Thomas Douglas Selkirk Duff (b. December 8, 1952, named for his putative ancestor, the fifth Earl of Selkirk) is a computer programmer. He was born in Toronto, Ontario, Canada and grew up in Toronto and Leaside. In 1974 he graduated from the University of Waterloo with a B.Math and, two years later, got an M.Sc. from the University of Toronto.

Career

Duff worked at the New York Institute of Technology Computer Graphics Lab and the Mark Williams Company in Chicago before moving to Lucasfilm's Computer Research and Development Division. He and Thomas Porter, another Lucasfilm employee, developed a new approach to compositing images; their 1984 paper, "Compositing Digital Images",^[1] is "[t]he seminal work on an algebra for image compositing", according to Keith Packard.^[2] and "Porter-Duff compositing" is now a key technique in computer graphics. (See, for example, XRender and Glitz.)

Duff later worked at Bell Labs Computing Science Research Center, where he authored the well known "rc" shell for the (Unix-like) Plan 9 operating system.

Duff has worked at Pixar Animation Studios since 1996.

Achievements

• In 1995 he was awarded (with others) the Academy Scientific and Engineering Award for his work on digital image compositing. With Bill Reeves he designed the first version of Pixar's Marionette 3-D animation system, which won the same award in 1997.

• While working at Lucasfilm, he created Duff's device, a loop-unrolling mechanism in C.

• On August 22, 2006, the United States Patent and Trademark Office issued U.S. Patent 7,095,409  to Pixar for a "Shot shading method and apparatus" invented by Tom Duff and Robert L. Cook

• On October 31, 2006, the United States Patent and Trademark Office issued U.S. Patent 7,129,940  to Pixar for a "Shot rendering method and apparatus" invented by Tom Duff and Robert L. Cook

Quotes

• "Shared libraries are the work of the devil, the one true sign that the apocalypse is at hand." [1]
• "Nobody really knows what the Bourne shell's grammar is. Even examination of the source code is little help." [2]

Miscellaneous

• Tom Duff makes a cameo appearance in the Niven/Pournelle science fiction novel Footfall as a co-discoverer of the invading spaceship: "Chap named Tom Duff, a computer type, spotted it."

See also

• Mothra - A web browser Tom Duff wrote for Plan 9.

External links

• Tom Duff (short cv on family web site)
• iq0 (personal web site)
• rc - The Plan 9 Shell
• A Quick Introduction to the Plan 9 Panel Library, a GUI toolkit by Tom Duff