In either case, if you have a second to think you should try and shoot the UFO before it fires another missile. Alive is based on an Asteroids Java applet written by Mike Hall . See the License Agreement on Mike Hall's Asteroids Page for further information. The orignal applet is running there, and you can dowload Mike Hall's source and executable from here as well. You can view or download the Asteroids Alive code from Rucker's Asteroids Alive Page .
Asteroids avoid the bullets now.
The algorithm involves flying away from the closest bullet, if any, whose distance from you is presently decreasing. Bullets more than half a screen away are ignored. The mass of these flat asteroids is thought of as proportional to the cube of their radius. Round or a square world, with bounce and wrap. Godmode in which you're invulnerable.