WPF 2D Combined Geometry

<Window x:Class="WpfApplication17.MainWindow"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
Title="Combined Geometry" Height="340" Width="300">
<Window.Resources>
<SolidColorBrush x:Key="MyGrayGridBrush" Color="YellowGreen"/>
</Window.Resources>
<Border Margin="5" BorderBrush="Black" BorderThickness="1"  
Background="{StaticResource MyGrayGridBrush}" 
HorizontalAlignment="Left">
<Canvas Width="300" Height="340" Margin="5">
<Grid>
<Grid.ColumnDefinitions>
	<ColumnDefinition Width="140"/>
	<ColumnDefinition Width="140"/>
</Grid.ColumnDefinitions>
<StackPanel Grid.Column="0">
	<TextBlock FontSize="12pt" Text="Union" 
                Margin="40,5,5,10"/>
	<Path Fill ="LightBlue" Stroke="Blue">
		<Path.Data>
			<CombinedGeometry 
                GeometryCombineMode="Union">
				<CombinedGeometry.Geometry1>
					<EllipseGeometry  
                        Center="50,50" 
                        RadiusX="50" 
                        RadiusY="50"/>
				</CombinedGeometry.Geometry1>
				<CombinedGeometry.Geometry2>
					<EllipseGeometry  
                        Center="80,50"  
                        RadiusX="50" 
                        RadiusY="50"/>
				</CombinedGeometry.Geometry2>
			</CombinedGeometry>
		</Path.Data>
	</Path>
 
	<TextBlock FontSize="12pt" Text="Xor" 
                Margin="45,15,5,10"/>
	<Path Fill ="LightBlue" Stroke="Blue">
		<Path.Data>
			<CombinedGeometry  
                GeometryCombineMode="Xor">
				<CombinedGeometry.Geometry1>
					<EllipseGeometry  
                        Center="50,50" 
                        RadiusX="50"  
                        RadiusY="50"/>
				</CombinedGeometry.Geometry1>
				<CombinedGeometry.Geometry2>
					<EllipseGeometry  
                        Center="80,50" 
                        RadiusX="50" 
                        RadiusY="50"/>
				</CombinedGeometry.Geometry2>
			</CombinedGeometry>
		</Path.Data>
	</Path>
</StackPanel>
 
<StackPanel Grid.Column="1">
	<TextBlock FontSize="12pt" 
        Text="Intersect" Margin="30,5,5,10"/>
	<Path Fill ="LightBlue" Stroke="Blue"  
            Margin="5,0,0,0">
		<Path.Data>
			<CombinedGeometry  
                GeometryCombineMode="Intersect">
				<CombinedGeometry.Geometry1>
					<EllipseGeometry 
                        Center="50,50" 
                        RadiusX="50" 
                        RadiusY="50"/>
				</CombinedGeometry.Geometry1>
				<CombinedGeometry.Geometry2>
					<EllipseGeometry  
                        Center="80,50" 
                        RadiusX="50" 
                        RadiusY="50"/>
				</CombinedGeometry.Geometry2>
			</CombinedGeometry>
		</Path.Data>
	</Path>
 
	<TextBlock FontSize="12pt" Text="Exclude" 
                Margin="35,15,5,10"/>
	<Path Fill ="LightBlue" Stroke="Blue" 
            Margin="10,0,0,0">
		<Path.Data>
			<CombinedGeometry 
                GeometryCombineMode="Exclude">
				<CombinedGeometry.Geometry1>
					<EllipseGeometry  
                        Center="50,50" RadiusX="50" 
                        RadiusY="50"/>
				</CombinedGeometry.Geometry1>
				<CombinedGeometry.Geometry2>
					<EllipseGeometry 
                        Center="80,50" 
                        RadiusX="50" 
                        RadiusY="50"/>
				</CombinedGeometry.Geometry2>
			</CombinedGeometry>
		</Path.Data>
	</Path>
</StackPanel>
</Grid>
</Canvas>
</Border>
</Window>

reference : Practical WPF Graphics Programming