Ben,
See Regina Obe's upgis_lineshift
http://trac.osgeo.org/postgis/wiki/UsersWikiplpgsqlfunctions
I have a PostGIS version, without the curves, of this one:
http://www.spatialdbadvisor.com/oracle_spatial_tips_tricks/97/implementing-a-move-parallel-function-for-sdo_geometry-linestring-data-in-oracle
If you want the code, email me privately as I have not yet blogged on it.
Simon
On Thu, 23 Dec 2010 14:56:49 +1100, Ben Madin <li...@remoteinformation.com.au> 
wrote:

Thanks Brent,

Happy Christmas / New Year to you as well!

On 23/12/2010, at 2:07 PM, pcr...@pcreso.com wrote:

ST_Translate() is the simplest, but if your lines are horizontal you may want a 
Y shift as well?

http://postgis.refractions.net/documentation/manual-svn/ST_Translate.html

Lines are roads, so they go every which way.

Having done this, I suggest you also use ST_reverse() to reflect the direction 
is now going the other way (unless it already is :-)
http://postgis.refractions.net/documentation/manual-svn/ST_Reverse.html

For more complex shifting of features, probably overkill in your case, see
http://postgis.refractions.net/documentation/manual-svn/ST_Affine.html

This might be what I am after, but I was thinking of somehow translating each 
segment parallel to it's current alignment and then rejoining with a nice 
smooth curve... kind of like a 1-sided buffer.

cheers

Ben





--- On Thu, 12/23/10, Ben Madin <li...@remoteinformation.com.au> wrote:

From: Ben Madin <li...@remoteinformation.com.au>
Subject: [postgis-users] Shifting linestrings left
To: "PostGIS Users Discussion" <postgis-users@postgis.refractions.net>
Date: Thursday, December 23, 2010, 3:13 PM

G'day all,

I have a problem where I am trying to show the route of livestock movements, 
but I am loosing information when the travel along the same road in different 
directions (ie in some cases they travel from a saleyard to a feedlot, then 
back to the saleyard after a period). The roads they travel along are single 
linestrings.

Is there a way to 'shift' the linestring to the left - after all, that would be 
sensible side of the road to drive on...

cheers

Ben


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