[OSM-dev] Chopped of ways. Change Default or remove ID

Jochen Topf jochen at remote.org
Thu Aug 14 14:19:00 BST 2008

On Thu, Aug 14, 2008 at 02:06:13PM +0100, Nick Austin wrote:
> On Thu, Aug 14, 2008 at 9:31 AM, Jochen Topf <jochen at remote.org> wrote:
> > On Thu, Aug 14, 2008 at 09:46:45AM +0200, Marcus Wolschon wrote:
> >>
> >> I propose to not modify ways by default and to remove the way-id of
> >> ways that are modified during extraction.
> >> What should a tool care if the way references node-ids that it has
> >> no nodes for because they are outside the bounding-box? It has to ignore
> >> them.
> >>
> >> The removal of the ID is because this is no longer the way with
> >> that ID but a new and artificially created way that contains a part
> >> of the original one.
> >
> > If you remove the ID the way can't be referenced any more from
> > relations which you might also have in the OSM file. But I agree that
> > the way is somehow different, not the same anymore so it might not have
> > "a right" to this ID.
> >
> > In a more general case, if you remove some tag from a node and leave of
> > the ID because of that, you can't reference it any more from ways, which
> > might make the node useless. There are good reasons for removing, say
> > all "created_by" tags, because they take a huge amount of space and most
> > people will not need them.
> Then just flip the sign of the ID to make it a negative number, (unless negative
> IDs already have some meaning of which I'm not aware).

They have. Negative IDs are used by JOSM and other tools to denote new,
not yet uploaded objects. So this would make the problem even worse, as
it could lead to re-uploading of broken ways.

Jochen Topf  jochen at remote.org  http://www.remote.org/jochen/  +49-721-388298

More information about the dev mailing list