When converting IFC files to SVF with the Autodesk Model Derivative API, I would like to start using the "modern" converter instead of the "legacy" one. However, when using Forge Viewer, the models that were created with the modern conversion method end up with a different position and/or orientation than the legacy ones.
I have tried to get to the bottom of what the difference consists of, and it seems to at least have something to do with the TrueNorth
property of the IfcRepresentationContext
in the IfcProject
. Also, the ObjectPlacement
of the IfcSite
is probably part of it. But I haven't found a combination of properties to reliably compensate for the difference for all my IFC files. The IFCs typically come from Revit, but may have various origins.
Many of our customers have projects with several existing models, so ideally, any new models should align with the existing ones even if the conversion method has changed.