IFC Georeferencing with Archicad 26

[Guisn21]

Hey lads! I have tried using many different settings to export an IFC 4 which would carry the georeferencing information with it (IFC Georeferencing Paramaters), to no success. The Archicad Manual says that IFC4 would automatically generate the ifcmapconversion and ifcprojectedcrs entities to allocate this info, but my ifc files do not follow the manual's instructions.
Any insights on this matter?
Cheers!

Operating system used: Windows 11

 

[Guisn21]

👀

[JSN]

Did you succeed?

You need to specify the CRS name correctly with 'EPSG:3763' like in https://epsg.io/3763 plus you also need to to add this information to Map Projection / Projecao do Mapa and additional Zone Information if you have them.

[scottjm]

What IFC translator Geoentry Conversion settings are you using? 

How are you checking the IFC file does or does not include the geo referencing ?

[JSN]

@scottjm what software do you recommend for for checking the correct georefernce data?

I used KIT, formerly FZK, viewer where you can load additional Data like OpenStreet Data ... but currently I alsways get an offset of 20-50m though the IfcMapConversion seems to match the survey data. It's the same for a file created with Revit so I am beginning to doubt the integrity of either the one or the other. That's why I wanted to ask you what options are there to quickly check if an IFC is valid for GIS usage? What are you using?

[scottjm]

I use solibri and place a co-ordinate markup at the known permanent survey point marker location ( which I usually model as a small upside down pyramid) to cross check the eastings and nothing match what the Map Grid of Australia Co-ordinates are. 
im not 100% sure if EPSG map grid system works the same way though. 

I’ve not heard of KIT. 

I did notice you have an 85deg rotation set. Just confirm you have taken that into account when positioning the survey marker. (Although if you hadn’t I would expect the difference to be 1000s of km different not only 25m)

[JSN]

Solibri is not able to work with IfcMapConversion.

I am not really familiar with the Australian datums but what you describe is sounds different.

Have also a look here:

https://www.google.com/url?sa=t&source=web&rct=j&opi=89978449&url=https://www.buildingsmart.org/wp-c...

I am not OP so the above example is not mine. I just have a different problem related to this topic and that's why I ended up here. In any case rotation is of course a thing but in the screenshot above the 85,10 is the elevation. There is no information given about it fand due to the fact that the central axis for the rotation is supposed to be much closer to the site it could indeed be only a few meters.

To be more precise, I have not such a rotation problem but a constant offset of all elements to the north which is not depicted here anywhere at the moment.