(WORKAROUND) incomplete ifc export. operating error?

This forum section is only for IFC-related issues
User avatar
bernd
Veteran
Posts: 12849
Joined: Sun Sep 08, 2013 8:07 pm
Location: Zürich, Switzerland
Contact:

Re: (WORKAROUND) incomplete ifc export. operating error?

Post by bernd »

it depends what you would like to archive ... Just for viewing your BIM data in a model view application eithe no solids or a mesh representation would be fine. But if someone would like to use your data for further geometric workit makes sense to provide valid good and no corrupt data. Solids or even parametric objects with extrusions would be the choice for this.

As an example I am a structural engineer. On a new project with a underground car parking we are very much interested how much earth is on the slab. For this we use the new earth surface from landscape architect and the slab surface from the architect to create a solid earth geometry. In most projects this is very cumbersome because we get very poor geometric data. Thus lots of work has to be done to create valid good geometry out of the data we get.
User avatar
thomas-neemann
Veteran
Posts: 11800
Joined: Wed Jan 22, 2020 6:03 pm
Location: Osnabrück DE 🇩🇪
Contact:

Re: (WORKAROUND) incomplete ifc export. operating error?

Post by thomas-neemann »

bernd wrote: Tue Mar 28, 2023 8:18 am ...
That's true, but that's also dangerous with solids, e.g. it is not checked whether there are overlaps and multiple parts.
Gruß Dipl.-Ing. (FH) Thomas Neemann

https://www.youtube.com/@thomasneemann5 ... ry=freecad
User avatar
bernd
Veteran
Posts: 12849
Joined: Sun Sep 08, 2013 8:07 pm
Location: Zürich, Switzerland
Contact:

Re: (WORKAROUND) incomplete ifc export. operating error?

Post by bernd »

For sure ... just because one delivers solid geometry does not mean the geometry does not have any problems ... ;)

But for some workflows you just need solid geometry and even more like opening objects etc ...
User avatar
thomas-neemann
Veteran
Posts: 11800
Joined: Wed Jan 22, 2020 6:03 pm
Location: Osnabrück DE 🇩🇪
Contact:

Re: (WORKAROUND) incomplete ifc export. operating error?

Post by thomas-neemann »

bernd wrote: Tue Mar 28, 2023 8:57 am ...
is correct. i will try to create only solids in the future. but if quick changes are needed, e.g. from one meeting to the next in a few minutes, then faces are unbeatably fast
Gruß Dipl.-Ing. (FH) Thomas Neemann

https://www.youtube.com/@thomasneemann5 ... ry=freecad
User avatar
yorik
Founder
Posts: 13640
Joined: Tue Feb 17, 2009 9:16 pm
Location: Brussels
Contact:

Re: (WORKAROUND) incomplete ifc export. operating error?

Post by yorik »

In theory, IFC objects are not required to be solids. However, it seemed to be a good practice to enforce it, because in the reality there is no physical object that is not solid (besides a sheet of paper maybe, and even so it actually is a solid :) ). IIRC, though, if you turn the Brep flag on for your object, (in Utils menu), it will export even if the object is not solid.

However if your compound DOES contain solids (and other faces), then indeed only the solids will be exported.

Maybe we need an additional, forceFaces flag? :)
User avatar
thomas-neemann
Veteran
Posts: 11800
Joined: Wed Jan 22, 2020 6:03 pm
Location: Osnabrück DE 🇩🇪
Contact:

Re: (WORKAROUND) incomplete ifc export. operating error?

Post by thomas-neemann »

yorik wrote: Tue Mar 28, 2023 9:08 am ...
Thanks for the feedback. if I set the flag, how do I know it worked? the ifc from it is still a wireframe
Bildschirmfoto_2023-03-28_11-49-12.png
Bildschirmfoto_2023-03-28_11-49-12.png (51.68 KiB) Viewed 4222 times
Gruß Dipl.-Ing. (FH) Thomas Neemann

https://www.youtube.com/@thomasneemann5 ... ry=freecad
User avatar
bernd
Veteran
Posts: 12849
Joined: Sun Sep 08, 2013 8:07 pm
Location: Zürich, Switzerland
Contact:

Re: (WORKAROUND) incomplete ifc export. operating error?

Post by bernd »

https://github.com/FreeCAD/FreeCAD/blob ... 2190-L2195

shells or lonley faces not belonging to a solid inside one object will not be taken into account for ifc export. A shell in a own object will be exported.
User avatar
thomas-neemann
Veteran
Posts: 11800
Joined: Wed Jan 22, 2020 6:03 pm
Location: Osnabrück DE 🇩🇪
Contact:

Re: (WORKAROUND) incomplete ifc export. operating error?

Post by thomas-neemann »

bernd wrote: Tue Mar 28, 2023 9:59 am ...
wonderful. 1000 thanks. a nice example of how quickly a "problem" can be solved in open source.
Gruß Dipl.-Ing. (FH) Thomas Neemann

https://www.youtube.com/@thomasneemann5 ... ry=freecad
User avatar
bernd
Veteran
Posts: 12849
Joined: Sun Sep 08, 2013 8:07 pm
Location: Zürich, Switzerland
Contact:

Re: (WORKAROUND) incomplete ifc export. operating error?

Post by bernd »

yorik wrote: Tue Mar 28, 2023 9:08 am Maybe we need an additional, forceFaces flag? :)
good idea

we could even export wires like this ... At work ATM I am testing exporting polylines as axes for survey the building site. We are in a real POC where we do build without any drawing only with the BIM model. We would like to even NOT use any dwg or dxf. The aim is just to use ifc data. ATM the problem ist about survey axes.
User avatar
bernd
Veteran
Posts: 12849
Joined: Sun Sep 08, 2013 8:07 pm
Location: Zürich, Switzerland
Contact:

Re: (WORKAROUND) incomplete ifc export. operating error?

Post by bernd »

thomas-neemann wrote: Tue Mar 28, 2023 10:03 am
bernd wrote: Tue Mar 28, 2023 9:59 am ...
wonderful. 1000 thanks. a nice example of how quickly a "problem" can be solved in open source.
It does not solve it ... It just shows where all this is happening in the code ... 8-)
Post Reply