Convert Smart 3D to ASAT in your application
3D InterOp is a CAD interoperability SDK that lets your software read Smart 3D files and write ASAT, writing the Smart 3D facets as faceted geometry, since Smart 3D stores triangles rather than solids.
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 Smart 3D · Writes ACIS assembly
- Triangle mesh → faceted B-Rep
- C++ / C# APIs
Smart 3D to ASAT at a glance
Smart 3D stores triangles; ACIS assembly is an exact-geometry format. The mesh is written as faceted geometry: 3D InterOp doesn’t rebuild smooth surfaces from triangles.
| Smart 3D (source) | ACIS assembly (target) | |
|---|---|---|
| Full name | Hexagon (Intergraph) Smart 3D review files | ACIS assembly, text (ASAT) and binary (ASAB) |
| Standard / owner | Hexagon | Spatial (3D ACIS Modeler) |
| File extensions | .xml with its .vue | .asat, .asab |
| Geometry | Tessellated geometry | Exact B-Rep |
| Assemblies / structure | Yes: plant hierarchy (.xml) | Yes |
| 3D InterOp support | Read only | Read and write |
What's preserved, what changes
Here is what your application can expect to carry across from Smart 3D to ACIS assembly.
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Preserved
Product structureThe Smart 3D product structure is written to ASAT.
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Changes
Faceted geometrySmart 3D stores triangles, so the ASAT file holds faceted bodies, not solids. 3D InterOp doesn’t rebuild exact B-Rep from a mesh.
Why software vendors add Smart 3D to ASAT conversion
Hand models to kernel-based applications
Many CAD, CAM and CAE applications are built on the ACIS assembly kernel. Writing ACIS assembly gives them exact geometry they can load without another translation step.
Downstream modeling and analysis
An exact ACIS assembly B-Rep can still be edited, meshed or machined by downstream tools, which a tessellated export would not allow.
Exchange within one ecosystem
Partners whose tools share the ACIS assembly kernel often prefer to exchange ACIS assembly files directly.
Things to check before you ship
- Written ASAT versions: ACIS R18 to 2026 1.0.
- Supported Smart 3D input: the .xml file with its .vue file.
- Provide the .xml with its .vue file: a standalone .vue gives visualization data only.
- 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 StudyAbout the formats
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Source format
What is a Smart 3D file?
Hexagon Smart 3D is a plant and marine design system. Its models are shared as review files: a .vue file with the geometry and an .xml file with the plant hierarchy and properties.
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Target format
What is an ASAT (.asat) file?
ASAT and ASAB are the assembly versions of the ACIS save file, in text and binary form. They store the product structure of models built on Spatial’s 3D ACIS Modeler kernel.
Frequently asked questions
No. Smart 3D stores triangles, and 3D InterOp writes them to ASAT as faceted geometry. It doesn’t rebuild exact B-Rep from a mesh.
Yes. 3D InterOp reads the Smart 3D product structure and writes it to ASAT.
An ACIS assembly (ASAT/ASAB) doesn’t support layers or colors at instance level, suppressed or hidden instances, or units at instance level.
Provide the .xml file with its .vue file. A standalone .vue file gives visualization data only.
3D InterOp reads the .xml file with its .vue file, as visualization data.
3D InterOp writes ACIS R18 to 2026 1.0.
No. 3D InterOp reads Smart 3D but doesn’t write it. To send data back to Smart 3D users, write a neutral format they can import.
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Building software that needs to convert Smart 3D to ASAT?
3D InterOp is an SDK that lets your application read Smart 3D and write ACIS assembly alongside 30+ CAD and BIM formats.