Interchange Import Reference

Names the imported asset similar to the source name when it meets the following criteria:

• This option is set to true.
• The Asset Name field is blank.
• Only one source.
• Only one asset.

Names the imported asset using this string when you meet the following criteria:

• Only one source.
• Only one asset.

Converts the imported meshes to the specified type.

The dropdown menu contains the following options:

• None (default)
• Static Mesh
• Skeletal Mesh

Specifies how vertex colors are handled on import.

The dropdown menu contains the following options:

• Replace: Uses the vertex colors from the imported source.
• Ignore: Ignores any vertex colors from the imported source. If reimporting, keeps existing mesh vertex colors.
• Override: Overrides all vertex colors with the specified color.

Defines how normals, tangents, and UVs are handled during the import process.

This menu contains the following options:

• Recompute Normals: Ignores and recomputes normals for an imported mesh.
• Recompute Tangents: Ignores and recomputes tangents for an imported mesh.
• Use MikkTSpace: Recomputes tangents using the MikkTSpace standard.
• Compute Weighted Normals: Uses the ratio between the surface area and the corner angle of triangles to compute normals.
• Use High Precision Tangent Basis: Stores tangents with 16 bit precision or 8 bit precision.
• Use Full Precision UVs: Stores UVs with floating point precision.
• Use Backwards Compatible F16Trunc UVs: Forces use of backwards-compatible F16 conversion with truncation for legacy meshes.
• Remove Degenerates: Removes degenerate triangles from imported meshes.

Defines which LOD Group imported static meshes are assigned to.

The dropdown menu contains the following options:

• Deco
• Foliage
• High Detail
• Large Prop
• Level Architecture
• None
• Small Prop
• Vista

Defines how custom collision meshes are handled during import.

This menu contains the following options:

• Import Collision: Imports custom collision. If no custom collision is present, one will be created.
• Import Collision According to Mesh Name: Imports meshes with specific prefixes as collision meshes. Supports the following prefixes:
  • UBX_: Box Collision
  • UCP_: Capsule Collision
  • USP_: Sphere Collision
  • UCX_: Convex Collision
• One Convex Hull Per UCX: Imports convex collision as a single hull. If false, Unreal Engine breaks down the collision and creates a hull for each piece.

Defines how Nanite, lightmaps, and distance fields are handled during the import process.

This menu contains the following options:

• Build Nanite: Toggles Nanite rendering at runtime for imported meshes.
• Build Reverse Index Buffer: Builds a reverse index buffer for imported static meshes.
• Generate Lightmap UVs: Generates lightmap UVS for imported static meshes.
• Two-Sided Distance Field Generation: Generates the distance field while treating every triangle as a front face. This prevents the distance field from being discarded due to the mesh being open, but lowers distance field ambient occlusion quality.
• Enable Physical Material Mask: Toggles a physical material mask for imported meshes.
• Min Lightmap Resolution: Defines the default texture resolution for the baked light and shadow texture generated by Lightmass. For more information, see Understanding Lightmapping in Unreal Engine.
• Source Lightmap Index: Defines the source UV channel to use when generating lightmaps.
• Destination Lightmap Index: Defines the UV channel index where the newly generated lightmap is stored.
• Build Scale: Defines the local scale applied when building the imported meshes.
• Distance Field Resolution Scale: Defines the scale value applied to distance fields volume textures for imported meshes. The default value is 1.0 and assumes the mesh has not been scaled in the world.
• Distance Field Replacement Mesh: Defines the static mesh to use when calculating ambient occlusion and shadowing using distance fields. When undefined, LOD 0 of the imported mesh is used.
• Max Lumen Mesh Cards: Defines the max number of Lumen mesh cards generated for that mesh.

Defines whether the import process of skeletal mesh assets is partial or total.

The dropdown menu contains the following options:

• Geometry and Skinning Weights: Imports all skeletal mesh content.
• Geometry Only: Imports only the skeletal mesh geometry.
• Skinning Weights Only: Imports only the skeletal mesh skin weights.

Defines how skin weights, animation thresholds, and morph targets are handled during the import process.

This menu contains the following options:

• Use High Precision Skin Weights: Uses 16 bit precision for skin weights instead of 8 bit.
• Threshold Position: Defines the distance threshold to use when determining if two vertex positions are equal.
• Threshold Tangent Normal: Defines the distance threshold to use when determining if two normals, tangents, or binormals are equal.
• Threshold UV: Defines the distance threshold to use when determining if two UVs are equal.
• Morph Threshold Position: Defines the distance threshold to use when determining vertex position equality when computing morph target changes.
• Bone Influence Limit: Defines the maximum number of bone influences each vertex in the imported mesh can use. If set higher than the value in the Project Settings, this has no effect. If set to 0, the import uses the value of Default Bone Influence Limit set in the Project Settings.

Defines which animation time range to import.

The dropdown menu contains the following options:

• Source Timeline: Imports the range of frames based on the timeline definitions found in the source.
• Animation Time: Imports the range of frames that contain animation.
• Set Range: Imports the range of frames defined by the Frame Import Range.

Defines what is created when a material asset is imported.

The dropdown menu contains the following options:

• Import as Material: Imports material assets from the source as separate materials.
• Import as Material Instance: Imports material assets from the source as material instances.

Defines the parent material to use when importing materials as a material instance. If you select None, one will automatically be chosen during the import process.

Unreal Engine chooses from the following shader models:

• Lambert and Phong: PhongSurfaceMaterial
• Unlit: UnlitMaterial
• Metallic/Roughness PBR:
  • ClearCoatMaterial_MR
  • PBRSurfaceMaterial_MR
  • SheenMaterial_MR
  • ThinTranslucentMaterial_MR
• Specular/Glossiness PBR:
  • PBRSurfaceMaterial_SG
  • ClearCoatMaterial_SG
  • SheenMaterial_SG
  • SubsurfaceMaterial_SG
  • ThinTranslucentMaterial_SG

Defines how compression and texture size are handled during the import process.

This menu contains the following options:

• Prefer Compressed Source Data: Tells the translator to provide compressed source data when possible.This results in smaller asset file sizes but some operations might be slower.
• Allow Non Power of Two: Defines whether textures with a non-power of two resolution are imported.