Shadow groups

Shadows group is a combination of _cs (cast shadows) and _rs (receive shadows) entity keys used to control how entity cast lightmap/vertex light shadows. A numbers should be used for shadows groups (1, 2, 3, 100, 1000 etc.), negative values are allowed.

Shadows groups are applied during lightmapping of entity using this rules:


 * 1) Receive shadows is 1: only receive shadows from objects with cast shadows 1 (the worldspawn cast shadows).
 * 2) Receive shadows is > 1: only receive shadows from objects with same abs(cast shadows) and worldspawn.
 * 3) Receive shadows is < 1: only receive shadows from objects with same abs(cast shadows) and no worldspawn.

By default worldspawn and func_group have cast shadows and receive shadows 1. All other entities have cast shadows 0 and receive shadows 1.

=See also=
 * Lightmap
 * Vertex lighting