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A familiar contract. A different world.

Ammo.js is the Bullet-derived sibling to the Rapier and Jolt studies. This route keeps the same scene-to-world contract visible while tracing Ammo's per-instance rigid bodies and fixed-rate synchronization loop.

Initializing Preparing renderer

Preparing WebGLRenderer, instanced buffers, and AmmoPhysics...

physics: -
boxes: -
spheres: -
bodies: -
resets: -
render frames: -
fps: -

Indexed body controlsAmmo transform sync

Drop interval 0.75s

auto-reset random instances wireframe instance meshes

Click a box or sphere to select its instance index. Ammo's reposition method clears linear and angular velocity before changing the body transform.

Ammo contractBullet/WASM bridge

await AmmoPhysics()load Ammo.js from a CDN

mesh.userData.physicsdeclare mass/restitution

physics.addScene(scene)register floor + instances

setMeshPosition(mesh, p, i)zero velocity + reposition

world.stepSimulation(delta, 10)advance the Bullet world

The current addon supports BoxGeometry, SphereGeometry, IcosahedronGeometry, ordinary meshes, and InstancedMesh. It exposes no official impulse, collider-helper, removal, or dispose method; the lifecycle limitation is intentionally visible.

Selected instancenone

source mesh-

instance index-

body shape-

reposition API-

Ammo is loading. The addon requires an active Internet connection and owns an internal fixed-rate timer.

Based on the official Ammo instancing example. Compare this route with the Rapier and Jolt labs: the public addon contract looks similar, but the underlying body ownership and lifecycle behavior differ.

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