Most people don't know this because it's not documented in the latest help file. Also, sometimes, your model will share the same mesh of different parts of the model (EI: Your helmet has a 3/4 different sub-objects which are defined as different material, people would like to apply different colors to represent said…
if i export all my highpoly separately according to material definition(which i always do anyways), wouldn't applying vertex color to highpoly become redundant ? also, applying vertex color would mean importing a dense highpoly mesh back to maya/max is a hassle. the base color u see here was baked in xnormal pretty fast.…