First the applet gets an initial point-set due to the entered number of vertices and the choosen construction method.
For optimization, select how to evaluate the given point set and press "poly" or "type".
The number above a point-set is its evaluation value, the data below is the Euler-vector of its combinatorial type.

In the first case, the applet only optimizes the point-set and leaves the combinatorial type untouched.

In the second case, the applet also tries to find the best combinatorial type of the point-set for given N.

It first optimizes the point-set according to the given combinatorial type.

Then one edge is flipped and the point-set is optimized using the new combinatorial type.
If we obtain a better point-set, we keep the point-set (and remove it otherwise).

The edge-flip stops if it flipped all edges of a point-set without getting a better point-set.

The button "Delaunay" stops the optimization and calculates the delaunay-triangulation of the point set.