This is an example of "no screen refresh" to make a 3D object. The direction variable allows you to specify the direction. The sprite will forever clear, set its x/y to 0, and then stamp/change y/change costume to render an object.
I have seen cloning 3D and other things, and I want people to know how easy no screen refresh is! I don't know if it will work with less lag in some situations, but it still might work. And I was thinking that I might try to make something like MrLog's 3D platformer with it. http://scratch.mit.edu/projects/2622151/