Prepare AC3D geometry for FBX
The AC3D-to-FBX route uses the AC3D reader, mesh preparation and the FBX writer. Choose the geometry and representation required by the destination application.
Read the AC3D .ac mesh asset through the Assimp integration. Inspect object structure, polygon geometry and the material data returned by the reader.
Prepare mesh geometry for FBX delivery
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 mesh geometry with the commercial FBX interface. Prepare the supported scene and placement mapping required by the receiving application. Check appearance and other attributes individually rather than assuming all source properties have an FBX writer mapping.
Validate the converted model
Compare grouped objects, placements and supported colors or materials. Keep source resources available and verify the appearance expected by the recipient.
Reopen the FBX in the destination and compare scale, orientation, geometry coverage and placements. Verify the actual version and property mapping needed by that application. Retain the engineering source for information that the scene derivative cannot carry.
For repeated jobs, retain the source, preparation settings and representative output checks. Discuss this conversion with the input files, destination application and required geometry and attributes.