Function intersect_prism

pub fn intersect_prism<M: TriangleMeshView + ?Sized>(
    mesh: &M,
    plane: Plane,
    region: &[Polygon],
    tolerance: Tolerance,
) -> Result<Projection, ProjectionError>

Intersect a mesh footprint with a vertical prism over a 2D region.

The prism is infinite along the plane normal, so this is exactly the planar intersection of the mesh footprint with region. Naming it separately keeps the caller from having to know that identity, and leaves room for a bounded prism later without changing the call site.