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Licensing Issues

Wednesday, August 10, 2005

All the code I release through my blog is licensed according to the zlib license. I basically wanted a license that allows you to do whatever you want with the code. The only thing I want in return is the recognition that I wrote the code. Well, Gianfranco Berardi decided to use my code and the first thing he had to do was research what he could and could not do with it. That's not what I wanted! You should be able to just use the code without worrying about the license, especially if you're only trying to learn game programming.

The Main.cpp file that is distributed with my game engine code basically just has one statement: start the game engine. It also contains some necessary C++-stuff and a copyright notice, but that's all pretty insubstantial. It seems rather ridiculous to me that you need to credit me for that single, simple statement, but that is what the zlib license requires.

So, now I wonder whether the zlib license is the right choice for what I intend. If you use my GameEngine class and you make small changes here and there, then all I'd like you to do is mention that the gist of the code was written by me. A link to my web site would be nice, so other people can find the code and the accompanying tutorial themselves. If you write your own classes and use bits of my code here and there, then I don't need anything more than a message that says something like 'some parts of this code were written by Joost Ronkes Agerbeek'.

Does anybody know of a license that's even less stringent than the zlib license?

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GBGames says:

Actually, what I was told in the email from LGDC was that I didn't have to note each and every change. I just had to note somewhere, like in a README, that I am using code from you (giving credit where it is due) and that I have modified it (not making it seem like the credit belongs to me). It actually turns out to not be as complex as it may have sounded in my blog post. It is actually much like what you describe in the second to last paragraph. Since I wanted to release under the GPL, that meant that I had to worry about releasing the source and the licensing issues with that. People who won't release the source won't have to worry about it as much as the concern I had just dealt with how I would deal with comments and crediting. But if you still want to find an alternative, the new BSD license is probably what you want. It is basically "do whatever you want with it so long as basic credit is given to me", like the MIT license. The old BSD license used to require an advertising clause, which people decided wasn't open enough to be an OSI approved license. But again, I think ZLib should be fine and I think these three licenses are really only different because of name only. OSI is working on license proliferation, so hopefully we'll have only 5 basic licenses to deal with in the near future. I had no experience with working on multiple code bases, let alone different licenses, so I spent a good portion of my development time last week making sure that I could legally do what I was going to do.

Wednesday, August 10, 2005 6:24 PM

mahlzeit says:

You could use the "No problem bugroff" license: ;-)

Wednesday, August 10, 2005 11:36 PM

Joost Ronkes Agerbeek says:

I actually like the "No problem Bugroff" license. :-) I had a look at some open source licenses. The BSD and MIT licenses are more restrictive than the zlib license, since they require you to reproduce the copyright notice and the license text with if you distribute it in binary form. I don't want that. A couple of other licenses were close, but mostly they were either too long or not entirely clear. I want a license that puts people at ease, not frighten them. I'll probably end up with something like this: you can use this source code for whatever you want. The only thing I ask is that, if you modify and distribute the source code, you acknowledge I wrote part of the code and that you provide a link to my web site. In the mean time, just use my source code and tell others about it. :-)

Thursday, August 11, 2005 8:50 PM

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