“…In the L-shaped condition ( Figure 1A), an observer was asked to perceptually match the sagittal length (L) of the L-shaped target to its lateral width (W). It was expected that the observer would require the length of the L-shaped target to be longer to match its width; that is, the aspect ratio (W/L) of the matched L-shaped target would be smaller than 1 (Loomis & Philbeck, 1999;Loomis, Philbeck, & Zahorik, 2002;Sauer, Braunstein, Andersen, & Bian, 2001). In addition, our previous studies have shown that the foreshortening of the L-shaped target is affected by the extent of the visible ground surface supporting the target .…”