--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/Orchestland/Assets/LeapMotion/DemoResources/Scripts/FloatingStem.cs	Fri Jul 17 23:09:20 2015 +0900
@@ -0,0 +1,55 @@
+/******************************************************************************\
+* Copyright (C) Leap Motion, Inc. 2011-2014.                                   *
+* Leap Motion proprietary. Licensed under Apache 2.0                           *
+* Available at http://www.apache.org/licenses/LICENSE-2.0.html                 *
+\******************************************************************************/
+
+using UnityEngine;
+using System.Collections;
+
+public class FloatingStem : MonoBehaviour {
+
+  public float waterHeight = 0.0f;
+  public float transitionWidth = 0.2f;
+  public float waterForce = 0.1f;
+  public float waterTorque = 0.002f;
+  public float waterDrag = 5.0f;
+  public float waterAngularDrag = 10.0f;
+
+  public Vector3 waterCurrentVelocity;
+  public float waterCurrentForce = 0.1f;
+
+  private float air_drag_;
+  private float air_angular_drag_;
+
+  void Start() {
+    air_drag_ = GetComponent<Rigidbody>().drag;
+    air_angular_drag_ = GetComponent<Rigidbody>().angularDrag;
+  }
+
+  void FixedUpdate() {
+    float distanceFromSurface = transform.position.y - waterHeight;
+    if (distanceFromSurface >= 0) {
+      GetComponent<Rigidbody>().drag = air_drag_;
+      GetComponent<Rigidbody>().angularDrag = air_angular_drag_;
+      return;
+    }
+
+    GetComponent<Rigidbody>().drag = waterDrag;
+    GetComponent<Rigidbody>().angularDrag = waterAngularDrag;
+
+    float transition = Mathf.Clamp(-distanceFromSurface / transitionWidth, 0, 1);
+    GetComponent<Rigidbody>().AddForce(new Vector3(0, waterForce * transition, 0));
+
+    /*
+    float dot = Vector3.Dot(transform.up, Vector3.up);
+    Vector3 torque_vector = -dot * Vector3.Cross(transform.up, Vector3.up);
+    rigidbody.AddTorque((1 - transition) * waterTorque * torque_vector);
+    */
+
+    // Current.
+    Vector3 delta_current = waterCurrentVelocity - GetComponent<Rigidbody>().velocity;
+    delta_current.y = 0;
+    GetComponent<Rigidbody>().AddForce(waterCurrentForce * delta_current);
+  }
+}