Shaded Picture System
{{Information appliance
| manufacturer = Evans & Sutherland Computer Corp.
| release date = October 1973; 51 years ago
| graphics = raster, black and white
| type = computer graphics terminal and 3D display processor
| display = 256 by 256
}}
The Shaded Picture System was a 3D raster computer display processor introduced by Evans & Sutherland in October 1973.{{Cite journal |last1=Staudhammer |first1=John |last2=Eastman |first2=Jeffrey F. |last3=England |first3=James N. |date=1974-12-01 |title=A fast display-oriented processor |url=https://dl.acm.org/doi/10.1145/641675.642093 |journal=SIGARCH Comput. Archit. News |volume=3 |issue=4 |pages=17–22 |doi=10.1145/641675.642093 |issn=0163-5964|url-access=subscription }}
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.{{Cite journal |last1=Eastman |first1=Jeffrey F. |last2=Staudhammer |first2=John |date=1974-12-01 |title=Computer display of colored three-dimensional objects |url=https://dl.acm.org/doi/10.1145/641675.642094 |journal=SIGARCH Comput. Archit. News |volume=3 |issue=4 |pages=23–27 |doi=10.1145/641675.642094 |issn=0163-5964}} It was extremely expensive, and very few units were ever sold.{{Cite thesis |last=Crow |first=Franklin C. |title=The aliasing problem in computer-synthesized shaded images. |date=1976 |degree=PhD |publisher=The University of Utah |url=https://apps.dtic.mil/sti/citations/ADA038979 |doi=}}
History
File:1967 512x512 Cube Rendering at Univ of Utah.png in 1967.]]
File:1970 Church Rendering by Watkins at Univ of Utah.png 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.{{Cite book |last1=Wylie |first1=Chris |last2=Romney |first2=Gordon |last3=Evans |first3=David |last4=Erdahl |first4=Alan |chapter=Half-tone perspective drawings by computer |date=1967-11-14 |title=Proceedings of the November 14-16, 1967, fall joint computer conference on - AFIPS '67 (Fall) |chapter-url=https://dl.acm.org/doi/10.1145/1465611.1465619 |location=New York, NY, USA |publisher=Association for Computing Machinery |pages=49–58 |doi=10.1145/1465611.1465619 |isbn=978-1-4503-7896-3}} 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".{{Cite thesis |last=Watkins |first=Gary Scott |title=A real time visible surface algorithm |date=1970 |degree=PhD |publisher=The University of Utah |url=https://bitsavers.org/pdf/univOfUtah/UTECH-CSc-70-101_Watkins_Dissertation_Jun70.pdf}} 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.
About a year earlier in 1972, Evans & Sutherland sold the first and only CT1 to Case Western Reserve University.{{Cite web |title=History of Evans & Sutherland Computer Corporation |publisher=FundingUniverse |url=https://www.fundinguniverse.com/company-histories/evans-sutherland-computer-corporation-history/ |access-date=2024-11-09}} 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,{{Cite journal |last=Christianson |first=David C. |date=1989-08-01 |title=History of visual systems in the Systems Engineering Simulator |url=https://ntrs.nasa.gov/citations/19900011365 |journal=Graphics Technology in Space Applications (GTSA 1989) |language=en}} 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. The Shaded Picture System, in contrast, was intentionally marketed.File:E&S Picture System and Frame Buffer.png 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.{{Citation |last1=Kajiya |first1=James T. |title=A random-access video frame buffer |date=1998-07-01 |work=Seminal graphics: pioneering efforts that shaped the field, Volume 1 |volume=1 |pages=315–320 |url=https://dl.acm.org/doi/10.1145/280811.281022 |access-date=2024-11-09 |place=New York, NY, USA |publisher=Association for Computing Machinery |doi=10.1145/280811.281022 |isbn=978-1-58113-052-2 |last2=Southerland |first2=Ivan E. |last3=Cheadle |first3=Edward C.|url-access=subscription }} 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.{{Cite book |url=http://www.bitsavers.org/magazines/Datamation/197512.pdf |title=Datamation |date=December 1975 |page=51}}
See also
References
{{Evans & Sutherland}}