Read COLLADA DAE for OBJ output
A COLLADA DAE-to-OBJ workflow connects the COLLADA DAE reader to the OBJ writer. Select the model items and output representation needed by the receiving application.
Read the DAE asset with the Assimp integration and inspect the geometry and scene hierarchy available to the application. Resolve the resources used by the source materials.
Prepare polygonal geometry for OBJ
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.
Write the selected surface mesh with the OBJ interface. Establish whether the consumer needs per-part grouping, normals or supported appearance information, and preserve any associated material resources produced by the writer. A polygon file is not a replacement for the full CAD document.
Check the OBJ result
Check nested transforms, scale and supported appearance. This integration guide covers mesh, colors, materials and structure; it does not imply transfer of every authoring or animation feature of COLLADA.
Check the OBJ in the receiving graphics or geometry tool, including scale, face orientation, grouping and companion-file references. Where a flat mesh cannot retain the original assembly relationships, keep that engineering information separately.
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.