A Cellular Architecture for Ray Tracing

Abstract

"We propose in this paper a massively parallel machine dedicated to image synthesis by discrete ray tracing techniques. This machine is a four-stage pipeline, the last stage being a bidimensional cellular array with one cell per pixel. Two main phases describe its behaviour: Loading into the cellular array of the objects of the scene to be displayed, after having been transformed into sets of planar polygons, and then into voxels. Cellular ray tracing over the fully distributed scene.The first phase allows us to see this machine as a massively parallel (not realistic) rendering unit: at the end of the loading phase: objects are fully identified pixel per pixel in the cellular array. Then, we have only to display the computed visual features (by means of Gouraud or Phong-like incremental methods during the loading phase).The second phase increases the image quality by executing the ray tracing algorithm in a very special way, i.e., completely distributed all over the many cells of the array. In that phase, objects are seen as split into voxels into a virtual 3D memory space. The machine is an attempt to bring a dramatic answer to the problem of performance, taking into account not only the computational power required for image synthesis by using a massive parallelism, but also the realization costs by using very regular structures, which make it a VLS1-oriented architecture."