How to create IfcBuiltSystem and aggregate IfcElementAssembly?

walpa

Hi,
I'm trying to organize a project and I think IfcBuiltSystem and IfcElementAssembly are good alternatives for my use case.
Here shows how to create an IfcElementAssembly. Thanks to whoever made this work! :)
Is there something similar to teach how to create an IfcBuiltSystem and aggregate an IfcElementAssembly in it?
Or can someone show me the "step-by-step"?

Thanks

theoryshaw

This help?
https://www.dropbox.com/scl/fi/xe8fqbxes4mkf39ircg40/2023-08-06_18-36-53_KeyShowView_Carnac.mp4?rlkey=w500xj5ix23inosvv9e9tsrt8&dl=0

...
curious to hear what your use case is?

walpa

@theoryshaw said:
This help?

Yes it helped a lot! But I think I missed something because I couldn't assign elements (0:37s in video).

My doubts:

1 - in the video I didn't see if a collection is created for IfcBuildingSystem (my goal of organizing the project)
2 - as IfcBuildingSystem is going to be discontinued, I thought of using IfcBuiltSystem
3 - I tried IfcBuiltSystem in the popup and the system is created (message " 1 system found" appears) and saved in the IFC file, but it does not appear for editing and neither in the outliner. I don't know if it's a bug or I'm doing something wrong. :(

Taking a closer look at the IfcElementAssembly tutorial I realized that it is still not possible to insert IfcElementAssembblyType using BIMTool. I tried 2 methods:
A - Click on BIMMTool/Create element/Add. The type assembly is created, but with the "programmed" shape

1 => expected shape
2 => element created

B - via script (like BIMTool), but I was unsuccessful because the class is not recognized (info panel)

The manual method, as proposed in the tutorial, in my use case may be unfeasible because there are 20 types of assemblies with many different elements and that originate more than 700 assemblies.

@theoryshaw said:
curious to hear what your use case is?

My use case is presented in this post.

Cheers

theoryshaw

1 - in the video I didn't see if a collection is created for IfcBuildingSystem (my goal of organizing the project)

IfcSystems do not show up in the outliner. So if your goal is to use the outlier to organize, I would either use an IfcElementAssembly or IfcSpatialStructureElement.

2 - as IfcBuildingSystem is going to be discontinued, I thought of using IfcBuiltSystem

Yes, i'm not sure why IfcBuiltSystem doesn't show up in the following pulldown.

3 - I tried IfcBuiltSystem in the popup and the system is created (message " 1 system found" appears) and saved in the IFC file, but it does not appear for editing and neither in the outliner. I don't know if it's a bug or I'm doing something wrong. :(

I'm not sure what you meant here.

Taking a closer look at the IfcElementAssembly tutorial I realized that it is still not possible to insert IfcElementAssembblyType using BIMTool. I tried 2 methods:
A - Click on BIMMTool/Create element/Add. The type assembly is created, but with the "programmed" shape

As far as I know IfcElementAssemblyType only works with (1) geometry. That is, you can't assembly/aggregate an intelligent wall and intelligent column together and then have 100 instances of that.
As I understand it, however, I 'think' it should work this way. It just hasn't been implemented yet.
...
Thankfully, however, @bruno_perdigao, the following pull request, has added some alpha functionality that allows for 'Aggregate/Assembly Types'--such that if the parent changes, all the instances change.
https://github.com/IfcOpenShell/IfcOpenShell/pull/3328

walpa

@theoryshaw said:
IfcSystems do not show up in the outliner. So if your goal is to use the outlier to organize, I would either use an IfcElementAssembly or IfcSpatialStructureElement.

Thank you, I will change my strategy and follow your advice.

Yes, i'm not sure why IfcBuiltSystem doesn't show up in the following pulldown.

Reported bug!

As far as I know IfcElementAssemblyType only works with (1) geometry. That is, you can't assembly/aggregate an intelligent wall and intelligent column together and then have 100 instances of that.
As I understand it, however, I 'think' it should work this way. It just hasn't been implemented yet.

Ok, I understand how IfcElementAssembly and IfcElementAssemblyType work

Thankfully, however, @bruno_perdigao, the following pull request, has added some alpha functionality that allows for 'Aggregate/Assembly Types'--such that if the parent changes, all the instances change.

Here I have my problems, from what I've seen in other posts, the shortcut ctrl+shft+d is used to copy the instance, but in my use case I think I need to create IfcElementAssembly instances from IfcElementAssemblyType via script.
I'll leave a comment in this thread, maybe I'll get some help.

Thanks

theoryshaw

seems like 'IfcBuiltSystem' is only in IFC4x3....
https://github.com/IfcOpenShell/IfcOpenShell/assets/507113/fb592599-3c60-416b-a33e-e9beb4ff0a77

walpa

@theoryshaw said:
seems like 'IfcBuiltSystem' is only in IFC4x3....

Yes I know. Thanks