the finer the texture is, the further away
texture gradient
hazy objects are farther away
relative clarity
objects that block each other are closer
interposition
taller is farther away
relative height
objects farther away from the thing you are looking at will move the same way it is, while those that are closer will move the opposite way
relative motion
parallel lines appear to converge in the distance
linear perspective
dimmer lighted things are farther away
light and shadow
objects moving toward you look closer while objects moving away look farther
motion perception