fft – 3d-mesh roughness frequency histogram

I want to compare surface features (especially roughness) of different 3d scanned meshes.

Are there any good ways to generate a histogram of the spatial frequencies in the surface of a 3d mesh?

Other similar measures to compare “roughness” for watertight 3d shapes would also be greatly appreciated.

I found CloudCompare to generate roughness histograms (based on the distance of each point to the average plane of points in a neighborhood radius. The histogram shows how often this distance value is found for the pointcloud).

I am not too happy with this because choosing a neighborhood radius seems quite arbitrary (and a specific choice would be hard to justify). Also it seems to me to contain little information about frequencies (e.g. how highly rough areas overlap with lower frequency large scale “roughness”). Every point only gets one value in the histogram although it is part of several overlapping spatial frequencies in the surface.