An efficient volume-rendering algorithm with an analytic approach

We present a new approach, analytic isosurface rendering, for volume rendering. The isosurface of a cell can be modeled as an analytic function, and the intersection between a ray and the isosurface can be computed directly. An octree structure efficiently searches the cells containing isosurfaces. The octree is easy to implement and can be stored in a compact form. It needs extra memory space - at most 27/64 of the size of the original data volume. Front-to-back projection can easily be implemented under the octree structure. A union-find-based algorithm maintains the frame buffer efficiently. Experimental results show that a volume rendering program with our approach is very efficient and maintains the quality of the rendered images.