Techniques for interactive raster graphics

Abstract

The visual quality of raster images makes them attractive for applications such as business graphics and document illustration. Such applications are most fully served using interactive systems to describe curves, areas and text which can be rendered at high resolution for the final copy. However, to present such imagery in an interactive environment for moderate cost is difficult. Techniques are presented that provide solutions to the problems of scan conversion, screen update, and hit testing for a class of interactive systems called illustrators. The design rests on the use of software display file encoding techniques. These ideas have been used in the implementation of several illustration programs on a personal minicomputer.