The rumors about Strelka beeing a Rybka clone is still alive

[Eelco de Groot]

Imho, I think the chances of unassembling Rybka code is much, much less than the chances that one of Vas' computers got hacked.

Please then also read Martin Bryant's post about this http://www.talkchess.com/forum/viewtopi ... 68&t=14946

Please also read this other post from Bryan if you have not yet done so or the original post from Vasik Rajlich

http://www.talkchess.com/forum/viewtopi ... 30&t=14970

Please also read some posts from Dann Corbit today

Eelco

I should correct my own last sentence as I only read part of those about reverse engineering but apparently Dann thinks the reverse engineering theory is still very unlikely, from what he has seen in the Strelka sources and based on what is practically possible. I'm not entirely convinced but he is certainly one of the very few persons who has actually seen the code and has much experience with programming and software engineering. The theory of hacking in Vas computer to produce a program like Strelka, I don't think that makes any sense whatsoever.

[James Constance]

Where is Strelka's author in all this? Has he actually stated that he hasn't used Rybka's code? Did he say that when he handed over some source code? I don't hear him.

Just interested...

[M ANSARI]

Vas has made it very clear that Srelka IS using some code of beta Rybka or at least trying to make it look like they are. But apparently with his comment "let them knock their heads off on it" he is not too bothered with that because Rybka 1.0 beta is "ancient".

[matejst]

I am reading this discussion for a few days now and I am quite surprised that it doesn't end.

If I remember well, there were rumours, a few years ago, that Rybka too was a Fruit clone, and Vaclav Rajlich, in an interview found on the Alex Schmidt site, admitted he had used some ideas from the Fruit code. (There is something interesting in the fact that Rybka, although tested previously, has made his way only a few months after Letouzey's work.) But he was obviously not the only one. A lot of engines made a tremendous jump in strength after Fruit (an average of more than 60 elo): HIARCS, Fritz, Loop, among others. Just look at the CSS ratings. The only one not to improve dramatically was SMK's Shredder. Did anybody accuse their authors? No. They found new ideas (in the code of Fruit, perhaps) and they implemented them.

Suddenly there is a young Russian with a new engine: the story is starting all over again, and this time, it is an incredible one. Of course, Osipov has probably read all the Ed Shroeder's articles about programming, and, of course, he reviewed Crafty's, Toga's, Fruit's and Glaurung's code. It is natural that he also tried to discover Rybka's secrets, to have a similar evaluation function, for it is an excellent evaluation function and everybody is doing it too (Christophe Théron has admitted it in this same forum). Does it make him an immoral person, an intellectual thief? One of us has pointed out that no one is starting from the beginning, and that there isn't any engine that is absolutely original. It is so comprehensible.

Then, how could he have stolen Rybka's code? We can see that Vasik Rajlich is doing all he can to protect his code: faking the node count, the size of the -exe, encrypting the exe... If Osipov was German or American, the allegations of some of us could have lead to court: to accuse somebody that he is a (the) hacker that stole code from Vasik Rajlich's computer without proof is a felony. And the premise of the law system in the majority of countries of the world is that someone is innocent until the contrary is proven.

Finally, there are the affirmations of Dann Corbit, Bryan Hofmann and Sergei Markoff – the only one who have indeed seen Strelka’s code, that Strelka is not a clone. Of course, they didn’t see Rybka’s code, but nobody claiming Strelka is a clone has seen Rybka’s code neither. The solution for me is clear: Vasik Rajlich could send his code to Brian Hofmann and Dann Corbit to compare. Why not. (By the way, they could see if Rajlich has changed Fruit search function or has integrated it in his code without changes. ) Osipov, to clear his name, has done it. For me, Vaclav Rajlich's silence about this subject could indicate something else: Osipov has found something Vas wouldn't like to be discovered by others, an idea or the idea that makes Rybka's so strong.

Dann Corbit has made a judicious effort to clear the notions of clone, reverse engineering, what is legal and what is not, and to put an end to this discussion. He is perfectly right: we should be ashamed. Let us hope there will be further versions of Strelka.

[Sylwy]

You are absolutely right !

Sylwy

[Mike S.]

Finding other's "ideas" and implementing them with own code doesn't result in identical or extremely similar output in so many positions.

[Gandalf]

...or the author of Strelka could make a more official statement about the issue. I believe he is the only one who has not truly replied to the question "is Strelka a clone of Rybka?"

[Sylwy]

Better & fair to see Rybka's code for control !

[mjlef]

I doubt any author of a commercial program would release his code, but maybe Vas could release something that does not give away the whole thing. Perhaps header files showing dtat structures, possibly with things renamed. I find even the structure of moves varies a lot between programs. This might give a hint as to how similar programs are.

Also, didn't one of the testing sites (CCRL maybe) have some software to coorelate moves selected between different programs. That could be very insteresting to see as well.

Mark

[Sylwy]

To be a commercial program is not a refuge & excuse in honestity reasons !


Sylwy