Depth of field

There are three depth of field looks you'll want to learn to achieve. The first is when the background is out of focus and the foreground is sharp, which is fairly easy, and the second, which is somewhat more difficult, is the opposite, where the background is sharp while the foreground is blurred. The third case is where both foreground and background are blurry but a telephoto style patch of the middle distance is sharp.

UDK gives us two ways to create Depth of Field, and these handle two of the above goals well. A Position based blur , being locked to a world location, is good for the third case, middle ground focus, but isn't dynamic. A Distance based blur method defocuses the background far better than it handles the foreground.

DOF can be applied in the scene based on a BSP volume created by the designer. If you use these, only the volume you are in yields a result to the screen draw, and if you are outside a volume you won't see its effects. On top of that, post-processing...