Exporting from other applications

Unity supports FBX files which you can export from many 3D modeling applications. Use these guidelines to help ensure the best results:

1. Select what you want to export inside your 3D modeling application.
2. Prepare what you need to include inside your 3D modeling application.
3. Check the FBX settings before exporting.
4. Verify and import the FBX file into Unity.

Note: In addition to these generation guidelines about exporting from 3d modeling applications, some 3d modeling applications have more specific information under these sections:

• Maya
• Cinema 4D
• 3ds Max
• LightWave

Selecting what to export

Think about what you want to export: some scene objects are essential but others may be unnecessary. Applications often let you export selected objects or a whole scene. You can optimize the data in Unity by keeping only the essential objects.

If you choose to export only specific objects in your scene, you can:

• Export only the selected objects if your application supports it.
• Remove unwanted data from your scene and export the whole scene.
• Make a preset or a custom scene exporter to automate or simplify the selection export process.

Preparing what you need to include

Prepare your Assets for export, using the following considerations:

Setting the FBX export options

Check your FBX export settings:

• Check each setting in the export dialogue of your 3D modeling application so that you know what to match up the FBX import settings in Unity.
• Select whether to export Animation, Deformations, Skins, Morphs according to your needs.
• Nodes, markers and their transforms can be exported to Unity.
• Select any Cameras, Lights, and Visibility settings you want to import into Unity.
• Use the Latest Version of FBX where possible. Autodesk regularly updates their FBX installer.
• Make sure you use the same FBX version to import files into Unity as you used to export them from your 3D modeling application. Using different versions of the software can provide unexpected results.

Verifying and importing into Unity

Before importing your FBX file into Unity:

1. Verify the size of your exported file. Perform a sanity check on the file size (e.g. >10kb?).

2. Re-import your FBX file into a new scene back into the 3D modeling software you used to generate it. Check to make sure it is what you expected.

To import your file into Unity, follow the instructions for Importing, keeping in mind how you set the export options in your 3D modeling software.

Export settings in specific 3D modeling applications

Maya

You can use the FBX Export options to pick what to export in your FBX file.

Exporting BlendShapes (morphing)

When exporting BlendShapes (Morphing) from Maya, follow these guidelines:

• Apply the blend shape to the export mesh with its targets in order.
• If you require Maya animation keyframes, you can animate keyframes on the blend shape node.
• Enable the Animation > Deformed Models > Blend Shapes FBX Export option in Maya before exporting the mesh.
• If you also want to export skin deformation, enable the Animation > Deformed Models > Skins FBX Export option in Maya before exporting the mesh.

When you’ve imported the file into Unity, select it in the Project view and enable Bake Animations in the Animations tab of the Model Importer.

Cinema 4D

Animated characters using IK

If you are using IK to animate your characters in Cinema 4D, you have to bake the IK before exporting using the Plugins > Mocca > Cappucino menu in Cinema 4D. If you don’t bake your IK prior to importing into Unity, you only get animated locators and no animated bones.

Maximizing import speed

You can speed up file import into Unity by turning off the Embed Textures preference in Cinema 4D before you export. Check the Cinema 4D documentation for instructions.

3ds Max

Autodesk provides a Game Exporter Utility that targets the assets typically exported as game assets. You can also use the standard FBX Export utility to pick what to export in your FBX file.

For example, the default FBX exporter options (that basically exports everything) includes embedding Textures as image maps in the file. While this makes the file very portable, it also increases the file size.

In addition, when exporting from Maya, there are some extra considerations when dealing with the following:

• Exporting quads
• Bone-based Animations
• Morph targets (Blendshapes)
• UV sets for Lightmapping

Exporting quads

3dsMax’s editable Mesh always exports triangles. The editable poly retains quads and N-gons on import. So if you want to import quads into Unity, you have to use editable poly in 3ds Max.

Bone-based Animations

Follow these guidelines when you want to export bone-based animations in 3ds Max:

• After setting up the bone structure and the animations (using FK or IK), select all bones and/or IK solvers.
• Select Motion > Trajectories > Collapse. Unity makes a key filter, so the amount of keys you export is irrelevant.
• Click the Export button on the Game Exporter window or the OK button on the FBX Exporter window.
• Copy the FBX file into the Assets folder.
• Open Unity and reassign the Texture to the Material in the root bone.

When exporting a bone hierarchy with mesh and animations from 3ds Max to Unity, the GameObject hierarchy produced corresponds to the hierarchy you can see in the 3ds Max Schematic View. However, Unity uses a GameObject as the new root, containing the animations, and places the mesh and material information in the root bone.

If you prefer to keep animation and mesh information in the same Unity GameObject, parent the mesh node to a bone in the bone hierarchy in 3ds Max before exporting.

Morph targets (Blendshapes)

Follow these guidelines when you want to export Morph targets in 3ds Max:

• Apply the Morpher Modifier to the export mesh with appropriate morph targets set up in the Channel List.
• If you require 3ds Max animation keyframes, you can animate keyframes on the mesh/modifier.
• Enable the Animation > Deformed Models > Blend Shapes FBX Export option in 3ds Max before exporting the mesh.
• If you also want to export skin deformation, enable the Animation > Deformed Models > Skins FBX Export option in 3ds Max before exporting the mesh.

UV sets for Lightmapping

Unity has a built-in lightmapper, but you can also create lightmaps using texture baking (Render To Texture on the Rendering menu) feature and automatic unwrapping functionality in 3ds Max.

Usually one UV set is used for main texture and/or normal maps, and another UV set is used for the lightmap texture. For both UV sets to come through properly, the material in 3ds Max has to be Standard and both Diffuse (for main texture) and Self-Illumination (for lightmap) map slots have to be set up:

Note: If the object uses a Shell type of Material, Autodesk’s FBX exporter does not export UVs correctly.

Alternatively, you can use Multi/Sub Object material type and setup two sub-materials, using the main texture and the lightmap in their diffuse map slots, as shown below. However, if the faces in your Model use different sub-material IDs, this results in multiple materials being imported, which is not optimal for performance.

LightWave

You can access the FBX export settings window inside LightWave by selecting Save > Export > Export FBX from the File toolbar in LightWave Layout:

The Export FBX window appears.

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