Rotation of the camera
From A conversation about the brain
here and here). Looking at object A with object B currently imaged on peripheral retina and having the motivation to fixate B leads to a saccade to B. A series of such sensory+motivational contexts would allow an observer/camera to alter fixation from any object to any other and hence form a representation of 'where' each object is in the optic array.
Back to 3D vision.
- Glennerster, A., Hansard, M. E., & Fitzgibbon, A. W. (2001). Fixation could simplify, not complicate, the interpretation of retinal flow. Vision Research, 41(6), 815-834.