“A unified framework for 3D non-photorealistic rendering” by Kim, Kim, Kim and Koo

The field of Non-Photorealistic Rendering(NPR) has leaped forward as a variety of techniques to create artistic expression are  proposed. Unfortunately, the aim of most methods is generally  to express a specific one of artistic styles. A few approaches including [Grabli et al. 2004] and [Halper et al. 2003] have been  proposed to provide an appropriate environment to develop various new styles. However, they didn’t provide sufficient methods to  express inner lines like hatching and cross hatching lines. In this paper, we propose a unified framework for 3D NPR. Our framework was intended not to make a distinction between line  shading and cel shading. As a result, we could generalize various artistic styles with a simple conceptual framework and system  architecture.  

1. Grabli, S., Durand, F., Turguin, E., and Sillion, F. X. 2004. Programmable style for npr line drawing. In Proceedings of the Eurographics Symposium on Rendering, 33–44.
2. Halper, N., Isenberg, T., Ritter, F., Freudenberg, B., Meruvia, O., Schlechtweg, S., and Strothotte, T. 2003. Opennpar: A system for developing, programming, and designing non-photorealistic animation and rendering. In Proceedings of the 11th Pachific Conference on Compute Graphics and Application, 424–428.