Question

I just want to animate snowflakes/other objects in the background falling down. I know a couple of ways to do this, but am really looking for the most efficient solution. I could use this doing a UIView block animation. I would have it start at the top of the screen and animate to the bottom of the screen over a period of time, then on completion start it again at the top. Is that a good way to do it? I’m looking for efficiency here.

Answer 1

You want a CAEmitterLayer!
http://developer.apple.com/library/mac/#documentation/GraphicsImaging/Reference/CAEmitterLayer_class/Reference/Reference.html

It’s iOS 5 only though.

http://developer.apple.com/library/mac/#documentation/GraphicsImaging/Reference/CAEmitterLayer_class/Reference/Reference.html