StockFish engine

Discussion of chess software programming and technical issues.

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andrejcher
Posts: 12
Joined: Tue Jan 11, 2011 1:58 pm

Re: StockFish engine

Post by andrejcher »

Hm? :D
zamar
Posts: 613
Joined: Sun Jan 18, 2009 7:03 am

Re: StockFish engine

Post by zamar »

andrejcher wrote:I've checked a lot of open-source libraries due license they have for iPhone. Most of them have custom one.
The word "custom" is the problem. We are programmers not lawyers. If we get FSF or some other big reliable organization to publish a license which fulfills the needs, we might consider using it.

For starters none of us are native English speakers. We are not capable of writing a license which can 100% sure stand in court. And we are not prepared to invest dozens of hours for this issue.
Joona Kiiski
andrejcher
Posts: 12
Joined: Tue Jan 11, 2011 1:58 pm

Re: StockFish engine

Post by andrejcher »

Even publishing all source code under GPL will not help.

http://www.zdnet.com/blog/open-source/n ... store/8046
zamar
Posts: 613
Joined: Sun Jan 18, 2009 7:03 am

Re: StockFish engine

Post by zamar »

andrejcher wrote:Even publishing all source code under GPL will not help.
http://www.zdnet.com/blog/open-source/n ... store/8046
I'm afraid that if Apple refuses to distribute the GPL-programs, there is very little we can do about it... Relicensing is not an option and GPL-exceptions are just too risky step to take.
Joona Kiiski
svchbe

Re: StockFish engine

Post by svchbe »

Apple has only removed vlc from the appstore after one of the copyright holders complained about infringement of his copyright and was threatening to sue them.
Apparently all other main authors agreed to the publication of this app.

So this is an exceptional case anyway and no indication that Apple is taking any general action against GPL licensed software.

As far as I am concerned publishing unchanged GPL licensed code as a part of an app on the appstore without providing the source code is probably breaking the GPL anyway, because of the static linking requirement.

I don't think that the additional restrictions imposed on software published on the appstore are a clear violation of the GPL. As one could argue that the restrictions are requirements of the publication system. In my opinion this is allowed by the GPL as long as these restrictions don't need to be applied to the source code and other publications of this source code in binary form. (if this would apply allmost all GPL software would be in violation on the windows/macosx platforms, because these systems impose additional constraints on the binary releases).
andrejcher
Posts: 12
Joined: Tue Jan 11, 2011 1:58 pm

Re: StockFish engine

Post by andrejcher »

diep
Posts: 1822
Joined: Thu Mar 09, 2006 11:54 pm
Location: The Netherlands

Re: StockFish engine

Post by diep »

zamar wrote:
mcostalba wrote: Personally I don't see problems in this, actually I could even foreseen the possibility of a double GPL / LGPL licensing alltogheter, indipendently from the target platform, but Tord and Joona agreements are both mandatory in this case.
As stated by others, releasing under LGPL won't solve the problem. Personally I might agree on GPL exception under certain strict rules:

* There must be no other way around to use SF-engine in product.
* Full source code of the product in question must be sent for SF-team for examination
* Author of the product must report all the changes made to SF source to SF-team. Changes must be trivial in nature (no functional change).
* Each new version of the product must be sent for SF-team for examination before releasing.
* SF-team can deny releasing the product or new version of it any time without needing to explain anything.

Even then there is a risk that we are opening pandora box, and our development team turns into a post office.
Oh comeon don't be silly - ask big cash from the guy.

Vincent
diep
Posts: 1822
Joined: Thu Mar 09, 2006 11:54 pm
Location: The Netherlands

Re: StockFish engine

Post by diep »

andrejcher wrote:I've checked a lot of open-source libraries due license they have for iPhone. Most of them have custom one.

For example check popular 2d game engine cocos2d (http://code.google.com/p/cocos2d-iphone/wiki/FAQ) and its license

"cocos2d for iPhone is licensed under the 'cocos2d for iPhone license'. Basically it is like a LGPL license but allows you to use the library as a static library or by including the cocos2d for iPhone sources in your project.

Remember that cocos2d for iPhone follows the copyleft idea. So if you improve the library, send me the patches or make them public so that I can include them in future releases."

And it doesn't require to make product open source.

Maybe the same can be done with SF engine? I can prepare open source library for static linking and guide about integration it.

Your thoughts?
Iphone is easy to solve. Ipad isn't. First generation ipads need static linking into same executable and another few problems.

Seems key problem with ipad is that apple released it too soon. They released it using also an inferior processor than initial marketing announcements. In the end it is a slowish 1Ghz chip instead of a dual core or quad core chip, and they use an old operating system instead of a newer version that allows multithreading and multitasking.