VLSI AND GRAPHICS AT THE PIXEL LEVEL.

The computational bottlenecks in many interactive raster graphics systems are the pixel-Ievel calculations and not the display list traversals, geometric transformations or clipping computations. We examine several VLSI-based designs that focus on these pixel-Ievel calculations, noting the influence of the price-performance target on system design and component selection. We describe in detail the latest results from Pixel-planes, our experimental system optimized for algorithms in which many of the pixel-level calculations can be formulated as linear expressions (Ax + By + C) of the pixel's x,y address . We outline variations on the current implementation for greater generality or faster speed or lower cost. We show the effects of these changes on the· algorithms that are to be run on the alternative implementations. Bibliography Clark, J.H. and M.R. Hannah, "Distributed Processing in a High-Performance Smart Image Memory," Lambda (now VI..51 Design), 4th Quarter, 1980. * This research supported in part by the Defense Advanced Research Projects Agency, contract DAAG29-83-K-0148 (monitored by the US Army Research Office, Research Triangle Park, NC), the National Science Foundation, grant ECS-83-00970, and the Microelectronic Center of North Carolina. Graphics Interface '86 Fuchs, Henry, Jack Goldfeather, Jeff P. Hultquist, Susan Spach, John D. Austin, Frederick P. Brooks, Jr. , John G. Eyles, and John Poulton, "Fast Spheres , Shadows, Textures, Transparencies, and Image Enhancements in Pixel-planes," Computer Graphics, Vo!. 19, No. 3, July 1985 (Proc. SIGGRAPH 85). Goldfeather, Jack and Henry Fuchs, "Quadratic Surface Rendering on a Logic-Enhanced Frame-Buffer Memory," IEEE Computer Graphics and Applications, Vo!. 6, No. I, January 1986. Goldfeather, Jack, Jeff P.M. Hultquist, and Henry Fuchs, "Fast Constructive Solid Geometry Display in the Pixel-Powers Graphics System," to appear in Computer Graphics, Vo!. 20, No. 3, August 1986 (Proc. SIGGRAPH 86). Kedem, Gershon and John L. Ellis, "Computer Structures for Curve-Solid Classification in Geometric Modeling," Technical Report TR84-37, Microelectronic Center of North Carolina, Research Triangle Park, Sept. 1984. Poulton, John, Henry Fuchs, John D. Austin, John G. Eyles, Justin Heinecke, Cheng-Hong Hsieh, Jack Goldfeather, Jeff P. Hultquist, and Susan Spach, "PIXEL-PLANES: Building a VLSI-Based Graphic System," Proceedings of 1985 Chapel Hill Conference on VLSI, H. Fuchs, ed., Computer Science Press, Rockvile, Md. Vision Interface '86