Finding clones...

[mclane]

i would say christophe ignores you.

IMO nothing can damage rybka3 sales because rybka3 is the strongest program in the moment.

the people always want to buy the strongest program.

(btw. this is indirectly a repetition of what christophe said with his Mr.Right statement. again... no insult. just a general saying about how the people decide what to buy.)

ABBA once made a song about it: "the winner takes it all".

was that an insult ? no.

[rhollay]

So in my opinion:
- Rybka 1.0 is not a clone of Fruit 2.1, it is somehow different and better
- Rybka 1.0 started as the source code of Fruit 2.1

We have a different opinion what clone means. Starting with the source code would violate the GPL even if every single line is changed. So I would call this cloneing.

But as I stated several times before, it must not be illegal in case the original author agrees.

Alex

Then, what is the purpose of "open source" chess programs at all?
So you can study other's program, but be careful not to study it very well!
Because if you remember too much of it then there's a possibility that you will unintentionally repeat
the program's structure, or parts of code when writing your own program!

You can read other programmer's code just to learn what you must not done in your own...

So open source programs are a good way to "copyright" code and ideas?

If Fruit had not been released as open source then we would never have
seen such degenerated debates about cloning here, and stupid and childish
"psychological" dissertations about envy - not envy in a forum about Computer Chess.

[Zach Wegner]

You must willy nilly enter the Rybka forum. He doesnt write here.

He doesn't write at the Rybka forum either, at least not about this issue.

[swami]

Alexander Schmidt wrote:

$2. You may modify your copy or copies of the Program or any portion of it, thus forming a work based on the Program, and copy and distribute such modifications or work under the terms of Section 1 above, provided that you also meet all of these conditions:

There is no word about modify the whole program. If you change a part, everything is GPL, and not only the original parts.

I am no expert, but an GPL expert (I think it was Daniel Mehrmann) told me it would still be GPL. But I am not sure about which version we talked.

Zach Wegner wrote:

Where are these hypothetical non-rewritten code chunks? The UCI handling or the engine AI? Or both?

Both.

Strelka is actually a pretty good place to look for this sort of stuff. It helps to piece together the Rybka code. Did you know that Rybka has the pawn value 3399? Or that Rybka and Fruit use the same easy-move logic with the same margin?

Second question. What is the licence situation for the UCI material? Is that entirely Fabien's work, or did he get all or part of it from someplace else? Where do people get the engine side UCI stuff from?

The UCI protocol is free to use. I suppose that would be considered public domain? I don't know the legal aspect of it. The code to implement it in Fruit however, is copyrighted by Fabien. The engine side of UCI is implemented by reading the protocol specification (at least that's how I did it). I suppose some people might look at another implementation when writing theirs, especially if they are new to chess programming, but the Rybka/Fruit ones are just way too similar IMO.

Chris Whittington wrote: [to Robert Hyatt]

Your code may 'instantly become GPL' but as and when the entire prgram source is rewritten, section by section - when the last section is rewritten, and the code contains no fragments of the original then the code "instantly becomes not GPL".

Zach Wegner wrote:

Your code may 'instantly become GPL' but as and when the entire prgram source is rewritten, section by section - when the last section is rewritten, and the code contains no fragments of the original then the code "instantly becomes not GPL".

But the issue at hand is that Rybka 1.0 might not have rewritten every section.

Chris Whittington wrote:

Your code may 'instantly become GPL' but as and when the entire prgram source is rewritten, section by section - when the last section is rewritten, and the code contains no fragments of the original then the code "instantly becomes not GPL".

But the issue at hand is that Rybka 1.0 might not have rewritten every section.

May I play devil's advocate and ignoramus at the same time?

Let's split this hypothetical Rybka into two conceptual parts. The chess engine and it's UCI support.

Where are these hypothetical non-rewritten code chunks? The UCI handling or the engine AI? Or both?

Second question. What is the licence situation for the UCI material? Is that entirely Fabien's work, or did he get all or part of it from someplace else? Where do people get the engine side UCI stuff from?

Robert Hyatt wrote: [To Chrisw]

Certainly. But if it contains _any_ original fragments, say such as the ones that do UCI output, then it remains GPL until _everything_ is removed. Not just "key parts"...

Robert Hyatt wrote:

Your code may 'instantly become GPL' but as and when the entire prgram source is rewritten, section by section - when the last section is rewritten, and the code contains no fragments of the original then the code "instantly becomes not GPL".

But the issue at hand is that Rybka 1.0 might not have rewritten every section.

May I play devil's advocate and ignoramus at the same time?

Let's split this hypothetical Rybka into two conceptual parts. The chess engine and it's UCI support.

Where are these hypothetical non-rewritten code chunks? The UCI handling or the engine AI? Or both?

Second question. What is the licence situation for the UCI material? Is that entirely Fabien's work, or did he get all or part of it from someplace else? Where do people get the engine side UCI stuff from?

I don't believe that distinction matters in the case of GPL. "grep" has a parser, a regular expression evaluator, etc. I've not seen the GPL apply only to parts of a program like grep...

Chris Whittington wrote:

Your code may 'instantly become GPL' but as and when the entire prgram source is rewritten, section by section - when the last section is rewritten, and the code contains no fragments of the original then the code "instantly becomes not GPL".

But the issue at hand is that Rybka 1.0 might not have rewritten every section.

May I play devil's advocate and ignoramus at the same time?

Let's split this hypothetical Rybka into two conceptual parts. The chess engine and it's UCI support.

Where are these hypothetical non-rewritten code chunks? The UCI handling or the engine AI? Or both?

Second question. What is the licence situation for the UCI material? Is that entirely Fabien's work, or did he get all or part of it from someplace else? Where do people get the engine side UCI stuff from?

I don't believe that distinction matters in the case of GPL. "grep" has a parser, a regular expression evaluator, etc. I've not seen the GPL apply only to parts of a program like grep...

Ok, fine, but hypothetically again ....

Fabien writes Fruit. Fabien produces all the engine AI himself. Fabien also has to do, create or get the UCI handler. Did he write that part all himself, or has he borrowed or used general UCI code, public domain or whatever as part?

I have no idea, but if he saved himself some work and used some PD stuff (or whatever), then sure, he can release Fruit under GPL, but this, in this hypothetical scenario, does not render the (hypothetically externally acquired) UCI stuff covered by the GPL.

So, I ask, what is the licence basis and origin of the UCI handling code?

[Zach Wegner]

Thanks Swami for keeping your cool in all of this. I'm not sure exactly why some of the posts were deleted--it looks like you have quoted my posts in full, as well as the messages that they responded to. I try to take care that I only quote relevant sections of a post.

Anyways, the information that I wanted to post is now here, so it's not a big deal. Keep up the good work.

[George Tsavdaris]

So in my opinion:
- Rybka 1.0 is not a clone of Fruit 2.1, it is somehow different and better
- Rybka 1.0 started as the source code of Fruit 2.1

We have a different opinion what clone means. Starting with the source code would violate the GPL even if every single line is changed. So I would call this cloneing.

But as I stated several times before, it must not be illegal in case the original author agrees.

Alex

Then, what is the purpose of "open source" chess programs at all?
So you can study other's program, but be careful not to study it very well!
Because if you remember too much of it then there's a possibility that you will unintentionally repeat
the program's structure, or parts of code when writing your own program!

You can read other programmer's code just to learn what you must not done in your own...

So open source programs are a good way to "copyright" code and ideas?

No you don't get the idea.
The idea is that you can study the program as well as you want, you can use all the ideas as also all the code you want from the open source program, you can write everything you want containing anything you want from the open source!
There is no copyright of ideas or code. There is no restriction! .....Well there is only one. The simplest:
You should publish the source code of the final program!


So you can do everything you want with the code and the ideas of open source programs under GNU GPL as long as you publish the source code.

[tiger]

So in my opinion:
- Rybka 1.0 is not a clone of Fruit 2.1, it is somehow different and better
- Rybka 1.0 started as the source code of Fruit 2.1

We have a different opinion what clone means. Starting with the source code would violate the GPL even if every single line is changed. So I would call this cloneing.

But as I stated several times before, it must not be illegal in case the original author agrees.

Alex

Then, what is the purpose of "open source" chess programs at all?
So you can study other's program, but be careful not to study it very well!
Because if you remember too much of it then there's a possibility that you will unintentionally repeat
the program's structure, or parts of code when writing your own program!

You can read other programmer's code just to learn what you must not done in your own...

So open source programs are a good way to "copyright" code and ideas?

If Fruit had not been released as open source then we would never have
seen such degenerated debates about cloning here, and stupid and childish
"psychological" dissertations about envy - not envy in a forum about Computer Chess.

The purpose of open source as defended by the GPL is to allow code to be used and re-used and stay "open" without allowing somebody to "close" it again.

Hence the "if you start from GPL code, the result is still GPL".

The purpose of GPL'ed chess programs is to allow people to use and re-use the chess code without allowing somebody to modifiy it and then hide it.

Hence, if you want to write a commercial chess program you must NOT start from an open source one, because by starting from an open source program you explicitely deny yourself the right to hide the source if you publish your program.



// Christophe

[swami]

Thanks Swami for keeping your cool in all of this. I'm not sure exactly why some of the posts were deleted--it looks like you have quoted my posts in full, as well as the messages that they responded to. I try to take care that I only quote relevant sections of a post.

Anyways, the information that I wanted to post is now here, so it's not a big deal. Keep up the good work.

Moderation tools has this split function - If you remove the original post which is offensive, then subsequent replies to it will be gone as well. Really poor mod tools I think.

Also another problem is that a lot of people use direct quotes of someone's texts when they reply to him especially when his text is bound to be deleted...

[rhollay]

No you don't get the idea.
The idea is that you can study the program as well as you want, you can use all the ideas as also all the code you want from the open source program, you can write everything you want containing anything you want from the open source!
There is no copyright of ideas or code. There is no restriction! .....Well there is only one. The simplest:
You should publish the source code of the final program!


So you can do everything you want with the code and the ideas of open source programs under GNU GPL as long as you publish the source code.

No, George. I got the idea very well. I know what GPL is. Just tried to explain why I dislike it.
Of course, it can be very appropriate in other areas of programming when many programmers contribute to develop some useful utility.
But computer chess is mostly about lonely programmers, and releasing code under GPL does not make much sense. At least in my opinion...

[tiger]

No you don't get the idea.
The idea is that you can study the program as well as you want, you can use all the ideas as also all the code you want from the open source program, you can write everything you want containing anything you want from the open source!
There is no copyright of ideas or code. There is no restriction! .....Well there is only one. The simplest:
You should publish the source code of the final program!


So you can do everything you want with the code and the ideas of open source programs under GNU GPL as long as you publish the source code.

No, George. I got the idea very well. I know what GPL is. Just tried to explain why I dislike it.

OK, you have the right to dislike it, and I would certainly not use it myself for my chess engine, but it is the licence under which the source code of Fruit 2.1 has been published.

So GPL is fully relevant to this discussion.



// Christophe