Obtaining a vtkPolyData after running vtkWarpScalar

I used a vtkWarpScalar filter to obtain the elevations from a triangulated surface. Now, I need to be able to access (or convert?) the mesh generated Into a vtkPolyData. Does anyone know how to do this?

vtkWarpScalar() inherits from vtkPointSetAlgorithm() that has a function called GetPolyDataOutput()