GGX Shading Model For Metallic Reflections

[soulburn3d]

Here's an article I wrote testing out the new GGX shader in the latest vray. If you have any suggestions or see parts that don';t make sense, feel free to give me a poke...

http://www.neilblevins.com/cg_education/ggx/ggx.htm



- Neil

[Deflaminis]

I think it's a great article. The longer reflection path on the bottom images are great to see the ward vs. ggx and it also shows up on the chamfers quite a bit too it seems. Nice work and thanks for sharing.

[soulburn3d]

Thanks for the feedback. I was doing these tests to help decide if I should switch over and decided the results were pretty enough to share

- Neil

[vlado]

Nice article, Neil! Thanks for sharing.

Best regards,
Vlado

[Vizioen]

Always like reading your articles Neil, easy enough for me to understand them and makes me feel smarter every time .

[dgsantana]

Great article Neil, and a nice reference for GGX values

[soulburn3d]

Nice article, Neil! Thanks for sharing.

Thanks for getting the feature in there Vlado, I think it'll make a lot of people happy.

Always like reading your articles Neil, easy enough for me to understand them and makes me feel smarter every time .

I try my best to go for "approaching complex topics in as simple a way as possible", so glad I succeeded.

Great article Neil, and a nice reference for GGX values

Thanks, that was a late addition to the article, after I was done I found myself wanting a diagram like that, so I quickly threw one together and then added it.

- Neil

[bardo]

Always like reading your articles Neil, easy enough for me to understand them and makes me feel smarter every time .

The same feeling for me... ahahah

Thanks Neil

[MoonDoggie]

Neil, thanks for the writeup. Just a quick question, on the gloss 1.0 tail 1.0, why is the tail reflection in slightly a different orientation?

[R2J2]

Great write up Neil,
the Disney example is interesting, the real chrome they capture has a distinct yellow rim to it and blue falloff. I wonder if that could be reproduced with a coloured light and white balance.

[Vizioen]

Isn't that a camera thing?

[soulburn3d]

Neil, thanks for the writeup. Just a quick question, on the gloss 1.0 tail 1.0, why is the tail reflection in slightly a different orientation?

Actually, those are the reflections of the spheres beside it, not part of the specular reflection of the light

Great write up Neil,
the Disney example is interesting, the real chrome they capture has a distinct yellow rim to it and blue falloff. I wonder if that could be reproduced with a coloured light and white balance.

Ya, I saw that too. I would assume they would have done whatever they needed to to properly balance the light to remove color shifts. Or perhaps real chrome does something interesting to a white light's color wavelengths. If I ever find a good scientific explanation I'll do another tutorial on it.

- Neil