How can I animate a rectangle clipping path?

How would you go about animating some RectangleGeometry that is used as a clipping path?

Something like this...

<Storyboard>
<PointAnimation

Storyboard.TargetName="clipRectGeom" Storyboard.TargetProperty="Rect" To="0,0

50,50" />
</Storyboard>

<Image

Source="image.jpg" Width="213" Height="120">
<Image.Clip>

<RectangleGeometry x:Name="clipRectGeom" Rect="10,10 50,50"

</Image.Clip>
</Image>

That breaks because the To value isn't Point data I imagine.

There must be a way to animate a rectangular clipping path, but it has us stumped.

[1065 byte] By [JasonGrunstra] at [2008-2-25]

Silverlight (formerly WPF/E) Hot Topic