[OSM-talk] Advanced Relationships

[Frederik Ramm]

Hi,

>>> Sure, but we should also have a serious discussion about what to do
>>> about the street number data that already exists in the DB. Currently
>>> segments are the natural place to put such data and you're not
>>> providing a useful alternative...

There are 120 instances of street number data in the whole planet file.

> Firstly, we're not talking about one street number, but billions of
> them, every street has many. Adding a node for each is a complete
> waste of time, since nobody actually cares about the exact location of
> the letterbox. For routing all you want to know is which segment the
> number is on and possibly left or right.

This is not true. A segment could span a kilometre or more and thus is 
not a natural bearer of house number data.

The segment as we know it is just a primitive building block for ways 
and should not be used to attach information to it: People regularly 
change the shape of a way by moving its nodes, inserting or removing 
segments, or splitting a segment in half to attach another way they just 
mapped. All these operations will render house number information 
attached to segments useless. Also, if you have a curved way between two 
nodes, approximated by 5 segments, how do you want to add information 
about house numbers there?

> there has to be a way to say: this <whatever it is> is
> between node A and node B on this way.

I agree that it would be nice to have something like this. (GDF, for 
example, has a sophisticated way of describing house numbers.)

But segments in their current form (and in the way they are treated by 
users and editors) are not a suitable vehicle for this.

Bye
Frederik

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