https://bugzilla.wikimedia.org/show_bug.cgi?id=33980
[email protected] changed: What |Removed |Added ---------------------------------------------------------------------------- CC| |[email protected] --- Comment #19 from [email protected] --- The coastline data is derived from two sources. 1) Natural Earth and 2) post-processed OSM data The natural earth data is a static data set that is probably only updated every couple of years. In the osm stylesheets it, is only used for very low zoom renderings of the entire earth, where precission doesn't matter. I think using natural earth still stems from a time when OSM didn't quite trust its own source of coast lines and didn't want tiny mistakes in the coast line propagating into large issues on a global scale. For the majority of the zoom levels the style sheets use osm coastline data that is post processed into shape files for better performance during rendering. It generates closed (and partly simplified) polygons out of the individual coastline segments. I think it takes a couple of hours to do the post-processing, as e.g. recreating a closed polygon out of the full resolution European/Asian coastline is a somewhat intense task. The toolset to create these coastline shapefiles are all open, and so it would be possible to build them locally. However, as far as I am aware no one has ever complained that the load from downloading the coastline files has been excessive. So I wouldn't worry for now if you pull those files from the upstream locations. Particularly not if you run it through a caching proxy (that caches such large files). That said, the current main OSM style sheet toolchain has changed somewhat in the past month ( https://github.com/gravitystorm/openstreetmap-carto ). Instead of writing the unwieldy mapnik style sheet xml by hand, they have moved over to a CSS based map style language (carto) that is then compiled (by a node.js based compiler) into the actual mapnik style sheet xml. In this process the style sheet has also moved over to a slightly different set of coast line files, which uses a more efficient tool-chain to creating those shapefiles. Those files now live on http://data.openstreetmapdata.com/ and the script https://github.com/gravitystorm/openstreetmap-carto/blob/master/get-shapefiles.sh downloads all the relevant files. I haven't yet updated my PPAs to use the new style-sheet, but I am hoping to do that soon. I'll try and do it sometime this week. But as I intend to put the pre-compiled mapnik xml style sheet into the packages rather than the carto source (to avoid the node.js dependencies) nothing much should change from a tile server admin's point of view. -- You are receiving this mail because: You are on the CC list for the bug. _______________________________________________ Wikibugs-l mailing list [email protected] https://lists.wikimedia.org/mailman/listinfo/wikibugs-l
