[OSM-dev] Obtain SLD style for osm

[Dane Springmeyer]

On Jan 26, 2010, at 8:05 AM, moataz Elmasry wrote:

> Hallo list
>
> 1- We are developing a GIS application using osm maps and a geoserver.
> My problem is that there's no reliable sld style for the osm maps.

Right, because it takes a serious amount of effort, care, and  
commitment to create and maintain styles as sophisticated as those  
behind many of the well know maps from OSM that use Mapnik.

> Is
> there a way to convert the mapnik style to SLD or does any of you know
> such a resource?
>

I've done this in the past with simple Mapnik XML (and also converted  
SLD to Mapnik XML) and it's not too difficult with a bit of XML work.  
I did it with python scripting but likely a better route would be XSLT  
transforms.

But, I would not recommend this route for the osm.xml unless you have  
a very keen attention to detail as many of the subtle styling  
parameters that make OSM maps look good are custom to Mapnik (and  
would also likely be custom "VendorOptions" in GeoServer). There would  
be great value to creating a mapping between these, but its not going  
to be an easy thing.

> Although the assignment states that we use geoserver as our wms map
> server and maps from osm, but I feel that its not a very smart idea to
> mix the two, what do you think?

Mixing WMS and OSM data in general when using complex styles is  
usually not the right approach, no matter what library you use to do  
the rendering because the size of the data and time it takes to render  
the styles is much better done using TMS (Tiled Map Service). This is  
the way that tile.openstreetmap.org works (using mod_tile), serving  
tiles that get cached for speed once they are rendered.

I would recommend using the existing OSM styles + Mapnik + mod_tile.

Dane