About Rybka search info

[Uri Blass]

In my case I studied english at school and later at university I had to understand scientific articles and later I started to write in this forum.

I practically almost never speak in english(writing in english is not speaking) but I use english almost every day.

Uri

[Edward German]

Dear Rolf!

For some time I noticed that you have people here prefer to write and psychology.

Writing in the future, but ask about computer chess (For example, games, analyses, etc.), because that is a computer chess forum.

Thank you!

[Ovyron]

For Rybka 2.3.2a : add +3 to depth.

Does it mean that you have decompiled Rybka 2.3.2a?

[Rolf]

Programming and speaking at English are different things.
I was study english in Moscow physical-technical institute, and it was 20 years ago. After that I have not practice in speaking.

20 years ago, that was before the fall of the Iron Curtain. Nowadays Russians make holidays in Cannes and write chessprograms for Personal Computers! English is the most practical language for sciences and computerchess. Also pilots must speak it because everywhere the flight control is English speaking. Except Switzerland of course where they have too much rests which can cause accidents in the air as you know...

[Osipov Jury]

For Rybka 2.3.2a : add +3 to depth.

Does it mean that you have decompiled Rybka 2.3.2a?

No, a have not decompiled Rybka 2.3.2a. It is very hard work. I only found this simple code in Rybka:

lea edx, [edi-3] ; output: depth-3
push edx
push offset _aInfoDepthD ; "info depth %d\n"
call _sub_52A380
add esp, 8

Or on C-language:

my_printf("info depth %d\n",depth-3);

[Gerd Isenberg]

For Rybka 2.3.2a : add +3 to depth.

Does it mean that you have decompiled Rybka 2.3.2a?

No, a have not decompiled Rybka 2.3.2a. It is very hard work. I only found this simple code in Rybka:

lea edx, [edi-3] ; output: depth-3
push edx
push offset _aInfoDepthD ; "info depth %d\n"
call _sub_52A380
add esp, 8

Or on C-language:

my_printf("info depth %d\n",depth-3);

Hi Jury,

welcome to CCC. Well, with all that aggressive pruning depth-3 might indeed be the better measure

In opposite to Bob Hyatt, I have objections against disassembling commercial programs to extract ideas - even if it was a free pre-commercial beta without explicit license or copyright statement and you were legally right. Strelka becomes open source now, rather than a pure executable as before. I think most program-authors and academics will appropriate that. You seem to become "Robin Hood" of computer chess.

I am interested in your statements, which ideas were adapted or taken from disassembling Rybka 1 by you. But that probably implies another "ethical" dilemma, I already have - to further exploit some of the initial secrets of Rybka.

Like others, I (will) study your sources and there were already and there will further discussions about Strelka in the programming forum of CCC. The material indexing scheme, the pawn-structure indexing scheme and the semantics of the table content. How does your null-move work (multiple in a row)? The delta-pruning (why collecting masks for both side - if you use only the one for side to move later), using 0xFFFFFFF8 instead of ~7 or -8 or even 56 to mask off the file of a square, etc. You are invited to take part in these discussions.

Regards,
Gerd

[playjunior]

For Rybka 2.3.2a : add +3 to depth.

Does it mean that you have decompiled Rybka 2.3.2a?

No, a have not decompiled Rybka 2.3.2a. It is very hard work. I only found this simple code in Rybka:

lea edx, [edi-3] ; output: depth-3
push edx
push offset _aInfoDepthD ; "info depth %d\n"
call _sub_52A380
add esp, 8

Or on C-language:

my_printf("info depth %d\n",depth-3);

Hi Jury,

welcome to CCC. Well, with all that aggressive pruning depth-3 might indeed be the better measure

In opposite to Bob Hyatt, I have objections against disassembling commercial programs to extract ideas - even if it was a free pre-commercial beta without explicit license or copyright statement and you were legally right. Strelka becomes open source now, rather than a pure executable as before. I think most program-authors and academics will appropriate that. You seem to become "Robin Hood" of computer chess.

I am interested in your statements, which ideas were adapted or taken from disassembling Rybka 1 by you. But that probably implies another "ethical" dilemma, I already have - to further exploit some of the initial secrets of Rybka.

Like others, I (will) study your sources and there were already and there will further discussions about Strelka in the programming forum of CCC. The material indexing scheme, the pawn-structure indexing scheme and the semantics of the table content. How does your null-move work (multiple in a row)? The delta-pruning (why collecting masks for both side - if you use only the one for side to move later), using 0xFFFFFFF8 instead of ~7 or -8 or even 56 to mask off the file of a square, etc. You are invited to take part in these discussions.

Regards,
Gerd

Now say that again, slowly, and in Russian

[Jorge Garcia de Andres]

I have a question for you Jury,

There is only one extension in the search:
the check extension in fact, why don't you have put more extensions in the full root function it will have enpowered your engine, try something like this

new_depth = depth - 1;
int desde = MOVE_FROM(move);
piece = Board->square[MOVE_FROM(move)];
to = MOVE_TO(move);

// check extension
if (flag_add_depth || in_check) new_depth++;

// capture extension
int pcapt=Board->square[MOVE_TO(move)];
if (pcapt!=0) new_depth+=1;

// promotion extension
if (MOVE_IS_PROMOTION(move)) new_depth++;

// enpassant extension
if (MOVE_IS_ENPASSANT(move)) new_depth++;

// pawn at 7th extension
if ((desde==WhitePawn) && (to >= 48 || to <= 55)) new_depth++;
if ((desde==BlackPawn) && (to >= 8 || to <= 15)) new_depth++;

// knight at 6th extension
if ((desde==WhiteKnight) && (to >= 40 || to <= 47)) new_depth++;
if ((desde==BlackKnight) && (to >= 16 || to <= 23)) new_depth++;

// rook at 7th extension
if ((desde==WhiteRook) && (to >= 48 || to <= 55)) new_depth++;
if ((desde==BlackRook) && (to >= 8 || to <= 15)) new_depth++;

// queen at 7th extension
if ((desde==WhiteQueen) && (to >= 48 || to <= 55)) new_depth++;
if ((desde==BlackQueen) && (to >= 8 || to <= 15)) new_depth++;

Best Regards

[ozziejoe]

You seem to become "Robin Hood" of computer chess.

I am not sure you meant this seriously? Didn't robin hood steal from rich people who abused power and used poor people like slaves?

in this instance, Vas is probably eeking out a living



This whole situation is morally repugnant. Osipov used his intelligence to steal another person's ideas, and people can't wait to enjoy the fruits of this disgusting act (which I guess is unavoidable.).

If the author of strelka claims that all vas did was duplicate fruit and add a few "trivial tricks", then why hasn't he done the same and created an engine as strong as rybka. Rybka is now over 300 points stronger than fruit 2.1 (and unlike fruit, it is a bitboard engine, for goodness sake.)


And another thing. Decompiling a chess engine and taking away from anothers livelihood is a pathetic way to use ones intelligence: . This activity does not quite rank up their with inventing penicilian, discovering a cure for polio, taking care of a foster child, or even picking up garbage from the street. There is positively no way to take the moral high ground in this situation.


I look forward to the new wave of engines that will be made stronger based on the rybka/strelka code (and not so much on the fruit code which has been available to programmers for a long time.). But please, folks, lets have some character, and remember that the "strelka" code is available to you only through the base acts of osipov.

Let's pay due respect to Vas, not osipov, whose ideas are now spurring you on to create better chess engines.



best
Joseph


[/quote]

[George Tsavdaris]

This whole situation is morally repugnant. Osipov used his intelligence to steal another person's ideas, and people can't wait to enjoy the fruits of this disgusting act (which I guess is unavoidable.).

Can an idea be stolen?
Can we accuse someone for stealing an idea?
Does ideas belong to anyone?
Code yes, but ideas....

Let's pay due respect to Vas, not osipov, whose ideas are now spurring you on to create better chess engines.

Absolutely!