HOW TO：建立複合圖形

更新：2007 年 11 月

本範例示範如何使用 DrawingGroup，將多個 Drawing 物件合併到單一複合繪圖，以建立複雜的繪圖。

範例

下列範例會使用 DrawingGroup，從 GeometryDrawing 和 ImageDrawing 物件建立複合繪圖。下圖顯示的是這個範例產生的輸出。

使用 DrawingGroup 建立的複合繪圖

包含多個圖形的 DrawingGroup

請注意灰色框線，這是繪圖的界限。

//
// Create three drawings.
//
GeometryDrawing ellipseDrawing =
    new GeometryDrawing(
        new SolidColorBrush(Color.FromArgb(102, 181, 243, 20)),
        new Pen(Brushes.Black, 4),
        new EllipseGeometry(new Point(50,50), 50, 50)
    );

ImageDrawing kiwiPictureDrawing = 
    new ImageDrawing(
        new BitmapImage(new Uri(@"sampleImages\kiwi.png", UriKind.Relative)), 
        new Rect(50,50,100,100));

GeometryDrawing ellipseDrawing2 =
    new GeometryDrawing(
        new SolidColorBrush(Color.FromArgb(102,181,243,20)),
        new Pen(Brushes.Black, 4),
        new EllipseGeometry(new Point(150, 150), 50, 50)
    );

// Create a DrawingGroup to contain the drawings.
DrawingGroup aDrawingGroup = new DrawingGroup();
aDrawingGroup.Children.Add(ellipseDrawing);
aDrawingGroup.Children.Add(kiwiPictureDrawing);
aDrawingGroup.Children.Add(ellipseDrawing2);

<DrawingGroup>

  <GeometryDrawing Brush="#66B5F314">
    <GeometryDrawing.Geometry>
      <EllipseGeometry Center="50,50" RadiusX="50"  RadiusY="50"/>
    </GeometryDrawing.Geometry>
    <GeometryDrawing.Pen>
      <Pen Brush="Black" Thickness="4" />
    </GeometryDrawing.Pen>
  </GeometryDrawing>
  <ImageDrawing ImageSource="sampleImages\kiwi.png" Rect="50,50,100,100"/>
  <GeometryDrawing Brush="#66B5F314">
    <GeometryDrawing.Geometry>
      <EllipseGeometry Center="150,150" RadiusX="50"  RadiusY="50"/>
    </GeometryDrawing.Geometry>
    <GeometryDrawing.Pen>
      <Pen Brush="Black" Thickness="4" />
    </GeometryDrawing.Pen>
  </GeometryDrawing>
</DrawingGroup>

您可以使用 DrawingGroup，將 Transform、Opacity 設定、OpacityMask、BitmapEffect、ClipGeometry 或 GuidelineSet 套用到它所包含的繪圖。由於 DrawingGroup 也是 Drawing，因此可以包含其他 DrawingGroup 物件。

下列範例與上面範例類似，不同的是它使用了更多的 DrawingGroup 物件，將點陣圖效果和不透明遮罩套用到部分繪圖。下圖顯示的是這個範例產生的輸出。

有多個 DrawingGroup 物件的複合繪圖

包含多個圖形的 DrawingGroup

請注意灰色框線，這是繪圖的界限。

// Create a DrawingGroup.
DrawingGroup mainGroup = new DrawingGroup();

//
// Create a GeometryDrawing
//
GeometryDrawing ellipseDrawing =
    new GeometryDrawing(
        new SolidColorBrush(Color.FromArgb(102, 181, 243, 20)),
        new Pen(Brushes.Black, 4),
        new EllipseGeometry(new Point(50, 50), 50, 50)
    );

//
// Use a DrawingGroup to apply a blur
// bitmap effect to the drawing.
//
DrawingGroup blurGroup = new DrawingGroup();
blurGroup.Children.Add(ellipseDrawing);
BlurBitmapEffect blurEffect = new BlurBitmapEffect();
blurEffect.Radius = 5;
blurGroup.BitmapEffect = blurEffect;

// Add the DrawingGroup to the main DrawingGroup.
mainGroup.Children.Add(blurGroup);

//
// Create an ImageDrawing.
// 
ImageDrawing kiwiPictureDrawing =
    new ImageDrawing(
        new BitmapImage(new Uri(@"sampleImages\kiwi.png", UriKind.Relative)),
        new Rect(50, 50, 100, 100));

//
// Use a DrawingGroup to apply an opacity mask
// and a bevel.
//
DrawingGroup maskedAndBeveledGroup = new DrawingGroup();
maskedAndBeveledGroup.Children.Add(kiwiPictureDrawing);

// Create an opacity mask.
RadialGradientBrush rgBrush =new RadialGradientBrush();
rgBrush.GradientStops.Add(new GradientStop(Color.FromArgb(0,0,0,0), 0.55));
rgBrush.GradientStops.Add(new GradientStop(Color.FromArgb(255,0,0,0), 0.65));
rgBrush.GradientStops.Add(new GradientStop(Color.FromArgb(0,0,0,0), 0.75));
rgBrush.GradientStops.Add(new GradientStop(Color.FromArgb(255,0,0,0), 0.80));
rgBrush.GradientStops.Add(new GradientStop(Color.FromArgb(0,0,0,0), 0.90));
rgBrush.GradientStops.Add(new GradientStop(Color.FromArgb(255,0,0,0), 1.0));
maskedAndBeveledGroup.OpacityMask = rgBrush;

// Apply a bevel.
maskedAndBeveledGroup.BitmapEffect = new BevelBitmapEffect();

// Add the DrawingGroup to the main group.
mainGroup.Children.Add(maskedAndBeveledGroup);

//
// Create another GeometryDrawing.
//
GeometryDrawing ellipseDrawing2 =
  new GeometryDrawing(
      new SolidColorBrush(Color.FromArgb(102, 181, 243, 20)),
      new Pen(Brushes.Black, 4),
      new EllipseGeometry(new Point(150, 150), 50, 50)
  );

// Add the DrawingGroup to the main group.
mainGroup.Children.Add(ellipseDrawing2);

<DrawingGroup>

  <DrawingGroup>
    <GeometryDrawing Brush="#66B5F314">
      <GeometryDrawing.Geometry>
        <EllipseGeometry Center="50,50" RadiusX="50"  RadiusY="50"/>
      </GeometryDrawing.Geometry>
      <GeometryDrawing.Pen>
        <Pen Brush="Black" Thickness="4" />
      </GeometryDrawing.Pen>
    </GeometryDrawing>
    <DrawingGroup.BitmapEffect>
      <BlurBitmapEffect Radius="5" />
    </DrawingGroup.BitmapEffect>
  </DrawingGroup>

  <DrawingGroup>
    <ImageDrawing ImageSource="sampleImages\kiwi.png" Rect="50,50,100,100"/>
    <DrawingGroup.BitmapEffect>
      <BevelBitmapEffect  />
    </DrawingGroup.BitmapEffect>
    <DrawingGroup.OpacityMask>
      <RadialGradientBrush>
        <GradientStop Offset="0.55" Color="#00000000" />
        <GradientStop Offset="0.65" Color="#FF000000" />
        <GradientStop Offset="0.75" Color="#00000000" />
        <GradientStop Offset="0.80" Color="#FF000000" />
        <GradientStop Offset="0.90" Color="#00000000" />
        <GradientStop Offset="1.0" Color="#FF000000" />
      </RadialGradientBrush>
    </DrawingGroup.OpacityMask>
  </DrawingGroup>

  <GeometryDrawing Brush="#66B5F314">
    <GeometryDrawing.Geometry>
      <EllipseGeometry Center="150,150" RadiusX="50"  RadiusY="50"/>
    </GeometryDrawing.Geometry>
    <GeometryDrawing.Pen>
      <Pen Brush="Black" Thickness="4" />
    </GeometryDrawing.Pen>
  </GeometryDrawing>

</DrawingGroup>

如需 Drawing 物件的詳細資訊，請參閱繪圖物件概觀。