Hello Wall - IfcWallElementedCase

J by Johannes990 on 23 Oct 2022, edited 21 Apr 2023 #

Hi All,

I am new in blenderBIM and I am trying to create a wall using the IfcWallElementedCase specifically, I would like to create an internal wall stud. And I have some queries/biases that I would like to ask you.

As I understood, the IfcWallElementedCase is made up by:

IfcRelDefinesByType -> obj relation of the type in this case IfcWallType in this case ( is this a mandatory requirement? correct? )

IfcRelAggregates -> obj that defines the relation of the subcomponent of the wall like the panels, the insulation studs etc.

IfcRelAssociatesMaterial -> Am I correct to think that this element defines the association within the array's subcomponent of the wall and retrieve its material (https://standards.buildingsmart.org/IFC/DEV/IFC4_3/RC1/HTML/link/ifcrelconnectswithrealizingelements.htm) "" The IfcRelAssociatesMaterial relationship is a special type of the IfcRelAssociates relationship. It can be applied to subtypes of IfcElement and subtypes of IfcElementType.

The IfcElement has an inverse relation to its material definition by the HasAssociations attribute, inherited from IfcObject.

The IfcElementType has an inverse relation to its material definition by the HasAssociations attribute, inherited from IfcPropertyDefinition.

"

InBlender BIM the IfcRelAggregates is this ? also, I have the feeling that in the dropdown trees there is quite messy

Thank you in advance,

Gian Claudio :)

C by Coen on 25 Oct 2022 #

I would also like to how to create an IfcWallElementedCase

C by cvillagrasa on 25 Oct 2022 # +3 votes

IfcWallElementedCase seems to be deprecated from IFC4 onwards, and afaik BlenderBIM is not superfocused on IFC2x3.

On a side note regarding bSI website, I find when something's deprecated, there could be a brief statement as of why, and what is the alternative in the modern version of the schema.

J by Johannes990 on 26 Oct 2022 #

Thank you all,

I have been trying and failing. However, I am starting to understand the logic of the "IfcRel..."

I found insightful those videos...

and when I am digging in the GitHub repo, there are a lot of features on the ifcopenshell (some still #TODO) . This is definitely a game-changer for the ACEO Might really good as well for the OPEX level... , hopefully, I can be a bit better at my coding skill to support this!

I will keep you posted when I find a solution :)

C by Coen on 15 Apr 2023 #

I will keep you posted when I find a solution :)

Did you already found a solution? I would like to IfcRelAggregate this together, no idea on how to do it:

T by theoryshaw on 15 Apr 2023 #

can you share the file? :)

C by Coen on 15 Apr 2023 # +2 votes

@theoryshaw said:

can you share the file? :)

Yes ofcourse, it's an autogenerated ifc by the way.

Trying to create this for myself as an blenderbim/ifcopenshell add-on exercise.

C by Coen on 15 Apr 2023 #

ChatGPT gave this as an example to create an IfcRelAggregate


rel_aggregates = ifc_file.createIfcRelAggregates('1AEAi$cjvFNxxkPAdOIzkr', global_id_list)


# set the Name attribute of the IfcRelAggregates object

rel_aggregates.Name = "Example Aggregation"


 # add the IfcRelAggregates object to the IFC file

ifc_file.add(rel_aggregates)

Is it really that simple?

T by theoryshaw on 15 Apr 2023 #

oh, sorry, you're asking how to do it programmatically. I should have known. :\

Not sure, then. :)

C by Coen on 15 Apr 2023 #

@theoryshaw said:

oh, sorry, you're asking how to do it programmatically. I should have known. :\

Not sure, then. :)

Not per se, I also would like how to know to do it with the UI :-)

T by theoryshaw on 15 Apr 2023, edited 15 Apr 2023 # +1 votes

Well in that case. :)

Collection instances, toward the end of the video, is not current possible with NativeIFC , but wouldn't 'typed aggregates' be awesome!? :)

C by Coen on 15 Apr 2023 #

oh wow thanks! that is really cool, no idea that was possible with Blender.

is not current possible with NativeIFC , but wouldn't 'typed aggregates' be awesome!? :)

YES!

I think @RaphaëlVouilloz also has experience with this creating rafters?

C by Coen on 15 Apr 2023 #

@theoryshaw said:

Well in that case. :)

Collection instances, toward the end of the video, is not current possible with NativeIFC , but wouldn't 'typed aggregates' be awesome!? :)

Can an IfcRelAggregate behave as an IfcWall? For example be cut by IfcOpeningElements?

T by theoryshaw on 15 Apr 2023 # +3 votes

Wow, I guess you can!

never knew.

T by theoryshaw on 15 Apr 2023 #


#411=IFCRELVOIDSELEMENT('3bNLdeB6f6Ex$aF98udllc',$,$,$,#323,#395);

  /*#323=IFCELEMENTASSEMBLY('292LoKrmD52eRjgEo2VhWv',$,'Assembly',$,$,#333,$,$,$,$);*/

    /*#333=IFCLOCALPLACEMENT($,#332);*/

      /*#332=IFCAXIS2PLACEMENT3D(#329,#330,#331);*/

        /*#329=IFCCARTESIANPOINT((0.,0.,0.));*/

        /*#330=IFCDIRECTION((0.,0.,1.));*/

        /*#331=IFCDIRECTION((1.,0.,0.));*/

  /*#395=IFCOPENINGELEMENT('0PR_7_fYz08Q9xGb4pLpwF',$,'Opening',$,$,#416,#410,$,$);*/

    /*#416=IFCLOCALPLACEMENT(#333,#415);*/

      /*#333=IFCLOCALPLACEMENT($,#332);*/

        /*#332=IFCAXIS2PLACEMENT3D(#329,#330,#331);*/

          /*#329=IFCCARTESIANPOINT((0.,0.,0.));*/

          /*#330=IFCDIRECTION((0.,0.,1.));*/

          /*#331=IFCDIRECTION((1.,0.,0.));*/

      /*#415=IFCAXIS2PLACEMENT3D(#412,#413,#414);*/

        /*#412=IFCCARTESIANPOINT((1980.76593875885,1339.77329730988,57.8264072537422));*/

        /*#413=IFCDIRECTION((0.,0.,1.));*/

        /*#414=IFCDIRECTION((1.,0.,0.));*/

    /*#410=IFCPRODUCTDEFINITIONSHAPE($,$,(#429));*/

      /*#429=IFCSHAPEREPRESENTATION(#11,'Body','SweptSolid',(#428));*/

        /*#11=IFCGEOMETRICREPRESENTATIONSUBCONTEXT('Body','Model',*,*,*,*,#10,$,.MODEL_VIEW.,$);*/

          /*#10=IFCGEOMETRICREPRESENTATIONCONTEXT($,'Model',3,1.E-05,#9,$);*/

            /*#9=IFCAXIS2PLACEMENT3D(#6,#7,#8);*/

              /*#6=IFCCARTESIANPOINT((0.,0.,0.));*/

              /*#7=IFCDIRECTION((0.,0.,1.));*/

              /*#8=IFCDIRECTION((1.,0.,0.));*/

        /*#428=IFCEXTRUDEDAREASOLID(#430,#426,#427,499.999970197677);*/

          /*#430=IFCARBITRARYCLOSEDPROFILEDEF(.AREA.,$,#432);*/

            /*#432=IFCINDEXEDPOLYCURVE(#431,(IFCLINEINDEX((3,2)),IFCLINEINDEX((2,1)),IFCLINEINDEX((1,4)),IFCLINEINDEX((4,3))),.F.);*/

              /*#431=IFCCARTESIANPOINTLIST2D(((-1184.55135822296,-249.999985098839),(521.828413009644,-249.999985098839),(521.828413009644,1302.30855941772),(-1184.55135822296,1302.30855941772)));*/

          /*#426=IFCAXIS2PLACEMENT3D(#423,#424,#425);*/

            /*#423=IFCCARTESIANPOINT((0.,0.,-249.999985098839));*/

            /*#424=IFCDIRECTION((0.,-0.,-1.));*/

            /*#425=IFCDIRECTION((-1.,0.,0.));*/

          /*#427=IFCDIRECTION((0.,0.,-1.));*/

T by theoryshaw on 16 Apr 2023 #

The following could be a way to create beam systems with different types of (nonrectanlinar) shapes.

Would be cool if the 'IFC Array' tool created aggregates, by which you could apply these ifcopenelement outlines.

C by Coen on 16 Apr 2023 #

@theoryshaw said:

Wow, I guess you can!

never knew.

Nice! I see it cuts through 3x IfcCovering + 1xIfcMember. This could be used for cavity walls as well. But how would one then parametrically drive the height and length of an IfcRelAggregate?

C by Coen on 16 Apr 2023 #

@theoryshaw said:

The following could be a way to create beam systems with different types of (nonrectanlinar) shapes.

Would be cool if the 'IFC Array' tool created aggregates, by which you could apply these ifcopenelement outlines.

It looks cool and useful, but I don't understand what you are doing here. I never used that tool

C by Coen on 16 Apr 2023 #

Just out of curiosity, is it possible to IfcRelAggregates two seperate IfcRelAggregates? Can't think of a usecase for this. but who knows.

C by Coen on 16 Apr 2023, edited 16 Apr 2023 #

Is it possible to add an IfcRelAggregate to an IfcProjectLibrary? How would I do that using the Blender UI?

C by Coen on 16 Apr 2023 #

Just thinking out loud, if you could have a seperate Blender session in which you could parametrically create objects, then some button which 'bakes' an IfcRelAggregates the IFC into an IfcProjectLibrary, load into your 'main' modelling Blender sessions. You could have a same workflow as Revit with families? Then how would one swap all the IfcRelAggregates when they are updated in the main model?

C by Coen on 16 Apr 2023 #

Final question ?, is possible to tranform an IfcRelAggregate? Rotate the entire object using ifcopenshell?

T by theoryshaw on 16 Apr 2023 # +1 votes

It looks cool and useful, but I don't understand what you are doing here. I never used that tool

It's just any ifcopenelement. Same approach as the original video, but with a outer profile and an inner profile.

T by theoryshaw on 16 Apr 2023 # +1 votes

@Coen said:

Just out of curiosity, is it possible to IfcRelAggregates two seperate IfcRelAggregates? Can't think of a usecase for this. but who knows.

Yes, you can do nested aggregates.

R by RaphaëlVouilloz on 17 Apr 2023 # +1 votes

@Coen said:

oh wow thanks! that is really cool, no idea that was possible with Blender.

is not current possible with NativeIFC , but wouldn't 'typed aggregates' be awesome!? :)

YES!

I think @RaphaëlVouilloz also has experience with this creating rafters?

Yes here: https://enac-cnpa.github.io/BlenderBIM-Tutoriel-Villa-Le-Sextant/5_modelisation-ifc.html#IfcRoof%20&%20IFC%20Aggregate%20(=%20Assembly)

As there is no way for the moment in the BIM Tool, I had identified these problems to make "typed aggregates" by copying a first instance:

-with an array: in Blender an empty simply does not have a Modifiers menu...

-duplicating a whole collection is not saved in the IFC by BlenderBIM

-duplicating in the scene keeps the relationship of the parts with the first assembly, so you have to manually edit all the aggregation relationships with the second assembly. This is my solution for now :)