A topic in current mathematical research deals with the investigation of socalled ''circle packings'', i.e. packings of (empty) circles which touch each other in a certain way. Together with an appropriate colouring certain types of circle packings trigger human depth perception,
For instructions about how the JAVA Applet Kreistiefe works, please see Instructions.
The mathematical background of kreistiefe can be read in an online paper by A. I. Bobenko and T. Hoffmann with the title: ''Conformally symmetric Circle Packings: A Generalization of Doyle Spirals'' at http://www-sfb288.math.tu-berlin.de/Publications/online/.