Parallel Multipipe Rendering for Very Large Isosurface Visualization

In exploratory scientific visualization, isosurfaces are typically created with an explicit polygonal representation for the surface using a technique such as Marching Cubes. For even moderate data sets, Marching Cubes can generate an extraordinary number of polygons, which take time to construct and to render. To address the rendering bottleneck, we have developed a multipipe strategy for parallel rendering using a combination of CPUs and parallel graphics adaptors. The multipipe system uses multiple graphics adapters in parallel, the so called SGI Onyx2 Reality Monster. In this paper, we discuss the issues of using the multiple pipes in a Sort-Last fashion which out performs a single graphics adaptor for a surprisingly low number of polygons.