search

Autodesk / revit-ifc

IFC for Revit and Navisworks (2019+)
486 stars 196 forks source link

Virtual elements needed for IFC4 space boundaries #104

Open jmirtsch opened 5 years ago

jmirtsch commented 5 years ago

https://github.com/Autodesk/revit-ifc/blob/Dev/Source/Revit.IFC.Export/Exporter/SpatialElementExporter.cs

"RelatedBuidingElement" is mandatory in IFC4 so the exporter should generate an IfcVirtualElement when there is no physical element. https://standards.buildingsmart.org/IFC/RELEASE/IFC4/ADD2/HTML/link/ifcrelspaceboundary.htm

pipauwel commented 4 years ago

Could this item somehow be solved? Is anyone in charge of this? I could use this as well in any case (instead of having to build a separate export that includes just this).

AngelVelezSosa commented 4 years ago

We've been working on IFC4 RV so this is on the back burner. Is there an MVD that uses this?

pipauwel commented 4 years ago

I am terrible at answering MVD questions really. In any case, I tried the ReferenceView IFC4 in the exporter and ended up with lines like the below, in which the RelatedBuildingElement attribute is empty ($).

#3638= IFCRELSPACEBOUNDARY('0iJv8BPET8IvW6fRSZZTmt',#48,'2ndLevel',$,#3257,$,#3637,.VIRTUAL.,.INTERNAL.);

If it is not included because no MVD defines it, then I guess that answers the why question in any case.

AngelVelezSosa commented 4 years ago

Probably that line shouldn't be there at all in IFC4 RV. I'll check on this.

AngelVelezSosa commented 4 years ago

How did you generate your file @pipauwel ? IFCRELSPACEBOUNDARY isn't part of RV and is supposed to be factored out.

pipauwel commented 4 years ago

I notice that I am in an earlier version - 19.3.0, so that is of course the reason. My apologies. If IFCRELSPACEBOUNDARY is going to be factored out, then how will these space boundaries be included in IFC4 export?

Thanks for responding @AngelVelezSosa.

AngelVelezSosa commented 4 years ago

@pipauwel : great Q. The only "general" approved MVD for IFC4 doesn't have it. So the current answer is : they wouldn't be. There is the fake DTV MVD, which could support it, but again that's not real. So I think it's an open question for how to proceed as a community.

JOuellette-Autodesk commented 1 year ago

@AngelVelezSosa While there are UI/UX elements in the Export interface, the user can't add any of the checkbox options to an official MVD selection. But, should we make it possible with additions to the header indicating the "enhancements"?

AngelVelezSosa commented 1 year ago

You have to make a duplicate and then you can change the checkbox options. But IFC4 RV doesn't have space boundaries, and I don't think it has that as an addon option?