[OSM-talk] OSM rewriting history : France is now part of Germany !

[Lennard]

John Smith wrote:

>> It's not a node, so my guess is that label is coming from a huge
>> polygon but, stilll, I don't know what can be a polygon named
>> "Germany" and its centre is so far in the west...

There is an issue that causes labels to (far) outside the polygons, and 
that is a multipolygon with multiple outer rings. A fix has been applied 
to osm2pgsql recently, supposedly fixing this, but until the planet has 
been fully reloaded, lots of old-style objects will still be in the 
database. Still, this issue always caused the labels to outside and to 
the _east_ of the objects, and this is to the west. This particular case 
may have another cause.

> Does anyone know of a good reason for the names of polygons to render?

It makes all kinds of otherwise unhandled polygons* show up with a 
label. This includes houses, forests, marinas, quarries, etc. You name 
it: if it's a closed area with a name label, it renders. Mind you, I'm 
very much against doing this in the mapnik stylesheet, because it 
actually takes control away from us. You cannot suppress a label for 
things which really shouldn't render. The same holds true for the 
default way to render labels for every way with a name key.

I do understand, however, that requiring explicit handling to label a 
large swath of polygonic* features would require an extensive section in 
the mapnik stylesheet, and some effort to compile and decide which to 
render. Which is why it hasn't been done yet, although with the current 
modularized approach, at least it won't be a total maintenance nightmare 
anymore.

Perhaps now is the time to get around to actually fixing this, accepting 
that some labels you've come to expect to be rendered will suddenly be 
absent? Until someone notices, creates an enhancement ticket, and we 
create an explicit rule, of course.

* The same applies for ways, causing untold floating names to appear 
where there is no supporting rendered feature.

> Most of the time, there is a place node for where things should

Most of the time, there really isn't.

> render, otherwise you get the names of postcodes and names rendering
> in the middle of no where.

Indeed, which is currently the case.


-- 
Lennard