.
A Developer's Guide to Silhouette Algorithms for Polygonal Models
Tobias Isenberg, Bert Freudenberg, Nick Halper, Stefan Schlechtweg, Thomas Strothotte.
IEEE Computer Graphics and Applications, Vol. 23, No. 4, pp. 28--37, July/August,
2003. [BibTeX]
Game Programming Gems 4
Bert Freudenberg, Maic Masuch, Thomas Strothotte.
Andrew Kirmse, Real-Time Halftoning: Fast and Simple Stylized Shading, pp. 443--440, Charles River Media,
2004. [BibTeX]
Non-Photorealistic Shading in an Educational Game Engine
Bert Freudenberg, Maic Masuch.
Production Process of 3D Computer Graphics Applications - Structures, Roles and Tools, Snowbird, Utah, USA, June 1 - 4,
2002. [BibTeX]
OPENNPAR: A System for Developing, Programming, and Designing Non-Photorealistic Animation and Rendering
Author(s): Nick Halper, Tobias Isenberg, Felix Ritter, Bert Freudenberg, Oscar E. Meruvia Pastor, Stefan Schlechtweg, Thomas Strothotte.
Proceedings: 11th Pacific Conference on Computer Graphics and Applications (PG'03), pp. 424, Canmore, Canada,
2003.
[BibTeX] 
Abstract:
The notable amount and variation of current techniques in non-photorealistic rendering (NPR) indicates a level of maturity whereby the categorization of algorithms has become possible. We present a conceptual model for NPR, on which we base a modular system, OPENNPAR, which integrates NPR algorithms into distinct classes. Components in OPENNPAR are modularized and consequently reintegrated for various rendering purposes, allowing many kinds of NPR algorithms to be reproduced, including the integration of 2D and 3D methods. Additionally, the system provides support for a range of users (developers, programmers, designers) according to their respective levels of abstraction, thus being available in multiple contexts. Ultimately, OPENNPAR holds great potential as a tool in the development, augmentation, and creation of NPR effects.
Real-Time Animated Stippling
Oscar E. Meruvia Pastor, Bert Freudenberg, Thomas Strothotte.
IEEE Computer Graphics and Applications, Vol. 23, No. 4, pp. 62-68,
2003. [BibTeX]
Real-Time Halftoning: A Primitive For Non-Photorealistic Shading
Bert Freudenberg, Maic Masuch, Thomas Strothotte.
Eurographics Workshop on Rendering, pp. 1–4,
2002. [BibTeX]
Real-Time Stroke Textures
Bert Freudenberg.
Technical Sketch presented at SIGGRAPH 2001,
2001. [BibTeX]
Real-Time Stroke-Based Halftoning
Bert Freudenberg.
Otto-von-Guericke-Universität, Magdeburg,
2003. [BibTeX]
Subdivision for Line Drawings
Bert Freudenberg.
2001. [BibTeX]
The Computer-Visualistik-Raum: veritable and inexpensive presentation of a virtual reconstruction
Bert Freudenberg, Maic Masuch, Niklas Röber, Thomas Strothotte.
Proceedings of the 2001 conference on Virtual reality, archeology, and cultural heritage (VAST '01), pp. 97--102,
2001. [BibTeX]