[OSM-dev] Why no curves in map data?

[Martin Koppenhoefer]

2009/3/15 Stefan de Konink <stefan at konink.de>:
> Udo Giacomozzi wrote:
>> Of course I realize that now the OSM data format can't be extended to
>> curves without breaking existing renderes and tools...
>
> You can extend it to NURBS without breaking tools ;) Think about the
> control point approximation ;) So every embedded device that isn't fast
> or doesn't have a fpu will use the ugly linear version, while any other
> tool will use the weight associated with the line thus has a pretty
> version of it all.
>
>
> Stefan

I'm quite familiar with the use of NURBS ecc. but want to point you to
another fact: curves in streets are not designed completely "free" but
follow in nearly all cases some basic rules, that is: they are all
tractrix.
http://en.wikipedia.org/wiki/Tractrix

So when thinking about implementing curves, think first of
implementing this type of curve that is used to design streets.

Martin