this would happen to me quite often with day of defeat and cod 5 waw i would get an enhanced depth perception from it
im suspicious the way they achive this is a focus algorithm as you can see here:
so has anyone had a 3d perception on a flat game?
edit:
ive been checking the game and i noticed every time i get virtually killed the 3d effect amplifies
what happens after you die is that the unfocus effect with disctance is huge which explains the 3d amplification