Steve Baker (sbaker++at++link.com)
Wed, 1 Jul 1998 08:41:22 -0500 (CDT)
> I have the same problem on flight simulation,
Doesn't everyone? It's something that can be worked around
(with some measure of pain).
> The problem is that Preformer use only float not double.
Well, not even just Performer - OpenGL has the same problem - it
works in float precision.
Since an IEEE float has a 23 bit mantissa, you can only expect to
get precision down to about one part in 8 million or so - it's
quite a bit worse than that in practice due to accumulated
roundoff.
In the end, you have to resort to tricks like keeping the
eyepoint at the origin and moving the world past it.
It's not easy.
Steve Baker (817)619-8776 (Vox/Vox-Mail)
Raytheon Systems Inc. (817)619-4028 (Fax)
Work: SBaker++at++link.com http://www.hti.com
Home: SJBaker1++at++airmail.net http://web2.airmail.net/sjbaker1
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