Anisotropic Reflections Instead of Highlight

I’m sure I’m just being stupid and missing the control to do this, but can vray do anisotropic reflections, or only anisotropic highlights? And if it can do aniso ref, how do I turn it on?

- Neil

Yea u sure can, if u open up the BRDF drop down there u can control rotation and the anisitropy. No need to turn it on

I tried that before and it doesn’t seem to do anything. Here’s my steps…

1) Make an object to reflect
2) make a ground plane
3) Assign VrayMtl to groundplane, set reflectivity to a high value
4) render, I get the object’s reflection
5) Change anisotropy from 0 to 1
6) render, still no change to the reflection.

- Neil

You have to turn refl. glossies to at least 0,98 I think in order for the anisotropic to do anything. At least in my experience.

Yes forgot to mention it is only noticeable when u have some highlights, so u could unlock highlights and set it’s to something around .8 or something pleasing and then u could see the rotation happening

Nope, I turn glossiness to 0.9, I get a blurred reflection, but then changing anisotropy from 0 to 1 doesn’t change the reflection at all.

- Neil

Turn GLossines to 0.75.
Anistropic to 0.75 and render it then. 1 does not work.

Yes if am not mistaken 1 won’t work try smaller increments like .2 or .5

And add some rotation also

I would suggest mapping out proper rotation coorditantes using uvw…

Thanks DADAL, that was the issue, I was always using a value of 1, so I was never getting any blur. is this a known bug? Should I report it? Certainly wasted a chunk of my day.

- Neil

Technically it should be achieved with bump mapping or high frequency displacement so I’m not sure if it’s a bug or a fall back of “faking” the effect.

I reported it as a bug, at the least the values should be clamped to avoid 1 or -1 so we always get some sort of effect.

Thanks everyone for the help.

- Neil

The Anistropic effect is just a SIMULATION. In real world you would need to use displacement and not have to use anistropic effect. Or bump+ slight anistropic effect as far as I know.

Value of 1 its known and normal to not display anything. I think it goes down to maths…

Oh I know the way it works in real life (wrote a tutorial about it a long time ago: http://www.neilblevins.com/cg\_education/aniso\_ref/aniso\_ref.htm), and I’ve used bump before to simulate it, but sometimes you just need the fast close enough method :slight_smile: If the math breaks at 1, that’s fine, I’ve requested the value gets clamped before 1 so the material is more intuitive to new users.

- Neil

I like it!:+1:

Haha you just repeated exactly what I said!

(I missed your tutorial on the topic Neil, my bad)

It’s all good. I’m updating my tutorials on metals right now with vray info, which is why I’m asking all these questions.

- Neil

I remember looking at some of these old tutorials and closing them because I was too stupid to understand any of it haha.
You had knowledge and wisdom back then that 99.99% of artists still don’t have, myself included…
Literally years ahead of their time.

Well thanks Grant, although I do try my best to make my tutorials understandable by anybody, I don’t want them to be advanced only :slight_smile: We’re all just spreading the knowledge around, you guys know more about vray than I do, so I’m asking questions. And I probably know a few things you don’t, and I’m trying to spread that through my website, between all of us we’ll keep pushing this art form forward as a big world wide team.

- Neil