1)   3DM Import for AutoCAD 1.0 3DM Import for AutoCAD is a Rhino 3D Model / OpenNURBS 3DM file import plug-in for AutoCAD. This plug-in gives AutoCAD the ability to import geometric data from 3DM files. 2)   Terrain for Rhino 3.0 1.0 Terrain for Rhino is a terrain modeling plug-in for Rhinoceros (commonly known as Rhino). This plug-in gives Rhino the ability to create a terrain mesh from a set of unordered points.