Export IFC from Revit - Geolocation

PIX4Dcloud
1

Hi. What are the recommended settings in Revit to export data so that it “drops” in at the right spot? Using IFC4 and survey/base point doesn’t work properly in Cloud.

2

Hi,
I personally georeferenced BIM models and I would rather recommend exporting as IFC 2.3. However, please define the coordinates of your survey point so that they match the ones from Cloud. To do that, there are a few steps to consider:

  1. open your Revit project > go to the survey point > unclip the survey point > Manage > Coordinates > Specify Coordinates at Point.
  2. Specify Shared Coordinates > Enter the Northing (Y), Easting (X), Elevation, Angle to True North.
  3. in the IFC Exporter, click on Modify setup > select the Coordinate Base = Shared Coordinates

This always worked for me, but I was checking the point cloud origin in ReCap, before importing my point cloud into Revit and started modeling.

Hope this helps.

Cheers,
Teo

1 Like
3

Thank you. Looks like shared coordinates are working. However using shared coordinates is usually not recommended in the BIM world and other software we have happily accepts survey/basepoint. Hope Pix4D adresses this in the future as it will help make it easier to import IFC from external sources.

Revit also throws a warning about this.

Revit_Warning

4

Hello again,
How did you insert the point cloud in Revit? I use Origin to internal origin and this warning did not appear to me.
Best,
Teo

5

I didn’t use the point cloud from pix4d in revit. I’m talking about exporting from Revit to a IFC file that Pix4D cloud accepts. It doesn’t look like Cloud reads the base point or the survey point from the IFC file and needs to use shared coordinates in the export. However Shared coordinates is frowned upon in the BIM world as projects in UTM kan be very far from project 0,0 in BIM and can result in distortion and height errors.

Our workflow will mainly consist of building photogrammetry projects in Cloud and connecting different datasources from external clients (IFC, DXF, GeoJSON, etc) to make a finished “product” to examine.

6

Hi @Gromit83,

Thanks for sharing the detailed information about what you have in mind.

I don’t have more information to share with you for the moment. However, you can count on us to take into account your need for PIX4Dcloud to use the IFCPROJECTEDCRS and IFCMAPCONVERSION properties of your IFC4 design overlays so that they are displayed at the same location as your reconstrutions.

It isn’t possible to share a precise date by which that will happen, but you can count on me to inform you when PIX4Dcloud correctly handles your IFC files. Nevertheless, I am only human, so please also consider subscribing to PIX4Dcloud’s release notes, at Technical release notes - PIX4Dcloud / PIX4Dcloud Advance, to receive an email when there are new PIX4Dcloud features.