BB crashes with this file

T by theoryshaw on 28 Oct 2022, edited 29 Oct 2022 #

The following file crashes BB, quite frequently, when import.

https://www.dropbox.com/s/z49gzbiulxvtbqp/101_W_33rd_St_Structure.ifc?dl=1

Blender 3.2

Can anyone test?

C by Coen on 28 Oct 2022 # +2 votes

Seems to work for me

On Blender 3.3.0 with BlenderBIM add-on 0.0.221027, Windows 10.

M by Moult on 29 Oct 2022, edited 29 Oct 2022 #

Loads instantly for me, no crash. Blender 3.3.

What happens if you comment out this line? https://github.com/IfcOpenShell/IfcOpenShell/blob/v0.7.0/src/blenderbim/blenderbim/bim/module/project/operator.py#L595

T by theoryshaw on 29 Oct 2022 #

@Moult said:

Loads instantly for me, no crash. Blender 3.3.

What happens if you comment out this line? https://github.com/IfcOpenShell/IfcOpenShell/blob/v0.7.0/src/blenderbim/blenderbim/bim/module/project/operator.py#L595

That was it, no more crashy. :)

T by theoryshaw on 29 Oct 2022 #

Spoke too soon. It opens now, no problem, but when i try to instantiate a type and change its length, it crashes.

M by Moult on 29 Oct 2022, edited 29 Oct 2022 # +1 votes

I think that's because Revit is wrong, here is the note from the IFC4 docs on IfcBeamType:

NOTE If the IfcBeamType has an associated IfcMaterialProfileSet, then no shared geometric representation shall be provided.

Whereas Revit supplies both an IfcMaterialProfileSet and geometric representations. This trips up our system which expect there to be either 1) a shared representation or 2) a parametric material set which are mutually exclusive.

If you click on the IfcBeamType, go into IFC Representations and remove the two representations, then add a beam, it should start to behave normally.

Edit: filed a bug for Autodesk: https://github.com/Autodesk/revit-ifc/issues/536

M by Moult on 29 Oct 2022, edited 29 Oct 2022 # +1 votes

Another super crazy thing Revit is doing is for another beam and that it's actually treated it as a composite profile with 14 subprofiles. I've got no idea what internal logic Revit is doing to decide that this should be the case. It's also invalid because Revit doesn't create the composite profile, so you won't be able to edit that beam either. Here's the relevant snippet from the IfcMaterialProfileSet docs:

Reference to the composite profile definition for which this material profile set associates material to each of its individual profiles. If only a single material profile is used (the most typical case) then no CompositeProfile is asserted.

NOTE The referenced IfcCompositeProfileDef instance shall be composed of all of the IfcProfileDef instances which are used via the MaterialProfiles list in the current IfcMaterialProfileSet.

Edit: reported as well to Autodesk https://github.com/Autodesk/revit-ifc/issues/537

T by theoryshaw on 29 Oct 2022 # +4 votes

Can we add a cry emoji to the forum? ;)