Official GPL webpage available?

[Frank Quisinsky]

Hi Norman,

after my information PD to GPL is possible.
GPL to PD isn't possible.

Can't see in any things you do with Robbolito / IvanHoe and Fire a problem. What you wrote about it is absolutely correct too.

Fruit - Rybka ... I think the most important parts are from Vas (newer Rybka versions). Older Rybka versions can be really based on Fruit if I understand the messages about it. I think what Robert wrote here and others find out is also clear.

But all in all:
Question here is: What is a clone?

Rybka - IPP ... on this position I missed the proof since two years.

Best
Frank

[rbarreira]

Sorry ... but you cannot GPL code that is not yours. You cannot use public domain code and change it a bit and then claim it is your original creation and GPL it.

Yes you can... public domain means public domain.

You cannot do the opposite: take GPL code and make it public domain.

I guess you can plaster a GPL license on anything, but I could also claim that I am King of the United States of America. It might make me happy, but chances are that nobody will take me seriously ... and I would have a hard time enforcing my kingdom. I would love to see how someone would go around trying to enforce a GPL license from something he copied from PD.

It is pointless if no modifications are made (i.e. the GPL version is exactly equal to the PD version). But if significant modifications are made, you may prove that someone copied the GPL version and not the PD one.

[Thomas Mayer]

Sorry ... but you cannot GPL code that is not yours. You cannot use public domain code and change it a bit and then claim it is your original creation and GPL it.

Yes you can... public domain means public domain.

You cannot do the opposite: take GPL code and make it public domain.

I guess you can plaster a GPL license on anything, but I could also claim that I am King of the United States of America. It might make me happy, but chances are that nobody will take me seriously ... and I would have a hard time enforcing my kingdom. I would love to see how someone would go around trying to enforce a GPL license from something he copied from PD.

Well, of course you can GPL it even if it is not yours. Of course the parts that were public domain still stay public domain. The original Ippo was a very strange source, so the work done for Robbolito was immense. The problem might be: if it stays semantically equivalent it might be anyway still public domain even when some put the GPL-stamp on it. But I am not a lawyer and in fact that does not interest me much -> anyway, if a program - let's call it Houdini - is based on a public domain source it is completely legal, no doubt about that - but it won't be allowed to any real programmers contest. Because at least some parts are not the original work of the author.

Greets, Thomas

[Thomas Mayer]

you must be confused, that's completely wrong.

Not completly, but wrong, yes.

RobboLito 0.09 is still available for download from chesslogik.com.
It is GPL'd and always has been.

Yes, it is available now. Last time I checked it wasnt there - I think ... but, so what.

RobboLito 0.09 was released on 12/31/2009...well before the 1st Houdini release -> 5/16/2010
and RobboLito 0.09 was the very last release of my and Sentinel's Chesslogik RobboLito development series,
so all previous versions have an even earlier release date.

Whatever you say, but the copyright notice wasn't always there AND the original code still is PD until today! Which means, except the "missing downlaod for 0.9" nothing factual changes on what I have written.

Ingo

Besides, Ingo, don't forget: if something is not explicitely marked as Public Domain it is of course not free. As far as I know initial Ippo & Ivanhoe & Igorrit were marked as public domain, but of course I might be wrong.
Because I didn't follow all the sources of the Ipp* family - maybe Norman can enlight us here: Is Ivanhoe a direct follow up of Ippolit or Igorrit or is it at least partly based on Robolito. (Whatever license consequence this might have) Anyway, for the moment I think that Houdini is legal, at least as long no-one proves either his code base was GPLed or Ippolit itself is illegal.

Greets, Thomas

[Frank Quisinsky]

Robert,

again ...

I think that Houdini is a copy of one of the older IvanHoe versions should be clear after all what we can read about it. The information by Lance Perkens are also quiet clear for me. If I look in older IvanHoe versions and compare it with the first Houdini's I see the same engine.

Fruit older Rybka versions:
Here you and others gave many proofs that first Rybka versions are based on Fruit.

But I missed a clear defination about "Clone".
Unclear is which parts of a chess program can give me the information "Clone" or not, if we find out that they parts must be a 1:1 copy.

Later the Rybka versions are stronger and stronger, around 250-275 ELO stronger as Fruit. The main parts of Rybka can't be a clone from Fruit or other engines.

Later this main parts from Rybka which are clearly stronger as Fruit are recompiled. I missed a clear proof about it. The sources are available as PD. Norman gave his sources as GPL. No problem at all.

I can't see any problem in the engines by Norman so long isn't clear that Igorit based on Rybka or is a clone of Rybka or is recompiled. If so this information comes to late, no one gave the proof about it.

I can understand the problem you have with Rybka. But the topic should be over after the ICGA decision.

A problem with Robbolito, IvanHoe and Fire I can't see.

Houdini is quit clear for me.

All in all:
A programmer used Fruit sources (Vas) for his engine Rybka.
Can't be right, Fruit is GPL.

Later Rybka is very strong and over years clearly the number 1. No other programmer have in this time a better engine as Vas.

What is to do?
Basic Rybka is perhaps a clone of Fruit.
Basic sources in later Rybka version can't be a clone of Fruit.

Most important is the basic and the situation that Vas used GPL sources. ICGA decision is right.

But nobody seems to be have interest on the question:
Vas develops a very strong engine, 250-275 ELO stronger as Fruit.

Main question is:
Which status have this strong sources (not open) Vas created for the latest Rybka versions.

Recompiled by others (if this is right).
PD after recompling ...
GPL by Norman.

What is wrong?
If the first Rybka versions based on Fruit, Vas have to give all what he do in the future under GPL too.

Recompile Rybka must have GPL status, right?
But no clearly proofs that it is recompiled, right?

Where is the problem with Igorit, later the engines Norman created?
I can't see any problem!

Problems I can see:
Rybka first versions based on GPL Fruit
Houdini first versions based on GPL Robbolito / Ivanhoe

Both, Rybka and Houdini must be under GPL.
A commercial engine isn't possible, sources must be free available, right?

Best
Frank

[Peter Skinner]

Well, of course you can GPL it even if it is not yours. Of course the parts that were public domain still stay public domain. The original Ippo was a very strange source, so the work done for Robbolito was immense. The problem might be: if it stays semantically equivalent it might be anyway still public domain even when some put the GPL-stamp on it. But I am not a lawyer and in fact that does not interest me much -> anyway, if a program - let's call it Houdini - is based on a public domain source it is completely legal, no doubt about that - but it won't be allowed to any real programmers contest. Because at least some parts are not the original work of the author.

Greets, Thomas

http://www.talkchess.com/forum/viewtopi ... 85&t=40673

I don't know about that one.

As you can see Robert Houdart does now state that Houdini doesn't contain _any_ licensed code other than the Nalimov code.

So that means no RoboLitto code in Houdini, as RoboLitto has a Public Domain license. A license is a license....

He finally answered the question... and appears that Houdini is _all_ original code.

Peter

[Alexander Schmidt]

Besides, Ingo, don't forget: if something is not explicitely marked as Public Domain it is of course not free.

Thanks. I try to explain this here since ages but nobody can hear me

Alex

[Frank Quisinsky]

Thomas,

fact is:
Houdini first versions based on GPL Ivanhoe.
I think what Lance wrote about it is enough.

fact is:
Rybka first versions based on GPL Fruit.
I think too that all is right what Bob and others wrote to this topic.

Houdini can't be legal.
Rybka can't be legal.

If Rybka is recompiled by Igorit people is this not illegal, because Rybka isn't legal. Recompiled Rybka is PD, later by Norman GPL.

Situation with Houdini is easy to solve:
The programmer have to give his sources to ChessOK. Victor have many knowledge about programming and can very easy check that. If Robert working in a team with ChessOK he can do that.

Where is the problem?

If Victor give us the information ... yes Houdini and IvanHoe are totaly different, what the Thinker programmer wrote can't be right ... Houdini is a legal program. Perhaps a second persons should checked that.

And please all this before many people buy Houdini.

Best
Frank

[Frank Quisinsky]

Norman used GPL.
FACT

PD to GPL is possible
FACT

If Houdini based on Ivanhoe (I believe more a 1:1 clone) sources must be available under GPL
FACT

Houdini can't be legal if the information are right.
FACT

Houdini is now available by ChessOK
FACT

The programmers of ChessOK must checked the sources of Houdini after all available information, example information by Lance Perkins
FACT

The programmres of ChessOK and ChessBase must checked the sources of Rybka after all available information.
FACT

[kranium]

The programmers of ChessOK must checked the sources of Houdini after all available information, example information by Lance Perkins
FACT

The programmres of ChessOK and ChessBase must checked the sources of Rybka after all available information.
FACT

Frank:
For clarity...is this what you mean?

The programmers of ChessOK should check the sources of Houdini
YES

The programmers of ChessOK and ChessBase should have checked the sources of Rybka after all available information.
YES


If so....
+100

Thanks for risking the all-to-frequent Good-Old Boys Talkchess ridicule/misinformation/nonsense attacks...
and having the courage to stand up here and speak you mind!