-4.5 5 setxrange
-3 3 setyrange
20 setxunit
6 6 7 SetCamPos
0 0 0 SetCamView
qplanxy
2 setlinejoin 

.1 setlinewidth
.6 setgray

[-1 0 -1 2 2 2 3 0] 2 [3] newruban
dup (jaune) (cyan) inoutputcolors
dup drawsolid**
noir
dup [0 1 3 {} for] solidshowsommets
[0 1 3 {} for] solidnumsommets