[OSM-talk] An open letter to OSMF board members.

[Hartmut Holzgraefe]

On 06.06.22 14:35, ndrw6 wrote:
> but historically any changes to these tables they were difficult to deploy

to get even more off-topic: the "historically" part needs to be stressed 
here. When you have enough storage space to share you can do an 
osm2pgsql import using --hstore-all --hstore-only and then add views 
that present the imported data with "virtual" columns as individual 
styles expect.

I copied this approach from the German fork of the CartoOSM style, and 
I'm able to render some 30+ different base styles and almost 20 
different overlays from a single osm2pgsql import that way.

Whenever a specific style adds a new column I can easily recreate the 
views without having to re-import the actual tables.

This requires some 1TB of disk space for the hstore-all data plus 
indexes for a full planet database, but that's not an unrealistic 
storage side for any serious server anymore I'd say ...

 > The style is global, which mean it does not adapts to regional 
tagging conventions.
[...]
 > However, the same zoom level means very different things in Norway 
and in Singapore.
[...]
 >  A small object in the middle of the field can by a landmark, yet in 
the middle of city centers we want to be much more selective

now here things get more interesting ... here some meta data like 
"population density" (would most likely require an external data source, 
although some guesses could be made from building and road density?) and 
"POI / feature density" could be added as an extra data source that 
could be folded into SQL queries or with a little extra code work even 
into Mapnik itself?

And no, I don't have a clear concept or plan for this, just 
brainstorming for now ...

-- 
hartmut