Filleting Curves in 2D and 3D

Hi,

Pretty basic question.

Why is my script not filleting the two curves that I have selected in my rectangle? (The bottom script)

I am trying to smooth the edges on the massing that I have, a process that I am trying to learn via a tutorial on youtube.com (The top script). I figure that the top of the massing needs to have filleted edges though which is why I am practicing in two 2D before I try to get the list items required to do it on my massing. To get that massing, I just extruded some curves I created in Rhino.

Essentially, I want the building be smooth like the image provided. If you have any suggestions on how to do this more efficiently, I would love to know.

Thanks in advance.

Massing Curves.gh (11.5 KB)

I think this is what you try to achieve. Massing Curves_ME.gh (21.1 KB)
If you don’t fillet the polyline before extruding; the corners of the mass will be filleted.

Yes, that is what I am trying to do. Thank you!