[Routing] Getting A* to prefer Motorways

[Frederik Ramm]

Hi,

> Are there any plans to specify how to tag turn-restrictions
> and house-numbers yet? With the upcomming relations this
> was supposed to become possible and I can't wait to add
> support for both.

One other thing: 

How do you intend to do turn restrictions in A*? The basic algorithm
will never re-visit a node it has already processed, right? 

Imagine the graph (fixed-width font please)

      C
     /
A---B
     \
      D
     
With turn restrictions, it may well happen that the route

A-B-C

is not allowed, while

A-B-D-B-C

is valid. But A* will never use the D-B step in the above example if I
am not mistaken. 

A reasonably simple solution I could think of would mean that the
graph be modified by introducing pseudo nodes and edges:

      C
       \
A---B   B'
     \ /
      D

But I would almost guess that this introduces a truckload of problems
somewhere else... surely a problem that has been solved in literature
somewhere?

Bye
Frederik

-- 
Frederik Ramm  ##  eMail frederik at remote.org  ##  N49°00.09' E008°23.33'