allow rigidbodies to travel through portals

Assets/Escape Room Engine/Portal/PortalDriver.cs

@@ -8,6 +8,7 @@ namespace Escape_Room_Engine.Portal
     {
         /// <summary>
         /// The object that will be transported through the portal. Usually either this object or a parent offset object.
+        /// If left empty, it will default to this object.
         /// </summary>
         [SerializeField] private Transform traveller;
 
@@ -21,11 +22,19 @@ namespace Escape_Room_Engine.Portal
         /// </summary>
         public Collider Collider { get; private set; }
 
+        private Rigidbody _rigidbody;
+
         private void Awake()
         {
             // check whether the collider is set up correctly
             Collider = GetComponent<Collider>();
             if (Collider.isTrigger) throw new Exception("Collider must not be a trigger.");
+            
+            // check whether the traveller is set
+            if (!traveller) traveller = transform;
+            
+            // get the rigidbody if there is one
+            _rigidbody = GetComponent<Rigidbody>();
         }
 
         public void Teleport(Portal from, Portal to)
@@ -33,6 +42,11 @@ namespace Escape_Room_Engine.Portal
             var m = to.transform.localToWorldMatrix * Portal.HalfRotation * from.transform.worldToLocalMatrix *
                     traveller.localToWorldMatrix;
             traveller.transform.SetPositionAndRotation(m.GetPosition(), m.rotation);
+            if (_rigidbody)
+            {
+                _rigidbody.velocity = to.transform.TransformDirection(
+                    Portal.HalfRotation.rotation * from.transform.InverseTransformDirection(_rigidbody.velocity));
+            }
         }
     }
 }