Gregg M. Townsend

An American computer programmer, Townsend worked at the University of Arizona for a total of 36 years, retiring in 2009, but continued to work there on a part-time basis. He received his Bachelor's degree in 1974, during which time he worked at the University of Arizona Computer Center as a CDC systems programmer on the CDC 6400. After graduation he went to work for Control Data in Sunnyvale, AZ, working on the Loader project and then in the Systems Design Group. In 1977, he returned to the University of Arizona as a systems programmer working again on the 6400, which then became a Cyber 175.

He received his M.S. degree in 1984 from the University of Arizona, after which he joined the University's Department of Computer Science. As a graduate student he became involved with the Icon project under the direction of Ralph Griswold. His focus was on software tools, programming languages, code generation, virtual machines, optimization, image processing, watermarking, compression, cryptography, calligraphy, cartography, recreational mathematics, heuristics, visualization, and music. Townsend designed and built software packages and worked almost exclusively on Unix systems. He also worked extensively with the IBM 1401, CDC 6600, PDP-10, Poly-88, and Arduino.

Software programs which he developed or had a part in developing include: The Icon programming language; Jcon, a Java implementation of Icon; The SR programming language; The MPD programming language; dlgvu, a USGS topo map viewer; tgrmap, a TIGER map viewer; TopoVista, an interactive terrain viewer; sdts2dem, a translator for SDTS DEM files; Algorithm animation: bin packing; and Algorithm animation: traveling salesman. He was also involved with developing The Arizona Webcam, and The Illinois Zephyr, a CDC-compatible CPU designed and built by the University of Illinois in 1988 to run server software of the PLATO system.

He was a co-editor of The Icon Analyst and The Icon Newsletter from 1996 to 2001. Townsend was a co-author of Graphics Programming in Icon, with Ralph E. Griswold and Clinton L. Jeffery, 520 pages, 8 pages of color plates, multi-platform CD-ROM, Peer-to-Peer Communications, 1998, ISBN 1-57398-009-9.

Among the many other publications which he authored or co-authored are: A New Implementation of the Icon Language, with Todd A. Proebsting — Software — Practice and Experience 30, 8 (10 July 2000), 925–972 (a pdf file); in 1998 with Todd A. Proebsting, Jcon: A Java-Based Implementation of Icon, Icon Project Document 286 (available in html & pdf), Department of Computer Science; with William G. Griswold, The Design and Implementation of Dynamic Hashing for Sets and Tables in Icon, Software — Practice and Experience 23, 4 (April, 1993), 351–367 (a pdf file); with Clinton L. Jeffery and Ralph E. Griswold, Adding Graphics to a High-Level Programming Language, Software — Practice and Experience 25, 6 (June, 1995), 637–655 (a pdf file); and with Ralph E. Griswold, The Visualization of Dynamic Memory Management in the Icon Programming Language, Tech Report 89-30 (a pdf file), Department of Computer Science, 1989.

Townsend was a member of the Association of Computing Machines (ACM) and IEEE and supported the Electronic Frontier Foundation (EFF).