Ras wrote:And why? If the SF authors had gone the same way as these people, they would not even have SF sources to tinker around with. The point of the GPL is to give the people later in the chain the same options that those earlier in the chain had.
Because sharing closed source is a compromise:
The users get something they didn't have before, allowing them to do things previously unavailable.
The programmers get to share their work, without revealing their secrets.
You're not going to have those secrets, the thread is full of programmers that only care about having the open source of those secrets, but hopefully there's users out there that would appreciate closed sharing, because for them open source makes no difference, as they're not programmers.
So the problem is the Licence itself that doesn't allow this compromise.
And no, if Stockfish had a different Licence it wouldn't be any weaker, what would happen is something like this:
Suppose I make a closed source Stockfish patch that detects certain pawn formations of the enemy King, and when they happen it checks for stuff, and if that stuff is in effect, Stockfish launches all their pieces against the enemy king. It works 2/3 of the time and makes Stockfish 20 elo stronger.
I release the patch (in, eh, an alternaste reality where this is legal?) for the benefits of users that can patch their Stockfish and have this option (1/3 of the time this doesn't work and default is better, so an user can be stronger by using the best SF in the board's situation.)
Would you say that it's damaging the open source project as SF had it missing?
No, Stockfish has already a team full of people that dedicate their life to improve it, so now they can see how the patched one behaves, and replicate its behavior with code on their own, probably better than me so actually they didn't need my patch and only needed to see the idea in action.
And I know because I have done stuff like this over the years, not only for Stockfish but for Rybka back when I beta tested it. You don't need to apply some closed source patch for this, it suffices to explain some concept to people, some wanted behavior, an they can produce code quickly that produces that behavior. And that behavior or something close makes it into the engine and it improves.
So if Stockfish had a different Licence that allowed people to provide closed source patches for it, the ideas would stop being private, people can take a look at the behavior and produce open source that does it.
This "open your source or don't share anything" philosophy is damaging.