I started working on modeling a horse. Targeting UE4, I created to high poly sculpt, and proceeded to retopo the mesh for use in engine.

Then I began working on a shader for UE4 that would allow the customization of coat colors and patterns. Using a lower resolution gray-scale image as a mask different feature areas of the horse can be colored. I blurred the mask in Photoshop, and then increase the contrast in the shader. This allows me to add the value of a parameter to the mask to increase or decrease the feature areas.

I use a detail texture of small hairs, rather than a full size map, to reduce the texture memory footprint. For the detail hair texture, each hair has a slight variance in value, that i use to define how the hair areas should blend. By increasing the contrast of the detail hair and then adding that to the mask of the hair, I can create a blend between color areas that keeps each individual hair a sold color.