Polygon Stretch="Uniform
<Page xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" x:Class="Microsoft.Samples.Graphics.RectangleExample" WindowTitle="Rectangle Example"> <Canvas> <Polygon Height="100" Width="50" Points="0,0 10,10 0,10" Fill="Blue" Stretch="Uniform"/> </Canvas> </Page>