It's getting more and more common to exchange model data using IFC-files. In one project we are working across CAD-systems (AutoCAD Architecture, Revit Architecture and ArchiCAD). ArchiCAD and Revit handle the global unique identifiers (GUID) correctly. For example if I create a wall in Revit and export to IFC file and then import to ArchiCAD, it has the same GUID if I edit in ArchiCAD and export back to IFC. If I try to do the same with AutoCAD Architecture, the program exports a new GUID for that wall. The result is that we can't know which object is which. The identity gets lost.
My guess is that when AutoCAD Architecture imports an IFC-file, it creates new dwg-files and therefore, it also creates new GUID's during export to IFC. This is a pretty serious problem and makes it impossible to use ACA in these kind of projects. Does anyone have any experience or thoughts on this problem?
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