Jim, I mentioned that I have a 32" HD monitor that runs 24/7/365. The only time it gets turned off is in a power failure. After a week or so of running, I notice fewer and fewer fish. Well tonight I went looking for them. I scrolled all the way to the right. Nothing. Then I scrolled all the way to the left, and lo and behold, there they were, just circling and circling. What do you make of that? See:
http://youtu.be/pPstmIImmYY
Mike
Very entertaining, and an example of what is often referred to as "rounding error" or "precision failure".
It's a bug. Jim will have to sort out where it occurs and find a fix.
Not uncommon in financial software - and results in calculations that are "off by one cent". In this case, my guess is that the "problem" is that the horizontal position in the tank is not
exactly representable in 32 bits (or whatever precision is being used). Over time, and millions of calculations, some error accumulates.
That's the general idea. I'm confident that Jim can easily fix the bug.