[postgis-tickets] [PostGIS] #4641: ST_TileEnvelope default geometry precision

[PostGIS]

#4641: ST_TileEnvelope default geometry precision
-------------------------+---------------------------
 Reporter:  Algunenano   |      Owner:  pramsey
     Type:  enhancement  |     Status:  new
 Priority:  medium       |  Milestone:  PostGIS 3.1.0
Component:  postgis      |    Version:  master
 Keywords:               |
-------------------------+---------------------------
 Today I was tinkering with ST_TileEnvelope and projections and notice that
 things weren't exact.

 For example, when transforming 0/0/0 to 4326 I'd expect x to go from -180
 to 180; but it is just a tiny bit less:
 {{{
 SELECT ST_AsText( ST_Transform(ST_TileEnvelope(0, 0, 0), 4326));
 st_astext

 -----------------------------------------------------------------------------------------------------------------------------
 ---------------------------------------------------------------
  POLYGON((-179.999999999998 -85.0511287798064,-179.999999999998
 85.0511287798064,179.999999999998 85.0511287798064,179.999999
 999998 -85.0511287798064,-179.999999999998 -85.0511287798064))
 }}}


 I'm not sure if this is worth fixing, but changing to a more precise input
 does return the expected 180:
 {{{
 SELECT ST_AsText(ST_Transform(ST_TileEnvelope(0, 0, 0,
 ST_SetSRID(ST_MakeBox2D(
     ST_Point(- 6378137.0 * pi(), - 6378137.0 * pi()),
     ST_Point(6378137.0 * pi(), 6378137.0 * pi())),3857)), 4326)
 );
                                                          st_astext
 ---------------------------------------------------------------------------------------------------------------------------
  POLYGON((-180 -85.0511287798066,-180 85.0511287798066,180
 85.0511287798066,180 -85.0511287798066,-180 -85.0511287798066))
 }}}

 Any thoughts?

-- 
Ticket URL: <https://trac.osgeo.org/postgis/ticket/4641>
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