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For software developers · 3D InterOp SDK

Convert Parasolid to VDA-FS in your application

3D InterOp is a CAD interoperability SDK that lets your software read Parasolid files and write VDA-FS, 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 Parasolid · Writes VDA-FS
  • Exact geometry → exact geometry
  • C++ / C# APIs
bracket.x_tParasolid · exact B-Rep
Your application
3D InterOp SDK
Parasolid readerHealingVDA-FS writer
panel.vdaVDA-FS 2.0 · surfaces

Parasolid to VDA-FS at a glance

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

Parasolid (source)VDA-FS (target)
Full nameParasolid transmit file (text X_T, binary X_B)VDA surface interface
Standard / ownerProprietary — SiemensVDA (German automotive industry)
File extensions.x_t, .x_b, .xmt_txt, .xmt_bin.vda
GeometryExact B-RepExact curves and surfaces
Assemblies / structureYes (Parasolid assembly structure)No assembly hierarchy
3D InterOp supportRead and write · up to Parasolid 38Read and write

What's preserved, what changes

Here is what your application can expect to carry across from Parasolid to VDA-FS.

  • Preserved
    Exact geometry
    Solids and surfaces stay exact B-Rep. The model is never reduced to a triangle mesh.
  • Changes
    Assembly structure
    VDA-FS has no native assembly hierarchy. Decide in your application how Parasolid product structure is grouped or flattened before writing.

Why software vendors add Parasolid to VDA-FS conversion

Legacy CAD and CAM systems

Many established engineering tools still consume VDA-FS first. Writing it lets your users hand data to them without leaving your application.

Supplier and partner exchange

Some suppliers and manufacturing partners still specify VDA-FS in their exchange requirements. Your software can meet them directly.

Geometry-only workflows

When a downstream process needs exact part geometry and nothing more, VDA-FS is a simple, widely readable target.

Things to check before you ship

  • Written VDA-FS versions: VDA-FS 2.0.
  • The VDA-FS writer isn’t available in 3D InterOp CGM.
  • Supported Parasolid input: Parasolid 9.0 to 38.0.
  • 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 Parasolid (X_T) file?

    Parasolid is the geometric modeling kernel developed by Siemens and used by many CAD, CAM and CAE applications. Its transmit files store exact B-Rep models as text (.x_t) or binary (.x_b).

  • Target format

    What is a VDA-FS (.vda) file?

    VDA-FS is a neutral surface-exchange format defined by the German automotive association VDA. It stores exact curves and free-form surfaces, and is still found in automotive supply chains.

Frequently asked questions

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

No. The VDA-FS writer isn’t available in 3D InterOp CGM.

Yes. 3D InterOp reads Parasolid text (.x_t, .xmt_txt) and binary (.x_b, .xmt_bin) files.

3D InterOp reads Parasolid 9.0 to 38.0.

3D InterOp writes VDA-FS 2.0.

Yes. 3D InterOp reads and writes both formats, so VDA-FS to Parasolid is supported too.

  • Building software that needs to convert Parasolid to VDA-FS?

    3D InterOp is an SDK that lets your application read Parasolid and write VDA-FS alongside 30+ CAD and BIM formats.