Thomas Lockhart <lockhart@fourpalms.org> writes:
>> This code seems to have been inserted by Tom Lockhart on 1997-07-29
>> (geo_ops.c rev 1.13). Tom, any info on the copyright status?
> None, beyond the info you already resurrected. I vaguely recall that I
> did take the LJ letter as an invitation to reuse algorithms. I would
> guess that I had possible licensing conflicts in mind so would have
> tried to avoid them, but it would probably be best for someone to
> evaluate that from the current code bases. I may have preserved the
> Franks info for attribution of concepts to a specific person and version.
Thanks for answering, Tom. Charles, since you were the one interested,
maybe you could compare the geo_ops.c code to the Franks code and see
if it looks like Tom borrowed code or just the algorithms?
> My (also vague) recollection is that the original Postgres algorithm was
> just broken.
Yeah, I saw while tracing the CVS history that the code you replaced
defined "overlaps" as "bounding boxes overlap", which is surely not good
enough for polygons ;-)
> I would suggest looking at the code, contacting J. Franks
> if there are questions or a need for license clarification or
> authorization, and finding an alternative algorithm if necessary.
The algorithms are probably public-domain, but we might need a
clean-room implementation :-(
regards, tom lane
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