Does it makes sense to have sphere and non-sphere versions of
nonbonded lists (ones with and without non-zero radii)? I know there
are contexts where you can get away with the latter, but it seems like
we mostly want spheres and the added confusion and maintenance burden
might overwhelm the advantage. Thoughts? I don't see myself using the
non-sphere version.
If the radii are zero, the difference comes down to fetching a zero
attribute and adding it to each radius. And making sure that each
particle has such an attribute.