Strelka 2.0B + sources

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IWB
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Re: Strelka 2.0B + sources

Post by IWB »

mjlef wrote:Vas says he is going to release Strelka under his name, since it contains so much reverse engineered (including data tables) from Rybka 1.0 beta:

http://rybkaforum.net/cgi-bin/rybkaforu ... l?tid=3006

This ends the clone debates for sure!
I have to agree!

When is Rybka going to be released under the GPL?

Someone just shoot in his foot!

:lol: :D :P :wink:

Bye
Ingo
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Daniel Mehrmann
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Re: Strelka 2.0B + sources

Post by Daniel Mehrmann »

Alessandro Scotti wrote:From one side we have opinions here at the CCC that Strelka is an obvious "translation" of Fruit, or that it is at least "very, very Fruit like".

On the other hand Vas has posted on the Rybka forum that Strelka is Rybka but he does not "see obvious signs of other code usage" so he claims Strelka as his own!

Surely there is a contradiction between those views? My head is now spinning... :shock:
Well, i believe that strelka has a lot of fruit code inside. I don't know if it was created from a full fruit, but the "author" claimed it.

However, you can see it very easy by just looking on the coding style. How things are written, e.g case sensitive or using"_" or only big letters and so on.
You will find a lot of parts in the sourcecode which doesn't fit in the style of the complete source...

Anyway, Dann Corbit is a very very big disapointment for me and at least he should see that what i explained above. He should no longer be asked in clone cases....sorry

Best,
Daniel
Gerd Isenberg
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Re: Strelka 2.0B + sources

Post by Gerd Isenberg »

Uri Blass wrote: I looked for significant time only at strelka1.8 but did not read part of the files.

I can say that I did not read most of the evaluation of strelka and even now I see there are a lot of numbers for specific bitboards like
0x0004020200000000 so it is not exactly code that is written in a way that it is very easy to understand.

Uri
Hi Uri,

may be you need to write some tool to print bitboards!

Code: Select all

0x0004020200000000

 . . . . . . . .
 . . 1 . . . . .
 . 1 . . . . . .
 . 1 . . . . . .
 . . . . . . . .
 . . . . . . . .
 . . . . . . . .
 . . . . . . . .
Cheers,
Gerd
Alexander Schmidt
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Re: Strelka 2.0B + sources

Post by Alexander Schmidt »

mjlef wrote:And a real genius behind the values for that material correction array.
Let's pretend this values are from Rybka 1, could it result in similaries like descrided here?:

http://talkchess.com/forum/viewtopic.ph ... 91&t=14925

Best,
Alex
Uri Blass
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Re: Strelka 2.0B + sources

Post by Uri Blass »

Daniel Mehrmann wrote:
Alessandro Scotti wrote:From one side we have opinions here at the CCC that Strelka is an obvious "translation" of Fruit, or that it is at least "very, very Fruit like".

On the other hand Vas has posted on the Rybka forum that Strelka is Rybka but he does not "see obvious signs of other code usage" so he claims Strelka as his own!

Surely there is a contradiction between those views? My head is now spinning... :shock:
Well, i believe that strelka has a lot of fruit code inside. I don't know if it was created from a full fruit, but the "author" claimed it.

However, you can see it very easy by just looking on the coding style. How things are written, e.g case sensitive or using"_" or only big letters and so on.
You will find a lot of parts in the sourcecode which doesn't fit in the style of the complete source...

Anyway, Dann Corbit is a very very big disapointment for me and at least he should see that what i explained above. He should no longer be asked in clone cases....sorry

Best,
Daniel
You may also consider Tord as disappointment for you because Tord did not consider strelka to be a clone.

I prefer to assume that a person is not quilty in case of a doubt and some similiarity does not prove that a person is quilty.

I think that strelka has only a small part of fruit code and small part does not prove cloning(otherwise based on the same logic every 2 programs that have i++; inside their code can be considered as clones)

Uri
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Daniel Mehrmann
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Re: Strelka 2.0B + sources

Post by Daniel Mehrmann »

Uri Blass wrote:
Daniel Mehrmann wrote:
Alessandro Scotti wrote:From one side we have opinions here at the CCC that Strelka is an obvious "translation" of Fruit, or that it is at least "very, very Fruit like".

On the other hand Vas has posted on the Rybka forum that Strelka is Rybka but he does not "see obvious signs of other code usage" so he claims Strelka as his own!

Surely there is a contradiction between those views? My head is now spinning... :shock:
Well, i believe that strelka has a lot of fruit code inside. I don't know if it was created from a full fruit, but the "author" claimed it.

However, you can see it very easy by just looking on the coding style. How things are written, e.g case sensitive or using"_" or only big letters and so on.
You will find a lot of parts in the sourcecode which doesn't fit in the style of the complete source...

Anyway, Dann Corbit is a very very big disapointment for me and at least he should see that what i explained above. He should no longer be asked in clone cases....sorry

Best,
Daniel
You may also consider Tord as disappointment for you because Tord did not consider strelka to be a clone.

I prefer to assume that a person is not quilty in case of a doubt and some similiarity does not prove that a person is quilty.

I think that strelka has only a small part of fruit code and small part does not prove cloning(otherwise based on the same logic every 2 programs that have i++; inside their code can be considered as clones)

Uri
Well, let me tell you some things about coding. I don't know if you're working as a professional progammer like me over years in IT/software houses. I worked in big projects (some hundreds of programmer together) and now in a little project (just 30 people). You'll get experince of code style. You'll learn that every programmer has a own signature of coding.

Specialy if it a private one person project, like chessprogramming, the signature is pretty clear. Basicly you're looking to other code and try to understand and write it down in your own signature of code.
In the case of Strelka i found serval lines of code which isn't written in the signature of the other parts.

Back to your arguments i just can repeat that the author claimed he was starting from a full fruit and if i see the code i would agree with him, because as i pointed out above you would write it in your own sginature of code style instead of copying the stuff. That helps you later on to understand your own program better. If you would using other styles and just start to mix your code you'll get a dirty picture.
I know that programmers, this is based on my experince of my work as professional programmer, would avoid this case if it possible anyway.

And keepout Tord please. This is just a dirty try.

Best,
Daniel
Tony

Re: Strelka 2.0B + sources

Post by Tony »

Uri Blass wrote:
Daniel Mehrmann wrote:
Alessandro Scotti wrote:From one side we have opinions here at the CCC that Strelka is an obvious "translation" of Fruit, or that it is at least "very, very Fruit like".

On the other hand Vas has posted on the Rybka forum that Strelka is Rybka but he does not "see obvious signs of other code usage" so he claims Strelka as his own!

Surely there is a contradiction between those views? My head is now spinning... :shock:
Well, i believe that strelka has a lot of fruit code inside. I don't know if it was created from a full fruit, but the "author" claimed it.

However, you can see it very easy by just looking on the coding style. How things are written, e.g case sensitive or using"_" or only big letters and so on.
You will find a lot of parts in the sourcecode which doesn't fit in the style of the complete source...

Anyway, Dann Corbit is a very very big disapointment for me and at least he should see that what i explained above. He should no longer be asked in clone cases....sorry

Best,
Daniel
You may also consider Tord as disappointment for you because Tord did not consider strelka to be a clone.

I prefer to assume that a person is not quilty in case of a doubt and some similiarity does not prove that a person is quilty.

I think that strelka has only a small part of fruit code and small part does not prove cloning(otherwise based on the same logic every 2 programs that have i++; inside their code can be considered as clones)

Uri
Sorry Uri,

but if you think Strelka only contains small parts of Fruit then you're wrong.

It seems you ( and others) are not looking at the functionality of the code, but only at the looks.

The Fruit way

Code: Select all


mob=0

mob+= AttackValue[from-31];
mob+= AttackValue[from-33];
mob+= AttackValue[from-14];
mob+= AttackValue[from-18];

etc

score+=mob*376

is off coarse exactly the same as Strelka's

Code: Select all


BB=AttacksKnight(from) & ~myPieces

mob=PopCount(BB);

score+=mob*376

It just looks different.

If you don't see this, it doesn't matter, just don't bother with your opinion in the clone debate.

If someone steals your bike and paints it, it's still your bike.

The only problem that arises here is that the bike seems to have been stolen before ...

Tony
Guetti

Re: Strelka 2.0B + sources

Post by Guetti »

Gerd Isenberg wrote:
Uri Blass wrote: I looked for significant time only at strelka1.8 but did not read part of the files.

I can say that I did not read most of the evaluation of strelka and even now I see there are a lot of numbers for specific bitboards like
0x0004020200000000 so it is not exactly code that is written in a way that it is very easy to understand.

Uri
Actually, the repeated appearance of the same 64 bit number in hex code is already suspicious, because most programmers who somehow want to still be able to understand the code they wrote at a later time would make something like this:

const int mask_for_this_and_that = 0x0004020200000000;

Other programmers are just to lazy to type in the same number 20+ times. (i.e. 0xffffffffffffffff). But this is just my opinion.
I also wonder, how much fruit code is inside and if it is a lot, why does Vas downplay it?
Last edited by Guetti on Fri Jan 11, 2008 3:29 pm, edited 1 time in total.
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GenoM
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Re: Strelka 2.0B + sources

Post by GenoM »

Tony wrote: Sorry Uri,

but if you think Strelka only contains small parts of Fruit then you're wrong.

Tony
Sorry Tony,

but if you think Strelka contains any code of Fruit then you're wrong. Ask V.Rajlich :) He said Strelka contains disassembled code of Rybka, not of Fruit.

Regards,
Geno
take it easy :)
Alexander Schmidt
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Re: Strelka 2.0B + sources

Post by Alexander Schmidt »

GenoM wrote:but if you think Strelka contains any code of Fruit then you're wrong. Ask V.Rajlich :) He said Strelka contains disassembled code of Rybka, not of Fruit.
And if you ask Youri Osipov, then Strelka is based on Fruit and has parts of Rybka inside. And he also said, he thinks Vasik Rajlich has done the same. Thats all.

Alex