File Transfer Archicad to Rhino, keeping surfaces

Is it possible to export an Archicad (18) file to Rhino, without meshing the geometry?

I guess that is a question you should ask Graphisoft.
This page shows that they export 3D in the DWG format but the link to the details is dead.

Native AutoCAD DWG files does not support NURBS geometry and as such, I would assume that the answer is no. But again, they should be able to answer this.

There is also this… --Mitch

If you’re happy to use a plugin, then you can export to IFC in Archicad, and then import into Rhino using the Geometry Gym importer. Install ggRhinoIFC from (Mac or Windows)

This will then generate light weight extrusions (where applicable) generating a higher performing model. If objects are revolutions and Archicad utilizes the IFC shape representation where possible and polysurfaces can have multiple perimeter segments (rather than meshing to quads and triangles).

Native DWG does support Nurbs (the ACIS variety), but I don’t believe Archicad has nurbs so that’s not relevant. If you have morphed objects in Archicad, that will be a mesh, although I do have some options to utilize the merge planar faces (and am working on optimizers to do this step).

If you have any questions or need advice, if you can share a file with me I can advise.



1 Like

I just quoted from the Rhino help file.

Warning: Surfaces and polysurfaces will come into AutoCAD as either curves or meshes because the native AutoCAD DWG files does not support NURBS geometry.

If this is wrong, @margaret should know about that so that it can be corrected.

Yes, that’s definitely outdated, since V5 or so, you can export Breps as (ACIS) “solids”.

1 Like

Misunderstanding. The help file doesn’t say that Rhino cannot. It says ‘AutoCAD’ and ‘native’. I took that to mean that the original format didn’t support NURBS. Since I was arrested for using the wording as it was, I am just trying to find out if the help file is correct or not. My interpretation of the words can also be wrong and in that case perhaps the wording could be changed.

@lowell Lowell, can you verify this wording or give me a correction, please?

AutoCAD supports nurbs geometry and Rhino exports nurbs surfaces as such if your export scheme is set to "Export Surfaces as Solids"
In AutoCAD, the objects will list as Solid or Surface

1 Like

Does that mean you would rather take out this text in the Rhino help file?

Yes, it’s incorrect.


Here is the answer

I have seen that the previously mentioned link is no longer valid Graphisoft have remapped their site. So the new possible links that you may want to check are:

  1. ArchiCAD: Import/Export File Formats in ARCHICAD

  2. ArchiCAD: Import Rhino Model

  3. ArchiCAD: Import IFC Model to ARCHICAD