Licence Addendum: Additional Terms (Patents)

This addendum accompanies the Creative Commons Attribution-NonCommercial-
ShareAlike 4.0 International licence (the "Licence", see the LICENSE file)
under which Ubicoders makes the VRobots SDK available. It is offered by
Ubicoders as Licensor, in addition to the Licence, and forms part of the terms
on which the SDK is licensed. It does not alter the text of the Licence. Terms
written with a capital letter have the meaning the Licence gives them.

"This implementation" means the copyrightable works distributed by Ubicoders
as part of the VRobots SDK: the SDK libraries, bindings and tools, the example
programs and the VRobots Book. "Covered Work" means this implementation and
any Adapted Material based on it, in whole or in part.

1. Patent licence from Ubicoders

   Ubicoders grants to You a perpetual, worldwide, non-exclusive, no-charge,
   royalty-free, irrevocable (except as stated in section 4) patent licence to
   make, have made, use, run, modify and propagate this implementation, but
   only to the extent that You do so within the rights granted to You by the
   Licence (in particular, for NonCommercial purposes as the Licence defines
   them). This licence covers only those patent claims, owned or controlled by
   Ubicoders now or in the future, that are necessarily infringed by this
   implementation. It does not cover claims that would be infringed only as a
   consequence of further modification of this implementation.

2. No patents on the Covered Work

   As a condition of the Licence, You agree not to file, prosecute, acquire or
   maintain any patent application or patent, anywhere in the world, that
   claims any part of the Covered Work, any method that the Covered Work
   performs, or any Adapted Material You or anyone else creates from it. This
   includes claims dressed as improvements, combinations or applications of
   the Covered Work.

3. Grant-back of any such patent

   If, despite section 2, You or Your agent, affiliate or exclusive licensee
   own or control a patent claim that reads on the Covered Work or on any
   Adapted Material, that claim is hereby licensed, perpetually, worldwide,
   royalty-free and irrevocably, to Ubicoders and to every person who receives
   the Covered Work under the Licence, for everything the Licence permits.
   This grant-back survives any termination of Your rights.

4. Termination

   Your rights under the Licence and under section 1 terminate automatically
   on the date You, or anyone acting for You, (a) file a patent application
   in breach of section 2, or (b) institute, order or agree to the
   institution of patent litigation or any other patent enforcement activity
   against any entity (including a cross-claim or counterclaim) alleging that
   the Covered Work, or any code incorporated within it, constitutes direct or
   contributory patent infringement, or inducement of patent infringement.
   Sections 3 and 5 survive termination.

5. Scope

   Nothing in these terms permits Commercial use of the Covered Work. Nothing
   in these terms limits any right Ubicoders has under the Licence, under
   copyright or under patent law. These terms bind everyone who exercises the
   Licensed Rights; a person who does not accept them has no rights under the
   Licence.
