Hair shader Anisotropic problem
Hi everyone.
I'm trying to recreate this type of material.
https://www.artstation.com/artwork/LR3qqR
but i have some problems with the anisotropic part.
why does it generate those artifacts of light for me? (red circles)
how can I make the anisotropic part look like the one in the link?
mine is not very evident (green circle)
how can i solve?
the mesh is smoothed and the uv seams are all facing inwards (towards the head).
Thank you
Replies
Anisotropy often uses tangent and bitangent data, which is derived from the UVs and the vertex normals.
So take a close look at UVs, make sure they are welded and contiguous, with minimal stretching.
Also the normal map.
Make sure it has correct gamma (linear) and correct value ranges.
Incorrect gamma will cause these kinds of errors. The thumbnail for the normal map looks way too bright.
If you look at a histogram, the red and green channels should be 128-255, and blue should be very bright.
It looks like the textures are coming from a Texture Project, so the color space for the normal map will be configured automatically. The preview thumbnail will look brighter when set to linear space (the correct setting).
Please make sure that your mesh normals are averaged/smoothed, and that your exporter is configured to write the normals. As Eric mentions, making sure the UVs are welded is a good idea too. If this doesn't solve it, can you test with GGX reflections and verify whether you're seeing the same faceting artifacts?
Could you also confirm whether these artifacts are visible with ray training on, off, or both?
Fixed artifacts.
When I exported from Zbrush I didn't have the smooth normals option turned on.