all you have to do is feed a greyscale mask into the alpha of a lerp, and have one lerp input be your texture multiplied by the image or constant 3 you want to use for colour variation and the other input be your plain image. here is a quick example in one of my materials where im using a mask to colorize the brick grout.…
ah i know what you want this is what i did with my vertex paint mask. i plugged this into the alpha of the lerp for all the textures i wanted vertex painted, the what it does it make the grout with some clouds variation fill in first by the vertex paint followed by everything else. I can set the intensity low on the mesh…