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0 pointsrwallace9y ago0 comments

To clarify, any time I in any way praise floating point, I'm always talking about double precision. I think single precision floating point should never have been invented, and given that it unfortunately was, it's best to behave as though it doesn't exist. Don't get me started about half precision.

Financial calculations are another matter; they usually require decimal arithmetic, not because it doesn't give rounding errors, but because it gives the same rounding errors an accountant gets when he checks the result with his desk calculator, and that's the requirement.

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MaulingMonkey9y ago

> To clarify, any time I in any way praise floating point, I'm always talking about double precision.

64-bit fixed point solves a lot of problems too :)

> I think single precision floating point should never have been invented, and given that it unfortunately was, it's best to behave as though it doesn't exist. Don't get me started about half precision.

A 4x memory bandwidth & storage penalty for HDR buffers would be absolute murder (bloating a single 4k RGBA surface to 265MB if I've done my math right), so I'm glad we have the option. And in the historical context lower precision options were invented in, RAM wasn't nearly as cheap as it is today. Tradeoffs.

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