[OSM-dev] thematic editing

[Frederik Ramm]

Hi,

Mikel Maron wrote:
> I'd like to investigate getting this end result in JOSM, without the 
> manual steps below
> * Define the thematic layers in perferences (HEALTH is amenity=hospital, 
> amenity=pharmacy, ROADS is highway=*, etc)
> * Add a panel which toggles visibility on each of those thematic layers. 
> By default, there would be a layer for everything else not caught by the 
> defined themes
> * ok, that's what I really want!

In fact, JOSM has a hidden and even-less-than-usual documented feature 
that does much of this. It is called "display filter" and you need to 
manually set the config option

displayfilter=true

to use it. What it essentially does is that it allows you to save any 
search (e.g. amenity=hospital,amentiy=pharmacy) into a named filter and 
then apply that filter to your data at any time. For each filter you can 
say whether objects matching (or not matching) the filter should be 
visible and/or editable. You can even stack filters on top of each other.

However, the whole thing is a user interface nightmare. There are all 
sorts of things that can happen, for example what if someone has 
connected a pharmacy node to a footway and you switch your health filter 
on - then if you move the pharmacy you don't see that you are moving a 
footway too. Or what if you have the health filter on and accidentally 
tag your pharmacy as bakery - it will simply vanish and you will never 
know that it is still there "behind the scenes". And so on. This can all 
be solved probably but it will need a lot of testing.

I believe someone is working on improving the UI at the moment. But it 
seems unlikely to me that this is ever going to be a newbie friendly 
feature...

Bye
Frederik

-- 
Frederik Ramm  ##  eMail frederik at remote.org  ##  N49°00'09" E008°23'33"