IFC Properties for Geo-referencing in Cesium Ion

Cesium ion
1

Hello,

I would like to know which properties within an IFC file are used for geo-referencing when it’s converted to 3D Tiles using Cesium Ion. I have several geo-referenced files, but almost none of them are placed at the correct position or with the correct scale, so I’m wondering what the problem could be.

Thanks a lot!

Best regards,
Luca Rath-Heel

2

Hi,

Can you please share an asset id or some sample data with us, we can take a look at what could be going wrong. Please also provide the input that you are passing as the EPSG code when picking the tiling options.

Thanks,
Ankit

3

Hi,

thanks for your quick reply!
I have uploaded the same file three times:

  • asset 3663336 (no epsg)
  • asset 3663335 (epsg 4326)
  • asset 3663332 (epsg 2056)

I kept the default values of all the other options.
The correct coordinates are provided in the IFCSITE property of the IFC file.

Thank you for having a look!

Best regards,
Luca

4

Hi Ankit,

we are currently evaluating using Cesium Ion in production and this is an essential part of our usecase, therefore I would highly appreciate if you could take a look and let us know, if this is a problem with our assets or with your converters.

Thank you very much!

Best regards,
Luca

5

Hi,

The Cesium tiler doesn’t currently use the IFCSITE property when processing files. Instead, it relies on the coordinate system specified in the UI or in the IFCPROJECTEDCRS property. Support for IFCSITE may be added in a future update, so feel free to keep an eye out for that.

Regarding the file you’re trying to tile asset 3663332 should have worked when EPSG 2056 was provided, but I noticed it’s not appearing in the correct location. I’ve opened an issue with our team to investigate further.

7

Hi,

thanks for having a look!

Best regards,
Luca