There’s a small papercut that took me quite long to figure out:
for since for 99% of the cases Rhino.Geometry.Intersect.Intersection returns points in the same order as the line you cut with (from start to end). And in some cases they don’t.
I’m not sure f this was the intended behavior, and the solution for it this problem is trivial, but figuring out the behavior was not. A small note in the documentation that the point order can be random could be an improvement.
Attached is a grasshopper file to reproduce this behavior
MeshLineBug.gh (1.9 MB)