    source = vtkHyperTreeGridSource()
    source.SetMaximumLevel(6)
    source.SetDimensions(4, 4, 3)  # GridCell 3, 3, 2
    source.SetGridScale(1.5, 1.0, 0.7)
    source.SetBranchFactor(4)
    source.SetDescriptor(descriptor)
