An acceleration-based jigglebone system with soft-body/squash-and-stretch physics for SkinnedMeshRenderers in Unity.

• GPU per-vertex deformations via shader, squash/stretch based on vertex color masks.

• Purely acceleration based, elevators don't cause things to float/sag.

• Works at all framerates with very little differences in the physics solve. (It's unhooked from a fixed timestep as well!)

• Can run on LateUpdate, FixedUpdate, and Update.

• Only runs when mesh is visible.

• Comes with a JiggleSurfaceApproximator which can keep a transform attached to the "skin" of a mesh. Great for censorbars and attachments that can't be added directly to the mesh.

This unity repository actually comes with a fully working project, with a working model in an example scene. If anything below doesn't make sense, download the project!

1. Use the included AmplifyShader node to add the vertex deformations to whatever shader you want. (URP, HDRP, Standard, whatever!).

2. Make sure your model has RGBA vertex-color masks for how bouncy parts of the model is, keep individual neighboring bouncing parts as different colors.

3. Set up a JiggleSoftbody with sensors overlapped in such a way that each "individual" bouncy part has its own sensor.

4. Add JiggleBones for the primary movement.

You can install Jiggle Physics with OpenUPM by checking out the badge above. Otherwise...

Simply add https://github.com/naelstrof/UnityJigglePhysics.git#upm as a package using the package manager.

Or if that doesn't work, add it to the manifest.json like so.

{
  "dependencies": {
    "com.naelstrof.jigglephysics": "https://github.com/naelstrof/UnityJigglePhysics.git#upm",
  }
}