Speeding Up Isosurfacing: The Matryoshka Algorithm

Abstract

We propose a hybrid algorithm for isosurface visualization that embraces both polygon rendering and direct surface rendering concepts. It uses raytracing to achieve high image quality but avoids the associated empty ray traversal. At the heart of the algorithm is a caching strategy resembling the famous Russian stacking dolls, that allows the processing of cells of interest from any viewing orientation. We use an optimised interval tree to extract these cells from the volume. In that respect, we propose two versions, combining grouping of cells and ordering. In comparison to the classic version of the interval tree, the memory overhead decreases but the increasing in the query time is marginal.