Hi Andreas, The WMS server does not have formal support for loading map styles via XML. Your attempt to get it working looks remarkably close, but in general I would guess you running up against the limited ability to work with symbols using the mapnik python bindings.
As an issue itself, you could file a ticket on trac.mapnik.org on what needs to be added to the boost::python bindings. As far as the general issue of how to use the load_map() function with the WMS server, take a look at: http://trac.mapnik.org/ticket/129 Perhaps you can contribute to testing and refining this approach of building the load_map() function into the OGCServer code itself? Cheers, Dane On Oct 14, 2008, at 10:51 PM, Andreas Theofilu wrote: > Hi list, > > I've managed to setup a WMS server based on Mapnik. I'm able to read > in the > XML-Script for OSM data and I get a nice map out (code is at > http://www.theossoft.net/mapnik/worldMapFactory.html). The > linked code get it's raw data from a postGis database, where I've > stored > Europe. (for the complete XML file look at > http://www.theossoft.net/mapnik/osm.xml) This works, but there is a > layer > called "minor-roads" I'm not able to read in completely correct. The > roads > are too fat and this makes the map look ugly (look at > http://www.theossoft.net/mapnik/map.png). > > I assume, It's not possible to copy the symbols correct by doing: > > for sym in r.symbols: > rule.symbols.append(sym) > > The above code is mostly correct, but maybe not for the following > part of the > XML file: > > <Layer name="minor-roads" status="on" srs="+proj=merc +datum=WGS84 > +k=1.0 > +units=m +over +no_defs"> > <StyleName>minor-roads-casing</StyleName> > <StyleName>minor-roads-fill</StyleName> > <StyleName>aerialways</StyleName> > <Datasource> > <Parameter name="type">postgis</Parameter> > <Parameter name="host">localhost</Parameter> > <Parameter name="user">username</Parameter> > <Parameter name="dbname">gis</Parameter> > <Parameter name="table"> > (select * from planet_osm_line order by z_order) as roads > </Parameter> > <Parameter name="estimate_extent">false</Parameter> > <Parameter > name="extent">-20037508,-19929239,20037508,19929239</Parameter> > </Datasource> > </Layer> > > The rules for the styles "minor-roads-casing", "minor-roads-fill" > and "aerialways" are defined prior. > > I've read a lot about Mapnik and looked at the source and the > available > examples. But I was not able to figure out, how I can copy the symbols > correctly. I'm even not able to find out, what type of symbolizer > I'm copying > (line symbolizer, polygon symbolizer, ...). Is there an example > somewhere or > can anybody explain, how to do that? > > > Beside this I found out, that I have to define every style name as > a "wmsextrastyle" to be able to make the WMS server draw one layer > over the > other. Without this, I can only request one single layer. If I try > to request > more than one layer, and give no style names, I get the error: > > <ServiceExceptionReport version="1.3.0" > xsi:schemaLocation="http://www.opengis.net/ogc > http://schemas.opengis.net/wms/1.3.0/exceptions_1_3_0.xsd";> > <ServiceException> > OGCException: STYLES length does not match LAYERS length. > </ServiceException> > </ServiceExceptionReport> > > But simply registering the layers, allthough every style has a > propper name, > is not enough. I've to register the style names of the layer as > extra styles > to make the WMS server recognize them. To get more than one layer, > the styles > parameter on request must contain exactly one style name (if there > are more > than one, it doesn't matter which) for every layer I want: > > http://localhost/cgi-bin/wms?VERSION=1.3.0&REQUEST=GetMap&\ > LAYERS=water_areas,bridges&STYLES=water_areas,bridges&\ > FORMAT=image/png&SRS=EPSG:3395&CRS=EPSG:4326&\ > BBOX=16.254412,48.170568,16.375430,48.199311&width=800&height=600 > > Is this a bug? If not, it differs from other WMS servers, where I > can leave > the styles parameter blank. > -- > Andreas Theofilu > http://www.TheosSoft.net/ > > --==| Enjoy the science of Linux! |==-- > _______________________________________________ > Mapnik-users mailing list > [email protected] > https://lists.berlios.de/mailman/listinfo/mapnik-users _______________________________________________ Mapnik-users mailing list [email protected] https://lists.berlios.de/mailman/listinfo/mapnik-users
