title: How to Redraw 3D content in WPF
body: <p>So I have a bunch of lines that I have drawn using the ScreenSpaceLines3D class provided by <a href="http://3dtools.codeplex.com/" rel="nofollow">http://3dtools.codeplex.com/</a></p>
  
  <p>I was able to draw lines to my Viewport by defining them like </p>
  
  <pre><code>Point3D point0 = new Point3D(0, 0, 0);    
  Point3D point1 = new Point3D(5, 5, 0);    
  Point3D point2 = new Point3D(5, 5.5, 0);
  </code></pre>
  
  <p>and inside a button_click method, basically draw a bunch of lines like</p>
  
  <pre><code>ScreenSpaceLines3D wireframe = new ScreenSpaceLines3D();    
  wireframe.Points.Add(point0);    
  wireframe.Points.Add(point1);    
  wireframe.Points.Add(point2);    
  wireframe.Color = Colors.LightBlue;    
  wireframe.Thickness = 5;    
  this.mainViewport.Children.Add(wireframe);
  </code></pre>
  
  <p>I have also added a <code>point1.Z += 2;</code> to see a change in the lines after every click. </p>
  
  <p>I want to see only the same set of lines shifting, but new sets of lines end up getting draw after every click. I only need to refresh/redraw the same set with an updated set of points. I tried using <code>InvalidateVisual();</code> and <code>InvalidateArrange();</code> but did not work.</p>
  
  <p>Please advise!!</p>