I have asked this before, and I used to use xoliul shader, but it does not seem to work for 3ds max 2013 and his website seems to be down :S
I have found another one called 3-point viewport shader, but that will not install and their support email has not replied for afew days now.
I have also been using Marmoset which is awesome for testing normals ect, but I can't afford a licence at the moment and my trial has ran out.
Does anyone know a good viewport shader that works in 3ds max 2013 that I can use?
Replies