Draw special background - wpf

Question

Is it possible in WPF to draw the background of a window the following way:
the background of the window is for instance white
vertical colored lines of 20 pixels width with a same-size gap in between, so that you get a red-striped pattern
horizontal colored lines of 20 pixels height in the same color, also with a same-size gap in between
the areas where the horizontal and vertical red lines overlap each other should be shown in white again, so that you get kind of a checkered pattern
I know how to draw lines in WPF and I know how to repeat a drawing to fill the whole background, but I don't know how the manage the part with the overlapping colors vanishing.

Answer 1

Not sure how large the gap is supposed to be. You may however adjust a DrawingBrush like this:
<Window.Background>
<DrawingBrush TileMode="Tile" ViewportUnits="Absolute" Viewport="0,0,100,100">
<DrawingBrush.Drawing>
<DrawingGroup>
<GeometryDrawing Brush="White">
<GeometryDrawing.Geometry>
<RectangleGeometry Rect="0,0,100,100"/>
</GeometryDrawing.Geometry>
</GeometryDrawing>
<GeometryDrawing
Geometry="M50,0 L50,40 M50,60 L50,100 M0,50 L40,50 M60,50 L100,50">
<GeometryDrawing.Pen>
<Pen Brush="Red" Thickness="20"/>
</GeometryDrawing.Pen>
</GeometryDrawing>
</DrawingGroup>
</DrawingBrush.Drawing>
</DrawingBrush>
</Window.Background>
Or with another TileMode:
<Window.Background>
<DrawingBrush TileMode="FlipXY" ViewportUnits="Absolute" Viewport="0,0,50,50">
<DrawingBrush.Drawing>
<DrawingGroup>
<GeometryDrawing Brush="White">
<GeometryDrawing.Geometry>
<RectangleGeometry Rect="0,0,50,50"/>
</GeometryDrawing.Geometry>
</GeometryDrawing>
<GeometryDrawing Geometry="M0,45 L40,45 M45,0 L45,40">
<GeometryDrawing.Pen>
<Pen Brush="Red" Thickness="10"/>
</GeometryDrawing.Pen>
</GeometryDrawing>
</DrawingGroup>
</DrawingBrush.Drawing>
</DrawingBrush>
</Window.Background>