The convex hull of ellipsoids

The treatment of curved algebraic surfaces becomes more and more the f ocus of attention in Computational Geometry. We present a video that illustrates the computation of the convex hull of a set of ellipsoids. The underlying algorithm is an application of our work on determining a cell in a 3-dimensional arrangement of quadrics, see \cite{ghs-ccaq-01}. In the video, the main emphasis is on a simple and comprehensible visualization of the geometric aspects of the algorithm. In addition, we give some insights into the underlying mathematical problems.