The middle picture shows the public area in the Reichstag building where the presentation was situated. This is done using a wavelet transform of the spline data, which has a number of advantages to other hierarchical representations. It also allows for easy implementation of direct manipulation, i.e. dragging the curve directly instead of fuddling with control points. The pictures below show the effect of editing a spline curve with a virtual control polygon of lower resolution. I took up an old project I did at school and ported it to Win95.
Some figures explaining the tesselation are available.
The picture of a hand to the left features a negative sphere to form the palm. This and the following pictures show the effect of grabbing one sphere and pulling it away from the others. Still in touch, but the bond gets smaller. The field between the spheres finally drops below the surface threshold. Another project from school dealt with IK on articulated structures.