model://ground_plane model://sun 0 0 0.5 0 0 0 1 1 1 0 1 1 1 0 1.5 0.5 0 0 0 0.5 1 0.5 0 -1.5 0.5 0 1.5707 0 0.5 1.0 2 0.5 1.0