author Brian Birtles <>
Tue, 08 Jan 2019 06:42:17 +0000
changeset 452808 c19867adc2c78839543c18eecd2c6425e736b894
parent 452446 f0a91d36587266d7454a450c6044d573664fbed5
child 452810 5d75876949f3865bfc8f07ed5f9a3607461b1318
permissions -rw-r--r--
Bug 1518374 - Mark GetKeyframes and GetTargetComputedStyle as const; r=hiro Depends on D15899 Differential Revision:

/* -*- 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_KeyframeEffect_h
#define mozilla_dom_KeyframeEffect_h

#include "nsChangeHint.h"
#include "nsCSSPropertyID.h"
#include "nsCSSPropertyIDSet.h"
#include "nsCSSValue.h"
#include "nsCycleCollectionParticipant.h"
#include "nsRefPtrHashtable.h"
#include "nsTArray.h"
#include "nsWrapperCache.h"
#include "mozilla/AnimationPerformanceWarning.h"
#include "mozilla/AnimationPropertySegment.h"
#include "mozilla/AnimationTarget.h"
#include "mozilla/Attributes.h"
#include "mozilla/ComputedTimingFunction.h"
#include "mozilla/EffectCompositor.h"
#include "mozilla/Keyframe.h"
#include "mozilla/KeyframeEffectParams.h"
// RawServoDeclarationBlock and associated RefPtrTraits
#include "mozilla/ServoBindingTypes.h"
#include "mozilla/StyleAnimationValue.h"
#include "mozilla/dom/AnimationEffect.h"
#include "mozilla/dom/BindingDeclarations.h"
#include "mozilla/dom/Element.h"

struct JSContext;
class JSObject;
class nsIContent;
class nsIFrame;
class nsIPresShell;

namespace mozilla {

class AnimValuesStyleRule;
enum class CSSPseudoElementType : uint8_t;
class ErrorResult;
struct AnimationRule;
struct TimingParams;
class EffectSet;
class ComputedStyle;

namespace dom {
class ElementOrCSSPseudoElement;
class GlobalObject;
class OwningElementOrCSSPseudoElement;
class UnrestrictedDoubleOrKeyframeAnimationOptions;
class UnrestrictedDoubleOrKeyframeEffectOptions;
enum class IterationCompositeOperation : uint8_t;
enum class CompositeOperation : uint8_t;
struct AnimationPropertyDetails;
}  // namespace dom

struct AnimationProperty {
  nsCSSPropertyID mProperty = eCSSProperty_UNKNOWN;

  // If true, the propery is currently being animated on the compositor.
  // Note that when the owning Animation requests a non-throttled restyle, in
  // between calling RequestRestyle on its EffectCompositor and when the
  // restyle is performed, this member may temporarily become false even if
  // the animation remains on the layer after the restyle.
  // **NOTE**: This member is not included when comparing AnimationProperty
  // objects for equality.
  bool mIsRunningOnCompositor = false;

  Maybe<AnimationPerformanceWarning> mPerformanceWarning;

  InfallibleTArray<AnimationPropertySegment> mSegments;

  // The copy constructor/assignment doesn't copy mIsRunningOnCompositor and
  // mPerformanceWarning.
  AnimationProperty() = default;
  AnimationProperty(const AnimationProperty& aOther)
      : mProperty(aOther.mProperty), mSegments(aOther.mSegments) {}
  AnimationProperty& operator=(const AnimationProperty& aOther) {
    mProperty = aOther.mProperty;
    mSegments = aOther.mSegments;
    return *this;

  // NOTE: This operator does *not* compare the mIsRunningOnCompositor member.
  // This is because AnimationProperty objects are compared when recreating
  // CSS animations to determine if mutation observer change records need to
  // be created or not. However, at the point when these objects are compared
  // the mIsRunningOnCompositor will not have been set on the new objects so
  // we ignore this member to avoid generating spurious change records.
  bool operator==(const AnimationProperty& aOther) const {
    return mProperty == aOther.mProperty && mSegments == aOther.mSegments;
  bool operator!=(const AnimationProperty& aOther) const {
    return !(*this == aOther);

struct ElementPropertyTransition;

namespace dom {

class Animation;
class Document;

class KeyframeEffect : public AnimationEffect {
  KeyframeEffect(Document* aDocument,
                 const Maybe<OwningAnimationTarget>& aTarget,
                 TimingParams&& aTiming, const KeyframeEffectParams& aOptions);


  virtual JSObject* WrapObject(JSContext* aCx,
                               JS::Handle<JSObject*> aGivenProto) override;

  KeyframeEffect* AsKeyframeEffect() override { return this; }

  // KeyframeEffect interface
  static already_AddRefed<KeyframeEffect> Constructor(
      const GlobalObject& aGlobal,
      const Nullable<ElementOrCSSPseudoElement>& aTarget,
      JS::Handle<JSObject*> aKeyframes,
      const UnrestrictedDoubleOrKeyframeEffectOptions& aOptions,
      ErrorResult& aRv);

  static already_AddRefed<KeyframeEffect> Constructor(
      const GlobalObject& aGlobal, KeyframeEffect& aSource, ErrorResult& aRv);

  // Variant of Constructor that accepts a KeyframeAnimationOptions object
  // for use with for Animatable.animate.
  // Not exposed to content.
  static already_AddRefed<KeyframeEffect> Constructor(
      const GlobalObject& aGlobal,
      const Nullable<ElementOrCSSPseudoElement>& aTarget,
      JS::Handle<JSObject*> aKeyframes,
      const UnrestrictedDoubleOrKeyframeAnimationOptions& aOptions,
      ErrorResult& aRv);

  void GetTarget(Nullable<OwningElementOrCSSPseudoElement>& aRv) const;
  Maybe<NonOwningAnimationTarget> GetTarget() const {
    Maybe<NonOwningAnimationTarget> result;
    if (mTarget) {
    return result;
  // This method calls GetTargetComputedStyle which is not safe to use when
  // we are in the middle of updating style. If we need to use this when
  // updating style, we should pass the ComputedStyle into this method and use
  // that to update the properties rather than calling
  // GetComputedStyle.
  void SetTarget(const Nullable<ElementOrCSSPseudoElement>& aTarget);

  void GetKeyframes(JSContext*& aCx, nsTArray<JSObject*>& aResult,
                    ErrorResult& aRv) const;
  void GetProperties(nsTArray<AnimationPropertyDetails>& aProperties,
                     ErrorResult& aRv) const;

  IterationCompositeOperation IterationComposite() const;
  void SetIterationComposite(
      const IterationCompositeOperation& aIterationComposite);

  CompositeOperation Composite() const;
  void SetComposite(const CompositeOperation& aComposite);

  void NotifySpecifiedTimingUpdated();
  void NotifyAnimationTimingUpdated();
  void RequestRestyle(EffectCompositor::RestyleType aRestyleType);
  void SetAnimation(Animation* aAnimation) override;
  void SetKeyframes(JSContext* aContext, JS::Handle<JSObject*> aKeyframes,
                    ErrorResult& aRv);
  void SetKeyframes(nsTArray<Keyframe>&& aKeyframes,
                    const ComputedStyle* aStyle);

  // Returns true if the effect includes |aProperty| regardless of whether the
  // property is overridden by !important rule.
  bool HasAnimationOfProperty(nsCSSPropertyID aProperty) const;

  // GetEffectiveAnimationOfProperty returns AnimationProperty corresponding
  // to a given CSS property if the effect includes the property and the
  // property is not overridden by !important rules.
  // Also EffectiveAnimationOfProperty returns true under the same condition.
  // |aEffect| should be the EffectSet containing this KeyframeEffect since
  // this function is typically called for all KeyframeEffects on an element
  // so that we can avoid multiple calls of EffectSet::GetEffect().
  // NOTE: We don't currently check for !important rules for properties that
  // can't run on the compositor.
  bool HasEffectiveAnimationOfProperty(nsCSSPropertyID aProperty,
                                       const EffectSet& aEffect) const {
    return GetEffectiveAnimationOfProperty(aProperty, aEffect) != nullptr;
  const AnimationProperty* GetEffectiveAnimationOfProperty(
      nsCSSPropertyID aProperty, const EffectSet& aEffect) const;

  // Returns all the effective animated CSS properties that can be animated on
  // the compositor and are not overridden by a higher cascade level.
  // NOTE: This function is basically called for all KeyframeEffects on an
  // element thus it takes |aEffects| to avoid multiple calls of
  // EffectSet::GetEffect().
  // NOTE(2): This function does NOT check that animations are permitted on
  // |aFrame|. It is the responsibility of the caller to first call
  // EffectCompositor::AllowCompositorAnimationsOnFrame for |aFrame|, or use
  // nsLayoutUtils::GetAnimationPropertiesForCompositor instead.
  nsCSSPropertyIDSet GetPropertiesForCompositor(EffectSet& aEffects,
                                                const nsIFrame* aFrame) const;

  const InfallibleTArray<AnimationProperty>& Properties() const {
    return mProperties;

  // Update |mProperties| by recalculating from |mKeyframes| using
  // |aComputedStyle| to resolve specified values.
  void UpdateProperties(const ComputedStyle* aComputedValues);

  // Update various bits of state related to running ComposeStyle().
  // We need to update this outside ComposeStyle() because we should avoid
  // mutating any state in ComposeStyle() since it might be called during
  // parallel traversal.
  void WillComposeStyle();

  // Updates |aComposeResult| with the animation values produced by this
  // AnimationEffect for the current time except any properties contained
  // in |aPropertiesToSkip|.
  void ComposeStyle(RawServoAnimationValueMap& aComposeResult,
                    const nsCSSPropertyIDSet& aPropertiesToSkip);

  // Returns true if at least one property is being animated on compositor.
  bool IsRunningOnCompositor() const;
  void SetIsRunningOnCompositor(nsCSSPropertyID aProperty, bool aIsRunning);
  void ResetIsRunningOnCompositor();

  // Returns true if this effect, applied to |aFrame|, contains properties
  // that mean we shouldn't run transform compositor animations on this element.
  // For example, if we have an animation of geometric properties like 'left'
  // and 'top' on an element, we force all 'transform' animations running at
  // the same time on the same element to run on the main thread.
  // When returning true, |aPerformanceWarning| stores the reason why
  // we shouldn't run the transform animations.
  bool ShouldBlockAsyncTransformAnimations(
      const nsIFrame* aFrame,
      AnimationPerformanceWarning::Type& aPerformanceWarning /* out */) const;
  bool HasGeometricProperties() const;
  bool AffectsGeometry() const override {
    return GetTarget() && HasGeometricProperties();

  Document* GetRenderedDocument() const;
  nsIPresShell* GetPresShell() const;

  // Associates a warning with the animated property on the specified frame
  // indicating why, for example, the property could not be animated on the
  // compositor. |aParams| and |aParamsLength| are optional parameters which
  // will be used to generate a localized message for devtools.
  void SetPerformanceWarning(nsCSSPropertyID aProperty,
                             const AnimationPerformanceWarning& aWarning);

  // Cumulative change hint on each segment for each property.
  // This is used for deciding the animation is paint-only.
  void CalculateCumulativeChangeHint(const ComputedStyle* aStyle);

  // Returns true if all of animation properties' change hints
  // can ignore painting if the animation is not visible.
  // See nsChangeHint_Hints_CanIgnoreIfNotVisible in nsChangeHint.h
  // in detail which change hint can be ignored.
  bool CanIgnoreIfNotVisible() const;

  // Returns true if the effect is current state and has scale animation.
  // |aFrame| is used for calculation of scale values.
  bool ContainsAnimatedScale(const nsIFrame* aFrame) const;

  AnimationValue BaseStyle(nsCSSPropertyID aProperty) const {
    AnimationValue result;
    bool hasProperty = false;
    // We cannot use getters_AddRefs on RawServoAnimationValue because it is
    // an incomplete type, so Get() doesn't work. Instead, use GetWeak, and
    // then assign the raw pointer to a RefPtr.
    result.mServo = mBaseValues.GetWeak(aProperty, &hasProperty);
    MOZ_ASSERT(hasProperty || result.IsNull());
    return result;

  enum class MatchForCompositor {
    // This animation matches and should run on the compositor if possible.
    // This (not currently playing) animation matches and can be run on the
    // compositor if there are other animations for this property that return
    // 'Yes'.
    // This animation does not match or can't be run on the compositor.
    // This animation does not match or can't be run on the compositor and,
    // furthermore, its presence means we should not run any animations for this
    // property on the compositor.

  MatchForCompositor IsMatchForCompositor(
      nsCSSPropertyID aProperty, const nsIFrame* aFrame,
      const EffectSet& aEffects,
      AnimationPerformanceWarning::Type& aPerformanceWarning /* out */) const;

  static bool HasComputedTimingChanged(
      const ComputedTiming& aComputedTiming,
      IterationCompositeOperation aIterationComposite,
      const Nullable<double>& aProgressOnLastCompose,
      uint64_t aCurrentIterationOnLastCompose);

  ~KeyframeEffect() override = default;

  static Maybe<OwningAnimationTarget> ConvertTarget(
      const Nullable<ElementOrCSSPseudoElement>& aTarget);

  template <class OptionsType>
  static already_AddRefed<KeyframeEffect> ConstructKeyframeEffect(
      const GlobalObject& aGlobal,
      const Nullable<ElementOrCSSPseudoElement>& aTarget,
      JS::Handle<JSObject*> aKeyframes, const OptionsType& aOptions,
      ErrorResult& aRv);

  // Build properties by recalculating from |mKeyframes| using |aComputedStyle|
  // to resolve specified values. This function also applies paced spacing if
  // needed.
  nsTArray<AnimationProperty> BuildProperties(const ComputedStyle* aStyle);

  // This effect is registered with its target element so long as:
  // (a) It has a target element, and
  // (b) It is "relevant" (i.e. yet to finish but not idle, or finished but
  //     filling forwards)
  // As a result, we need to make sure this gets called whenever anything
  // changes with regards to this effects's timing including changes to the
  // owning Animation's timing.
  void UpdateTargetRegistration();

  // Remove the current effect target from its EffectSet.
  void UnregisterTarget();

  // Update the associated frame state bits so that, if necessary, a stacking
  // context will be created and the effect sent to the compositor.  We
  // typically need to do this when the properties referenced by the keyframe
  // have changed, or when the target frame might have changed.
  void MaybeUpdateFrameForCompositor();

  // Looks up the ComputedStyle associated with the target element, if any.
  // We need to be careful to *not* call this when we are updating the style
  // context. That's because calling GetComputedStyle when we are in the process
  // of building a ComputedStyle may trigger various forms of infinite
  // recursion.
  already_AddRefed<ComputedStyle> GetTargetComputedStyle() const;

  // A wrapper for marking cascade update according to the current
  // target and its effectSet.
  void MarkCascadeNeedsUpdate();

  void EnsureBaseStyles(const ComputedStyle* aComputedValues,
                        const nsTArray<AnimationProperty>& aProperties,
                        bool* aBaseStylesChanged);
  void EnsureBaseStyle(const AnimationProperty& aProperty,
                       nsPresContext* aPresContext,
                       const ComputedStyle* aComputedValues,
                       RefPtr<ComputedStyle>& aBaseComputedValues);

  Maybe<OwningAnimationTarget> mTarget;

  KeyframeEffectParams mEffectOptions;

  // The specified keyframes.
  nsTArray<Keyframe> mKeyframes;

  // A set of per-property value arrays, derived from |mKeyframes|.
  nsTArray<AnimationProperty> mProperties;

  // The computed progress last time we composed the style rule. This is
  // used to detect when the progress is not changing (e.g. due to a step
  // timing function) so we can avoid unnecessary style updates.
  Nullable<double> mProgressOnLastCompose;

  // The purpose of this value is the same as mProgressOnLastCompose but
  // this is used to detect when the current iteration is not changing
  // in the case when iterationComposite is accumulate.
  uint64_t mCurrentIterationOnLastCompose = 0;

  // We need to track when we go to or from being "in effect" since
  // we need to re-evaluate the cascade of animations when that changes.
  bool mInEffectOnLastAnimationTimingUpdate;

  // The non-animated values for properties in this effect that contain at
  // least one animation value that is composited with the underlying value
  // (i.e. it uses the additive or accumulate composite mode).
  using BaseValuesHashmap =
      nsRefPtrHashtable<nsUint32HashKey, RawServoAnimationValue>;
  BaseValuesHashmap mBaseValues;

  // True if this effect is in the EffectSet for its target element. This is
  // used as an optimization to avoid unnecessary hashmap lookups on the
  // EffectSet.
  bool mInEffectSet = false;

  nsChangeHint mCumulativeChangeHint;

  void ComposeStyleRule(RawServoAnimationValueMap& aAnimationValues,
                        const AnimationProperty& aProperty,
                        const AnimationPropertySegment& aSegment,
                        const ComputedTiming& aComputedTiming);

  already_AddRefed<ComputedStyle> CreateComputedStyleForAnimationValue(
      nsCSSPropertyID aProperty, const AnimationValue& aValue,
      nsPresContext* aPresContext, const ComputedStyle* aBaseComputedStyle);

  // Return the primary frame for the target (pseudo-)element.
  nsIFrame* GetPrimaryFrame() const;
  // Returns the frame which is used for styling.
  nsIFrame* GetStyleFrame() const;

  bool CanThrottle() const;
  bool CanThrottleOverflowChanges(const nsIFrame& aFrame) const;
  bool CanThrottleOverflowChangesInScrollable(nsIFrame& aFrame) const;
  bool CanThrottleIfNotVisible(nsIFrame& aFrame) const;

  // Returns true if the computedTiming has changed since the last
  // composition.
  bool HasComputedTimingChanged() const;

  // Returns true unless Gecko limitations prevent performing transform
  // animations for |aFrame|. When returning true, the reason for the
  // limitation is stored in |aOutPerformanceWarning|.
  static bool CanAnimateTransformOnCompositor(
      const nsIFrame* aFrame,
      AnimationPerformanceWarning::Type& aPerformanceWarning /* out */);
  static bool IsGeometricProperty(const nsCSSPropertyID aProperty);

  static const TimeDuration OverflowRegionRefreshInterval();

  void UpdateEffectSet(mozilla::EffectSet* aEffectSet = nullptr) const;

  // Returns true if this effect has properties that might affect the overflow
  // region.
  // This function is used for updating scroll bars or notifying intersection
  // observers reflected by the transform.
  bool HasPropertiesThatMightAffectOverflow() const {
    return mCumulativeChangeHint &
           (nsChangeHint_AddOrRemoveTransform | nsChangeHint_UpdateOverflow |
            nsChangeHint_UpdatePostTransformOverflow |

  // Returns true if this effect causes visibility change.
  // (i.e. 'visibility: hidden' -> 'visibility: visible' and vice versa.)
  bool HasVisibilityChange() const {
    return mCumulativeChangeHint & nsChangeHint_VisibilityChange;

}  // namespace dom
}  // namespace mozilla

#endif  // mozilla_dom_KeyframeEffect_h