- New Fish: Clown Triggerfish
- Update: Better overhead light
- Update: Closer bounds on fish movement
- Update: Mipmapping off by default
- Update: Fish take an interest more often
Big credit goes to cliff1066™ for his (Creative Commons Attribution licensed) clown triggerfish image, which worked quite well as source material. Check out his photostream for a bunch of cool stuff!
Closer bounds on fish movement is probably the most mysterious thing here. Basically, the fish periodically select a destination to swim to, and upon approaching that destination slow down, begin turning, and select a new destination. As they travel they'll occasionally re-evaluate and change to a new destination. The destination position itself is randomly selected within a range of X and Y, roughly encompassing the background area.
As I've noticed occasional comments about fish leaving and not coming back (which is impossible given the way the system works, they simply cannot try to go anywhere outside the specified X and Y bounds), I'm guessing this just means the fact that they'll sometimes leave the visible area before turning and swimming back. To that end I pulled in the left and right edges of their range by about 10%, so they shouldn't leave the edge of the visible area as much.