Hello everybody, I am sorry for answering so late. Thanks for the motivating answers.
>> 1) Shoud it be WMS or WFS service? > Andrea Aime wrote: > It depends, with vector output there's always a grey area. As a rule > of thum, if the output has any styling (it has to contain color, line > width, filled polygons and the like, and be driven by an SLD) then > it should be a WMS output format, since there is no concept of > styling in WFS. Ok, I will do it as a WMS service then, since I the plan ist to deliver styled maps. > GeoServer already has two SVG based output formats, one that > is based on Batik and that supports SLD almost fully but it's kind > of slow, and another one that supports very limited styling but > is faster. > I don't know anything about these SVG profiles for mobile hardware, > but I guess you'll need total control over the output, so I suggest > you look into the one that does not do full styling, and adapt > it to your needs. The classes can be found in the WMS module, > org.vfny.geoserver.wms.responses.map.svg package, and in particular > the low styling high performance classes are SVGMapProducer and > EncodeSVG, whilst the full styling lower performance is > SVGBatikMapProducer. I started wit the cloning and adapting the SVGMapProdcer.java, EncodeSVG.java and added my Render so it can be choosen via the WebInterface as the SVG-Renderer. >> 3) my biggest concern using geoserver is that I am afraid I can't >> make use of the PostGIS function AsSVG() <http://svg.cc/pg/assvg/> >> where I could optimize output by setting relative coords and limit >> precision. > > True, a WMS output format receives a MapContext definitions, that > do in turn have FeatureSource object. A good output format must not > make assumptions on the backend, and the PostGIS data store won't > allow > you to make use of that function either. > Then again, you can use the GeoTools Decimator class to perform > a simple on the fly generalization (that class assumes you're using > a special coordinate sequence class for your geometries, we can > talk details about this in a separate mail). Okay so I guess I will just have to use external tools to make some nicer SVG Data instead of letting PostGIS make all the work, which I thought would be faster than doing it in Java. PostGIS also has the Simplify function which does the generalization. It would be nice, if we could talk about the Decimators generalization in separate mail as you suggested Andrea. It sounds as if I also could use this class to convert the geo data to my local screen device coordinate system, so the client does not neet to do calculations? >> 4) For my purpose I guess I would use SVG Basic instead of Tiny >> because Tiny profile does not support textpath element which is >> nice for street names. >> 5) A gzip output would also be nice to reduce the file size > > This is handled automatically by GeoServer already. There is a > filter installed in GeoServer that compresses text based outputs > on the fly. You just have to add the svg mime type (image/svg+xml) > to the list of compressed types, look into web.xml. Great, works fine. >> 6) Since I need a lot of map data to test navigation I would like >> to import OSM data (OpenStreetMap) into the PostGIS database. I >> know the tables of OSM are a mess I have to correct myself. The data povided by GeoFabrik is pretty nice. When I used a tool osm2psql it imported the whole table structure. THe GeoFabrik data is very simple. Cheers Ivo ------------------------------------------------------------------------- This SF.Net email is sponsored by the Moblin Your Move Developer's challenge Build the coolest Linux based applications with Moblin SDK & win great prizes Grand prize is a trip for two to an Open Source event anywhere in the world http://moblin-contest.org/redirect.php?banner_id=100&url=/ _______________________________________________ Geoserver-devel mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/geoserver-devel
