[OSM-dev] Get geometries out of OSM changes file

[Roland Olbricht]

Hi François,

I would like to thank Simon for the more concise summary of the options.

> Do we agree about nodes lat/lon presence in an osc file as shown in the
> first example here?
> https://wiki.openstreetmap.org/wiki/OsmChange

Ahem, yes and no.

A changed way often refers to some unchanged nodes, and the geometry of
these nodes is not included in the osc file.

Also, the unchanged ways that to refer to changed nodes are not in the
osc file. This happens quite often, although the geometry changes for
these ways are usually minuscule.

A similar problem affects relations.

The caveat mentioned before is more subtle, and given mmd's statistics,
is effectively irrelevant if you can afford to be five minutes or more
behind live tracking.

Have I understood it correctly that the ultimate task is to compute per
day and per each of the 40k municipalities the number of changes and of
resulting matching objects, over a timespan of some years?

All the best,

Roland