Mesh to Metahuman

This document outlines the Mesh to MetahHuman workflow, for creating a MetaHuman from an existing Static or Skeletal Mesh.

Required Tools and Knowledge

To use the Mesh to MetaHuman feature, first familiarize yourself with the following concepts:

• Static Meshes and Skeletal Meshes in Unreal Engine

You need access to the following tools and programs:

• Unreal Engine 5 or newer
• MetaHuman Creator
• Quixel Bridge version 2022.0.2 or newer
• Microsoft Windows (currently unsupported on macOS and Linux).

This workflow is only supported in Unreal Engine 5 and newer versions.

Workflow

The Mesh to MetaHuman workflow consists of the following steps:

1. Set up your Unreal Engine project.
2. Import and prepare the character mesh.
3. Create and configure a MetaHuman Identity Asset.
4. Create and track a Neutral Pose.
5. Run the Identity Solve.
6. Submit the Template Mesh to the MetaHuman Backend.
7. Further customize your MetaHuman in MetaHuman Creator.
8. Download and import your MetaHuman into Unreal Engine 5.

These steps are covered in detail below.

Set Up Your Unreal Engine Project

To set up your project, complete the following steps:

1. Download the MetaHumans plugin from the Marketplace tab in the Epic Games Launcher. Install it to the engine, then enable the plugin in your project.If you need additional information on how to complete this step, refer to the Working with Plugins page in the Unreal Engine 5 documentation.
2. Open Quixel Bridge from the Main Toolbar, then sign in.This is a required step, even if you signed in to the Epic Games Launcher previously. Signing in to the Launcher does not sign you in to Quixel Bridge automatically.

Import and Prepare the Character Mesh

Next, you need to import your character mesh into Unreal Engine. The mesh can be a scan, a sculpt, or an existing game asset.

For best results, make sure that your mesh satisfies the following requirements:

• FBX or OBJ format.
• Has a texture or material. For best results, the mesh should be textured with the skin's albedo texture. Otherwise, it needs to have materials that separate the whites of the eyes (sclera) from the skin tone.
• The whites of the eyes (sclera) are showing. Your mesh doesn't need to have separate eye sockets and eyeballs, but it must have open eyes and visible separation between the eye and eyelid.Empty sockets are very likely to track poorly and generate fitting artifacts and other tracking imperfections.

If your mesh isn't textured with the skin's albedo texture, it needs to satisfy the following lighting requirements:

• Flat, front-facing lighting.
• Features are lit uniformly and symmetrically.
• Minimum contrast between significant facial features (nasolabial folds and lips).

Importing a mesh in FBX format can take significantly longer than importing an OBJ mesh. As a best practice, we recommend using an OBJ file if the mesh you are importing has over 200,000 vertices. This is a known limitation.

Import your mesh using one of the workflows described on the Importing Assets Directly page in the Unreal Engine 5 documentation, such as drag-and-drop.

In the Import Options window, expand the Mesh > Advanced section and enable the Combine Meshes option, if it is not already enabled.

After the import completes, double-click the resulting Static Mesh in the Content Browser to open it in the Static Mesh Editor.

You'll notice that the mesh doesn't have a texture.

To fix this, find the mesh's Material in the Content Browser and double-click it to open it in the Material Editor.

Drag the mesh's Texture from the Content Browser into the Material Editor, as shown in the screenshot below. This creates a new node for the Texture. Drag from the Texture node's RGB pin to the Material node's Base Color pin. This will replace the existing connection between the solid white Param node and the Material node. After you do this, delete the Param node.

Click the image for full size.

If the mesh isn't oriented correctly, adjust its Import Translation and / or Import Rotation properties in the Details panel (1), then click the Reimport Base Mesh button (2), as shown below.

Depending on the orientation of your imported mesh, you may need to enable the Force Front XAxis option in the same panel (3).

Click the image for full size.

You can disable the grid in the Mesh Editor from the Viewport Toolbar: click Show, then uncheck the Grid option, as shown below.

Click the image for full size.

If you see visual artifacts in the viewport, it is highly likely that the mesh won't track well. Most artifacts on scanned meshes come from vertex / tri splitting, usually because of multiple UV sets. To fix this, make sure your mesh only has the UV set necessary to map the albedo texture.

Once you are happy with the resulting mesh, save it, then close the Static Mesh Editor.

Create and Configure a MetaHuman Identity Asset

Next, you will create and configure a MetaHuman Identity Asset. This Asset holds the MetaHuman's face mesh (template mesh), body type information, and pose information.

Follow the steps below:

1. Right-click in the Content Browser. From the context menu, under Create Advanced Asset, select MetaHuman > MetaHuman Identity.The filename of the MetaHuman Identity Asset you create will be your MetaHuman's name in MetaHuman Creator.
2. Double-click the Asset you created to open it. Initially, this Asset will be empty.
3. In the main toolbar, click the Components from Mesh button. Then, search for and select the character mesh you imported.After you complete this step, the Components panel on the left side of the Metahuman Identity Asset Editor will be populated with the following Components:
   • Face
   • Template Mesh
   • Neutral Pose
   • Body
   Click the image for full size.
4. Select the Body Component and do the following:
   • Use the Height slider (1) to select whether your MetaHuman will be short, of average height, or tall.
   • Click a thumbnail (2) to choose the Body Type that will be used for your MetaHuman.
   Click the image for full size.You can adjust these values later in MetaHuman Creator.

Create and Track a Neutral Pose

Before the MetaHuman backend can create a MetaHuman-compatible Template Mesh from the mesh you uploaded, you need to create and track a Neutral Pose.

Changing the lighting in the viewport can make it easier to work with your mesh. You can switch between different lighting modes from the Viewport Toolbar, as shown below.

Click the image for full size.

For meshes that are textured with the skin's albedo texture, Unlit mode works best. For other meshes, you may have to choose Lit mode and rotate the light around until the entire face is lit evenly. To rotate the light, hold down the L key (or Ctrl + L keys, depending on how your engine is configured), then hold down the left mouse button and drag.

Continuing from the previous section, follow these steps:

1. In the Components panel, select the Neutral Pose Component.
2. Configure the Field of View from the Viewport menu (the menu looks like three horizontal lines and is located in the viewport toolbar). We recommend using a "long lens", which can be done by choosing a Field of View of 20 degrees or less.
3. In the Viewport, position the camera so that the mesh is facing forward and the head is completely visible.To navigate the viewport, hold down the right mouse button and use the WASD keys to move, and Q and E keys to pan the camera up and down.
4. With the Neutral Pose Component still selected, click Promote Frame (+) in the bottom toolbar.Click the image for full size.After you promote a frame, it will appear in the Frame Promotion Timeline, as shown below. As this is the first Promoted Frame, its name is Frame 0. Double-click the frame to rename it.Click the image for full size.If you need to manually fit details like ears or nostrils, you can repeat this process to promote additional frames (for example, a side profile view) and activate specific markers for those frames in the Markers Outliner. A frontal frame with full view of nasolabial folds, lips, and eyelids is always necessary. Additional frames should only contain Markers not present in the front frame, and be added only if a feature (e.g. ears or nostrils) fits poorly after the Identity Solve step.If you have multiple frames containing the same markers (for example, two different frontal frames), ensure only one of them is used for the Identity Solve. The Used to Solve boolean is a per-frame attribute that can be set in the details panel, or in the context menu that appears when right-clicking the frame in the timeline under the viewport.
5. With the frame you created still selected, in the main toolbar, click the Track Active Frame button. This creates a series of markers along the facial features of your mesh.Click the image for full size.If auto-tracking is enabled from the Promoted Frame's context menu, you will be able to move the camera around and see how well the tracker responds.
6. Lock the current frame. In the Frame Promotion Timeline, right-click the frame and make sure that the Lock Camera option is enabled.Once a frame is locked, you can still navigate by setting the camera in free roaming mode. To do this, click the Camera button on the left of the Frame Promotion Timeline.
7. (optional) Zoom in and tweak any markers that don't align correctly with facial features.

Run the Identity Solve

Still in the Identity Asset Editor, from the main toolbar, click the Identity Solve button. This button will only be enabled once at least one Promoted Frame exists in the timeline, and will produce good results only when the markers are active and well-tracked.

Identity Solve fits the Template Mesh vertices to the volume of the Neutral Pose mesh you tracked in previous steps.

Click the image for full size.

After the Identity Solve completes, you can toggle between your original mesh and the Template Mesh in the viewport by clicking the A / B tabs in the Viewport Toolbar. The A and B buttons activate two separate frame buffers for the same Viewport camera, and promoting a frame creates a snapshot of that camera. You can configure Viewport settings, such as lighting, individually for each of these two frame buffers.

In addition, you can toggle the display of both the original mesh and the Template Mesh in the same frame buffer from the viewport toolbar, by enabling or disabling the Neutral Pose and Template Mesh options, as shown below. Do this to see if your two meshes "z-fight" for screen occupancy.

Click the image for full size.

Submit the Template Mesh to the MetaHuman Backend

You can now submit the Template Mesh to the MetaHuman Backend to create your custom MetaHuman. In the MetaHuman Identity Asset Editor, click Mesh to MetaHuman.

Click the image for full size.

Wait for the process to complete before you move on to the next step.

Further Customize your MetaHuman in MetaHuman Creator

After the previous step completes, you can now access your MetaHuman in MetaHuman Creator.

For MetaHumans created through Mesh to MetaHuman, you will see an additional panel called Custom Mesh. Here, you can adjust the contribution of the Template Mesh's difference from a standard MetaHuman parametrization (the delta in volume between your input and a MetaHuman as it could otherwise be created in MetaHuman Creator alone):

• Click a region on the sample MetaHuman face in this panel, then move the slider to increase or decrease MetaHuman mesh influence.
• Use the Overall Influence slider to make global adjustments.

Both of the sliders above support symmetrical adjustments, as well as individual adjustments for the left and right side.

Initially, the MetaHuman will use the same texture as the Template Mesh in Unreal Engine for the skin, and the Blend, Sculpt, and Move editing modes will be unavailable. To unlock these modes, modes, click the Enable Editing button. You can choose to either edit your current MetaHuman, or make a duplicate.

The Mesh to MetaHuman process doesn't automatically match the MetaHuman's tone with the skin tone of the mesh. Use the Skin controls to choose a skin color for your MetaHuman.

This will override the Template Mesh texture.

The new skin texture may take 20-30 seconds to apply correctly. If the skin texture turns chalk white, keep moving the color picker every few seconds until it does. This is a known issue.

Download and Import your MetaHuman into Unreal Engine 5

Your new MetaHuman should now be available for download in Quixel Bridge. In Unreal Engine 5, open Bridge from the Main Toolbar.

Remember to sign in to Bridge with your Epic Games account, if you haven't done so already. Once you do, you'll be able to access your new MetaHuman in the My MetaHumans section of Bridge.

To download and export your MetaHuman, follow the guides below:

• Downloading and Exporting MetaHumans
• Exporting to Unreal Engine 5

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