Hopefully self explanatory GIF:
The middle surface that gets left hanging in the air is an edge surface built with the help of the two blend curves, all with history enabled.
Seems Rhino’s history is really quite poor, unfortunately. This slows down the otherwise excellent surface sketch capabilities of Rhino.
extendsrf.3dm (79.0 KB)
Bonus horrible history behavior:
I deleted the blend curves and instead matched each surface edge of the network surface using curvature and the target iso direction, and then tried to line up the edges nicely with an extend surface in the other direction…
Got that, thanks - RH-59212 BlendCrv: History update problem
-Pascal
