hair shader issue


I was working on a charater but during the hair shading process i noticed that when you look at the hair from the light it looks good, but when you look at it with the light behind the hair it “glows”.

Could you please help me solve this? I tried working with the “default lit” shader and while the other characters still look good, this one needs the “hair” one.

I will provide you with three images: two showing the model and one the material setup.

Waiting for your answer,

Matteo Dell’Acqua

Today I also tried playing with “roughness”, “scatter” and “backlit” but to no avail. What do you suggest trying?

Apparently this is a bug with UE4 at the moment and is supposed to be fixed in 4.16 or 4.15 if they get time. Im having the same issue currently.

Did you try to remove the normal map from the tangent slot?
I don’t think you should use a normal map with this shading model.
You need to bake it in the shift-texture, which defines how the light is shifted on each hair strand. Also check the actual hair shader implementation on the “content examples” demo.

Yes, i tried removing it, but it looked better with it on and it didn’t resolve the problem

solved here: DFAO with characters - Rendering - Epic Developer Community Forums

Thanks for the answer but even disabling Temporal AA the issue remains.

I think he meant the change in the shader file, not disabling AA.

Sorry for the ignorance, but how can i bake a tangent map from a normal?

Thank you very much, I’ve tried with the shader file and now everything work great. thank you again

Dunno if you mean a flow- or a shifttexture by “tangent map”.
For shifttextures, I bake height/displacement maps and adapt this texture afterwards to my needs in photoshop.
I’m not sure how to bake a flowmap, but it’s not necessary, as long as your hairtexture is pointing in one direction, up/down for example.

Sorry, found a solution: use the transform vector from tangent to local

thank you for your time