Fixing arrows not working properly in newer physics sims

Author: keithbradner

Assets/SteamVR/InteractionSystem/Longbow/Scripts/Arrow.cs

@@ -37,11 +37,29 @@ public class Arrow : MonoBehaviour
 
 		private GameObject scaleParentObject = null;
 
+		private float initialMass;
+		private float initialDrag;
+        private float initialAngularDrag;
+        private RigidbodyInterpolation initialInterpolation;
+        private CollisionDetectionMode initialCollisionDetection;
+        private bool initialUseGravity;
 
-		//-------------------------------------------------
-		void Start()
-		{
-			Physics.IgnoreCollision( shaftRB.GetComponent<Collider>(), Player.instance.headCollider );
+
+        private void Awake()
+        {
+            initialMass = shaftRB.mass;
+            initialDrag = shaftRB.drag;
+            initialAngularDrag = shaftRB.angularDrag;
+            initialInterpolation = shaftRB.interpolation;
+            initialCollisionDetection = shaftRB.collisionDetectionMode;
+            initialUseGravity = shaftRB.useGravity;
+            Destroy(this.GetComponent<Rigidbody>());
+        }
+
+        //-------------------------------------------------
+        void Start()
+        {
+            Physics.IgnoreCollision(this.GetComponent<Collider>(), Player.instance.headCollider);
 		}
 
 
@@ -52,17 +70,35 @@ void FixedUpdate()
 			{
 				prevPosition = transform.position;
 				prevRotation = transform.rotation;
-				prevVelocity = GetComponent<Rigidbody>().velocity;
+				prevVelocity = shaftRB.velocity;
 				prevHeadPosition = arrowHeadRB.transform.position;
 				travelledFrames++;
 			}
 		}
 
 
+		public void StartRelease()
+        {
+            Rigidbody rb = this.gameObject.AddComponent<Rigidbody>();
+            rb.isKinematic = true;
+            if (shaftRB == null)
+                shaftRB = rb;
+
+            shaftRB.mass = initialMass;
+            shaftRB.drag = initialDrag;
+            shaftRB.angularDrag = initialAngularDrag;
+			shaftRB.interpolation = initialInterpolation;
+			shaftRB.collisionDetectionMode = initialCollisionDetection;
+            shaftRB.useGravity = initialUseGravity;
+
+			arrowHeadRB.GetComponent<FixedJoint>().connectedBody = rb;
+        }
+
+
 		//-------------------------------------------------
 		public void ArrowReleased( float inputVelocity )
-		{
-			inFlight = true;
+        {
+            inFlight = true;
 			released = true;
 
 			airReleaseSound.Play();

Assets/SteamVR/InteractionSystem/Longbow/Scripts/ArrowHand.cs

@@ -229,7 +229,8 @@ private void FireArrow()
 			currentArrow.transform.parent = null;
 
 			Arrow arrow = currentArrow.GetComponent<Arrow>();
-			arrow.shaftRB.isKinematic = false;
+            arrow.StartRelease();
+            arrow.shaftRB.isKinematic = false;
 			arrow.shaftRB.useGravity = true;
 			arrow.shaftRB.transform.GetComponent<BoxCollider>().enabled = true;
 
@@ -240,6 +241,9 @@ private void FireArrow()
 			arrow.arrowHeadRB.AddForce( currentArrow.transform.forward * bow.GetArrowVelocity(), ForceMode.VelocityChange );
 			arrow.arrowHeadRB.AddTorque( currentArrow.transform.forward * 10 );
 
+			arrow.shaftRB.velocity = arrow.arrowHeadRB.velocity;
+			arrow.shaftRB.angularVelocity = arrow.arrowHeadRB.angularVelocity;
+
 			nocked = false;
             nockedWithType = GrabTypes.None;