[postgis-users] Fwd: cannot show circle in map use st_buffer

[Nicolas Ribot]

> Hi,
> I used ST_BUFFER(geometry, radius) to get a polygon.
> I viewed the polygon on Geo server, it is a circle, But when I combine Geo
> server and google map, the polygon becomes an eclipse.
>
> I want the polygon calculate from ST_BUFFER(geometry, radius) is a circle
> when view it on map. Please help me.
>
> Thanks and cheers
> Vy Nguyen
>

Hi
Depending on the choosen projection, a circle in cartesian coordinates
appears as an ellipse once projected onto the earth surface due to
surface curvature. It is a normal behaviour.
Here is an interesting page on that: http://www.perrygeo.net/wordpress/?p=4

Nicolas