anchor.diff:          
           //  Get the OpenGL instance.
           let gl = args.OpenGL       
  -     
  +        let s = sender :?> SharpGL.WPF.OpenGLControl
           //  Create the projection matrix for the screen size.
  -        scene.CreateProjectionMatrix(gl, 800.f, 600.f)//(float32 actualWidth), (float)ActualHeight);
  -        
  -
  -
  -
  +        scene.CreateProjectionMatrix(gl, float32 s.ActualWidth, float32 s.ActualHeight)//actualWidth, actualHeight)
  +        
  +    let ComboBox_Selected(sender : obj, args) =
  +        comboRenderModeSelectedIndex <- (sender :?> ComboBox).SelectedIndex
  +        
  +    let CheckBox_Selected(sender : obj, args) =
  +        checkBoxUseToonShaderIsChecked <- (sender :?> CheckBox).IsChecked.Value  
   
   let loadXamlWindow (filename:string) =
       let reader = XmlReader.Create(filename)
  
positive.code:         vertexBuffer.Bind(gl)
          vertices |> Array.map (fun v -> v.to_array())
          |> Array.iter (fun x -> vertexBuffer.SetData(gl, vertexAttributeLocation, x, false, 3))
           
          //let normalBuffer = new VertexBuffer()
          normalBuffer.Create(gl)
          normalBuffer.Bind(gl)
          normals |> Array.map (fun v -> v.to_array())
          |> Array.iter (fun x -> normalBuffer.SetData(gl, normalAttributeLocation, x, false, 3))     
  
      let CreateIndexBuffer(gl) =
          
  
negative.code:         let mutable dv = new vec3()
          dv.x <- -1.5f*b*(Sin (1.5f*u))*(Cos u) - (a + b*(Cos (1.5f*u))*(Sin u))
          dv.y <- -1.5f*b*(Sin (1.5f*u))*(Sin u) + (a + b*(Cos (1.5f*u))*(Cos u))
          dv.z <-  1.5f*c*(Cos (1.5f*u))
              
          let q = glm.normalize(dv)
          let qvn = glm.normalize(new vec3(q.y, -q.x, 0.0f))
  