Here are my initial attempts. I intend to use a closed curve, so I began with that as a default setup. Using a flat base plane along with the extrusions gives the intended result in Rhino. Loft did not work for me in GH (I was probably doing something wrong that it did not create a closed loft for me), so I went on to trying a sweep1 command. With a flat base plane, the GH result is nearly perfect to Rhino’s (attempt 1).
Trying attempt 2 with a slightly curved, extruded base plane seemed to give close results, so I went on to attempt 3 with a doubly-curved base plane and a third radii point. Here I found that the GH sweep1 result does not follow the base surfaces at all (the big plane or the cylindrical/ elliptical extrusions). The resulting GH sweep1 cannot cut the base surfaces because it does not hit them properly. When I saw this, I looked back closer at attempt 2 and found the same thing, that the sweep1 does not cling to the base surfaces (logically, now that I look at it). However, in attempt 3, the sweep1 result at least made a surface. Rhino’s FilletEdge variable command failed to build the surface.
I’m out of the office so I won’t be able to try again till after this week.
VariableFillet01z.3dm (703.0 KB) VariableFillet01z.gh (27.6 KB)