This demonstration project, aside from the Yukkuri Games logo, is
released into the public domain.

The person who associated a work with this deed has dedicated the work
to the public domain by waiving all of his or her rights to the work
worldwide under copyright law, including all related and neighboring
rights, to the extent allowed by law.

You can copy, modify, distribute and perform the work, even for
commercial purposes, all without asking permission.

See https://creativecommons.org/publicdomain/zero/1.0/ for details.

The source code under src/yuu remains under the terms of the GNU GPL
versions 2 or later, unless specified otherwise in the files.