Function make_face_on 

pub fn make_face_on(
    model: &mut Model,
    surface: SurfaceId,
    wires: &[Shape],
    tol: Tolerances,
) -> OgeomResult<Built>

Build a face on a surface the model already holds.

The distinction from make_face matters more than it looks: a pcurve names the surface it is drawn on by id, so an edge’s pcurve and the face bounded by that edge have to name the same id. Registering the surface twice gives two ids for one surface, and every lookup of “the pcurve on this face” comes back empty even though the pcurve is right there.

Errors

As make_face.