Ogre Forums

When I finish up my current job and move on to some other things, I'll be able to resume work on my 3D planet / galaxy engine. Edit: BTW, this has no effect on me releasing my Ogre planet rendering code, which I plan to release under zlib license soon.

I would like to make this engine which would otherwise be privately developed open-source so others can contribute if they like and use it in their projects, but in a somewhat unusual way: I would like to be able to offer versions of it under alternate licenses at any time, and I'm not sure how this would work with multiple contributers. Since I expect to be doing most of the work myself, it seems the best way to do this would be to somehow ensure that the copyrights are exclusively held by myself which of course would give me the right to change the licensing however I like, but I don't know how this would work with multiple contributers.

Does the copyright inherently remain in the hands of whoever is originally stated as the copyright holder, or is a contract needed for contributors to surrender their ownership of their work to the project owner? If it's too complicated and involves contracts, etc. then I probably won't bother. Basically I just want to allow people to contribute if they like and freely use the project under the chosen license. Initially, the license will most likely be a restrictive one like GPL which requires software using it be free/open-source, but I want to be able to offer unrestricted commercial licenses upon request - potentially with a fee depending on how professional the engine becomes, and after a number of years (if successful) maybe release it fully for free under something like zlib.

I know reserving the rights to a project and to potential commercialization of it's derivatives isn't exactly the open-source philosophy, but I like the idea of a GPL project like this where people can contribute and use it in free games, etc. - with possibilities for commercial licensing sales still open as a possibility, kind of like Ogre's alternate license.

I would look at how Intel phrases their dual licensed Thread Building Blocks (although there probably are no non-Intel-employee contributors there). You could also look at Sinbad's Contributor Agreement for hints as well.

JohnJ wrote:I know reserving the rights to a project and to potential commercialization of it's derivatives isn't exactly the open-source philosophy

It is.
You - and only you - hold the copyright. And you are free to do whatever you want with the library.
If you didn't, you wouldn't be able to offer commercial licenses.
You only need a contributor contract which transfer copyright of contributions to you, or the entity holding the copyright.

That's what I was afraid of. A contract would work I guess, but I really didn't want to complicate things this much. I guess the only way to be legally valid I'd have to mail/fax/email the contract to contributors and have them physically sign and return it?

Take a look at the Ogre contributor agreement.

jacmoe wrote:You only need a contributor contract which transfer copyright of contributions to you, or the entity holding the copyright.

Be careful with the wording of such a contract. In Germany, for example, you cannot transfer the copyright (except by inheritance), but you can grant an exclusive licence (see http://en.wikipedia.org/wiki/German_cop ... t_transfer)

Yeah, that's why I'm no lawyer . The Ogre Contributor License Agreement looks really good because it seems to work in this case too - it's just a signed license permitting you to rights including sublicensing, which is what I want.

Also, if I'm gonna use the Ogre Contributor License Agreement, I don't see any copyright on the document itself, but I guess I should ask sinbad anyway before I use it for my purpose.

You should take a look at the Free Software Foundation Europe's Fiduciary Licence Agreement. It's designed pretty much for this sort of thing and is now being used by KDE for the transferal of copyright.

But is there any advantage to using that over the Ogre license agreement? Both require signatures.

Feel free to use bits of ours as you see fit. I think it's fairly representative of the approach many modern open source projects take, ie not doing a unilateral copyright assignment, allowing both parties to do as they wish with the contributed code.

In our case we used to just ask for permission to issue the OUL as well as the LGPL (so very specific), but there was one major problem with this - dealing with license violations by others. Only a copyright holder or equivalent can legally pursue a license infringement, so not having that right would actually cause problems (this came up when talking to a lawyer about the recent license violation issue). In that case it was code where copyright was simple (just myself and one or two others) so I could resolve it, but it meant that in future I had to deal with the copyright issue, when previously I'd tried to avoid asking people to transfer copyright because I thought they should still own it. The joint copyright approach is one I discovered in another large open source project (I forget which!) and seemed perfect - contributors still get to keep their own rights over the code they wrote, while still assigning us the rights we need.

About the German issue (everything seems to be different there ), that's why we say in our license that if assigning the copyright (jointly) is invalid, then you grant an non-exclusve, royalty-free yadda yadda license for us to use it as we see fit (which is equivalent in practical terms).

Thanks! That'll definitely help

My only remaining issues before able to open-source now is one I posted here for the GPL experts:
https://sourceforge.net/community/forum ... hp?id=5895