[OSM-talk] Databases?

Andy Allan gravitystorm at gmail.com
Wed Oct 15 16:18:11 BST 2008

On Wed, Oct 15, 2008 at 3:53 PM, Joseph Gentle <josephg at gmail.com> wrote:
> Hi!
> I've been taking a look at the software stack and (especially with the
> intermediate XML formats) I can't help but feel that we could
> represent the map data in a much more efficient format - eg a
> quadtree.

OSM data is already represented in a variety of application-specific
formats. The xml structure is just for interchange, it's expected that
it can/will be converted before use by e.g. renderers, routing engines

> With the right data structures, it should be possible to
> render maps on client side in realtime. Maps are far less complex
> graphically than most 3d games; and they work just fine.
> So how good is postgis?

It's good, for various defininitions of 'good'

> Does anyone know if its performant enough for
> real-time map rendering? Can it do level-of-detail stuff ("fetch all
> data in europe with at least city level significance")?

I'm not sure exactly what you've got in mind, but it's fast enough to
render large areas of maps in sub-second intervals using mapnik, at
least. And it does spatial queries, so you can ask for all data in
Europe, and apply filters and so on.

> Has anyone tried making better data representations?

'Better' is dependent on what you're trying to achieve, but there are
certainly many 'different' representations in use in different


More information about the talk mailing list