BBTK_INPUT(VolumeRenderer,OpacityFunction,"Opacity function",vtkPiecewiseFunction*,"");
BBTK_INPUT(VolumeRenderer,In,"Input Image",vtkImageData *,"");
BBTK_OUTPUT(VolumeRenderer,Out,"3D object to plug into a 3D viewer",vtkProp3D*,"");
BBTK_INPUT(VolumeRenderer,OpacityFunction,"Opacity function",vtkPiecewiseFunction*,"");
BBTK_INPUT(VolumeRenderer,In,"Input Image",vtkImageData *,"");
BBTK_OUTPUT(VolumeRenderer,Out,"3D object to plug into a 3D viewer",vtkProp3D*,"");