Projection trouble

[Ken Lord]

Hi Arnulf,

This is a bit of a guess here, I am no wms expert, but It looks like
your wms server does not have the ability to reproject, and instead of
failing, it is sending the data in its native projection.

I have had the odd projection problem now and then with mapserver
newer than 4.0 as well,  I have found that sometimes it has problems
finding the 'proj' folder.

In 2 different windows setups I have found that I have had to place
the proj folder at 'c:\proj' for it to work, regardless of how the
environmental variables are set. In one of these cases, C was not even
the root drive, but proj would still not function unless it was at
c:\proj

So if you haven't already tried this, make sure that you have your
proj folder at c:\proj

I also see that in your getcapabilities link, some of the epsg codes
do not have 'epsg' capatilized .... try  'EPSG:xxxx' instead of
'epsg:xxxx'. I think I've seen a couple messages on the list where the
newer versions of mapserver are fussy about this.

I hope that helps,
Ken Lord
Vancouver BC



On Sun, 2 Jan 2005 13:17:03 +0100, Arnulf Christl
<arnulf.christl at ccgis.de> wrote:
> Hi,
> sorry I postet a wrong link. The problem can be seen here:
> http://www.mapbender.org/testbed.html
> I just added a box where the projection can be changed on the fly. Zoom
> in to below 1:50000 and switch to WGS84 and everything looks fine, the
> geometries from both servers overlap perfectly. Switch to GK3
> (EPSG:31467) and there is that offset.
>
> Arnulf.
>
> Arnulf Christl wrote:
> > Hi,
> > we experience a strange offset when overlaying the same data as WMS maps
> > with MapServer versions 4.0.1 and 4.4.1.
> >
> > *4.0.1 server*
> > Windows 2000: SP4
> > IIS: 5
> > proj: came with 4.0.1
> > gd: came with 4.0.1
> > gdal: came with 4.0.1
> > Cap URL:
> > http://wms.ccgis.de/umn/bin/mapserv.exe?map=d:/umn/germany.map&SERVICE=WMS&REQUEST=GetCapabilities&VERSION=1.1.0
> >
> > Data: local shape files in EPSG:4326 projected to EPSG:31467
> >
> > *4.4.1 server*
> > FreeBSD: 4.10
> > Apache: 1.3.33
> > proj: 4.4.9
> > gd: 2.0.33
> > gdal: 1.2.1
> > Cap URL:
> > http://wms1.ccgis.de/cgi-bin/mapserv?map=/data/umn/germany_demo/germany_demo.map&VERSION=1.1.1&REQUEST=GetCapabilities&SERVICE=WMS
> >
> > Data: the same shape files as above (WGS84) but dumped to
> > PostgreSQL/PostGIS (and also projected to EPSG:31467).
> >
> > The problem does not seem to result from MapServer but from proj?
> >
> > You can have a look at the problem here:
> > http://www.mapbender.org/demoserver.html
> >
> > Zoom in to a scale of 1:100,000 or less to see the post code areas. They
> > overlap with an x-offset (north):
> > in northern Germany 190m
> > in central Germany 145m
> > in southern Germany 100m
> >
> > The y-offset (east) is:
> > in western Germany 45m
> > in eastern Germany 125m
> >
> > That resembles a lot to a datum shift which we stumbled accross (years
> > ago) when reading GPS EPSG:4326 WGS84 data directly into the database
> > and overlaying it with Gauss-Kruger EPSG:31467 (Bessel projection).
> >
> > What has been changed and what impact does it have on projects which
> > overlay other data?
> >
> > Best regards, Arnulf.
> >
>