[OSM-talk] Collected Way support

[Richard Mann]

I agree that it's a real issue. It's a pain assigning all the short ways to
a relation (which is what I've been doing this afternoon), or adding
information along a route (ie the number of tracks on a railway). However,
when I read the proposal, I could see that trying to use relations would
generate a fair few problems - which haven't been addressed.

But I realised that the problem could be much reduced if "temporary"
alterations to the tags could be done, which they can for individual nodes
(eg barrier=gate). And if they can be done for nodes, they can be done for
single segments, if the data model is right.

It doesn't completely solve the problem, but it could reduce the problem
significantly (at least on main roads like the one near me that used to be
called the seven bridges road...)

Richard

On Thu, Jul 9, 2009 at 4:31 PM, David Groom <reviews at pacific-rim.net> wrote:

> ----- Original Message ----- From: "Richard Mann" <
> richard.mann.westoxford at googlemail.com>
> To: "Talk Openstreetmap" <talk at openstreetmap.org>
> Sent: Thursday, July 09, 2009 3:51 PM
> Subject: Re: [OSM-talk] Collected Way support
>
>
>  It looks too complicated to me.
>>
>> Given that certain tags apply to ways but not nodes, would it not be
>> possible to imply some meaning by attaching bridge=yes+layer=1 to a node
>> on
>> a way, to mean the segment between this node and the next?
>>
>> Then the way wouldn't need to be chopped up in the first place.
>>
>> Richard
>>
>
>
> Richard
>
> This is not some theoretical point, it's what is happening to the data, and
> ways ARE becoming very fragmented
>
> Consider the situation below, which actually is fairly simple only, in
> practice where more bus routes occur, speed changes, the way goes goes over
> a bridge etc...the way gets split into many, many more parts.
>
> A - G, say "High Street", starts off as a nice simple linear way,
> D - J  is a road called "Long Way"
> B - H and C - K are footpaths
>
> at E the speed limit on High Street changes from  say 30kph to 40 kph.
>
> a bus route travels from A - D along High Street, but turns on to Long Road
> along D - J
> a long distance walking route uses footpath  K - C part of High Street C-
> B, and then continues along footpath B - H
>
>
>       H                J
>        |                 |
>        |                 |
>        |                 |
> A------B-------C-------D-------E--------F--------G
>                 |
>                 |
>                 |
>                 K
>
>
> Currently in order to map this simple situation in OSM way A - G has to get
> split in to 5 ways.
>
> A - B, B- C, C- D, D - E, and E - G
>
> It's necessary to split the way at B & C, so part B - C can become part of
> a relation grouping K - C, C - B, and B - H all for the long distnace route.
>
> It's necessary to split the way at D so the relation for the bus route
> doesn't include parts D - G
>
> It's necessary to plt the way at E so the spped limit can change
>
> David
>
>
>
>
>> On Thu, Jul 9, 2009 at 3:17 PM, David Groom <reviews at pacific-rim.net>
>> wrote:
>>
>> For various reasons, for example the need to put different max_speed tags
>>> on
>>> different parts of a way, the need to split ways so individual parts can
>>> become part of a relation, etc, even "simple "  linear ways are becoming
>>> very fragmented.
>>>
>>> I was just wondering what the current state of client support (renderers,
>>> editors, routing programs etc) is for collected ways [1].
>>>
>>> David
>>>
>>> [1] http://wiki.openstreetmap.org/wiki/Relations/Proposed/Collected_Ways
>>>
>>>
>
>
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