/*
Author: Geraint Luff and others
Year: 2013

This code is released into the "public domain" by its author(s).  Anybody may use, alter and distribute the code without restriction.  The author makes no guarantees, and takes no liability of any kind for use of this code.

If you find a bug or make an improvement, it would be courteous to let the author know, but it is not compulsory.
*/