IFC with exactly same export options are showing in different rotations in Model coordination view

[Naumanen]

Hi all. 

We are having an issue where two ifc files of the same building, exported with the same options from Tekla, are showing in different rotations in the Model coordination view. We want to show our buildings in true north. 

Naumanen_0-1726143927866.png

We have been testing this out and this ifc is showing correctly in every other ifc viewer except in ACC. 

Any idea what could be the reason for this behavior and how to fix this?

[Naumanen · Accepted solution]

Hi all.

I solved this problem by writing a program in Visual Studio which compares two .txt-files. It seems there was a weird difference on the lines 10 and 11. The ifc which worked fine had the lines: 

#10= IFCAXIS2PLACEMENT3D(#6,#9,#7);

#11= IFCDIRECTION((0.,1.));

And those which didn't work had the lines:

#10= IFCAXIS2PLACEMENT3D(#6,#9,#7);

#11= IFCDIRECTION((0.569279523430877,0.822144041030715));

So I just edited the text-files, replaced the row 11 with the text IFCDIRECTION((0.,1.));, saved as ifc file and uploaded into Autodesk Construction Cloud and now they are working as intended. 

Hopefully this will help anyone facing similar issues.