Sets the clipping bounding box for the model. This box is used for the culling of models in the game for optimization. A model will be culled as soon as the clipping bounding box is no longer in view of the camera. If the coordinates of the this clipping bounding box are all zero, $bbox is used instead.
$cbox (min x) (min y) (min z) (max x) (max y) (max z)