> Date: Sat, 31 Dec 2011 14:55:08 +0100
> From: wmgcnfg@web.de
> To: mkgmap-dev@lists.mkgmap.org.uk
> Subject: Re: [mkgmap-dev] [PATCH v1] LocationHook speedup
>
> Am 31.12.2011 14:51, schrieb Gerd Petermann:
> > Hello WanMil,
> >
> > > admin_level=7 just an example. admin_levels are used differently in
> > > countries and in regions etc.
> > >
> > > > I see
> > > > "Verbandsgemeinde Waldmohr"
> > > > http://www.openstreetmap.org/browse/relation/897709
> > > > which is the only boundary that has admin_level=7. The interesting
> > thing is:
> > > > the returned result-list for this boundary is always empty. So,
> > maybe there
> > > > is a cheaper way to detect this first or does it means that there
> > is a bug
> > > > in quadtree or the selection of the boundaries?
> > >
> > > Sounds more like a bug! But it's also possible that the higher
> > > admin_levels (8,9,10,11) references all other admin_levels and therefore
> > > there all elements of Waldmohr have been removed before querying for it.
> >
> > hmm, I think you missed the point that we start with lower admin_levels:
> > // Reverse the sorting because we want to start with the lowest admin level
> > Collections.reverse(boundaries);
>
> No, I didn't. I should have better written admin_levels (11,10,9,8) but
> the meaning is the same.
No, not really. We check 2,4,5,6 first.

>
> >
> > and I found Waldmohr because it prevented the elements from being "fully
> > worked out".
>
> Sounds reasonable. But then querying for Waldmohr should have returned
> some elements, shouldn't it?
No, all elements are kept in the quadtree because they are not "fully worked out" until this admin_level=7 part is done, or to be more precise, until they are processed for admin_level=8 or higher, because for admin_level=7 nothing is changed in this special case.

Gerd