Shaded Picture System

Shaded Picture System
ManufacturerEvans & Sutherland Computer Corp.
Typecomputer graphics terminal and 3D display processor
Release dateOctober 1973; 51 years ago
Display256 by 256
Graphicsraster, black and white

The Shaded Picture System was a 3D raster computer display processor introduced by Evans & Sutherland in October 1973.[1]

The Shaded Picture System was the first general-purpose, commercially available raster computer graphics display processor capable of real-time, shaded 3D graphics. It could only display black and white graphics at a resolution of 256 by 256.[2] It was extremely expensive, and very few units were ever sold.[3]

History

An image of a cube generated by the first algorithm at the University of Utah in 1967.
A color image of a church generated by the FORTRAN simulator of the Watkins algorithm at the University of Utah in 1970.

The principles of shaded, hidden-line true 3D graphics were pioneered at the University of Utah in 1967.[4] However, this algorithm was slow and would take several minutes to produce an image. In 1970, Gary Watkins developed a FORTRAN simulator of a faster algorithm that would theoretically generate shaded 3D images in real-time, "if implemented in suitable hardware".[5][2] The simulator itself was still not capable of real-time shaded 3D image rendering. Evans & Sutherland developed a functional prototype of this "suitable hardware", which was later sold as the Shaded Picture System in 1973.[2]

About a year earlier in 1972, Evans & Sutherland sold the first and only CT1 to Case Western Reserve University.[6] The CT1, or Continuous Tone 1, was a specialized image generator, not meant as a marketable or mass-produced product. At the time, the CT1, along with G.E./NASA's upgraded Electronic Scene Generator from 1971,[7] would have been the only real-time raster graphics systems sold to customers comparable to the Shaded Picture System, although both the CT1 and Electronic Scene Generator were intentionally produced as one-off products and specialized for the needs of their customers.[6] The Shaded Picture System, in contrast, was intentionally marketed.[2]

An image of a Klein bottle generated by an E&S Picture System (left) and displayed shaded and in color on the frame buffer (right) in 1975.

In early 1975, Evans & Sutherland demonstrated a random-access video frame buffer using relatively low-cost semiconductor memory, which was much more capable than the Shaded Picture System.[8] When interfaced with a (non-shaded) E&S Picture System, the frame buffer had a resolution of 512 by 512 in grayscale and partial color capabilities. By the end of 1975, this frame buffer was commercially available.[9]

See also

References

  1. ^ Staudhammer, John; Eastman, Jeffrey F.; England, James N. (1974-12-01). "A fast display-oriented processor". SIGARCH Comput. Archit. News. 3 (4): 17–22. doi:10.1145/641675.642093. ISSN 0163-5964.
  2. ^ a b c d Eastman, Jeffrey F.; Staudhammer, John (1974-12-01). "Computer display of colored three-dimensional objects". SIGARCH Comput. Archit. News. 3 (4): 23–27. doi:10.1145/641675.642094. ISSN 0163-5964.
  3. ^ Crow, Franklin C. (1976). The aliasing problem in computer-synthesized shaded images (PhD thesis). The University of Utah.
  4. ^ Wylie, Chris; Romney, Gordon; Evans, David; Erdahl, Alan (1967-11-14). "Half-tone perspective drawings by computer". Proceedings of the November 14-16, 1967, fall joint computer conference on - AFIPS '67 (Fall). New York, NY, USA: Association for Computing Machinery. pp. 49–58. doi:10.1145/1465611.1465619. ISBN 978-1-4503-7896-3.
  5. ^ Watkins, Gary Scott (1970). A real time visible surface algorithm (PDF) (PhD thesis). The University of Utah.
  6. ^ a b "History of Evans & Sutherland Computer Corporation". FundingUniverse. Retrieved 2024-11-09.
  7. ^ Christianson, David C. (1989-08-01). "History of visual systems in the Systems Engineering Simulator". Graphics Technology in Space Applications (GTSA 1989).
  8. ^ Kajiya, James T.; Southerland, Ivan E.; Cheadle, Edward C. (1998-07-01), "A random-access video frame buffer", Seminal graphics: pioneering efforts that shaped the field, Volume 1, vol. 1, New York, NY, USA: Association for Computing Machinery, pp. 315–320, doi:10.1145/280811.281022, ISBN 978-1-58113-052-2, retrieved 2024-11-09
  9. ^ Datamation (PDF). December 1975. p. 51.