Photon is licensed under a zlib license, the full license is below.
------------

Copyright (c) 2005 James Turk

This software is provided 'as-is', without any express or implied warranty. In 
no event will the authors be held liable for any damages arising from the use 
of this software.

Permission is granted to anyone to use this software for any purpose, including
commercial applications, and to alter it and redistribute it freely, subject to
the following restrictions:

    1. The origin of this software must not be misrepresented; you must not 
    claim that you wrote the original software. If you use this software in a 
    product, an acknowledgment in the product documentation would be 
    appreciated but is not required.

    2. Altered source versions must be plainly marked as such, and must not 
    be misrepresented as being the original software.

    3. This notice may not be removed or altered from any source distribution.

$Id: LICENSE.txt,v 1.1 2005/07/17 22:41:03 cozman Exp $
