var speed = 6.0;
  var jumpSpeed = 8.0;
  var gravity = 20.0;
  
  private var moveDirection = Vector3.zero;
  private var grounded : boolean = false;
  
  function FixedUpdate() {
          if (grounded) {
                  // We are grounded, so recalculate movedirection directly from axes
                  moveDirection = new Vector3(Input.GetAxis("Horizontal"), 0, Input.GetAxis("Vertical"));
                  moveDirection = transform.TransformDirection(moveDirection);
                  moveDirection *= speed;
                  
                  if (Input.GetButton ("Jump")) {
                          moveDirection.y = jumpSpeed;
                  }
          }
  
          // Apply gravity
          moveDirection.y -= gravity * Time.deltaTime;
          
          // Move the controller
          var controller : CharacterController = GetComponent(CharacterController);
          var flags = controller.Move(moveDirection * Time.deltaTime);
          grounded = (flags & CollisionFlags.CollidedBelow) != 0;
  }
  
  @script RequireComponent(CharacterController)