gecko-dev/dom/animation/Animation.h

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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 http://mozilla.org/MPL/2.0/. */
#ifndef mozilla_dom_Animation_h
#define mozilla_dom_Animation_h
#include "nsWrapperCache.h"
#include "nsCycleCollectionParticipant.h"
#include "mozilla/Attributes.h"
#include "mozilla/EffectCompositor.h" // For EffectCompositor::CascadeLevel
#include "mozilla/LinkedList.h"
#include "mozilla/TimeStamp.h" // for TimeStamp, TimeDuration
#include "mozilla/dom/AnimationBinding.h" // for AnimationPlayState
#include "mozilla/dom/AnimationTimeline.h" // for AnimationTimeline
#include "mozilla/DOMEventTargetHelper.h" // for DOMEventTargetHelper
#include "mozilla/dom/KeyframeEffect.h" // for KeyframeEffectReadOnly
#include "mozilla/dom/Promise.h" // for Promise
#include "nsCSSProperty.h" // for nsCSSProperty
#include "nsIGlobalObject.h"
// X11 has a #define for CurrentTime.
#ifdef CurrentTime
#undef CurrentTime
#endif
// GetCurrentTime is defined in winbase.h as zero argument macro forwarding to
// GetTickCount().
#ifdef GetCurrentTime
#undef GetCurrentTime
#endif
struct JSContext;
class nsCSSPropertySet;
class nsIDocument;
class nsPresContext;
namespace mozilla {
class AnimValuesStyleRule;
namespace dom {
class CSSAnimation;
class CSSTransition;
class Animation
: public DOMEventTargetHelper
, public LinkedListElement<Animation>
{
protected:
virtual ~Animation() {}
public:
explicit Animation(nsIGlobalObject* aGlobal)
: DOMEventTargetHelper(aGlobal)
, mPlaybackRate(1.0)
, mPendingState(PendingState::NotPending)
, mAnimationIndex(sNextAnimationIndex++)
, mFinishedAtLastComposeStyle(false)
, mIsRelevant(false)
, mFinishedIsResolved(false)
{
}
NS_DECL_ISUPPORTS_INHERITED
NS_DECL_CYCLE_COLLECTION_CLASS_INHERITED(Animation,
DOMEventTargetHelper)
AnimationTimeline* GetParentObject() const { return mTimeline; }
virtual JSObject* WrapObject(JSContext* aCx,
JS::Handle<JSObject*> aGivenProto) override;
virtual CSSAnimation* AsCSSAnimation() { return nullptr; }
virtual const CSSAnimation* AsCSSAnimation() const { return nullptr; }
virtual CSSTransition* AsCSSTransition() { return nullptr; }
virtual const CSSTransition* AsCSSTransition() const { return nullptr; }
/**
* Flag to pass to Play to indicate whether or not it should automatically
* rewind the current time to the start point if the animation is finished.
* For regular calls to play() from script we should do this, but when a CSS
* animation's animation-play-state changes we shouldn't rewind the animation.
*/
enum class LimitBehavior {
AutoRewind,
Continue
};
// Animation interface methods
static already_AddRefed<Animation>
Constructor(const GlobalObject& aGlobal,
KeyframeEffectReadOnly* aEffect,
AnimationTimeline* aTimeline,
ErrorResult& aRv);
void GetId(nsAString& aResult) const { aResult = mId; }
void SetId(const nsAString& aId);
KeyframeEffectReadOnly* GetEffect() const { return mEffect; }
void SetEffect(KeyframeEffectReadOnly* aEffect);
AnimationTimeline* GetTimeline() const { return mTimeline; }
void SetTimeline(AnimationTimeline* aTimeline);
Nullable<TimeDuration> GetStartTime() const { return mStartTime; }
void SetStartTime(const Nullable<TimeDuration>& aNewStartTime);
Nullable<TimeDuration> GetCurrentTime() const;
void SetCurrentTime(const TimeDuration& aNewCurrentTime);
double PlaybackRate() const { return mPlaybackRate; }
void SetPlaybackRate(double aPlaybackRate);
AnimationPlayState PlayState() const;
virtual Promise* GetReady(ErrorResult& aRv);
virtual Promise* GetFinished(ErrorResult& aRv);
void Cancel();
virtual void Finish(ErrorResult& aRv);
virtual void Play(ErrorResult& aRv, LimitBehavior aLimitBehavior);
virtual void Pause(ErrorResult& aRv);
virtual void Reverse(ErrorResult& aRv);
bool IsRunningOnCompositor() const;
IMPL_EVENT_HANDLER(finish);
IMPL_EVENT_HANDLER(cancel);
// Wrapper functions for Animation DOM methods when called
// from script.
//
// We often use the same methods internally and from script but when called
// from script we (or one of our subclasses) perform extra steps such as
// flushing style or converting the return type.
Nullable<double> GetStartTimeAsDouble() const;
void SetStartTimeAsDouble(const Nullable<double>& aStartTime);
Nullable<double> GetCurrentTimeAsDouble() const;
void SetCurrentTimeAsDouble(const Nullable<double>& aCurrentTime,
ErrorResult& aRv);
virtual AnimationPlayState PlayStateFromJS() const { return PlayState(); }
virtual void PlayFromJS(ErrorResult& aRv)
{
Play(aRv, LimitBehavior::AutoRewind);
}
/**
* PauseFromJS is currently only here for symmetry with PlayFromJS but
* in future we will likely have to flush style in
* CSSAnimation::PauseFromJS so we leave it for now.
*/
void PauseFromJS(ErrorResult& aRv) { Pause(aRv); }
// Wrapper functions for Animation DOM methods when called from style.
virtual void CancelFromStyle() { DoCancel(); }
virtual void Tick();
bool NeedsTicks() const
{
AnimationPlayState playState = PlayState();
return playState == AnimationPlayState::Running ||
playState == AnimationPlayState::Pending;
}
/**
* Set the time to use for starting or pausing a pending animation.
*
* Typically, when an animation is played, it does not start immediately but
* is added to a table of pending animations on the document of its effect.
* In the meantime it sets its hold time to the time from which playback
* should begin.
*
* When the document finishes painting, any pending animations in its table
* are marked as being ready to start by calling StartOnNextTick.
* The moment when the paint completed is also recorded, converted to a
* timeline time, and passed to StartOnTick. This is so that when these
* animations do start, they can be timed from the point when painting
* completed.
*
* After calling TriggerOnNextTick, animations remain in the pending state
* until the next refresh driver tick. At that time they transition out of
* the pending state using the time passed to TriggerOnNextTick as the
* effective time at which they resumed.
*
* This approach means that any setup time required for performing the
* initial paint of an animation such as layerization is not deducted from
* the running time of the animation. Without this we can easily drop the
* first few frames of an animation, or, on slower devices, the whole
* animation.
*
* Furthermore:
*
* - Starting the animation immediately when painting finishes is problematic
* because the start time of the animation will be ahead of its timeline
* (since the timeline time is based on the refresh driver time).
* That's a problem because the animation is playing but its timing
* suggests it starts in the future. We could update the timeline to match
* the start time of the animation but then we'd also have to update the
* timing and style of all animations connected to that timeline or else be
* stuck in an inconsistent state until the next refresh driver tick.
*
* - If we simply use the refresh driver time on its next tick, the lag
* between triggering an animation and its effective start is unacceptably
* long.
*
* For pausing, we apply the same asynchronous approach. This is so that we
* synchronize with animations that are running on the compositor. Otherwise
* if the main thread lags behind the compositor there will be a noticeable
* jump backwards when the main thread takes over. Even though main thread
* animations could be paused immediately, we do it asynchronously for
* consistency and so that animations paused together end up in step.
*
* Note that the caller of this method is responsible for removing the
* animation from any PendingAnimationTracker it may have been added to.
*/
void TriggerOnNextTick(const Nullable<TimeDuration>& aReadyTime);
/**
* Testing only: Start or pause a pending animation using the current
* timeline time. This is used to support existing tests that expect
* animations to begin immediately. Ideally we would rewrite the those tests
* and get rid of this method, but there are a lot of them.
*
* As with TriggerOnNextTick, the caller of this method is responsible for
* removing the animation from any PendingAnimationTracker it may have been
* added to.
*/
void TriggerNow();
/**
* When StartOnNextTick is called, we store the ready time but we don't apply
* it until the next tick. In the meantime, GetStartTime() will return null.
*
* However, if we build layer animations again before the next tick, we
* should initialize them with the start time that GetStartTime() will return
* on the next tick.
*
* If we were to simply set the start time of layer animations to null, their
* start time would be updated to the current wallclock time when rendering
* finishes, thus making them out of sync with the start time stored here.
* This, in turn, will make the animation jump backwards when we build
* animations on the next tick and apply the start time stored here.
*
* This method returns the start time, if resolved. Otherwise, if we have
* a pending ready time, it returns the corresponding start time. If neither
* of those are available, it returns null.
*/
Nullable<TimeDuration> GetCurrentOrPendingStartTime() const;
/**
* Converts a time in the timescale of this Animation's currentTime, to a
* TimeStamp. Returns a null TimeStamp if the conversion cannot be performed
* because of the current state of this Animation (e.g. it has no timeline, a
* zero playbackRate, an unresolved start time etc.) or the value of the time
* passed-in (e.g. an infinite time).
*/
TimeStamp AnimationTimeToTimeStamp(const StickyTimeDuration& aTime) const;
bool IsPausedOrPausing() const
{
return PlayState() == AnimationPlayState::Paused ||
mPendingState == PendingState::PausePending;
}
bool HasInPlayEffect() const
{
return GetEffect() && GetEffect()->IsInPlay();
}
bool HasCurrentEffect() const
{
return GetEffect() && GetEffect()->IsCurrent();
}
bool IsInEffect() const
{
return GetEffect() && GetEffect()->IsInEffect();
}
/**
* "Playing" is different to "running". An animation in its delay phase is
* still running but we only consider it playing when it is in its active
* interval. This definition is used for fetching the animations that are
* candidates for running on the compositor (since we don't ship animations
* to the compositor when they are in their delay phase or paused including
* being effectively paused due to having a zero playback rate).
*/
bool IsPlaying() const
{
// We need to have an effect in its active interval, and
// be either running or waiting to run with a non-zero playback rate.
return HasInPlayEffect() &&
mPlaybackRate != 0.0 &&
(PlayState() == AnimationPlayState::Running ||
mPendingState == PendingState::PlayPending);
}
bool IsRelevant() const { return mIsRelevant; }
void UpdateRelevance();
/**
* Returns true if this Animation has a lower composite order than aOther.
*/
bool HasLowerCompositeOrderThan(const Animation& aOther) const;
/**
* Returns the level at which the effect(s) associated with this Animation
* are applied to the CSS cascade.
*/
virtual EffectCompositor::CascadeLevel CascadeLevel() const
{
return EffectCompositor::CascadeLevel::Animations;
}
/**
* Returns true if this animation does not currently need to update
* style on the main thread (e.g. because it is empty, or is
* running on the compositor).
*/
bool CanThrottle() const;
/**
* Updates |aStyleRule| with the animation values of this animation's effect,
* if any.
* Any properties already contained in |aSetProperties| are not changed. Any
* properties that are changed are added to |aSetProperties|.
*/
void ComposeStyle(RefPtr<AnimValuesStyleRule>& aStyleRule,
nsCSSPropertySet& aSetProperties);
void NotifyEffectTimingUpdated();
protected:
void SilentlySetCurrentTime(const TimeDuration& aNewCurrentTime);
void SilentlySetPlaybackRate(double aPlaybackRate);
void DoCancel();
void DoPlay(ErrorResult& aRv, LimitBehavior aLimitBehavior);
void DoPause(ErrorResult& aRv);
void ResumeAt(const TimeDuration& aReadyTime);
void PauseAt(const TimeDuration& aReadyTime);
void FinishPendingAt(const TimeDuration& aReadyTime)
{
if (mPendingState == PendingState::PlayPending) {
ResumeAt(aReadyTime);
} else if (mPendingState == PendingState::PausePending) {
PauseAt(aReadyTime);
} else {
NS_NOTREACHED("Can't finish pending if we're not in a pending state");
}
}
/**
* Finishing behavior depends on if changes to timing occurred due
* to a seek or regular playback.
*/
enum class SeekFlag {
NoSeek,
DidSeek
};
enum class SyncNotifyFlag {
Sync,
Async
};
virtual void UpdateTiming(SeekFlag aSeekFlag,
SyncNotifyFlag aSyncNotifyFlag);
void UpdateFinishedState(SeekFlag aSeekFlag,
SyncNotifyFlag aSyncNotifyFlag);
void UpdateEffect();
void FlushStyle() const;
void PostUpdate();
void ResetFinishedPromise();
void MaybeResolveFinishedPromise();
void DoFinishNotification(SyncNotifyFlag aSyncNotifyFlag);
void DoFinishNotificationImmediately();
void DispatchPlaybackEvent(const nsAString& aName);
/**
* Remove this animation from the pending animation tracker and reset
* mPendingState as necessary. The caller is responsible for resolving or
* aborting the mReady promise as necessary.
*/
void CancelPendingTasks();
bool IsPossiblyOrphanedPendingAnimation() const;
StickyTimeDuration EffectEnd() const;
nsIDocument* GetRenderedDocument() const;
nsPresContext* GetPresContext() const;
RefPtr<AnimationTimeline> mTimeline;
RefPtr<KeyframeEffectReadOnly> mEffect;
// The beginning of the delay period.
Nullable<TimeDuration> mStartTime; // Timeline timescale
Nullable<TimeDuration> mHoldTime; // Animation timescale
Nullable<TimeDuration> mPendingReadyTime; // Timeline timescale
Nullable<TimeDuration> mPreviousCurrentTime; // Animation timescale
double mPlaybackRate;
// A Promise that is replaced on each call to Play()
// and fulfilled when Play() is successfully completed.
// This object is lazily created by GetReady.
// See http://w3c.github.io/web-animations/#current-ready-promise
RefPtr<Promise> mReady;
// A Promise that is resolved when we reach the end of the effect, or
// 0 when playing backwards. The Promise is replaced if the animation is
// finished but then a state change makes it not finished.
// This object is lazily created by GetFinished.
// See http://w3c.github.io/web-animations/#current-finished-promise
RefPtr<Promise> mFinished;
// Indicates if the animation is in the pending state (and what state it is
// waiting to enter when it finished pending). We use this rather than
// checking if this animation is tracked by a PendingAnimationTracker because
// the animation will continue to be pending even after it has been removed
// from the PendingAnimationTracker while it is waiting for the next tick
// (see TriggerOnNextTick for details).
enum class PendingState { NotPending, PlayPending, PausePending };
PendingState mPendingState;
static uint64_t sNextAnimationIndex;
// The relative position of this animation within the global animation list.
// This is kNoIndex while the animation is in the idle state and is updated
// each time the animation transitions out of the idle state.
//
// Note that subclasses such as CSSTransition and CSSAnimation may repurpose
// this member to implement their own brand of sorting. As a result, it is
// possible for two different objects to have the same index.
uint64_t mAnimationIndex;
bool mFinishedAtLastComposeStyle;
// Indicates that the animation should be exposed in an element's
// getAnimations() list.
bool mIsRelevant;
nsRevocableEventPtr<nsRunnableMethod<Animation>> mFinishNotificationTask;
// True if mFinished is resolved or would be resolved if mFinished has
// yet to be created. This is not set when mFinished is rejected since
// in that case mFinished is immediately reset to represent a new current
// finished promise.
bool mFinishedIsResolved;
nsString mId;
};
} // namespace dom
} // namespace mozilla
#endif // mozilla_dom_Animation_h