From: Ebert Maximilian (m.ebert_at_umontreal.ca)
Date: Wed Oct 07 2015 - 11:35:27 CDT

I will answer my own question. I looked through the source code of VMD and cone has an undocumented option “radius2”. Maybe you should add this to:

http://www.ks.uiuc.edu/Research/vmd/vmd-1.9.2/ug/node129.html

so the command I was looking for was:

draw cone {2 0 0} {3 0 0} radius 0.3 radius2 0.1

Greetings,

Max