[Talk-ca] [Fwd: Re: Address ranges]

[Richard Weait]

Oh, how silly.  I responded to Steve alone, rather than the list.  Here
you go.


-------- Forwarded Message --------
> From: Richard Weait <richard at weait.com>
> To: Steve Singer <ssinger_pg at sympatico.ca>
> Subject: Re: [Talk-ca] Address ranges
> Date: Sat, 21 Mar 2009 22:00:31 -0400
> 
> On Sat, 2009-03-21 at 21:21 -0400, Steve Singer wrote:
> > I'm starting to think about how we might want to import address range data 
> > from Geobase/Statscan into OSM.
> 
> Hi Steve, (and all)
> 
> I would love to see the address data imported.  
> 
> Everything that you said sounds good.  I think that the address nodes
> must be off the road.  
> 
> My understanding of Karlsruhe schema is imperfect, but I believe that
> interpolated addresses require a way rather than two nodes?  If so, and
> if we address a "curvy" block, then the address-interpolation-way may
> cross the block twice or more.  I don't know if that is fatal to
> addressing, but it would look suboptimal.  Given this situation, is it
> possible to add the interpolated way by: 
> 
> duplicating the road / block
> clip four meters from each end
> offset from the road by two meters
> apply address interpolation data as appropriate.
> 
> Repeat for other side of road
> 
> This might give us a map like:
> 
>          ! H !
>          ! H !
>   -----    H    -----
> ===========#===========
>   -----    H    -----
>          ! H !
>          ! H !
> 
> So the roads look pretty normal and the addressing ways look like
> sidewalks that never meet with each other.  We will need to adjust the
> distances to something sensible.  (How acute an angle do addressed road
> meet?)  
> 
> This does triple the db size (node and way count) for each road with
> address info.  But it's just Canadian road data, it's not like we're
> tripling the size of the US data....
> 
> Wonderful news that you are looking at this.  
> 
> Best regards,
> Richard
>