Graphics Facilities at Ames Research Center
Graphics equipment and device-independent software at NASA Ames
McConnell, J., "Graphics Facilities at Ames Research Center", RFC 126, DOI 10.17487/RFC0126, April 1971, <https://www.rfc-editor.org/info/rfc126>.
@misc{rfc126,
series = {Request for Comments},
number = 126,
howpublished = {RFC 126},
publisher = {RFC Editor},
doi = {10.17487/RFC0126},
url = {https://www.rfc-editor.org/info/rfc126},
author = {J. McConnell},
title = {{Graphics Facilities at Ames Research Center}},
pagetotal = 1,
year = 1971,
month = apr,
} RFC text
Network Working Group John McConnell
Request for Comments: 126 Ames Research Center
Category: D.6 April 1971
Ames Graphics Facilities at Ames Research Center
This note is intended as a response to an RFC which suggested that
nodes describe their graphics environment. The following graphics
facilites are now at Ames for the IBM 360/67 TSS:
a. An SC 4020 off line microfilm system.
b. Calcomp plotters.
c. ARDS storage tube CRTs.
d. IMLAC PDS-1 refresh CRTs.
e. One IBM 2250 CRT.
Devices which will be in use in the near future are:
a. An Evans and Sutherland LDS-2 system.
b. Hazeltine alphanumeric CRTs.
Because of the diverse nature of the devices and the varying software
support provided by the manafacturers, work has been undertaken to
provide a device independent package. This package is currently being
implemented. The basic entity is a device independent intermediate
language which describes the picture to be displayed. When a device
is selected, the intermediate language is converted to specific
device orders.
Other features include the definition and storage of subpictures for
later construction of more complex pictures. An interface has been
specified so that graphic data sets can be transmitted to other
installations on the TSS network.
A note to those who plan to use the ILLIAC IV when it becomes a
functioning node at Ames. I would like information concerning the
graphics environment at your sites and any thoughts you have on how
you will be using graphics with the ILLIAC IV.
[ This RFC was put into machine readable form for entry ]
[ into the online RFC archives by Andrew Crawford 4/97 ]
AI ELI5
On this page
§1Graphics Hardware at Ames
As of 1971, NASA Ames Research Center for the IBM 360/67 TSS system had five graphics devices: an SC 4020 off-line microfilm system, Calcomp plotters, ARDS storage-tube CRTs, IMLAC PDS-1 refresh CRTs, and one IBM 2250 CRT. Additional devices were planned, including an Evans and Sutherland LDS-2 system and Hazeltine alphanumeric CRTs.
This diverse collection presented a software engineering challenge: each device had different capabilities and expected different command formats.
The lab had many different drawing machines: some that printed on paper, some that drew on film, some that showed pictures on screens. Each one spoke its own language.
§2Device-Independent Graphics
Rather than writing separate code for each device, Ames developed a device-independent graphics package. The core uses a device-independent intermediate language that describes a picture in abstract terms, without reference to any specific hardware. When a device is selected, a conversion step translates the intermediate language into the specific commands that device understands.
The package also provides features for defining and storing subpictures, which can be reused in constructing more complex pictures. Graphics data sets can be transmitted across the TSS network to other installations, allowing shared work on graphics.
Instead of writing a different program for each machine, they write one program that describes pictures in a universal language. Another program translates that language to whatever machine is being used.
§3Network Graphics and Scaling
RFC 126 notes that ILLIAC IV would become a functioning node at Ames in the future, and the author asks other sites to describe their graphics environments and their plans for using graphics with ILLIAC IV. This indicates that graphics capabilities were expected to be shared and used across the network.
As the network grows, different laboratories will want to share their graphics work. The device-independent approach makes that possible.