[OSM-dev] Compressed vector tiles with mod_tile?

[Peter Körner]

Hi

Am 04.11.2012 05:06, schrieb Kai Krueger:
> Overall this works very well in combination with e.g. KothicJS[2].
> However, as text based json is not very space efficient, Cover stores
> the json compressed in the metatiles.
>
> Mod_tile can't yet natively deal with this and doesn't automatically set
> the HTTP header Content-Encoding: gzip and I'd like to fix this.
Just a thing I stumbled across the other day:
http://code.google.com/p/protobuf-js/

It's a really small library but it could save us, together with some 
tricks, a lot of the GeoJSON-overhead. Possible tricks could be the 
mentioned Transfer-Encoding: gzip, using Integers for the Coordinates, 
store only the difference to the prev. coordinate, using a stringtable 
-- pretty much what the osm.pbf format useses to make our files smaller.

Peter