The only problem with this is, does anyone have any (hopefully fairly fast) fixed point routines for ln and exp?

Talk to the Fractint guys. They're experts at doing floating-point operations with integer math. Incidentally, when one of the Empeg guys complained that the Vorbis format required floating-point to get its job done, that was the first thing I thought of. If you're willing to have a limit to the number of decimal points in your precision, you can do a lot of very fast floating-point math with integer operations. (Don't ask me how, though, it's all greek to me, ask the Fractint guys.)

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Tony Fabris