4SHADOWS AND REFLECTIONS
Our quest to render the scene in progressively more realistic ways continues. In the previous chapter, we modeled the way rays of light interact with surfaces. In this chapter, we’ll model two aspects of the way light interacts with the scene: objects casting shadows and objects reflecting on other objects.
Where there are lights and objects, there are shadows. We have lights and objects. So where are our shadows?
Let’s begin with a more fundamental question. Why should there be shadows? Shadows happen when there’s a light whose rays can’t reach an object because there’s some other object ...