Sprites are being drawn that are out of view

[Noggin]

I have a func_smokevolume in the sewers yet theyre being drawn when youre above ground, it hurts performance, is there a way to prevent this?

http://s90652007.onlinehome.us/tf2/ctf_powerhouse_sprites.jpg

[dirtyminuth]

Two ideas spring to mind:

1. Make sure that there isn't truly vis from ground level to the smoke.

2. Look into occluders. They might prevent func_smokevolume ents from being rendered.