C++ KeyframeEffectReadOnly类代码示例

void
Animation::PostUpdate()
{
  if (!mEffect) {
    return;
  }

  KeyframeEffectReadOnly* keyframeEffect = mEffect->AsKeyframeEffect();
  if (!keyframeEffect) {
    return;
  }

  Maybe<NonOwningAnimationTarget> target = keyframeEffect->GetTarget();
  if (!target) {
    return;
  }

  nsPresContext* presContext = keyframeEffect->GetPresContext();
  if (!presContext) {
    return;
  }

  presContext->EffectCompositor()
             ->RequestRestyle(target->mElement,
                              target->mPseudoType,
                              EffectCompositor::RestyleType::Layer,
                              CascadeLevel());
}

// A helper function for IsScaleSubjectToAnimation which returns true if the
// given AnimationCollection contains a current effect that animates scale.
static bool
ContainsAnimatedScale(AnimationCollection* aCollection, nsIFrame* aFrame)
{
  if (!aCollection) {
    return false;
  }

  for (dom::Animation* anim : aCollection->mAnimations) {
    if (!anim->HasCurrentEffect()) {
      continue;
    }
    KeyframeEffectReadOnly* effect = anim->GetEffect();
    for (const AnimationProperty& prop : effect->Properties()) {
      if (prop.mProperty != eCSSProperty_transform) {
        continue;
      }
      for (AnimationPropertySegment segment : prop.mSegments) {
        gfxSize from = segment.mFromValue.GetScaleValue(aFrame);
        if (from != gfxSize(1.0f, 1.0f)) {
          return true;
        }
        gfxSize to = segment.mToValue.GetScaleValue(aFrame);
        if (to != gfxSize(1.0f, 1.0f)) {
          return true;
        }
      }
    }
  }

  return false;
}

void
Animation::UpdateEffect()
{
  if (mEffect) {
    UpdateRelevance();

    KeyframeEffectReadOnly* keyframeEffect = mEffect->AsKeyframeEffect();
    if (keyframeEffect) {
      keyframeEffect->NotifyAnimationTimingUpdated();
    }
  }
}

static void
UpdateOldAnimationPropertiesWithNew(
    CSSAnimation& aOld,
    TimingParams& aNewTiming,
    nsTArray<Keyframe>& aNewKeyframes,
    bool aNewIsStylePaused,
    nsStyleContext* aStyleContext)
{
  bool animationChanged = false;

  // Update the old from the new so we can keep the original object
  // identity (and any expando properties attached to it).
  if (aOld.GetEffect()) {
    AnimationEffectReadOnly* oldEffect = aOld.GetEffect();
    animationChanged = oldEffect->SpecifiedTiming() != aNewTiming;
    oldEffect->SetSpecifiedTiming(aNewTiming);

    KeyframeEffectReadOnly* oldKeyframeEffect = oldEffect->AsKeyframeEffect();
    if (oldKeyframeEffect) {
      oldKeyframeEffect->SetKeyframes(Move(aNewKeyframes), aStyleContext);
    }
  }

  // Handle changes in play state. If the animation is idle, however,
  // changes to animation-play-state should *not* restart it.
  if (aOld.PlayState() != AnimationPlayState::Idle) {
    // CSSAnimation takes care of override behavior so that,
    // for example, if the author has called pause(), that will
    // override the animation-play-state.
    // (We should check aNew->IsStylePaused() but that requires
    //  downcasting to CSSAnimation and we happen to know that
    //  aNew will only ever be paused by calling PauseFromStyle
    //  making IsPausedOrPausing synonymous in this case.)
    if (!aOld.IsStylePaused() && aNewIsStylePaused) {
      aOld.PauseFromStyle();
      animationChanged = true;
    } else if (aOld.IsStylePaused() && !aNewIsStylePaused) {
      aOld.PlayFromStyle();
      animationChanged = true;
    }
  }

  // Updating the effect timing above might already have caused the
  // animation to become irrelevant so only add a changed record if
  // the animation is still relevant.
  if (animationChanged && aOld.IsRelevant()) {
    nsNodeUtils::AnimationChanged(&aOld);
  }
}

/* static */ already_AddRefed<KeyframeEffectType>
KeyframeEffectReadOnly::ConstructKeyframeEffect(const GlobalObject& aGlobal,
                                                KeyframeEffectReadOnly& aSource,
                                                ErrorResult& aRv)
{
  nsIDocument* doc = AnimationUtils::GetCurrentRealmDocument(aGlobal.Context());
  if (!doc) {
    aRv.Throw(NS_ERROR_FAILURE);
    return nullptr;
  }

  // Create a new KeyframeEffectReadOnly object with aSource's target,
  // iteration composite operation, composite operation, and spacing mode.
  // The constructor creates a new AnimationEffect(ReadOnly) object by
  // aSource's TimingParams.
  // Note: we don't need to re-throw exceptions since the value specified on
  //       aSource's timing object can be assumed valid.
  RefPtr<KeyframeEffectType> effect =
    new KeyframeEffectType(doc,
                           aSource.mTarget,
                           aSource.SpecifiedTiming(),
                           aSource.mEffectOptions);
  // Copy cumulative change hint. mCumulativeChangeHint should be the same as
  // the source one because both of targets are the same.
  effect->mCumulativeChangeHint = aSource.mCumulativeChangeHint;

  // Copy aSource's keyframes and animation properties.
  // Note: We don't call SetKeyframes directly, which might revise the
  //       computed offsets and rebuild the animation properties.
  // FIXME: Bug 1314537: We have to make sure SharedKeyframeList is handled
  //        properly.
  effect->mKeyframes = aSource.mKeyframes;
  effect->mProperties = aSource.mProperties;
  return effect.forget();
}

void
nsAnimationManager::CopyIsRunningOnCompositor(
  KeyframeEffectReadOnly& aSourceEffect,
  KeyframeEffectReadOnly& aDestEffect)
{
  nsCSSPropertySet sourceProperties;

  for (AnimationProperty& property : aSourceEffect.Properties()) {
    if (property.mIsRunningOnCompositor) {
      sourceProperties.AddProperty(property.mProperty);
    }
  }

  for (AnimationProperty& property : aDestEffect.Properties()) {
    if (sourceProperties.HasProperty(property.mProperty)) {
      property.mIsRunningOnCompositor = true;
    }
  }
}

bool AnimationStack::getAnimatedBoundingBox(FloatBox& box,
                                            CSSPropertyID property) const {
  FloatBox originalBox(box);
  for (const auto& sampledEffect : m_sampledEffects) {
    if (sampledEffect->effect() &&
        sampledEffect->effect()->affects(PropertyHandle(property))) {
      KeyframeEffectReadOnly* effect = sampledEffect->effect();
      const Timing& timing = effect->specifiedTiming();
      double startRange = 0;
      double endRange = 1;
      timing.timingFunction->range(&startRange, &endRange);
      FloatBox expandingBox(originalBox);
      if (!CompositorAnimations::getAnimatedBoundingBox(
              expandingBox, *effect->model(), startRange, endRange))
        return false;
      box.expandTo(expandingBox);
    }
  }
  return true;
}

static inline Element*
GetTarget(Animation* aAnimation)
{
  KeyframeEffectReadOnly* effect = aAnimation->GetEffect();
  if (!effect) {
    return nullptr;
  }

  Element* target;
  nsCSSPseudoElements::Type pseudoType;
  effect->GetTarget(target, pseudoType);

  // If the animation targets a pseudo-element, we don't dispatch
  // notifications for it.  (In the future we will have PseudoElement
  // objects we can use as the target of the notifications.)
  if (pseudoType != nsCSSPseudoElements::ePseudo_NotPseudoElement) {
    return nullptr;
  }

  return effect->GetTarget();
}

void
Animation::Tick()
{
  // Finish pending if we have a pending ready time, but only if we also
  // have an active timeline.
  if (mPendingState != PendingState::NotPending &&
      !mPendingReadyTime.IsNull() &&
      mTimeline &&
      !mTimeline->GetCurrentTime().IsNull()) {
    // Even though mPendingReadyTime is initialized using TimeStamp::Now()
    // during the *previous* tick of the refresh driver, it can still be
    // ahead of the *current* timeline time when we are using the
    // vsync timer so we need to clamp it to the timeline time.
    mPendingReadyTime.SetValue(std::min(mTimeline->GetCurrentTime().Value(),
                                        mPendingReadyTime.Value()));
    FinishPendingAt(mPendingReadyTime.Value());
    mPendingReadyTime.SetNull();
  }

  if (IsPossiblyOrphanedPendingAnimation()) {
    MOZ_ASSERT(mTimeline && !mTimeline->GetCurrentTime().IsNull(),
               "Orphaned pending animations should have an active timeline");
    FinishPendingAt(mTimeline->GetCurrentTime().Value());
  }

  UpdateTiming(SeekFlag::NoSeek, SyncNotifyFlag::Async);

  if (!mEffect) {
    return;
  }

  // Update layers if we are newly finished.
  KeyframeEffectReadOnly* keyframeEffect = mEffect->AsKeyframeEffect();
  if (keyframeEffect &&
      !keyframeEffect->Properties().IsEmpty() &&
      !mFinishedAtLastComposeStyle &&
      PlayState() == AnimationPlayState::Finished) {
    PostUpdate();
  }
}

/* static */ void
nsAnimationManager::UpdateCascadeResults(
                      nsStyleContext* aStyleContext,
                      AnimationCollection* aElementAnimations)
{
  /*
   * Figure out which properties we need to examine.
   */

  // size of 2 since we only currently have 2 properties we animate on
  // the compositor
  nsAutoTArray<nsCSSProperty, 2> propertiesToTrack;

  {
    nsCSSPropertySet propertiesToTrackAsSet;

    for (size_t animIdx = aElementAnimations->mAnimations.Length();
         animIdx-- != 0; ) {
      const Animation* anim = aElementAnimations->mAnimations[animIdx];
      const KeyframeEffectReadOnly* effect = anim->GetEffect();
      if (!effect) {
        continue;
      }

      for (size_t propIdx = 0, propEnd = effect->Properties().Length();
           propIdx != propEnd; ++propIdx) {
        const AnimationProperty& prop = effect->Properties()[propIdx];
        // We only bother setting mWinsInCascade for properties that we
        // can animate on the compositor.
        if (nsCSSProps::PropHasFlags(prop.mProperty,
                                     CSS_PROPERTY_CAN_ANIMATE_ON_COMPOSITOR)) {
          if (!propertiesToTrackAsSet.HasProperty(prop.mProperty)) {
            propertiesToTrack.AppendElement(prop.mProperty);
            propertiesToTrackAsSet.AddProperty(prop.mProperty);
          }
        }
      }
    }
  }

  /*
   * Determine whether those properties are set in things that
   * override animations.
   */

  nsCSSPropertySet propertiesOverridden;
  nsRuleNode::ComputePropertiesOverridingAnimation(propertiesToTrack,
                                                   aStyleContext,
                                                   propertiesOverridden);

  /*
   * Set mWinsInCascade based both on what is overridden at levels
   * higher than animations and based on one animation overriding
   * another.
   *
   * We iterate from the last animation to the first, just like we do
   * when calling ComposeStyle from AnimationCollection::EnsureStyleRuleFor.
   * Later animations override earlier ones, so we add properties to the set
   * of overridden properties as we encounter them, if the animation is
   * currently in effect.
   */

  bool changed = false;
  for (size_t animIdx = aElementAnimations->mAnimations.Length();
       animIdx-- != 0; ) {
    CSSAnimation* anim =
      aElementAnimations->mAnimations[animIdx]->AsCSSAnimation();
    KeyframeEffectReadOnly* effect = anim->GetEffect();

    anim->mInEffectForCascadeResults = anim->IsInEffect();

    if (!effect) {
      continue;
    }

    for (size_t propIdx = 0, propEnd = effect->Properties().Length();
         propIdx != propEnd; ++propIdx) {
      AnimationProperty& prop = effect->Properties()[propIdx];
      // We only bother setting mWinsInCascade for properties that we
      // can animate on the compositor.
      if (nsCSSProps::PropHasFlags(prop.mProperty,
                                   CSS_PROPERTY_CAN_ANIMATE_ON_COMPOSITOR)) {
        bool newWinsInCascade =
          !propertiesOverridden.HasProperty(prop.mProperty);
        if (newWinsInCascade != prop.mWinsInCascade) {
          changed = true;
        }
        prop.mWinsInCascade = newWinsInCascade;

        if (prop.mWinsInCascade && anim->mInEffectForCascadeResults) {
          // This animation is in effect right now, so it overrides
          // earlier animations.  (For animations that aren't in effect,
          // we set mWinsInCascade as though they were, but they don't
          // suppress animations lower in the cascade.)
          propertiesOverridden.AddProperty(prop.mProperty);
        }
      }
    }
  }

//.........这里部分代码省略.........

nsIStyleRule*
nsAnimationManager::CheckAnimationRule(nsStyleContext* aStyleContext,
                                       mozilla::dom::Element* aElement)
{
  if (!mPresContext->IsDynamic()) {
    // For print or print preview, ignore animations.
    return nullptr;
  }

  // Everything that causes our animation data to change triggers a
  // style change, which in turn triggers a non-animation restyle.
  // Likewise, when we initially construct frames, we're not in a
  // style change, but also not in an animation restyle.

  const nsStyleDisplay* disp = aStyleContext->StyleDisplay();
  AnimationCollection* collection =
    GetAnimations(aElement, aStyleContext->GetPseudoType(), false);
  if (!collection &&
      disp->mAnimationNameCount == 1 &&
      disp->mAnimations[0].GetName().IsEmpty()) {
    return nullptr;
  }

  nsAutoAnimationMutationBatch mb(aElement);

  // build the animations list
  dom::DocumentTimeline* timeline = aElement->OwnerDoc()->Timeline();
  AnimationPtrArray newAnimations;
  if (!aStyleContext->IsInDisplayNoneSubtree()) {
    BuildAnimations(aStyleContext, aElement, timeline, newAnimations);
  }

  if (newAnimations.IsEmpty()) {
    if (collection) {
      // There might be transitions that run now that animations don't
      // override them.
      mPresContext->TransitionManager()->
        UpdateCascadeResultsWithAnimationsToBeDestroyed(collection);

      collection->Destroy();
    }
    return nullptr;
  }

  if (collection) {
    collection->mStyleRule = nullptr;
    collection->mStyleRuleRefreshTime = TimeStamp();
    collection->UpdateAnimationGeneration(mPresContext);

    // Copy over the start times and (if still paused) pause starts
    // for each animation (matching on name only) that was also in the
    // old list of animations.
    // This means that we honor dynamic changes, which isn't what the
    // spec says to do, but WebKit seems to honor at least some of
    // them.  See
    // http://lists.w3.org/Archives/Public/www-style/2011Apr/0079.html
    // In order to honor what the spec said, we'd copy more data over
    // (or potentially optimize BuildAnimations to avoid rebuilding it
    // in the first place).
    if (!collection->mAnimations.IsEmpty()) {

      for (size_t newIdx = newAnimations.Length(); newIdx-- != 0;) {
        Animation* newAnim = newAnimations[newIdx];

        // Find the matching animation with this name in the old list
        // of animations.  We iterate through both lists in a backwards
        // direction which means that if there are more animations in
        // the new list of animations with a given name than in the old
        // list, it will be the animations towards the of the beginning of
        // the list that do not match and are treated as new animations.
        nsRefPtr<CSSAnimation> oldAnim;
        size_t oldIdx = collection->mAnimations.Length();
        while (oldIdx-- != 0) {
          CSSAnimation* a = collection->mAnimations[oldIdx]->AsCSSAnimation();
          MOZ_ASSERT(a, "All animations in the CSS Animation collection should"
                        " be CSSAnimation objects");
          if (a->Name() == newAnim->Name()) {
            oldAnim = a;
            break;
          }
        }
        if (!oldAnim) {
          continue;
        }

        bool animationChanged = false;

        // Update the old from the new so we can keep the original object
        // identity (and any expando properties attached to it).
        if (oldAnim->GetEffect() && newAnim->GetEffect()) {
          KeyframeEffectReadOnly* oldEffect = oldAnim->GetEffect();
          KeyframeEffectReadOnly* newEffect = newAnim->GetEffect();
          animationChanged =
            oldEffect->Timing() != newEffect->Timing() ||
            oldEffect->Properties() != newEffect->Properties();
          oldEffect->Timing() = newEffect->Timing();
          oldEffect->Properties() = newEffect->Properties();
        }

        // Reset compositor state so animation will be re-synchronized.
//.........这里部分代码省略.........

nsIStyleRule*
nsAnimationManager::CheckAnimationRule(nsStyleContext* aStyleContext,
                                       mozilla::dom::Element* aElement)
{
  // Ignore animations for print or print preview, and for elements
  // that are not attached to the document tree.
  if (!mPresContext->IsDynamic() || !aElement->IsInComposedDoc()) {
    return nullptr;
  }

  // Everything that causes our animation data to change triggers a
  // style change, which in turn triggers a non-animation restyle.
  // Likewise, when we initially construct frames, we're not in a
  // style change, but also not in an animation restyle.

  const nsStyleDisplay* disp = aStyleContext->StyleDisplay();
  AnimationCollection* collection =
    GetAnimationCollection(aElement,
                           aStyleContext->GetPseudoType(),
                           false /* aCreateIfNeeded */);
  if (!collection &&
      disp->mAnimationNameCount == 1 &&
      disp->mAnimations[0].GetName().IsEmpty()) {
    return nullptr;
  }

  nsAutoAnimationMutationBatch mb(aElement->OwnerDoc());

  // build the animations list
  dom::DocumentTimeline* timeline = aElement->OwnerDoc()->Timeline();
  AnimationPtrArray newAnimations;
  if (!aStyleContext->IsInDisplayNoneSubtree()) {
    BuildAnimations(aStyleContext, aElement, timeline, newAnimations);
  }

  if (newAnimations.IsEmpty()) {
    if (collection) {
      collection->Destroy();
    }
    return nullptr;
  }

  if (collection) {
    collection->mStyleRuleRefreshTime = TimeStamp();
    EffectSet* effectSet =
      EffectSet::GetEffectSet(aElement, aStyleContext->GetPseudoType());
    if (effectSet) {
      effectSet->UpdateAnimationGeneration(mPresContext);
    }

    // Copy over the start times and (if still paused) pause starts
    // for each animation (matching on name only) that was also in the
    // old list of animations.
    // This means that we honor dynamic changes, which isn't what the
    // spec says to do, but WebKit seems to honor at least some of
    // them.  See
    // http://lists.w3.org/Archives/Public/www-style/2011Apr/0079.html
    // In order to honor what the spec said, we'd copy more data over
    // (or potentially optimize BuildAnimations to avoid rebuilding it
    // in the first place).
    if (!collection->mAnimations.IsEmpty()) {

      for (size_t newIdx = newAnimations.Length(); newIdx-- != 0;) {
        Animation* newAnim = newAnimations[newIdx];

        // Find the matching animation with this name in the old list
        // of animations.  We iterate through both lists in a backwards
        // direction which means that if there are more animations in
        // the new list of animations with a given name than in the old
        // list, it will be the animations towards the of the beginning of
        // the list that do not match and are treated as new animations.
        RefPtr<CSSAnimation> oldAnim;
        size_t oldIdx = collection->mAnimations.Length();
        while (oldIdx-- != 0) {
          CSSAnimation* a = collection->mAnimations[oldIdx]->AsCSSAnimation();
          MOZ_ASSERT(a, "All animations in the CSS Animation collection should"
                        " be CSSAnimation objects");
          if (a->AnimationName() ==
              newAnim->AsCSSAnimation()->AnimationName()) {
            oldAnim = a;
            break;
          }
        }
        if (!oldAnim) {
          // FIXME: Bug 1134163 - We shouldn't queue animationstart events
          // until the animation is actually ready to run. However, we
          // currently have some tests that assume that these events are
          // dispatched within the same tick as the animation is added
          // so we need to queue up any animationstart events from newly-created
          // animations.
          newAnim->AsCSSAnimation()->QueueEvents();
          continue;
        }

        bool animationChanged = false;

        // Update the old from the new so we can keep the original object
        // identity (and any expando properties attached to it).
        if (oldAnim->GetEffect() && newAnim->GetEffect()) {
          KeyframeEffectReadOnly* oldEffect = oldAnim->GetEffect();
//.........这里部分代码省略.........

Maybe<NonOwningAnimationTarget>
nsNodeUtils::GetTargetForAnimation(const Animation* aAnimation)
{
  KeyframeEffectReadOnly* effect = aAnimation->GetEffect();
  return effect ? effect->GetTarget() : Nothing();
}

void
Animation::ComposeStyle(RefPtr<AnimValuesStyleRule>& aStyleRule,
                        nsCSSPropertyIDSet& aSetProperties)
{
  if (!mEffect) {
    return;
  }

  if (!IsInEffect()) {
    return;
  }

  // In order to prevent flicker, there are a few cases where we want to use
  // a different time for rendering that would otherwise be returned by
  // GetCurrentTime. These are:
  //
  // (a) For animations that are pausing but which are still running on the
  //     compositor. In this case we send a layer transaction that removes the
  //     animation but which also contains the animation values calculated on
  //     the main thread. To prevent flicker when this occurs we want to ensure
  //     the timeline time used to calculate the main thread animation values
  //     does not lag far behind the time used on the compositor. Ideally we
  //     would like to use the "animation ready time" calculated at the end of
  //     the layer transaction as the timeline time but it will be too late to
  //     update the style rule at that point so instead we just use the current
  //     wallclock time.
  //
  // (b) For animations that are pausing that we have already taken off the
  //     compositor. In this case we record a pending ready time but we don't
  //     apply it until the next tick. However, while waiting for the next tick,
  //     we should still use the pending ready time as the timeline time. If we
  //     use the regular timeline time the animation may appear jump backwards
  //     if the main thread's timeline time lags behind the compositor.
  //
  // (c) For animations that are play-pending due to an aborted pause operation
  //     (i.e. a pause operation that was interrupted before we entered the
  //     paused state). When we cancel a pending pause we might momentarily take
  //     the animation off the compositor, only to re-add it moments later. In
  //     that case the compositor might have been ahead of the main thread so we
  //     should use the current wallclock time to ensure the animation doesn't
  //     temporarily jump backwards.
  //
  // To address each of these cases we temporarily tweak the hold time
  // immediately before updating the style rule and then restore it immediately
  // afterwards. This is purely to prevent visual flicker. Other behavior
  // such as dispatching events continues to rely on the regular timeline time.
  AnimationPlayState playState = PlayState();
  {
    AutoRestore<Nullable<TimeDuration>> restoreHoldTime(mHoldTime);

    if (playState == AnimationPlayState::Pending &&
        mHoldTime.IsNull() &&
        !mStartTime.IsNull()) {
      Nullable<TimeDuration> timeToUse = mPendingReadyTime;
      if (timeToUse.IsNull() &&
          mTimeline &&
          mTimeline->TracksWallclockTime()) {
        timeToUse = mTimeline->ToTimelineTime(TimeStamp::Now());
      }
      if (!timeToUse.IsNull()) {
        mHoldTime.SetValue((timeToUse.Value() - mStartTime.Value())
                            .MultDouble(mPlaybackRate));
      }
    }

    KeyframeEffectReadOnly* keyframeEffect = mEffect->AsKeyframeEffect();
    if (keyframeEffect) {
      keyframeEffect->ComposeStyle(aStyleRule, aSetProperties);
    }
  }

  MOZ_ASSERT(playState == PlayState(),
             "Play state should not change during the course of compositing");
  mFinishedAtLastComposeStyle = (playState == AnimationPlayState::Finished);
}