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Dtox
01-29-2008, 02:09 AM
2 part question.
More for confirmation of the issues.

1) Is oren-nayar the same as lambert? If you set the roughness to 0?


2) If I were rendering with an HDR image, is it safe or advisable to use pure reflections only? Instead of specular?

A scenario I'm unsure of is that I'm creating a brick wall shader using the oren-nayar shading model.
So if I have a low reflection setting with a high dispersion value, will this be more scientifically correct?
Or is specular the way to go disregarding scientific accuracy for the best appearance?

Any information anyone has will be good. Whether it's fact, theory or opinion.

Carry on.
AdamT
01-29-2008, 04:35 AM
1) Oren-Nayer at 0 is the same as Blinn ... which may or may not be the same as Lambert?

2) Specular is nothing more than fake reflection of lights, since most CG light sources do not appear in raytraced reflections. Whether you want/need them really depends on your scene. If you're relying entirely on HDRI for lighting, there's no need. If you're only using HDRI for reflections, and your lights don't match up with the HDRI's lighting, you might want them.
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01-29-2008, 04:35 AM
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