Planar Anisotropy Issue

[möbius]

Hey everybody,

I would like to talk about anisotropic reflections again, the planar ones. I made a setup with a circular plane, assigned a diffuse metal with Anisotropic reflections to it (VrayMtl, Spiral Gradient in the Aniso rotation and so on). The thing is it looks good in a still image but it behaves wrong when the object is animated.

See the Video:

https://drive.google.com/open?id=0B6...FZjd2s1Vm1hQXM

When the object spins around it's local axis the reflection spins as well and this shouldn't be the case in my opinion. Is there anything i'm doing wrong here?

Here is also the Max-File:
Anisotropy_Issue.zip

[vlado]

If the surface of the cylinder is perfectly perpendicular to its local Z axis then this is normal. In that case either base the anisotropy on some mapping channel, or move slightly the center vertex in the local object Z direction.

Best regards,
Vlado

[möbius]

Hi Vlado,

thanks for the hint, but unfortunetelly this soltion will only work for the cylinder which is merely a test object. The final geometries the Shader is for are mainly CAD-Objects like the gear surrounding the cylinder in my sample szene. So, no mesh manipulation possible in this one.
I also tried some facy stuff like rendering the normals of a cone from the top like this...



... and using it in as normal map in the bump slot hoping it will give me a similar result like pushing the middle vertex, but the result wasn't that great either.

Is there really now other way to direct the reflections from the center out with no particular angle?

Otherwise I put it on the whish list

Regards,
Markus

[vlado]

Hm, it might be relatively easy to do... I have an idea, but I don't know if it will work for you. Are you willing to test a V-Ray build to see if it works better for your case?

Best regards,
Vlado

[möbius]

Yes, Of Course!

[Art48]

If the surface of the cylinder is perfectly perpendicular to its local Z axis then this is normal

Can you elaborate on that? What does "normal" mean in that context? Expected behaviour? If so can you explain what physical background that would have? At the moment I can't imagine a way for that to be normal or realistic.

[möbius]

Hm, it might be relatively easy to do... I have an idea, but I don't know if it will work for you. Are you willing to test a V-Ray build to see if it works better for your case?

Best regards,
Vlado

Just out of curiosity, what is your idea or why are you not sure if it works in my case?

Markus

[möbius]

Any news here?

[Art48]

Also would still like to know the physical background