I realize this is experimental code so please don't think I'm complaining. I call a drawSphere routine a lot in my own codes that I'm porting to plugins. I called this routine instead to see how it works and have a few observations. The first is that the fill value for the sphere cannot be specified, I suspect this is just for the experimental stage. The second is that a few spheres I tested were not quite spheres, radius = 1.8 draws an example peculiar shape. I also suspect the spheres are slightly too large (maybe filled at distances <= R rather than just <R). This is based on restoring thresholded exact Euclidean maps (Danielsson's algorithm) and I obtain a larger volume than my original. Maybe adding an option for <R and <=R wolde be useful. I hope this is helpful.
Kind Regards
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