To return a position (ASL Height)'s approx. fog level
private _getFogPowerASL = {
fogParams params ["_fogPower","_fogDecay","_fogHeight"] ;
private _height = _this - _fogHeight;
(_fogPower * 0.5 ^ (_height * _fogDecay / 2.45) max 0)
};
(AGLToASL (positionCameraToWorld [0,0,0]) # 2) call _getFogPowerASL;
Note that, this could return >1 value if fogDecay is not 0.