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

[Colin Marquardt]

2009/3/15 Martin Koppenhoefer <dieterdreist at gmail.com>:
> 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

I thought they were http://en.wikipedia.org/wiki/Clothoid ?

Cheers
  Colin