The 3D assets of the big dam and the camp were essential as they're seen from many points of view in different lighting conditions . Rodeo FX CG crew had frequently to provide diffuse , color , bouncing light , key light , occlusion pass to matte painters . In this case the normal pass was helpful to add color and material variations to faces of the dam , according to their orientation in space . The whole landscape was painted using several pictures of deserts and rocky mountains .