title: How to Clip content with rounded corners in Windows Store App
body: <p>I've attempted to have a <code>&lt;Grid/&gt;</code> (with interactive stuff inside, not just an image) <strong>clipped</strong> with rounded corners (a <code>&lt;Border/&gt;</code> or a <code>&lt;Rectangle/&gt;</code>, whatever works).</p>
  
  <p>I've attempted multiple solutions, but none of them was compatible with a Windows Store App.</p>
  
  <p>No brush:</p>
  
  <blockquote>
    <ul>
    <li>RadialGradientBrush is not supported in a Windows App project.</li>
    <li>DrawingBrush is not supported in a Windows App project.</li>
    <li>The type 'VisualBrush' was not found. Verify that you are not missing an assembly reference and that all referenced assemblies have been built.</li>
    </ul>
  </blockquote>
  
  <p>No mask:</p>
  
  <blockquote>
    <ul>
    <li>The attachable property 'OpacityMask' was not found in type 'Image'.</li>
    <li>The attachable property 'OpacityMask' was not found in type 'StackPanel'.</li>
    <li>The attachable property 'OpacityMask' was not found in type 'Grid'.</li>
    </ul>
  </blockquote>
  
  <p>No rounded geometry:</p>
  
  <blockquote>
    <ul>
    <li>The property 'RadiusX' was not found in type 'RectangleGeometry'.</li>
    <li>MultiBinding is not supported in a Windows App project.</li>
    </ul>
  </blockquote>
  
  <p>Is it something technically impossible in a C#/XAML Windows store app?</p>