27 August 2010

MapProxy Project for Accelerating your WMS

There are a few Open Source WMS caching proxys that are freely available for anyone to download and use. GeoWebCache and TileCache have been the two leaders in the MapCache game for a while now. The problem with these is that they only output WMS-C which most WMS readers can't read. MapProxy can ingest WMS, TMS and KML thenspit it back out as a valid WMS service so that ALL modern GIS clients can read it.
I just setting up OSM into Tilecache as TMS.
From above information, I think I need mapproxy, if i want to turn the TMS into WMS


Features of MapProxy

MapProxy acts as a WMS, TMS and KML server. It does not render any data itself but delegates requests to other server. It stores all responses and reuses that cached data for further requests. It can requests data from WMS and TMS clients.
MapProxy supports:
MapProxy can:
  • accelerate existing WMS
  • reproject to other SRS (i.e. cache in EPSG:4326, requests in EPSG:31467)
  • combine individual map layers from different WMS services
  • hide the origin WMS servers
  • fill caches dynamic, in advance or both
  • add watermarks and/or attributions to all responses

Xiaoyu Guan (Sam)
I just found one great tutorial for rendering osm in custom projection.
The tutorial is locate at http://www.justobjects.org/blog/?p=45
It covers import raw data to PostGIS. and setting up Mapnik osm.xml with right projections.
Last but not least, how to setting up tilecache with mapnik.
then you can use seed tool from tilecache to cache all the layer in your own projections.
or you can try to rewrite seed tool from mapnik. but the tool is default for projection 4326. you have to modify the script.
There is some differences between these tools, the tool from mapnik or osm community is store all tiles in standard XYZ folders.
so you can render the cache via OL xyz layer.
The cache from Tilecache is stored in tilecache own name convention.The cache is not store in standard XYZ tiles.
You cannot render tilecache cache file viw OL default XYZ layer.  At least I tried and failed.
For more details, better check Just' tutorials.

Xiaoyu Guan (Sam)

17 August 2010

As you know, there is OSM SLD from FlorentDotMe.
Last time, I did not success for rendering osm data using the sld.
but this time, I made it.
Here is some screen dump from FlorentDotMe SLD.
I use original OSM data of Netherlands, projection 28992.
The import tools is osm2pgsql, then reprojection the whole database to 28992.

check attached images for more detail.

personally, the sld is quite good but not same quality as mapnik style.