[postgis-tickets] [PostGIS] #3355: ST_Intersects() return no result with ST_Segmentize()

[PostGIS]

#3355: ST_Intersects() return no result with ST_Segmentize()
----------------------+---------------------------
  Reporter:  sdiz     |      Owner:  pramsey
      Type:  defect   |     Status:  new
  Priority:  blocker  |  Milestone:  PostGIS 2.1.9
 Component:  postgis  |    Version:  2.1.x
Resolution:           |   Keywords:
----------------------+---------------------------
Changes (by robe):

 * priority:  high => blocker


Comment:

 Seems to be something amiss with the boxes.  When it comes out of
 ST_Segmentize, it gets a regular old bounding box instead of a gbox.

 I'm tested this on both 2.1.8 and 2.2.0


 {{{
 SELECT  ST_Summary(geog_before) As before,  ST_Summary(geog_after) As
 after, ST_Intersects(geog_before,geog_after)
        FROM (SELECT
          'LINESTRING(124.983539 1.419224,91.181596 29.647798)'::geography
 As geog_before
        , ST_Segmentize('LINESTRING(124.983539 1.419224,91.181596
 29.647798)'::geography, 47487290) As geog_after) AS f;
 }}}

 outputs:


 {{{
             before            |            after            |
 st_intersects
 ------------------------------+-----------------------------+---------------
  LineString[GS] with 2 points | LineString[S] with 2 points | f
 }}}

 Trying to recast to geography doesn't help because it's already a
 geography (so guess it doesn't think updating the box is needed, however
 double casting works:


 {{{

 SELECT  ST_Summary(geog_before) As before,
 ST_Summary(geog_after::geometry::geography) As after,
     ST_Intersects(geog_before,geog_after::geometry::geography)
        FROM (SELECT
          'LINESTRING(124.983539 1.419224,91.181596 29.647798)'::geography
 As geog_before
        , ST_Segmentize('LINESTRING(124.983539 1.419224,91.181596
 29.647798)'::geography, 47487290) As geog_after) AS f;

 }}}

 outputs:


 {{{
             before            |             after             |
 st_intersects
 ------------------------------+-------------------------------+---------------
  LineString[GS] with 2 points | LineString[BGS] with 2 points | t
 }}}

--
Ticket URL: <https://trac.osgeo.org/postgis/ticket/3355#comment:3>
PostGIS <http://trac.osgeo.org/postgis/>
The PostGIS Trac is used for bug, enhancement & task tracking, a user and developer wiki, and a view into the subversion code repository of PostGIS project.