Ah ok, gotcha. Well cool.
So I know Quigibo just said there will be a way to do it in the near future but this sort of does the affect you want. I don't know if it is usable in your circumstance at all though. But who knows. Just thought I'd give it a shot.
.BLUE
ClrDraw
[FF818181818181FF
0000000000000000→Pic1
For(A,0,8
Pt-On(0,0,Pic1
Pt-Off(0,A,Pic1+8
DispGraph
Pause 100
End
Again, not sure if you can use it (or if you even want to give that there will be a way to do it soon). This probably also isn't a very good way to do it.