<StackPanel xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
xmlns:d="http://schemas.microsoft.com/expression/interactivedesigner/2006"
mc:Ignorable="d"
x:Class="PaintDrawExamples.DynamicClipping"
Width="640" Height="480">
<StackPanel.Resources>
<Storyboard x:Key="OnLoaded"/>
</StackPanel.Resources>
<StackPanel.Triggers>
<EventTrigger RoutedEvent="FrameworkElement.Loaded">
<BeginStoryboard x:Name="OnLoaded_BeginStoryboard" Storyboard="{DynamicResource OnLoaded}"/>
</EventTrigger>
</StackPanel.Triggers>
<Canvas Height="100" x:Name="Canvas" Width="436">
<Canvas.Clip>
<PathGeometry>
<PathFigure StartPoint="1,5" IsClosed="True" IsFilled="True">
<BezierSegment IsSmoothJoin="True" Point1="2,2" Point2="26,1" Point3="24,127" IsStroked="True"/>
<BezierSegment IsSmoothJoin="True" Point1="1,1" Point2="14,9" Point3="19,5" IsStroked="True"/>
<BezierSegment IsSmoothJoin="True" Point1="14,11" Point2="18,-22.5" Point3="24,-2" IsStroked="True"/>
<BezierSegment IsSmoothJoin="True" Point1="26,-200" Point2="29,1" Point3="300,5" IsStroked="True"/>
</PathFigure>
</PathGeometry>
</Canvas.Clip>
<Rectangle d:LayoutOverrides="Height" Stroke="{x:Null}" Fill="Red" Width="436" Height="100" x:Name="Rectangle" Canvas.Left="0" Canvas.Top="0"/>
<Label Background="Black" x:Name="Label" Content="This is my clipped space." Canvas.Left="46" Canvas.Top="26" d:IsHidden="True"/>
</Canvas>
</StackPanel>
//File:Window.xaml.cs
using System;
using System.IO;
using System.Net;
using System.Windows;
using System.Windows.Input;
using System.Windows.Controls;
using System.Windows.Data;
using System.Windows.Media;
using System.Windows.Media.Animation;
using System.Windows.Navigation;
namespace PaintDrawExamples
{
public partial class DynamicClipping
{
public DynamicClipping()
{
this.InitializeComponent();
this.Canvas.VerticalAlignment = VerticalAlignment.Center;
this.Canvas.HorizontalAlignment = HorizontalAlignment.Center;
CompositionTarget.Rendering += CompositionTarget_Rendering;
}
private void CompositionTarget_Rendering(object sender, EventArgs e)
{
Point mousePos = Mouse.GetPosition(this.Canvas);
Geometry clippingRegion = this.Canvas.Clip;
TranslateTransform newPos = new TranslateTransform();
newPos.X = mousePos.X - (this.Canvas.Width / 2);
newPos.Y = mousePos.Y - (this.Canvas.Height / 2);
clippingRegion.Transform = newPos;
}
}
}
