 My advisor is  <a href="http://www.cs.washington.edu:80/homes/salesin/">David Salesin</a>. He came to our department in 1992 with a whole bunch of cool ideas for graphics research.  One of those was non-photorealistic rendering, specifically pen-and-ink illustration.  Our graphics group worked on two projects in this area.  One was the  <a href="http://www.cs.washington.edu/research/projects/grail2/www/projects/cg-illus/"> automatic generation of pen-and-ink illustrations</a> given three-dimensional models and some  texture information.  The other one, the one I worked on, addressed the <a href="http://www.cs.washington.edu/research/projects/grail2/www/projects/int-illus/"> interactive creation of pen-and-ink illustrations</a> given a  two-dimensional grayscale starting image.   <p>
