Screen shots (cropped) showing the various depth cues used. (a) Training cube disambiguated by disparity and occlusion cues. (b) Corresponding test cube, presented monocularly. (c) Training cube disambiguated by occlusion, depth-from-shading, internal occlusion, and haze. (d) corresponding test cube. Cubes a and b are representative of those used in Experiments 1, 2, and 3. Cubes c and d are representative of those used in Experiment 4. Screen shots also show the location of the fixation square and path of the comparison dot for a “top” cube in Experiments 1 and 4. The background was black in the experiments.