bool UEditorEngine::ReimportFbxAnimation( USkeleton* Skeleton, UAnimSequence* AnimSequence, UFbxAnimSequenceImportData* ImportData, const TCHAR* InFilename)
{
	check(Skeleton);

	GWarn->BeginSlowTask( LOCTEXT("ImportingFbxAnimations", "Importing FBX animations"), true );

	UnFbx::FFbxImporter* FbxImporter = UnFbx::FFbxImporter::GetInstance();
	// logger for all error/warnings
	// this one prints all messages that are stored in FFbxImporter	
	UnFbx::FFbxLoggerSetter Logger(FbxImporter);	
	const bool bPrevImportMorph = (AnimSequence->RawCurveData.FloatCurves.Num() > 0) ;

	if ( ImportData )
	{
		// Prepare the import options
		UFbxImportUI* ReimportUI = NewObject<UFbxImportUI>();
		ReimportUI->MeshTypeToImport = FBXIT_Animation;
		ReimportUI->bOverrideFullName = false;
		ReimportUI->AnimSequenceImportData = ImportData;

		ApplyImportUIToImportOptions(ReimportUI, *FbxImporter->ImportOptions);
	}
	else
	{
		FbxImporter->ImportOptions->ResetForReimportAnimation();	
	}

	if ( !FbxImporter->ImportFromFile( InFilename, FPaths::GetExtension( InFilename ) ) )
	{
		// Log the error message and fail the import.
		FbxImporter->FlushToTokenizedErrorMessage(EMessageSeverity::Error);

	}
	else
	{
		// Log the import message and import the mesh.
		FbxImporter->FlushToTokenizedErrorMessage(EMessageSeverity::Warning);


		const FString Filename( InFilename );

		// Get Mesh nodes array that bind to the skeleton system, then morph animation is imported.
		TArray<FbxNode*> FBXMeshNodeArray;
		FbxNode* SkeletonRoot = FbxImporter->FindFBXMeshesByBone(Skeleton->GetReferenceSkeleton().GetBoneName(0), true, FBXMeshNodeArray);

		if (!SkeletonRoot)
		{
			FbxImporter->AddTokenizedErrorMessage(FTokenizedMessage::Create(EMessageSeverity::Error, FText::Format(LOCTEXT("Error_CouldNotFindFbxTrack", "Mesh contains {0} bone as root but animation doesn't contain the root track.\nImport failed."), FText::FromName(Skeleton->GetReferenceSkeleton().GetBoneName(0)))), FFbxErrors::Animation_CouldNotFindTrack);

			FbxImporter->ReleaseScene();
			GWarn->EndSlowTask();
			return false;
		}

		// for now import all the time?
		bool bImportMorphTracks = true;
		// Check for blend shape curves that are not skinned.  Unskinned geometry can still contain morph curves
		if( bImportMorphTracks )
		{
			TArray<FbxNode*> MeshNodes;
			FbxImporter->FillFbxMeshArray( FbxImporter->Scene->GetRootNode(), MeshNodes, FbxImporter );

			for( int32 NodeIndex = 0; NodeIndex < MeshNodes.Num(); ++NodeIndex )
			{
				// Its possible the nodes already exist so make sure they are only added once
				FBXMeshNodeArray.AddUnique( MeshNodes[NodeIndex] );
			}
		}

		TArray<FbxNode*> SortedLinks;
		FbxImporter->RecursiveBuildSkeleton(SkeletonRoot, SortedLinks);

		if(SortedLinks.Num() == 0)
		{
			FbxImporter->AddTokenizedErrorMessage(FTokenizedMessage::Create(EMessageSeverity::Warning, LOCTEXT("Error_CouldNotBuildValidSkeleton", "Could not create a valid skeleton from the import data that matches the given Skeletal Mesh.  Check the bone names of both the Skeletal Mesh for this AnimSet and the animation data you are trying to import.")), FFbxErrors::Animation_CouldNotBuildSkeleton);
		}
		else
		{
			// find the correct animation based on import data
			FbxAnimStack* CurAnimStack = nullptr;
			
			//ignore the source animation name if there's only one animation in the file.
			//this is to make it easier for people who use content creation programs that only export one animation and/or ones that don't allow naming animations			
			if (FbxImporter->Scene->GetSrcObjectCount(FbxCriteria::ObjectType(FbxAnimStack::ClassId)) > 1 && !ImportData->SourceAnimationName.IsEmpty())
			{
				CurAnimStack = FbxCast<FbxAnimStack>(FbxImporter->Scene->FindSrcObject(FbxCriteria::ObjectType(FbxAnimStack::ClassId), TCHAR_TO_UTF8(*ImportData->SourceAnimationName), 0));
			}
			else
			{
				CurAnimStack = FbxCast<FbxAnimStack>(FbxImporter->Scene->GetSrcObject(FbxCriteria::ObjectType(FbxAnimStack::ClassId), 0));
			}
			
			if (CurAnimStack)
			{
				// set current anim stack
				int32 ResampleRate = DEFAULT_SAMPLERATE;
				if (FbxImporter->ImportOptions->bResample)
				{
					ResampleRate = FbxImporter->GetMaxSampleRate(SortedLinks, FBXMeshNodeArray);
				}
				FbxTimeSpan AnimTimeSpan = FbxImporter->GetAnimationTimeSpan(SortedLinks[0], CurAnimStack);
				// for now it's not importing morph - in the future, this should be optional or saved with asset
				if (FbxImporter->ValidateAnimStack(SortedLinks, FBXMeshNodeArray, CurAnimStack, ResampleRate, bImportMorphTracks, AnimTimeSpan))
				{
					FbxImporter->ImportAnimation( Skeleton, AnimSequence, Filename, SortedLinks, FBXMeshNodeArray, CurAnimStack, ResampleRate, AnimTimeSpan);
				}
			}
			else
			{
				// no track is found

				FbxImporter->AddTokenizedErrorMessage(FTokenizedMessage::Create(EMessageSeverity::Error, LOCTEXT("Error_CouldNotFindTrack", "Could not find needed track.")), FFbxErrors::Animation_CouldNotFindTrack);

				FbxImporter->ReleaseScene();
				GWarn->EndSlowTask();
				return false;
			}
		}
	}

	FbxImporter->ImportOptions->bImportMorph = bPrevImportMorph;
	FbxImporter->ReleaseScene();
	GWarn->EndSlowTask();

	return true;
}
	void ImportStaticMeshLOD( UStaticMesh* BaseStaticMesh, const FString& Filename, int32 LODLevel )
	{
		UE_LOG(LogExportMeshUtils, Log, TEXT("Fbx LOD loading"));
		// logger for all error/warnings
		// this one prints all messages that are stored in FFbxImporter
		// this function seems to get called outside of FBX factory
		UnFbx::FFbxImporter* FFbxImporter = UnFbx::FFbxImporter::GetInstance();
		UnFbx::FFbxLoggerSetter Logger(FFbxImporter);

		// don't import materials
		UnFbx::FBXImportOptions* ImportOptions = FFbxImporter->GetImportOptions();
		ImportOptions->bImportMaterials = false;
		ImportOptions->bImportTextures = false;

		if ( !FFbxImporter->ImportFromFile( *Filename, FPaths::GetExtension( Filename ) ) )
		{
			// Log the error message and fail the import.
			// @todo verify if the message works
			FFbxImporter->FlushToTokenizedErrorMessage(EMessageSeverity::Error);
		}
		else
		{
			FFbxImporter->FlushToTokenizedErrorMessage(EMessageSeverity::Warning);

			bool bUseLODs = true;
			int32 MaxLODLevel = 0;
			TArray< TArray<FbxNode*>* > LODNodeList;
			TArray<FString> LODStrings;

			// Create a list of LOD nodes
			PopulateFBXStaticMeshLODList(FFbxImporter, FFbxImporter->Scene->GetRootNode(), LODNodeList, MaxLODLevel, bUseLODs);

			// No LODs, so just grab all of the meshes in the file
			if (MaxLODLevel == 0)
			{
				bUseLODs = false;
				MaxLODLevel = BaseStaticMesh->GetNumLODs();

				// Create a list of meshes
				PopulateFBXStaticMeshLODList(FFbxImporter, FFbxImporter->Scene->GetRootNode(), LODNodeList, MaxLODLevel, bUseLODs);

				// Nothing found, error out
				if (LODNodeList.Num() == 0)
				{
					FFbxImporter->AddTokenizedErrorMessage(FTokenizedMessage::Create(EMessageSeverity::Error, FText(LOCTEXT("Prompt_NoMeshFound", "No meshes were found in file."))), FFbxErrors::Generic_Mesh_MeshNotFound);

					FFbxImporter->ReleaseScene();
					return;
				}
			}

			// Display the LOD selection dialog
			if (LODLevel > BaseStaticMesh->GetNumLODs())
			{
				// Make sure they don't manage to select a bad LOD index
				FFbxImporter->AddTokenizedErrorMessage(FTokenizedMessage::Create(EMessageSeverity::Warning, FText::Format(LOCTEXT("Prompt_InvalidLODIndex", "Invalid mesh LOD index {0}, as no prior LOD index exists!"), FText::AsNumber(LODLevel))), FFbxErrors::Generic_Mesh_LOD_InvalidIndex);
			}
			else
			{
				// Import mesh
				UStaticMesh* TempStaticMesh = NULL;
				TempStaticMesh = (UStaticMesh*)FFbxImporter->ImportStaticMeshAsSingle(GetTransientPackage(), *(LODNodeList[bUseLODs? LODLevel: 0]), NAME_None, RF_NoFlags, NULL, BaseStaticMesh, LODLevel);

				// Add imported mesh to existing model
				if( TempStaticMesh )
				{
					// Update mesh component
					BaseStaticMesh->MarkPackageDirty();

					// Import worked
					FNotificationInfo NotificationInfo(FText::GetEmpty());
					NotificationInfo.Text = FText::Format(LOCTEXT("LODImportSuccessful", "Mesh for LOD {0} imported successfully!"), FText::AsNumber(LODLevel));
					NotificationInfo.ExpireDuration = 5.0f;
					FSlateNotificationManager::Get().AddNotification(NotificationInfo);
				}
				else
				{
					// Import failed
					FNotificationInfo NotificationInfo(FText::GetEmpty());
					NotificationInfo.Text = FText::Format(LOCTEXT("LODImportFail", "Failed to import mesh for LOD {0}!"), FText::AsNumber( LODLevel ));
					NotificationInfo.ExpireDuration = 5.0f;
					FSlateNotificationManager::Get().AddNotification(NotificationInfo);
				}
			}

			// Cleanup
			for (int32 i = 0; i < LODNodeList.Num(); ++i)
			{
				delete LODNodeList[i];
			}
		}
		FFbxImporter->ReleaseScene();
	}
UAnimSequence * UEditorEngine::ImportFbxAnimation( USkeleton* Skeleton, UObject* Outer, UFbxAnimSequenceImportData* TemplateImportData, const TCHAR* InFilename, const TCHAR* AnimName, bool bImportMorphTracks )
{
	check(Skeleton);

	UAnimSequence * NewAnimation=NULL;

	UnFbx::FFbxImporter* FFbxImporter = UnFbx::FFbxImporter::GetInstance();

	const bool bPrevImportMorph = FFbxImporter->ImportOptions->bImportMorph;
	FFbxImporter->ImportOptions->bImportMorph = bImportMorphTracks;
	if ( !FFbxImporter->ImportFromFile( InFilename, FPaths::GetExtension( InFilename ) ) )
	{
		// Log the error message and fail the import.
		FFbxImporter->FlushToTokenizedErrorMessage(EMessageSeverity::Error);
	}
	else
	{
		// Log the import message and import the mesh.
		FFbxImporter->FlushToTokenizedErrorMessage(EMessageSeverity::Warning);

		const FString Filename( InFilename );

		// Get Mesh nodes array that bind to the skeleton system, then morph animation is imported.
		TArray<FbxNode*> FBXMeshNodeArray;
		FbxNode* SkeletonRoot = FFbxImporter->FindFBXMeshesByBone(Skeleton->GetReferenceSkeleton().GetBoneName(0), true, FBXMeshNodeArray);

		if (!SkeletonRoot)
		{
			FFbxImporter->AddTokenizedErrorMessage(FTokenizedMessage::Create(EMessageSeverity::Error, FText::Format(LOCTEXT("Error_CouldNotFindFbxTrack", "Mesh contains {0} bone as root but animation doesn't contain the root track.\nImport failed."), FText::FromName(Skeleton->GetReferenceSkeleton().GetBoneName(0)))), FFbxErrors::Animation_CouldNotFindRootTrack);

			FFbxImporter->ReleaseScene();
			return NULL;
		}

		// Check for blend shape curves that are not skinned.  Unskinned geometry can still contain morph curves
		if( bImportMorphTracks )
		{
			TArray<FbxNode*> MeshNodes;
			FFbxImporter->FillFbxMeshArray( FFbxImporter->Scene->GetRootNode(), MeshNodes, FFbxImporter );

			for( int32 NodeIndex = 0; NodeIndex < MeshNodes.Num(); ++NodeIndex )
			{
				// Its possible the nodes already exist so make sure they are only added once
				FBXMeshNodeArray.AddUnique( MeshNodes[NodeIndex] );
			}
		}

		TArray<FbxNode*> SortedLinks;
		FFbxImporter->RecursiveBuildSkeleton(SkeletonRoot, SortedLinks);

		if(SortedLinks.Num() == 0)
		{
			FFbxImporter->AddTokenizedErrorMessage(FTokenizedMessage::Create(EMessageSeverity::Warning, LOCTEXT("Error_CouldNotBuildValidSkeleton", "Could not create a valid skeleton from the import data that matches the given Skeletal Mesh.  Check the bone names of both the Skeletal Mesh for this AnimSet and the animation data you are trying to import.")), 
				FFbxErrors::Animation_CouldNotBuildSkeleton);
		}
		else
		{
			NewAnimation = FFbxImporter->ImportAnimations( Skeleton, Outer, SortedLinks, AnimName, TemplateImportData, FBXMeshNodeArray);

			if( NewAnimation )
			{
				// since to know full path, reimport will need to do same
				UFbxAnimSequenceImportData* ImportData = UFbxAnimSequenceImportData::GetImportDataForAnimSequence(NewAnimation, TemplateImportData);
				ImportData->Update(UFactory::CurrentFilename);
			}
		}
	}

	FFbxImporter->ImportOptions->bImportMorph = bPrevImportMorph;
	FFbxImporter->ReleaseScene();

	return NewAnimation;
}