FBX Import Options Reference

Skeletal Mesh

For Static Meshes: This will attempt to import the FBX file as a Skeletal Mesh. The import options will switch to handle importing the FBX file as a Skeletal Mesh.

Auto Generate Collision

This will automatically generate collision for your Static Mesh. This will not be used if custom collision is detected in the FBX file.

Static Mesh LODGroup

This dropdown allows you to choose the LOD group to which the mesh will be assigned. Mesh LOD groups define default level-of-detail settings, light map resolution, and permit global overrides (e.g. reduce all SmallProp LODs by 10%). Mesh LOD group settings may be overridden per-platform / device profile. You may select an LOD group at import time and change it at any time in the Static Mesh Editor .

Vertex Color Import Option

If enabled, vertex colors on an existing mesh are replaced with the vertex colors from the FBX file. Disable this to preserve vertex colors painted within the editor using the Mesh Paint tool.

Vertex Override Color

This will be override color in the case that Vertex Color Import Option is set to Override.

Remove Degenerates

If enabled, degenerate triangles found during import will be removed. Disabling this option will keep degenerate triangles found. In general, this option should be enabled.

Build Adjacency Buffer

If true , the mesh will be optimized for PN tessellation. It is recommended to disable for larger meshes.

Build Reveresed Index Buffer

This is used to reduce the number of GPU state changes between drawcalls. This is required to optimize a mesh in mirrored transform. It will also double the index buffer size.

Generate Lightmap UVs

If enabled, the importer will generate a set of unique, non-overlapping, UVs for use with static lighting.

One Convex Hull per UCX

This option forces all UCX meshes to receive one convex hull. If disabled, then a UCX mesh could be decomposed by the engine into a series of convex hulls to get the appropriate shape.

Transform Vertex to Absolute

If true , the FBX file will use the transform, offset, and pivot for the world origin. If false , the FBX will import without any node heirarchy transform.

Bake Pivot in Vertex

If true , the pivot rotation will be applied to the mesh. The pivot of the FBX file will then be the origin of the mesh. Transform Vertex to Absolute must be set to false .

Import Mesh LODs

Creates LOD models for Unreal meshes from LODs defined in the file. Otherwise, only the base mesh from the LOD group is imported. For Skeletal Meshes, the LOD models can be skinned to the same skeleton, or a different skeleton. If the LOD model is skinned to a different skeleton, it must meet the Unreal LOD requirements, with the exception that the name of the root bones can be different since the FBX importer renames the root bones automatically.

Normal Import Method

This import option adjusts how Normals will be handled. The options are as follows:

Normal Generation Method

The option to choose between MikkTSpace or Built-in Normal generation method.

Skeletal Mesh

For Skeletal Meshes, disabling this will have the importer attempt to import the FBX file as a Static Mesh.

Import Mesh

Whether to import the mesh. This allows animation only imports when importing a Skeletal Mesh.

Import Content Type

Mesh content type you are importing.

Skeleton

The Skeleton the SkeletalMesh should target. If no existing Skeleton is selected, a new one will be created from the SkeletalMesh being imported. The new Skeleton's name will be that of the SkeletalMesh with Skeleton appended.

Vertex Color Import Options

If enabled, vertex colors on an existing mesh are replaced with the vertex colors from the FBX file. Disable this to preserve vertex colors painted within the editor using the Mesh Paint tool.

Vertex Override Color

This will be override color in the case that Vertex Color Import Option is set to Override.

Update Skeleton Reference Pose

If enabled, this will update the Reference Pose of Skeleton Asset of the Skeletal Mesh/Animation being imported, to the reference pose in the FBX file being imported.

Use T0As Ref Pose

If enabled, the first frame (frame 0) of the animation track will be used to replace the Skeletal Mesh's reference pose.

Preserve Smoothing Group

If enabled, triangles with non-matching smoothing groups will be physically split, duplicating shared vertices.

Import Meshes in Bone Hierarchy

If enabled, meshes nested in bone hierarchies will be imported instead of being converted to bones.

Import Morph Targets

If enabled, MorphTargets will be imported from the FBX files along with the SkeletalMesh.

Import Mesh LODs

If enabled, creates LOD models for Unreal meshes from LODs defined in the file. Otherwise, only the base mesh from the LOD group is imported. For skeletal meshes, the LOD models can be skinned to the same skeleton, or a different skeleton. If the LOD model is skinned to a different skeleton, it must meet the Unreal LOD requirements, with the exception that the name of the root bones can be different since the FBX importer renames the root bones automatically.

Normal Import Method

Allows for control of how Normals will be handled. The options are as follows:

Normal Generation Method

The option to choose between MikkTSpace or Built-in Normal generation method.

Create PhysicsAsset

If enabled, this will generate a new PhysicsAsset for the imported Skeletal Mesh. The PhysicsAsset will be composed of mostly spheres (with the exception being the root which will be a capsule/SphrL object), with the constraints being completely free on all rotational axis and completely locked on positional axis.

Select PhysicsAsset

If Create PhysicsAsset is disabled, you will be able to choose a PhysicsAsset that already exists or none to simply not have the Skeletal Mesh associated with a PhysicsAsset.

Skeleton

The Skeleton the SkeletalMesh should target. If no existing Skeleton is selected, a new one will be created from the SkeletalMesh being imported. The new Skeleton's name will be that of the SkeletalMesh with Skeleton appended.

Import Animations

If enabled, Animations will be imported from the FBX files along with the SkeletalMesh. A name for the Animation can be entered in the text box to override the default naming.

Animation Length

Import Meshes in Bone Hierarchy

If checked, the meshes nested in bone hierarchies will be imported instead of being converted to bones.

Frame Import Range

Use Default Sample Rate

If true , the default sample rate of 30 frames-per-second is used for the animation. If unchecked, the system determines the sample rate from the FBX file.

Custom Sample Rate

Sample FBX animation data at the specified sample rate. When set to 0, the best sample rate is automatically determined.

Import Custom Attribute

If enabled, import a custom attribute as a curve within the animation. Requires Import Animations to be enabled.

Delete Existing Custom Attribute Curves

If true, all previous custom attribute curves will be deleted when doing a reimport.

Import Bone Track

Import bone transform tracks. If false, this will discard any bone transform tracks. (Useful for curves-only animations.)

Set Material Curve Type

If true , this will set the Material Curve Type for all custom attributes that exists.

Material Curve Suffixes

Specify the suffix for Material Curve Types using the custom attribute. This does not matter if Set Material Curve Type is set to true .

Remove Redundant Keys

Redundant keys will be removed when importing a custom attribute as a curve.

Delete Existing Morph Target Curves

If enabled, this deletes currently existing MorphTargets. This setting is only used when reimporting a mesh and can be set in the Skeletal Mesh Editors Reimport settings tab.

Do not import curves with 0 values

When importing a custom attribute or morph target as a curve, do not import if it doesn't have any value other than zero. This is to avoid adding extra curves to evaluate.

Preserve Local Transform

The way the engine calculates and accumulates transforms is different. We calculate the global transform and then calculate back to the local transform. In some cases, this can affect animations using 3DS Max or non-uniform scale.

Override Animation Name

The name to assign the animation. If nothing is entered here, the Naming Rules will be used. Requires Import Animations to be enabled.

Import Translation

This will enable the mesh to be moved along the XYZ axis when imported. This will be the location of the mesh when imported offset from the world origin.

Import Rotation

This will enable the mesh to be rotated along the XYZ axis when imported.

Import Uniform Scale

This will enable the mesh to be scaled uniformly when imported.

Convert Scene

This will convert the scene from the FBX coordinate system to use UE4's coordinate system.

Force Front XAxis

This will convert the scene from the FBX coordinate system to UE4's coordinate system with the front X axis instead of -Y axis.

Convert Scene Unit

This will convert the scene from the FBX units of measurement to UE4's unit of measure, centimeters.

Override Full Name

This will use the string "Name" field as the full name of the mesh. This option only works when the scene contains one mesh.

Search Location

Specify where we should search for matching materials when importing:

Material Import Method

Specify the import method for the following options.

Import Textures

If enabled, Textures referenced in the FBX file are imported into Unreal. If Import Materials is true , textures are always imported regardless of this setting.

Invert Normal Maps

If enabled and textures are being imported, normal maps values will be inverted.

Reorder Material to Fbx Order

If enabled, the material list will be reordered to the same order as the FBX file.

StaticMesh

If Override FullName is:

• Enabled

  • If single mesh in file - Named as %1

  • If multiple meshes in file and Combine Meshes is:

    • Enabled - Named as %1

    • Disabled - Named as %1_%2

• Disabled

  • If single mesh in file - Named as %1_%2

  • If multiple meshes in file and Combine Meshes is:

    • Enabled - Named as %1

    • Disabled - Named as %1_%2

SkeletalMesh

If Override FullName is:

• Enabled

  • If single mesh in file - Named as %1

  • If multiple meshes in file - Named as %1_%2

• Disabled - Named as %1_%2

AnimationSequence

If importing Animation with SkeletalMesh:

• If animation name is entered (considered %1 in this case):

  • If single sequences in file - Named as %1

  • If multiple sequences in file - Named as %1_%2

• If no name entered - Named as %1_%2

If importing only Animation:

• If single sequences in file - Named as %1

• If multiple sequences in file - Named as %1_%2

MorphTarget

Uses the names of the MorphTarget nodes in the FBX file.