Neil McKay works in the Manufacturing Systems Research lab [L1 ] at General Motors Research and Development. He also has taught computer graphics at the University of Michigan [L2 ] in Ann Arbor. His web page is:
http://www.eecs.umich.edu/~mckay
The computer section of the web page has a number of Tcl/Tk extensions available for download, including:
Neil is also the author of Tk3D, which his employer has very graciously allowed him to release as open source code.
Also known as NDM.