Hi,<div><br></div><div>I am reprojecting a layer of Minnesota county boundaries from epsg:26915 to be commensurate with a google maps overlay (epsg:3857 aka epsg:900913). The county overlay is shifted down from the Google Maps map by I'm guessing to be about 10 miles. Relevant links to map with Openlayers, straight mapserver map of counties, and the contents of the mapfile for the counties are below.</div>
<div><br></div><div>My question is: Do I have a data problem, or is it a mapserver reprojection problem? Or is it a proj4 reprojection problem?</div><div><br></div><div>In addition, I am including the epsg codes and the proj.4 equivalents I got from <a href="http://spatialreference.org">spatialreference.org</a> and stuck into my proj/epsg file:</div>
<div><br></div><div># got proj/epsg entries from proj4 link at: <a href="http://spatialreference.org/ref/sr-org/6864/">http://spatialreference.org/ref/sr-org/6864/</a> :</div><div><div><3785> +proj=merc +lon_0=0 +k=1 +x_0=0 +y_0=0 +a=6378137 +b=6378137 +towgs84=0,0,0,0,0,0,0 +units=m +no_defs <></div>
<div><3857> +proj=merc +lon_0=0 +k=1 +x_0=0 +y_0=0 +a=6378137 +b=6378137 +towgs84=0,0,0,0,0,0,0 +units=m +no_defs <></div><div><900913> +proj=merc +lon_0=0 +k=1 +x_0=0 +y_0=0 +a=6378137 +b=6378137 +towgs84=0,0,0,0,0,0,0 +units=m +no_defs <></div>
</div><div><br></div><div>Help is much appreciated,</div><div><br></div><div>Thanks,</div><div>Matt</div><div><br></div><div>--------------------------------------------------------------------------------------------------------------------------</div>
<div>Map Overlays: <a href="http://209.20.85.148/scratch/google-state.htm">http://209.20.85.148/scratch/google-state.htm</a></div><div><br></div><div>Straight mapserver output of county overlay: <a href="http://209.20.85.148/cgi-bin/mapserv?mode=map&map=/var/www/scratch/county-epsg900913.map">http://209.20.85.148/cgi-bin/mapserv?mode=map&map=/var/www/scratch/county-epsg900913.map</a></div>
<div><br></div><div>County Map (epsg:26916) mapfile (county-epsg900913.map):</div><div>=========================</div><div><div><br></div><div>MAP</div><div> ################</div><div> # Map attributes</div>
<div> ################</div><div> IMAGETYPE PNG</div><div><br></div><div> # epsg:3785 <a href="http://spatialreference.org/ref/epsg/3785/proj4/">http://spatialreference.org/ref/epsg/3785/proj4/</a></div><div>
# Convert</div><div> EXTENT -10779406.34 5378456.81 -9951631.67 6334157.39</div><div> PROJECTION</div><div> "init=epsg:3857"</div><div> END</div><div><br></div><div> SIZE 700 700</div>
<div> IMAGECOLOR 244 244 244</div><div> FONTSET "/home/matt/votevis/mapserver-files/fonts/fonts.list"</div><div><br></div><div><br></div><div><br></div><div> ################</div><div> # Layers</div>
<div> ################</div><div><br></div><div><br></div><div> #---------------------------------------------------------------</div><div> # Counties</div><div> # Renders different thickness borders at different scales</div>
<div> #---------------------------------------------------------------</div><div> LAYER</div><div> NAME "county"</div><div> DATA "/home/matt/votevis/MN/2010-election/shp/shp_counties"</div>
<div> STATUS default</div><div> TYPE polygon</div><div><br></div><div> PROJECTION</div><div> "init=epsg:26915"</div><div> END</div><div><br></div>
<div> CLASS</div><div> NAME "county_lg"</div><div> STYLE</div><div> OUTLINECOLOR 111 111 111</div><div> COLOR -1 -1 -1</div><div> WIDTH 3</div>
<div> END</div><div> END</div><div><br></div><div> END # Layer county</div><div><br></div><div>END # MAP</div><div><br></div><div><br></div>-- <br>Do not seek to follow in the footsteps of the wise men of old. Seek what they sought.<br>
<br>- Matsuo Munefusa (”Basho”)<br>
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