This chapter discusses the use of textures for representing surface detail, shadows, and reflections. The use of texture mapping and animation together readily produces truly dramatic aliasing, and much of the complexity of texture mapping systems is created by the antialiasing measures that are used to tame the artifacts. Designing the texture coordinate function well is a key requirement for getting good results with texture mapping. Geometrically determined texture coordinates are used for simple shapes or special situations, as a quick solution, or as a starting point for designing a hand-tweaked texture coordinate map. Surfaces that are roughly spherical in shape can be parameterized using a texture coordinate function that maps a point on the surface to a point on a sphere using radial projection: take a line from the center of the sphere through the point on the surface, and find the intersection with the sph.