Function pbrt::shapes::nurbs::nurbs_evaluate_surface

pub fn nurbs_evaluate_surface(
    u_order: i32, 
    u_knot: &Vec<Float>, 
    ucp: i32, 
    u: Float, 
    v_order: i32, 
    v_knot: &Vec<Float>, 
    vcp: i32, 
    v: Float, 
    cp: &Vec<Homogeneous3>, 
    dpdu_opt: Option<&mut Vector3f>, 
    dpdv_opt: Option<&mut Vector3f>
) -> Point3f