I'm fairly new to WebGL and have a Problem.

I wanna draw mutliple Objects, I know how to do that and it's working when I draw them all at the same time.

Now I wanna draw this objects one after another, if one object hits the ground another one should drop from the top.

I know how to do that but the object which was on the ground always disappears.

How can I solve this, that the object on the bottoms stays there?