Text reveal

Main.xaml

<Grid
  xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
  xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
  <Grid.Resources>
    <Storyboard x:Key="anim">
       <!--Gradually unclip fs_text -->
       <RectAnimation Storyboard.TargetName="FsTextClip"
                      Storyboard.TargetProperty="Clip.Rect"
                      From="0,0,0,204.58"
                      To="0,0,613.66,204.58"
                      Duration="0:0:0.6"
                      BeginTime="0:0:1"/>

    </Storyboard>
  </Grid.Resources>
  <Grid.Triggers>
    <EventTrigger RoutedEvent="Grid.Loaded">
      <BeginStoryboard Storyboard="{StaticResource anim}"/>
    </EventTrigger>
  </Grid.Triggers>
  <Canvas x:Name="FsTextClip" Width="600" Height="200" Background="Silver">
    <Canvas.Clip>
      <RectangleGeometry Rect="0,0,0,204.58"/>
    </Canvas.Clip>
    <TextBlock Text="This is a text inside a canvas that will reveal with an animation."/>
  </Canvas>
</Grid>