Projecting lines on curvy sufaces

Is it possible to project a line on a surface (made with toposhaper)? What I would like to accomplish is to project the lines, which are now under the surface, and hence non-visible on the surface. The straight lines show the the lot boundaries.

Untitled.skp (1021.7 KB)

You could make a temp group where you extrude the edges to cross the surface you want to “project” onto. Then use entities.intersect_with

@tt_su, thanks for the suggestion! How would you do it? I tried the extension “Extrusion Tools” / Extrude Edges by Vector to Object. What happens is that the extrusion stops at the group that contains the surface, even if the object is hidden.

Just to report, the Sandbox/Drape tool takes care of this pretty well. Result:

Are you looking to write an extension that does this? Or to find an existing extension?