Fabien's open letter to the community

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Matthias Gemuh
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Re: Fabien's open letter to the community

Post by Matthias Gemuh »

JuLieN wrote:@HGM
Allow me to be a bit parodic, and don't take it bad. :)

It is really remarkable how everyone tries to twist facts to confirm their own point of view. Are they unable to read, or do they suppose that others are not able to read, so they can get away with posting any nonsense they want? :roll:

As a service to the dyslectic, I repeat the qoute of Fabien with some bold-face highlighting of mine:
Fabien Letouzey wrote:The short answer was "no", it was not a verbatim copy of the source code. All the code had been typed (can't say "designed" though, see below) by an individual. So legally there was no issue that I knew of. It was however a whole re-write (copy with different words if you like, similar to a translation) of the algorithms. Not just an extraction of a couple of ideas as is common, and normal.
HGM totally missed seeing that. :D :D :D
My engine was quite strong till I added knowledge to it.
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AdminX
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Re: Fabien's open letter to the community

Post by AdminX »

Ovyron wrote:It's going to be a difficult case, Vas never saved his sources codes, he doesn't have the Rybka 3 one, so I'm sure he doesn't have the code of Rybka 1.1 or 2.0, all the investigations would need to be done as reverse engineered code.

It was unfortunate that Vas claimed Strelka's code as his own, since later it was found out that it had significant parts of Fruit.

As about the ply and node count obfuscations, they have been explained at Rybka forum, 3 plies are added to normalize the count relative to other engines, as earlier plies are "thinner" and don't fulfill their definition of ply, nodes are recalculated so they can be used to compare different hardware, i.e. higher nodes must mean higher strength at all times, unlike other engines that with hyperthreading show higher node count but play weaker.
Question: If Vas LOST Rybka 3 Sources, Then how the Hell did he write Rybka 4 so fast. That is a hell of allot of code for a very strong program.
Last edited by AdminX on Mon Jan 24, 2011 11:25 am, edited 2 times in total.
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Chan Rasjid
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Re: Fabien's open letter to the community

Post by Chan Rasjid »

JuLieN wrote:@HGM
Allow me to be a bit parodic, and don't take it bad. :)

It is really remarkable how everyone tries to twist facts to confirm their own point of view. Are they unable to read, or do they suppose that others are not able to read, so they can get away with posting any nonsense they want? :roll:

As a service to the dyslectic, I repeat the qoute of Fabien with some bold-face highlighting of mine:
Fabien Letouzey wrote:The short answer was "no", it was not a verbatim copy of the source code. All the code had been typed (can't say "designed" though, see below) by an individual. So legally there was no issue that I knew of. It was however a whole re-write (copy with different words if you like, similar to a translation) of the algorithms. Not just an extraction of a couple of ideas as is common, and normal.
It seems derivative under GPL is not only about 'cut_and_paste', but includes translation of the source code (including in a different computer language). So Strelka translating Fruit to bitboard has a legal issue if not GPL'ed. Any other program getting too close to Strelka could also legally be a derivative.

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bhlangonijr
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Re: Fabien's open letter to the community

Post by bhlangonijr »

hgm wrote:It is really remarkable how everyone tries to twist facts to confirm their own point of view. Are they unable to read, or do they suppose that others are not able to read, so they can get away with posting any nonsense they want? :roll:

As a service to the dyslectic, I repeat the qoute of Fabien with some bold-face highlighting of mine:
Fabien Letouzey wrote:The short answer was "no", it was not a verbatim copy of the source code. All the code had been typed (can't say "designed" though, see below) by an individual. So legally there was no issue that I knew of. It was however a whole re-write (copy with different words if you like, similar to a translation) of the algorithms. Not just an extraction of a couple of ideas as is common, and normal.
HGM, please correct me if I am mistaken but if we do some logic progression it seems Fabien's open letter implies a lot of things:

1) AFAIK Strelka is a product of reverse engineering therefore it would never be a verbatim copy of the source of Rybka - Even less a verbatim copy of Fruit's source as it is, supposing it is contained in the original Rybka 1.0 source code;
2) The fact Strelka is pretty equivalent to Fruit's algorithms strongly suggests that the original Rybka's C source contained Fruit's algorithms, and most probably as a verbatim copy of Fruit (e.g Copy & Paste);
3) Hypothetically if one use a tool to rename all constants, variables and functions of a GPLed program and get a completely re-rewritten program, even then it constitutes a GPL violation;
4) Even if it is crystal clear for Fabien that Rybka is derived from his work he won't state publicly "Rybka is a clone" or whatever. I personally think, by reading his open letter, that Fabien firmly believes Rybka is derived from his work (after waking up from his hibernation) and now he wants to clean up all this mess.
Gian-Carlo Pascutto
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Re: Fabien's open letter to the community

Post by Gian-Carlo Pascutto »

hgm wrote: I don't understand the fuss. What Fabien _believes_ is of zero and void relevance, isn't it? The Strelka code is pubic. The Fruit code is public. Everyone that can read can _see_ if one is derived from the other, and if that is a copyright violation or not. Or is everyoone here a complete dyslectic, all worshippers of Fabien as the only person in this Universe that knows how to read? :shock:
The issue is, Vasik could (I'm not saying he is!) violate the GPL all he wants, if the alledged original copyright holder doesn't care, nothing can possibily ever happen.

But it seems the original copyright holder DOES CARE. What he believes certainly matters; it's the only way something can happen on the legal front.
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hgm
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Re: Fabien's open letter to the community

Post by hgm »

JuLieN wrote:
Fabien Letouzey wrote:The short answer was "no", it was not a verbatim copy of the source code. All the code had been typed (can't say "designed" though, see below) by an individual. So legally there was no issue that I knew of. It was however a whole re-write (copy with different words if you like, similar to a translation) of the algorithms. Not just an extraction of a couple of ideas as is common, and normal.
Well, that is not a violation of the GPL, well? So why do you think it is of any relevance whatsoever?

And it still does not say anything that anyone wih eyes could not have known for years...
Uri Blass
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Re: Fabien's open letter to the community

Post by Uri Blass »

Gian-Carlo Pascutto wrote:
hgm wrote: I don't understand the fuss. What Fabien _believes_ is of zero and void relevance, isn't it? The Strelka code is pubic. The Fruit code is public. Everyone that can read can _see_ if one is derived from the other, and if that is a copyright violation or not. Or is everyoone here a complete dyslectic, all worshippers of Fabien as the only person in this Universe that knows how to read? :shock:
The issue is, Vasik could (I'm not saying he is!) violate the GPL all he wants, if the alledged original copyright holder doesn't care, nothing can possibily ever happen.

But it seems the original copyright holder DOES CARE. What he believes certainly matters; it's the only way something can happen on the legal front.
suppose that vasik violated the GPL with rybka1 beta(I also do not claim that it happened).

What is the consequence or what legal steps can Fabien do against him?
He cannot force him to release the code of rybka1 beta in case that Vas simply lost the code.

He also cannot force Vas to release his latest rybka because there is no proof that Vasik broke the GPL of fruit with the latest rybka.

Can he ask court to force Vas to give him money?
If yes how much?

I am not a lawyer so I do not know.
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hgm
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Re: Fabien's open letter to the community

Post by hgm »

bhlangonijr wrote:HGM, please correct me if I am mistaken but if we do some logic progression it seems Fabien's open letter implies a lot of things:

1) AFAIK Strelka is a product of reverse engineering therefore it would never be a verbatim copy of the source of Rybka - Even less a verbatim copy of Fruit's source as it is, supposing it is contained in the original Rybka 1.0 source code;
2) The fact Strelka is pretty equivalent to Fruit's algorithms strongly suggests that the original Rybka's C source contained Fruit's algorithms, and most probably as a verbatim copy of Fruit (e.g Copy & Paste);
3) Hypothetically if one use a tool to rename all constants, variables and functions of a GPLed program and get a completely re-rewritten program, even then it constitutes a GPL violation;
4) Even if it is crystal clear for Fabien that Rybka is derived from his work he won't state publicly "Rybka is a clone" or whatever. I personally think, by reading his open letter, that Fabien firmly believes Rybka is derived from his work (after waking up from his hibernation) and now he wants to clean up all this mess.
1) Yeah, so? Fabien did not tell anything that was not obvious even without knowing either the Strelka or the Fruit code?
2) Pure speculation. It can just as easily be a rewrite already in Rybka. You cannot know that, Fabien cannot know that without decompiling Rybka, or compiling Fruit with the same compiler as Rybka, and comparng the binaries. And neither of you have done that.
3) Indeed, merely renaming symbols would not be enough to wrestle a program out from under its copyrights, and there would be a strong legal case. Which Fabien dd just deny...
4) But he _says_ there is no legal case. Of course one can think that this is not very relevant, because it is only what he _says_, and he of course must _believe_ something completely different, because that is what you _believe_. So the fact that he directly contradicts what you believe must be very strong _proof_ that you have been right all along about this... :lol:
rbarreira
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Re: Fabien's open letter to the community

Post by rbarreira »

Am I to believe that a professional developer loses the sources of all the previous versions? No version control to keep old versions? No backups, nothing?

I don't really care about the Clone Wars, but as a developer it's amusing to see claims like these, which are either lies or just pure stupidity.
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Laskos
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Re: Fabien's open letter to the community

Post by Laskos »

Uri Blass wrote: The information that I can provide is that
Strelka1.8 is designed to be as similiar as possible to rybka1 beta.
There are positions when they have the same fail high and fail low and when I analyze blocked positions I get almost the same data(evaluation may be different by 0.01 pawns or something like that but they have the same fail high and fail low when the only difference is that free source strelka needs to get depth that is bigger by 2 plies).

strelka1.8 and Rybka1 beta even share the same bug that no program that I know has(not a bug that fruit has).

Uri
Using Don's similarity test, Strelka 1.8 is closer to Rybka 1.0 than the statistical noise, therefore Strelka 1.8 is an exact clone of Rybka 1.0 within error margins.

Image

In the graph, the distance to the common ancestor denotes the degree of relatedness.

Also, Rybka 1.0 seems more related to Fruit 2.1 than Ippo family and Houdini are to Rybka 3.

Kai