// volume property 
			int shade = 0, compos = 0, interp = 0;

			// renderer 
			vtkRenderer ^ren1 = gcnew vtkRenderer();
			ren1->SetBackground(1.0, 1.0, 1.0);

			// render window 
			vtkRenderWindow ^renWin = gcnew vtkRenderWindow();
			renWin->AddRenderer(ren1);
			renWin->SetSize(800, 600);

			// interactor 
			vtkRenderWindowInteractor ^iren1 = gcnew vtkRenderWindowInteractor();
			iren1->SetRenderWindow(renWin);

			// set up the input file for unstructured grid reader 
			//1.Create a volume data 
			// create sphere geometry 
			vtkSphereSource ^sphere = gcnew vtkSphereSource();
			sphere->SetRadius(1.0);
			sphere->SetThetaResolution(18);
			sphere->SetPhiResolution(18);
			//2.Apply the tetrahedral mish 
			vtkPolyData ^vp = gcnew vtkPolyData();

			vtkDelaunay3D ^unstructuredReader = gcnew vtkDelaunay3D();
			unstructuredReader->SetInput(sphere->GetOutput());


			// set up opacity transfer function 
			vtkPiecewiseFunction ^opacityTransferFunction = gcnew vtkPiecewiseFunction();
			opacityTransferFunction->AddPoint(0, 0.02);
			opacityTransferFunction->AddPoint(4095.0, 1.0);

			// set up color transfer function 
			vtkColorTransferFunction ^colorTransferFunction = gcnew vtkColorTransferFunction();
			colorTransferFunction->AddRGBPoint(0.0, 0.1, 0.1, 0.1);
			colorTransferFunction->AddRGBPoint(4095.0, 1.0, 0.0, 1.0);

			// set up volume property 
			vtkVolumeProperty ^volumeProperty = gcnew vtkVolumeProperty();
			volumeProperty->SetColor(colorTransferFunction);
			volumeProperty->SetScalarOpacity(opacityTransferFunction);
			volumeProperty->SetInterpolationType(interp);
			volumeProperty->SetShade(shade);
			// Add scaler value 
			vtkDoubleArray ^arr = gcnew vtkDoubleArray();
			arr->SetNumberOfTuples(unstructuredReader->GetOutput()->GetNumberOfPoints());
			arr->FillComponent(0, 1.0); // e.g. double value = 1.0;
			arr->SetName("myarray");
			// MessageBox.Show(arr.GetData( 
			//unstructuredReader.GetOutput().GetPointData().SetScalars(); 
			unstructuredReader->GetOutput()->GetPointData()->AddArray(arr);
			unstructuredReader->GetOutput()->GetPointData()->SetActiveScalars("myarray");


			// composite function for strucured grid renderer 
			vtkVolumeRayCastCompositeFunction ^compositeFunction = gcnew vtkVolumeRayCastCompositeFunction();
			compositeFunction->SetCompositeMethod(compos);

			//unstructuredGridRendering 
			vtkUnstructuredGridVolumeRayCastMapper ^volumeUnstructedMapper = gcnew vtkUnstructuredGridVolumeRayCastMapper();
			//vtkVolumeRayCastMapper volumeUnstructedMapper = new vtk.vtkVolumeRayCastMapper(); 
			//volumeUnstructedMapper.set  (compositeFunction); 
			volumeUnstructedMapper->SetInput(unstructuredReader->GetOutput());

			volumeUnstructedMapper->SetScalarModeToUseCellData();

			vtkVolume ^volume = gcnew vtkVolume();

			volume->SetMapper(volumeUnstructedMapper);

			volume->SetProperty(volumeProperty);

			// add volume to renderer 
			ren1->AddVolume(volume);

			renWin->Render();

			iren1->Start();