A contour display generation algorithm for VLSI implementation

Recent articles have discussed the current trend towards designing raster graphics algorithms into VLSI chips. The purpose of these design efforts is to capture some of the real-time animation capability found in vector graphics systems. Currently, real-time vector graphics animation is limited primarily to operations involving coordinate transformations. In order to enhance this animation capability, frequently encountered vector graphics algorithms that require the high speed, parallel computation capability of VLSI must be identified. Real-time contour display generation from grid data is one such algorithm. This paper describes the specifics of a contour display generation algorithm, the architectural framework of a processor that performs this algorithm and the architectural requirements of such a processor. The contouring algorithm is based on a data structure, the contouring tree, whose regularity and amenability for parallel computation make it an ideal candidate for VLSI. The architectural framework for a contouring processor chip that performs this algorithm for the real-time environment of interactive graphics is discussed, particularly the issues of memory size and data distribution. A model of the contouring process is created in order to determine the necessary physical parameters of the contouring processor in this architectural framework. Conclusions are drawn concerning the feasibility of producing a VLSI chip that performs this contouring algorithm.