What liscense specifically are you asking about, pretty much every "free-as-in-freedom" license should be compatible with one of those 2.

I also notice that the entry form requires "GNU GPL version 3 or later", while the rules only mentioned "GNU GPL 3.0". Not happy either.

On second thought, I am not a native speaker. Is "all my software source code is GNU GPL version 3 or later" satisfied by the code being licensed under GPLv3 (because the version nmumber 3.0 is greater or equal to 3)? That would be fine, of course ;-)

If the requirement is in fact to add the "or later" clause to the GPL, then it is impossible to use new original content based upon art phase content by other people: We did not receive the art phase content under the GPLv3+, only under GPLv3. Even the base assets are not GPLv3+ (except for the demo), so any art phase content based upon base assets which in fact was licensed GPLv3+, was done so illegally.

I am very unhappy as well.

Andrewj: No, we did not change the rules.  But the issue of compatibility is not necessarily our rule in the first place... if you're using CC BY-SA / GPLv3 works in a larger combined work (and the liberated pixel cup assets are as such) it is probably the case that any other free-as-in-freedom licensed stuff will have to be compatibly licensed with one of them... and that's less our rule than the rule of the way this licensing stuff works itself.  So technically we did not change the rules, but if you're using LPC artwork, the form is still "in effect" correct.  I can do these two things: I'll ask BartK what we should do about possibly changing the form wording (not sure if that's a good idea or not) and if you were working on a project and were using an incompatibly licensed existing free-as-in-freedom licensed set of assets, if you can ping me in #liberatedpixelcup on freenode tomorrow (sunday the 29th) or Monday (the 30th) I'll see if we can look at what other resources might be available.

Sorry... one of the goals of the LPC is to help people better understand licensing, and it's clear we did a poor job in this case.  I'll consider that my own fault.

caeles: you are right, the "or later" should not be added to the assets side (but should be on the code side)... I'll ask BartK to remove that bit. of phrasing.  For now, you have my permission to submit with that checkbox assuming that bit is already going to be removed.  My bad.

Personally, I don't mind the "or later" clause and would gladly relicense my assets as needed. I'm sure most of the contributors would feel the same way, so why not throw them an email at the very least?

Finally, regardless of how many licenses a piece of art has, you can choose the one you'd like to use(From those available), and for art, I'd always side with CC instead of GPL. Its less of a legal nightmare, I think.

@cwebber:

I am not sure that the sum of all art files of a game necessarily is a combined work, rather than a mere collection. And in the latter case there is no license compatibility issue (except maybe for weird licenses not yet mentioned).

Now for the "or later". I am never happy with using it, because it means licensing my work under terms unknown to me. If you insist on keeping it for the code side... I will have to reconsider whether I want to submit. Not doing so would be very frustrating, of course. Especially at this time of the competition. Well at least you would have to admit that you did, as andrewj suggested, change the rules: The rule page does not mention the "or later".

I still think you're making much ado about nothing, regarding the "or later" clause.

A) By the time "GPLv4" is released, your code and game will be long lost and forgotten.

B) It only applies to the entry you submit, not further copies / bugfixes

C) Assuming GPLv4 grants less freedoms, people would stick to GPLv3

D) Assuming it grants more freedoms and someone does use your code because of it, attribution towards you still stays.

Just sayin'

Mushio,

A) You're assumi

Not sure why my comment was struck down in the prime of life. Monsters :_:

In reponse to C) and D) there are real concerns about changing terms.

For example, if I use "GPL v2 or later" code in my project I'm going to make my derived work availble as GPLv3 so that anyone who uses the derivitive code in their product must not strip users of the ability to install modified versions on the machine.

In a similar way I would not make my code "GPLv3 or later" because I can't be sure the anti-tivoization clause will stay in future versions.

I'm using GPL2+ in my project so that it will be compatible with more other free software.  At some point I'll probably add other licences for the same reason.  Maybe MIT or one of the BSD licences.

I've had a lot of trouble with some software that was released with an extremely free licence way back in the 90's, before the world had standardized on the small number of common licenses we have now.  It turns out not to be compatible with the GPL2 or 3, and it's a constant nuisance almost every time I want tto use it.  The company that produced it and more-or-less gave it away has undergone a series of takeovers, and no one we can find has the slightest interest in the project any more.  We cannot find anyone to relincence it.  The result is permanant incompatibility.

I ready the topic and I still have no idea. With a yes/no answer: can we use GPL2 (strict) art resources in our games? I hope there is nothing wrong with that. There are 6 images we have used this way and it would be too bad to replace them with filler art.

Sorry about the issues with the form.  I've removed the "or later" from the GPL v3 part, and also changed the other part to say any FSF approved free-as-in-freedom license.

Note on GPL v2 assets:  My personal read of what the FSF has said in the past is that including assets with a game is bundling, which is okay for mixing licenses that aren't strictly compatible.  That said, Chris thinks it's debatable whether a game constitutes a work, which would trigger the GPL.  If you're including GPLv2 assets along with a game, I would recommend that you get permission from the author of those assets just to make sure you're in the clear.

Bart

@bart: its from manaworld assets and they say its strictly gpl2, I am almost sure that art assets in a game is a collection, not a derivative work. But is it a problem for LPC?

Sorry for reopening the thread, but I thought I'd better do a heads-up:

The submission form now requires FSF approval of licenses. It was not mentioned in the rules. Here is why that affects my entry (copied from my submission metadata):

The game uses non-original code from the game anatris (as annouced in
http://opengameart.org/forumtopic/getting-an-early-start-on-the-coding-p...
)
That code is under a free-as-in-freedom license, albeit not under an FSF
approved one (the license in question is too new to have undergone FSF approval).
See README for the details. As the condition of FSF approval has appeared only
very recently, I submit nevertheless.

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