[postgis-tickets] [PostGIS] #4618: ST_Buffer(geography) issue

[PostGIS]

#4618: ST_Buffer(geography) issue
-----------------------+---------------------------
 Reporter:  olehz      |      Owner:  pramsey
     Type:  defect     |     Status:  new
 Priority:  medium     |  Milestone:  PostGIS 3.0.1
Component:  postgis    |    Version:  3.0.x
 Keywords:  ST_Buffer  |
-----------------------+---------------------------
 It seems that ST_Buffer(geography point, float radius_of_buffer) works
 incorrect. If you visualize the blue and red circles, you will see that
 they do not match. Blue is slightly smaller than red. The difference is
 about 90 km from the west and east side.

 Is this a bug or am I not understanding something?

 {{{
 SELECT 'blue' AS color, ST_Buffer(c, dist, 90) AS geom FROM params
 UNION
 SELECT
     'red' AS color, ST_MakePolygon(ST_MakeLine(points || points[1])) AS
 geom
 FROM (
     SELECT
         ARRAY_AGG(p) points
     FROM params,
         generate_series(0, 359, 1) deg,
         Geometry(ST_Project(c, dist, RADIANS(deg))) p
 ) z
 }}}

 [[Image(https://nadoloni.com/buffer.png)]]

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Ticket URL: <https://trac.osgeo.org/postgis/ticket/4618>
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