pst-rubans – Draw three-di­men­sional rib­bons

The pack­age uses PStricks and pst-solides3d to draw three di­men­sional rib­bons on a cylin­der, torus, sphere, cone or paraboloid. The width of the rib­bon, the num­ber of turns, the colour of the outer and the in­ner sur­face of the rib­bon may be set. In the case of cir­cu­lar and con­i­cal he­lices, one may also choose the num­ber of rib­bons.