View Full Version : SubD Surface Problems...

08 August 2004, 11:46 PM
What is going on here and how can I go about fixing it?
I am using a chrome texture I am working on I can post a picture of the inputs and outputs if it will help. The shader is a anisitropic

Its modeled in polys and converted to subds im using maya 5.0.
If I assign a lambert to it there are no problems.

08 August 2004, 12:17 AM
I think you may have your ramps reversed for one thing, as for fresnel fake it should be getting more reflective as the camera eye approaches a 180 degree angle, as you have it it looks very specular and very reflective at the 90 degree angles.

Have you tried using something other than an anisotropic base material like a blinn or phong?

08 August 2004, 10:14 AM
Yeah, I think anisotropy only works well with NURBS, something to do with the uv's...

Staffan Norling
08 August 2004, 10:40 AM
Yeah, it looks like a problem with the UVs.
The highligts of an anisotropic material are stretched in tangent-space, and the uv-coordinates are used to define it. Make sure you have nicely laid out uv-shells, all aligned in the right direction. Beware of UV-borders. The tangent and the binormal (two of the axis in a tangent space coordinate system) are interpolated, just like the normals of a smooth surface. If you have borders in your uv-map, the tangent and binormal won't be interpolated over them, and it could result in ugly specular borders (like you have now).

08 August 2004, 02:59 PM
yes bill I have tried using a phong and it still happened.
Ive went ahead and went back to an older file grabbed a poly version and just poly smoothed it and suprise now its fine.

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