File Formats: Import and Export

July 1, 2026 · View on GitHub

Export floating window

3MF (Feature Aware)

  • 📤 Export: Generates a 3MF container that includes triangulated geometry plus an embedded copy of the feature history at Metadata/featureHistory.json. PMI views (camera, view settings, and annotations) are part of that history, and when views exist the exporter also writes labeled PNG captures to /views/<view-name>.png with relationships from the package root. Multiple solids export as separate objects in a single file. Units are configurable (default millimeter). Non-manifold solids are skipped with a notification, but the export proceeds.
  • 📥 Import: Loads 3MF files and restores the embedded feature history when present. If no history is stored, the geometry imports as editable mesh only.
  • Compatibility: The extra history metadata is ignored by other 3MF viewers, but the file remains valid.

STL

  • 📤 Export: Writes ASCII STL. If multiple solids are selected, the dialog produces a ZIP archive with one STL per solid. Unit scaling applies at export time.
  • 📥 Import: Supports ASCII or binary STL. Imports as geometry only without feature history.

OBJ

  • 📤 Export: Writes ASCII OBJ (ZIP with one OBJ per solid when multiple bodies are selected). Unit scaling applies at export time. An export-dialog checkbox can optionally include vertex colors (v x y z r g b).

STEP

  • 📤 Export: Writes ISO 10303-21 .step files using a faceted BREP representation from the current triangulated solids. Planar triangles are merged into larger polygon faces where possible.
  • Options: Unit scaling applies at export time. The export dialog can include faces, export boundary/adjacency edges as polylines, and optionally emit AP242 tessellated faces for non-planar regions.
  • Limitations: STEP export is mesh/faceted geometry, not the original parametric feature tree. Solids that cannot provide usable mesh data are skipped and reported, while the remaining solids still export.

BREP JSON

  • 📤 Export: Saves the feature history only as JSON (.BREP.json) with no mesh data. Useful for versioning or quick backups.
  • 📥 Import: Reloads the saved history and recomputes the model.

Sheet Metal Flat Patterns

  • The Sheet Metal workbench includes the FP Sheet Metal Flat Pattern Export button for DXF or SVG flat-pattern output.

Implementation Notes

  • 3MF exporter lives at src/exporters/threeMF.ts and packages geometry plus attachments through JSZip.
  • STEP exporter lives at src/exporters/step.ts.
  • 📤 Export dialog logic resides in src/UI/toolbarButtons/exportButton.ts.
  • 📥 Import button handling lives in src/UI/toolbarButtons/importButton.ts.
  • Feature history is embedded directly as JSON without XML conversion.
  • Face labels carry through export via per-object BaseMaterials, providing human-readable names in other tools. Materials and textures are not reconstructed on import.