var spring = 50.0;
  var damper = 5.0;
  var drag = 10.0;
  var angularDrag = 5.0;
  var distance = 0.2;
  var pushForce = 0.2;
  var attachToCenterOfMass = false;
  
  var highlightMaterial : Material;
  private var highlightObject : GameObject;
  
  private var springJoint : SpringJoint;
  
  function Update()
  {
          var mainCamera = FindCamera();
          
          highlightObject = null;
          if( springJoint != null && springJoint.connectedBody != null )
          {
                  highlightObject = springJoint.connectedBody.gameObject;
          }
          else
          {
                  // We need to actually hit an object
                  var hitt : RaycastHit;
                  if( Physics.Raycast(mainCamera.ScreenPointToRay(Input.mousePosition),  hitt, 100 ) ) {
                          if( hitt.rigidbody && !hitt.rigidbody.isKinematic ) {
                                  highlightObject = hitt.rigidbody.gameObject;
                          }
                  }
          }
          
                  
          // Make sure the user pressed the mouse down
          if (!Input.GetMouseButtonDown (0))
                  return;
  
                  
          // We need to actually hit an object
          var hit : RaycastHit;
          if (!Physics.Raycast(mainCamera.ScreenPointToRay(Input.mousePosition),  hit, 100)) {
                  return;
          }
          // We need to hit a rigidbody that is not kinematic
          if (!hit.rigidbody || hit.rigidbody.isKinematic) {
                  return;
          }
          
          if (!springJoint)
          {
                  var go = new GameObject("Rigidbody dragger");
                  body = go.AddComponent ("Rigidbody");
                  springJoint = go.AddComponent ("SpringJoint");
                  body.isKinematic = true;
          }
          
          springJoint.transform.position = hit.point;
          if (attachToCenterOfMass)
          {
                  var anchor = transform.TransformDirection(hit.rigidbody.centerOfMass) + hit.rigidbody.transform.position;
                  anchor = springJoint.transform.InverseTransformPoint(anchor);
                  springJoint.anchor = anchor;
          }
          else
          {
                  springJoint.anchor = Vector3.zero;
          }
          
          springJoint.spring = spring;
          springJoint.damper = damper;
          springJoint.maxDistance = distance;
          springJoint.connectedBody = hit.rigidbody;
          
          DragObject(hit.distance, hit.point, mainCamera.ScreenPointToRay(Input.mousePosition).direction);
  }
  
  function DragObject (distance : float, hitpoint : Vector3, dir : Vector3)
  {
          var startTime = Time.time;
          var mousePos = Input.mousePosition;
          
          
          var oldDrag = springJoint.connectedBody.drag;
          var oldAngularDrag = springJoint.connectedBody.angularDrag;
          springJoint.connectedBody.drag = drag;
          springJoint.connectedBody.angularDrag = angularDrag;
          var mainCamera = FindCamera();
          while (Input.GetMouseButton (0))
          {
                  var ray = mainCamera.ScreenPointToRay (Input.mousePosition);
                  springJoint.transform.position = ray.GetPoint(distance);
                  yield;
          }
          
          if (Mathf.Abs(mousePos.x - Input.mousePosition.x) <= 2 && Mathf.Abs(mousePos.y - Input.mousePosition.y) <= 2 && Time.time - startTime < .2 && springJoint.connectedBody)
          {
                  dir.y = 0;
                  dir.Normalize();
                  springJoint.connectedBody.AddForceAtPosition(dir * pushForce, hitpoint, ForceMode.VelocityChange);
                  ToggleLight( springJoint.connectedBody.gameObject );
          }        
          
          
          if (springJoint.connectedBody)
          {
                  springJoint.connectedBody.drag = oldDrag;
                  springJoint.connectedBody.angularDrag = oldAngularDrag;
                  springJoint.connectedBody = null;
          }
  }
  
  static function ToggleLight( go : GameObject )
  {                
          var theLight : Light = go.GetComponentInChildren(Light);
          if( !theLight )
                  return;
                  
          theLight.enabled = !theLight.enabled;
          var illumOn = theLight.enabled;
          var renderers = go.GetComponentsInChildren(MeshRenderer);
          for( var r : MeshRenderer in renderers )
          {
                  if( r.gameObject.layer == 1 )
                  {
                          r.material.shader = Shader.Find(illumOn ? "Self-Illumin/Diffuse" : "Diffuse");
                  }
          }
  }
  
  function FindCamera ()
  {
          if (camera)
                  return camera;
          else
                  return Camera.main;
  }
  
  function OnPostRender()
  {
          if( highlightObject == null )
                  return;
                  
          var go = highlightObject;
          highlightMaterial.SetPass( 0 );
          var meshes = go.GetComponentsInChildren(MeshFilter);
          for( var m : MeshFilter in meshes )
          {
                  Graphics.DrawMeshNow( m.sharedMesh, m.transform.position, m.transform.rotation );
          }
  }