Volumetric (or realistic) fog is a fog that looks WAY better then the zoneinfo fog (i.e. the bluish tint you get when you're underwater, that's zone fog) Volumetric fog is a definite eyecatcher and very appealing in even the most odd places.
But, before we start, you must have bVolumetricFog enabled. So open your unrealtournament.ini and find which video driver you use, (if you scroll down, you will start to see [software rendering] [Direct3D] ect..) and make sure bVolumetricLighting=True. Once that is finished, you will be able to see "realistic" fog!
Now, open up Unrealed, and make a plain room with just a zoneinfo in it. Then, go into the zoneinfo's properties (Zoneinfo -> bFogZone) and make bFogZone True, don't edit anything else. Then, make a light and put it in the center of your room. Then, go into it's properties -> Lighting, and edit the last three bars below (Volumetric Brightness, Volumetric Fog, Volumetric Radius) set volumetric radius to 200, Volumetric Brightness to 100, and Volumetric fog to 200. Then, rebuild the map and you should have fog!
Feel free to edit the values of Volumetric Brightness, fog, and radius. Try experimenting to see what happens! (For further looking at what the fog looks like, see my map CTF-Close Combat or my screenshots of DM-Tarydium Caves

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