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Technical Explanation

3DM is an open-source, extensible format that supports both geometric and non-geometric information — including metadata, layers, and user-defined attributes. Unlike polygonal file types (e.g., STL or OBJ) that approximate shapes using triangles, 3DM preserves mathematically accurate NURBS geometry for smooth, continuous surfaces.
Because of its open specification, the 3DM format can be processed by a wide range of CAD and visualization tools, such as Rhinoceros, Moment of Inspiration, SAP VEViewer, and Right Hemisphere Deep View.

This flexibility makes it a preferred choice for engineers, architects, and product designers who need interoperable precision data in their 3D workflows.


Applications and Industry Use Cases

  • Architecture and AEC/BIM – capturing complex freeform designs and organic geometries.
  • Industrial and Product Design – precise modeling of surfaces and fine details for consumer goods.
  • Additive Manufacturing – maintaining high-fidelity NURBS data before mesh tessellation.
  • Engineering and Simulation – enabling accurate data exchange with CAE and metrology systems.

Challenges or Common Pitfalls

While 3DM is designed for interoperability, its open nature doesn’t guarantee complete compatibility across all CAD systems. Converting between 3DM and formats like STEP, Parasolid, or ACIS can introduce geometry or topology inconsistencies, especially when translating complex NURBS data. Maintaining metadata and layer structures during conversion requires specialized translation
tools.

How Spatial Helps

Spatial’s 3D InterOp SDK delivers robust import and export capabilities for 3DM files, converting Rhino geometry, metadata, and topology into formats like ACIS or CGM with high fidelity. Combined with CGM Modeler or 3D ACIS Modeler, developers can integrate native 3DM data directly into their software solutions — ensuring precise, reliable, and efficient 3D interoperability across CAD, simulation, and manufacturing applications.

 

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