feat(Controller): add methods to get touchpad axis and angle

It's now possible to get the current touchpad axis and angle via
method calls if this is required instead of using the events.

Assets/SteamVR_Unity_Toolkit/Scripts/VRTK_ControllerEvents.cs

@@ -217,20 +217,24 @@ public Vector3 GetAngularVelocity()
             return controllerAngularVelocity;
         }
 
+        public Vector2 GetTouchpadAxis()
+        {
+            return touchpadAxis;
+        }
+
+        public float GetTouchpadAxisAngle()
+        {
+            return CalculateTouchpadAxisAngle(touchpadAxis);
+        }
+
         private ControllerInteractionEventArgs SetButtonEvent(ref bool buttonBool, bool value, float buttonPressure)
         {
             buttonBool = value;
             ControllerInteractionEventArgs e;
             e.controllerIndex = controllerIndex;
             e.buttonPressure = buttonPressure;
             e.touchpadAxis = device.GetAxis();
-
-            float angle = Mathf.Atan2(e.touchpadAxis.y, e.touchpadAxis.x) * Mathf.Rad2Deg;
-            angle = 90.0f - angle;
-            if (angle < 0)
-                angle += 360.0f;
-
-            e.touchpadAngle = angle;
+            e.touchpadAngle = CalculateTouchpadAxisAngle(e.touchpadAxis);
 
             return e;
         }
@@ -246,6 +250,17 @@ private void Start()
             device = SteamVR_Controller.Input((int)controllerIndex);
         }
 
+        private float CalculateTouchpadAxisAngle(Vector2 axis)
+        {
+            float angle = Mathf.Atan2(axis.y, axis.x) * Mathf.Rad2Deg;
+            angle = 90.0f - angle;
+            if (angle < 0)
+            {
+                angle += 360.0f;
+            }
+            return angle;
+        }
+
         private void EmitAlias(ButtonAlias type, bool touchDown, float buttonPressure, ref bool buttonBool)
         {
             if (pointerToggleButton == type)