The first brain structure processing the information before it is sent to the visual cortex is the lateral geniculate nucleus in the thalamus. This structure will mostly take care of the mathematical perspective of what is being seen. It calculates the velocity of the image in space, if it's getting closer or further away, it calculates the relative position of the major elements to the principle plane, and it controls the focus of the eyes accordingly to calculations related to the plane of interest.
