How is Rhino able to import dwg

[Daniel_Krajnik]

There are few programs outside autodesk’s product line that are able to import dwg files without converting them to dxf first. I am wondering how is rhino able to do it?

[menno (Menno Deij - van Rijswijk)]

Probably by reverse engineering the file format, as it is not an open/libre file format, but proprietary Autodesk.

[Daniel_Krajnik]

Could someone please confirm it?

If that’s true would there be any chance for Rhino to release this work? It would be incredibly useful for others.

[fraguada (Luis Fraguada)]

Rhino uses OpenDesignAlliance’s DWG library: https://www.opendesign.com/
McNeel was a founding member of the OpenDesignAlliance Customers | Open Design Alliance

[Daniel_Krajnik]

Perfect, thank you

[Daniel_Krajnik]

@fraguada a follow-up question would be why is it not available in Grasshopper?

[dale (Dale Fugier)]

@Daniel_Krajnik

why is it not available in Grasshopper?

Make a C# component that calls RhinoDoc.Import.

– Dale

[fraguada (Luis Fraguada)]

You can also use the Params > Input > Import3DM component:

[Daniel_Krajnik]

@fraguada true, I’ve tried that, but a lot of objects were lost using this method (blocks or blocks within blocks)

@dale thanks, I need to test it