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BitmapCacheBrush Class

Definition

Paints an area with cached content.

public ref class BitmapCacheBrush sealed : System::Windows::Media::Brush
public sealed class BitmapCacheBrush : System.Windows.Media.Brush
type BitmapCacheBrush = class
    inherit Brush
Public NotInheritable Class BitmapCacheBrush
Inherits Brush
Inheritance

Examples

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>

Remarks

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.

Constructors

BitmapCacheBrush()

Initializes a new instance of the BitmapCacheBrush class.

BitmapCacheBrush(Visual)

Initializes a new instance of the BitmapCacheBrush class with the specified Visual.

Fields

AutoLayoutContentProperty

Identifies the AutoLayoutContent dependency property.

BitmapCacheProperty

Identifies the BitmapCache dependency property.

TargetProperty

Identifies the Target dependency property.

Properties

AutoLayoutContent

Gets or sets a value that indicates whether layout is applied to the contents of this brush.

BitmapCache

Gets or sets a CacheMode that represents cached content.

CanFreeze

Gets a value that indicates whether the object can be made unmodifiable.

(Inherited from Freezable)
DependencyObjectType

Gets the DependencyObjectType that wraps the CLR type of this instance.

(Inherited from DependencyObject)
Dispatcher

Gets the Dispatcher this DispatcherObject is associated with.

(Inherited from DispatcherObject)
HasAnimatedProperties

Gets a value that indicates whether one or more AnimationClock objects is associated with any of this object's dependency properties.

(Inherited from Animatable)
IsFrozen

Gets a value that indicates whether the object is currently modifiable.

(Inherited from Freezable)
IsSealed

Gets a value that indicates whether this instance is currently sealed (read-only).

(Inherited from DependencyObject)
Opacity

Gets or sets the degree of opacity of a Brush.

(Inherited from Brush)
RelativeTransform

Gets or sets the transformation that is applied to the brush using relative coordinates.

(Inherited from Brush)
Target

Gets or sets the target visual to cache.

Transform

Gets or sets the transformation that is applied to the brush. This transformation is applied after the brush's output has been mapped and positioned.

(Inherited from Brush)

Methods

ApplyAnimationClock(DependencyProperty, AnimationClock, HandoffBehavior)

Applies an AnimationClock to the specified DependencyProperty. If the property is already animated, the specified HandoffBehavior is used.

(Inherited from Animatable)
ApplyAnimationClock(DependencyProperty, AnimationClock)

Applies an AnimationClock to the specified DependencyProperty. If the property is already animated, the SnapshotAndReplace handoff behavior is used.

(Inherited from Animatable)
BeginAnimation(DependencyProperty, AnimationTimeline, HandoffBehavior)

Applies an animation to the specified DependencyProperty. The animation is started when the next frame is rendered. If the specified property is already animated, the specified HandoffBehavior is used.

(Inherited from Animatable)
BeginAnimation(DependencyProperty, AnimationTimeline)

Applies an animation to the specified DependencyProperty. The animation is started when the next frame is rendered. If the specified property is already animated, the SnapshotAndReplace handoff behavior is used.

(Inherited from Animatable)
CheckAccess()

Determines whether the calling thread has access to this DispatcherObject.

(Inherited from DispatcherObject)
ClearValue(DependencyProperty)

Clears the local value of a property. The property to be cleared is specified by a DependencyProperty identifier.

(Inherited from DependencyObject)
ClearValue(DependencyPropertyKey)

Clears the local value of a read-only property. The property to be cleared is specified by a DependencyPropertyKey.

(Inherited from DependencyObject)
Clone()

Creates a modifiable clone of the BitmapCacheBrush, making deep copies of the object's values. When copying the object's dependency properties, this method copies expressions (which might no longer resolve) but not animations or their current values.

CloneCore(Freezable)

Makes the instance a clone (deep copy) of the specified Freezable using base (non-animated) property values.

(Inherited from Freezable)
CloneCurrentValue()

Creates a modifiable clone (deep copy) of the BitmapCacheBrush using its current values.

CloneCurrentValueCore(Freezable)

Makes the instance a modifiable clone (deep copy) of the specified Freezable using current property values.

(Inherited from Freezable)
CoerceValue(DependencyProperty)

Coerces the value of the specified dependency property. This is accomplished by invoking any CoerceValueCallback function specified in property metadata for the dependency property as it exists on the calling DependencyObject.

(Inherited from DependencyObject)
CreateInstance()

Initializes a new instance of the Freezable class.

(Inherited from Freezable)
CreateInstanceCore()

When implemented in a derived class, creates a new instance of the Freezable derived class.

(Inherited from Freezable)
Equals(Object)

Determines whether a provided DependencyObject is equivalent to the current DependencyObject.

(Inherited from DependencyObject)
Freeze()

Makes the current object unmodifiable and sets its IsFrozen property to true.

(Inherited from Freezable)
FreezeCore(Boolean)

Makes this Animatable object unmodifiable or determines whether it can be made unmodifiable.

(Inherited from Animatable)
GetAnimationBaseValue(DependencyProperty)

Returns the non-animated value of the specified DependencyProperty.

(Inherited from Animatable)
GetAsFrozen()

Creates a frozen copy of the Freezable, using base (non-animated) property values. Because the copy is frozen, any frozen sub-objects are copied by reference.

(Inherited from Freezable)
GetAsFrozenCore(Freezable)

Makes the instance a frozen clone of the specified Freezable using base (non-animated) property values.

(Inherited from Freezable)
GetCurrentValueAsFrozen()

Creates a frozen copy of the Freezable using current property values. Because the copy is frozen, any frozen sub-objects are copied by reference.

(Inherited from Freezable)
GetCurrentValueAsFrozenCore(Freezable)

Makes the current instance a frozen clone of the specified Freezable. If the object has animated dependency properties, their current animated values are copied.

(Inherited from Freezable)
GetHashCode()

Gets a hash code for this DependencyObject.

(Inherited from DependencyObject)
GetLocalValueEnumerator()

Creates a specialized enumerator for determining which dependency properties have locally set values on this DependencyObject.

(Inherited from DependencyObject)
GetType()

Gets the Type of the current instance.

(Inherited from Object)
GetValue(DependencyProperty)

Returns the current effective value of a dependency property on this instance of a DependencyObject.

(Inherited from DependencyObject)
InvalidateProperty(DependencyProperty)

Re-evaluates the effective value for the specified dependency property.

(Inherited from DependencyObject)
MemberwiseClone()

Creates a shallow copy of the current Object.

(Inherited from Object)
OnChanged()

Called when the current Freezable object is modified.

(Inherited from Freezable)
OnFreezablePropertyChanged(DependencyObject, DependencyObject, DependencyProperty)

This member supports the Windows Presentation Foundation (WPF) infrastructure and is not intended to be used directly from your code.

(Inherited from Freezable)
OnFreezablePropertyChanged(DependencyObject, DependencyObject)

Ensures that appropriate context pointers are established for a DependencyObjectType data member that has just been set.

(Inherited from Freezable)
OnPropertyChanged(DependencyPropertyChangedEventArgs)

Overrides the DependencyObject implementation of OnPropertyChanged(DependencyPropertyChangedEventArgs) to also invoke any Changed handlers in response to a changing dependency property of type Freezable.

(Inherited from Freezable)
ReadLocalValue(DependencyProperty)

Returns the local value of a dependency property, if it exists.

(Inherited from DependencyObject)
ReadPreamble()

Ensures that the Freezable is being accessed from a valid thread. Inheritors of Freezable must call this method at the beginning of any API that reads data members that are not dependency properties.

(Inherited from Freezable)
SetCurrentValue(DependencyProperty, Object)

Sets the value of a dependency property without changing its value source.

(Inherited from DependencyObject)
SetValue(DependencyProperty, Object)

Sets the local value of a dependency property, specified by its dependency property identifier.

(Inherited from DependencyObject)
SetValue(DependencyPropertyKey, Object)

Sets the local value of a read-only dependency property, specified by the DependencyPropertyKey identifier of the dependency property.

(Inherited from DependencyObject)
ShouldSerializeProperty(DependencyProperty)

Returns a value that indicates whether serialization processes should serialize the value for the provided dependency property.

(Inherited from DependencyObject)
ToString()

Return string representation of this Brush.

(Inherited from Brush)
ToString(IFormatProvider)

Creates a string representation of this object based on the specified culture-specific formatting information.

(Inherited from Brush)
VerifyAccess()

Enforces that the calling thread has access to this DispatcherObject.

(Inherited from DispatcherObject)
WritePostscript()

Raises the Changed event for the Freezable and invokes its OnChanged() method. Classes that derive from Freezable should call this method at the end of any API that modifies class members that are not stored as dependency properties.

(Inherited from Freezable)
WritePreamble()

Verifies that the Freezable is not frozen and that it is being accessed from a valid threading context. Freezable inheritors should call this method at the beginning of any API that writes to data members that are not dependency properties.

(Inherited from Freezable)

Events

Changed

Occurs when the Freezable or an object it contains is modified.

(Inherited from Freezable)

Explicit Interface Implementations

IFormattable.ToString(String, IFormatProvider)

Formats the value of the current instance using the specified format.

(Inherited from Brush)

Applies to

See also