[OSM-talk] Should Bridges be independent of their ways?

[Lester Caine]

Richard Mann wrote:
> If we were just gathering data for routers, we would map every lane as a 
> separate way, with relations for moving between each pair of adjacent 
> lanes. If we were just gathering data for rendering a single-scale 
> street map, we'd add tags to a single way, and probably not bother with 
> lane info.
>  
> I think routers ought to be able to cope with a single-way structure 
> with extended tags. I think renderers would struggle (even more) to 
> produce a good-looking multi-scale map if the data is held as multiple ways.
>  
> I think the most generally-usable structure is a single way with lane 
> info. This could be done with tags (and probably needs to be, to start 
> with), though you might hope that editors would find a way of presenting 
> it so that it looks like a set of parallel ways with tied nodes.

Simple answer to that BULLSHIT.

The only way to produce fine detail maps is with the correct 
information. Adding a footpath at the side of a road which along the 
length of the road meandering from one side to the other, is adjacent to 
the road in places, or separated by a grass verge, or isolated by bushes 
can not easily be managed by tags added to the road. Add the pull off 
for a bus stop, with the changes in the path of the pavement for that. 
The changes as a footpath merges with other obstructions at road 
junctions ... and so on. Getting the renderer to guess what the real 
situation is even with quite complex tags does not make sense.

A single way simply does not work at the micro level unless you make the 
tagging so complex that only a computer could understand it? And it 
would have to have distances as part of the tags so you know how far the 
edge of the path is from the arbitrary center line of the base way.

I *AM* coming to the view that we perhaps need another layer of 
information? AT the macro level it is simply a way, but at the micro 
level a way would consist of all the detail necessary to accurately map 
the reality on the ground? But whether the macro view would need the 
'path=left', 'path=both' information as tags is questionable?

-- 
Lester Caine - G8HFL
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