[postgis-tickets] [PostGIS] #5095: Unexpected ST_DWithin result when using geography

[PostGIS]

#5095: Unexpected ST_DWithin result when using geography
---------------------+---------------------------
 Reporter:  satoshi  |      Owner:  pramsey
     Type:  defect   |     Status:  new
 Priority:  medium   |  Milestone:  PostGIS 3.3.0
Component:  postgis  |    Version:  3.2.x
 Keywords:           |
---------------------+---------------------------
 Hello,

 This query:

 {{{
 SELECT ST_DWithin(
   ST_Buffer('SRID=4326;LINESTRING(7.1670005 45.9968257,7.1670216
 45.9969537,7.1670216 45.9971326, 7.1670484 45.9972789, 7.1671905
 45.9974074, 7.1672844 45.9974801, 7.1659165 46.0005209, 7.1653103
 46.0010221, 7.1652359 46.0013015)'::geography, 1.0),
   'SRID=4326;POINT(7.1672844 45.9974801)'::geography,
   0.0
 );
 }}}

 Returns `FALSE`. Note that the point that is passed as the second
 parameter to `ST_DWithin` is part of the `LINESTRING` passed in the first
 parameter, so I expect it to return `TRUE`.

 When removing the first or last point from the `LINESTRING`, then it
 correctly returns `TRUE`.

 When using `geometry` instead of `geography` and using 0.0000105 for the
 buffer (which is roughly 1 meter at that latitude), then it correctly
 returns `TRUE`.

 I think this is a bug?

 Thank you,

 Dario

-- 
Ticket URL: <https://trac.osgeo.org/postgis/ticket/5095>
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