OpenGL® Shading Language, Third Edition

Chapter 14. Surface Characteristics

Up to this point, we have primarily been modeling surface reflection in a simplistic way. The traditional reflection model is simple enough to compute and gives reasonable results, but it reproduces the appearance of only a small number of materials. In the real world, there is enormous variety in the way objects interact with light. To simulate the interaction of light with materials such as water, metals, metallic car paints, CDs, human skin, butterfly wings, and peacock feathers, we need to go beyond the basics.

One way to achieve greater degrees of realism in modeling the interaction between light and surfaces is to use models that are more firmly based on the physics of light reflection, absorption, and ...