public void TestSceneGraph( )
        {
            Scene scene = new Scene( );

            SceneObject subTree = new SceneObject( new SceneObject( ), new SceneObject( ) );

            SceneObject root =
                new SceneObject
                (
                    new SceneObject( ),
                    subTree,
                    new SceneObject( )
                );

            scene.Objects.Add( root );
            root.CheckAddCount( 1 );

            root.RemoveChild( subTree );
            subTree.CheckAddCount( 0 );
        }