On Sun, Jul 22, 2012 at 01:40:48PM +0200, Stefan Keller wrote:
Hi Sarah
2012/7/22 Sarah Hoffmann lonvia@denofr.de:
New subject, as it is not really related to the initial mail.
On Sun, Jul 22, 2012 at 12:43:12PM +0200, Stefan Keller wrote:
I've taken a random sample out of the change set http://www.openstreetmap.org/browse/node/983813495/history mentioned
It was just brought to my attention that this bus stop may even not exist anymore. Anybody care to go for a walk and have a look? :)
I would recommend that (possibly) misplaced objects are never deleted, but moved if you want to enhance the location.
I agree to that in theory but in practice JOSM is really a pain when it comes to removing nodes from ways.
JOSM is not supporting this? And I thought it's the best OSM editor around... ;-> But still: as you're answer implies, it's possible though and it's even desirable. I should add this to the JOSM feature wishlist.
It it possible with the unglue function. But especially in a case like the above where the node is on the middle of an intersection, things get very messy. (And don't even get me started on relations... ;)
What remains to me is the following, since I'm having in mind OSM which is more and more related to "external databases". First, I'm still convinced that the principle of update (versus delete and recreate) should hold also for OSM. Second, we seem to have a problem with stable id's in OSM (osm_id).
Having external id's in OSM now seems to me like a necessity (in order to become related to external dbs) and a concession to the fact the OSM doesn't have stable ids. At least it's also an indication or flag to OSM users.
One of the big TODOs of OSM. Closest thing we have at the moment is Rolands proposal base on the Overpass API: http://wiki.openstreetmap.org/wiki/Overpass_API/Permanent_ID
Problem is that it is pretty hard to define what is 'stable' in the context of OSM. How should splitting of ways be handled? What if a shop moves to the next building? What if we split the bus stops into two, one for each direction? So, we actually end up with a n-to-n relation: one OSM object might have multiple UIDs (for the shop, for the building, for the address...) and a UID might reference multiple OSM objects (split ways).
Sarah