ABSTRACT
In addition to the visually pleasing aspects of soft shadows, studies by Rademacher et al. [472] indicate that the presence of soft shadows contribute greatly to the realism of an image, which makes the generation of soft shadows that much more important. In this chapter, we only discuss soft shadows from extended light sources, such as linear lights, polygonal, spherical, and general area lights, and volumetric lights. Several excellent surveys [227, 7, 158] exist on this topic. Other sources of soft shadows are discussed in Chapter 5; they include motion blur (Section 5.7), ambient occlusion (Section 5.8), precomputed radiance transfer (Section 5.9), and global illumination (Section 5.10).
