private void ChangeBehaviour(AiBehaviour behaviour, float transitionTime)
{
if (_activeAi != null)
{
_activeAi.End();
}
// Stop movement prior to behaviour change, or else enemy will move towards its
// old movement direction during the wait period.
_motor.StopUntilResumed();
// Set new behaviour
_activeAi = GetBehaviour(behaviour);
_activeAi.Begin();
_activeBehaviour = behaviour;
// Simulate transition to new behaviour by waiting for a short time
Wait(transitionTime);
}