Unfortunately most programs don’t have a builtin way of achieving this - need to do some geometry gymnastics. I had the same challenge in Grasshopper as well, I’ve attached my method built in Dynamo instead. It involves hyperextending the curves in an offset state and finding the most likely center segment when they’re all split at the intersections. It gets a bit messed up for very distorted shapes. You could also use trigonometry on each corner for a better but more complex outcome (I’m not going to do it, too complex/annoying!).
It uses one method from BiMorph nodes (Curves.IntersectAll).
find inner.dyn (73.2 KB)
