Frederik Ramm wrote:
Time zones, in contrast, are
* orders of magnitude less useful than admin boundaries (most countries will
simply have one time zone for the whole country)
* not useful for mappers
* readily available in shape file form
so why map them?
Except that the currently available 'shape' files are totally useless near
boundaries putting whole towns in the wrong time zone! The 'boundaries' we are
looking for ARE in many cases the same as the political boundaries, so SIMPLY
adding a timezone tag to these boundaries is all that is required ... except
where there are specific variations in which case these NEED to be mapped. What
we are currently pushing is that OSM provides the base for that information
against the TZ database.
The current arguments on the TZ database are that variations in time prior to
1970 are pointless and so should not even be recorded! Another area where
historic data is being purged, but many of the details relate specifically to
locational data which can only be accurately recorded as a map. Yes these are
also political boundaries in many cases, but it is information that needs to be
'surveyed' by access to historic material rather than simply looking on the
ground. This is an area that OHM has been set up to complete the coverage, but
in a large majority of cases, this material is still current, and so should be
in OSM first ...
The major problem I've pointed out several times is where a higher level tag
like 'timezone' is then attached to every element below the boundaries that it
relates to. We need to develop the boundary relations in a manor that a search
for a locations 'details' return all of the relevant higher level tags - if
requested! - and where a higher level tag is applied to several adjacent areas,
a single relation is created using the boundary of the whole area ... that is if
one does not already exist. I've come to the conclusion that ADDING areas is
where a lot of this is now breaking down when one needs to use the edges of
those areas for other disjointed tagging. At a lower level fields and field
boundaries where one has three ways all overlaying because two of them are parts
of areas! Moving up to residential area and other small political boundaries
which have been drawn as areas but need to be pulled apart to use existing ways
in much the same way that nodes are automatically shared?
--
Lester Caine - G8HFL
-----------------------------
Contact - http://lsces.co.uk/wiki/?page=contact
L.S.Caine Electronic Services - http://lsces.co.uk
EnquirySolve - http://enquirysolve.com/
Model Engineers Digital Workshop - http://medw.co.uk
Rainbow Digital Media - http://rainbowdigitalmedia.co.uk
_______________________________________________
talk mailing list
talk@openstreetmap.org
https://lists.openstreetmap.org/listinfo/talk
