<Window xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
Title="DrawingBrush as the Background">
<Window.Background>
<DrawingBrush>
<DrawingBrush.Drawing>
<DrawingGroup>
<GeometryDrawing Brush="Blue" Geometry="M 240,250
C 200,375 200,250 175,200
C 100,175 200,250 175,100
C 200,275 200,250 175,300
C 300,375 200,250 175,400
C 200,0 250,0 250,150 Z"/>
</DrawingGroup>
</DrawingBrush.Drawing>
</DrawingBrush>
</Window.Background>
</Window>