[DIY] making html5 wesnoth-themed roguelike

Discuss the development of other free/open-source games, as well as other games in general.

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Re: [DIY] making html5 wesnoth-themed roguelike

Post by Shadow_Walker »

iceiceice wrote:I think there is a misunderstanding here -- GPL certainly does not prohibit the selling of the content.
Ah, okay then. Voids my previous statement, I guess.

ps: I still think that MIT license is waaay more open in a sense that it allows to do anything you like with the subject. Currently, having just one image or sound track from Wesnoth in one's project means that whole project should suddenly become GPLed and developer is now obliged to publish his own code publicly. What if I am scared by the ugliness of my code and do not want to expose it to wide audience? Does it mean I should not distribute my game freely until I comply with GPL terms? That's plain crazy.
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Re: [DIY] making html5 wesnoth-themed roguelike

Post by iceiceice »

I must confess, I don't completely myself understand the implications of GPL in regards to art, and despite searching, I haven't been able to find a legal authority on the internet that explains it. If someone knows a *very* authoritative explanation, meaning, written by a judge or a lawyer / group of lawyers, not just some FSF / Debian project person (unless they are also a lawyer), I would greatly appreciate it.

However, the prevailing wisdom about how the GPL applies to combined works seems to be that it's roughly like this:
  • If you write code derived from GPL code, that code must be GPL.
  • If you copy-paste GPL code into your existing code-base, for instance, so that it is compiled along with your code, then all the code must be GPL.
  • If your project compiles as one unit, and you want to link with say, a GPL library, again, your code must be GPL. This is where the GPL differs from LGPL: Libraries under the LGPL may be linked with without forcing all your code to be similarly licensed.
  • If your project compiles to a single executable, and makes use of a GPL executable via system calls, using a function like this, for instance: http://linux.die.net/man/3/system, that is okay and permitted under the GPL.
I can't say that I fully understand why "linking" is the place at which the line is drawn, given that the text of the license makes no mention of linking -- afaict this is part of an FSF legal theory about how the court should interpret certain ideas from copyright law in the context of software. To the best of my knowledge hasn't actually been tested in court -- but I could be wrong, and this idea seems pretty widespread now.

Anyways, in regards to art, one developer I know took the stance "why would GPL art infect your game? You don't link with it."

This stance is promoted in this article:
On Unix-like operating systems, applications typically store resource data such as icons, sounds, and splash screens separately, somewhere within the /usr/share hierarchy. As a developer, you can code your app to access those resources in any number of ways.

Hard-coding the paths to your icons, Smith says, probably results in what copyright law could deem a single, combined work. In that case, Smith would advise ensuring that the icons had a GPL-compatible license.

But mechanisms do exist to make a clean separation between the code and the data. "Most graphical toolkits are written such that applications can request stock icons, such as the 'zoom in' icon, and the toolkit will load and display a particular image based on the user's theme and other preferences."

"This level of abstraction," he says, "is enough that I haven't met anybody who's particularly concerned about compatibility between the icon at the bottom of the stack and the application at the top."
So, it's not actually clear that using GPL art requires your game engine to be GPL. It's also not clear that using a mix of GPL art / non-GPL art in your game is prohibited.

I think there was another thread on these forums from a long time ago, where I argued for a more strenuous interpretation. All I can say is that, most people that I've talked with seem to think that GPL is a poor choice for art assets like images and sound, not because it is restrictive, but because it is largely ineffective -- a large part of the terms of the GPL just don't actually do anything when you apply it to media like an image or sound. Instead it really only makes sense as a code license. Or so I am led to believe :hmm:

Edit: I should add:

There was an email thread some months ago where the developers discussed relicensing all art assets under CC-BY-SA.
My understanding was that there was not much opposition to this. However to the best of my knowledge nothing happened.

There were some questions also about how it would affect addons if we did that.
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Re: [DIY] making html5 wesnoth-themed roguelike

Post by Shadow_Walker »

iceiceice wrote:developers discussed relicensing all art assets under CC-BY-SA.
That would be super!
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