Closed araccaine closed 1 week ago
You're correct with the "RelatedIfcEntityNamesList": [ "IfcBeamLINTEL" ]
example. You can't use USERDEFINED because that is not a defined class in IFC dictionary. I know there is a dichotomy between official IFC4.3 and what we published in bSDD.
That is because we are trying to educate people not to use USERDEFINED and NOTDEFINED options, and instead simply leave the predefined type empty and assign a class (IfcClassificationReference) to a registered term. This way we increase consistency of the information.
To answer to your use case, I recommend modeling this as an IfcBeam without predefined type, with an IfcClassificationReference to MyBeam
from your dictionary. And yes, MyBeam
can be registered with relation IsChildOf
IfcBeam. The added value of this approach is that one element can have multiple class references (for example if you are using multiple systems), which was not possible with predefined types.
As I understand the documentation, the field
RelatedIfcEntityNamesList
can have multiple related IFC entitites."RelatedIfcEntityNamesList": [ "IfcBeam" ]
IfcBeam
with predefined typeLINTEL
would be e.g."RelatedIfcEntityNamesList": [ "IfcBeamLINTEL" ]
But how do we define a
IfcBeam
with the USERDEFINED typeMyBeam
? Do we need to define a new relation withIsChildOf
or something like that?