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/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=8 sts=2 et sw=2 tw=80: */
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this file,
* You can obtain one at */
#ifndef mozilla_dom_AnimationTimeline_h
#define mozilla_dom_AnimationTimeline_h
#include "nsISupports.h"
#include "nsWrapperCache.h"
#include "nsCycleCollectionParticipant.h"
#include "mozilla/AnimationUtils.h"
#include "nsHashKeys.h"
#include "nsIGlobalObject.h"
#include "nsTHashSet.h"
namespace mozilla::dom {
class Animation;
class Document;
class ScrollTimeline;
class AnimationTimeline : public nsISupports, public nsWrapperCache {
AnimationTimeline(nsIGlobalObject* aWindow, RTPCallerType);
struct TickState {
TickState() = default;
// Nothing here, but this might be useful in the future.
virtual ~AnimationTimeline();
// Tick animations and may remove them from the list if we don't need to tick
// it. Return true if any animations need to be ticked.
bool Tick(TickState&);
nsIGlobalObject* GetParentObject() const { return mWindow; }
// AnimationTimeline methods
virtual Nullable<TimeDuration> GetCurrentTimeAsDuration() const = 0;
// Wrapper functions for AnimationTimeline DOM methods when called from
// script.
Nullable<double> GetCurrentTimeAsDouble() const {
return AnimationUtils::TimeDurationToDouble(GetCurrentTimeAsDuration(),
TimeStamp GetCurrentTimeAsTimeStamp() const {
Nullable<TimeDuration> currentTime = GetCurrentTimeAsDuration();
return !currentTime.IsNull() ? ToTimeStamp(currentTime.Value())
: TimeStamp();
* Returns true if the times returned by GetCurrentTimeAsDuration() are
* convertible to and from wallclock-based TimeStamp (e.g. from
* TimeStamp::Now()) values using ToTimelineTime() and ToTimeStamp().
* Typically this is true, but it will be false in the case when this
* timeline has no refresh driver or is tied to a refresh driver under test
* control.
virtual bool TracksWallclockTime() const = 0;
* Converts a TimeStamp to the equivalent value in timeline time.
* Note that when TracksWallclockTime() is false, there is no correspondence
* between timeline time and wallclock time. In such a case, passing a
* timestamp from TimeStamp::Now() to this method will not return a
* meaningful result.
virtual Nullable<TimeDuration> ToTimelineTime(
const TimeStamp& aTimeStamp) const = 0;
virtual TimeStamp ToTimeStamp(const TimeDuration& aTimelineTime) const = 0;
* Inform this timeline that |aAnimation| which is or was observing the
* timeline, has been updated. This serves as both the means to associate
* AND disassociate animations with a timeline. The timeline itself will
* determine if it needs to begin, continue or stop tracking this animation.
virtual void NotifyAnimationUpdated(Animation& aAnimation);
* Returns true if any CSS animations, CSS transitions or Web animations are
* currently associated with this timeline. As soon as an animation is
* applied to an element it is associated with the timeline even if it has a
* delayed start, so this includes animations that may not be active for some
* time.
bool HasAnimations() const { return !mAnimations.IsEmpty(); }
virtual void RemoveAnimation(Animation* aAnimation);
virtual void NotifyAnimationContentVisibilityChanged(Animation* aAnimation,
bool aIsVisible);
void UpdateHiddenByContentVisibility();
virtual Document* GetDocument() const = 0;
virtual bool IsMonotonicallyIncreasing() const = 0;
RTPCallerType GetRTPCallerType() const { return mRTPCallerType; }
virtual bool IsScrollTimeline() const { return false; }
virtual const ScrollTimeline* AsScrollTimeline() const { return nullptr; }
virtual bool IsViewTimeline() const { return false; }
// For a monotonic timeline, there is no upper bound on current time, and
// timeline duration is unresolved. For a non-monotonic (e.g. scroll)
// timeline, the duration has a fixed upper bound.
virtual Nullable<TimeDuration> TimelineDuration() const { return nullptr; }
nsCOMPtr<nsIGlobalObject> mWindow;
// Animations observing this timeline
// We store them in (a) a hashset for quick lookup, and (b) a LinkedList to
// maintain a fixed sampling order. Animations that are hidden by
// `content-visibility` are not sampled and will only be in the hashset.
// The LinkedList should always be a subset of the hashset.
// The hashset keeps a strong reference to each animation since
// dealing with addref/release with LinkedList is difficult.
using AnimationSet = nsTHashSet<nsRefPtrHashKey<dom::Animation>>;
AnimationSet mAnimations;
LinkedList<dom::Animation> mAnimationOrder;
// Whether the Timeline is System, ResistFingerprinting, or neither
enum RTPCallerType mRTPCallerType;
} // namespace mozilla::dom
#endif // mozilla_dom_AnimationTimeline_h