Depth Cues: Creating the Illusion of Depth - Flash 3D: Animation, Interactivity, and Games - page 22

Our atmosphere scatters light, which affects our depth perception. Figure 2.8 simulates
this occurrence. Both men are the same size and distance from the viewer. The right
image has been blurred, and the overall coloring is blended into the background. With
these changes, the man on the right appears slightly farther away than the man on the
left. This depth change in coloring and clarity is known as aerial perspective.
Figure 2.8 Aerial perspective
Our last visual depth cue is texture gradient. This borrows concepts from linear per-
spective and relative size. Surfaces such as brick walls, tiled floors, and even waves
in the ocean have a texture to them. The farther away we are from a surface, the
smoother and denser its texture appears (Figure 2.9).
Figure 2.9 Texture gradient