Lightgrid

Lightgrid or volumeric lighting - a data structure used to store static lighting for models. Lightgrid are created during LIGHT phase each time map is compiled.

Each cell of lightgrid stores this information:

• Ambient light RGB
• Diffuse light RGB
• Light vector

When rendered, model sample it's position at lightgrid and find average ambient and diffuse lighting to be applied during shading.

Default lightgrid cell size in game units is '64 64 128'. It can be customized with "gridsize" worldspawn key. Most of Blood Omnicide maps using lightgrid size '32 32 32' or '32 32 64'.