Is there a way to assign materials based on a color map in blender? I am trying to add Snow stuck to the bottom of a pillar and have created a procedural snow effect using substance designer, but I'd like to have the ability to set the pillar material using blender as opposed to adding one using substance designer as well ass add subsurface scattering to the snow which is easier using Blender, Is there a way to assign either different materials based on the colour map or use it as a mask to combine different materials. I know I could use Substance Painter to assign materials based on colour but as I mentioned I prefer using blender for subsurface scattering and would also like to avoid having to use multiple programs for everything if I could, by doing this in Blender I'd only need to use Blender and maybe load up Substance Designer to generate a few other once using different seeds so as to avoid too much repetition but when using only one I don't even need to load that up.
You may be able to use mix shader nodes

I achieved this result;




Using this node setup;



And these black and white textures (painted in blender, directly on the object);



.blend file here;



Effectively, what this does is uses the black (0) and white (1) or gray (some decimal value in between) as a factor for a mix shader. This mixing can be added to as many times as you like with this setup.