Introduction - If you have any usage issues, please Google them yourself
Shadows are an important visual cue. Unfortunately, most real-time techniques f
computing shadows generate hard and, in the case of shadow-maps, aliased
shadows. We can soften the edges of the shadows by employing percentage-clos
filtering. In fact, a sufficiently large percentage-closer filter approximates soft
shadow boundaries well. High quality soft shadows, however, require a large
number of samples.