Exploiting data coherence to improve parallel volume rendering

We have implemented a parallel volume renderer that successfully manages work and data distribution by exploiting data coherence-the tendency of neighboring pixels to use the same data during rendering, particularly when rendering volume data. This flexible, powerful renderer uses ray-casting on a Fujitsu AP1000 to generate high-quality images of volume data sets with other geometrically defined structures, such as a set of coordinate axes or a world map. This article focuses on our schemes for work and data distribution. Using image-space work distribution to partition a 2D image among processing nodes, and distributed virtual memory to assign 3D volume data, this renderer effectively and efficiently parallelizes volume rendering.<>