[Talk-ca] Own experience with Geobase

[Michel Gilbert]

Hi all,

I am very glad to read Richard's announcement. I experimented the conversion
of the NRN (Road Network) to Open Street Map in September and October. Here
some starting observations:

- Keep the original OSM data.I did not use Geobase data when OSM exist. In
general the matching to identify common geometries is good. However, some
manual edition is required when the representation is different in Geobase
and OSM (motorway as 1 or 2 separate ways for example).

- The OSM ways must be altered (insert nodes) to assure connectivity between
the existing OSM ways and new ways that came from Geobase segments.

- New ways that came from Geobase are tagged as followed:
<way id="-9767" action="modify" visible="true" user="pythagore">

    <nd ref="-4871"/>

    <nd ref="-4870"/>

    <nd ref="-4869"/>

    <nd ref="-4868"/>

    <nd ref="-604"/>

    <tag k="created_by" v="JOSM"/>

    <tag k="highway" v="primary"/>

    <tag k="nat_ref" v="7a8ee7aeb196462088c1fad7b7e83842"/>

    <tag k="source" v="geobase"/>

    <tag k="lanes" v="2"/>

    <tag k="ref" v="132"/>

    <tag k="name" v="Rue St-Joseph"

  </way>

·         The key value for highway came from the Geobase attribute
ROADCLASS.

·         The key value for source is set to 'geobase' to keep the origin of
the data (license issue)

·         The key value for nat_ref is the Geobase NID attribute. I kept
this ID to link the geobase Road segments at OSM ways. It will be easier, in
the future, to obtain the road/street names when they will be available.

·         The key value for lanes is the Geobase attribute NBRLANES.

·         The key value for ref is the Geobase attributes RTNUMBER1 …
RTNUMBER5

·         The key value for name is the Geobase attribute R_STNAME_C
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