open Jig;;
let (top, embd, [inf; outf]) = mix ([[1; 0; 3; 4]; [1; 2; 4; 3]],
    [|[|0.; 0.; -1.|]; [|0.2; 0.3; 0.26|]; [|0.; 0.; 1.|];  [|1.; 0.; 0.|]; [|0.; 1.; 0.|]|],
    [[2; 3; 4]; [0; 3; 4]]) (rp 5) in
let bl = Glue.morphgen (nz (embd, pyt)) top [] in
let th = 1. /. 3. in (jig embd bl inf outf).lray ([|th; th; th|], [|0.; 0.; -1.|])
(* Should yield approx ([|1/3; 1/3; -1/3|], [|0.; 0.; -1.|]) *);;