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BIMserver.org on FOSS4G2009

These days all the open source GIS nerds are attending the FOSS4G (Free and Open Source Software for Geospatial information) congress in Sydney Australia. Because the BIM world and the GIS world are starting to overlap each other, BIMserver.org was also present at this conference. We made a contribution by presenting the CityGML extension for BIM and it’s implementation in BIMserver.org. For those of you who missed it you can find the sheets, the extension and some example files on foss4g.BIMserver.org.

Update: find everything on http://archive.opensourcebim.org/BIMserver/foss4g/

 

Linking BIM and GIS

The world of BIM is getting more and more about buildings in a surrounding instead of just one building. The world of GIS is getting more and more about 3D objects and making the breach above the surface. These two worlds are getting closer to each other. The first part where these two worlds meet is CityGML. CityGML is an initiative to store semantic information about cities. The information is about buildings, but also surrounding (roads, etc) and geographic information is stored in the same standard.
The information about buildings in CityGML is very basic. Because at a city-level only the envelope of a building is interesting, there is no possibility to store information about floors, innerwalls, and other information about the inside of a building.
Luckily however CityGML gives developers the possibility to extent the standard with a specific Application Domain Extension (ADE).  BIMserver.org is developing a ADE for BIM information in CityGML. This development isn’t done in a day. We are working on it for quit some time now and it won’t be done overnight. Most important part is the transformation of the geometry. We are using the IFCEngine DLL from TNO to transform the semantic geometry of IFC to explicit geometry of GML.
The first results of this transformation are captured in a screenshot which we don’t want to keep for ourselves.
What you see is an IFC model in the free IFCbrowser (top) and the same model, transformed by the BIMserver software to CityGML in the FZKviewer.
Remember: still a long way to go….
The world of BIM is getting more and more about buildings in a surrounding instead of just one building. The world of GIS is getting more and more about 3D objects and making the breach above the surface. These two worlds are getting closer to each other. The first part where these two worlds meet is CityGML. CityGML is an initiative to store semantic information about cities. The information is about buildings, but also surrounding (roads, etc) and geographic information is stored in the same standard.

The information about buildings in CityGML is very basic. Because at a city-level only the envelope of a building is interesting, there is no possibility to store information about floors, innerwalls, and other information about the inside of a building.

Luckily however CityGML gives developers the possibility to extent the standard with a specific Application Domain Extension (ADE).  BIMserver.org is developing a ADE for BIM information in CityGML. This development isn’t done in a day. We are working on it for quit some time now and it won’t be done overnight. Most important part is the transformation of the geometry. We are using the IFCEngine DLL from TNO to transform the semantic geometry of IFC to explicit geometry of GML.

The first results of this transformation are captured in a screenshot which we don’t want to keep for ourselves.

What you see is an IFC model in the free IFCbrowser (top) and the same model, transformed by the BIMserver software to CityGML in the FZKviewer.

Remember: still a long way to go….!