public void AddingPointsToEmptyBoundingBox()
        {
            var box = new shape.BoundingBox();
            var p1  = pt.Point(-5, 2, 0);
            var p2  = pt.Point(7, 0, -3);

            box.Add(p1);
            box.Add(p2);

            Assert.Equal(pt.Point(-5, 0, -3), box.Minimum);
            Assert.Equal(pt.Point(7, 2, 0), box.Maximum);
        }
        public void AddingBoxToAnother()
        {
            var box1 = new shape.BoundingBox(pt.Point(-5, -2, 0), pt.Point(7, 4, 4));
            var box2 = new shape.BoundingBox(pt.Point(8, -7, -2), pt.Point(14, 2, 8));

            box1.Add(box2);
            Assert.Equal(pt.Point(-5, -7, -2), box1.Minimum);
            Assert.Equal(pt.Point(14, 4, 8), box1.Maximum);
        }