make regular triangle BUG: first try doesn't work please bang twice or method "precision" for setting the size of the output grid. in which the peak represents the amount of similarity between the two polygons, and the position of the peak represents the optimal rotation for maximum overlapping of the polygons. The rotation origin is assumed to be the centroid (#moment 1) NOTE: requires [#fft] translations, e.g. [# +] rotations, e.g. [#rotate] a 2-D polygon as N by 2 grid a 2-D polygon as N by 2 grid Comparisons are meant to be invariant to the following transformations: scalar scalings, e.g. [# *] with only one value. a float grid of size 256 showing the cross-correlation between polygons in polar form relative to their centroid.