The paper shows how to implement the generalized Harvey-Shack (GHS) method for isotropic rough surfaces discretized in a polar coordinate system and approximated using Fourier series. This is particularly relevant for the use of the GHS method as a boundary condition for radiative transfer problems in slab geometries, where the discrete ordinates method can be applied to solve the problem. Furthermore, such an implementation is a more convenient discretization of the problem than the traditional direction cosine space that has its strengths in analytical problems and intuitive understanding (mainly due to its translation invariance). A computer implementation of scattering from a Gaussian rough surface with Gaussian autocovariance written in Python is included at the end of the paper.