The Angular fading coefficient is a a number between 0% (ka = 0) and 100% (ka = 1) that determines how the light intensity decreases as it approaches the edge of the light cone. When this value is 0, the light inside the cone is uniform. If this value is greater than 0, the light intensity decreases as you approach the cone margins of the cone. The intensity is determined by the following equation:
I=(cos C)kawhere C is the angle between the light direction and the direction from the spotlight to the area being lighted, and ka is the angular fading coefficient.
