Step-by-Step Guide

Open the plugin window (Tools > MetaHuman > MetaHuman Optimizer) and switch to the Groom Bindings tab.

Placeholder: image of the Groom Bindings tab.

1. Add groom source folders

Click the folder picker and select one or more Content Browser folders that contain your groom assets. The tool scans each folder recursively, so you can point it at a top-level grooms directory and it will find everything inside automatically.

Only groom assets whose names start with Hair, Eyebrow, Eyelash, Beard, or Mustache are processed. All other assets in the folder are silently skipped.

2. Set a source mesh (optional)

The Source Mesh picker lets you specify a skeletal mesh to use as the projection reference for every binding in the batch. This field is optional. What you set here determines how the tool computes the binding:

If your target meshes were created with the Face Optimizer and have not been positionally translated, leave this field empty and leave the offset values at zero. That is the most common case.

3. Add target face meshes

Click the target mesh picker and select the optimized skeletal mesh assets you want to bind grooms to. You can add multiple meshes in one batch. The tool extracts each character name from the asset name (expected format: SKM_CharName_Optimized) and uses it for output folder naming and binding asset naming.

4. Configure binding settings

Set the output folder, quality options, and any advanced overrides:

• Output Folder: the Content Browser path where all binding assets are saved. Bindings are organized into per-character and per-groom-type subfolders automatically.
• Face Material Slot: the material element index (0-based) of the face skin geometry on your target mesh. Default is 0.
• RBF Quality: interpolation accuracy for strand root projection (0-100). 100 is recommended for final bindings.
• Source Mesh LOD / Target Mesh Min LOD: LOD settings for projection and runtime coverage. Defaults of 0 cover all cases.
• Overwrite Existing: when enabled, existing binding assets at the output path are deleted and recreated. Disabled by default (skips existing bindings).
• Offset X / Y / Z: only relevant when Source Mesh is empty and your target meshes have been positionally translated. Enter the translation your meshes were shifted by and the tool applies the inverse to the auto-generated origin mesh. See The Offset Mode below.

5. Click "Bind Grooms"

The tool processes every combination of target mesh and groom asset in one pass. A progress indicator shows the current binding number out of the total (for example, "4/20: Sophia"). The operation is synchronous. When it finishes, a summary shows how many bindings were created, skipped, or failed.

Output Structure

For a batch with 2 characters and 3 grooms, the output looks like this:

/Game/MetaHumans/Optimized/GroomBindings/
    00-Origin/                        <- auto-generated origin meshes (auto offset mode only)
        SKM_Sophia_Origin
        SKM_Ada_Origin
    Sophia/
        Hair/
            GB_Sophia_GR_Hair_Long
            GB_Sophia_GR_Hair_Short
        Eyebrows/
            GB_Sophia_GR_Eyebrows_Thick
    Ada/
        Hair/
            GB_Ada_GR_Hair_Long
            GB_Ada_GR_Hair_Short
        Eyebrows/
            GB_Ada_GR_Eyebrows_Thick

The 00-Origin folder only appears when using auto offset mode. Origin meshes are reused across runs and are only created once per character.

Verifying the Result

Placeholder: how to open a binding asset in the Content Browser to preview projection quality in the Groom Binding editor viewport. What good and bad projection looks like. How to assign a binding to a Groom Component in the character Blueprint.

The Offset Mode (Advanced)

This mode is only needed when a target mesh has been positionally translated from the space where its grooms were originally authored. This happens when you move the head in Blender to align it with a different body rig.

To use it, leave the Source Mesh field empty and enter the translation offset your mesh was shifted by in the Offset X / Y / Z fields. The tool will:

1. Duplicate each target mesh to create an origin mesh
2. Apply the inverse of your offset to the origin mesh vertices so its positions align with the original groom-authoring space
3. Use the origin mesh as the projection source for each binding

The origin meshes are saved to a 00-Origin subfolder inside the output root and reused on subsequent runs.