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DrawingContext.PushEffect(BitmapEffect, BitmapEffectInput) Method

Definition

Caution

BitmapEffects are deprecated and no longer function. Consider using Effects where appropriate instead.

Pushes the specified BitmapEffect onto the drawing context.

public:
 abstract void PushEffect(System::Windows::Media::Effects::BitmapEffect ^ effect, System::Windows::Media::Effects::BitmapEffectInput ^ effectInput);
public abstract void PushEffect (System.Windows.Media.Effects.BitmapEffect effect, System.Windows.Media.Effects.BitmapEffectInput effectInput);
[System.Obsolete("BitmapEffects are deprecated and no longer function.  Consider using Effects where appropriate instead.")]
public abstract void PushEffect (System.Windows.Media.Effects.BitmapEffect effect, System.Windows.Media.Effects.BitmapEffectInput effectInput);
abstract member PushEffect : System.Windows.Media.Effects.BitmapEffect * System.Windows.Media.Effects.BitmapEffectInput -> unit
[<System.Obsolete("BitmapEffects are deprecated and no longer function.  Consider using Effects where appropriate instead.")>]
abstract member PushEffect : System.Windows.Media.Effects.BitmapEffect * System.Windows.Media.Effects.BitmapEffectInput -> unit
Public MustOverride Sub PushEffect (effect As BitmapEffect, effectInput As BitmapEffectInput)

Parameters

effect
BitmapEffect

The effect to apply to subsequent drawings.

effectInput
BitmapEffectInput

The area to which the effect is applied, or null if the effect is to be applied to the entire area of subsequent drawings.

Attributes

Examples

The following example demonstrates the PushOpacity, PushEffect, and Pop commands.

using System;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Media;
using System.Windows.Media.Animation;
using System.Windows.Navigation;
using System.Windows.Media.Effects;

namespace SDKSample
{

    public class PushEffectExample : Page
    {

        public PushEffectExample()
        {
            Pen shapeOutlinePen = new Pen(Brushes.Black, 2);
            shapeOutlinePen.Freeze();

            // Create a DrawingGroup
            DrawingGroup dGroup = new DrawingGroup();

            // Obtain a DrawingContext from 
            // the DrawingGroup.
            using (DrawingContext dc = dGroup.Open())
            {
                // Draw a rectangle at full opacity.
                dc.DrawRectangle(Brushes.Blue, shapeOutlinePen, new Rect(0, 0, 25, 25));

                // Push an opacity change of 0.5. 
                // The opacity of each subsequent drawing will
                // will be multiplied by 0.5.
                dc.PushOpacity(0.5);

                // This rectangle is drawn at 50% opacity.
                dc.DrawRectangle(Brushes.Blue, shapeOutlinePen, new Rect(25, 25, 25, 25));

                // Blurs subsquent drawings. 
                dc.PushEffect(new BlurBitmapEffect(), null);

                // This rectangle is blurred and drawn at 50% opacity (0.5 x 0.5). 
                dc.DrawRectangle(Brushes.Blue, shapeOutlinePen, new Rect(50, 50, 25, 25));

                // This rectangle is also blurred and drawn at 50% opacity.
                dc.DrawRectangle(Brushes.Blue, shapeOutlinePen, new Rect(75, 75, 25, 25));

                // Stop applying the blur to subsquent drawings.
                dc.Pop();

                // This rectangle is drawn at 50% opacity with no blur effect.
                dc.DrawRectangle(Brushes.Blue, shapeOutlinePen, new Rect(100, 100, 25, 25));
            }

            // Display the drawing using an image control.
            Image theImage = new Image();
            DrawingImage dImageSource = new DrawingImage(dGroup);
            theImage.Source = dImageSource;

            this.Content = theImage;
        }
    }
}
Imports System.Windows.Media.Animation
Imports System.Windows.Media.Effects

Namespace SDKSample


    Public Class PushEffectExample
        Inherits Page

        Public Sub New()
            Dim shapeOutlinePen As New Pen(Brushes.Black, 2)
            shapeOutlinePen.Freeze()

            ' Create a DrawingGroup
            Dim dGroup As New DrawingGroup()

            ' Obtain a DrawingContext from 
            ' the DrawingGroup.
            Using dc As DrawingContext = dGroup.Open()
                ' Draw a rectangle at full opacity.
                dc.DrawRectangle(Brushes.Blue, shapeOutlinePen, New Rect(0, 0, 25, 25))

                ' Push an opacity change of 0.5. 
                ' The opacity of each subsequent drawing will
                ' will be multiplied by 0.5.
                dc.PushOpacity(0.5)

                ' This rectangle is drawn at 50% opacity.
                dc.DrawRectangle(Brushes.Blue, shapeOutlinePen, New Rect(25, 25, 25, 25))

                ' Blurs subsquent drawings. 
                dc.PushEffect(New BlurBitmapEffect(), Nothing)

                ' This rectangle is blurred and drawn at 50% opacity (0.5 x 0.5). 
                dc.DrawRectangle(Brushes.Blue, shapeOutlinePen, New Rect(50, 50, 25, 25))

                ' This rectangle is also blurred and drawn at 50% opacity.
                dc.DrawRectangle(Brushes.Blue, shapeOutlinePen, New Rect(75, 75, 25, 25))

                ' Stop applying the blur to subsquent drawings.
                dc.Pop()

                ' This rectangle is drawn at 50% opacity with no blur effect.
                dc.DrawRectangle(Brushes.Blue, shapeOutlinePen, New Rect(100, 100, 25, 25))
            End Using

            ' Display the drawing using an image control.
            Dim theImage As New Image()
            Dim dImageSource As New DrawingImage(dGroup)
            theImage.Source = dImageSource

            Me.Content = theImage

        End Sub




    End Class

End Namespace

Remarks

The effect is applied to all subsequent drawing operations until it is removed by the Pop command.

Applies to