z Buffer in viewport

[hedphelym]

Hi,
I was looking for a way to view the zbuffer in the viewport for debugging our scenes.

Also - I assume I can send this to 3dsmax and use it for both realtime viewport and while rendering? This would be a very good tool for us.

I saw the youtube video here and it seems to be what I need:

http://www.youtube.com/watch?v=aUL3Ds_dZS4

I need help on how to replicate this.
I'm a c# coder and maxscripter, but mental mill and shader writing is a bit new to me to be honest.

Any help is appreciated,
thanks in advance.