Open IFC Tools  ( http://www.openifctools.org )   This is a set of Open Source (for non-commercial use) libraries written in Java. It should work on Windows, Linux and OSX.   They follow a modular approach, where different packages are being released in order:   Open IFC Java Toolbox 
 Boolean Modeller 
 IFC-loader for Java3D 
 4D Scheduling Assistant 
 Currently, only the Toolbox is available, together with a Java Webstart demonstration to launch the software directly from a browser. This automatically installs the necessary extensions for Java3D, OpenGL, GlueGen.  I tried the web-demo but first had to update Java3D on my Mac (as mentioned on  http://www.openifctools.org/Open_IFC_Tools/mac_java3d.html ).   This viewer loaded the ArchiCAD file without problems and displayed it adequately. You get a view on the actual IFC code, a 3D visualization, the hierarchic object tree of the Spatial structure and the particular attributes of selected entities, which is exactly what you need fr...
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