Affects the amount and manner of which infected can spawn. This is a very important navigation attribute, use both wisely and with caution.
There are two primary uses:
Indicates that the area is not viewable by survivors, and allows the director to spawn flowing, or large waves of mobs. It is often used in blocked alleyways and other areas that survivors cannot view. The director can still create effective mobs without the use of OBSCURED, but they will usually be further outside the survivor PVS.
Allows infected to spawn even when there is line-of-sight to a survivor. Useful in unreachable areas with heavy fog, or areas with props that don't block line-of-sight in the engine, but still obscure the survivors view on all sides (e.g. bushes & leafy trees). Bot line-of-sight is also blocked to prevent omniscient behavior.
Tip:Props that have collisions disabled are always unable to block line-of-sight and will need the help of OBSCURED