Comment by pietervdvn | Hacker News Reader

Comment by pietervdvn | Hacker News Reader

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No. OSM could _not_ have grown this big if we had layered everything. Far from it - the big power of OSM is the integration of all those 'layers'.

Furhtermore, layering would needlessly complicate everything.

Take a railway crossing for example. Should it go in the layer "railways", in the layer "roads" or in the layer "railway crossings"? Should we make a new layer for paths, so that they are separate from car-only roads? What if something changes? How should an object be moved from one layer to another?

What with benches that double as a piece of artwork? What about this place that is a boardgame shop, a café and a social project for mentally disabled people?

What if a river doubles as administrative boundary?

If you want to extract data that is relevant for you, there is overpass-turbo.eu for this, where you can write a precise query and only get and download the data you need.

I certainly agree it wouldn't have grown as big as it is with a less pragmatic approach. Entirely.

But there must be a moment when some simplicity or pragmatism must be exchanged for scalability.

Layering is one option. While indeed railroads and roads probably want to be on the same layer, opening hours or pavement need not be. I'm not saying a node may only ever be on one layer. They can easily be duplicated over layers. Just like at boundaries of geographical chunks, (i.e. over the borders of luxembourg.osm.pbf) there are (tens) of thousands of nodes that also appear in Germany, Belgium, the Netherlands once even.

This 'splitting up in layers' gets done by third-parties, such as geofabrik.

Geodata is more complicated then just 'layering' everything. Also, making an entire ecosystem change is a huge effort

I know and I agree.

But "making an entire ecosystem change being a huge effort" does not prove that it's unnecessary. It just says that it is hard.

I've never seen the OSM community back away from projects because they are "hard". And the moment this community starts doing that, it can just as well abolish oneself, IMO.

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