Six Point Projection 

Five point projection will only render a 180 degree field of view. To render the entire 360 degree field, two circular picture planes are needed.  The central vanishing point in the new picture plane represents the polar opposite to the central vanishing point in the first plane.  The four vanishing points on the circumference of the new plane are not new; merely a reverse iteration of the vanishing points that already exist in the first plane. 


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