A computer animation system is discussed which employs interactive techniques and presents a unified approach to the graphical display of complex three dimensional data. The system facilitates the generation, manipulation and display of highly detailed data with the aid of interactive devices and a video interface to a standard color TV monitor. The system enables the animator to create a variety of objects (including texture) and to specify the necessary transformations for animation sequences. A run length processing technique combined with a brute force Z-buffer algorithm has been newly designed and implemented that can handle the intersection of several million faces, lines and points. This makes possible a full range of visual cues to simulate fire, smoke, water and complex 3-D texture such as grass, hair and bark. Basic concepts and approaches are described. The display algorithm and the procedure model to generate texture are presented and the implications of the system for computer animation are discussed. Extensions to the system are outlined which include a unique graphics display processor currently under construction that includes a partial implementation of the display algorithm in hardware.

An animation software system has been developed at The Computer Graphics Research Group which allows a person with no computer background to develop an animation idea into a finished color video product which may be seen and recorded in real time. The animation may include complex polyhedra forming words, sentences, plants, animals and other creatures. The animation system, called Anima II, has as its three basic parts: a data generation routine used to make colored, three-dimensional objects, an animation language with a simple script-like syntax used to describe parallel motion and display transformations in a flexible, scheduled environment, the Myers algorithm used in the visible surface and raster scan calculations for the color display. This paper discusses the requirements, the problems, and the trade-offs of such a system. An overview of research in the area is given as well as the design and implementation highlights of the Anima II system.