Built-in Components

Predicted Physics Callbacks

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PredictedPhysicsCallbacks gives any predicted object rollback-aware 3D collision and trigger events without needing a PredictedRigidbody. Use it on kinematic colliders, trigger volumes, and Character Controllers that still need to know what they touched on the simulated timeline.

It is a StatelessPredictedIdentity, so it carries no state of its own. Unity's collision messages are recorded during the tick, stored in the prediction event history, and raised again in the right order when the tick is replayed, exactly like the rigidbody events.

Setup

  1. Add a Collider (or Character Controller) to the GameObject.
  2. Add PredictedPhysicsCallbacks to the same GameObject.
  3. Enable Physics 3D under the Prediction Manager's Built In Systems and Unity Physics 3D in Physics Provider.

Use the Event Mask to pick which callbacks are recorded. Every kind is enabled by default on this component, including the Stay variants; trim it down to what you read.

PurrDiction: 1.4.0 and newer

Events

The struct events match the rigidbody components: onPredictedCollisionEnter, onPredictedCollisionExit, onPredictedCollisionStay, onPredictedTriggerEnter, onPredictedTriggerExit, and onPredictedTriggerStay. See Predicted Rigidbody for the payload structs and the otherId contract.

[SerializeField] private PredictedPhysicsCallbacks callbacks;

private void OnEnable()
{
    callbacks.onPredictedTriggerEnter += OnTriggerEntered;
}

private void OnDisable()
{
    callbacks.onPredictedTriggerEnter -= OnTriggerEntered;
}

private void OnTriggerEntered(PredictedTrigger trigger)
{
    // trigger.other and trigger.otherId identify who walked in
}

The GameObject-only onCollisionEnter, onTriggerEnter, and friends are still raised but marked obsolete, and they skip the Exit raised by a deletion since they have no GameObject to pass.

Character Controller hits

When the GameObject has a CharacterController, Unity's OnControllerColliderHit is recorded too. Enable Controller Collider Hit in the event mask and subscribe to onControllerColliderHit:

callbacks.onControllerColliderHit += (GameObject other, PhysicsControllerHit hit) =>
{
    // hit.point, hit.normal, hit.moveDirection, hit.moveLength
};

PhysicsControllerHit is a packed copy of the parts of ControllerColliderHit that matter for gameplay, so it survives rollback and replay. It is how a predicted character controller can push rigidbodies, detect walls, or stick to moving platforms on the simulated timeline.

PurrDiction: Older than 1.4.0

Events

The component exposes onCollisionEnter, onCollisionExit, onCollisionStay, onTriggerEnter, onTriggerExit, and onTriggerStay. Collision events include a PhysicsCollision; trigger events provide the other GameObject.

As with every predicted event, mutate predicted state inside the handler and keep one-shot presentation behind PredictedEvent or predictionManager.isVerifiedView.