[Imports] [Cat2Osm2] Tool for exporting Spanish Cadastre data in OSM suitable format

[Paul Norman]

> From: Cruz Enrique Borges [mailto:cruz.borges at deusto.es]
> Subject: [Imports] [Cat2Osm2] Tool for exporting Spanish Cadastre data
> in OSM suitable format
> 
> It also exports the result divided in urban/rural blocks which makes it
> very easy for users to validate everything is ok, remove unnecessary
> geometries and merge it with existing data. We also export in separate
> files linear or points elements that can be also interesting to import.
> 
> Here's a link with the result for a village called AldeasecaDeAlba in
> Spain [3]. If you look for Aldeaseca de Alba in OSM [4] you will see it
> almost has no data (only street without names). Cat2Osm2 exports the
> files separately as we previously said but it also concatenates them
> into a global big file just in case someone wants to use the result for
> his own GIS or for a quick review of the result. You will find all this
> files in previous link. 

I've had a partial look at the resulting .osm file and have some comments

Technical:

There appear to be some ways with duplicated way nodes (i.e. a way having
the same node multiple times, other than when closing a loop). JOSM's
validator can find these. 

There are some duplicate nodes. An example can be found at 40.8253351,
-5.4437406. I'll be talking more about duplicate nodes later.

The road network does not appear to be consistently connected, for example
at 40.8182542, -5.4476705

Tagging:

You appear to be using landuse=reservoir for unknown water. Most of the ones
I looked at would be better suited as natural=water. natural=water is also
better suited for unknown bodies of water.

Are there any tags that will be used other than those in this sample file?

The import is proposing a new tag, use=agricultural. This is found on
landuse=meadow areas. Are there any new tags that this import is proposing
to use?

How were the tag translations arrived at? Taking the example of
landuse=greenfield, was this decided on based on descriptions from the
catastro, or was it based on inspection of the areas that it applies to with
aerial imagery, surveys or other resources?

The areas tagged with landuser=greenfield aren't areas with no past or
present buildings scheduled for development (i.e. virgin ground that will be
turned into a construction site)

> Please note that the concatenated files is only
> intended for debug actions and the actual import process will be made
> with the split files inside the directories.

If you go for this method, how do you intend to handle duplicate nodes? The
problem is that if two files that contain nodes at the same position are
uploaded in two different edit sessions JOSM will not merge the nodes, even
if they were merged in the concatenated file.

Other:

To what extent do you intend the importers verify the data? Do you expect
them to 

1. Verify each object in some way against some other source (e.g. imagery)

2. Verify the file for consistency (e.g. that no buildings are in water)

3. Rely on cat2osm2's verification