After a couple of month I'd like to restart this former discussion about compatibility between "ABD objects" organized in family / part structure and Item Types as standard CONNECT Edition way how to attach custom data to elements.
The problem is that Item Types are ignored when objects are exported to IFC, regadless the object is generic MicroStation geometry, MicroStation geometry converted to ABD part or an object created by ABD tools. In GUI it looks like this:
... walls are correctly exported to IFC, but all Item Types (named Extra data in this case) are cut off and lost.
I agree with NigelPDavies (a quote from the original discussion):
Items are seemingly now the primary form of adding properties to MicroStation-speciifc applications and not being able to get that information over to a platform neutral ISO-standard file format (ie IFC) is becoming a crucial issue.
Often not everything is created in ABD, project participants can use MicroStation only to create specific parts of model, or the data can be shared from other solutions (e.g. Revit) using i-model. In such situation all EC data (Item Types) are lost, which is quite big problem. E.g. here in Czech Republic, based on government decisions from last year, all public building contract over some amount/size is required to be created in accordance to BIM from 2022. Because of this change with all building industry impact solution providers are closely cooperating with engineering and construction companies to be prepared (as far as I know Bentley has ignored it, I don't know about any such local Bentley activity).
When I talked with people from BIM SIG and BIM group, who try to be independent from one particular solution, they are quite pesimistic about using ABD to produce IFC and to use ItemTypes in any BIM worklow where IFC is a final format, because combination of products cannot ensure data will be maintained and not lost.
My questions are:
To answer your first question - no, EC data is not supported using AECOsim's IFC Export. Only DataGroup schema is mapped and converted to IFC Entity Types, with Family+Part as a secondary option (legacy: it was the original method). FWIW, I think ProStructures (which uses EC schema) might include IFC Export, though I don't know to what extent.
thanks for your answer and the confirmation of the current state.
Steve Cocchi said:To answer your first question
And what about the second part of my question? Is it planned to support Item Types (EC data in general) in IFC export? This is a nasty gap between what platform (MicroStation) team recommends to use (and many users have started use) and what is supported by AECOsim BD.
Not that I'm aware of, but I cannot say for sure. Hopefully Tathagata is able to track down additional details for that aspect.