[Talk-GB] Sorting out layering in East Anglia, Essex, London and Kent

Andy Allan gravitystorm at gmail.com
Tue Apr 19 14:50:45 BST 2011

On Tue, Apr 19, 2011 at 2:31 PM, Peter Miller <peter.miller at itoworld.com> wrote:
> Andy Allan just asked me a question privately about changes I have made to
> layers in Wandsworth which has prompted me to do a post here saying what I
> have been up in order to rationalise use of the layers in East Anglia,
> London and now Kent.
> The ITO Map 'Layers' view highlighted a huge amount of weird layer tags in
> the area. London seemed to be particularly bad. There were parks at layer-5
> and lakes at layer 1; railways at layer=1 or -1 even though they were on the
> ground.

So my concern was that data is being removed for no particularly good
reason. For example, at


the two central carriageways were tagged layer=-1 to show they are
below the nearby sliproads, but Peter has removed these layer tags.
I'm assuming his map layers view has some logic that layers tags only
apply to ways that cross but I don't believe that to be true. He's
also removed the layer tags from stretches of the railway, for example


which again, those of us who know that area know the railway is on a
different layer to the surrounding roads. While there is an argument
in both cases that there could be additional methods of tagging the
situation (such as adding embankment or cutting tags) I still don't
see that removing the layer tags is doing anything other than removing
the correct information that was there previously.


More information about the Talk-GB mailing list