||A pack that just gives back all the beasts in the world.
||A creature that lives in our simulated world.
||A full description of the state of a Beast.
||Manages a simulation group of beasts, handling their updating and providing
appropriate information to their pack finders.
||A Beast's mood, defined as two parameters: grooviness and intensity.
||Run a simulation of beast behaviour.
||Represents a direction in the xy plane.
||A dumb beast brain that just keeps on with the same direction and emotion.
||A dumb setup routine that just creates a couple of dumb beasts and a random
walker at random locations in random directions, with boring packs.
||A beast that takes a random walk around the screen, getting less intense the
older it gets and happier the further it is from whatever point it's at the
first time getMood is called (which is not necessarily its starting point,
but probably is).