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For software developers · 3D InterOp SDK

Convert 3DM to CATIA V4 in your application

3D InterOp is a CAD interoperability SDK that lets your software read 3DM files and write CATIA V4, with exact B-Rep geometry carried across and nothing tessellated.

Spatial does not offer an online converter or a desktop conversion app. 3D InterOp is a component that software vendors embed in their own products.

  • Reads Rhino · Writes CATIA V4
  • Exact geometry → exact geometry
  • C++ / C# APIs
shape.3dmRhino · NURBS surfaces
Your application
3D InterOp SDK
Rhino readerHealingCATIA V4 writer
part.modelCATIA V4 · exact B-Rep

3DM to CATIA V4 at a glance

Both formats store exact geometry, so the model stays exact. The differences are in the product data each one can carry.

Rhino (source)CATIA V4 (target)
Full nameRhinoceros 3D modelCATIA Version 4
Standard / ownerRobert McNeel & AssociatesDassault Systèmes
File extensions.3dm.model, .exp, .session
GeometryExact NURBS geometry and meshesExact B-Rep
Assemblies / structureNo assembly hierarchyYes (written as parts only)
3D InterOp supportRead onlyRead and write

What's preserved, what changes

Here is what your application can expect to carry across from Rhino to CATIA V4.

  • Preserved
    Exact geometry
    Solids and surfaces stay exact B-Rep. The model is never reduced to a triangle mesh.

Why software vendors add 3DM to CATIA V4 conversion

Deliver in your customer’s CAD format

Aerospace and automotive OEMs often require supplier data in CATIA V4. Writing it lets your users meet that requirement directly from your application.

Exact geometry, ready to edit

CATIA V4 keeps exact B-Rep geometry, so the receiving engineer can measure, modify or machine the model in CATIA.

No neutral-format round trip

Writing CATIA V4 directly avoids an extra STEP or IGES step, and the loss each extra translation can add.

Things to check before you ship

  • Written CATIA V4 versions: CATIA 4.1.9 to 4.2.4 (.model).
  • The CATIA V4 writer isn’t available in 3D InterOp CGM.
  • Supported 3DM input: Rhino 2 to 8.
  • Validate a sample of translated files in the target system your users actually work with.

Working with Spatial was a real milestone for us: Thanks to the powerful 3DInterOp library, we were able to successfully bring our complex CAD-based solutions to the cloud while remaining flexible to meet individual customer requirements. For us, Spatial is not just a technology partner, but a true enabler of our product strategy.

Dr. Arno Michelis, Founder, Simus Systems

Read the Case Study

About the formats

  • Source format

    What is a 3DM (.3dm) file?

    3DM is the native file format of Rhinoceros (Rhino), the NURBS modeler from Robert McNeel & Associates. It stores exact curves, surfaces and solids, as well as meshes.

  • Target format

    What is a CATIA V4 (.model) file?

    CATIA V4 is the legacy generation of Dassault Systèmes’ CATIA, whose models are mostly stored in .model files. Many aerospace and automotive archives still hold CATIA V4 data.

Frequently asked questions

Yes. Both formats store exact B-Rep geometry, so the model is translated without being tessellated into triangles.

No. The CATIA V4 writer isn’t available in 3D InterOp CGM.

No. 3D InterOp reads Rhino geometry, but importing mapping data isn’t supported.

3D InterOp reads Rhino 2 to 8.

3D InterOp writes CATIA 4.1.9 to 4.2.4 (.model).

No. 3D InterOp reads 3DM but doesn’t write it. To send data back to Rhino users, write a neutral format they can import, such as STEP.

  • Building software that needs to convert 3DM to CATIA V4?

    3D InterOp is an SDK that lets your application read Rhino and write CATIA V4 alongside 30+ CAD and BIM formats.