Convert 3DXML to STL in your application
3D InterOp is a CAD interoperability SDK that lets your software read 3DXML files and write STL, carrying the mesh data across without re-tessellating it.
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 3D XML · Writes STL
- Triangle mesh → triangle mesh
- C++ / C# APIs
3DXML to STL at a glance
Both formats store triangles, so the facets carry over without re-tessellation. The differences are in structure, appearance and metadata.
| 3D XML (source) | STL (target) | |
|---|---|---|
| Full name | 3D XML | Stereolithography |
| Standard / owner | Dassault Systèmes | Open format |
| File extensions | .3dxml | .stl |
| Geometry | Tessellated geometry | Triangle mesh |
| Assemblies / structure | Yes | No |
| PMI | Graphical PMI | None |
| 3D InterOp support | Read and write | Read and write |
What's preserved, what changes
Here is what your application can expect to carry across from 3D XML to STL.
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Preserved
Mesh dataThe 3DXML facets are read and written to STL without being re-tessellated.
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Changes
Assembly structureSTL has no native assembly hierarchy. Decide in your application how 3D XML product structure is grouped or flattened before writing.
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Not carried
PMISTL has no place for PMI, so the PMI read from 3DXML isn’t written.
Why software vendors add 3DXML to STL conversion
Additive manufacturing
STL is still the input most slicers and print services expect. Writing it lets your users send parts to print directly.
Mesh-based processing
Inspection, scan comparison and mesh-editing tools work on triangles. A mesh output gives them a model they can open anywhere.
Lightweight sharing
A mesh is simpler than the native CAD file and needs no CAD system to open.
Things to check before you ship
- Supported 3DXML input: 3D XML 4.0 to 4.3 (tessellated data only).
- B-Rep stored in authoring-mode 3D XML files isn’t imported: only the tessellation is read.
- Test tessellation settings on your heaviest parts: finer meshes mean larger files.
- 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 3D XML (.3dxml) file?
3D XML is Dassault Systèmes’ lightweight XML-based format for sharing 3D product data. 3D InterOp reads and writes its tessellated representation, with product structure and graphical PMI.
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Target format
What is an STL file?
STL describes a 3D surface as a set of triangles, with no units, materials or assembly structure. Its simplicity makes it the usual input for 3D printing.
Frequently asked questions
No re-tessellation is needed. 3D InterOp reads the 3DXML facets as visualization data and writes them to STL.
STL has no place for PMI, so the PMI read from 3DXML isn’t written. Your application can still access it after import, or offer STEP AP242 as an output.
STL has no assembly hierarchy, so your application decides how the 3DXML structure is grouped or flattened before writing.
No. STL stores triangles only, with no units, colors or textures. Agree on the unit with the application that reads the file; the 3D InterOp STL reader assumes millimeters.
No. B-Rep stored in authoring-mode 3D XML files isn’t imported: 3D InterOp reads the tessellation only.
3D InterOp reads 3D XML 4.0 to 4.3 (tessellated data only), as visualization data.
Yes. 3D InterOp reads and writes both formats, so STL to 3DXML is supported too.
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Building software that needs to convert 3DXML to STL?
3D InterOp is an SDK that lets your application read 3D XML and write STL alongside 30+ CAD and BIM formats.