a = Cube
b = Cube
c = Cube
draw a
draw b behind a
draw c above b
save as "step.inv"
class Step = "step.inv"
d = Step
// Note that d will be down 1 unit from a.  This is normal since the
// new object, d, has a center at 0,0,0; the old object is centered at
// 0,1,0
draw d to the left of a