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# double precision

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Hi! Whats is different between double precision and float precision? Should such a feature (switching between this modes in realtime) implantated in a good engine? Thanks, Austrian Coder

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Good question. I''m wating for answer too.

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Good question. I''m waiting for answer too.

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if float (single precision) is fine, don''t go to double precision. gfx cards only handles single precision anyway.

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i think single precision floating points use 32 bits and doubles use 64 bits . . . i think, im sure someone will jump in and correct me if im wrong.

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float is 4 bytes and allows for -2.0E8 to 2.0E8 or something like that and a double is 10 bytes which obviously changes the percise the result is.

A float will round very easy. a double will round but have alot closer to real numbers that humans would figure if the as the number is spread behind the decimal.

a double double is something like 12 bytes. or something?

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a float or should I say IEEE float is
1 bit is sign
8 bits are the matanis
23 bits are the float point.

it works out to be something like
Sign matanis*float is the value....

and a 10 byte double has something like

1 bit is sign
26 bits are the matanis
53 bits are the float point.
same equation. If I remember the breakdown correctly

mantissa?

Brian

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the mantissa is the whole number part of the floating point number, i.e. 3.1459 . . .

the 3 is the mantissa and the rest is the floating point part.

once again, i think ...

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