using System;
using System.Windows;
using System.Windows.Input;
using System.Windows.Media;
public class MainClass : Window
{
SolidColorBrush brush = new SolidColorBrush(Colors.Black);
[STAThread]
public static void Main()
{
Application app = new Application();
app.Run(new MainClass());
}
public MainClass()
{
Width = 400;
Height = 400;
Background = brush;
}
protected override void OnMouseMove(MouseEventArgs args)
{
double width = 330;
double height = 350;
Point ptMouse = args.GetPosition(this);
Point ptCenter = new Point(width / 2, height / 2);
Vector vectMouse = ptMouse - ptCenter;
double angle = Math.Atan2(vectMouse.Y, vectMouse.X);
Vector vectEllipse = new Vector(width / 2 * Math.Cos(angle),height / 2 * Math.Sin(angle));
Byte byLevel = 123;
Color clr = brush.Color;
clr.R = clr.G = clr.B = byLevel;
brush.Color = clr;
}
}