Genma Saotome, on 23 October 2014 - 09:20 AM, said:
How close together is too close?
Yes, it's caused by the two textures being layered so close and the particular solution OR takes to applying z-bias.
If I am reading the code right, it moves items forwards (towards the camera) by up to 1mm (technically very, very slightly more due to near-plane scaling). Take this as a minimum separation needed, however, since the accuracy of the depth buffer depends on the viewing distance so it's not always obvious what the closest something can be without error.