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Stylized Highlights for Cartoon Rendering and Animation
July/August 2003 (vol. 23 no. 4)
pp. 54-61
Ken-ichi Anjyo, OLM Digital
Katsuaki Hiramitsu, OLM Digital

A novel highlight shader depicts cartoon-style highlights for 3D objects in cel animation. In general, highlighting in cel animation is used semantically, rather than photorealistically, by employing simple primitives-such as white stripes on a window or crescent figures on an alloy wheel. It's difficult and tedious work, however, to get such a stylized highlight animation for 3D models when using conventional cartoon-shading algorithms.

This article presents an approach that generalizes the concept of a highlight for 3D objects in cel animation. This is achieved by introducing a new class of vector field-called a highlight vector field-on a surface to be depicted. A generalized highlight area on the surface is then defined through the highlight vector field. Thus, this highlight shader enables cartoon-style highlighting through simple operations defined for the highlight vector field. These operations actually correspond to the direct manipulations on the highlight area defined by the vector field, these include local affine transform and simple deformation of the highlight.

1. B.-T. Phong, "Illumination for Computer Generated Pictures," Comm. ACM, vol. 18, no. 6, 1975, pp. 311-317.
2. J.F. Blinn, "Models of Light Reflection for Computer Synthesized Pictures," Computer Graphics, vol. 11, no. 2, 1977, pp. 192-198.
1. K. Anjyo et al., "Digital Cel Animation in Japan," Siggraph 2000 Conf. Abstracts and Applications, ACM Press, 2000, pp. 115-117.
2. M. Arias, "Non-Photorealistic Rendering," Softimage|XSI Power Creators' Guide, Aspects Corp., 2002, pp. 284-290.
3. W. Corrêa et al., "Texture Mapping for Cel Animation," Proc. Siggraph 98, ACM Press, 1998, pp. 435-446.
4. P. Rademacher, "View-Dependent Geometry," Proc. Siggraph 99, ACM Press, 1999, pp. 439-446.
5. L. Petrovic et al., "Shadows for Cel Animation," Proc. Siggraph 2000, ACM Press, 2000, pp. 511-516.
6. A. Lake et al., "Stylized Rendering Techniques For Scalable Real-Time 3D Animation," Proc. 1st Int'l Symp. Non-Photorealistic Rendering (NPAR 00), ACM Press, 2000, pp. 13-20.

Ken-ichi Anjyo, Katsuaki Hiramitsu, "Stylized Highlights for Cartoon Rendering and Animation," IEEE Computer Graphics and Applications, vol. 23, no. 4, pp. 54-61, July-Aug. 2003, doi:10.1109/MCG.2003.1210865
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