Computer graphics for half-tone three-dimentional object images

摘要

A system is described for displaying studio-quality television images of objects described by a set of closed polyhedra. The objects are defined by a series of opaque planar surfaces which may obscure and intersect each other. The image description lists are passed through a scan-conversion, hidden surface removal and shading process and are converted to a real-time television signal. Display occurs through a normal T.V.system.Resolution is 512 lines by 512 dots with a color definition of 15 bits (over 32,000 colors). Generation of the display list is through an interactive language based on a tablet input and three-dimensional rotation of the boundary polygon. Color definition is through an electronic "palatte," also interactively. The system incorporates shading of the surfaces based upon the angle of the normal to the surface to the observer.The system is resident on an 8K 16-bit minicomputer which accesses a hybrid rotation array.