Function divide_by_continuity 

pub fn divide_by_continuity(
    model: &mut Model,
    shape: &Shape,
    at_least: Continuity,
    tol: Tolerances,
) -> OgeomResult<Built>

Cut every edge and face of shape where its spline is less smooth than at_least, so each piece is at least that smooth throughout. A knot is judged by its multiplicity, so G1 and G2 ask what C1 and C2 ask.

Edges are cut at their curves’ knots; faces along their surfaces’ knot lines, for a spline, an extrusion or revolution of a spline, and a trimmed or offset surface over one.

Errors

As divide_face, for a cut that cannot be made.