topic Re: Export IFC with local East/North coordinates but real world Z (sea level) coordinate in Collaboration with other software

Export IFC with local East/North coordinates but real world Z (sea level) coordinate

CarlM — Wed, 08 Jan 2025 09:40:27 GMT

Hi,

I am trying to export an IFC-model with our local coordinates, but the real world z-value (defined with sea level).
Can this be done? - I can only find using either strict Surveu Point, or Project Origin in the IFC- translator (Geometry Conversion for IFC Export/Define IFC model position by:).

Or do you have to do a manual z-move of the model before export by the sea level value?

Looking forward to hearing your recommendations/suggestions!

Thanks!

Operating system used: Windows

Re: Export IFC with local East/North coordinates but real world Z (sea level) coordinate

CosminF — Wed, 08 Jan 2025 10:08:36 GMT

Hi!

You can try adding a Survey Point and define the parameters for IFC there, it may help:

Re: Export IFC with local East/North coordinates but real world Z (sea level) coordinate

CarlM — Wed, 08 Jan 2025 10:18:42 GMT

Hi!

Thanks for your quick reply!

I have the SP defined - I export dwg's in real world coordinates, but in this case I need the local X and y coordinates but the real world (sea level) z-coordinate in the IFC model.

Re: Export IFC with local East/North coordinates but real world Z (sea level) coordinate

CosminF — Wed, 08 Jan 2025 10:23:44 GMT

So you need a hybrid display (local + global) - it was a misunderstanding on my part then with my previous reply.

I do not know how you would achieve this, maybe a feasible workaround would be to use global coordinates everywhere but mark the origin point at 0.0 (I just learned about it, the place called Null Island) and the Z value you desire. Then the X Y local would match X Y Global. But your project wouldn't be georeferenced anymore.

Re: Export IFC with local East/North coordinates but real world Z (sea level) coordinate

CarlM — Wed, 08 Jan 2025 12:31:04 GMT

Yes - a hybrid. But I want to work near local origin, not in the real world coordinates (too far away).

I guess I'll have to export the IFC, merge it in a new instance of Archicad, elevate the entire model to the correct real world z-value, amnd save it as an IFC again.

Re: Export IFC with local East/North coordinates but real world Z (sea level) coordinate

Laszlo Nagy — Sun, 12 Jan 2025 13:57:18 GMT

On the Learn Portal, there is a Workflow Guide about the Native Survey Point in Archicad, which covers this topic in detail.