Proprietary graphics in a free program?

[Tord Romstad]

Thanks for sharing your opinion, Greg!

I've been contacted by a guy who wants to make a commercial chess program based on the iPhone version of Glaurung. Because my program is GPLed, he is free to do so, as long as his commercial program is also delivered under the GPL. He understands this, and intends to release all changes he does to my source code, so everything is OK so far.

The problem is that he intends to hire a professional graphic designer to draw things like piece images, the icon, and perhaps textured board squares, and keep the graphics proprietary. He wants to know whether the GPL allows this, and I honestly don't know myself. Does anybody else know anything about this?

Tord

My opinion is no. It is certainly against the spirit of the license (which license?

GPL, as I said: Version 3, to be more specific.

You didn't say, not that that would help me) but I don't think here is the best place to get a definitive answer as to whether this is allowed. Does the FSF have some place to ask these questions?

I tried posting a question to gnu-misc-discuss@gnu.org, but it hasn't appeared there yet. I suppose the list is moderated, and that my message will appear there later.

Assuming you have clear ownership of this version of Glaurung, no open source graphics or anything from someone else, you could certainly sell him a license to do this if you want

In principle I could, but it seems like too much trouble. I prefer not to sell anything.

Tord

[Tord Romstad]

> you could certainly sell him a license to do this if you want

Right. As the author you can distribute the program under another license.

I can, but I don't want to do that. The idea of somebody else earning money from something which is 99% my work is a little strange enough to me by itself, but as my program is free, I can't really object. Anyone is free to sell Glaurung, as long as they observe the license. Giving someone an exception to the license just in order to make it easier for him to sell his program without giving anything back to the community seems absurd, however. What would be the point in doing that?

Tord

[Tord Romstad]

Depends. If this is "one program" then that is not allowed under the GPL. And I believe that the Iphone is brain-dead in that regard. If the GUI is a separate program that somehow executes the engine (unix fork/execve for example) then there is no problem at all...

It's true that a third-party application is not allowed to fork off any additional processes or start other programs (you can do it just as easily as in any Unix, but Apple won't accept your app), but this is just a technical annoyance. I don't see how it has any relevance to my question about the GPL. Both my engine code and my GUI code are GPLed, and whether or not they are both contained in the same executable makes no difference for how the code can be used.

Tord

[hgm]

I solved a similar situation for WinBoard in connection with Superchess: someone wanted to distribute WinBoard + Fairy-Max as a Superchess program, but wanted it to play with the piece symbols that are used in Superchess, rather than the normal Chess symbols. But he wanted to keep the Superchess symbols proprietry.

The solution we used was to have him offer the Superchess symbols separately, as a true-type font, and use the WinBoard font-based rendering option. The font was offered for download separately, which was not too much of an inconvenience, as it has to be installed in a different folder than the software anyway (namely the system fonts folder).

My understanding is that it is OK to have GPL'd software cooperate with other software or use non-GPL'd data if the non-GPL'd stuff is not packaged with it, and it takes at least one human action to obtain it. So you can have the installer of the GPL'd software ask the question "Should I also install the proprietry graphics?", and if people click YES, and from then on the download and installation proceeds automatically, there is no legal problem. They are then separately obtained packages, and if a user decides then to somehow combine the packages for its own personal use, there is no way to legally prevent this. The crux is that the command to combine the GPL'd software and the non-GPL'd components must come from the one who ues the software. It would be a GPL infringement to distribute the combination.

So if I were selling an improved evaluation function for Fruit, together with a script that downloads the source code of Fruit, compiles it, and links it with my proprietry evaluation code, I could sell that under any license I please. Provided it is the end user that invokes the script by clicking it. The executable he thus obtains could not be distributed by him; if he did that, he would be violating the GPL. (And, most likely, the license on the commercial package as well, as I of course don't want him to distribute it.)

[bob]

Depends. If this is "one program" then that is not allowed under the GPL. And I believe that the Iphone is brain-dead in that regard. If the GUI is a separate program that somehow executes the engine (unix fork/execve for example) then there is no problem at all...

It's true that a third-party application is not allowed to fork off any additional processes or start other programs (you can do it just as easily as in any Unix, but Apple won't accept your app), but this is just a technical annoyance. I don't see how it has any relevance to my question about the GPL. Both my engine code and my GUI code are GPLed, and whether or not they are both contained in the same executable makes no difference for how the code can be used.

Tord

What does matter is whether or not the new GUI uses your source, which would make it GPL'ed automatically, or whether it just executes your executable, which would not make it GPL.

Of course, as Jon pointed out, you can grant a private license to anyone you want, since you hold the copyright to the source... You can continue to distribute a GPL source, while giving that same source to a specific user under a different license, if you choose...

[Dirt]

So if I were selling an improved evaluation function for Fruit, together with a script that downloads the source code of Fruit, compiles it, and links it with my proprietary evaluation code, I could sell that under any license I please. Provided it is the end user that invokes the script by clicking it. The executable he thus obtains could not be distributed by him; if he did that, he would be violating the GPL. (And, most likely, the license on the commercial package as well, as I of course don't want him to distribute it.)

The legal system tends to frown on such maneuvers to circumvent copyright. Your intent here is for your customers to end up with a non-GPL derivative of Fruit. A little search show that this company doesn't think that selling software patches to their GPLed program is legal without a commercial license.

[Dann Corbit]

I've been contacted by a guy who wants to make a commercial chess program based on the iPhone version of Glaurung. Because my program is GPLed, he is free to do so, as long as his commercial program is also delivered under the GPL. He understands this, and intends to release all changes he does to my source code, so everything is OK so far.

The problem is that he intends to hire a professional graphic designer to draw things like piece images, the icon, and perhaps textured board squares, and keep the graphics proprietary. He wants to know whether the GPL allows this, and I honestly don't know myself. Does anybody else know anything about this?

Tord

I do not think it is allowed even by LGPL. If you improve the tool, then you have to publish your improvements.

You would have to sell (or give) him a separate commercial license. That is your right as originator of the program.

[Dirt]

GPL, as I said: Version 3, to be more specific.

Whether or not you were using version 3 is what I was asking. I haven't even read the V3 license, so I mostly just assume it's about the same as V2. If there are any real experts around here, though, that might be useful information.

[Tord Romstad]

I tried posting a question to gnu-misc-discuss@gnu.org, but it hasn't appeared there yet. I suppose the list is moderated, and that my message will appear there later.

My message to the above mailing list has now appeared, and I got a helpful reply: Apparently it is OK to use my source code in the way I described, as long as the source code builds correctly and gives a fully usable (albeit perhaps not quite as good-looking) application even without the proprietary graphics files.

Tord

[Tord Romstad]

Depends. If this is "one program" then that is not allowed under the GPL. And I believe that the Iphone is brain-dead in that regard. If the GUI is a separate program that somehow executes the engine (unix fork/execve for example) then there is no problem at all...

It's true that a third-party application is not allowed to fork off any additional processes or start other programs (you can do it just as easily as in any Unix, but Apple won't accept your app), but this is just a technical annoyance. I don't see how it has any relevance to my question about the GPL. Both my engine code and my GUI code are GPLed, and whether or not they are both contained in the same executable makes no difference for how the code can be used.

What does matter is whether or not the new GUI uses your source, which would make it GPL'ed automatically, or whether it just executes your executable, which would not make it GPL.

As far as I understood the e-mail I received, there won't be a new GUI at all, just my own GUI with some customizations and a few proprietary graphical images.

Of course, as Jon pointed out, you can grant a private license to anyone you want, since you hold the copyright to the source... You can continue to distribute a GPL source, while giving that same source to a specific user under a different license, if you choose...

Yes, but as I explained in my reply to Jon, I don't want to do that.

Tord