Fig. 2.

Barber-diamond stereogram. A stereo pair for one of the depth-ordering conditions in our main experiment (depicted schematically in Fig. 1b,c) is presented. Cross-fusing the two images promotes an illusion of depth ordering between the square-wave grating and the surrounding textured regions. The regions located up-right and down-left relative to the grating should be perceived as foreground surfaces. Conversely, the regions located down-right and up-left relative to the grating should be seen as background surfaces. The zero-disparity grating should be perceived to lie in the middle depth plane.