

http://64.68.157.89/forum/viewtopic.php?start=0&t=23118&topic_view=flat
The interesting thing that I found is that for this piece of code, Rybka 1.0 is more similar to Fruit than Strelka. Here are the differences:
> --I noted earlier that the history initialization was different. Strelka and Rybka 1.0 are the same here, using memset(History, 256, 12 * 64 * sizeof(int)); But what I didn't notice is, 256 is out of range for an unsigned char. So that code is the same as Fruit's memset(History, 0, 12 * 64 * sizeof(int)); Why would Rybka 1.0 have 256? Is it the optimizer gone wild, or a deliberate attempt at obfuscation?
Maybe somebody can summarize the points.
Generally, code theft is easy to show - just show the two sections of identical code, side-by-side. There isn't much to debate in such cases. Rybka is of course original (with some accepted exceptions like bit scans & bit counters, etc). Strelka contains Rybka code. Whether Strelka also contains Fruit code, I don't know and don't really care.
Re. algorithms and structures - sure, you'll get a lot of similarity between programs. Take something like "modern move ordering" - by this, I mean hash move, non-losing captures (by MVV/LVA), killers, non-captures, and losing captures. The chance of two programmers settling on this independently is more or less zero.
Vas
> This discussion looks like a complete mess, I see wild statements like:
>
>> --I noted earlier that the history initialization was different. Strelka and Rybka 1.0 are the same here, using memset(History, 256, 12 * 64 * sizeof(int)); But what I didn't notice is, 256 is out of range for an unsigned char. So that code is the same as Fruit's memset(History, 0, 12 * 64 * sizeof(int)); Why would Rybka 1.0 have 256? Is it the optimizer gone wild, or a deliberate attempt at obfuscation?
OK, fair enough, that was wrong. I was thrown off by Strelka's memset--which is an incorrect translation of the Rybka code. More correct is for (x = 0; x < 864; x++) History[x] = 256; Memset works with bytes, but the Rybka code (rep stosd) works on ints (double words).
What the hell is wrong with that?
> enerally, code theft is easy to show - just show the two sections of identical code, side-by-side. There isn't much to debate in such cases. Rybka is of course original (with some accepted exceptions like bit scans & bit counters, etc). Strelka contains Rybka code. Whether Strelka also contains Fruit code, I don't know and don't really care.
Agreed. Strelka is a Frankenstein. Some of Rybka, maybe some of Fruit and who knows what else.
>> enerally, code theft is easy to show - just show the two sections of identical code, side-by-side. There isn't much to debate in such cases. Rybka is of course original (with some accepted exceptions like bit scans & bit counters, etc). Strelka contains Rybka code. Whether Strelka also contains Fruit code, I don't know and don't really care.
> Agreed. Strelka is a Frankenstein. Some of Rybka, maybe some of Fruit and who knows what else.
At least three people have confirmed that Strelka and Rybka are virtually identical.
Note the tense change. He claimed it with that sentence. He just never rereleased it.
I think Vas needs to clarify it, he cannot claim it as his own if it contains Fruit code.
IMO Strelka should be completely omitted from these comparisons, if it's about what Rybka contains or not.
> And one of them was Vasik Rajlich. He claimed Strelka to be his own. Now is it or is it not?
I made quite a detailed post about this around the time of the Strelka 2.0 release, maybe someone can dig it up.
Claiming Strelka as my own would have been illegal, so I didn't do it.
Vas
http://64.68.157.89/forum/viewtopic.php?t=20730&postdays=0&postorder=asc&highlight=strelka&topic_view=flat&start=30
Rick Fadden
By the way, some people are using the word "clone", and from past experience clone is used for a more mellow activity than this.
About the word "clone" in the context of a chess program:
Long ago some people took the open source code of Crafty and they changed some of the strings output by the program and they compiled and used the resulting binary, and these programs were identified as clones.
Fruit 2.1 open source was used with new developments or improvements and the result is considered a clone of Fruit.
Take a version of Fritz that plays 2850 uniprocessor 32 bit and disassemble it and completely recreate the C of the Original Fritz, and call this program "Jury" and then claim that you have made one of the best programs on the planet.
I wouldn't describe that as a clone of Fritz, that's a stolen, reverse engineered Fritz, and the result is a Fraud.
Stelka is not a clone, it's a Fraud. It is a direct Reverse Engineer of Rybka, and I can show you the exact constants, the exact math taken from Rybka, every function call in exactly the same location being passed exactly the same arguments, the same values and the same constants. A *direct* reverse engineering effort. There is no original content in Strelka, it is all a direct rip-off with some chunks of stuff left out.
I found one specially commented line of code that was not in Rybka, and then we found that line of code came from Fruit.
What a pure and complete rip off.
----
When I put on my temporary "reverse engineer" hat I also say that it was an amazing feat of reverse engineering. To do this effort would have taken me a year of effort. I think the person Jury or whoever, has some excellent skill.
I probably shouldn't say this but honestly I am now reading Rybka like a complete "open book." There is one reason why I can see everything. Because I used Strelka as the "primer" (similar to the use of the term in the movie "Contact"). With the "primer" in hand I was able to label every single variable in Rybka, and the position of these variables lines up in the same order as the variables in Strelka. It's spooky. All functions are called in exactly the same order, from the same functions.
There is no coincidence here because all of the wired constants in the x86 code are in Strelka in exactly the same spot. I'm saying the "primer" showed me everything, it completely exposed all of Rybka.
I was able to find all details of Node Count, and I was then able to patch Rybka to remove the node count obfuscation. Before I had the "primer" in my hand I could not have done this, I could not have labeled all of the varibales in Rybka. Strelka 2.0 is the primer it is the "open book" of Rybka.
V.Rajlich: Whether Strelka also contains Fruit code, I don't know and don't really care.
How can you say you don't care about Fruit parts in Strelka when you claimed Strelka as your engine?
Vas
> Really, only Yuri Osipov knows how Strelka was made.
>
Many people know, and I would think you would too.
Vas






children and feudal censorship. only
confirms the theory of double moral. thx anyway

i'm surprised felix didn't know about this.... i didn't, but i'm not involved in these kinds of things...
either you're the biggest pain in the


I believe Felix deleted the thread by mistake, it's something that keeps happening due to software flaws (i.e. it doesn't know about the recycle bin concept of restoring threads for such cases).
Second page of the old thread.
You can continue just like nothing has happened ;)
If anything, a link to the old thread would have sufficed.
> There are several precedents of themes that resurface over time on Rybka Forum (like God's ELO, or Religious Wars) and if the old thread is old enough (here we're talking >2 years) there's no need for a merge.
I think (some of) those should be moved to a new subforum called <opposite of edge> that only people with less than 500 posts can see.
> a new subforum called <opposite of edge>
Sorry, I think we've already exhausted those resources.
But for such a forum I'd suggest the name: The Inside.

I'm glad how he handles all this mess with an open mind. Haaa!! I saw another post that says Banned For Life interviewed Vasik. Shocking how people could twist the facts!!

They'd have to keep clicking the [+] of each branch to read it, or mark all forums old and read and then enter the thread again to see all branched expanded. So, just a link would have been better, even without the accident.


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