App.xaml
<Application xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" StartupUri="MainWindow.xaml" />
MainWindow.xaml
<Window x:Class="HelloWorld.MainWindow" xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" Title="Hello World" > <StackPanel> <Button Width="100" Height="20" x:Name="button">テスト</Button> <Rectangle Width="500" Height="300"> <Rectangle.Fill> <!-- Viewportで横2つ、縦4つに指定する --> <VisualBrush Visual="{Binding ElementName=button}" Viewport="0, 0, 0.5, 0.25" TileMode="Tile" /> </Rectangle.Fill> </Rectangle> </StackPanel> </Window>