Wednesday, December 19, 2007

Renderer Design

Here is an example:
5. do global illumination with the normal map
6. do PostFX


Unknown said...

I'm confused about what you mean by
"shadow collector" and a "light buffer" here.

Could you eloborate?

Wolfgang Engel said...

The shadow collector is a screen-space texture that holds all the shadow data from all shadow sources. It is usually in screen size or MSAA'ed screen size, which means 1280x720 or 1600x1200.
Light buffer keeps light data only. That means only the light properties of the lighting equation. This light buffer is later used to re-construct the lighting equation.

Unknown said...

Could you elaborate any further ?
First, how do you handle alpha-blend objects (ignore and sample opaque shadow ? or shadow map separately).

Also, why keep them separate if you are lighting deferred ? If you keep them separate, how does the shadow value match to the appropriate lighting value (ie how do you match up a shadow value for light N to the lighting value for for light N). Or are you just approximating ?