Shader variations for Xgen Interactive groom

[robin.isola]

Hello,

Is there a way to apply different shaders on individual hairs or strands with Xgen interactive grooming ? I know there is a way to bring color variations with classic Xgen but I can't find anything for interactive grooming.

Or at least how to apply a shader only to a selection made with the select brush for instance ?

[robin.isola]

There must be a way to do something like that, I can't imagine interactive grooms would not allow a more in depth texturing/lookdev of the hairs than just a basic PBR hair shader. 🤔

[robin.isola]

I really need to find a way to achieve that, so any help or insight is appreciated. Is my description of my issue not clear enough ? Can I make it more understandable ?

Thanks.

[mspeer]

Hi!

You can apply any shader network to the hairs (XGen description) as for other objects too, which allows for any kind of variations.

[robin.isola]

Hey, thanks for taking the time to answer,

So, I will rephrase my issue since I apparently wasn't precise enough, my fault. 

I have a fairly complex groom made with Xgen Interactive grooming, made of several interactive splines (wich I assume is the equivalent of descriptions in classic Xgen), but what I'm trying to achieve is to bring color variations within each of these interactive splines that make up my groom. Meaning I need to be able to control the global color of individual hairs. The idea here is blending white hairs within my groom, since the character I am working on is getting at that glorious Salt & pepper stage.

I can of course apply different shaders to my "descriptions" (Interactive splines) but I cannot find a way to apply said shaders to specific strands of hairs within those "descriptions".

The only way I managed to bring variations is with a basic ramp mapping in the color attributes of my shader, but it only allows for local variations, not globally shade entire individuals hairs as white ones.

I hope I'm making more sense now 😉

[mspeer]

Hi!

You can't assign a shader to individual hairs (as far as i know), but as every hair has a unique position at the object you should be able to achieve the same effect with textures/UVs.

[robin.isola]

That was my understanding yes, but for what I've seen, only the aiStandardHair allows you to map a texture in such a way, and I'm not very found of that shader for the way it deals with specularity/roughness, to have some decent contrast and deep black on shadow areas the roughness has to be pretty low or else it feels very flat, but that gives the hairs an almost wet look and way to "perfect". Like straight out of a shampoo commercial 😬

So far I've been using the hairPhysicalshader from Maya, but I don't think the 2 diffuse inputs (root and tip) work with Uvs and textures. Or maybe I'm missing something ?