Computer Graphics from Scratch

11CLIPPING

In the last few chapters, we developed equations and algorithms to transform a 3D definition of a scene into 2D shapes we can draw on the canvas; we developed a scene structure that lets us define 3D models and place instances of those models in the scene; and we developed an algorithm that lets us render the scene from any point of view.

However, doing this exposes one of the limitations we’ve been working with: the perspective projection equations only work as expected for points that are in front of the camera. Since we can now move and rotate the camera around the scene, this poses a problem.

In this chapter, we’ll develop the techniques ...