Read 3MF for STL output
A 3MF-to-STL workflow connects the 3MF reader to the STL writer. Select the model items and output representation needed by the receiving application.
Read the mesh content available through the Assimp integration from the 3MF input. Inspect the imported object structure and appearance before constructing the target document.
Write the selected surfaces as STL triangles
The Assimp integration provides mesh geometry, colors, materials and scene structure for its supported inputs. Pass that data to a separate OCCT or commercial writer. For STEP, STEP XML or DXF output, use the mesh-capable representation; this does not reconstruct BRep surfaces from polygons.
Prepare triangulation for the selected geometry and write it with the OCCT STL interface. Set mesh detail for the destination task. STL does not retain the full assembly tree, names, colors or CAD metadata; keep the source model when those relationships matter.
Check the STL result
Check the geometry and placement of each imported item. Manufacturing settings and process-specific information require separate validation and should not be assumed to survive a geometry exchange.
Check unit scale, bounds, face orientation and connectivity in the receiving application. Include small features and curved regions in the comparison. Producing an STL file does not itself validate printability, watertightness or suitability for material removal.
Discuss this conversion with the producing and receiving applications, representative files and required geometry and attributes. Compare the reader/writer catalog when a different representation is needed.