Node: ShadowBox
For complex cinematic shots where tight control of the shadows is desired, adding a ShadowBox will confine the rendered shadow to a smaller area of the scene. This allows for shadows of higher resolution in desired locations.
ShadowBox Usage
ShadowBox nodes are rarely needed, but when one is present in the scene, the shadow will be limited to the region inside the box improving performance and shadow quality. This special node is just a Standard Primitive Box with the name ShadowBox applied. Position, Rotation and Scale can be animated like any other bone. If more than one ShadowBox is visible, there is no defined preference, and the shadows in the scene may flicker erratically.