public void CalcualteViewMatrix_with_simple_values()
        {
            var position = new Vector3(0, 0, 3);
            var direction = new Vector3(0, 0, -1);
            var up = new Vector3(0, 1, 0);

            var view = Stand.CalculateViewMatrix(position, direction, up);

            var xna = Microsoft.Xna.Framework.Matrix.CreateLookAt(
                position.ToXna(), (position + direction).ToXna(), up.ToXna());

            Assert.AreEqual(xna.ToMath(), view);
        }