[postgis-users] Open buffers or parallel lines

[strk]

On Tue, Jun 16, 2009 at 01:52:33PM +0200, Andreas Neumann wrote:
> Hi all,
> 
> I am looking for either a "parallel line" feature or "open buffers around
> a linestring element".
> 
> The idea is to visualize a waste-water system where in large map scales
> the actual diameter of the waste-water pipes (canalization). The linecaps
> shouldn't be stroked, but the parallel offset to the centerline should be
> drawn.
> 
> Are there any tricks how this can be done in Postgis? I see that there is
> st_buffer, but there is no option to get an open buffer or parallel lines.

See if what's currently referred to "Single-Sided-Buffer" and probably
to become "Offset Curve" is what you're looking for.

http://trac.osgeo.org/geos/ticket/215

--strk;

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