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BitmapCacheBrush Class

Paints an area with cached content.

Namespace:  System.Windows.Media
Assembly:  PresentationCore (in PresentationCore.dll)
XMLNS for XAML: http://schemas.microsoft.com/winfx/2006/xaml/presentation, http://schemas.microsoft.com/netfx/2007/xaml/presentation
public sealed class BitmapCacheBrush : Brush
<BitmapCacheBrush .../>

Use the BitmapCacheBrush class to reuse a cached element efficiently. This is useful when you need to paint complex content onto multiple elements. Use the BitmapCache class to cache a complex element.

Assign a Visual to the Target property and optionally assign a BitmapCache to the BitmapCache property. The CacheMode of the brush and the target Visual interact to produce different behaviors. The following table describes this interaction.

Target has no CacheMode

Target has CacheMode

Brush has no CacheMode

Target visual renders normally; brush uses default cache behavior.

Target visual renders into its own cache; brush uses target’s cache when rendering.

Brush has CacheMode

Target visual renders normally; brush renders target into its own cache and uses this to render.

Target visual renders into its own cache; brush renders target into brush's own cache and uses this to render.

The BitmapCacheBrush class is similar to the VisualBrush class, but BitmapCacheBrush always renders from a cache on the target element, or from a cache defined by the BitmapCache property. The BitmapCacheBrush class also supports dirty regions.

The following table shows the default bitmap cache settings for the BitmapCacheBrush class.

Bitmap Cache Property

Default Setting

SnapsToDevicePixels

false

EnableClearType

false

RenderAtScale

1

The SnapsToDevicePixels property is ignored by the BitmapCacheBrush class.

The BitmapCacheBrush class ignores the following properties on the root Visual. This behavior differs from the VisualBrush class.

The following code example shows how to associate a BitmapCache with a BitmapCacheBrush. You can use the BitmapCacheBrush resource on multiple elements and achieve good performance. For the complete code listing, see How to: Use a Cached Element as a Brush.


<Window.Resources>
    <RichTextBox x:Key="cachedRichTextBox"  >
        <RichTextBox.CacheMode>
            <BitmapCache EnableClearType="True" RenderAtScale="1" SnapsToDevicePixels="True" />
        </RichTextBox.CacheMode>
    </RichTextBox>

    <BitmapCacheBrush x:Key="cachedRichTextBoxBrush" Target="{StaticResource cachedRichTextBox}">
        <BitmapCacheBrush.BitmapCache>
            <BitmapCache EnableClearType="False" RenderAtScale="0.4" SnapsToDevicePixels="False" />
        </BitmapCacheBrush.BitmapCache>
    </BitmapCacheBrush>        
</Window.Resources>


Any public static (Shared in Visual Basic) members of this type are thread safe. Any instance members are not guaranteed to be thread safe.

Windows 7, Windows Vista SP1 or later, Windows XP SP3, Windows Server 2008 (Server Core Role not supported), Windows Server 2008 R2 (Server Core Role not supported), Windows Server 2003 SP2

The .NET Framework does not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.

.NET Framework

Supported in: 4

.NET Framework Client Profile

Supported in: 4
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