is there Z-offset options?

[MichaelJPCT]

i couldn't find any.

[EgonOlsen]

Depends on what you mean with that...?

[MichaelJPCT]

i want Z-offset (or depth-offset) to help resolve 2 (nearly) co-planar polygons, one should be seen , the other should be hidden. although moving one of them a little closer can have effect, but with Z-offset the result can be better in some cases.

[EgonOlsen]

Then no. You have to do that in a shader. However, I think that fiddling around with depth to get something to work indicates that you are on the wrong track...