Power Of The Dark Side

 I dance around flame
But am never burned

I am as quick as light 
but can never out run you

I take form in day
But am colour of night

What am I?

Seriously, if you answered anything other than a ****** (answer is below) I am sorely disappointed. So, for those who got the riddle this blog entry is about ****** mapping, essentially a way of creating ******s.

OK so the first step to ****** mapping is to create something called a depthmap which is essentially a texture that holds all the distances from a light source to all the vectors in a scene. The depthmap can be made by rendering the scene from the light’s perspective and take in the distances of all the vectors of all the objects in the scene to have ******s from the light source. Now that the depthmap has been created render the scene from the camera’s perspective. Now use a fragment shader to do calculations for lighting. Now determine if a fragment is cast in ****** by using the vertices from the light’s perspective. This can be done by determining if a fragment is a greater distance from the light source than is recorded in the depthmap, if so then it is cast in ****** otherwise it is lit as normal.

Answer: SHADOW

Sources
http://devmaster.net/posts/3002/shader-effects-shadow-mapping