Image bm863.GIF Penumbra Angle
The penumbra angle element determines the penumbra angle of the active light cone, if the light in question is the spot light. The penumbra is the outer spot light cone. The inner part encloses the light cone angle. If the penumbra angle is smaller than the light cone angle, then a light cone without any penumbra is used. The penumbra angle is expressed in radians, the default setting being 0.

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