Instead of actually upsampling the mesh, is it possible to make the mesh look smoother by interpolating the normal vectors used for lighting? Is it possible to do all the upsampling at render time on the graphics card?
@HelloWorld Yes, you can play tricks with the shading of the surface to give it a smoother appearance, though such tricks have obvious limitations. For instance, the silhouette of the object will still look jagged. Rendering algorithms that involve sophisticated global illumination (such as reflections and caustics) may exhibit significant aliasing/artifacts. Algorithms that use such a mesh for animation/simulation may also exhibit serious artifacts. Etc. At some point, there's no completely satisfactory alternative to refining the mesh in some way. This means either introducing additional polygons, or introducing additional degrees of freedom in the interpolating bases (e.g., using Bezier patches instead of linear elements).