Vanishing points: (a) one vanishing point, (b) two vanishing points, and (c) three vanishing points. Each blue cube front marks the Cartesian dimensional rectangular coordinate system of x, y, and z axes and the visual perception of the mutually perpendicular structure between them. In various modern city buildings and green landscapes, photographs and actual scenes from different perspectives can have three vanishing point types.
Songnian et al. BMC Neuroscience 2014 15:50 doi:10.1186/1471-2202-15-50