[Talk-GB] reprojected NPE

orders2008 at sheerman-chase.org.uk orders2008 at sheerman-chase.org.uk
Thu Apr 10 10:15:42 BST 2008

> Yep, standard Google-like spherical Mercator tiles. They're at
> http://richard.dev.openstreetmap.org/npe/z/x/y.jpg
> where 'z' is 14 only at the moment, and x and y are Wales! (But growing.)
> Is there some way in which JOSM can display these tiles?

I am not sure but if JOSM was set to Mercator projection and a WMS  
server was created to return the tiles, it might be possible?

The main unknown (for me) is the projection of the WMS tile. For  
example, the lat and lon is not constant along the tile edges in  
Mercator. When JOSM requests a tile, does the bbox argument refer to  
the Top/Left and Bottom/Right corner lat/lons or some other method?

Once this is known it should be possible to create a Mercator NPE WMS server.

The alternative is do it in EPSG:4326. Since landsat is in this  
projection, it might be more consistent for JOSM without having to  
change projections all the time. This is the method I have implemented.


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