To bring changes made to the unbaked MetaHuman materials back into MetaHuman Creator, or to use entirely different materials on a MetaHuman, use the Override Materials feature.
You can assemble a MetaHuman without baking textures and materials. This gives you direct access to the full, unbaked material and all of its parameters. While unbaked assembly gives you more control over MetaHuman materials, there are situations where you may want to bring those changes back into MetaHuman Creator and reassemble the MetaHuman to still take advantage of material baking. To bring changes made to the unbaked MetaHuman materials back into MetaHuman Creator use the Override Materials feature.
Alternatively, you may want to make use of entirely different materials on a MetaHuman character using this feature.
If the overridden materials are child instances of the MetaHuman base materials, you can run the assembly process to produce optimized materials used in the Cine, High, Medium, and Low assembly options. Materials that are not child instances of the MetaHuman base materials cannot be baked.
Overriding with Material Instances
The texture and material baking system requires input materials that are compatible with the base materials used by the MetaHuman Creator plugin. The baking system expects certain outputs of each material instance used in the Character as they are used to produce the baked textures. If the overridden materials are child instances of the base materials, the assembly process bakes textures to the optimized material and texture set, if not, the same set of textures will be produced but they will use the output produced by the overridden materials.
The baking process will run the Texture Graphs in /MetaHumanCharacter/TextureGraphs. If the goal is to use a custom material for baking, ensure the outputs used in the Texture Graphs match what the final baked material expects.
Overriding with Custom Materials
You can also override the default MetaHuman material set with your own custom materials. In this case, the texture and material baking workflow does not execute during assembly, but the custom materials are applied to the MetaHuman character.
To override materials, navigate to the Texture and Material Overrides section in MetaHuman Creator and select which materials to override.
For example, if you want to create a MetaHuman with a stylized toon-shaded material, you can override the materials directly in MetaHuman Creator to verify the result before assembling.
