[OSM-dev] Slippy map way forward -- OpenLayers and/or Mapstraction?

[Christopher Schmidt]

On Fri, Jun 30, 2006 at 09:22:04AM +0100, nick at hogweed.org wrote:
> >I was wrong. http://openlayers.org/dev/examples/openstreetmap.html is an
> >example of that, but it clearly doesn't work. Roads which clearly cross
> >tile boundaries dissappear when they hit the boundary, roads are drawn
> >right through the millenium dome, etc. 
> 
> What happens at the moment with the OSM slippy map and renderer (and what has 
> always happened, I think) is as follows:
> 
> a) OSM slippy map takes in a bounding box in normal (non-Mercator projected) 
> latitude and longitude
> b) Internally (in the slippy map), the latitude is coverted to 
> Mercator-projected latitude in order to divide up the tiles evenly by 
> Mercator projection, so that the tiles won't be "squashed" by the poles

Yes.

> c) For each tile, the Mercator-projected latitude is converted back to normal 
> latitude and sent to the OSM renderer. This is because the OSM renderer 
> accepts a bounding box of "normal" (WGS84? not Mercator-projected anyhow) 
> latitude and longitude. (I thought that was standard? i.e. I thought WMS 
> servers accepted a bbox of regular latitudes and longitudes, not 
> Mercator-projected values)

So, where is 'the OSM renderer' in this case? Is there another URL (that
is not wbxrmod or whatever) which I can use as a backend service? From
your description, it sounds like this would essentially be a script
which converts my 'good' values for WGS-84 into 'bad' values, and passes
them to something else. Is the 'something else' accessible on the web?
If it was, then I think I would be able to at least get that displayed
correctly...

-- 
Christopher Schmidt
Web Developer