[postgis-tickets] [PostGIS] #4274: ST_PointOnSurface generated point produces ST_Intersects = false

[PostGIS]

#4274: ST_PointOnSurface generated point produces ST_Intersects = false
---------------------+---------------------------
 Reporter:  andehhh  |      Owner:  pramsey
     Type:  defect   |     Status:  new
 Priority:  medium   |  Milestone:  PostGIS 2.5.2
Component:  postgis  |    Version:  2.4.x
 Keywords:           |
---------------------+---------------------------
 Given is this query which returns 'false':

 {{{
 SELECT ST_Intersects(ST_PointOnSurface(poly), poly) FROM (SELECT
 'SRID=4326; POLYGON ((2.0875049999999997 49.038467, 2.087497642793396
 49.0384427212182, 2.087475 49.038368, 2.0875049999999997
 49.038467))'::geometry AS poly) AS foo;
 }}}


 Looking at the documentation ("Returns a POINT **guaranteed** to intersect
 a surface.") this case should be handled internally to avoid confusion.

 Can it be explained with rounding issues as the polygon in question is a
 very narrow sliver polygon?

 When transforming to a metric system this issue disappears.

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Ticket URL: <https://trac.osgeo.org/postgis/ticket/4274>
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