/* 04.03.1991 */
volume ACDepthC (
			float	kFixed = 1.0;
			float	kVar = 0.0
			)
					
{	float	fixed = 1.0;
	float	dist;

	if (kFixed > 1.0)
		fixed = kFixed;
	dist = depth(P);
	Ci = Ci / (fixed + kVar * dist);
}