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RandyU
05-26-2001, 09:14 PM
This is not an OpenGL question.
I have -NAN (not-a-number) as a normal vector. So my normals are pretty random.
I'll try to use spheremap before fixing - it may be looking cool.
I cant find a documentation on NAN.
Which operations can have a NAN as results?
May it be crossproduct on invalid triangle?
How NAN is represented? 0xFFC00000, or there are other numbers?

Thanks in advance for any help.
***
Nevermind, I've already fixed it.
There was smth with wrong indexing.
BTW spheremap with invalid normals looked pretty dull.

[This message has been edited by RandyU (edited 05-26-2001).]

Gavin
05-29-2001, 01:34 AM
Weel just to answer anyways... a couple of NAN producers are trig functions errors i.e.
inv sin(x) -> -1>x>1
or division by zero.....

gav

RandyU
05-29-2001, 04:09 AM
1/100000000 also produces NAN.
AFAIK it's called "denormalized result"