Limitations when importing from other applications

When Unity imports a proprietary file, it launches the 3D modeling software in the background. Unity then communicates with that proprietary software to convert the native file into a format Unity can read.

The first time you import a proprietary file into Unity, the 3D modeling software has to launch in a command-line process. This can take a while, but subsequent imports are very quick.

Warning: It is recommended that you export to FBX instead of directly saving your application files in the Project. It is not recommended to use native file formats directly in production.

Requirements

You need to have the 3D modeling software installed to import proprietary files directly into Unity. If you don’t have the software installed, use the FBX format instead. For more information about importing FBX files, see Model Import Settings window.

Application-specific issues

You import files in the same way, regardless of whether they are generic or proprietary files. However, there are some differences between which features are supported. For more information on the limitations with a specific 3D application, see:

• Importing objects from Maya
• Importing objects from Cinema 4D
• Importing objects from 3ds Max
• Importing objects from Cheetah3D
• Importing objects from Modo
• Importing objects from LightWave
• Importing objects from Blender
• SketchUp Settings

Importing objects from Maya

Unity imports Maya files (.mb and .ma) through the FBX format, supporting the following:

• All nodes with position, rotation and scale; pivot points and names are also imported
• Meshes with vertex colors, normals and up to 2 UV sets
• Materials with texture and diffuse color; multiple materials per mesh
• Animation
• Joints
• Blendshapes
• Lights and Cameras
• Visibilty
• Custom property animation

Tip: For information on how to export an FBX file from Maya, see Exporting from other applications.

Limitations

Unity does not support Maya’s Rotate Axis (pre-rotation).

Joint limitations include:

• Joint Orient (joint only post-rotation)
• Segment Scale Compensate (joint only option)

Unity imports and supports any Rotate Order you specify in Maya; however, once imported, you cannot change that order again inside Unity. If you import a Model that uses a different rotation order from Unity’s, Unity displays that rotation order in the Inspector beside the Rotation property.

Tips and troubleshooting

• Keep your scene simple: only export the objects you need in Unity when exporting.
• Unity only supports polygons, so convert any patches or NURBS surfaces into polygons before exporting; see Maya documentation for instructions.
• If your model did not export correctly, the node history in Maya might be causing a problem. In Maya, select Edit > Delete by Type > Non-Deformer History and then re-export the model.
• The Maya FBX Exporter bakes un-supported complex animations constraints, such as Set Driven Keys, in order to import the animation into Unity properly. If you are using Set Driven Keys in Maya, make sure to set keys on your drivers in order for the animation to be baked properly. For more information, see the Maya documentation on Keyframe Animation.
• In Maya, the visibility value is present on each shape but can’t be animated and is not exported to the FBX file. Always set the visibility value on a node and not on a shape.

Importing objects from Cinema 4D

Unity imports Cinema 4D files (.c4d) through the FBX format, supporting the following:

• All objects with position, rotation and scale; pivot points and names are also imported
• Meshes with UVs and normals
• Materials with texture and diffuse color; multiple materials per mesh
• Animations FK (IK needs to be baked manually)
• Bone-based animations

Tip: For information on how to export an FBX file from Cinema 4D, see Exporting from other applications.

Limitations

Unity does not import Cinema 4D’s Point Level Animations (PLA). Use bone-based animations instead.

Cinema 4D does not export visibility inheritance. Set the Renderer to ‘Default’ or ‘Off’ in Cinema 4D to avoid any difference in the visibility animation between Cinema4D and Unity.

Importing Objects From 3ds Max

Unity imports 3ds Max files (.max) through the FBX format, supporting the following:

• All nodes with position, rotation and scale; pivot points and names are also imported
• Meshes with vertex colors, normals and one or more UV sets
• Materials with diffuse texture and color. Multiple materials per mesh
• Animations
• Bone-based animations
• Morphing (Blendshapes)
• Visibility

Note: Saving a 3ds Max file (.max) or exporting a generic 3D file type (.fbx) each has advantages and disadvantages see class-Mesh.

Tip: For information on how to export an FBX file from 3ds Max, see Exporting from other applications.

Importing objects from Cheetah3D

Unity imports Cheetah3D files (.jas) through the FBX format, supporting the following:

• All nodes with position, rotation and scale; pivot points and names are also imported
• Meshes with vertices, polygons, triangles, UVs, and normals
• Animations
• Materials with diffuse color and textures

Tip: For information on how to export an FBX file from Cheetah3D, see Exporting from other applications.

Importing objects from Modo

Unity imports Modo files (.lxo) through the FBX format, supporting the following:

• All nodes with position, rotation and scale; pivot points and names are also imported
• Meshes with vertices, normals and UVs.
• Materials with Texture and diffuse color; multiple Materials per mesh
• Animations

To get started, save your .lxo file in your Project’s Assets folder. In Unity, the file appears in the Project View.

Unity re-imports the Asset when it detects a change in the .lxo file.

Tip: For information on how to export an FBX file from Modo, see Exporting from other applications.

Importing objects from Lightwave

Unity imports Lightwave files through the FBX format, supporting the following:

• All nodes with position, rotation and scale; pivot points and names are also imported
• Meshes with up to 2 UV channels
• Normals
• Materials with Texture and diffuse color; multiple materials per mesh
• Animations
• Bone-based animations

You can also configure the Lightwave AppLink plug-in which automatically saves the FBX export settings you use the first time you import your Lightwave scene file into Unity. For more information, see the Lightwave Unity Interchange documentation.

Tip: For information on how to export an FBX file from Lightwave file, see Exporting from other applications.

Limitations

Bake your Lightwave-specific materials as textures so that Unity can read them. For information on doing this using a non-destructive pipeline, see Node system in Lightwave.

Unity does not support splines or patches. Convert all splines and patches to polygons before saving and exporting to Unity. For more information, see Lightwave documentation.

Importing objects from Blender

Unity imports Blender (.blend) files through the FBX format, supporting the following:

• All nodes with position, rotation and scale; pivot points and names are also imported
• Meshes with vertices, polygons, triangles, UVs, and normals
• Bones
• Skinned Meshes
• Animations

For information on how to optimize importing your Blender file into Unity, see Exporting from other applications.

Limitations

Textures and diffuse color are not assigned automatically. You can manually assign them by dragging the texture onto the mesh in the Scene View in Unity.

Blender does not export the visibility value inside animations in the FBX file.

• 2018–04–25 Page amended with limited editorial review