ABSTRACT
We have so far covered the basic theoretical aspects of conics in the pro jective plane. Our definition was based on the concept of projectivities between lines or pencils — we will now use that concept for a more tan gible description. This will be the parametric form, which will allow us to trace curves, and also to calculate derivatives. We will spend some time on parametric conics, as they are important by themselves, but also since many of their properties will carry over very naturally to rational Bezier curves or to NURBS.
