DrawingGroup.BitmapEffect Vlastnost

Definice

Obor názvů:

System.Windows.Media

Sestavení:

PresentationCore.dll

Získá nebo nastaví BitmapEffect , aby se na to DrawingGroupvztahuje .

public:
 property System::Windows::Media::Effects::BitmapEffect ^ BitmapEffect { System::Windows::Media::Effects::BitmapEffect ^ get(); void set(System::Windows::Media::Effects::BitmapEffect ^ value); };

public System.Windows.Media.Effects.BitmapEffect BitmapEffect { get; set; }

member this.BitmapEffect : System.Windows.Media.Effects.BitmapEffect with get, set

Public Property BitmapEffect As BitmapEffect

Hodnota vlastnosti

BitmapEffect

Platí BitmapEffect pro to DrawingGroup. Výchozí formát je null.

Příklady

Tento příklad ukazuje, jak použít BitmapEffect na výkres. BitmapEffect K rozostření nebo embosům použijte jiné vizuální efekty k vykreslení obsahu.

Rastrové efekty podporují pouze DrawingGroup objekty. Chcete-li použít rastrový efekt na jiný typ objektu Drawing , přidejte ho do DrawingGroup a nastavte BitmapEffect vlastnost objektu DrawingGroup .

Poznámka

Windows Presentation Foundation rastrové efekty jsou vykresleny softwarem. Jakýkoli objekt, který použije, BitmapEffect se také vykresluje v softwaru. BitmapEffect Nepoužívejte velké vizuály nebo animace, protože tento scénář může způsobit snížení výkonu systému.

Následující příklad používá DrawingGroup k použití na BlurBitmapEffect několik GeometryDrawing objektů.

Následující obrázek znázorňuje výstup z tohoto příkladu.

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

namespace SDKSample 
{

    /// <summary>
    /// This example creates two DrawingGroup objects,
    /// one with a bitmap effect and one without.
    /// </summary>
    public class BitmapEffectExample : Page
    {
        public BitmapEffectExample()
        {

            //
            // Create a DrawingGroup
            // that has no BitmapEffect
            //
            PathFigure pLineFigure = new PathFigure();
            pLineFigure.StartPoint = new Point(25, 25);
            PolyLineSegment pLineSegment = new PolyLineSegment();
            pLineSegment.Points.Add(new Point(0,50));
            pLineSegment.Points.Add(new Point(25, 75));
            pLineSegment.Points.Add(new Point(50, 50));
            pLineSegment.Points.Add(new Point(25, 25));
            pLineSegment.Points.Add(new Point(25, 0));
            pLineFigure.Segments.Add(pLineSegment);
            PathGeometry pGeometry = new PathGeometry();
            pGeometry.Figures.Add(pLineFigure);
          
            GeometryDrawing drawing1 = new GeometryDrawing(
                    Brushes.Lime, 
                    new Pen(Brushes.Black, 10),
                    pGeometry
                );

            GeometryDrawing drawing2 = new GeometryDrawing(
                    Brushes.Lime,
                    new Pen(Brushes.Black, 2),
                    new EllipseGeometry(new Point(10,10), 5, 5)
                );
            
            // Create a DrawingGroup
            DrawingGroup drawingGroupWithoutBitmapEffect = new DrawingGroup();
            drawingGroupWithoutBitmapEffect.Children.Add(drawing1);
            drawingGroupWithoutBitmapEffect.Children.Add(drawing2);

            // Use an Image control and a DrawingImage to
            // display the drawing.
            DrawingImage drawingImage01 = new DrawingImage(drawingGroupWithoutBitmapEffect);
            
            // Freeze the DrawingImage for performance benefits.
            drawingImage01.Freeze();

            Image image01 = new Image();
            image01.Source = drawingImage01;
            image01.Stretch = Stretch.None;
            image01.HorizontalAlignment = HorizontalAlignment.Left;

            //
            // Create another DrawingGroup and apply 
            // a blur effect to it.
            //

            // Create a clone of the first DrawingGroup.
            DrawingGroup drawingGroupWithBitmapEffect = 
                drawingGroupWithoutBitmapEffect.Clone();

            // Create a blur effect.
            BlurBitmapEffect blurEffect = new BlurBitmapEffect();
            blurEffect.Radius = 3.0;

            // Apply it to the drawing group.
            drawingGroupWithBitmapEffect.BitmapEffect = blurEffect;

            // Use another Image control and DrawingImage
            // to display the drawing.
            DrawingImage drawingImage02 = new DrawingImage(drawingGroupWithBitmapEffect);
            
            // Freeze the DrawingImage for performance benefits.
            drawingImage02.Freeze();

            Image image02 = new Image();
            image02.Source = drawingImage02;
            image02.Stretch = Stretch.None;
            image02.HorizontalAlignment = HorizontalAlignment.Left;

            // Create borders around the images and add them to the
            // page.
            Border border01 = new Border();
            border01.BorderBrush = Brushes.Gray;
            border01.BorderThickness = new Thickness(1);
            border01.VerticalAlignment = VerticalAlignment.Top;
            border01.Margin = new Thickness(10);
            border01.Child = image01;

            Border border02 = new Border();
            border02.BorderBrush = Brushes.Gray;
            border02.BorderThickness = new Thickness(1);
            border02.VerticalAlignment = VerticalAlignment.Top;
            border02.Margin = new Thickness(50,10,10,10);
            border02.Child = image02;

            StackPanel mainPanel = new StackPanel();
            mainPanel.Orientation = Orientation.Horizontal;
            mainPanel.HorizontalAlignment = HorizontalAlignment.Left;
            mainPanel.VerticalAlignment = VerticalAlignment.Top;
            mainPanel.Children.Add(border01);
            mainPanel.Children.Add(border02);

            //
            // Use a DrawingBrush to create a checkered background for the page.
            //
            GeometryDrawing backgroundSquareDrawing = 
                new GeometryDrawing(
                    Brushes.White,
                    null,
                    new RectangleGeometry(new Rect(0,0,1,1)));
            GeometryGroup twoRectangles = new GeometryGroup();
            twoRectangles.Children.Add(new RectangleGeometry(new Rect(0,0,0.5,0.5)));
            twoRectangles.Children.Add(new RectangleGeometry(new Rect(0.5,0.5,0.5,0.5)));
            SolidColorBrush squaresBrush = 
                new SolidColorBrush(Color.FromArgb(102,204,204,204));
            squaresBrush.Opacity = 0.4;
            GeometryDrawing checkerDrawing = 
                new GeometryDrawing(
                    squaresBrush,
                    null,
                    twoRectangles);
            DrawingGroup checkerDrawings = new DrawingGroup();
            checkerDrawings.Children.Add(backgroundSquareDrawing);
            checkerDrawings.Children.Add(checkerDrawing);
            DrawingBrush checkerBrush = new DrawingBrush(checkerDrawings);
            checkerBrush.Viewport = new Rect(0,0,10,10);
            checkerBrush.ViewportUnits = BrushMappingMode.Absolute;
            checkerBrush.TileMode = TileMode.Tile;
            checkerBrush.Freeze();

            this.Background = checkerBrush;
            this.Content = mainPanel;
        }
    }
}

<Page 
  xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
  xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
  xmlns:PresentationOptions="http://schemas.microsoft.com/winfx/2006/xaml/presentation/options" 
  xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
  mc:Ignorable="PresentationOptions">

  <StackPanel Margin="20" Orientation="Horizontal" 
    HorizontalAlignment="Left" VerticalAlignment="Top">

    <!-- Shows the DrawingGroup without the blur effect. -->
    <Border BorderBrush="Gray" BorderThickness="1"  Margin="10"
      VerticalAlignment="Top">
      <Image Stretch="None" HorizontalAlignment="Left">
        <Image.Source>
          <DrawingImage PresentationOptions:Freeze="True">
            <DrawingImage.Drawing>
              <DrawingGroup>
                <GeometryDrawing Brush="Lime" Geometry="M 25,25 L 0,50 25,75 50,50 25,25 25,0">
                  <GeometryDrawing.Pen>
                    <Pen Thickness="10" Brush="Black" />
                  </GeometryDrawing.Pen>
                </GeometryDrawing>
                <GeometryDrawing Brush="Lime">
                  <GeometryDrawing.Geometry>
                    <EllipseGeometry Center="10,10" RadiusX="5" RadiusY="5" />
                  </GeometryDrawing.Geometry>
                  <GeometryDrawing.Pen>
                    <Pen Thickness="2" Brush="Black" />
                  </GeometryDrawing.Pen>
                </GeometryDrawing>
              </DrawingGroup>
            </DrawingImage.Drawing>
          </DrawingImage>
        </Image.Source>
      </Image>
    </Border>

    <Border BorderBrush="Gray" BorderThickness="1" Margin="50,10,10,10"
      VerticalAlignment="Top">
      <Image Stretch="None" HorizontalAlignment="Left">
        <Image.Source>
          <DrawingImage PresentationOptions:Freeze="True">
            <DrawingImage.Drawing>

              <!-- The drawing group, with a BlurBitmapEffect. -->
              <DrawingGroup>
                <GeometryDrawing Brush="Lime" Geometry="M 25,25 L 0,50 25,75 50,50 25,25 25,0">
                  <GeometryDrawing.Pen>
                    <Pen Thickness="10" Brush="Black" />
                  </GeometryDrawing.Pen>
                </GeometryDrawing>
                <GeometryDrawing Brush="Lime">
                  <GeometryDrawing.Geometry>
                    <EllipseGeometry Center="10,10" RadiusX="5" RadiusY="5" />
                  </GeometryDrawing.Geometry>
                  <GeometryDrawing.Pen>
                    <Pen Thickness="2" Brush="Black" />
                  </GeometryDrawing.Pen>
                </GeometryDrawing>

                <DrawingGroup.BitmapEffect>
                  <BlurBitmapEffect Radius="5"  />
                </DrawingGroup.BitmapEffect>
              </DrawingGroup>
            </DrawingImage.Drawing>
          </DrawingImage>
        </Image.Source>
      </Image>
    </Border>
  </StackPanel>

  <Page.Background>

    <!-- Creates a checkered background. -->
    <DrawingBrush Viewport="0,0,10,10" ViewportUnits="Absolute" TileMode="Tile"
      PresentationOptions:Freeze="True">
      <DrawingBrush.Drawing>
        <DrawingGroup>
          <GeometryDrawing Brush="White">
            <GeometryDrawing.Geometry>
              <RectangleGeometry Rect="0 0 1 1"/>
            </GeometryDrawing.Geometry>
          </GeometryDrawing>
          <GeometryDrawing Brush="#66CCCCCC">
            <GeometryDrawing.Geometry>
              <GeometryGroup>
                <RectangleGeometry Rect="0 0 0.5 0.5" />
                <RectangleGeometry Rect="0.5 0.5 0.5 0.5"/>
              </GeometryGroup>
            </GeometryDrawing.Geometry>
          </GeometryDrawing>
        </DrawingGroup>
      </DrawingBrush.Drawing>
    </DrawingBrush>
  </Page.Background>
</Page>

Poznámky

Další informace o rastrových efektech a jejich fungování najdete v tématu Přehled rastrových efektů.

DrawingGroup operace se použijí v následujícím pořadí:

• OpacityMask

• Opacity

• BitmapEffect

• ClipGeometry

• Transform

Informace o vlastnosti závislosti

Pole identifikátoru	BitmapEffectProperty
Vlastnosti metadat nastavené na true	Žádné