add material IDs to every material in scene?

V-Ray V-Ray for 3ds Max General
10

www.chaosgroup.com/en/2/material_ID_channel.html

This is the sort of thing that would be ideal. A little swatch on the V-ray material that you pick your matID colour in, and viola
(Is that V-ray for sketchup that has the feature?!!)

I have no qualms in revealing I’m using the immensely mighty… Photoshop CS5. Because I mainly only do stills.