[OSM-dev] How to get offline maps of a large area in reasonable time?

[Ivo Brodien]

Hi,

>> I started trying  the first options but it is way to slow. Probably
>> because some never requested tiles also have to be rendered on the
>> server first?
> Exact. I don't think it's a good idea anyway without asking the  
> server admin.
> That will put a constant load on the server and prevent other users  
> to have a
> responsive answer to their browsing.

I just found this similar post:

http://lists.openstreetmap.org/pipermail/dev/2009-March/014331.html

I guess I should go with rendering tiles on my own.

>> I already have the planet file
>> loadet into a PostGIS-DB
>> Does anybody know how many GB the whole world is? Or Germany?
>
> Doesn't your Operating System support "display disk usage" of a  
> directory ?
>
> Maybe I don't understand your question...
>
> I'm working on the europe extract and I count around 3 times the  
> uncompressed
> osm file or 30 times the compressed one (using osm2pgsql in slim mode)
> but dispending of your method it may vary very much.
>
> Or you mean tiles on disk usage ?

yes, that is what I meant. The size for the tiles. I could also  
calculate it myself, assuiming an average files size of 13kB per  
256x256 png


>> How long would it take to render on a quite powerfull desktop- 
>> machine?
> 3 seconds for zoom 0
> 3 times the age of the universe at zoom 30
>
> That all dispend on the max zoom you want.
> As a rapid guess on germany at max-zoom 16 I bet it would take  
> around 2 days

I would want it for zoom up to zoom level 17.

>
>> Or are there any other ideas on how to get such a big amount of data?
>
> See why almost no-one renders in advance every thing up to zoom 18 by
> reading :
> http://wiki.openstreetmap.org/wiki/Mod_tile
> http://wiki.openstreetmap.org/wiki/Slippy_Map


I know why it does not make sense to render everything in advance, but  
in my case I need the data instantly because the map will move very  
fast.


Thanks a lot for your help. I guess I will just try Mapnik. Does  
anyone know if there is a mobile style for Mapnik which looks similar  
to the Cloudmade mobile style?

-Ivo

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