PredictionRigidbody

This class provides accurate simulations and re-simulations when applying outside forces, most commonly through collisions.

Using PredictionRigidbody is very straight forward. In short, you move from applying force changes to the rigidbody onto the PredictionRigidbody instance instead.

View the Creating Code guide for using PredictionRigidbody in your replicate and reconcile methods.

Using Outside The Script

As mentioned above you should always apply forces to the PredictionRigidbody component rather than the Rigidbody directly. Our first guides demonstrate how to do this within the replicate method, as well how to reconcile using the PredictionRigidbody, but do not show how to add forces from outside scripts, such as a bumper in your game.

There is virtually no complexity to adding outside forces other than remembering to add them again, to the PredictionRigidbody and not the Rigidbody.

The example below is what it might look like if using a trigger on a world object to repel the player.

For triggers and collisions to work properly with prediction you must use our NetworkTrigger/NetworkCollision components. Otherwise, due to a Unity limitation, such interactions would not work. You can learn more about those components here.

Fun fact: Fish-Networking is the only framework that has the ability to simulate Enter/Exit events with prediction; not even Fusion does this!

private void NetworkTrigger_OnEnter(Collider other)
{
    //Add upward impulse when hitting this trigger.
    if (other.TryGetComponent<RigidbodyPlayer>(out rbPlayer))
        rbPlayer.PredictionRigidbody.AddForce(Vector3.up, ForceMode.Impulse);
    //Do not call Simulate on the PredictionRigidbody here. That should only be done
    //within the replicate method.
}

There is a fair chance a number of controllers will want to set velocities directly as well. PredictionRigidbody does support this. We encourage you to review the PredictionRigidbody API for all available functionality.

Our last example demonstrates setting velocities directly.

You would still call PredictionRigidbody.Simulate() regardless of how velocities are set.

float horizontal = data.Horizontal;
Vector3 velocity = new Vector3(data.Horizontal, 0f, 0f) * _moveRate;
PredictionRigidbody.Velocity(velocity);

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