Frederic Bouvier writes:

 > I've just downloaded e000n40.tar.gz scenery file from William's site
 > to discover that lakes are missing there too. The bigger ones that 
 > appears in Curt's scenery (like the Lake of Geneva) are now flagged 
 > as Default (green) and not Lake (blue).

That could be the result of any of several problems.  Lake Geneva is
almost certainly in vmap, but perhaps there was a triangulation
problem, or perhaps e000n40 was one of William's early efforts, before
he nailed down the water stuff.  If you remind me, I can try
generating it next week and see what I get here.

 > Otherwise, I never saw such a detailed scenery for my home town in
 > whatever sim. Thanks to William, David and vmap0.

I'm glad it helped.

 > 
 > I have two remarks :
 > 1. rivers are all the of same width,

Yes.  Unfortunately, vmap0 models smaller rivers and streams as lines,
so we don't know how wide to make them.  In the future, we might make
the shorelines irregular, at the cost of more polygons

 > 2. the data set is somewhat misplaced by a fraction of kilometer :
 >    I discovered this with fgsd ( screenshot here :
 >    http://perso.wanadoo.fr/frbouvi/flightsim/fgsd-vmap0-ann.png )
 >    I presume the map is placed correctly because airports match 
 >    perfectly. You can see that the shape of the river match but is
 >    offset by a small amount. There is also a lake that does not appear.
 >    perhaps it is not in the dataset !
 >    It result in rivers climbing mountains or railroads crossing 
 >    airfields.

Yes, that does happen.  Both the DEM and vmap0 data are fairly low
resolution, so problems like this will happen.  For the Great Lake
shorelines, the error in vmap0 is only 10 or 20 metres, vs. >1000m for
the GSHHS, but the errors are still there.

As Norm has pointed out, the solution will be to load everything into
a GIS database and then tweak the data manually where necessary (and
run some automated tweaks as well).  Unfortunately, we're not set up
for that yet.


All the best,


David

-- 
David Megginson, [EMAIL PROTECTED], http://www.megginson.com/

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