It probably seems like beating a dead horse at this point but after additional research I've come across more information relating to the use of artwork licensed under GPL that should be shared. On the GNU license recommendations page they suggest how to license assets that are not program code.
Works made for practical use by software may include icons, graphics, fonts, and geographical data (these examples provided by GNU). They are considered in the Other Data for Programs section specifically because they are not interactive software. There is no way to execute graphics data; the only meaningful way to understand graphics data is in the same context as text or metadata. They cannot cause a logical sequence of events on their own, they doesn't rely on a particular program or software to be meaningful, and if they are not created for a specific product they are considered an independent set of data. For these reasons it makes little or no sense to apply GPL to graphics unless you are trying to protect them in the context of a project. Graphics under GPL that are not made for a specific project are essentially free to use in any project under any license since GPL allows for dynamically linking to non-GPL software (assuming it does not form a dependency). Graphics cannot form a dependence (they have no logic of their own) because they are recognized the same as flat text and cannot cause a project to be held under GPL by themselves.
The Free Software Foundation views icons, graphics, and text as being flat data. They mention this very clearly in their license recommendations page and recommend NOT using GPL for these types of assets if they stand on their own. Graphics under GPL that aren't tied to something are essentially free to use without restriction in any type of project that doesn't impose a conflicting license restriction.
You can use GPL art in a project that's not GPL as long as you identify the art separately from the project. Check with the artists if you have questions.
Long Version
Since I went to all the trouble of mentioning the license stuff for the base LPC art I'll include the stipulations about art and the GNU General Public License (GPL). Here is a link related to works covered by GPL and specifically about artwork under GPL:
The significant paragraph in this wall of text is here:
A GPL'ed Work of Art may be distributed as part of a "commercial" Catalog or Compilation provided its status along with The GNU General Public License are mentioned.
This refers to a clause in the GPL that allows for GPL software interacting with another software that is not contained by the GPL. In plain language this means you need to tell people about the part of your program that is licensed GPL separately from those parts that are not. Without this clause every software released under GPL would only be usable under an operating system and OS environment that's entirely made up of GPL components. The significant paragraph in the GPL license terms is here (under the heading 1. Source Code.):
The "Corresponding Source" for a work in object code form means...
Toward the end it mentions the stipulation about dynamically linking a non-GPL software to a GPL software. It's reasonable to treat art as separate software from program logic because it's not the same language, format, or even interpreted by the same parts of a compiler or operating system when used. That said, most find it acceptable to use GPL artwork in a closed source project without complaint because most consider art separate from program code. Since artwork can be used independently from program code it stands to reason that it's an independent software. You might want to check with the artists if you have questions about this.
You can use LPC artwork in a commercial project as long as you give attribution and clearly mark the artwork separately from the program you make. You don't have to double or triple check anything. I know the FAQ is a little confusing and it does give you some slightly misguided information (although well intentioned) but it's not an issue to use LPC in commercial work.
The only part I'd be concerned with is the anti-drm clause in both GPL and CC licenses. You'll want to be sure to ask the artists to waive this part of either (or both) licenses if you plan to release an iOS app (iPhone app or desktop program). I know several people have openly given blanket permission that waives this part of both licenses, Sharm is among those people. I have given the same waiver for the anti-drm clause. I can't recall where the forum thread was about that so I might start a new one and ask all those interested to leave their permission where it can be easily found.
By the way, I'm a programmer, not an artist. Almost all the art I have listed on OGA I paid to have made. I know next to zero about making graphics but I have good graphic artist friends ;)
One thing you should note is all the base Liberated Pixel Cup art is dual licensed CC-BY-SA and GPL. Here is the page explaining how that works (under art phase rules):
This mainly means you need to mention the artists names, mention the LPC, and include a link to OpenGameArt.org somewhere in your credits. You'll want to look at any specific entries for more details. All that aside it's all very usable content and still all free, you just end up with a lengthy credits file that includes reference to several free licenses and a lot of people's names.
Here's a common question about how to give attribution:
It's highly appreciated if you put any derivative works based on LPC stuff back on OGA too by the way. Here are more useful LPC links that help in game development:
That's awesome.
This is a related thread:
http://opengameart.org/forumtopic/anti-drm-waiver
This is not such an old thread but I still don't wish to be seen as resurrecting it but this is related:
http://opengameart.org/forumtopic/anti-drm-waiver
This is an old thread and I don't wish to be seen as resurrecting it but this is related:
http://opengameart.org/forumtopic/anti-drm-waiver
This is an old thread and I don't wish to be seen as resurrecting it but this is related:
http://opengameart.org/forumtopic/anti-drm-waiver
It probably seems like beating a dead horse at this point but after additional research I've come across more information relating to the use of artwork licensed under GPL that should be shared. On the GNU license recommendations page they suggest how to license assets that are not program code.
http://www.gnu.org/licenses/license-recommendations.html
Works made for practical use by software may include icons, graphics, fonts, and geographical data (these examples provided by GNU). They are considered in the Other Data for Programs section specifically because they are not interactive software. There is no way to execute graphics data; the only meaningful way to understand graphics data is in the same context as text or metadata. They cannot cause a logical sequence of events on their own, they doesn't rely on a particular program or software to be meaningful, and if they are not created for a specific product they are considered an independent set of data. For these reasons it makes little or no sense to apply GPL to graphics unless you are trying to protect them in the context of a project. Graphics under GPL that are not made for a specific project are essentially free to use in any project under any license since GPL allows for dynamically linking to non-GPL software (assuming it does not form a dependency). Graphics cannot form a dependence (they have no logic of their own) because they are recognized the same as flat text and cannot cause a project to be held under GPL by themselves.
The Free Software Foundation views icons, graphics, and text as being flat data. They mention this very clearly in their license recommendations page and recommend NOT using GPL for these types of assets if they stand on their own. Graphics under GPL that aren't tied to something are essentially free to use without restriction in any type of project that doesn't impose a conflicting license restriction.
Short version
You can use GPL art in a project that's not GPL as long as you identify the art separately from the project. Check with the artists if you have questions.
Long Version
Since I went to all the trouble of mentioning the license stuff for the base LPC art I'll include the stipulations about art and the GNU General Public License (GPL). Here is a link related to works covered by GPL and specifically about artwork under GPL:
http://gnuart.org/english/gnugpl.html#SEC5
The significant paragraph in this wall of text is here:
This refers to a clause in the GPL that allows for GPL software interacting with another software that is not contained by the GPL. In plain language this means you need to tell people about the part of your program that is licensed GPL separately from those parts that are not. Without this clause every software released under GPL would only be usable under an operating system and OS environment that's entirely made up of GPL components. The significant paragraph in the GPL license terms is here (under the heading 1. Source Code.):
http://www.gnu.org/licenses/gpl.html
The paragraph you want to read starts with
Toward the end it mentions the stipulation about dynamically linking a non-GPL software to a GPL software. It's reasonable to treat art as separate software from program logic because it's not the same language, format, or even interpreted by the same parts of a compiler or operating system when used. That said, most find it acceptable to use GPL artwork in a closed source project without complaint because most consider art separate from program code. Since artwork can be used independently from program code it stands to reason that it's an independent software. You might want to check with the artists if you have questions about this.
You can use LPC artwork in a commercial project as long as you give attribution and clearly mark the artwork separately from the program you make. You don't have to double or triple check anything. I know the FAQ is a little confusing and it does give you some slightly misguided information (although well intentioned) but it's not an issue to use LPC in commercial work.
The only part I'd be concerned with is the anti-drm clause in both GPL and CC licenses. You'll want to be sure to ask the artists to waive this part of either (or both) licenses if you plan to release an iOS app (iPhone app or desktop program). I know several people have openly given blanket permission that waives this part of both licenses, Sharm is among those people. I have given the same waiver for the anti-drm clause. I can't recall where the forum thread was about that so I might start a new one and ask all those interested to leave their permission where it can be easily found.
By the way, I'm a programmer, not an artist. Almost all the art I have listed on OGA I paid to have made. I know next to zero about making graphics but I have good graphic artist friends ;)
One thing you should note is all the base Liberated Pixel Cup art is dual licensed CC-BY-SA and GPL. Here is the page explaining how that works (under art phase rules):
http://lpc.opengameart.org/content/lpc-rules
This mainly means you need to mention the artists names, mention the LPC, and include a link to OpenGameArt.org somewhere in your credits. You'll want to look at any specific entries for more details. All that aside it's all very usable content and still all free, you just end up with a lengthy credits file that includes reference to several free licenses and a lot of people's names.
Here's a common question about how to give attribution:
http://opengameart.org/forumtopic/question-about-attribution
It's highly appreciated if you put any derivative works based on LPC stuff back on OGA too by the way. Here are more useful LPC links that help in game development:
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