MagnifyGlassEffect Class

Creates an effect that can be used to zoom in on a portion of an image with options to specify size, shape and color of the magnify glass and crosshairs.

Object Model

Syntax

Visual Basic
C#
Objective-C
Java
C++

public class MagnifyGlassEffect : System.Windows.Media.Effects.ShaderEffect, System.Windows.Media.Animation.IAnimatable

'Declaration
 
Public Class MagnifyGlassEffect 
   Inherits System.Windows.Media.Effects.ShaderEffect
   Implements System.Windows.Media.Animation.IAnimatable

'Usage
 
Dim instance As MagnifyGlassEffect

public ref class MagnifyGlassEffect : public System.Windows.Media.Effects.ShaderEffect, System.Windows.Media.Animation.IAnimatable

Example

Visual Basic
C#
WinRT C#
WinRT JavaScript
Silverlight C#
Silverlight VB

Copy Code

Imports Leadtools
Imports Leadtools.Codecs
Imports Leadtools.ImageProcessing
Imports Leadtools.Windows.Controls
Imports Leadtools.Windows.Media
Imports Leadtools.Windows.Media.Effects

Class MagnifyGlassEffectExampleWindow
   Inherits Window
   Private theViewer As ImageViewer
   Public Sub New()
      Dim sp As New StackPanel()
      Content = sp

      theViewer = New ImageViewer()

      theViewer.HorizontalAlignment = HorizontalAlignment.Center
      theViewer.VerticalAlignment = VerticalAlignment.Top
      theViewer.ImageHorizontalAlignment = HorizontalAlignment.Left
      theViewer.ImageVerticalAlignment = VerticalAlignment.Top

      sp.Children.Add(theViewer)

      ' Load an image into the viewer
      theViewer.Source = New BitmapImage(New Uri(System.IO.Path.Combine(LEAD_VARS.ImagesDir, "Cannon.jpg")))

      Title = "MagnifyGlassEffect - Click and and move the mouse cursor on the image to see the effect"

      AddHandler theViewer.PreviewMouseDown, AddressOf theViewer_PreviewMouseDown
      AddHandler theViewer.MouseMove, AddressOf theViewer_MouseMove
      AddHandler theViewer.MouseUp, AddressOf theViewer_MouseUp
   End Sub

   Private Sub theViewer_PreviewMouseDown(ByVal sender As Object, ByVal e As MouseButtonEventArgs)
      Dim effect As New MagnifyGlassEffect()

      Dim pos As Point = e.GetPosition(theViewer)

      Dim source As BitmapSource = DirectCast(theViewer.Source, BitmapSource)
      If Not source Is Nothing Then
         effect.Center = New Point( _
            (1.0 * pos.X) / source.PixelWidth, _
            (1.0 * pos.Y) / source.PixelHeight)

         effect.Radius = 0.25
         effect.AspectRatio = 1.0
         effect.ScaleFactor = 2.0
         effect.Color = Colors.Blue
         effect.Border = 1
         effect.CrossHairs = 1
         theViewer.ImageEffect = effect
      End If
   End Sub

   Private Sub theViewer_MouseMove(ByVal sender As Object, ByVal e As MouseEventArgs)
      Dim effect As MagnifyGlassEffect = DirectCast(theViewer.ImageEffect, MagnifyGlassEffect)
      If Not effect Is Nothing Then
         Dim pos As Point = e.GetPosition(theViewer)

         Dim source As BitmapSource = DirectCast(theViewer.Source, BitmapSource)
         If Not source Is Nothing Then
            effect.Center = New Point( _
               (1.0 * pos.X) / source.PixelWidth, _
               (1.0 * pos.Y) / source.PixelHeight)
         End If
      End If
   End Sub

   Private Sub theViewer_MouseUp(ByVal sender As Object, ByVal e As MouseButtonEventArgs)
      If Not theViewer.ImageEffect Is Nothing Then
         theViewer.ImageEffect = Nothing
      End If
   End Sub
End Class

Public NotInheritable Class LEAD_VARS
Public Const ImagesDir As String = "C:\Users\Public\Documents\LEADTOOLS Images"
End Class

using Leadtools;
using Leadtools.Codecs;
using Leadtools.ImageProcessing;
using Leadtools.Windows.Controls;
using Leadtools.Windows.Media;
using Leadtools.Windows.Media.Effects;

class MagnifyGlassEffectExampleWindow : Window
{
   private ImageViewer theViewer;
   public MagnifyGlassEffectExampleWindow()
   {
      StackPanel sp = new StackPanel();
      Content = sp;

      theViewer = new ImageViewer();

      theViewer.HorizontalAlignment = HorizontalAlignment.Center;
      theViewer.VerticalAlignment = VerticalAlignment.Top;
      theViewer.ImageHorizontalAlignment = HorizontalAlignment.Left;
      theViewer.ImageVerticalAlignment = VerticalAlignment.Top;

      sp.Children.Add(theViewer);

      // Load an image into the viewer
      theViewer.Source = new BitmapImage(new Uri(System.IO.Path.Combine(LEAD_VARS.ImagesDir, "Cannon.jpg")));

      Title = "MagnifyGlassEffect - Click and and move the mouse cursor on the image to see the effect";

      theViewer.PreviewMouseDown += new MouseButtonEventHandler(theViewer_PreviewMouseDown);
      theViewer.MouseMove += new MouseEventHandler(theViewer_MouseMove);
      theViewer.MouseUp += new MouseButtonEventHandler(theViewer_MouseUp);
   }

   private void theViewer_PreviewMouseDown(object sender, MouseButtonEventArgs e)
   {
      MagnifyGlassEffect effect = new MagnifyGlassEffect();

      Point pos = e.GetPosition(theViewer);

      BitmapSource source = theViewer.Source as BitmapSource;
      if(source != null)
      {
         effect.Center = new Point(
            (1.0 * pos.X) / source.PixelWidth,
            (1.0 * pos.Y) / source.PixelHeight);

         effect.Radius = 0.25;
         effect.AspectRatio = 1.0;
         effect.ScaleFactor = 2.0;
         effect.Color = Colors.Blue;
         effect.Border = 1;
         effect.CrossHairs = 1;
         theViewer.ImageEffect = effect;
      }
   }

   private void theViewer_MouseMove(object sender, MouseEventArgs e)
   {
      MagnifyGlassEffect effect = theViewer.ImageEffect as MagnifyGlassEffect;
      if(effect != null)
      {
         Point pos = e.GetPosition(theViewer);

         BitmapSource source = theViewer.Source as BitmapSource;
         if(source != null)
         {
            effect.Center = new Point(
               (1.0 * pos.X) / source.PixelWidth,
               (1.0 * pos.Y) / source.PixelHeight);
         }
      }
   }

   private void theViewer_MouseUp(object sender, MouseButtonEventArgs e)
   {
      if(theViewer.ImageEffect != null)
      {
         theViewer.ImageEffect = null;
      }
   }
}

static class LEAD_VARS
{
public const string ImagesDir = @"C:\Users\Public\Documents\LEADTOOLS Images";
}

using Leadtools;
using Leadtools.Codecs;
using Leadtools.ImageProcessing;
using Leadtools.Windows.Media;
using Leadtools.Windows.Media.Effects;
using Leadtools.Windows.Controls;

class MagnifyGlassEffectExampleWindow : UserControl
{
   private ImageViewer theViewer;
   public MagnifyGlassEffectExampleWindow()
   {
      StackPanel sp = new StackPanel();
      Content = sp;

      theViewer = new ImageViewer();

      theViewer.HorizontalAlignment = HorizontalAlignment.Center;
      theViewer.VerticalAlignment = VerticalAlignment.Top;
      theViewer.ImageHorizontalAlignment = HorizontalAlignment.Left;
      theViewer.ImageVerticalAlignment = VerticalAlignment.Top;

      sp.Children.Add(theViewer);

      // Load an image into the viewer
      theViewer.Source = new BitmapImage(new Uri(LeadtoolsExamples.Common.ImagesPath.Path + "Cannon.jpg"));

      theViewer.MouseMove += new MouseEventHandler(theViewer_MouseMove);
   }

   private void theViewer_PreviewMouseDown(object sender, MouseButtonEventArgs e)
   {
      MagnifyGlassEffect effect = new MagnifyGlassEffect();

      Point pos = e.GetPosition(theViewer);

      BitmapSource source = theViewer.Source as BitmapSource;
      if(source != null)
      {
         effect.Center = new Point(
            (1.0 * pos.X) / source.PixelWidth,
            (1.0 * pos.Y) / source.PixelHeight);

         effect.Radius = 0.25;
         effect.AspectRatio = 1.0;
         effect.ScaleFactor = 2.0;
         effect.Color = Colors.Blue;
         effect.Border = 1;
         effect.CrossHairs = 1;
         theViewer.ImageEffect = effect;
      }
   }

   private void theViewer_MouseMove(object sender, MouseEventArgs e)
   {
      MagnifyGlassEffect effect = theViewer.ImageEffect as MagnifyGlassEffect;
      if(effect != null)
      {
         Point pos = e.GetPosition(theViewer);

         BitmapSource source = theViewer.Source as BitmapSource;
         if(source != null)
         {
            effect.Center = new Point(
               (1.0 * pos.X) / source.PixelWidth,
               (1.0 * pos.Y) / source.PixelHeight);
         }
      }
   }

   private void theViewer_MouseUp(object sender, MouseButtonEventArgs e)
   {
      if(theViewer.ImageEffect != null)
      {
         theViewer.ImageEffect = null;
      }
   }
}

Imports Leadtools
Imports Leadtools.Codecs
Imports Leadtools.ImageProcessing
Imports Leadtools.Windows.Controls
Imports Leadtools.Windows.Media
Imports Leadtools.Windows.Media.Effects

Class MagnifyGlassEffectExampleWindow
   Inherits UserControl
   Private theViewer As ImageViewer
   Public Sub New()
      Dim sp As New StackPanel()
      Content = sp

      theViewer = New ImageViewer()

      theViewer.HorizontalAlignment = HorizontalAlignment.Center
      theViewer.VerticalAlignment = VerticalAlignment.Top
      theViewer.ImageHorizontalAlignment = HorizontalAlignment.Left
      theViewer.ImageVerticalAlignment = VerticalAlignment.Top

      sp.Children.Add(theViewer)

      ' Load an image into the viewer
      theViewer.Source = New BitmapImage(New Uri(LeadtoolsExamples.Common.ImagesPath.Path + "Cannon.jpg"))

      AddHandler theViewer.MouseMove, AddressOf theViewer_MouseMove
   End Sub

   Private Sub theViewer_PreviewMouseDown(ByVal sender As Object, ByVal e As MouseButtonEventArgs)
      Dim effect As New MagnifyGlassEffect()

      Dim pos As Point = e.GetPosition(theViewer)

      Dim source As BitmapSource = DirectCast(theViewer.Source, BitmapSource)
      If Not source Is Nothing Then
         effect.Center = New Point( _
            (1.0 * pos.X) / source.PixelWidth, _
            (1.0 * pos.Y) / source.PixelHeight)

         effect.Radius = 0.25
         effect.AspectRatio = 1.0
         effect.ScaleFactor = 2.0
         effect.Color = Colors.Blue
         effect.Border = 1
         effect.CrossHairs = 1
         theViewer.ImageEffect = effect
      End If
   End Sub

   Private Sub theViewer_MouseMove(ByVal sender As Object, ByVal e As MouseEventArgs)
      Dim effect As MagnifyGlassEffect = DirectCast(theViewer.ImageEffect, MagnifyGlassEffect)
      If Not effect Is Nothing Then
         Dim pos As Point = e.GetPosition(theViewer)

         Dim source As BitmapSource = DirectCast(theViewer.Source, BitmapSource)
         If Not source Is Nothing Then
            effect.Center = New Point( _
               (1.0 * pos.X) / source.PixelWidth, _
               (1.0 * pos.Y) / source.PixelHeight)
         End If
      End If
   End Sub

   Private Sub theViewer_MouseUp(ByVal sender As Object, ByVal e As MouseButtonEventArgs)
      If Not theViewer.ImageEffect Is Nothing Then
         theViewer.ImageEffect = Nothing
      End If
   End Sub
End Class

<Window x:Class="MagnifyGlassEffectExample"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:leadControls="clr-namespace:Leadtools.Windows.Controls;assembly=Leadtools.Windows.Controls"
xmlns:leadEffects="clr-namespace:Leadtools.Windows.Media.Effects;assembly=Leadtools.Windows.Media.Effects"
Height="600" Width="800">
   <StackPanel>
      <leadControls:ImageViewer
            HorizontalAlignment="Center" VerticalAlignment="Top"
            ImageHorizontalAlignment="Left" ImageVerticalAlignment="Top"
            Source="file:///c:\users\Public\Documents\LEADTOOLS Images\cannon.jpg">
         <leadControls:ImageViewer.ImageEffect>
            <leadEffects:MagnifyGlassEffect
               Center="0.5,0.5" Radius="0.25" AspectRatio="1.0" ScaleFactor="2.0"
               Color="Blue" Border="1" CrossHairs="1">
            </leadEffects:MagnifyGlassEffect>
         </leadControls:ImageViewer.ImageEffect>
      </leadControls:ImageViewer>
   </StackPanel>
</Window>

Requirements

Target Platforms

Reference

MagnifyGlassEffect Members
Leadtools.Windows.Media.Effects Namespace
Introduction