Hints about categories help perception. Expectation allows greater responses from cells sensitive to certain orientations, for example. Ambiguous stimuli tend to be seen in ways biased by the context. Depth perception has monocular and binocular cues. Monocular cues include ones in pictures, such as size and interposition, perspective, texture, haze, shading and height up to the horizon.
Some people think it affects perspective's effects in vision a lot.
Some do not. Such as Miss Piggy and moi.