OpenChess

Jeremy Bernstein wrote: Considering the amount of work that Houdart is putting into Houdini, it would honestly surprise me if he didn't start charging for it. Since the IPPOLIT code is public domain, and since there's still no consensus on where that code comes from, there's nothing objectively illegal about it, either, but I maintain that it's pretty lame. OTOH, he's brought the IPPOLIT code base much further than anyone else, both strength and feature-wise. Ah, ethics...
Jeremy

?
Many agree (and there's a fair bit of evidence) that Houdini is most likely based on RobboLito 0.085g3 or RobboLito 0.09...
both of which were released (by myself and Sentinel) under GPL license.

Some may argue we didn't have the right to attach GLP license to what was originally released as public domain software,
but I disagree...

We had made many changes, code translations, features added, bugs fixed, speed and strength improvements...
the addition of the GPL was an (apparently unsuccessful?) attempt to protect our work on the code, and to deter others from using it in a commercial endeavor.

Norm

kranium wrote:

Jeremy Bernstein wrote: Considering the amount of work that Houdart is putting into Houdini, it would honestly surprise me if he didn't start charging for it. Since the IPPOLIT code is public domain, and since there's still no consensus on where that code comes from, there's nothing objectively illegal about it, either, but I maintain that it's pretty lame. OTOH, he's brought the IPPOLIT code base much further than anyone else, both strength and feature-wise. Ah, ethics...
Jeremy

?
Many agree (and there's a fair bit of evidence) that Houdini is most likely based on RobboLito 0.085g3 or RobboLito 0.09...
both of which were released (by myself and Sentinel) under GPL license.

Some may argue we didn't have the right to attach GLP license to what was originally released as public domain software,
but I disagree...

We had made many changes, code translations, features added, bugs fixed, speed and strength improvements...
the addition of the GPL was an (apparently unsuccessful?) attempt to protect our work on the code, and to deter others from using it in a commercial endeavor.

Norm

It's more or less an identical situation to the Vas/Fruit scenario, just that the original code was (probably) unlicensed, or unclearly so. I don't know the legality of attaching the GPL license to a modified version of "someone else's" code, even if that code is public domain. There are probably reasonable arguments for and against (including your argument of protection of additions and modifications -- OTOH maybe you'd be required to GPL the diffs only?) Unclear. In any case, I would certainly modify your "most likely" to "beyond any reasonable doubt". Houdini 1.0 was Robbolito+ (although which source release of Robbolito it's based on is pretty relevant).

If Robert starts to sell Houdini, you could certainly contact the FSF -- the history of IPPOLIT might complicate matters, though, in addition to the above. My sense is that he's going to just get away with it.

Jeremy

kranium wrote:

Jeremy Bernstein wrote: Considering the amount of work that Houdart is putting into Houdini, it would honestly surprise me if he didn't start charging for it. Since the IPPOLIT code is public domain, and since there's still no consensus on where that code comes from, there's nothing objectively illegal about it, either, but I maintain that it's pretty lame. OTOH, he's brought the IPPOLIT code base much further than anyone else, both strength and feature-wise. Ah, ethics...
Jeremy

?
Many agree (and there's a fair bit of evidence) that Houdini is most likely based on RobboLito 0.085g3 or RobboLito 0.09...
both of which were released (by myself and Sentinel) under GPL license.

Some may argue we didn't have the right to attach GLP license to what was originally released as public domain software,
but I disagree...

We had made many changes, code translations, features added, bugs fixed, speed and strength improvements...
the addition of the GPL was an (apparently unsuccessful?) attempt to protect our work on the code, and to deter others from using it in a commercial endeavor.

Norm

GPL does not restrict commercialization. But if you meant that because they would have to publish the source along and that would not be enticing, then yes...

Hey guys, what are you talking about? Any real reason to believe that Houdini is based on Robbolito 0085 (GPL) but not on Robbolito 0084 (public domain)? And not on some version of Ivanhoe? LOL.

Norman, I may be mistaken but I recall you published your first Italian to English translation of Robbo (btw, thank you very much) without GPL.

ThinkingALot wrote:Hey guys, what are you talking about? Any real reason to believe that Houdini is based on Robbolito 0085 (GPL) but not on Robbolito 0084 (public domain)? And not on some version of Ivanhoe? LOL.

Norman, I may be mistaken but I recall you published your first Italian to English translation of Robbo (btw, thank you very much) without GPL.

in RobboLito-0.084 simple integers are used to report vars in UCI info strings via printf:
info time %d nodes %d nps %d cpuload %d

in RobboLito_0085g3 I defined/declared an fairly unique unsigned 64-bit integer type: I64u
info time %I64u nodes %I64u nps %I64u cpuload %u

this unsigned integer type is also found in the Houdini w32 1_CPU binary:
info time %I64u nodes %I64u nps %I64u cpuload %u

there's more...
but i don't consider it definitive...see my precise wording above (i.e. most-likely).
it's clearly based on robbolito...this can easily be proven, but exactly which version?
much more difficult...

anyway...
my understanding is that by releasing Robbolito 0.085g3 and 0.09 with GPL, it becomes wholly retroactive to any and all of my previous releases!

Just want to add:

Robert Houdart, you listen to suggestions, bug reports, and make fixes accordingly. It's why you're a better programmer and your engine's strong and stable for analysis.
Rock on, Robert Houdart