Programming .NET 3.5

Transformations

While there is much that can be written about 2-D graphics, one of the more interesting (and at times confusing) aspects of taking control of graphics is transformations. Here, we'll look at an example of the art of transforming the up/down orientation of the page.

WPF makes simple transformations very simple, as shown in Example 3-9.

Example 3-9. A simple transformation

<Window
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    Title="Programming .NET 3.5 | Transformations: Rotate">
   <Border Margin="30"
       HorizontalAlignment="Left" VerticalAlignment="Top"
       BorderBrush="Black" BorderThickness="1" >
      <StackPanel Orientation="Vertical">
         <Button Content="Top Button" Opacity="1" />
         <Button Content="Middle Button" Opacity="1" />
         <Button Content="Rotated Button">
            <Button.RenderTransform>
               <RotateTransform Angle="45" />
            </Button.RenderTransform>
         </Button>

      </StackPanel>
   </Border>
</Window>

This example creates three buttons. The third button has a RenderTransform applied to it, and the RenderTransform has a child element, RotateTransform, whose attribute is an angle (in this case, 45 degrees). The button is rendered with a 45-degree clockwise rotation, as shown in Figure 3-15.

Figure 3-15. A 45-degree rotation