“Techniques for interactive raster graphics”

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.

1. Baudelaire, P., Flegal, R.M., and Sproull, R.F., Spline curve techniques, Xerox Palo Alto Research Center Internal Publication, (December 1977).
2. Erdahl, A.C., Displaying computer-generated half-tone pictures in real time, University of Utah Computer Science Technical Report, Salt Lake City, (1969), 4-14.
3. Freeman, H., Computer processing of line-drawing images, ACM Computer Surveys, Vol. 6, No. 1, (March 1974), 57-97.
4. Laws, B., and Newman, W.M., A gray-scale graphics processor, using run-length coding, Proceedings of the IEEE Conference on Computer Graphics, Pattern Recognition, and Data Structures, (May 1975).
5. Newman, W.H. and Sproull, R.F., Principles of Interactive Computer Graphics, 2nd edition, McGraw Hill, New York, 1979.
6. Pitteway, M.L.V., A simple data compression technique for graphics displays or incremental plotters, Symposium on Computer Processing in Communications, (April 1969).
7. Shoup, R., Color table animation, Computer Graphics, Vol. 13, No. 2, (August 1979), 8-13.
8. Shoup, R., Some experiments in television graphics and animation using a digital image memory, Presented at the 13th Television Conference of the SMPTE and published in Digital Video, Vol. II, SMPTE, Scarsdale, New York, 1979, 88-98.
9. Smith, A.R., Paint, Technical memo #7, Computer Graphics Lab, NYIT, Old Westbury, New York, 11668, (July 1978).
10. Smith, A.R., Tintfill, Computer Graphics, Vol. 13, No. 2, (August 1979), 276-283.
11. Sproull, R.F. and Newman, W.M., The design of gray-scale graphics software, Proceedings of the IEEE Conference on Computer Graphics, Pattern Recognition and Data Structures, (May 1975).
12. Sproull, R.F., Raster graphics for interactive programming environments, Computer Graphics, Vol. 13, No. 2, (August 1979), 83-93.
13. Thacker, C.P., McCreight E.M., Lampson, B.W., Sproull, R.F., Boggs, D.R., Alto: a personal computer, Xerox Palo Alto Research Center Internal Publication, (July 1979).