OGRE实现天气昼夜变幻效果源码

-------------------------------------------------------------------------------- Copyright (C) 2009 Xavier Vergu�n Gonz�lez <xavierverguin@hotmail.com> <xavyiy@gmail.com> 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 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. 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