Point-based rendering of non-manifold surfaces

We are concerned with producing high-quality images of parametric and implicit surfaces, in particular those with non-manifold features. We present a point-based technique for rendering implicit surfaces that uses octree spatial subdivision with a natural interval exclusion test that guarantees that no parts of the surface are missed. This allows us to render non-manifold implicit surfaces at speeds comparable to parametric surfaces. We also derive criteria that guarantee complete pixel coverage of the surface. The point-based method allows for hidden surface elimination using a z-buffer and shadow casting using a shadow buffer We illustrate the technique with a number of surfaces, and discuss its advantages and disadvantages.