accessing strand index information via expressions

 
 
 
Posted by:phornetca
Data created:25 June 2019

If you've ever looked at a cat's hair, you'll notice that the color will change along the length of the hair strand itself.  If you compare one hair to another hair directly next to the first, there is usually a slight variation in color placement along the length of the hair strand.  I'm trying to replicate this look.

Is there a way to access the strand index via expressions so that I can use it as the seed value for randomizing the placement along a strand.

I'm open to pretty much any ideas on how to accomplish this variation in placements of colors along a strand length, if anybody has any better ideas.

Hi,

In Ornatrix you can add randomization to the hair colors in a per strand basis and in a per strand vertex basis. However, this can vary depending on the renderer you are using. For example, Ornatrix provides the renderer the UVs and hair strand information, in VRay you would use the Fur Sampler to use this information for shading. 

In Redshift you would use the Hair Position node to do the same as VRay.

In Redshift for Maya (Not implemented in Max yet but I will push this) you can use Per Strand channels to create any type of masks that you can use in the shading network, including channels generated with the GenerateStrandData modifier using expressions, you can find more info about expressions in the same doc page. We plan to implement this in all renderers. 

Jeordanis Figuereo (Product Designer. EPHERE Inc.)