> > The larger part of cadastre data > is just dumped into the data base never to be touched again by any mapper.
That's also wrong, the french community has developed some very powerful tools like osmose.openstreetmap.fr which is used to automatically discover many errors from cadastre and others, it's used along the import process by many people to locate and fix many bugs, for example here is a search focused on some errors that we seek : http://osmose.openstreetmap.fr/map/?zoom=12&lat=45.22034&lon=5.74928&layers=B00FF0FFFFFFFFFFFFFFFFFFT&item=0,1040,3091&level=1 Osmose is going worldwide for some analysis, so other community will benefit from this great tool. There are also many go and return between data from cadastre and already in place data like roads and POI, the locations of each objects is used to improve the global accuracy (also with the help of other source : Bing,...). I discovered and fixed many roads and POI with the help of the building footprints, in the process I try also to fix errors on cadastre that I can spot, some split buildings from time to time,... Very often I can spot isolated buildings imported from cadastre and make search how to map the missing roads. There are also IGN (french geomatic institute) landmarks which have been imported in the base, they are very accurately positioned reference physical points like the cross of church,... They are often used to precisely fix the location of the cadastre data if needed. > > no addresses or names or pois. It is rather ugly for rendering, there are > no real buildings just unspecific building parts and way too much detail > (small round edifices using up 40 nodes, what for?). You cannot do real > statistics on them, there are just unspecific building parts... > So essentially alomost every data user has to go through 25 million > buildings just to throw them away. It is not the end of the world, > but it is mildly annoying. I don't agree the cadastre is ugly once rendered ! A rendered map like this for example, is in my opinion something more pleasant than a map with only a house once and there with large holes : http://www.openstreetmap.org/?lat=43.70272&lon=7.26654&zoom=15&layers=Q This data is also beautifully used by the community behind 3D rendered map used in X-Plane flight simulator. 3D maps is something on the rise and detailed buildings are needed for this ! Regards, Vlad. _______________________________________________ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk
