[OpenLayers-Users] EPSG:4326 overlay EPSG:900913 as WMS

[Christopher Schmidt]

On Wed, May 13, 2009 at 04:56:26PM +0200, Dipl. Inf. Carsten Eider wrote:
> Hi list,
> 
> as far as i understood by reading lots of mailings within this list and
> spending time on walking through different openlayer pages
> there seems to be no solution for using a
> wms in epsg:4326 on top of a google EPSG:900913.

Correct. All raster layers in OpenLayers must be in the same projection.
Browsers can not reproject images. Therefore, if you wish to use a
raster layer, it must support the projection fo the base layer -- in the
case of google, that's spherical mercator.

> I tried lots of ways to tell my wms-layer to be requesting in EPSG:4326,
> but none worked.
> my problem ist, that the layers i want to use come from governmental
> servers not offering EPSG:900913
> but EPSG:4326 or EPSG:31647.

Then you can't use them on top of Google Maps without making yourself a
reprojecting service. You can use MapServer as a WMS server to 'cascade'
-- load and reproject, in this case -- from the remote server. This
would mean you would talk to your own MapServer, which would then talk
to the government provided WMS.

> Can anyone comfirm this situation or show me a solution?

Yes, I can confirm that you are correct.

> Are there any Reprojection-Services available?

MapServer can act as a reprojection service.

Regards,
-- 
Christopher Schmidt
MetaCarta