Re: BUG #5889: "Intersects" for polygons broken

On Wed, Feb 16, 2011 at 10:33 AM, Konrad Garus <konrad(dot)garus(at)gmail(dot)com> wrote:
> 2011/2/16 Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>:
>> "Konrad Garus" <konrad(dot)garus(at)gmail(dot)com> writes:
>>> && operator seems to be broken for polygons whose bounding boxes intersect:
>>
>>> select polygon'((0,0), (1,2), (0,2))' && polygon'((0.5, 0), (1,0), (1,1))';
>>>  ?column?
>>> ----------
>>>  t
>>> (1 row)
>>
>> This is fixed as of 9.0; see the release notes at
>> http://www.postgresql.org/docs/9.0/static/release-9-0.html
>> which say
>>
>>        Correct calculations of "overlaps" and "contains" operations for polygons (Teodor Sigaev)
>>
>>        The polygon && (overlaps) operator formerly just checked to see
>>        if the two polygons' bounding boxes overlapped. It now does a
>>        more correct check. The polygon @> and <@ (contains/contained
>>        by) operators formerly checked to see if one polygon's vertexes
>>        were all contained in the other; this can wrongly report "true"
>>        for some non-convex polygons. Now they check that all line
>>        segments of one polygon are contained in the other.
>
> Thank you. How about the point of more informative docs that would
> explain supported types, automatic conversions and all such caveats
> (also for 8.3 and 8.4)?

I think a lot of these things are already documented. Aren't they?

--
Robert Haas
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