How to make floor plan DXF from threejs model

I am currently trying to make my own program where I can load an IFC file into my threejs program. With the threejs model of the IFC, I want to be able to create 2d floor plans, that can be used as a drawing package, so dxf format.

I was wondering if anyone can point me to the best approach and method is. I already checked ifc.js and their code is outdated.

Hi Dieter - where does Rhino come in to this question?

-Pascal