Shared coordinates and IFC link positioning

[m.zygaitis]

Hello,
I have this issue:

Some models share same coordinates that are quite far away from origin. Survey point stands at 000, project point at A1 grid intersection (some point on planet with many numbers). I made this possible by acquiring coordinated from dwg topography. Models align then linked perfectly.

However, then I link IFC (there are no settings in link IFC dialog), it places linked file (exported from Civil 3D) much further than it should be, probably twice as far. I tried exporting my models to ifc and putting it in tekla bim sight – everything aligns perfectly. I even opened IFC in Revit in a separate file, checked coordinates, everything is correct.

I tried linking revit (with IFC open in Revit). Every possible insertion option gets me the same result. I tried to move project base point to know location (A1 intersection point). Had super difficult time. Revit can not move unpinned project point more than 19km.

Am I missing something?

Could you share a workflow?
Thank you.

[onBIM-Consulting]

Revit have three points instead two. The project base point, survey point and internal point ("absolute 0,0,0"). IFC files use this point as reference. When you moved your project base point the internal was not moved (it not moveable). The IFC file base point remains the internal. What you need to do is maintain this in mind when coordinate projects with IFC files.

[Magnus.B]

I have struggled with this issue for a long time and so far my conclusion is that it is impossible to import IFC files exported in shared coordinates back to Revit. (or any other IFC file exported with real world coordinates)

They can't be placed at site zero . 

Example of IFC file with large coordinates beeing linked in Revit. It simply can't be moved to correct position

[Anonymous]

I'm having the same issue - I tried everything and nothing really works.
Did you find a solution ? how did you proceed to link IFC correctly to your models ?  Thank you in advance, @m.zygaitis @Magnus.B 

[Magnus.B]

@Anonymous Sorry but the only solution I have is to ask for a different export. 😞

[maxx.blake]

This is a joke - AutoDesk can't expect multiple Planers to have the same Internal Origins when project setup varies GREATLY between offices.

Have you found a solution to this? We have the same problem in our office...

IFCs are in the correct position in Solibri - the wrong position in Revit.

When we like the Native Revit Files by Shared Coordinates, they are in the correct position.

However, our two collaborators have different Internal Origins, which is causing the discrepancy. I.e. when Revit links an IFC it can only link by Origin to Origin... what a disaster...

[Anonymous]

The only way to import an IFC into Revit and to position it correctly is to move your IFC once imported, by using the Dynamo script in this post : https://knowledge.autodesk.com/fr/support/revit-products/learn-explore/caas/simplecontent/content/re...

Disaster indeed...

[EugenijusJanuskevicius6305]

The other solution is more simple:

1. Link IFC as usual;
2. Reveal the internal origin point. It will appear both for the project and the linked IFC (actually, RVT) file;
3. Move the linked IFC file, its internal origin to the project base point.

Not sure, but seems the angle to the True North is preserved.

[jdick_elsman_infranea]

also @EugenijusJanuskevicius6305 

For Civil3D IFC linking, there is a better alternative, since Civil3D is not able to export anything other than real world coordinates to IFC. 

Before doing this, I strongly recommend to have all ifc parameters that are exported as well obtained in the shared parameter file of your project, or to create a separate IFC sharedParameter file.

NB! I only tested this workflow with principle that the entire project is working on real world coordinates, and not on some relative coordinates based on some position in your project site. (project basepoint is setup in real world coordinates, surveypoint is setup on (XYZ)(0,0,0)

First things first:

- Create a clean template in the same coordinate system as your project

- Save it to something recognizable like <templateName>IFC4C3DLink.rte

- Setup your project basepoint, surveypoint and internal origin on (XYZ)=(0,0,0) Representing the origin of your coordinate system. 

- Save and close your template

Steps to take (2020 series):

- Open your Revit project

- Go to File>Open>IFC options

- Select the previously setup template using the browse button on the top-right corner of the IFC options settings

- Press "OK" to save the settings

- Export Civil3d file to .ifc file with IFC4 settings as <filename>.ifc

- Duplicate the sharedparameter file with the ifc paramters to the same file location as from which you are going to create the ifc link as <filename>.ifc.sharedparameter.txt

- In the open Revit project (in which you want to link), go to tab insert>link IFC

- Select the desired IFC from Civil3D to link 

VOILA!

Optional steps:

In the load-action, Revit creates a shadow .rvt file. In order to properly use viewfilters, you can unload the IFC and then reload the .rvt shadow copy. Updating this file with new ifc exports only requires opening the shadow .rvt file!

Hope this helps!

[jdick_elsman_infranea]

Edit:
In 2021 Revit seems to auto transform real world coordinates of solids relative to Internal Origin of the project.. In this version your IFC template needs the Internal Origin setup on your project basepoint coordinate..

[marie-pierre.lebelXBW9B]

This is interesting, but when I try moving my project base point to the origin of coordinate system, I get a message saying the PBP cannot be placed more than 10 miles away from its startup location (Revit 2020).  No luck here.

[luisPDAN6]

When linking using Link IFC Pro one can choose where to position the IFC, either on the base point, survey point or on the internal point.