Анимация синусоиды

public partial class MainWindow : Window
{
    private WriteableBitmap _writeableBitmap;
    private int _n = 0;
 
    public MainWindow()
    {
        InitializeComponent();
          
        this.Loaded += new RoutedEventHandler(MainWindow_Loaded);
    }
 
    void MainWindow_Loaded(object sender, RoutedEventArgs e)
    {
        Image image = new Image();
        RenderOptions.SetBitmapScalingMode(image, BitmapScalingMode.NearestNeighbor);
        RenderOptions.SetEdgeMode(image, EdgeMode.Aliased);
            
 
        this.Content = image;
 
        _writeableBitmap = new WriteableBitmap(
            360,
            360,
            96,
            96,
            PixelFormats.Bgr32,
            null);
 
        image.Source = _writeableBitmap;
           
        DispatcherTimer timer = new DispatcherTimer();
        timer.Interval = TimeSpan.FromMilliseconds(10);
        timer.Tick += new EventHandler(timer_Tick);
        timer.Start();
    }        
 
    void timer_Tick(object sender, EventArgs e)
    {
        Dispatcher.BeginInvoke(DispatcherPriority.Background, new Action(() =>
        {
 
            for (double x = 0; x < 360; x+=.5) // 360 degrees
            {
                ErasePixel((int)x, (int)(Math.Sin(DegreesToRadians(x + _n - 1)) * 50) + 50); // sin produces a value between -1 and 1, so, +50 so we don't plot on the negative axis
            }
 
 
            for (double x = 0; x < 360; x+=.5) // 360 degrees
            {
                DrawPixel((int)x, (int)(Math.Sin(DegreesToRadians(x + _n)) * 50) + 50); // sin produces a value between -1 and 1, so, +50 so we don't plot on the negative axis
            }
            _n++;
        }));
 
       
    }
 
    double DegreesToRadians(double degrees)
    {
        return degrees*(Math.PI/180);
    }
 
    void ErasePixel(int x, int y)
    {
        byte[] ColorData = { 0, 0, 0, 0 }; // B G R
 
        Int32Rect rect = new Int32Rect(
                x,
                y,
                1,
                1);
 
        _writeableBitmap.WritePixels(rect, ColorData, 4, 0);
    }
 
    void DrawPixel(int x, int y)
    {            
        // Reserve the back buffer for updates.
        _writeableBitmap.Lock();
 
        unsafe
        {
            // Get a pointer to the back buffer. 
            int pBackBuffer = (int)_writeableBitmap.BackBuffer;
 
            // Find the address of the pixel to draw.
            pBackBuffer += y * _writeableBitmap.BackBufferStride;
            pBackBuffer += x * 4;
 
            // Compute the pixel's color. 
            int color_data = 255 << 16; // R
            color_data |= 128 << 8;   // G
            color_data |= 255 << 0;   // B 
 
            // Assign the color data to the pixel.
            *((int*)pBackBuffer) = color_data;
        }
 
        // Specify the area of the bitmap that changed.
        _writeableBitmap.AddDirtyRect(new Int32Rect(x, y, 1, 1));
 
        // Release the back buffer and make it available for display.
        _writeableBitmap.Unlock();
    }
}