset->ConstraintSetup[NewConstraintIndex];
		check(ConstraintSetup);

		NewlyCreatedConstraints.Add(NewConstraintIndex);

		InitConstraintSetup(ConstraintSetup, ChildBodyIndex, ParentBodyIndex);
	}

	ClearSelectedConstraints();
	SetSelectedConstraints(NewlyCreatedConstraints, true);

	// update the tree
	BroadcastHierarchyChanged();
	RefreshPhysicsAssetChange(PhysicsAsset);

	BroadcastSelectionChanged();
}

void FPhysicsAssetEditorSharedData::MakeNewConstraint(int32 ParentBodyIndex, int32 ChildBodyIndex)
{
	MakeNewConstraints(ParentBodyIndex, { ChildBodyIndex });
}

void FPhysicsAssetEditorSharedData::SetConstraintRelTM(const FPhysicsAssetEditorSharedData::FSelection* Constraint, const FTransform& RelTM)
{
	USkeletalMesh* EditorSkelMesh = PhysicsAsset->GetPreviewMesh();
	if(EditorSkelMesh == nullptr)
	{
		return;
	}

	FTransform WParentFrame = GetConstraintWorldTM(Constraint, EConstraintFrame::Frame2);
	FTransform WNewChildFrame = RelTM * WParentFrame;

	UPhysicsConstraintTemplate* ConstraintSetup = PhysicsAsset->ConstraintSetup[Constraint->Index];
	ConstraintSetup->Modify();

	// Get child bone transform
	int32 BoneIndex = EditorSkelMesh->GetRefSkeleton().FindBoneIndex(ConstraintSetup->DefaultInstance.ConstraintBone1);
	if (BoneIndex != INDEX_NONE)
	{
		FTransform BoneTM = EditorSkelComp->GetBoneTransform(BoneIndex);
		BoneTM.RemoveScaling();

		ConstraintSetup->DefaultInstance.SetRefFrame(EConstraintFrame::Frame1, WNewChildFrame.GetRelativeTransform(BoneTM));
	}
}

void FPhysicsAssetEditorSharedData::SnapConstraintToBone(int32 ConstraintIndex)
{
	UPhysicsConstraintTemplate* ConstraintSetup = PhysicsAsset->ConstraintSetup[ConstraintIndex];
	ConstraintSetup->Modify();
	SnapConstraintToBone(ConstraintSetup->DefaultInstance);
}

void FPhysicsAssetEditorSharedData::SnapConstraintToBone(FConstraintInstance& ConstraintInstance)
{
	USkeletalMesh* EditorSkelMesh = PhysicsAsset->GetPreviewMesh();
	if(EditorSkelMesh == nullptr)
	{
		return;
	}

	const int32 BoneIndex1 = EditorSkelMesh->GetRefSkeleton().FindBoneIndex(ConstraintInstance.ConstraintBone1);
	const int32 BoneIndex2 = EditorSkelMesh->GetRefSkeleton().FindBoneIndex(ConstraintInstance.ConstraintBone2);

	check(BoneIndex1 != INDEX_NONE);
	check(BoneIndex2 != INDEX_NONE);

	const FTransform BoneTransform1 = EditorSkelComp->GetBoneTransform(BoneIndex1);
	const FTransform BoneTransform2 = EditorSkelComp->GetBoneTransform(BoneIndex2);

	// Bone transforms are world space, and frame transforms are local space (local to bones).
	// Frame 1 is the child frame, and set to identity.
	// Frame 2 is the parent frame, and needs to be set relative to Frame1.
	ConstraintInstance.SetRefFrame(EConstraintFrame::Frame2, BoneTransform1.GetRelativeTransform(BoneTransform2));
	ConstraintInstance.SetRefFrame(EConstraintFrame::Frame1, FTransform::Identity);
}

void FPhysicsAssetEditorSharedData::CopyConstraintProperties()
{
	check(SelectedConstraints.Num() == 1);
	CopyToClipboard(SharedDataConstants::ConstraintType, PhysicsAsset->ConstraintSetup[GetSelectedConstraint()->Index]);
}

void FPhysicsAssetEditorSharedData::PasteConstraintProperties()
{
	UPhysicsAsset* SourceAsset = nullptr;
	UObject* SourceConstraint;

	if(!PasteFromClipboard(SharedDataConstants::ConstraintType, SourceAsset, SourceConstraint))
	{
		return;
	}

	const UPhysicsConstraintTemplate* FromConstraintSetup = Cast<UPhysicsConstraintTemplate>(SourceConstraint);

	if(FromConstraintSetup && SelectedConstraints.Num() > 0)
	{
		const FScopedTransaction Transaction(NSLOCTEXT("PhysicsAssetEditor", "PasteConstraintProperties", "Paste Constraint Properties"));

		for(int32 i=0; i<SelectedConstraints.Num(); ++i)
		{
			UPhysicsConstraintTemplate* ToConstraintSetup = PhysicsAsset->ConstraintSetup[SelectedConstraints[i].Index];
			CopyConstraintProperties(FromConstraintSetup, ToConstraintSetup, /*bKeepOriginalRotation=*/true);
		}
	}
}

void CycleMatrixRows(FMatrix* TM)
{
	float Tmp[3];

	Tmp[0]		= TM->M[0][0];	Tmp[1]		= TM->M[0][1];	Tmp[2]		= TM->M[0][2];
	TM->M[0][0] = TM->M[1][0];	TM->M[0][1] = TM->M[1][1];	TM->M[0][2] = TM->M[1][2];
	TM->M[1][0] = TM->M[2][0];	TM->M[1][1] = TM->M[2][1];	TM->M[1][2] = TM->M[2][2];
	TM->M[2][0] = Tmp[0];		TM->M[2][1] = Tmp[1];		TM->M[2][2] = Tmp[2];
}

void FPhysicsAssetEditorSharedData::CycleCurrentConstraintOrientation()
{
	const FScopedTransaction Transaction( LOCTEXT("CycleCurrentConstraintOrientation", "Cycle Current Constraint Orientation") );

	for(int32 i=0; i<SelectedConstraints.Num(); ++i)
	{
		UPhysicsConstraintTemplate* ConstraintTemplate = PhysicsAsset->ConstraintSetup[SelectedConstraints[i].Index];
		ConstraintTemplate->Modify();
		FMatrix ConstraintTransform = ConstraintTemplate->DefaultInstance.GetRefFrame(EConstraintFrame::Frame2).ToMatrixWithScale();
		FTransform WParentFrame = GetConstraintWorldTM(&SelectedConstraints[i], EConstraintFrame::Frame2);
		FTransform WChildFrame = GetConstraintWorldTM(&SelectedConstraints[i], EConstraintFrame::Frame1);
		FTransform RelativeTransform = WChildFrame * WParentFrame.Inverse();

		CycleMatrixRows(&ConstraintTransform);

		ConstraintTemplate->DefaultInstance.SetRefFrame(EConstraintFrame::Frame2, FTransform(ConstraintTransform));
		SetSelectedConstraintRelTM(RelativeTransform);
	}
}

void FPhysicsAssetEditorSharedData::CycleCurrentConstraintActive()
{
	const FScopedTransaction Transaction( LOCTEXT("CycleCurrentConstraintActive", "Cycle Current Constraint Active") );

	for(int32 i=0; i<SelectedConstraints.Num(); ++i)
	{
		UPhysicsConstraintTemplate* ConstraintTemplate = PhysicsAsset->ConstraintSetup[SelectedConstraints[i].Index];
		ConstraintTemplate->Modify();
		FConstraintInstance & DefaultInstance = ConstraintTemplate->DefaultInstance;

		if(DefaultInstance.GetAngularSwing1Motion() != ACM_Limited && DefaultInstance.GetAngularSwing2Motion() != ACM_Limited)
		{
			DefaultInstance.SetAngularSwing1Motion(ACM_Limited);
			DefaultInstance.SetAngularSwing2Motion(ACM_Locked);
			DefaultInstance.SetAngularTwistMotion(ACM_Locked);
		}else if(DefaultInstance.GetAngularSwing2Motion() != ACM_Limited && DefaultInstance.GetAngularTwistMotion() != ACM_Limited)
		{
			DefaultInstance.SetAngularSwing1Motion(ACM_Locked);
			DefaultInstance.SetAngularSwing2Motion(ACM_Limited);
			DefaultInstance.SetAngularTwistMotion(ACM_Locked);
		}else
		{
			DefaultInstance.SetAngularSwing1Motion(ACM_Locked);
			DefaultInstance.SetAngularSwing2Motion(ACM_Locked);
			DefaultInstance.SetAngularTwistMotion(ACM_Limited);
		}
		
		ConstraintTemplate->UpdateProfileInstance();
	}
}

void FPhysicsAssetEditorSharedData::ToggleConstraint(EPhysicsAssetEditorConstraintType Constraint)
{
	const FScopedTransaction Transaction( LOCTEXT("ToggleConstraintTypeLock", "Toggle Constraint Type Lock") );

	for(int32 i=0; i<SelectedConstraints.Num(); ++i)
	{
		UPhysicsConstraintTemplate* ConstraintTemplate = PhysicsAsset->ConstraintSetup[GetSelectedConstraint()->Index];
		ConstraintTemplate->Modify();
		FConstraintInstance & DefaultInstance = ConstraintTemplate->DefaultInstance;

		if(Constraint == PCT_Swing1)
		{
			DefaultInstance.SetAngularSwing1Motion(DefaultInstance.GetAngularSwing1Motion() == ACM_Limited ? ACM_Locked : ACM_Limited);
		}else if(Constraint == PCT_Swing2)
		{
			DefaultInstance.SetAngularSwing2Motion(DefaultInstance.GetAngularSwing2Motion() == ACM_Limited ? ACM_Locked : ACM_Limited);
		}else
		{
			DefaultInstance.SetAngularTwistMotion(DefaultInstance.GetAngularTwistMotion() == ACM_Limited ? ACM_Locked : ACM_Limited);
		}
		
		ConstraintTemplate->UpdateProfileInstance();
	}
}

bool FPhysicsAssetEditorSharedData::IsAngularConstraintLocked(EPhysicsAssetEditorConstraintType Constraint) const
{
	bool bLocked = false;
	bool bSame = false;

	for(int32 i = 0; i < SelectedConstraints.Num(); ++i)
	{
		UPhysicsConstraintTemplate* ConstraintTemplate = PhysicsAsset->ConstraintSetup[GetSelectedConstraint()->Index];
		FConstraintInstance & DefaultInstance = ConstraintTemplate->DefaultInstance;

		if(Constraint == PCT_Swing1)
		{
			bLocked |= DefaultInstance.GetAngularSwing1Motion() == ACM_Locked;
		}
		else if(Constraint == PCT_Swing2)
		{
			bLocked |= DefaultInstance.GetAngularSwing2Motion() == ACM_Locked;
		}
		else
		{
			bLocked |= DefaultInstance.GetAngularTwistMotion() == ACM_Locked;
		}
	}

	return bLocked;
}


void FPhysicsAssetEditorSharedData::DeleteBody(int32 DelBodyIndex, bool bRefreshComponent)
{
	USkeletalMesh* EditorSkelMesh = PhysicsAsset->GetPreviewMesh();
	if(EditorSkelMesh == nullptr)
	{
		return;
	}

	const FScopedTransaction Transaction( NSLOCTEXT("UnrealEd", "DeleteBody", "Delete Body") );

	// The physics asset and default instance..
	PhysicsAsset->Modify();

	// .. the body..
	UBodySetup * BodySetup = PhysicsAsset->SkeletalBodySetups[DelBodyIndex];
	BodySetup->Modify();	

	// .. and any constraints to the body.
	TArray<int32>	Constraints;
	PhysicsAsset->BodyFindConstraints(DelBodyIndex, Constraints);

	//we want to fixup constraints so that nearest child bodies get constraint with parent body
	TArray<int32> NearestBodiesBelow;
	PhysicsAsset->GetNearestBodyIndicesBelow(NearestBodiesBelow, BodySetup->BoneName, EditorSkelMesh);
	
	int32 BoneIndex = EditorSkelMesh->GetRefSkeleton().FindBoneIndex(BodySetup->BoneName);

	if (BoneIndex != INDEX_NONE)	//it's possible to delete bodies that have no bones. In this case just ignore all of this fixup code
	{
		int32 ParentBodyIndex = PhysicsAsset->FindParentBodyIndex(EditorSkelMesh, BoneIndex);

		UBodySetup * ParentBody = ParentBodyIndex != INDEX_NONE ? ToRawPtr(PhysicsAsset->SkeletalBodySetups[ParentBodyIndex]) : NULL;

		for (const int32 ConstraintIndex : Constraints)
		{
			UPhysicsConstraintTemplate * Constraint = PhysicsAsset->ConstraintSetup[ConstraintIndex];
			Constraint->Modify();

			if (ParentBody)
			{
				//for all constraints that contain a nearest child of this body, create a copy of the constraint between the child and parent
				for (const int32 BodyBelowIndex : NearestBodiesBelow)
				{
					UBodySetup * BodyBelow = PhysicsAsset->SkeletalBodySetups[BodyBelowIndex];

					if (Constraint->DefaultInstance.ConstraintBone1 == BodyBelow->BoneName)
					{
						int32 NewConstraintIndex = FPhysicsAssetUtils::CreateNewConstraint(PhysicsAsset, BodyBelow->BoneName, Constraint);
						UPhysicsConstraintTemplate * NewConstraint = PhysicsAsset->ConstraintSetup[NewConstraintIndex];
						InitConstraintSetup(NewConstraint, BodyBelowIndex, ParentBodyIndex);
					}
				}
			}
		}
	}

	// Clear clipboard if it was pointing to this body
	ConditionalClearClipboard(SharedDataConstants::BodyType, BodySetup);

	// Now actually destroy body. This will destroy any constraints associated with the body as well.
	FPhysicsAssetUtils::DestroyBody(PhysicsAsset, DelBodyIndex);

	// Select nothing.
	ClearSelectedBody();
	ClearSelectedConstraints();
	BroadcastHierarchyChanged();

	if (bRefreshComponent)
	{
		RefreshPhysicsAssetChange(PhysicsAsset);
	}
}

void FPhysicsAssetEditorSharedData::DeleteCurrentPrim()
{
	if (bRunningSimulation)
	{
		return;
	}

	if (!GetSelectedBody())
	{
		return;
	}

	// Make sure rendering is done - so we are not changing data being used by collision drawing.
	FlushRenderingCommands();

	//We will first get all the bodysetups we're interested in. The number of duplicates each bodysetup has tells us how many geoms are being deleted
	//We need to do this first because deleting will modify our selection
	TMap<UBodySetup *, TArray<FSelection>> BodySelectionMap;
	TArray<UBodySetup*> BodySetups;
	for(int32 i=0; i<SelectedBodies.Num(); ++i)
	{
		UBodySetup* BodySetup = PhysicsAsset->SkeletalBodySetups[SelectedBodies[i].Index];
		BodySelectionMap.FindOrAdd(BodySetup).Add(SelectedBodies[i]);
	}

	const FScopedTransaction Transaction( NSLOCTEXT("UnrealEd", "DeletePrimitive", "Delete Primitive") );

	for (TMap<UBodySetup*, TArray<FSelection> >::TConstIterator It(BodySelectionMap); It; ++It)
	{
		UBodySetup * BodySetup = It.Key();
		const TArray<FSelection> & SelectedPrimitives = It.Value();

		int32 SphereDeletedCount = 0;
		int32 BoxDeletedCount = 0;
		int32 SphylDeletedCount = 0;
		int32 ConvexDeletedCount = 0;
		int32 TaperedCapsuleDeletedCount = 0;

		for (int32 i = 0; i < SelectedPrimitives.Num(); ++i)
		{
			const FSelection& SelectedBody = SelectedPrimitives[i];
			int32 BodyIndex = PhysicsAsset->FindBodyIndex(BodySetup->BoneName);

			BodySetup->Modify();

			if (SelectedBody.PrimitiveType == EAggCollisionShape::Sphere)
			{
				BodySetup->AggGeom.SphereElems.RemoveAt(SelectedBody.PrimitiveIndex - (SphereDeletedCount++));
			}
			else if (SelectedBody.PrimitiveType == EAggCollisionShape::Box)
			{
				BodySetup->AggGeom.BoxElems.RemoveAt(SelectedBody.PrimitiveIndex - (BoxDeletedCount++));
			}
			else if (SelectedBody.PrimitiveType == EAggCollisionShape::Sphyl)
			{
				BodySetup->AggGeom.SphylElems.RemoveAt(SelectedBody.PrimitiveIndex - (SphylDeletedCount++));
			}
			else if (SelectedBody.PrimitiveType == EAggCollisionShape::Convex)
			{
				BodySetup->AggGeom.ConvexElems.RemoveAt(SelectedBody.PrimitiveIndex - (ConvexDeletedCount++));
				// Need to invalidate GUID in this case as cooked data must be updated
				BodySetup->InvalidatePhysicsData();
			}
			else if (SelectedBody.PrimitiveType == EAggCollisionShape::TaperedCapsule)
			{
				BodySetup->AggGeom.TaperedCapsuleElems.RemoveAt(SelectedBody.PrimitiveIndex - (TaperedCapsuleDeletedCount++));
			}

			// If this bone has no more geometry - remove it totally.
			if (BodySetup->AggGeom.GetElementCount() == 0)
			{
				check(i == SelectedPrimitives.Num() - 1);	//we should really only delete on last prim - only reason this is even in for loop is because of API needing body index
				if (BodyIndex != INDEX_NONE)
				{
					DeleteBody(BodyIndex, false);
				}
			}
		}
	}

	ClearSelectedBody(); // Will call UpdateViewport
	RefreshPhysicsAssetChange(PhysicsAsset);

	BroadcastHierarchyChanged();
}

FTransform FPhysicsAssetEditorSharedData::GetConstraintBodyTM(const UPhysicsConstraintTemplate* ConstraintSetup, EConstraintFrame::Type Frame) const
{
	if (ConstraintSetup == NULL)
	{
		return FTransform::Identity;
	}

	USkeletalMesh* EditorSkelMesh = PhysicsAsset->GetPreviewMesh();
	if(EditorSkelMesh == nullptr)
	{
		return FTransform::Identity;
	}

	int32 BoneIndex;
	if (Frame == EConstraintFrame::Frame1)
	{
		BoneIndex = EditorSkelMesh->GetRefSkeleton().FindBoneIndex(ConstraintSetup->DefaultInstance.ConstraintBone1);
	}
	else
	{
		BoneIndex = EditorSkelMesh->GetRefSkeleton().FindBoneIndex(ConstraintSetup->DefaultInstance.ConstraintBone2);
	}

	// If we couldn't find the bone - fall back to identity.
	if (BoneIndex == INDEX_NONE)
	{
		return FTransform::Identity;
	}
	else
	{
		FTransform BoneTM = EditorSkelComp->GetBoneTransform(BoneIndex);
		BoneTM.RemoveScaling();

		return BoneTM;
	}
}

FTransform FPhysicsAssetEditorSharedData::GetConstraintWorldTM(const UPhysicsConstraintTemplate* ConstraintSetup, EConstraintFrame::Type Frame, float Scale) const
{
	if (ConstraintSetup == NULL)
	{
		return FTransform::Identity;
	}

	USkeletalMesh* EditorSkelMesh = PhysicsAsset->GetPreviewMesh();
	if(EditorSkelMesh == nullptr)
	{
		return FTransform::Identity;
	}

	FVector Scale3D(Scale);

	int32 BoneIndex;
	FTransform LFrame = ConstraintSetup->DefaultInstance.GetRefFrame(Frame);
	if (Frame == EConstraintFrame::Frame1)
	{
		BoneIndex = EditorSkelMesh->GetRefSkeleton().FindBoneIndex(ConstraintSetup->DefaultInstance.ConstraintBone1);
	}
	else
	{
		BoneIndex = EditorSkelMesh->GetRefSkeleton().FindBoneIndex(ConstraintSetup->DefaultInstance.ConstraintBone2);
	}

	// If we couldn't find the bone - fall back to identity.
	if (BoneIndex == INDEX_NONE)
	{
		return FTransform::Identity;
	}
	else
	{
		FTransform BoneTM = EditorSkelComp->GetBoneTransform(BoneIndex);
		BoneTM.RemoveScaling();

		LFrame.ScaleTranslation(Scale3D);

		return LFrame * BoneTM;
	}
}

FTransform FPhysicsAssetEditorSharedData::GetConstraintMatrix(int32 ConstraintIndex, EConstraintFrame::Type Frame, float Scale) const
{
	UPhysicsConstraintTemplate* ConstraintSetup = PhysicsAsset->ConstraintSetup[ConstraintIndex];
	return GetConstraintWorldTM(ConstraintSetup, Frame, Scale);
}


FTransform FPhysicsAssetEditorSharedData::GetConstraintWorldTM(const FSelection* Constraint, EConstraintFrame::Type Frame) const
{
	int32 ConstraintIndex = Constraint ? Constraint->Index : INDEX_NONE;
	if (ConstraintIndex == INDEX_NONE)
	{
		return FTransform::Identity;
	}

	UPhysicsConstraintTemplate* ConstraintSetup = PhysicsAsset->ConstraintSetup[ConstraintIndex];
	return GetConstraintWorldTM(ConstraintSetup, Frame, 1.f);
}


void FPhysicsAssetEditorSharedData::DeleteCurrentConstraint()
{
	if (!GetSelectedConstraint())
	{
		return;
	}

	const FScopedTransaction Transaction( NSLOCTEXT("PhysicsAssetEditor", "DeleteConstraint", "Delete Constraint") );

	//Save indices before delete because delete modifies our Selected array
	TArray<int32> Indices;
	for(int32 i=0; i<SelectedConstraints.Num(); ++i)
	{
		ConditionalClearClipboard(SharedDataConstants::ConstraintType, PhysicsAsset->ConstraintSetup[SelectedConstraints[i].Index]);
		Indices.Add(SelectedConstraints[i].Index);
	}

	Indices.Sort();

	//These are indices into an array, we must remove it from greatest to smallest so that the indices don't shift
	for(int32 i=Indices.Num() - 1; i>= 0; --i)
	{
		PhysicsAsset->Modify();
		FPhysicsAssetUtils::DestroyConstraint(PhysicsAsset, Indices[i]);
	}
	
	ClearSelectedConstraints();

	BroadcastHierarchyChanged();
	BroadcastPreviewChanged();
}

void FPhysicsAssetEditorSharedData::ToggleSimulation()
{
	// don't start simulation if there are no bodies or if we are manipulating a body
	if (PhysicsAsset->SkeletalBodySetups.Num() == 0 || bManipulating)
	{
		return;  
	}

	EnableSimulation(!bRunningSimulation);
}

void FPhysicsAssetEditorSharedData::EnableSimulation(bool bEnableSimulation)
{
	// keep the EditorSkelComp animation asset if any set 
	UAnimationAsset* PreviewAnimationAsset = nullptr;
	if (EditorSkelComp->PreviewInstance)
	{
		PreviewAnimationAsset = EditorSkelComp->PreviewInstance->CurrentAsset;
	}

	if (bEnableSimulation)
	{
		// in Chaos, we have to manipulate the RBAN node in the Anim Instance (at least until we get SkelMeshComp implemented)
		const bool bUseRBANSolver = (PhysicsAsset->SolverType == EPhysicsAssetSolverType::RBAN);
		MouseHandle->SetAnimInstanceMode(bUseRBANSolver);

		if (!bUseRBANSolver)
		{
			// We should not already have an instance (destroyed when stopping sim).
			EditorSkelComp->SetCollisionEnabled(ECollisionEnabled::QueryAndPhysics);
			EditorSkelComp->SetSimulatePhysics(true);
			EditorSkelComp->ResetAllBodiesSimulatePhysics();
			EditorSkelComp->SetPhysicsBlendWeight(EditorOptions->PhysicsBlend);
			PhysicalAnimationComponent->SetSkeletalMeshComponent(EditorSkelComp);
			// Make it start simulating
			EditorSkelComp->WakeAllRigidBodies();
		}
		else
		{
			// Enable the PreviewInstance (containing the AnimNode_RigidBody)
			EditorSkelComp->SetAnimationMode(EAnimationMode::AnimationCustomMode);
			EditorSkelComp->InitAnim(true);

			// Disable main solver physics
			EditorSkelComp->SetAllBodiesSimulatePhysics(false);

			// make sure we enable the preview animation is any compatible with the skeleton
			if (PreviewAnimationAsset && EditorSkelComp->SkeletalMesh && PreviewAnimationAsset->GetSkeleton() == EditorSkelComp->SkeletalMesh->GetSkeleton())
			{
				EditorSkelComp->EnablePreview(true, PreviewAnimationAsset);
				EditorSkelComp->Play(true);
			}

			// Add the floor
			TSharedPtr<IPersonaPreviewScene> Scene = PreviewScene.Pin();
			if (Scene != nullptr)
			{
				UStaticMeshComponent* FloorMeshComponent = const_cast<UStaticMeshComponent*>(Scene->GetFloorMeshComponent());
				if ((FloorMeshComponent != nullptr) && (FloorMeshComponent->GetBodyInstance() != nullptr))
				{
					EditorSkelComp->CreateSimulationFloor(FloorMeshComponent->GetBodyInstance(), FloorMeshComponent->GetBodyInstance()->GetUnrealWorldTransform());
				}
			}
		}

		if(EditorOptions->bResetClothWhenSimulating)
		{
			EditorSkelComp->RecreateClothingActors();
		}
	}
	else
	{
		// Disable the PreviewInstance
		//EditorSkelComp->AnimScriptInstance = nullptr;
		//if(EditorSkelComp->GetAnimationMode() != EAnimationMode::AnimationSingleNode)
		{
			EditorSkelComp->SetAnimationMode(EAnimationMode::AnimationSingleNode);
		}

		// Stop any animation and clear node when stopping simulation.
		PhysicalAnimationComponent->SetSkeletalMeshComponent(nullptr);

		// Undo ends up recreating the anim script instance, so we need to remove it here (otherwise the AnimNode_RigidBody similation starts when we undo)
		EditorSkelComp->ClearAnimScriptInstance();

		EditorSkelComp->SetPhysicsBlendWeight(0.f);
		EditorSkelComp->ResetAllBodiesSimulatePhysics();
		EditorSkelComp->SetSimulatePhysics(false);
		ForceDisableSimulation();

		// Since simulation, actor location changes. Reset to identity 
		EditorSkelComp->SetWorldTransform(ResetTM);
		// Force an update of the skeletal mesh to get it back to ref pose
		EditorSkelComp->RefreshBoneTransforms();
	
		// restore the EditorSkelComp animation asset 
		if (PreviewAnimationAsset)
		{
			EditorSkelComp->EnablePreview(true, PreviewAnimationAsset);
		}

		BroadcastPreviewChanged();
	}

	bRunningSimulation = bEnableSimulation;
}

void FPhysicsAssetEditorSharedData::OpenNewBodyDlg()
{
	OpenNewBodyDlg(&NewBodyResponse);
}

void FPhysicsAssetEditorSharedData::OpenNewBodyDlg(EAppReturnType::Type* NewBodyResponse)
{
	TSharedRef<SWindow> ModalWindow = SNew(SWindow)
		.Title(LOCTEXT("NewAssetTitle", "New Physics Asset"))
		.SizingRule(ESizingRule::FixedSize)
		.ClientSize(FVector2D(400.0f, 400.0f))
		.SupportsMinimize(false) 
		.SupportsMaximize(false);

	TWeakPtr<SWindow> ModalWindowPtr = ModalWindow;

	ModalWindow->SetContent(
		CreateGenerateBodiesWidget(
			FSimpleDelegate::CreateLambda([ModalWindowPtr, NewBodyResponse]()
			{
				*NewBodyResponse = EAppReturnType::Ok;
				ModalWindowPtr.Pin()->RequestDestroyWindow();
			}),
			FSimpleDelegate::CreateLambda([ModalWindowPtr, NewBodyResponse]()
			{
				*NewBodyResponse = EAppReturnType::Cancel;
				ModalWindowPtr.Pin()->RequestDestroyWindow();
			}),
			true,
			LOCTEXT("CreateAsset", "Create Asset"),
			true
		));

	GEditor->EditorAddModalWindow(ModalWindow);
}

TSharedRef<SWidget> FPhysicsAssetEditorSharedData::CreateGenerateBodiesWidget(const FSimpleDelegate& InOnCreate, const FSimpleDelegate& InOnCancel, const TAttribute<bool>& InIsEnabled, const TAttribute<FText>& InCreateButtonText, bool bForNewAsset)
{
	FDetailsViewArgs DetailsViewArgs;
	DetailsViewArgs.NameAreaSettings = FDetailsViewArgs::HideNameArea;
	DetailsViewArgs.bHideSelectionTip = true;
	DetailsViewArgs.bAllowSearch = false;

	FPropertyEditorModule& PropertyEditorModule = FModuleManager::LoadModuleChecked<FPropertyEditorModule>("PropertyEditor");
	TSharedRef<IDetailsView> DetailsView = PropertyEditorModule.CreateDetailView(DetailsViewArgs);

	GetMutableDefault<UPhysicsAssetGenerationSettings>()->LoadConfig();
	DetailsView->SetObject(GetMutableDefault<UPhysicsAssetGenerationSettings>());
	DetailsView->OnFinishedChangingProperties().AddLambda([](const FPropertyChangedEvent& InEvent){ GetMutableDefault<UPhysicsAssetGenerationSettings>()->SaveConfig(); });

	return SNew(SVerticalBox)
		.IsEnabled(InIsEnabled)
		+SVerticalBox::Slot()
		.FillHeight(1.0f)
		[
			DetailsView
		]
		+SVerticalBox::Slot()
		.AutoHeight()
		[
			SNew(SBorder)
			.BorderImage(FAppStyle::Get().GetBrush("Brushes.Panel"))
			.VAlign(VAlign_Center)
			.HAlign(HAlign_Right)
			[
				SNew(SHorizontalBox)
				+SHorizontalBox::Slot()
				.Padding(2.0f)
				.AutoWidth()
				[
					SNew(SPrimaryButton)
					.Text(InCreateButtonText)
					.OnClicked_Lambda([InOnCreate]()
					{ 
						GetMutableDefault<UPhysicsAssetGenerationSettings>()->SaveConfig(); 
						InOnCreate.ExecuteIfBound(); 
						return FReply::Handled(); 
					})
					.ToolTipText(bForNewAsset ? 
								LOCTEXT("CreateAsset_Tooltip", "Create a new physics asset using these settings.") :
								LOCTEXT("GenerateBodies_Tooltip", "Generate new bodies and constraints. If bodies are selected then they will be replaced along with their constraints using the new settings, otherwise all bodies and constraints will be re-created"))
				]
				+SHorizontalBox::Slot()
				.Padding(2.0f)
				.AutoWidth()
				[
					SNew(SButton)
					.Visibility_Lambda([bForNewAsset](){ return bForNewAsset ? EVisibility::Visible : EVisibility::Collapsed; })
					.ButtonStyle(FAppStyle::Get(), "FlatButton")
					.ForegroundColor(FLinearColor::White)
					.ContentPadding(FMargin(6, 2))
					.OnClicked_Lambda([InOnCancel](){ InOnCancel.ExecuteIfBound(); return FReply::Handled(); })
					[
						SNew(STextBlock)
						.TextStyle(FAppStyle::Get(), "PhysicsAssetEditor.Tools.Font")
						.Text(LOCTEXT("Cancel", "Cancel"))
					]
				]
			]
		];
}

void FPhysicsAssetEditorSharedData::PostUndo()
{
	bool bInvalidSelection = false;

	for (int32 BodyIndex = 0; BodyIndex < SelectedBodies.Num() && bInvalidSelection == false; ++BodyIndex)
	{
		const FSelection& Selection = SelectedBodies[BodyIndex];
		if (PhysicsAsset->SkeletalBodySetups.Num() <= Selection.Index)
		{
			bInvalidSelection = true;
		}
		else
		{
			
			if (UBodySetup * BodySetup = PhysicsAsset->SkeletalBodySetups[Selection.Index])
			{
				switch (Selection.PrimitiveType)
				{
				case EAggCollisionShape::Box: bInvalidSelection = BodySetup->AggGeom.BoxElems.Num() <= Selection.PrimitiveIndex ? true : bInvalidSelection; break;
				case EAggCollisionShape::Convex: bInvalidSelection = BodySetup->AggGeom.ConvexElems.Num() <= Selection.PrimitiveIndex ? true : bInvalidSelection; break;
				case EAggCollisionShape::Sphere: bInvalidSelection = BodySetup->AggGeom.SphereElems.Num() <= Selection.PrimitiveIndex ? true : bInvalidSelection; break;
				case EAggCollisionShape::Sphyl: bInvalidSelection = BodySetup->AggGeom.SphylElems.Num() <= Selection.PrimitiveIndex ? true : bInvalidSelection; break;
				case EAggCollisionShape::TaperedCapsule: bInvalidSelection = BodySetup->AggGeom.TaperedCapsuleElems.Num() <= Selection.PrimitiveIndex ? true : bInvalidSelection; break;
				default: bInvalidSelection = true;
				}
			}
			else
			{
				bInvalidSelection = true;
			}
		}
	}

	for (int32 ConstraintIndex = 0; ConstraintIndex < SelectedConstraints.Num() && bInvalidSelection == false; ++ConstraintIndex)
	{
		const FSelection& Selection = SelectedConstraints[ConstraintIndex];
		if (PhysicsAsset->ConstraintSetup.Num() <= Selection.Index)
		{
			bInvalidSelection = true;
		}
	}

	if (bInvalidSelection)
	{
		// Clear selection before we undo. We don't transact the editor itself - don't want to have something selected that is then removed.
		ClearSelectedBody();
		ClearSelectedConstraints();
	}

	BroadcastPreviewChanged();
	BroadcastHierarchyChanged();
}

void FPhysicsAssetEditorSharedData::Redo()
{
	if (bRunningSimulation)
	{
		return;
	}

	ClearSelectedBody();
	ClearSelectedConstraints();

	GEditor->RedoTransaction();
	PhysicsAsset->UpdateBodySetupIndexMap();

	BroadcastPreviewChanged();
	BroadcastHierarchyChanged();
}

void FPhysicsAssetEditorSharedData::AddReferencedObjects(FReferenceCollector& Collector)
{
	Collector.AddReferencedObject(PhysicsAsset);
	Collector.AddReferencedObject(EditorSkelComp);
	Collector.AddReferencedObject(PhysicalAnimationComponent);
	Collector.AddReferencedObject(EditorOptions);
	Collector.AddReferencedObject(MouseHandle);

	if (PreviewScene != nullptr)
	{
		PreviewScene.Pin()->AddReferencedObjects(Collector);
	}
}

void FPhysicsAssetEditorSharedData::ForceDisableSimulation()
{
	// Reset simulation state of body instances so we dont actually simulate outside of 'simulation mode'
	for (int32 BodyIdx = 0; BodyIdx < EditorSkelComp->Bodies.Num(); ++BodyIdx)
	{
		if (FBodyInstance* BodyInst = EditorSkelComp->Bodies[BodyIdx])
		{
			if (UBodySetup* PhysAssetBodySetup = PhysicsAsset->SkeletalBodySetups[BodyIdx])
			{
				BodyInst->SetInstanceSimulatePhysics(false);
			}
		}
	}
}

void FPhysicsAssetEditorSharedData::UpdateClothPhysics()
{
	if(EditorSkelComp && EditorSkelComp->GetClothingSimulationInteractor())
	{
		EditorSkelComp->GetClothingSimulationInteractor()->PhysicsAssetUpdated();
	}
}

FPhysicsAssetRenderSettings* FPhysicsAssetEditorSharedData::GetRenderSettings() const
{
	return UPhysicsAssetRenderUtilities::GetSettings(PhysicsAsset);
}


#undef LOCTEXT_NAMESPACE