T-Square (software)

Students of Jack Dennis and John McCarthy discovered a stunning array of uses for the very expensive room-sized computers that were given to MIT. They were privileged to be enrolled when the school's first programming courses were taught.

They negotiated with their advisors and the operations manager John McKenzie for time and became single-users long before personal computers were available. About 1959 or 1960, some of this group of students became support staff and wrote software for about $1.75 USD per hour.{{cite web

|title = The Inflation Calculator

|author = About $11.09 in 2005 USD

|date = 11 December 2000

|url = http://www.westegg.com/inflation/

|accessdate = 2006-12-30

|url-status = dead

|archiveurl = https://web.archive.org/web/20110718031608/http://www.westegg.com/inflation/

|archivedate = 2011-07-18

}} They wrote the programming software which is used to build application software. Later Samson and Kotok became architects of DEC computers.

During this period Samson created other "firsts" in application software for music, games and page layout so it is perhaps not surprising he wrote what may be the first drafting program. Based on this experience, later in life Samson worked on an electronic drafting program with 80,000 lines of code. He received a patent{{cite web

| title= Optical convergence accommodation assembly, US Patent 5,557,459

| author=Samson; Peter R., inventor, Autodesk, Inc., assignee

| date=1994-10-27

| url=http://patft.uspto.gov/netacgi/nph-Parser?Sect1=PTO1&Sect2=HITOFF&d=PALL&p=1&u=%2Fnetahtml%2FPTO%2Fsrchnum.htm&r=1&f=G&l=50&s1=5,557,459

| accessdate=2006-12-27

}} in virtual reality at Autodesk, a vendor of CAD and CAM software.

To move the cursor, T-Square used a Spacewar! game controller built by Kotok and Saunders in 1962. It is not known if Saunders was involved in repurposing it for T-Square. Kotok, who was about 20 years old, did participate. He was known for doing what needed to be done and for taking an interest in "all things ingenious or intriguing."{{cite web

| last=Wright | first=Sarah H., quoting Tim Berners-Lee

| title=Alan Kotok, 64, created joystick

| publisher=MIT News Office

| date=13 June 2006

| url=http://web.mit.edu/newsoffice/2006/obit-kotok.html

| accessdate=2006-12-27

}}

The Spacewar! [http://www.atarimagazines.com/cva/v1n1/spacewar4.jpg control boxes] were cobbled together with wood, Bakelite and toggle switches. Although they are often considered to be the first joysticks, Kotok did not accept credit for coinventing them with Saunders.{{cite web

| last=Haas | first=Hugo

| title=Goodbye, Alan

| publisher=W3C public-memoria@w3.org archive

| date=4 June 2006

| url=http://lists.w3.org/Archives/Public/public-memoria/2006Jun/0017.html

| accessdate=2006-12-27

}}

Image:ARISTO-GEO DREIECK 1550 indiziert transparent.svg used in drafting by hand. Illustration by Richard Schneider]]

T-Square is a small part of the reason people use today's computers for drafting, architecture, drawing and illustration and engineering. Prior to this revolution and in some places to this day, draftsmen and women used triangles, wood or metal T-squares, pencils and technical pens on film and paper. The beginning of this change can be seen in a video of Sutherland demonstrating Sketchpad.{{cite web

| title=Alan Kay: Doing with Images Makes Symbols Pt 1

| author=University Video Communications (sponsored by the Higher Education Marketing Group, Apple Computer, Inc. Copy courtesy Internet Archive.)

| year=1987

| url=https://archive.org/details/AlanKeyD1987

| accessdate=2006-12-27

}}

:* See also [https://archive.org/movies/thumbnails.php?identifier=AlanKeyD1987 thumbnails]

In his 1963 MIT Ph.D. thesis, Sutherland explains he completed an early version that could draw parallel and perpendicular lines in November 1961. He goes on to say, "Somewhat before my first effort was working, Welden Clark of Bolt, Beranek and Newman..." showed him a "similar program" running on a PDP-1.{{cite journal | last=Sutherland | first=Ivan Edward | title=Sketchpad: A man-machine graphical communication system (courtesy Computer Laboratory, University of Cambridge UCAM-CL-TR-574 September 2003) | publisher=Massachusetts Institute of Technology | date= January 1963 | doi=10.48456/tr-574 | url=http://www.cl.cam.ac.uk/techreports/UCAM-CL-TR-574.html | accessdate=2006-12-26}} T-Square and Sketchpad were developed in the same location a year or two apart but their influence on each other is unknown.

• Sketchpad
• T-square

{{Reflist}}

• {{cite web

| author=Computer History Museum

| title=The Mouse that Roared: PDP-1 Celebration Event (Running Time: 01:53:46)

| date= 15 May 2006

| url=http://www.computerhistory.org/pdp-1/index.php?f=showitem&id=25.26&popupwin=1

| accessdate=2006-12-28

}}

:*Also available at Google Video: {{cite web

| author=Computer History Museum

| title=The Mouse that Roared: PDP-1 Celebration Event (Running Time: 01:53:46)

| date= 15 May 2006

| url=http://video.google.com/videoplay?docid=4995476926708958999&q=computer+history+dec

| accessdate=2006-12-28

}}

• {{cite web

| author=Computer History Museum

| title=PDP-1 Restoration Project: Applications

| year=n.d.

| url=http://www.computerhistory.org/pdp-1/index.php?f=theme&s=4

| accessdate=2006-12-28

}}

Category:Computer-aided design software

Category:Technical drawing

Category:History of software