License of source code GNU Lesser General Public License, version 2.1 Copyright (C) 2017 Karamel With knowledge from various Minetest developers, modders and documenters This program is free software; you can redistribute it and/or modify it under the terms of the GNU Lesser General Public License as published by the Free Software Foundation; either version 2.1 of the License, or (at your option) any later version. This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more details: https://www.gnu.org/licenses/old-licenses/lgpl-2.1.html