Questions for Vas

[Michael J Fitch]

Anyway, I found xor castle state more natural, even with your mentioned initialization issues. You can not get a castle right back in make move. Thus a one bit in the xor sum of the states implies appropriate castle rights lost in make move and is therefor sufficient as index. Probably I am a bit biased with my quad-bitboard color flipper

Interesting. I still think it is rather unnatural, but I can see your reasoning. Of course, Fabien also seemed to favor that method. It does seem to me to be a rather unconventional way, though.

I appreciate your courage, fairness and reasoning!

Believe me Gerd, the feeling is mutual. This forum is a very difficult place to conduct any sort of an investigation. We have tried to make it a public process, so that as many objective opinions can be gathered and so that we can get as much information public as quickly as possible. This seemed to backfire rather badly.

((( As well it should !!
Why did you and your cronies feel the need to bring your public opinion investigation to this forum as quickly as possible?
Wouldn't a completely thorough investigation, presenting ALL evidence of wrong doing-after you had ALL the facts of wrong doing be more acceptable than if's-and's-but's-maybe's-couldn't possible happen- blah blah blah?
I know the post is Question for Vas, but i believe he answered this question a long time ago.I copied this from another post-maybe you've read it-maybe not-but it speaks volumes to me as far as the development of Rybka-which got alot of help/IDEAS from alot of people, as stated by it's author/programmer !!!

Special Thanks

I hesitate to include this section because I know I'll forget people who have been helpful in this project, but (with advance apologies to the omitted) here goes:

Robert Hyatt - For Crafty. There is nothing like an open source program for passing knowledge to the next generation.
Fabien Letouzey - For Fruit, which shattered a number of computer chess myths, demonstrated several interesting ideas, and made even the densest of us aware of fail-low pruning.
Tord Romstad - For making Fabien aware of fail-low pruning , and more seriously for sharing in every way possible his considerable knowledge.
Eugene Nalimov - For his cryptic but somehow fully functional endgame tablebase access code.
Uri Blass, Gerd Isenberg, Dieter Burssner, Vincent Diepeveen, Raschid Chan, Anthony Cozzie, Mridul M* , Thomas Gaksch, Peter Berger, Sandro Necchi, Ed Shroeder, Amir Ban, Christophe Theron and every one else, past and present, on the computer chess club: For sharing their computer chess knowledge despite the fact that in principle computer chess is a competitive field.
Heinz van Kempen, Guenther Simon, Olivier Deville, Sergio Martinez, Claude Dubois: for testing early versions of Rybka despite countless bugs and annoying problems.
Alex Dumov, Gabriel Luca: for helping a Windows newbie get up to around half-speed without excessive derision (or at least open derision )
and Iweta: for being great! and a pretty good Rybka tester and web master to boot

Happy testing, and best chess regards,
Vasik Rajlich
Budapest Hungary
December 4, 2005

((( my 2 cents, which amounts to nothing given i don't know crap about programming-but i love chess !!!

Regards
Michael


Instead of calm, objective discussion, as is happening right here, there is a huge amount of noise surrounding motives etc. in which the good stuff can easily be drowned out.

Your posts are both informative and unbiased. You present the arguments for the other side without taking a side at all. Though you have made very few posts in this matter compared to most, your contribution is invaluable.

Thank you for your kind words, Gerd. I wish you well.

Regards,
Zach

[irvstein1]

no matter what you find at the end of the day rybka will still be rated 200 elo stronger than any engine here . so the only way to be fair is if vas allows a couple witch hunters to have some of his rybka 3 code because none of the people here are capable to catch him otherwise . fruit cant catch him i find that very strange dont you ? i also had a original thought , if people spent more time fixing there spagetti code maybe things would be more even , just a thought .

[chrisw]

This page sent to Vas by email, 11:00 am UK time, Thursday 28th August 2008

He is free to either ignore it, respond by email for passing back here, replying here himself or replying in Rybka forum.

Frankly I find the questions not sufficiently worked up nor presented properly enough to warrant any form of answer. The promised web page does not exist, mentions of Strelka are irrelevent, there's no side by side listings of anything, there are references to external stuff not actually shown how to find it, it states this is not a complete list and there are other (unpublished) issues in contravention to what was asked for, namely a complete list of concerns. However, as requested, I sent it.

EDIT: please keep this thread clean. I'd like to only have specific questions about low level similarities between Rybka and Fruit, and possibly answers from Vas. No need to start another flamewar here.

Vas,

You agreed to answer any questions about similarities between Rybka 1.0 and Fruit. I am glad that you have agreed to do such, and I hope you take the time to answer each of the concerns that I and others have.

This list of similarities between Rybka 1.0 and Fruit was compiled in the past day or so. It's by no means complete, and there are other issues that I've found that I haven't totally verified yet. Each item in this list may be a small similarity that other engines also have, but the idea is to show how many of them are. At some point it will have to be decided whether it all is just a coincidence or not. For those that ask for proof, I'm going to try to set up a web page with snippets of disassembly compared to the Fruit code for each claim made here. Any assistance that anyone has in doing this would be greatly appreciated. It would also help to point out low-level similarities between Strelka and Fruit. These would be verified against Rybka 1.0 by myself or someone else before posting.

I will add, Vas, that some have questioned our motives in presenting these questions. I believe that Rybka started its life as Fruit. I don't wish that you stop. You have obviously done some amazing things with Rybka, and I want them to continue just for the sake of advancement. I just want everyone to play by the rules. If you started with Fruit, there's no problem with that, you just need to be forthcoming about it and abide by the license. I'm not even interested in the legal aspect of all this, that would be for others to handle if necessary.

COMMAND INTERPRETER:
--The UCI 'go' parser is virtually identical (as shown by Rick Fadden), including the time control code

SEARCH:
--Does not use fractional extensions
--In the root function, for initializing the search, the order of steps is:
Generate legal moves
Setjmp
Limit depth if num_moves == 1 to 4
Increment hash age
Reset killers
Reset history
Look up hash move
Score and sort moves
--Use identical easy move logic: if (depth == 1 && best_score > second_best + 150) easy=true;
--both use flags in the root function bad_1 and bad_2

EVAL:
--Piece square tables are of the form [12][64][2], where the last entry is game stage

TRANS:
--Stores both a minimum and maximum bound in the hash table, and depths for both
--Stores only 32 bits of the hash key
--Stores a quantity called "move depth"
--For the replacement scheme, a value is calculated that is trans_age[entry] - depth, where trans_age contains the difference of the current date and the entry's date mod DateSize (4 in Rybka, 16 in Fruit). This is multiplied by 256. In Rybka, the table has the values already multiplied by 256, and in Fruit, it is multiplied on the fly.
--Both use a bucket system with 4 entries

BOARD REPRESENTATION:
--Uses an "undo_t" to store moves that it made, which are only kept on the system stack, not in regular memory.
--Only game history stored is a stack of hashkeys
--The index of this game history is stored as an int, not a pointer
--Two values, "opening" and "endgame" are stored in the board, containing sums of piece square tables
--The masks for hashing castling status are WK=1, WQ=2, BK=4, BQ=8
--For hashing of castling status, the hashkey is updated by CastleHash[oldflags ^ newflags], rather than the more natural CastleHash[oldflags] ^ CastleHash[newflags]
--Both have separate make_null and undo_null functions

[chrisw]

This page sent to Vas by email, 11:00 am UK time, Thursday 28th August 2008

He is free to either ignore it, respond by email for passing back here, replying here himself or replying in Rybka forum.

Frankly I find the questions not sufficiently worked up nor presented properly enough to warrant any form of answer.

I don't really understand why you sent this very page and only this one and only now. This is a relatively old page, not updated for several days. New material has been published in several threads since. Even side-by-side comparisons. Where are they?

Don't you understand? Oh dear. Well, read the threads.

chrisw wrote:
well, whenever so far I got told to go get a link somewhere, I apparently came back with the wrong one and got flamed, so, to avoid that, why don't you block copy your text question(s) into this thread and I'll block copy it to Vas by email?

Zach wrote:
http://64.68.157.89/forum/viewtopic.php?t=23249&start=0

That's all for now. All I ask is that these answers are answered in public, not through email.

Perhaps I sent it because I was asked to send it by the author, Zach?

Perhaps I didn't send anything before because I was banned by the author from communicating his stuff to Vas before now?

Irritating to have to spell it out for you.

Anything else you'ld like to know?

[chrisw]

Anything else you'ld like to know?

No, thanks. Why would I ask new questions when you wouldn't answer the old ones?
There is nothing in that thread telling you you should send incomplete data.

What a load of tosh.

I asked what to send, Zach pointed to a post.

If I cut bits from it, you'll accuse me of censoring

If I add bits to it, you'll tell me I wasn't asked to do that.

If I send it as it is, you tell me some other nonsense. Why don't I also send so and so else. As if you were the technical question compiler. Are you? No.

I sent what I was asked to send, no more and no less.

And, if your 'side' is so concerned, why doesn't it send the questions itself? Doh!

[kranium]

Anything else you'ld like to know?

No, thanks. Why would I ask new questions when you wouldn't answer the old ones?
There is nothing in that thread telling you you should send incomplete data.

What a load of tosh.

I asked what to send, Zach pointed to a post.

If I cut bits from it, you'll accuse me of censoring

If I add bits to it, you'll tell me I wasn't asked to do that.

If I send it as it is, you tell me some other nonsense. Why don't I also send so and so else. As if you were the technical question compiler. Are you? No.

I sent what I was asked to send, no more and no less.

And, if your 'side' is so concerned, why doesn't it send the questions itself? Doh!

What a load of tosh Chris...

What i do see (and have seen consistently) is you suggesting to him what should be done and how.

Why are you insisting on sitting in the middle and acting like a communication conduit?

if you insist on copying info/posts to Vas privately, fine. that is your right.

But Zach is perfectly capable of communicating with Vas on his own, and has already done so at length at the rybka forum.

as you suggest, we'll be more than happy to send the questions ourselves...please allow Zach to present his own case.

[bnemias]

It's funny how Chris continues as Vas' personal communication conduit to this forum. (Good word, btw)

Again, it's unbelievable that people take it upon themselves to feel insulted on Vas' behalf. There's no hint that he's even offended.

[GenoM]

I don't believe Rajlich feels offended.
I think he is pretty logical and objective man.
There was no basis for such a feelings.
It was all about facts of its program origins not about him.

[chrisw]

There you go again. Wilful untruth and false accusation gets to be your leitmotif, does it not? I suppose you think you can do what you want, invent what you want, accuse what you want, publish other peoples material as you want - and then "apologise"?

Not interested in any more of your worthless apologies.

Can you read, before you accuse me?

Norman Kranium wrote:
if you insist on copying info/posts to Vas privately, fine. that is your right.

What Zach actually asked ....

Zach Wegner wrote to ChrisW:
An initial questions list has already been provided in the thread "Questions for Vas".

I would actually appreciate it if you forwarded the link to Vas. That was the point of what I said ("by no means are you banned").

This has happened from you more times than I can count, or more exactly an untruthful wild accusation from you to me three times now.

What do expect me or anyone else to think of your general level of veracity? And you have the nerve to accuse someone else of program copying. Unbelievable.

Anything else you'ld like to know?

No, thanks. Why would I ask new questions when you wouldn't answer the old ones?
There is nothing in that thread telling you you should send incomplete data.

What a load of tosh.

I asked what to send, Zach pointed to a post.

If I cut bits from it, you'll accuse me of censoring

If I add bits to it, you'll tell me I wasn't asked to do that.

If I send it as it is, you tell me some other nonsense. Why don't I also send so and so else. As if you were the technical question compiler. Are you? No.

I sent what I was asked to send, no more and no less.

And, if your 'side' is so concerned, why doesn't it send the questions itself? Doh!

What a load of tosh Chris...

What i do see (and have seen consistently) is you suggesting to him what should be done and how.

Why are you insisting on sitting in the middle and acting like a communication conduit?

if you insist on copying info/posts to Vas privately, fine. that is your right.

But Zach is perfectly capable of communicating with Vas on his own, and has already done so at length at the rybka forum.

as you suggest, we'll be more than happy to send the questions ourselves...please allow Zach to present his own case.

[chrisw]

It's funny how Chris continues as Vas' personal communication conduit to this forum. (Good word, btw)

Because Chris was asked specifically by Zach to send the material to Vas. Doh!

Can you read?