Rybka 1.0 vs. Strelka

[kranium]

Next, (and by the way, I didn't point out the claim by Vas, CT quoted it and suddenly a "warning light" started blinking as I had just not given this much thought) we do not have the source of R1. But we have a direct statement by Vas that Strelka was a copy of R1, that the source for Strelka was written by reverse-engineering the assembly language in the Rybka 1 executable. And he then claimed that "strelka is my code, and I will now distribute it as such." So we have a direct tie from strelka to Rybka.

Finally, a few have started to compare strelka to fruit, and have found marked similarities, and lots of identical code that is shared between both. So this establishes a link from strelka to fruit.

So we end up with a direct connection from fruit -> strelka -> rybka 1, with the probable connection of Rybka 1 -> Rybka 2 -> Rybka 3.

yes...

and a while back an extremely thorough line by line binary comparison of the Stelka 2.0 and Rybka 1.0 executables was conducted by (a group of software engineers) - led by Rick Fadden, who concluded the two binaries were 100% 'identical'.

http://64.68.157.89/forum/viewtopic.php ... bka+stelka

it seems clear to me that this document, when used in conjunction with fruit 2.1 -> strelka 2.0 source code comparison bolsters the argument considerably.

oh yes and there's more here:
http://64.68.157.89/forum/viewtopic.php ... ht=strelka

in brief, rick's conclusions were:

(strelka 2.0 binary to rybka 1.0 binary)
Big Picture Summary: All of the code above matches, all of the code below matches, everything matches (with some exception, but the amount of material that matches exactly is stunning).

(strelka 2.0 source code to rybka 1.0 binary)
Keep in mind that I have stepped through all of the chess logic in Strelka and for each single line of C++ I see the exact same calculation in the Rybka 1.0 Beta X86 instructions. Everything exactly matches.

[Oscar L]

Just curiosity


Are you in touch with Fabien Letouzey?

Is it true that he is developing a new engine?



Regards

[kranium]

Just curiosity

Are you in touch with Fabien Letouzey?

Is it true that he is developing a new engine?

Regards

Hi Oscar...
if you're addressing the question to me, no, i'm not in touch with him.
i believe there is a team, including programmer Ryan Benitez (or maybe Ryan by himself, not sure), that are working on Fruit, and making great progress from what i can see. But a new engine...i have no idea, you'd have to contact one of them.

Maybe if you post the question as a new topic someone would have info for you... this is probably not the best place.

Norm

[Dirt]

The GPL is a private, civil law contract. If a program is developed from the relevent source, any contract enforcement is between the original owner (Fabien) and the developer.

It's under civil law. Not criminal law. There is not and there cannot be any possibility of a criminal law breach.

I'm not a lawyer, and what understanding I have is limited to US law, but I think this is mostly wrong. The GPL is a license not a contract. This is legally very important, as both parties generally have to agree to a contract, but a conditional license can be granted unilaterally. Copying without a license is therefor a copyright violation and not a contract violation, which means there could be statutory damages in excess of the actual damages that could be sued for under contract law.

There is such a thing as criminal copyright infringement. I do doubt it could come into play in this situation.

[bob]

Hi Chris,

[snip]

Fabien says he has no problem.

Where did Fabien say it? This is of key importance in the whole issue.

Enrique

It's a bit convoluted, but the argument of the "Rybka 1.0 beta might be a clone camp" goes like this ...

Strelka is a reproduction of Rybka 1.0 beta.
Strelka resembles Fruit at a programming level
Therefore Rybka 1.0 resembles Fruit.

The "Rybka 1.0 beta protection society" argues:
Fabian has no worries with Strelka.
If other side wants to argue Strelka = Fruit
then Fabian by extension also has no problems with Rybka.


Bob wrote:
Didn't Vas clearly post "Strelka is a reproduction of Rybka 1.0 and I am claiming it as my own code now"??? I saw that specific comment (probably not those exact words, but semantically _identical_ posted by him when the Strelka / clone issue first broke.

Dan Corbit wrote:
This is what Fabian said about Strelka:
"No worries as far as I am concerned.
Ideas are not a legal property.
The code was rewritten so it's OK with me.
Tournament organisers might think differently.
I cannot say a definite yes or no ..."

Some programmers found code similarities between Strelka and Fruit; Vasik said that Strelka was R1 beta; Fabien told Corbit that he didn’t mind about Strelka. When was all that?

I’m asking because I would like to know why these accusations take place now and not in the old times of Rybka 1 beta. And whether they are related to other accusations here last week about Rybka giving R2 for free and not showing the true node count. I’m not saying it’s a campaign, but it might very well look like it, with these three simultaneous accusations against Rybka just before China 2008 and immediately after the huge lead of Rybka 3.

By the way, when Vasik said that Strelka was R1 beta, was he referring to the whole program or to parts of it? If to parts of it, the whole accusing syllogism (part of Str = Fr, part of Ry = Str, therefore Ry = Fr) is false, because Strelka could have copied parts of Rybka code different than Fruit. Possible? I'm asking you as programmer. I'm lay.

As for your "Tournament organizers might think differently", Rybka 3.x will play in China, not R1 beta, so I don’t see on which grounds the organizers could object.

Enrique

It is not much of a stretch to believe that R2 has much of the same source as R1. And that R3 has much of the same source as R2. So _if_ R1 is a partial or complete copy of fruit, R1 is automatically GPL code. And unless R2 was 100% rewritten, R2 would also be GPL. Ditto for R3.

So we end up with a direct connection from fruit -> strelka -> rybka 1, with the probable connection of Rybka 1 -> Rybka 2 -> Rybka 3.

I have not been involved in discovering this, I have followed the discussions, and have stated several times that based on the evidence that has been presented, things appear to be a bit off-color. Since the Rybka group are offering no arguments or evidence to the contrary, it would be hard to draw any other conclusion.

You say "_if_" above, and then go on to "probable connection".

Methinks you should be extremely cautious before alleging a connection between R1->R2->R3 and then asserting a problem with R1.

Do you have evidence that R3 has R1 beta code contained within? If not, the comments above are exceptionally dangerous.

Did you read what I wrote? I wrote (and rewrote) "blitz" 7 times. _major_ changes. But big chunks of code were reused. Who needs a new opening book format, new PGN parser, new move input/output code, etc? I then rewrote Cray Blitz three times. Major changes. 20,000 lines of assembly language added. over a Period of several years. Yet each had at least 60% of code re-used. I have rewritten Crafty 3-4 times as it was time to clean up and re-do. And again, 50+ % (if not more) of the code was kept. The most recent rewrite where I eliminated all duplicate code was a big change, but tons of reuse.

I wrote above "It is not much of a stretch to believe that most of R1 source was retained and used in R2, and that most of R2 would be reused in creating R3." I see _zero_ danger there and if someone would want to challenge me on it, suits me. The university has a team of lawyers to handle such nonsense. I did not say "absolutely, R3 contains part of R1". I said "it most likely does" and I'd stake my software engineering reputation on such a statement any day of the week... The probability is _HIGH_ that if R1 contains GPL code, R2 and R3 also do. But even if not, if R1 contains GPL code, that could be a significant legal issue for someone if the FSF folks get interested.

[bob]

I'm not a programmer and so all this code being produced means little to me.
However, from what I've read, it seems that no matter what is said, there will still be disagreement amongst more knowledgeable people than myself over what constitutes absolute proof of anything untoward.
What I would be interested in is what those like yourself, Bob and Zach are therefore trying to achieve. What exactly is it that you want as the end outcome?

Regards, Graham.

Hyatt, Wegner, Schmidt, Donninger, Cozzie, Theron, Korshunov and other russian programmers are on the same side. Mehrmann and Benitez have had some suspicions too. Who's on the other side, Graham? From these 'more knowledgeable than yourself' people?
Are you expecting God come down and said the ultimate truth?

Well I'm an ex-programmer, but more to the point I ran a business based on games AI, and my view is that Vas has done nothing wrong.

1. The alleged connection with Strelka is completely irrelevent to Fruit

2. That version 1 beta was not commercial and I doubt it any different to the 500 or more, whatever the number, of "amateur" programs that have suddenly been created in the wake of published free source codes.

3. The Fruit programmer who owns the GPL licence says he has no problems with Rybka in any form, beta, 1, 2, 3

4. If there ever was any Fruit code in beta 1, then it is an absolute guarantee that future commercial versions created will have removed every last bit of it.

5. If Vas looked at Crafty, TSCP, Fruit or anything else he did no more and no less than any other current programmer. If he used bits and pieces of other programs to get his version up and running he will have done no different to any other programmer. Or is anybody seriously suggesting all those amateurs started absolutely from scratch? Hahaha.

I started from absolute scratch in 1968. I again started from absolute scratch in 1994 when I threw out the FORTRAN/Assembly Cray Blitz program, and started Crafty using C. In 1994 there were _no_ open source bitboard programs.

So yes, at least _one_ started from scratch. I can't speak for others. But something tells me I am not that unique.

All that counts now from his commercial business point of view and that of his publisher is that the R3 version is squeaky clean. Which it is, obviously.

What is _that_ based on, since we have seen _no_ statement from the Rybka team relative to this? Nobody has said that there is 100% certainty of anything, and that would include either innocence or guilt here. There is a lot of circumstantial data that certainly suggests a strong linkage however. So what have I missed that suggests the it is "obviously squeaky clean"???

For those people who complain that their source is used by commercials, or that other source is used by commercials (and by used, I mean read, rewritten, learnt from, whatever) the answer is easy. Don't publish your sources over the internet.

Not everyone is guilty of plagiarism/copyright infringement/etc. Some of us actually like to exchange ideas, and for me, an idea is more easily expressed in source code than in any other way.

[Olivier Deville]

I'm not a programmer and so all this code being produced means little to me.
However, from what I've read, it seems that no matter what is said, there will still be disagreement amongst more knowledgeable people than myself over what constitutes absolute proof of anything untoward.
What I would be interested in is what those like yourself, Bob and Zach are therefore trying to achieve. What exactly is it that you want as the end outcome?

Regards, Graham.

Hyatt, Wegner, Schmidt, Donninger, Cozzie, Theron, Korshunov and other russian programmers are on the same side. Mehrmann and Benitez have had some suspicions too. Who's on the other side, Graham? From these 'more knowledgeable than yourself' people?
Are you expecting God come down and said the ultimate truth?

Well I'm an ex-programmer, but more to the point I ran a business based on games AI, and my view is that Vas has done nothing wrong.

1. The alleged connection with Strelka is completely irrelevent to Fruit

2. That version 1 beta was not commercial and I doubt it any different to the 500 or more, whatever the number, of "amateur" programs that have suddenly been created in the wake of published free source codes.

3. The Fruit programmer who owns the GPL licence says he has no problems with Rybka in any form, beta, 1, 2, 3

4. If there ever was any Fruit code in beta 1, then it is an absolute guarantee that future commercial versions created will have removed every last bit of it.

5. If Vas looked at Crafty, TSCP, Fruit or anything else he did no more and no less than any other current programmer. If he used bits and pieces of other programs to get his version up and running he will have done no different to any other programmer. Or is anybody seriously suggesting all those amateurs started absolutely from scratch? Hahaha.

All that counts now from his commercial business point of view and that of his publisher is that the R3 version is squeaky clean. Which it is, obviously.

For those people who complain that their source is used by commercials, or that other source is used by commercials (and by used, I mean read, rewritten, learnt from, whatever) the answer is easy. Don't publish your sources over the internet.

I am very shocked to read such general accusations from a moderator of this forum. Is the charter gone ?

Olivier

[Graham Banks]

I think the thing that disturbs me most about all this is the timing.
It certainly gives the appearance that because Vas released Rybka 2.2 as a free engine, this is payback from a lot of pissed off programmers.

[Tony]

I'm not a programmer and so all this code being produced means little to me.
However, from what I've read, it seems that no matter what is said, there will still be disagreement amongst more knowledgeable people than myself over what constitutes absolute proof of anything untoward.
What I would be interested in is what those like yourself, Bob and Zach are therefore trying to achieve. What exactly is it that you want as the end outcome?

Regards, Graham.

Hyatt, Wegner, Schmidt, Donninger, Cozzie, Theron, Korshunov and other russian programmers are on the same side. Mehrmann and Benitez have had some suspicions too. Who's on the other side, Graham? From these 'more knowledgeable than yourself' people?
Are you expecting God come down and said the ultimate truth?

Well I'm an ex-programmer, but more to the point I ran a business based on games AI, and my view is that Vas has done nothing wrong.

1. The alleged connection with Strelka is completely irrelevent to Fruit

2. That version 1 beta was not commercial and I doubt it any different to the 500 or more, whatever the number, of "amateur" programs that have suddenly been created in the wake of published free source codes.

3. The Fruit programmer who owns the GPL licence says he has no problems with Rybka in any form, beta, 1, 2, 3

4. If there ever was any Fruit code in beta 1, then it is an absolute guarantee that future commercial versions created will have removed every last bit of it.

5. If Vas looked at Crafty, TSCP, Fruit or anything else he did no more and no less than any other current programmer. If he used bits and pieces of other programs to get his version up and running he will have done no different to any other programmer. Or is anybody seriously suggesting all those amateurs started absolutely from scratch? Hahaha.

.

1. The connection is neither alleged nor irrelevent.
2. irrelevent
3. irrelevent
4. irrelevent
5. I'm not sure if you are talking about the programmers in this forum where you choose the be a moderator, or about the programmers in your company.
But if it's the first, then I know you're wrong and I really dislike your accusation. I'm not saying it hasn't happened, but you're suggesting everybody does, which isn't true.

Tony

[Terry McCracken]

I think the thing that disturbs me most about all this is the timing.
It certainly gives the appearance that because Vas released Rybka 2.2 as a free engine, this is payback from a lot of pissed off programmers.

I don't see this is the case at all. Even if it were it wouldn't alter the facts one iota.

I want to see Rybka continue, but I don't want others violating the GPL.

Christophe wasn't kidding that he could write a program as good or better than Rybka 3 if he violated the rules.

We don't want to see a repeat of it! I'm concerned if people do attack the programers enough we might!!