Re: [OpenSeaMap-develop] Sports layer

[Gabriele R. <gab...@un...>]

On 12/14/2014 10:27 AM, yvecai wrote:
> For a world-wide layer, pre-rendering is not really an option.
> 
> I would also go for the postregsql / mapnik / renderd /mod_tile / apache 
> solution. For more information on how to set this up, see 
> http://switch2osm.org/.
> 
> I took the time to make a mapnik style for whitewater sports, see here:
> https://github.com/yvecai/mapnik-opensnowmap.org/tree/master/watersports-overlay
> There is the tilemill project here: 
> https://github.com/yvecai/mapnik-opensnowmap.org/tree/master/watersports-overlay/TileMill_ww-style
> 
> I also setup a data extracting process similar to that I use on 
> Opensnowmap.org. Basically, I update a OSM planet file (only 50GB) 
> everyday before filtering it with osmfilter. It's cheap and easy, then I 
> put in postgresql only the elements I want. See 
> https://github.com/yvecai/data-opensnowmap.org/blob/master/tools/02-filter-ww.sh.
> Of course this step can be replaced by an Overpass query to obtain the 
> osm file.
> 
> I'm running the process on Opensnowmap.org dev server to share the result.
> 
> Of course I can help if there is some space and will on openseamap.org 
> server to revive the sport layer, let me know.

I decided for an analogous setup (also creating the Mapnik style file
with tilemill). At the moment, I just tried to replicate the output of
the old sports layer. I put everything in my repo at
https://github.com/roeger/openseamap-layer-sports. This is currently
limited to Austria.
As soon as Niko has the PostGreSQL available, I can adapt it to work for
the world.

One thing that might also be relevant for other layers: I did not assume
limited filtered data in the data base but the entire planet information
(because we plan to also render the base layer ourselves). To get good
performance of the renderer, it appears to be important to use very
specific SQL queries so that Mapnik does not have to process unnecessary
data.

Unfortunately, I cannot show you a link to a demo installation because I
only have the Database running locally.

Cheers,
Gabi