Gets or sets the time at which the key frame's target Value should be reached.
Assembly: PresentationCore (in PresentationCore.dll)
XMLNS for XAML: http://schemas.microsoft.com/winfx/2006/xaml/presentation, http://schemas.microsoft.com/netfx/2007/xaml/presentation
Property ValueType: System.Windows.Media.Animation.KeyTime
The time at which the key frame's current value should be equal to its Value property. The default value is Uniform.
In the following example, Point3DAnimationUsingKeyFrames is used to animate the position of a PerspectiveCamera in a 3D scene. In addition, Vector3DAnimationUsingKeyFrames is used to animate the direction the camera is pointing in the 3D scene. Both of these animations use several key frames which create a series of animation effects:
SplinePoint3DKeyFrame and SplineVector3DKeyFrame are used to create a variable transition between values depending on the KeySpline property. In the example below, the animation starts off slow but toward the end of the time segment, speeds up exponentially.
<Page xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" > <DockPanel> <Viewbox> <Canvas Width="321" Height="201"> <Viewport3D Name="MyAnimatedObject" ClipToBounds="True" Width="150" Height="150" Canvas.Left="0" Canvas.Top="10"> <!-- Defines the camera used to view the 3D object. The position and direction of this camera is animated in the Storyboard below. --> <Viewport3D.Camera> <PerspectiveCamera x:Name="myPerspectiveCamera" Position="0,0,2" LookDirection="0,0,-1" FieldOfView="45" /> </Viewport3D.Camera> <Viewport3D.Children> <ModelVisual3D> <ModelVisual3D.Children> <!-- This resource defines the 3D cube that is used in this example.--> <StaticResource ResourceKey="PictureCubeModelVisual3DResource" /> </ModelVisual3D.Children> </ModelVisual3D> </Viewport3D.Children> <Viewport3D.Triggers> <EventTrigger RoutedEvent="Viewport3D.Loaded"> <BeginStoryboard> <Storyboard> <!-- This animation moves the camera around the object. The object is not changing position or rotating but moving the camera makes it appear that it is.--> <Point3DAnimationUsingKeyFrames Storyboard.TargetName="myPerspectiveCamera" Storyboard.TargetProperty="Position" > <Point3DAnimationUsingKeyFrames.KeyFrames> <!-- Using a LinearPoint3DKeyFrame, the camera moves steadily from its starting position to a new position that is to the upper right and a little farther away. This happens over the first second of the animation. --> <LinearPoint3DKeyFrame Value="1,2,3" KeyTime="0:0:1" /> <!-- Using a DiscretePoint3DKeyFrame, the camera suddenly moves farther away from the object. This happens immdeiately after the first 1 and a half second of the animation. --> <DiscretePoint3DKeyFrame Value="1,2,5" KeyTime="0:0:1.5" /> <!-- Using a SplinePoint3DKeyFrame, the camera moves back to its starting point. The animation starts out slowly at first and then speeds up. This KeyFrame ends after the fourth second. --> <SplinePoint3DKeyFrame KeySpline="0.6,0.0 0.9,0.00" Value="0,0,2" KeyTime="0:0:4" /> </Point3DAnimationUsingKeyFrames.KeyFrames> </Point3DAnimationUsingKeyFrames> <!-- As the position of the camera changes using the Point3DAnimation above, the direction the camera is pointing swivels to keep the object within the view of the camera. --> <Vector3DAnimationUsingKeyFrames Storyboard.TargetName="myPerspectiveCamera" Storyboard.TargetProperty="LookDirection" > <Vector3DAnimationUsingKeyFrames.KeyFrames> <!-- Using a LinearVector3DKeyFrame, the camera swivels steadily from its starting position down and to the left. This happens over the first second of the animation. --> <LinearVector3DKeyFrame Value="-1,-2,-3" KeyTime="0:0:1" /> <!-- Using a DiscreteVector3DKeyFrame, the camera suddenly swivels up. This happens immdeiately after the first 1 and a half second of the animation. --> <DiscreteVector3DKeyFrame Value="-1,-1,-3" KeyTime="0:0:1.5" /> <!-- Using a SplineVector3DKeyFrame, the camera swivels back to its starting point. The animation starts out slowly at first and then speeds up. This KeyFrame ends after the fourth second. --> <SplineVector3DKeyFrame KeySpline="0.6,0.0 0.9,0.00" Value="0,0,-1" KeyTime="0:0:4" /> </Vector3DAnimationUsingKeyFrames.KeyFrames> </Vector3DAnimationUsingKeyFrames> </Storyboard> </BeginStoryboard> </EventTrigger> </Viewport3D.Triggers> </Viewport3D> </Canvas> </Viewbox> </DockPanel> </Page>
|How to: Control Key-Frame Animation Timing||This example shows how to control the timing of key frames within a key-frame animation. Like other animations, key-frame animations have a Duration property. In addition to specifying the duration of an animation, you need to specify what part of that duration is allotted to each of its key frames. To allot the time, you specify a KeyTime for each key frame in the animation.|