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R3/IPPOLIT/RobboLito/GPL -- but no Fruit!

Posted: Sat Jan 29, 2011 3:16 am
by BB+
Sorry to quote TalkChess yet again (but indeed, it is my fault in first place):
There is a section where BB identifies a silly piece of code in Rybka, where it checks for a capture needlessly which is a performance bug. Ippolit has the same bug in the same piece of code.
This was later discussed the A smoking gun? thread. I was partially conflating IPPOLIT and RobboLito (which differ).
Oops, now that I look at the original IPP_ENG.c, it seems that the condition actually does do something at that juncture, but that the prior condition was added by the time of RobboLito (at some point, I switched to using RL and later renditions as the base of comparison, as they are more readable, and only spot-checked versus the original). Shame on me for not double-checking. :oops:
So in the end, the original IPP_ENG.C did have the same condition as Rybka (though a different action upon it being true), and it looks like it was only in RobboLito that the code became "redundant".
As usual, I agree with most of what DD says (for instance, that IPPOLIT is a "derivative" of R3). In this: "He [BB] set out to prove it was not a clone and I think he ended up proving that it was derivative, and not a clone" -- I think pointed out previously that the original intended audience (many months before the document was completely written) was the Rybka Forum, and one purpose was as DD says: to show that it was not a clone (indeed, no "copied code", except for that one bit that I thought could be, and proceeded to botch up). Whether or not it was a "derivative" was something that I tried to leave mostly up the reader, choosing to (somewhat drily) enumerate facts instead. [If it matters: I think that IPPOLIT is a R3 derivative, certainly from the "computer chess" standpoint, and possibly from the copyright side (whether or not the RE was "clean room" could matter here)]. I also agree that I might not necessarily be as "objective" as I strive, and have always said that it should be useful for VR to state whatever evidence he possesses.
My very first impression when seeing the Ippolitto source was that is written by a complete amateur. It was just awful crap from a programming style point of view, and hardly any comments whatsoever.
My first impression was that they had run something (either one file, or many and then concatenated) through a C preprocessor. :lol: Upon assuming that, I'm not quite sure what could be said style-wise.

On the GPL point, it seems to me that every version from the "IPPOLIT wiki" has been "PUBLICDOMAIN (workers)", and it is only kranium's RobboLito that is GPL, but I could be mistaken.
You cannot take public domain code and make it GPL just by adding a license file!
I think you can. If you do so, and someone uses your GPL version rather than the public domain version, the Gnu GPL applies. [This is actually occurring with some old song lyrics (old enough to be public domain) -- change a few pronouns to make it "politically correct" and gain copyright to boot!].

Jeremy: is there a way I can replace the old PDF for the R3/IPPOLIT document with a new version? Actually, ZW posted that, so it's likely twice impossible.

Re: R3/IPPOLIT/RobboLito/GPL -- but no Fruit!

Posted: Sat Jan 29, 2011 6:20 am
by kingliveson
BB+ wrote:[...]
On the GPL point, it seems to me that every version from the "IPPOLIT wiki" has been "PUBLICDOMAIN (workers)", and it is only kranium's RobboLito that is GPL, but I could be mistaken.
You cannot take public domain code and make it GPL just by adding a license file!
I think you can. If you do so, and someone uses your GPL version rather than the public domain version, the Gnu GPL applies. [This is actually occurring with some old song lyrics (old enough to be public domain) -- change a few pronouns to make it "politically correct" and gain copyright to boot!].

[...]
I suspect Milos is correct that you cant take public domain source code and then slap GPL on it.

http://www.gnu.org/licenses/gpl-faq.html
If a program combines public-domain code with GPL-covered code, can I take the public-domain part and use it as public domain code?

You can do that, if you can figure out which part is the public domain part and separate it from the rest. If code was put in the public domain by its developer, it is in the public domain no matter where it has been.