Copyright (c) 2011
   Pavel Batanov <pavel@batanov.me>
   Sergey Batanov <dmpas@dmpas.ru>

   Ray Tracing Software.

   Ray Tracing Software. is free software: you can redistribute it
   and/or modify it under the terms of the Attribution-ShareAlike 3.0
   Unported (CC BY-SA 3.0) license.

   for Attribution-ShareAlike 3.0 Unported (CC BY-SA 3.0) license
   see http://creativecommons.org/licenses/by-sa/3.0/deed.en
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