T CacheAndInitializeKeyframeAnimation <T>(KeyFrameAnimation_ source, T target)
where T : KeyFrameAnimation_
{
CacheAndInitializeAnimation(source, target);
target.Duration = source.Duration;
return(target);
}
public static void WithKeyFrame(
TranslationContext context,
CompositionObject compObject,
string target,
KeyFrameAnimation_ animation,
double scale = 1,
double offset = 0)
{
Debug.Assert(offset >= 0, "Precondition");
Debug.Assert(scale <= 1, "Precondition");
Debug.Assert(animation.KeyFrameCount > 0, "Precondition");
var state = context.GetStateCache <StateCache>();
// Start the animation ...
compObject.StartAnimation(target, animation);
// ... but pause it immediately so that it doesn't react to time. Instead, bind
// its progress to the progress of the composition.
var controller = compObject.TryGetAnimationController(target);
controller !.Pause();
// Bind it to the root visual's Progress property, scaling and offsetting if necessary.
var key = new ScaleAndOffset(scale, offset);
if (!state.ProgressBindingAnimations.TryGetValue(key, out var bindingAnimation))
{
bindingAnimation = context.ObjectFactory.CreateExpressionAnimation(ExpressionFactory.ScaledAndOffsetRootProgress(scale, offset));
bindingAnimation.SetReferenceParameter(ExpressionFactory.RootName, context.RootVisual !);
if (context.AddDescriptions)
{
// Give the animation a nice readable name in codegen.
var name = key.Offset != 0 || key.Scale != 1
? "RootProgressRemapped"
: "RootProgress";
bindingAnimation.SetName(name);
}
state.ProgressBindingAnimations.Add(key, bindingAnimation);
}
// Bind the controller's Progress with a single Progress property on the scene root.
// The Progress property provides the time reference for the animation.
controller.StartAnimation("Progress", bindingAnimation);
}
