Translate then Rotate

   
  

<Window x:Class="Workspace.DockExample"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    Title="Workspace" Width="640" Height="480">
            <Canvas Height="200" Width="200">
                <Polyline
                  Points="25,25 0,50 25,75 50,50 25,25 25,0" Stroke="Blue" StrokeThickness="10"
                  Canvas.Left="75" Canvas.Top="50">
                    <Polyline.RenderTransform>
                
                    
                        <TransformGroup>
                            <TransformGroup.Children>
                                <TransformCollection>
                                    <TranslateTransform X="50" Y="0" />
                                    <RotateTransform CenterX="25" CenterY="50" Angle="45" />
                                </TransformCollection>
                            </TransformGroup.Children>
                        </TransformGroup>

                    </Polyline.RenderTransform>
                </Polyline>
                <Polyline Points="25,25 0,50 25,75 50,50 25,25 25,0" Stroke="Blue" StrokeThickness="10"
                  Opacity="0.25" Canvas.Left="75" Canvas.Top="50" />

            </Canvas>

</Window>