[OSM-talk] Enabling communities to use OSM as a planning tool

[elvin ibbotson]

This topic reminded me of some thoughts I had about time-based  
tagging but did not pursue. I have a professional interest in planned  
features but a leisure interest in historic features such as ancient  
roads. The OSM database could include both these types of feature but  
for general purposes the map should only show what is there now, not  
what used to be there but has gone or what may be there in the  
future. My thought was that there could be a time-based tag which  
would show the time-span of a feature. It might be called 'epoch='  
and could indicate when a feature existed/will exist. Anything with  
an epoch which did not include today would not appear as standard,  
but a time-based viewer might allow users to 'scroll through time'  
seeing features appear/disappear as the viewer's epoch entered/left  
that of the features.

A difficulty is that there will usually be some uncertainty about the  
dates, so the tag grammar would need to take account of this.  
Sometimes the beginning or the end date will be unknown or there will  
be only the most approximate knowledge of a date, so the tag grammar  
must allow for various levels of accuracy and for incomplete epochs.  
One approach might be to use a grammar like from>to so a road due to  
open in December this year could be tagged epoch=12/2008> or an  
ancient track that fell out of use and disappeared in the 16th  
century might be tagged epoch=>C16. A feature that was known to exist  
for much of the 1700s but probably not before or after could be  
tagged epoch=C18 (implying from/to dates of 1700 and 1799) whereas a  
temporary path existing just for the duration of a construction  
project might be tagged epoch=12/03/2006>23/12/2006.

Features with no epoch tag (like pretty much everything in the map  
now) would default to 'now' and if the viewer left the present epoch  
to look back at past features or forward to planned features would  
show these against a dimmed backdrop of the present-day map. Such a  
viewer could use the standard bitmap tiles for the present-day  
background but would need to use vector data from the database for  
past/future features.

elvin

> From: "Andy Robinson \(blackadder-lists\)" <ajrlists at googlemail.com>
> Date: 4 June 2008 08:54:53 BDT
> To: <talk at openstreetmap.org>
> Subject: [OSM-talk] Enabling communities to use OSM as a planning tool
>
>
> Lat night I attended a steering group meeting for my local Connect2  
> [1]
> project in north east Birmingham [2]. One of the things that the  
> group could
> benefit from is rapid response on mapping so that it can discuss route
> options for the new cycle/walk routes to be built under the  
> project. OSM is
> the logical tool to use for this process and I'm keen to show what  
> we can do
> with the OSM data and the OSM platform to support the work. At the  
> moment
> everything is done as overlays on Ordnance Survey 1:10,000 mapping,  
> not an
> ideal way to integrate ideas into the existing infrastructure.
>
> This brings me to the point though. Currently we map physical  
> features as
> they exist and in some cases the alignment of known construction,  
> what we do
> not do is use OSM as a planning tool. What are people's views on  
> this? It
> seems that OSM is an ideal platform for enabling communities to  
> develop
> their own planning, without having to rely wholly on the GIS  
> department of
> their Local Authority, it also makes publishing ideas so much  
> easier without
> the encumberment of the OS licence restrictions.
>
> Anyway I'm going to give it a try here and come up with some  
> logical tags so
> that the data does not get rendered by default unless a custom  
> style sheet
> is deployed. But maybe the easiest was is to have the renders  
> ignore data
> that carries a specific tag. planning= perhaps?
>
> I'd welcome some feedback.
>
> Cheers
>
> Andy
>
> [1] www.connect2.org.uk
> [2] www.connect2birmingham.org
>
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.openstreetmap.org/pipermail/talk/attachments/20080604/ed46f097/attachment.html>