PERSPECTIVE 
In Antonio Canaletto’s Piazza 
St. Marco, linear perspective, 
size perspective, 
foreshortening, shadow, and 
interposition are all cues to the 
scene’s depth.

Of all the pictorial cues, 
perspective—–the 
characteristics of the 
projection of a scene onto the 
retina (or onto a two-
dimensional plane) as a 
function of the depth of the 
scene—–is best known. 
Perspective includes more than 
linear perspective, the aspect 
of perspective that is perhaps 
most familiar. Linear 
perspective refers simply to the 
fact that parallel lines that 
recede into the third 
dimension project to the eye as 
converging lines. Another 
aspect of perspective is size 
perspective, which refers to 
the fact that objects of equal 
size at varying distances project 
images whose visual angles are 
inversely proportional to their 
distance. Gibson was referring 
to a special case of size 
perspective when he 
introduced the term texture-