I'm trying to develop Galaga in Processing, and I've made progress, but now I need to figure out how to register contact in the game, so that when the bullets hit the enemies they die, and when they touch the ship, the ship is destroyed. How do I do that? I have the files attached to this post. You'll need the Minim Library to run this. Any help is appreciated.
mediafire.com/file/0ot3rfzdob2jzxb/galaga.pde
