Cut PolyLine Frame using Surface

So i created frames of polyline that i wish to cut it with a surface. How can i do that in GH?

image (18.8 KB)

Use split with brep

can u show me? I tried and it didnt work.

I am hoping the polylines cut diagonally at the points position. So, i will have left diagonal segments and right separate

If you want like this you need to use Pufferfish Point surface side (26.6 KB)