Tom Duff

Tom Duff, born Thomas Douglas Selkirk Duff on 8 December 1952, is a Canadian computer programmer who spent his career in computer graphics and Unix systems work. Born and raised in Toronto, he studied mathematics at the University of Waterloo and took a master's degree at the University of Toronto before working at the New York Institute of Technology Computer Graphics Lab, the Mark Williams Company and Lucasfilm. With Thomas Porter he developed Porter-Duff compositing, an algebra for combining digital images that remains a key technique in computer graphics. In 1983 he devised Duff's device, a loop unrolling construction in C, and during twelve years at Bell Labs he wrote the rc shell for Version 10 Unix. He worked at Pixar Animation Studios from 1996 until retiring in 2021 and shared two Academy scientific and engineering awards.