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WPF Brushes Overview

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Everything visible on your screen is visible because it was painted by a brush. For example, a brush is used to describe the background of a button, the foreground of text, and the fill of a shape. This topic introduces the concepts of painting with Windows Presentation Foundation (WPF) brushes and provides examples. Brushes enable you to paint user interface (UI) objects with anything from simple, solid colors to complex sets of patterns and images.

  • Painting with a Brush
  • Paint with a Solid Color
  • Paint with a Linear Gradient
  • Paint with a Radial Gradient
  • Paint with an Image
  • Paint with a Drawing
  • Paint with a Visual
  • Paint using Predefined and System Brushes
  • Common Brush Features
  • Related Topics

Painting with a Brush

A Brush "paints" an area with its output. Different brushes have different types of output. Some brushes paint an area with a solid color, others with a gradient, pattern, image, or drawing. The following illustration shows examples of each of the different Brush types.

Brush examples

Brush types

Most visual objects enable you to specify how they are painted. The following table lists some common objects and properties with which you can use a Brush.

Class Brush properties

Border

BorderBrush, Background

Control

Background, Foreground

Panel

Background

Pen

Brush

Shape

Fill, Stroke

TextBlock

Background

The following sections describe the different Brush types and provide an example of each.

Paint with a Solid Color

A SolidColorBrush paints an area with a solid Color. There are a variety of ways to specify the Color of a SolidColorBrush: for example, you can specify its alpha, red, blue, and green channels or use one of the predefined color provided by the Colors class.

The following example uses a SolidColorBrush to paint the Fill of a Rectangle. The following illustration shows the painted rectangle.

A Rectangle painted using a SolidColorBrush

A rectangle painted using a SolidColorBrush

Rectangle exampleRectangle = new Rectangle();
exampleRectangle.Width = 75;
exampleRectangle.Height = 75;

// Create a SolidColorBrush and use it to
// paint the rectangle.
SolidColorBrush myBrush = new SolidColorBrush(Colors.Red);
exampleRectangle.Fill = myBrush;

<Rectangle Width="75" Height="75">
  <Rectangle.Fill>
    <SolidColorBrush Color="Red" />
  </Rectangle.Fill>
</Rectangle>

For more information about the SolidColorBrush class, see the Painting with Solid Colors and Gradients Overview.

Paint with a Linear Gradient

A LinearGradientBrush paints an area with a linear gradient. A linear gradient blends two or more colors across a line, the gradient axis. You use GradientStop objects to specify the colors in the gradient and their positions.

The following example uses a LinearGradientBrush to paint the Fill of a Rectangle. The following illustration shows the painted rectangle.

A Rectangle painted using a LinearGradientBrush

A rectangle painted using a LinearGradientBrush

Rectangle exampleRectangle = new Rectangle();
exampleRectangle.Width = 75;
exampleRectangle.Height = 75;

// Create a LinearGradientBrush and use it to
// paint the rectangle.
LinearGradientBrush myBrush = new LinearGradientBrush();
myBrush.GradientStops.Add(new GradientStop(Colors.Yellow, 0.0));
myBrush.GradientStops.Add(new GradientStop(Colors.Orange, 0.5));
myBrush.GradientStops.Add(new GradientStop(Colors.Red, 1.0));

exampleRectangle.Fill = myBrush;

<Rectangle Width="75" Height="75">
  <Rectangle.Fill>
    <LinearGradientBrush>
      <GradientStop Color="Yellow" Offset="0.0" />
      <GradientStop Color="Orange" Offset="0.5" />
      <GradientStop Color="Red" Offset="1.0" />
    </LinearGradientBrush>
  </Rectangle.Fill>
</Rectangle>

For more information about the LinearGradientBrush class, see the Painting with Solid Colors and Gradients Overview.

Paint with a Radial Gradient

A RadialGradientBrush paints an area with a radial gradient. A radial gradient blends two or more colors across a circle. As with the LinearGradientBrush class, you use GradientStop objects to specify the colors in the gradient and their positions.

The following example uses a RadialGradientBrush to paint the Fill of a Rectangle. The following illustration shows the painted rectangle.

A Rectangle painted using a RadialGradientBrush

A rectangle painted using a RadialGradientBrush

Rectangle exampleRectangle = new Rectangle();
exampleRectangle.Width = 75;
exampleRectangle.Height = 75;

// Create a RadialGradientBrush and use it to
// paint the rectangle.
RadialGradientBrush myBrush = new RadialGradientBrush();
myBrush.GradientOrigin = new Point(0.75, 0.25);
myBrush.GradientStops.Add(new GradientStop(Colors.Yellow, 0.0));
myBrush.GradientStops.Add(new GradientStop(Colors.Orange, 0.5));
myBrush.GradientStops.Add(new GradientStop(Colors.Red, 1.0));

exampleRectangle.Fill = myBrush;

<Rectangle Width="75" Height="75">
  <Rectangle.Fill>
    <RadialGradientBrush GradientOrigin="0.75,0.25">
      <GradientStop Color="Yellow" Offset="0.0" />
      <GradientStop Color="Orange" Offset="0.5" />
      <GradientStop Color="Red" Offset="1.0" />
    </RadialGradientBrush>
  </Rectangle.Fill>
</Rectangle>

For more information about the RadialGradientBrush class, see the Painting with Solid Colors and Gradients Overview.

Paint with an Image

An ImageBrush paints an area with a ImageSource.

The following example uses an ImageBrush to paint the Fill of a Rectangle. The following illustration shows the painted rectangle.

A Rectangle painted using a Image

A Rectangle painted by an ImageBrush

Rectangle exampleRectangle = new Rectangle();
exampleRectangle.Width = 75;
exampleRectangle.Height = 75;

// Create an ImageBrush and use it to
// paint the rectangle.
ImageBrush myBrush = new ImageBrush();
myBrush.ImageSource = 
    new BitmapImage(new Uri(@"sampleImages\pinkcherries.jpg", UriKind.Relative));

exampleRectangle.Fill = myBrush;

<Rectangle Width="75" Height="75">
  <Rectangle.Fill>
    <ImageBrush ImageSource="sampleImages\pinkcherries.jpg"  />
  </Rectangle.Fill>
</Rectangle>

For more information about the ImageBrush class, see the Painting with Images, Drawings, and Visuals.

Paint with a Drawing

A DrawingBrush paints an area with a Drawing. A Drawing can contain shapes, images, text, and media.

The following example uses a DrawingBrush to paint the Fill of a Rectangle. The following illustration shows the painted rectangle.

A Rectangle painted using a DrawingBrush

A rectangle painted using a DrawingBrush

Rectangle exampleRectangle = new Rectangle();
exampleRectangle.Width = 75;
exampleRectangle.Height = 75;

// Create a DrawingBrush and use it to
// paint the rectangle.
DrawingBrush myBrush = new DrawingBrush();

GeometryDrawing backgroundSquare =
    new GeometryDrawing(
        Brushes.White,
        null,
        new RectangleGeometry(new Rect(0, 0, 100, 100)));

GeometryGroup aGeometryGroup = new GeometryGroup();
aGeometryGroup.Children.Add(new RectangleGeometry(new Rect(0, 0, 50, 50)));
aGeometryGroup.Children.Add(new RectangleGeometry(new Rect(50, 50, 50, 50)));

LinearGradientBrush checkerBrush = new LinearGradientBrush();
checkerBrush.GradientStops.Add(new GradientStop(Colors.Black, 0.0));
checkerBrush.GradientStops.Add(new GradientStop(Colors.Gray, 1.0));

GeometryDrawing checkers = new GeometryDrawing(checkerBrush, null, aGeometryGroup);

DrawingGroup checkersDrawingGroup = new DrawingGroup();
checkersDrawingGroup.Children.Add(backgroundSquare);
checkersDrawingGroup.Children.Add(checkers);

myBrush.Drawing = checkersDrawingGroup;
myBrush.Viewport = new Rect(0, 0, 0.25, 0.25);
myBrush.TileMode = TileMode.Tile;

exampleRectangle.Fill = myBrush;

<Rectangle Width="75" Height="75">
  <Rectangle.Fill>
    <DrawingBrush Viewport="0,0,0.25,0.25" TileMode="Tile">
      <DrawingBrush.Drawing>
        <DrawingGroup>
          <GeometryDrawing Brush="White">
            <GeometryDrawing.Geometry>
              <RectangleGeometry Rect="0,0,100,100" />
            </GeometryDrawing.Geometry>
          </GeometryDrawing>

          <GeometryDrawing>
            <GeometryDrawing.Geometry>
              <GeometryGroup>
                <RectangleGeometry Rect="0,0,50,50" />
                <RectangleGeometry Rect="50,50,50,50" />
              </GeometryGroup>
            </GeometryDrawing.Geometry>
            <GeometryDrawing.Brush>
              <LinearGradientBrush>
                <GradientStop Offset="0.0" Color="Black" />
                <GradientStop Offset="1.0" Color="Gray" />
              </LinearGradientBrush>
            </GeometryDrawing.Brush>
          </GeometryDrawing>
        </DrawingGroup>
      </DrawingBrush.Drawing>
    </DrawingBrush>
  </Rectangle.Fill>
</Rectangle>

For more information about the DrawingBrush class, see the Painting with Images, Drawings, and Visuals.

Paint with a Visual

A VisualBrush paints an area with a Visual object. Examples of Visual objects include Button, Page, and MediaElement. A VisualBrush also enables you to project content from one portion of your application into another area; it's very useful for creating reflection effects and magnifying portions of the screen.

The following example uses a VisualBrush to paint the Fill of a Rectangle. The following illustration shows the painted rectangle.

A Rectangle painted using a VisualBrush

A rectangle painted using a VisualBrush

Rectangle exampleRectangle = new Rectangle();
exampleRectangle.Width = 75;
exampleRectangle.Height = 75;

// Create a VisualBrush and use it
// to paint the rectangle.
VisualBrush myBrush = new VisualBrush();

//
// Create the brush's contents.
//
StackPanel aPanel = new StackPanel();

// Create a DrawingBrush and use it to
// paint the panel.
DrawingBrush myDrawingBrushBrush = new DrawingBrush();
GeometryGroup aGeometryGroup = new GeometryGroup();
aGeometryGroup.Children.Add(new RectangleGeometry(new Rect(0, 0, 50, 50)));
aGeometryGroup.Children.Add(new RectangleGeometry(new Rect(50, 50, 50, 50)));
RadialGradientBrush checkerBrush = new RadialGradientBrush();
checkerBrush.GradientStops.Add(new GradientStop(Colors.MediumBlue, 0.0));
checkerBrush.GradientStops.Add(new GradientStop(Colors.White, 1.0));
GeometryDrawing checkers = new GeometryDrawing(checkerBrush, null, aGeometryGroup);
myDrawingBrushBrush.Drawing = checkers;
aPanel.Background = myDrawingBrushBrush;

// Create some text.
TextBlock someText = new TextBlock();
someText.Text = "Hello, World";
FontSizeConverter fSizeConverter = new FontSizeConverter();
someText.FontSize = (double)fSizeConverter.ConvertFromString("10pt");
someText.Margin = new Thickness(10);

aPanel.Children.Add(someText);

myBrush.Visual = aPanel;
exampleRectangle.Fill = myBrush;

<Rectangle Width="75" Height="75">
  <Rectangle.Fill>
    <VisualBrush TileMode="Tile">
      <VisualBrush.Visual>
        <StackPanel>
          <StackPanel.Background>
            <DrawingBrush>
              <DrawingBrush.Drawing>
                <GeometryDrawing>
                  <GeometryDrawing.Brush>
                    <RadialGradientBrush>
                      <GradientStop Color="MediumBlue" Offset="0.0" />
                      <GradientStop Color="White" Offset="1.0" />
                    </RadialGradientBrush>
                  </GeometryDrawing.Brush>
                  <GeometryDrawing.Geometry>
                    <GeometryGroup>
                      <RectangleGeometry Rect="0,0,50,50" />
                      <RectangleGeometry Rect="50,50,50,50" />
                    </GeometryGroup>
                  </GeometryDrawing.Geometry>
                </GeometryDrawing>
              </DrawingBrush.Drawing>
            </DrawingBrush>
          </StackPanel.Background>
          <TextBlock FontSize="10pt" Margin="10">Hello, World!</TextBlock>
        </StackPanel>
      </VisualBrush.Visual>
    </VisualBrush>
  </Rectangle.Fill>
</Rectangle>

For more information about the VisualBrush class, see the Painting with Images, Drawings, and Visuals.

Paint using Predefined and System Brushes

For convenience, Windows Presentation Foundation (WPF) provides a set of predefined and system brushes that you can use to paint objects.

Common Brush Features

Brush objects provide an Opacity property that can be used to make a brush transparent or partially transparent. An Opacity value of 0 makes a brush completely transparent, while an Opacity value of 1 makes a brush completely opaque. The following example uses the Opacity property to make a SolidColorBrush 25 percent opaque.

<Rectangle Width="100" Height="100">
  <Rectangle.Fill>
    <SolidColorBrush Color="Blue" Opacity="0.25" />
  </Rectangle.Fill>
</Rectangle>

Rectangle myRectangle = new Rectangle();
myRectangle.Width = 100;
myRectangle.Height = 100;
SolidColorBrush partiallyTransparentSolidColorBrush
    = new SolidColorBrush(Colors.Blue);
partiallyTransparentSolidColorBrush.Opacity = 0.25;
myRectangle.Fill = partiallyTransparentSolidColorBrush;

If the brush contains colors that are partially transparent, the opacity value of the color is combined through multiplication with the opacity value of the brush. For example, if a brush has an opacity value of 0.5 and a color used in the brush also has an opacity value of 0.5, the output color has an opacity value of 0.25.

NoteNote:

It's more efficient to change the opacity value of a brush than it is to change the opacity of an entire element using its UIElement.Opacity property.

You can rotate, scale, skew, and translate a brush's content by using its Transform or RelativeTransform properties. For more information, see the Brush Transformation Overview.

Because they are Animatable objects, Brush objects can be animated. For more information, see the Animation Overview.

Freezable Features

Because it inherits from the Freezable class, the Brush class provides several special features: Brush objects can be declared as Resources Overview, shared among multiple objects, and cloned. In addition, all the Brush types except VisualBrush can be made read-only to improve performance and made thread-safe.

For more information about the different features provided by Freezable objects, see the Freezable Objects Overview.

For more information on why VisualBrush objects cannot be frozen, see the VisualBrush type page.

See Also

Reference

Brush
Brushes

Concepts

Painting with Solid Colors and Gradients Overview
Painting with Images, Drawings, and Visuals
Freezable Objects Overview

Other Resources

Brushes Sample
ImageBrush Sample
DrawingBrush Sample
VisualBrush Sample
Brushes How-to Topics