Specifies an activation distance for a sound effect associated with an area, e.g. chirping birds, the guy stuck in the water tank at Salerno, crickets. The object itself is created in a level's StaticObjects.con file, the Environment.con file then Runs the sound effect file (e.g. river.con), and the sound effect file creates the sound effect object and defines its TriggerRadius. Bodies of water have a set of points defined for them with AddLinePoint.
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