using System;

using System.Windows;

using System.Windows.Input;

using System.Windows.Media;

namespace LY.VaryTheBackGround

{

    public class VaryTheBackGround : Window

    {

        SolidColorBrush brush = new SolidColorBrush(Colors.Beige);

        [STAThread]

        public static void Main()

        {

            new Application().Run(new VaryTheBackGround());

        }

        public VaryTheBackGround()

        {

            Title = "Vary the Background";

            Width = 384;

            Height = 384;

            WindowStartupLocation = WindowStartupLocation.CenterScreen;

            WindowStyle = WindowStyle.ToolWindow;

            ResizeMode = ResizeMode.CanMinimize;

            Background = brush;

        }

        protected override void OnMouseMove(MouseEventArgs e)

        {

            base.OnMouseMove(e);

            double width = ActualWidth -

                2 * SystemParameters.ResizeFrameVerticalBorderWidth;

            double height = ActualHeight -

                2 * SystemParameters.ResizeFrameHorizontalBorderHeight -

                SystemParameters.CaptionHeight;

            Point ptMouse = e.GetPosition(this);

            Point ptCenter = new Point(Width / 2, Height / 2);

            Vector vectMouse = ptMouse - ptCenter;

            double angle = Math.Atan2(vectMouse.Y, vectMouse.X);

            Color cr = brush.Color;

            cr.ScR = cr.ScG = cr.ScB = (float)angle;

            brush.Color = cr;

        }

    }

}