SFML .Net with WPF

MainWindow.xaml

<Window x:Class="WpfApplication1.MainWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        xmlns:wf="clr-namespace:System.Windows.Forms;assembly=System.Windows.Forms"
        Title="MainWindow" Height="350" Width="525">
    <Grid x:Name="MyGrid">
        <Grid.RowDefinitions>
            <RowDefinition Height="*"/>
            <RowDefinition Height="*"/>
        </Grid.RowDefinitions>

        <WindowsFormsHost x:Name="FormHost" Grid.Row="0">
            
        </WindowsFormsHost>
        
        <Button Grid.Row="1" HorizontalAlignment="Left" VerticalAlignment="Bottom" Content="awdawd"
                Margin="4" Padding="8 2"/>
    </Grid>
</Window>

MainWindow.xaml.cs

namespace WpfApplication1
{
    using System;
    using SFML.Graphics;
    using SFML.Window;
    using SFML.System;
    
    /// <summary>
    /// Interaction logic for MainWindow.xaml
    /// </summary>
    public partial class MainWindow : System.Windows.Window
    {
        private RenderWindow _renderWindow;

        private CircleShape _circle;

        public MainWindow()
        {
            InitializeComponent();

            this._circle = new CircleShape();
            this._circle.Radius = 20;
            this._circle.FillColor = new Color(255, 0, 255, 255);
            this._circle.Position = new Vector2f(2, 2);

            //need to use this to prevent base.OnPaint and base.OnPaintBackground from erasing contents
            var mysurf = new MyDrawingSurface(); 
            this.FormHost.Child = mysurf;
            SetdoubleBuffered(mysurf); //same results whether or not i do this.
            
            var context = new ContextSettings { DepthBits = 24 };
            this._renderWindow = new RenderWindow(mysurf.Handle);
            this._renderWindow.MouseButtonPressed += _renderWindow_MouseButtonPressed;
            
            var timer = new System.Windows.Threading.DispatcherTimer();
            timer.Interval = new TimeSpan(0, 0, 0, 0, 1000 / 60);
            timer.Tick += timer_Tick;
            timer.Start();
        }

        public static void SetdoubleBuffered(System.Windows.Forms.Control c)
        {
            System.Reflection.PropertyInfo aProp =
                typeof(System.Windows.Forms.Control).GetProperty(
                "DoubleBuffered", System.Reflection.BindingFlags.NonPublic | System.Reflection.BindingFlags.Instance);

            aProp.SetValue(c, true, null);
        }

        void _renderWindow_MouseButtonPressed(object sender, MouseButtonEventArgs e)
        {
            //e.X and e.Y are actually what they should be. top-left of the visible area is 0,0
            this._circle.Position = new Vector2f(e.X, e.Y);
        }

        void timer_Tick(object sender, EventArgs e)
        {
            this._renderWindow.DispatchEvents();
            
            Random rand = new Random();
            var clearColor = new Color((byte)rand.Next(255), (byte)rand.Next(255), (byte)rand.Next(255));
            this._renderWindow.Draw(this._circle);
            this._renderWindow.Clear(clearColor); //this works, it flashes all sorts of colors

            //trying several types of things to draw in the hopes that one will work. so far no luck.
            var rect = new RectangleShape();
            rect.Position = new Vector2f(-10, -10);
            rect.Size = new Vector2f(100, 200);
            rect.FillColor = Color.Blue;

            Vertex[] line = new Vertex[] 
                    {
                        new Vertex(new Vector2f(0,0)) {Color = Color.White},
                        new Vertex(new Vector2f(50,100)) {Color = Color.Red}
                    };

            //tried drawing before clearing, after calling Display(), none worked.
            this._renderWindow.Draw(line, PrimitiveType.Lines);
            this._renderWindow.Draw(rect);
            this._renderWindow.Draw(this._circle);

            this._renderWindow.Display();
        }

        public class MyDrawingSurface : System.Windows.Forms.Control
        {
            protected override void OnPaint(System.Windows.Forms.PaintEventArgs e)
            {
                //base.OnPaint(e);
            }

            protected override void OnPaintBackground(System.Windows.Forms.PaintEventArgs pevent)
            {
                //base.OnPaintBackground(pevent);
            }
        }
    }
}