[OSM-talk] AND China data

[D Tucny]

Hi Kleptog,

There was some useful data in the AND dataset for China, so, I'm hoping we
can push forward and get some of it used... As you did most of the work on
processing the India and China data, I'm coming back to you for help :)

My thoughts back in December are below... Place information has been
imported from GNS now... Would it be possible to get just province
boundaries, with names and water extracted? Perhaps into separate files as
the water will at least need to be blended in with PGS around the coastal
areas and the province boundaries had the issue with borders around 1000s of
islands, plus it would be good to add in the Chinese for at least the
province place tags, all of which would be good to clear up prior to an
import...

Thanks,

d

--- snip ---
So, in summary, the data we have is (with my opinions on it below)...

Places, cities plus some towns and villages where they are in the road
network.
 - Possibly worthwhile importing, but probably best to merge in the GNS
data, or, only use the GNS data... The fact that the places are nodes in the
road network is probably an issue too...

Place areas, the borders around an the urban area.
 - Looks nice, but, probably never very accurate and now, it is very out of
date... Realistically, probably not worth importing...

Airports
 - Probably not worth importing, the locations of the ones I've checked are
not overly accurate, some are way out, (10+km) and we already have airport
data. There are 'service roads' connecting the nearest road to the airport
in a straight line, these are definitely not worth importing I would say...

Water
 - Worthwhile importing, but, needs some more fixing up, and will need some
careful merging with existing, better PGS data near the coast at least...

Coastline
 - Not worth importing, the PGS data seems more recent, higher resolution
and a lot has already been imported and has had a lot of time spent on
tidying up...

Administrative Boundaries
 - Definitely worthwhile importing, will need some tidy up along the coasts,
especially where there are islands, and adding more tagging data, like the
name in Chinese would be useful... This would probably be a bit of data that
would benefit from being lockable...

Roads
 - I'm still not convinced by these... The fact that they seem obviously
very out of date, have a low resolution, lack names or references and the
fact that they in many cases just seem to join together in a city point
makes me think that they don't really add much... Obviously they would make
it look like we had data, but, I don't think, they really give us anything
approaching usable data... As it stands, I'd say they are not worth
importing... Potentially splitting the road data out and breaking it down
based on provinces and leaving those files somewhere accessible would be
useful, maybe at some point the the future, someone in a remote location may
find that the data is useful for their area, but, even if an area hasn't had
any road improvements in the past 10-20 years, pretty unlikely for major
roads even in remote locations, I'm not convinced the data would even give
much value there... As I mentioned in IRC, our data would probably be a more
accurate reflection of what's there if we imported all the GNS places, and
joined all large cities together with straight lines tagged as motorway,
drop a bit of terrain information into the process to make some curves and
it would probably be a lot more accurate, could then even join up smaller
cities with non-motorways... I'm not suggesting we do this, I'm just trying
to explain my feel on the data that if all we want is less white space,
making data up using some form of guestimation as to where roads would
probably be built would probably give us something more useful/accurate than
this road data...
--- snip ---
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