public void SquareWindow()
        {
            var pixelScreen = new PixelScreenSpace(window);

            window.ViewportPixelSize = new Size(100, 100);
            Assert.AreEqual(Vector2D.Zero, pixelScreen.TopLeft);
            Assert.AreEqual(new Vector2D(100, 100), pixelScreen.BottomRight);
            Assert.AreEqual(new Rectangle(0, 0, 100, 100), pixelScreen.Viewport);
            Assert.AreEqual(new Vector2D(100, 100), pixelScreen.FromPixelSpace(new Vector2D(100, 100)));
            Assert.AreEqual(new Vector2D(50, 50), pixelScreen.FromPixelSpace(new Vector2D(50, 50)));
        }
        public void SquareWindowWithPixelSpace()
        {
            var screen = new PixelScreenSpace(window);

            Assert.AreEqual(Vector2D.Zero, screen.TopLeft);
            Assert.AreEqual(window.ViewportPixelSize, (Size)screen.BottomRight);
            Assert.AreEqual(new Rectangle(Vector2D.Zero, window.TotalPixelSize), screen.Viewport);
            Assert.AreEqual(new Vector2D(100, 100), screen.FromPixelSpace(new Vector2D(100, 100)));
            Assert.AreEqual(new Rectangle(10, 10, 80, 80),
                            screen.FromPixelSpace(new Rectangle(10, 10, 80, 80)));
            window.CloseAfterFrame();
        }