Six monocular cues for depth perception?

Answer 1

Relative Size: All things being equal, more distant objects look smaller than closer objects.

Texture Gradient: The texture of objects becomes less apparent as objects move farther away.

Interposition: One object that's closer blocks our view of an object behind it. From this fact, we know which object is closer and which is farther away.

Linear Perspective: The outlines of rooms or buildings converge as distance increases, a fact exploited by artists in perspective drawing. The lines never actually meet but they appear to from a distance.

Height in Plane: In a scene, distant object tend to appear higher, and nearer objects lower.

Light and Shadow: Objects cast shadows that give us a sense of their three-dimensional form