Avalonia/samples/ControlCatalog/Pages/LayoutTransformControlPage.xaml

<UserControl xmlns="https://github.com/avaloniaui"
             xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
             x:Class="ControlCatalog.Pages.LayoutTransformControlPage">
  <DockPanel>
    <Grid ColumnDefinitions="Auto,*" RowDefinitions="Auto" Margin="16" DockPanel.Dock="Top">
      <TextBlock Grid.Column="0" Grid.Row="0">Rotation</TextBlock>
      <Slider Name="rotation" Maximum="360" Grid.Column="1" Grid.Row="0"/>
    </Grid>

    <Grid ColumnDefinitions="24,Auto,24" 
          RowDefinitions="24,Auto,24"
          HorizontalAlignment="Center"
          VerticalAlignment="Center">
      <Border Background="{DynamicResource SystemAccentColor}" Grid.Column="1" Grid.Row="0"/>
      <Border Background="{DynamicResource SystemAccentColor}" Grid.Column="0" Grid.Row="1"/>
      <Border Background="{DynamicResource SystemAccentColor}" Grid.Column="2" Grid.Row="1"/>
      <Border Background="{DynamicResource SystemAccentColor}" Grid.Column="1" Grid.Row="2"/>

      <LayoutTransformControl Name="layoutTransform" Grid.Column="1" Grid.Row="1">
        <LayoutTransformControl.LayoutTransform>
          <RotateTransform Angle="{Binding #rotation.Value}"/>
        </LayoutTransformControl.LayoutTransform>
          <Button Background="White">Layout Transform</Button>
      </LayoutTransformControl>
    </Grid>
  </DockPanel>
</UserControl>