[postgis-users] bounding box incorrect on circularstring

[Mark Cave-Ayland]

Ken Southerland wrote:
> I am using Postgres 8.2.4 on Windows and am having an issue with the 
> Circular Strings in the Postgis extension.
> 
> Why is the bounding box of circularstrings incorrectly calculated.  Here 
> I have a circular string that represents a nearly closed circle...
> 
> db=# SELECT astext( geom ) FROM geom_table WHERE id = 0;
> 
> ---------------------------------------
>  CIRCULARSTRING(220268.439465645 150415.359530563,220227.333322076 
> 150505.561285
> 879,220227.353105332 150406.434743975)
> 
> 
> ... but it's extent is a rectangle that only covers the two endpoints 
> and ignores the middle point and the arc segments in-between...
> 
> db=# SELECT astext( extent( geom ) ) FROM geom_table WHERE id = 0;
> 
> ---------------------------------------------------------------
>  POLYGON((220227.34375 150406.421875,220227.34375 
> 150415.375,220268.453125 15041
> 5.375,220268.453125 150406.421875,220227.34375 150406.421875))
> 
> ... is this a known issue that is being addressed?
> 
> Ken

Hi Ken,

Which PostGIS version are you using? Any chance you could file this on 
the PostGIS bugtracker?


Many thanks,

Mark.

-- 
Mark Cave-Ayland
Sirius Corporation - The Open Source Experts
http://www.siriusit.co.uk
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