photonstorm/phaser-examples — pull request #35 by Bjvanminnen (2014-04-23 05:22:57+00:00)
Title: out of bounds bullets don't die

Without checking world bounds, out of bounds bullets don't die. As a result, once you've missed with each of your thirty bullets, you stop firing. Same thing happens with enemy - once they've missed 30 times, they stop firing.