12.6. Further Information
Hemisphere lighting has been popularized by Microsoft and is described in several presentations on DirectX. An online article, Per-Pixel Lighting, by Microsoft's Phil Taylor describes this technique. Material in this article was derived from a talk given by Dan Baker and Chas Boyd at Meltdown 2001.
Image-based lighting builds on the foundations of texture mapping and reflection mapping first discussed by Jim Blinn and Martin Newell in 1976. Paul Debevec has recently popularized this area and maintains a Web site (http://www.debevec.org/) with lots of useful information on this topic, including a gallery of light probe images, the history of reflection mapping, electronic versions of his publications, and much more. A related Web site is http://www.hdrshop.com from which you can download the free (for personal and educational use) version of HDRShop or obtain the commercial version. There are also tutorials that helped me create the light probe images and environment maps described in this chapter.
Spherical harmonic lighting was described by Ravi Ramamoorthi and Pat Hanrahan in their 2001 SIGGRAPH paper. A lengthy and more tractable discussion of the details of this approach is available in a white paper by Robin Green of Sony.
The überlight shader for RenderMan is discussed in the book Advanced RenderMan: Creating CGI for Motion Pictures by Apodaca and Gritz. A Cg version of this shader is described by Fabio Pellacini and Kiril Vidimice in the book GPU Gems, edited by Randima Fernando.