Re: FW: Re: [ATM] re:Arbitrary ray origins

["Richard F.L.R. Snashall" <rflrs@rcn.com>]

mlbrown@everstrive.com wrote:

> T = gI + [g(-N dot I) - sqrt( 1 + g²((N dot I)²-1))] N

The domain interrogation I mentioned is:

        N dot I < 0

If true, the ray hits the surface in the wrong direction
to be refracted.  This actually happens in some fisheye
designs.  However, it also means that the user has to
have some way of defining which way is "out".

-- 

Rick S.

http://users.rcn.com/rflrs

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