Snow 3.0 with collision

Hey all. So I used a variation of the Snow tutorial for a site and it works great aside from one thing. The snow (or leaves, in my case) tend to disappear at the edges of the movie clip instead of bouncing off or simply avoiding the area.

Anyone have an idea on how to add some simple collision detection for the movie clip’s walls? Still kind of sucky at AS so I can’t figure it out on my own. :slight_smile: