Locked rotations

A character capsule should slide and fall, but never tip over. You get that by restricting the body’s degrees of freedom to translation only. Both capsules below take the same off-center shove: the orange one rotates freely and topples, the green one has its rotations locked and just slides.

Drag to orbit

❚❚ Pause ↺ Reset

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Orange: free to rotate (topples). Green: rotations locked (stays upright).

Want a real character controller?

An upright capsule is only the start — a game character also needs hover, ground/slope detection, jumping, and moving-platform support. jolt-ts-character-controller provides all of it on top of jolt-ts. See the Character & vehicle controllers guide.

How it works

The fluent builder has a lockRotations() shortcut:

const character = world.createBody(
  Body.dynamic()
    .shape(Shape.capsule({ halfHeight: 0.5, radius: 0.35 }))
    .translation(0, 0.85, 0)
    .layer("moving")
    .lockRotations(), // translation only — the capsule can't tip
);

lockRotations() is shorthand for allowing just the three translation axes. You can pick any subset explicitly:

world.createBody({
  type: "dynamic",
  shape: Shape.capsule({ halfHeight: 0.5, radius: 0.35 }),
  allowedDofs: ["translation-x", "translation-y", "translation-z"],
});

Related

• Bodies & motion — the full allowedDofs list.
• jolt-ts-character-controller — a ready-made imperative character (and vehicle) controller built on jolt-ts, if you want more than an upright capsule.