1. A computer vision method comprising: deriving, with a processor, a relationship of spatial and temporal image derivatives of an object to bidirectional reflectance distribution function (BRDF) derivatives under camera motion that provides an image sequence; deriving a quasilinear partial differential equation for solving surfaced depth for orthographic projections using the relationship of spatial and temporal image derivatives to bidirectional reflectance distribution function (BRDF) derivatives; solving the surface depth from the quasilinear partial differential equation; and reconstructing an image of the object from the solving of the surface depth for orthographic projections.