They fill hidden parts according to symmetries they find in the object’s geometry or make use of model’s textures or user-defined input if there is no symmetry.
> For areas of the object that do not satisfy the criteria of geometric symmetry and appearance similarity, such as the underside of the taxi cab in Figure 1, the assignment defaults to the stock model appear- ance. The assignment also defaults to the stock model appearance when after several iterations, the remaining parts of the object are partitioned into several small areas where the object lacks structural symmetries relative to the visible areas. In this case, we allow the user to fill the appearance in these areas on the texture map of the 3D model using PatchMatch.
