[OSM-talk] This side, that side

[Robert Hart]

>
>
>
> It's better to use "left" and "right" - the renderer knows the direction
> of
> the segment, and is able to tell the difference between the "left" side of
> the segment and the "right" side of the segment.
>
> And it's unambiguous - suppose we use north and south, and we have a
> perfectly
> vertical segment....
>

Or more likely, suppose we have a circular way, or an arbitrarily curved way
then both sides face in all directions.

or a way that is very slightly off north south to the east, then adjusted to
be just off north south to the west, suddenly left and right have swapped.

or imagine the data is being preprocessed to project it to another
coordinate system, then what?

I think this is just a small part of a much harder problem though. At the
moment we are happy adding lone nodes for post_box, post_office,
place_of_worship, pub, etc., but I can't help but feel like this information
should be associated with the road the amenities are actually on.
Additionally, as we seem to have an ever expanding set of taggable items, I
can see a day when a typical main road has 20 or 30 lone nodes, next to it,
that would need to be moved if the road itself is adjusted.

No idea of a solution though.
-- 
Robert Hart
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