Cleaning up FBX imports for baking and realtime use

Follow the instructions in this article to clean up FBX models imported into 3ds Max for export to Vizard. These modifications should be made in the order listed:

  1. Select all geometry and use Tools->Snapshot (set to Single/Mesh). When it makes the new copy, hit delete to get rid of the original. This helps fix any corrupt meshes. Corrupt meshes can cause Max to crash or exhibit strange behavior, and can also increase export time in some cases.
  2. Select all geometry and use "turn to poly" with Limit Polygon Size set to 3. This keeps curved surfaces (generally pipes & railings) from losing their shape when collapsed later.
  3. Use the "Reset XForm" utility to flatten the transforms, then collapse the geometry to editable poly. This helps fix issues caused by scaled models. Even after this step, sometimes FBX imports will still have issues when rescaled.
  4. The model may now look strangely lit, due to bad normals. Add an Edit Normals modifier. Most normals shown will appear green, showing that they're explicit. Click on the modifier's name to get into normal selection mode, hit Ctrl+A to select all, then hit Reset. They should all turn blue. Convert the model to editable poly. Bad normals make the lighting look strange, cause baking issues, and cause issues with any Vizard programming that aligns a model to a surface.
  5. Smooth the normals using the Smooth modifier set to 30. Some objects may need their smoothing groups set up manually if the automatic smoothing doesn’t give the desired result. If you see any strange lighting at this point, the model probably has some unwelded vertices or other similar mesh issues.
  6. Select all objects, go to properties, and enable backface culling if it isn't already on. If any models appear to be inside out, use the modifier called Normal. This is different from the edit normals modifier. Alternatively, you can use the flip normals tool within Editable Poly. Flipped normals can often cause baking problems (model's texture renders black).
  7. If you see flickering on a surface in the viewport, then two faces are occupying the same space or are too close together (z-fighting). You may need to move or remove one of the faces.