Vladimir, Tobias, Andreas, Matthias1 and myself took part at the FOSSGIS conference at Dessau (Ger). We gave a central 3D talk for one hour and here is a short summary on the feedback:
-somebody mentioned a already developed 3D modeller for parametrized Building (was the organizer, right?)
-some requested CityGML support, that seems to be quit popular at federal institutions
-no real hard words against 3D with OSM tags (at least suprising to me)
Basically that’s it. Wasn’t that much discussion but afterwards we had some nice contacts:
-camp2camp have a WebGL globe with COLLADA buildings on top
-MARBLE devs planning to add a similar feature in late autumn
I was also quite surprised about the all in all positive feedback about 3D in OSM. I am glad that the audience apparently liked the idea
and many are interested in this development and even waiting for progress in it in order to do more 3D mapping.
Yes, that was Lothar Koppers of the HS Anhalt in Dessau. (http://www.afg.hs-anhalt.de/facility-management/personen/professoren/lothar-koppers/)
I talked to him later on. He has dealed with some aspects of crowdsourced building modelling since his PhD and recently did a project with students
about modelling school sites. In this context they apparently had some kind of “easy-to-use” 3D building modelling tool, which could be also very helpful
for OSM. I stay in contact with him and request further information soon.
One additional discussion point that occurs to me just now was:
legal/copyright issues for external repositories, under which license should 3D models in such a repository be published?
OpenWebGlobe is an excellent project. However, they also have great DEM data from Swisstopo as a basis, which makes the appearance really detailed.
AFAIK, it has been developed by the group of Stephan Nebiker at the University of Applied Science Northwestern Switzerland (http://www.fhnw.ch/personen/stephan-nebiker)
sounds quite interesting, also the camp2camp stuff. CityGML is a format that should be covered both as delivery and as input format, I think. As for using existing CityGML files in a 3D View, we’re working on a converter to XML3D and also have tried to integrate it with OSM data, see: http://wiki.openstreetmap.org/wiki/File:Citygml_osm.JPG – the two different datasets don’t align perfectly but also not that bad either Citygml model is taken from the citygml.org test data sets.
As for the copyright issues: what about CreativeCommons?
I agree that using a Creative Commons license is the way to go, but which Creative Commons license? There are three free CC licenses, CC0, CC BY, and CC BY-SA. As a data consumer, I’d of course prefer CC0 - but I expect that not all contributors will like that extremely generous license. So I’ve been thinking about the issue for a while, and I think that some aspects should be taken into account when choosing a licensing policy for a model repository:
If you use any license with a “BY” component, the repository will face one of the practical problems also encountered by OSM: Individual attribution is not always feasible. Building models in a given scene can come from many different contributors, and listing all of them in a copyright notice will become cumbersome. So if any such license is used, we should set up contributor terms for the building repository that allow collective attribution: The repository itself lists the user name of the uploader, but people using the models only need to attribute NameOfTheBuildingRepository. This would be exactly what OSM is doing now, and it seems to work for us.
However, there is another crucial requirement for the building repository: It needs to be compatible with the license of OSM data. And with the final steps of the license change process starting within a few hours, content licensed CC BY-SA is no longer fully compatible with OSM data. How much this matters depends on several legal interpretations, e.g. whether an OBJ/Collada/CityGML … file with a 3D model of an area, produced from OSM data, is considered a “produced work” or a “derivative database”. But in any case, I’d recommend avoiding any Share Alike licenses that are not the ODbL for this very reason.
So, my suggestion would be to give uploaders a choice between
CC BY, with collective attribution.
If you do want to offer a share alike option, you could add
CC BY-SA + ODbL dual licensing, with collective attribution