Creating the same model using Divide Surface, Isotrim etc

Hi,

This is my second post here after the help I got for the entrance about the model that I am trying to do. Since I am new to grasshopper I am kinda struggling to understand how to use certain commands.

I was wondering if I could possibly redo this model where I generate a surface with the roof curves and use commands such as Divide Surface and Isotrim? I have to redo it with this method but I can’t get the same result as the one I have made before.

The grasshopper file of the old model:
Mediopadana_re.gh (21.1 KB)

I would appreciate it if someone could explain how it works! Thank you for the help!