the polygon edges blend together to produce a smooth look. Gourad shading produces
smooth renders but takes longer to complete than flat shading. Even more
complicated rendering techniques exist, such as ray tracing, radiosity and volume
rendering. We shall look into some of these techniques in Chapter 9, when we
explore advanced concepts. All techniques a trade-off between computation time
and intricacy of the final render. In the last few sections, we saw how to assign
material colors to models and then render them with a desired shading scheme. As
detail becomes finer and more intricate, explicit modeling becomes less practical.
An alternative method often used is to superimpose a completely independent
image (either digitized or programmatically generated) over the surface of the
object. This method is called texture mapping.