<Canvas xmlns="http://schemas.microsoft.com/client/2007">
        <Canvas Opacity="0.5">
      	        <Rectangle Fill="Red" StrokeThickness="10" Stroke="Green" Width="100" Height="100" />
                <!-- this should be drawn over the previous rectangle (no blending) -->
                <Rectangle Canvas.Left="50" Canvas.Top="50" Fill="Blue" Width="100"
Height="100" />
        </Canvas>
	<!-- these should overlap -->
	<Rectangle Opacity="0.5" Fill="Red" StrokeThickness="10" Stroke="Green" Width="100" Height="100" Canvas.Top="200"/>
	<Rectangle Opacity="0.5" Canvas.Top="250" Canvas.Left="50" Fill="Blue" Width="100" Height="100" />
</Canvas>

