// getRenderer().AddActor(axis);
}
public void addTube(vtkPoints points, vtkUnsignedCharArray colorArray, vtkFloatArray radiusArray, double opacity) {
vtkCellArray cellArray = new vtkCellArray();
cellArray.InsertNextCell(points.GetNumberOfPoints());
for (int j = 0; j < points.GetNumberOfPoints(); j++) {
cellArray.InsertCellPoint(j);
}
vtkPolyData polyData = new vtkPolyData();