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Constraints make motion legible.

This route turns Rapier's joint API into a controlled chain experiment: typed anchors, constrained degrees of freedom, motor and limit settings, contact policy, and explicit joint removal and re-attachment.

Initializing Preparing renderer

Preparing the chain, joint descriptors, and RapierPhysics...

physics: -
bodies: -
joints: -
type: -
motor: -
contacts: -
impulses: -
fps: -

Joint controlslink 1

joint descriptor

enable joint contacts show Rapier colliders

Select a link to inspect its body, parent joint, and anchor path.

Rapier joint contractofficial API boundary

await RapierPhysics()create gravity world

physics.addMesh(...)register rigid bodies

RAPIER.JointData.*(...)describe joint anchors

world.createImpulseJoint(...)connect two bodies

joint.configureMotorVelocity(...)drive a DOF

joint.setLimits(...)bound a DOF

world.removeImpulseJoint(...)detach constraint

new RapierHelper(world)inspect collider topology

Spherical, revolute, prismatic, rope, and spring descriptors all reuse the same six-body chain. The visible anchor markers are derived from the local anchor vectors passed into JointData.

Selected linkjoint 1

shape-

position-

parent joint-

joint state-

Rapier is loading. The helper becomes available only with a live Rapier world.

Based on the official Rapier joints example and joint API. The CPU fallback preserves the chain controls and labels, but it does not claim full constraint-solver parity.

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