Soft-Body Jelly
A soft body is a mesh of point masses joined by springs. Each spring pulls its two masses back toward a rest length with a stiffness you control, damping bleeds off energy so the wobble settles, and a ring of pressure keeps blobs from collapsing. Gravity pulls everything down onto the floor and walls, where collisions squash the shape and it springs back. Drag any blob with the mouse to stretch and throw it, add more blobs, and tune stiffness, damping and gravity to go from stiff rubber to loose slime. The whole simulation uses Verlet integration on a canvas, entirely in your browser.
Runs 100% in your browser — simulations are computed locally on your device.
Read the full guide to this tool
Notes
- Every edge is a damped spring obeying Hooke’s law, F = -k x: higher stiffness k snaps the shape back fast and feels rigid, lower k lets it wobble and sag like jelly.
- Verlet integration updates positions from the previous two positions instead of storing velocity, which keeps the springy network stable even when many constraints tug on the same mass.
- Internal pressure and a shell of edge springs together stop the blob from folding flat, so it behaves like a closed balloon of fluid rather than a loose net of points.
- Runs 100% in your browser — simulations are computed locally on your device.
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