I'm making a runtime environment for Squirrel that includes embedded functions for basic I/O needed in games. The idea is that it would just run Squirrel files (.nut or .sq) or its own format for multiple packed scripts. Basically, the RE contains all the functions for drawing, getting input, handling sound, loading resources, etc., but doesn't actually do anything on its own. The Squirrel scripts have all the game logic and tell the RE what to do.So far, the code is available under GPL3, but someone who recently got interested in the project tells me that GPL3 is a bad idea because it'll force anyone who makes a game with it to open source their game as well. This confuses me, because unless they're actually modifying the runtime itself to make a game out of it, why would this happen? The scripts it runs aren't actually part of the runtime, so shouldn't whoever writes them be able to determine their own license for it?The way I see it, since the Squirrel scripts aren't actually part of the runtime, and could possibly even be run by another program altogether, assuming they used the same names in their embedded functions, then the license of the runtime shouldn't apply to the programs it's being used to run. Of course, I don't know if this is right or not, which is why I'm here.If I make a runtime with a GPL license, does that license apply to programs that are intended to be run in it but not actually a part of it? Or are they separate and people making games with it shouldn't worry?Also, in case anyone is wondering, the libraries I'm building it with are all either X11/MIT or ZLib licensed.Squirrel is a scripting language. It's been used in games like Portal 2, Left 4 Dead, GTA 4 and 5, and a few others I can't remember off the top of my head. Someone else made a game development kit for it, too, but it's specifically designed for Android/iOS. I want to make one that's for PC.
GPL in a runtime environment
mit;gpl 3;zlib
Generally speaking, the GPL license does not necessarily apply to the input of a program. For example, the GNU bash interpreter is GPLv3 licensed, but bash scripts are not all GPLv3 licensed, and some people make proprietary scripts.However, it could be a gray area if your program and its input are intimately coupled (and that notion is not easy to define). You might need to ask a lawyer (which I am not).Look at the GPL FAQ question :If a programming language interpreter is released under the GPL, does that mean programs written to be interpreted by it must be under GPL-compatible licenses?And the same FAQ tellsWhen the interpreter just interprets a language, the answer is no. But read more about that issue. If there are several interpreters of Squirrel you are on the safe side.PS. I have absolutely no idea about what Squirrel is.