[OSM-talk] Wanted feature for API 0.7 ??

Dave Stubbs osm.list at randomjunk.co.uk
Tue Jun 9 09:31:30 BST 2009


2009/6/9 Nop <ekkehart at gmx.de>:
>
> Hi!
>
> Dave Stubbs schrieb:
>>
>> Which just tells you those aren't the "appropriate tags" of which matt
>> speaks.
>>
>> Careful selection of tags means that nothing existing needs to change,
>> unless it's to make life easier for the user by adding filtering
>> features.
>
> That is exactly the problem. When you add things that are not supposed to be
> visible by default, as they describe past or future objects, the items are
> there. And by no amount of tagging can you make them go away, that requires
> awareness of your tags and active filtering on part of all applications.
>
> Or can you please describe how an "appropriate" tag should look like e.g.
> for an object that will be torn down next year, so that it disappears from
> the map at the appropriate time without changing the renderers?
>

Umm.. you can't. And why would you want to?
It's a wiki. You can edit it.

highway=motorway
demolition_date=2009-09-01

then, on 1st September a mapper can come along, actually check the
thing /was/ demolished (possibly prompted by some clever application)
and replace with:

highway=demolished_motorway
demolition_date=2009-09-01 18:03:05+00

Anybody who wants to try to be clever can add knowledge of the
demolition_date tag to their renderer/router. Anybody who doesn't will
have the motorway disappear from their maps when they next update.

Same goes for construction...

highway=under_construction_motorway
construction_complete_date=2009-10-12

to

highway=motorway
construction_complete_date=2011-08-05

The unaware renderer will see the motorway when it gets an update. The
aware renderer will start displaying the motorway about 2 years too
early, although you can expect the mapper to have updated the expected
completion date by then as no doubt the political fallout of yet
another multi-million pound government overrun gets splashed over the
papers.

None of this stops the ways appearing in the editor, but as has been
mentioned, there's more than one reason why that could be a bad idea
anyway. This kind of thing comes under "unless it's to make life
easier for the user by adding filtering features".

Dave

PS. I'm not actually advocating those particular tags names, or even
saying they're a terrible idea, or that governments can't deliver big
projects on time :-)




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