Abstract: A process for the generation of a computer image of a coated, three-dimensional object involves preparing a coating comprising a relevant coating layer with variable layer thickness on one or more test panels; taking a plurality of measurements of one or more optical surface properties as a function of the layer thickness of the relevant coating layer; storing the optical data in a datafile with assignment of the layer thickness of the relevant coating layer; facetting the visible surface(s) of a three-dimensional object by computer into a sufficient number of flat polygonal areas each being sufficiently small for the sufficiently accurate description of the surface topography; assigning layer thickness of the relevant coating layer and associated optical data in each case to each individual polygonal area by computer; and assembling the polygonal areas into a computer image of the three-dimensional object.