[postgis-devel] [PostGIS] #749: Bounding Box calculation disagrees with cached bounding box ST_GeomFromText/ST_GeomFromEWKT weirdness

[PostGIS]

#749: Bounding Box calculation disagrees with cached bounding box
ST_GeomFromText/ST_GeomFromEWKT weirdness
---------------------+------------------------------------------------------
 Reporter:  robe     |       Owner:  pramsey      
     Type:  defect   |      Status:  new          
 Priority:  medium   |   Milestone:  PostGIS 2.0.0
Component:  postgis  |     Version:  trunk        
 Keywords:           |  
---------------------+------------------------------------------------------
 I don't know if this is limited to empty geometries or not, but there
 seems to be something whether bizarre going on with cached vs. non-cached
 boxes. Botht he gserialized and non-gserialized (current) display some
 suspicious behavior though the behavior is different:

 {{{
 SELECT foo1.wktgeom && foo1.wktgeom As wktint, foo1.ewktgeom &&
 foo1.ewktgeom As ektint, PostGIS_DropBBOX(foo1.ewktgeom) &&
 PostGIS_DropBBOX(foo1.ewktgeom) As ektdint,
     Box2d(foo1.wktgeom) as wktbox,Box2d(foo1.ewktgeom) as ewktbox,
      foo1.wktgeom::bytea = foo1.ewktgeom::bytea As binaryequal

     FROM (

         (SELECT ST_GeomFromText('GEOMETRYCOLLECTION EMPTY') As wktgeom,
             ST_GeomFromEWKT('GEOMETRYCOLLECTION EMPTY') As ewktgeom  )

     ) As foo1 ;
 }}}

 -- with gserialized enabled
 the output of the above is: (note the boxes are NULL which I guess is
 fine)
 wktint | ektint | ektdint | wktbox | ewktbox | binaryequal
 -------+--------+---------+--------+---------+-------------
 f      | t      | f       |        |         | t


 NOTE: The difference between ektint (this is with the cached bounding
 box), and ektdint -- when I drop the cached bounding box I get a different
 answer (which agrees with the ST_GeomFromText answer).

 -- with gserialized off (our current svn) --
  wktint | ektint | ektdint |    wktbox    |   ewktbox    | binaryequal
 --------+--------+---------+--------------+--------------+-------------
  t      | t      | f       | BOX(0 0,0 0) | BOX(0 0,0 0) | t

 I assume I should not be concerned that the bounding boxes of serialzed
 vs. gserialized are at odds?

-- 
Ticket URL: <http://trac.osgeo.org/postgis/ticket/749>
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