Gary Bishop
ABSTRACT
Computer image generation systems often represent curved surfaces as a mesh of planar polygons that are shaded to restore a smooth appearance. Phong shading is a well known algorithm for producing a realistic shading but it has not been used by real-time systems because of the 3 additions, 1 division, and 1 square-root required per pixel for its evaluation. We describe a new formulation for Phong shading that reduces the amount of computation per pixel to only 2 additions for simple Lambertian reflection and 5 additions and 1 memory reference for Phong's complete reflection model. We also show how to extend our method to compute the specular component with the eye at a finite distance from the scene rather than at infinity as is usually assumed. The method can be implemented in hardware for real-time applications or in software to speed image generation for almost any system.
- Duff, T. 1979. "Smoothly Shaded Renderings of Polyhedral Objects on Raster Displays," ACM Computer Graphics, vol. 13, no. 2, pp. 270-275. Google Scholar
Digital Library
- Foley, J. D. and A. Van Darn. 1983. Fundamentals of Interactive Computer Graphics, Addison Wesley, Reading, MA. Google ScholarDigital Library
- Gouraud, H. June 1971. "Continuous Shading of Curved Surfaces," IEEE Transactions on Computers, vol. 20, no. 6, pp. 623-628.Google ScholarDigital Library
- Newman, W. N. and R. F. Sproull. 1979. Principles of Interactive Computer Graphics, McGraw-Hill, New York, NY. Google ScholarDigital Library
- Phong, B. T. July 1973. Illumination for Computer- Generated Images, Ph.D. Dissertation, Department of Computer Science, University of Utah, Salt Lake City. Gov. ordering no. AD-A008 786. Google ScholarDigital Library
- Whitted, T. and D. Weimer. 1982. "A Software Testbed for the Development of 3D Raster Graphics Systems,~' ACM Transactions on Graphics, vol. 1, no. 1, pp. 43-58. Google ScholarDigital Library
Index Terms
Fast Phong shading
Recommendations
Fast Phong shading
Computer image generation systems often represent curved surfaces as a mesh of planar polygons that are shaded to restore a smooth appearance. Phong shading is a well known algorithm for producing a realistic shading but it has not been used by real-...
Situation normal [Gourand and Phong shading]
Two of the most famous graphics techniques, derived from shading algorithms by Henri Gouraud and Bui Tuong Phong, have been implemented in hardware and software worldwide. Both methods use various hacks to smooth out the shading of a polygonal surface. ...
Comments