A general overview of some of the tools and workflows used and applied by the Unity Team for the creation of their state of the art Digital Human, Gawain.
They used two different rig hierarchies. One for the body the other for the head.
Classical full body game rig. Skin weights up to the torso. Corrective blendshapes for the hands and the back.
Combination of Joint hierarchy and over 200 Blendshapes.
Non-deforming body parts like the gum don't have an optimized topology.
All the hair consists of cards. Hair is exported as a separated object and is not part of the head mesh. It's attachment to the deforming mesh happens in Unity.
The Unity Team developed a set of very useful tools to attach elements to a deforming mesh in realtime. You can implement those tools in your own project by getting them here.
First an empty dataset is created in the Assets Window. (right click → Digital Human → skin attachment data )
Then in the outliner you select the object you want to have attached to the deforming mesh. Add a 'Skin Attachment Target'-Script to it's Inspector and specify the dataset you just added.
Select the mesh driving the deformation, add a 'Skin Attachment'-Script to its inspector and specify the targets. (This only works if you insert the script after the 'Skinned Mesh Renderer'/'Mesh Renderer' )
Go back to the inspector of the target and fill in the dataset with the required mesh information.
As for now these tools only work with meshes being deformed by the GPU.
The skin and eyes are using a dedicated shader connected to a set of dedicated scripts.
The eyes can easily be customized to fit the needs of the required reference model.
We're still looking into the skin shader, particularly the system they applied to blend 82 different textures based on the faceshape.
For further insight into this project, please refer to these links: