Hardware Assistance for Z-Buffer Visible Surface Algorithms

The well-known z-buffer algorithm for solving the visible surface problem has a number of points in its favor, the main one being that it can be very efficiently implemented at little additional cost in many existing frame-buffer systems. The traditional software implementation of the algorithm assumes explicit initialization of both the image buffer and the z-buffer before each image is generated. We will describe a simple technique for synchronizing initialization and image generation so the two can be performed in parallel, effectively elimination the time needed for explicit initialization of the frame buffer. The technique assumes a modest investment in additional hardware within the frame buffer.