Would that not be able to be sorted by multiplying everything by 1000 or something? hence screen centre is still 0, but instead of using values of
-1 < x < 1 and decimals, you'd be using -1000 < x < 1000 and whole numbers (equivalent of a value to 3 decimal places). And of course round any calculations that would result in a decimal.
That said, I'm not a coder, this could just slow things down, and probably would interfere with some trig code or something at the same time... which wouldn't be good.
*shuts up now and leaves it for people who know what they're talking about*