private void updateStackingManipulation()
    {
        if (Input.GetKeyUp("t"))
        {
            TestScript script = (TestScript)GameObject.Find("InputController").GetComponent("TestScript");
            script.testStack();                     // place an object -> skip selection step
        }
        if (Input.GetKeyUp("p"))
        {
            TestScript script = (TestScript)GameObject.Find("InputController").GetComponent("TestScript");
            script.testParentMove();
        }
        if (Input.GetKeyUp("m"))
        {
            TestScript script = (TestScript)GameObject.Find("InputController").GetComponent("TestScript");
            script.testParentRotate();
        }
        if (Input.GetKeyUp("l"))
        {
            ObjectScript script = (ObjectScript)GameObject.Find("Tafel").GetComponent("ObjectScript");
            script.detachChild(GameObject.Find("schaal1"));
        }

        if (stackScript.isActive)
        {
            if (stackScript.gridModus)
            {
                if (Input.GetKeyUp("left"))
                {
                    stackScript.goToNextAvailablePositionLeft();
                }
                if (Input.GetKeyUp("right"))
                {
                    stackScript.goToNextAvailablePositionRight();
                }
                if (Input.GetKeyUp("up"))
                {
                    stackScript.goToNextAvailablePositionTop();
                }
                if (Input.GetKeyUp("down"))
                {
                    stackScript.goToNextAvailablePositionDown();
                }
            }
            else
            {
                if (Input.GetKey("left"))
                {
                    stackScript.goToLeft();
                }
                if (Input.GetKey("right"))
                {
                    stackScript.goToRight();
                }
                if (Input.GetKey("up"))
                {
                    stackScript.goToTop();
                }
                if (Input.GetKey("down"))
                {
                    stackScript.goToBottom();
                }
            }


            if (Input.GetKeyUp("y") && stackScript.gridModus)
            {
                stackScript.goToNextAvailablePosition();                 // scrolling  left-right, bottom-up
            }
            if (Input.GetKeyUp("u"))
            {
                stackScript.goToNextPossibleStackedObject();                 // scrolling between possible object
            }
            if (Input.GetKeyUp("i"))
            {
                stackScript.Abort();                 // abort this manipulation
            }
            if (Input.GetKeyUp("o"))
            {
                stackScript.End();                 // end this manipulation
            }
        }
    }