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Real-Time Nonphotorealistic Rendering
Author(s): Lee Markosian, Michael A. Kowalski, Samuel J. Trychin, Lubomir D. Bourdev, Daniel Goldstein, John F. Hughes.
Proceedings: ACM Siggraph 97, Annual Conference Series 1997, pp. 415--420, August,
1997.
[BibTeX] 
Abstract:
Nonphotorealistic rendering (NPR) can help make comprehensible but simple pictures of complicated objects by employing an economy of line. But current nonphotorealistic rendering is primarily a batch process. This paper presents a real-time nonphotorealistic renderer that deliberately trades accuracy and detail for speed. Our renderer uses a method for determining visible lines and surfaces which is a modification of Appel’s hidden-line algorithm, with improvements which are based on the topology of singular maps of
a surface into the plane. The method we describe for determining visibility has the potential to be used in any NPR system that requires a description of visible lines or surfaces in the scene. The major contribution of this paper is thus to describe a tool which can significantly improve the performance of these systems. We demonstrate the systemwith several nonphotorealistic rendering styles, all of which operate on complex models at interactive frame rates.