[Routing] generalized routing format - pre-computation

[Marcus Wolschon]

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Nic Roets schrieb:
> During rebuild, gosmore only mmaps the wayType data which is
> roughly 1GB. During one stage, it iterates through the node data
> and update the wayTypes they point to so that bounding boxes can be
> computed.
>
> Nothing stops you from adding code to that stage that will test if
> each node falls inside a polygon (e.g. place) and then modify that
> way.
>
> I don't believe that writing software for adjusting speeds for
> built-up places is worth all the effort. Reasons : * Place
> boundaries can't be surveyed by OSM members. Can only be guessed
> from aerial photos or imported from other sources.
On every road (that's the points where it matters) there is a sign
when you enter or leave a town.
> * Applies to few countries.
There are countries without different general speed-limits inside and
outside towns?
> * This extra info will seldom make a substantial difference in the
> route proposed by the routing system, because all the roads will
> typically go through the built up place.
Very often I see rings of roads around a town, to divert traffic.
Such a road being a primary-road  is longer then the primary-road through
the town but it is faster since you are allowed to drive at 2x the speed
and get 3-4x the actual speed since there are no traffic-lights at all.

I guess this makes for a very high difference in a significant number
of cases.

Also think not only of the routing itself but the projected ETA. If
will be horribly wrong
without differentiating between roads in cities and outside.

Marcus
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