Magic-Mirror/gecko-dev
1
0
Fork 0
mirror of https://github.com/mozilla/gecko-dev.git synced 2024-12-14 10:43:24 +00:00
Code Issues Actions Packages Projects Releases Wiki Activity
1a49c35a07
gecko-dev/layout/style/nsAnimationManager.cpp
Hiroyuki Ikezoe 2b220f490f Bug 1285407 - Part 3: Remove UpdateCascadeResults call because it's called against the same nsStyleContext from MaybeUpdateAnimationRule. r=birtles 
MozReview-Commit-ID: FrrFLq9S2f4

--HG--
extra : rebase_source : 20d9329b0b801fa78cf8889f404a6cc0ac011a69
2016-07-11 17:28:17 +09:00

1096 lines
38 KiB
C++
Raw Blame History

/* vim: set shiftwidth=2 tabstop=8 autoindent cindent expandtab: */
/* 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/. */
#include "nsAnimationManager.h"
#include "nsTransitionManager.h"
#include "mozilla/dom/CSSAnimationBinding.h"
#include "mozilla/EffectCompositor.h"
#include "mozilla/EffectSet.h"
#include "mozilla/MemoryReporting.h"
#include "mozilla/StyleAnimationValue.h"
#include "mozilla/dom/DocumentTimeline.h"
#include "mozilla/dom/KeyframeEffect.h"
#include "nsPresContext.h"
#include "nsStyleSet.h"
#include "nsStyleChangeList.h"
#include "nsCSSRules.h"
#include "mozilla/RestyleManager.h"
#include "nsLayoutUtils.h"
#include "nsIFrame.h"
#include "nsIDocument.h"
#include "nsDOMMutationObserver.h"
#include <algorithm> // std::stable_sort
#include <math.h>
using namespace mozilla;
using namespace mozilla::css;
using mozilla::dom::Animation;
using mozilla::dom::AnimationPlayState;
using mozilla::dom::KeyframeEffectReadOnly;
using mozilla::dom::CSSAnimation;
namespace {
// Pair of an event message and elapsed time used when determining the set of
// events to queue.
typedef Pair<EventMessage, StickyTimeDuration> EventPair;
} // anonymous namespace
////////////////////////// CSSAnimation ////////////////////////////
JSObject*
CSSAnimation::WrapObject(JSContext* aCx, JS::Handle<JSObject*> aGivenProto)
{
return dom::CSSAnimationBinding::Wrap(aCx, this, aGivenProto);
}
mozilla::dom::Promise*
CSSAnimation::GetReady(ErrorResult& aRv)
{
FlushStyle();
return Animation::GetReady(aRv);
}
void
CSSAnimation::Play(ErrorResult &aRv, LimitBehavior aLimitBehavior)
{
mPauseShouldStick = false;
Animation::Play(aRv, aLimitBehavior);
}
void
CSSAnimation::Pause(ErrorResult& aRv)
{
mPauseShouldStick = true;
Animation::Pause(aRv);
}
AnimationPlayState
CSSAnimation::PlayStateFromJS() const
{
// Flush style to ensure that any properties controlling animation state
// (e.g. animation-play-state) are fully updated.
FlushStyle();
return Animation::PlayStateFromJS();
}
void
CSSAnimation::PlayFromJS(ErrorResult& aRv)
{
// Note that flushing style below might trigger calls to
// PlayFromStyle()/PauseFromStyle() on this object.
FlushStyle();
Animation::PlayFromJS(aRv);
}
void
CSSAnimation::PlayFromStyle()
{
mIsStylePaused = false;
if (!mPauseShouldStick) {
ErrorResult rv;
PlayNoUpdate(rv, Animation::LimitBehavior::Continue);
// play() should not throw when LimitBehavior is Continue
MOZ_ASSERT(!rv.Failed(), "Unexpected exception playing animation");
}
}
void
CSSAnimation::PauseFromStyle()
{
// Check if the pause state is being overridden
if (mIsStylePaused) {
return;
}
mIsStylePaused = true;
ErrorResult rv;
PauseNoUpdate(rv);
// pause() should only throw when *all* of the following conditions are true:
// - we are in the idle state, and
// - we have a negative playback rate, and
// - we have an infinitely repeating animation
// The first two conditions will never happen under regular style processing
// but could happen if an author made modifications to the Animation object
// and then updated animation-play-state. It's an unusual case and there's
// no obvious way to pass on the exception information so we just silently
// fail for now.
if (rv.Failed()) {
NS_WARNING("Unexpected exception pausing animation - silently failing");
}
}
void
CSSAnimation::Tick()
{
Animation::Tick();
QueueEvents();
}
bool
CSSAnimation::HasLowerCompositeOrderThan(const CSSAnimation& aOther) const
{
MOZ_ASSERT(IsTiedToMarkup() && aOther.IsTiedToMarkup(),
"Should only be called for CSS animations that are sorted "
"as CSS animations (i.e. tied to CSS markup)");
// 0. Object-equality case
if (&aOther == this) {
return false;
}
// 1. Sort by document order
if (!mOwningElement.Equals(aOther.mOwningElement)) {
return mOwningElement.LessThan(aOther.mOwningElement);
}
// 2. (Same element and pseudo): Sort by position in animation-name
return mAnimationIndex < aOther.mAnimationIndex;
}
void
CSSAnimation::QueueEvents()
{
if (!mEffect) {
return;
}
// If the animation is pending, we ignore animation events until we finish
// pending.
if (mPendingState != PendingState::NotPending) {
return;
}
// CSS animations dispatch events at their owning element. This allows
// script to repurpose a CSS animation to target a different element,
// to use a group effect (which has no obvious "target element"), or
// to remove the animation effect altogether whilst still getting
// animation events.
//
// It does mean, however, that for a CSS animation that has no owning
// element (e.g. it was created using the CSSAnimation constructor or
// disassociated from CSS) no events are fired. If it becomes desirable
// for these animations to still fire events we should spec the concept
// of the "original owning element" or "event target" and allow script
// to set it when creating a CSSAnimation object.
if (!mOwningElement.IsSet()) {
return;
}
dom::Element* owningElement;
CSSPseudoElementType owningPseudoType;
mOwningElement.GetElement(owningElement, owningPseudoType);
MOZ_ASSERT(owningElement, "Owning element should be set");
// Get the nsAnimationManager so we can queue events on it
nsPresContext* presContext = mOwningElement.GetRenderedPresContext();
if (!presContext) {
return;
}
nsAnimationManager* manager = presContext->AnimationManager();
ComputedTiming computedTiming = mEffect->GetComputedTiming();
if (computedTiming.mPhase == ComputedTiming::AnimationPhase::Null) {
return; // do nothing
}
// Note that script can change the start time, so we have to handle moving
// backwards through the animation as well as forwards. An 'animationstart'
// is dispatched if we enter the active phase (regardless if that is from
// before or after the animation's active phase). An 'animationend' is
// dispatched if we leave the active phase (regardless if that is to before
// or after the animation's active phase).
bool wasActive = mPreviousPhaseOrIteration != PREVIOUS_PHASE_BEFORE &&
mPreviousPhaseOrIteration != PREVIOUS_PHASE_AFTER;
bool isActive =
computedTiming.mPhase == ComputedTiming::AnimationPhase::Active;
bool isSameIteration =
computedTiming.mCurrentIteration == mPreviousPhaseOrIteration;
bool skippedActivePhase =
(mPreviousPhaseOrIteration == PREVIOUS_PHASE_BEFORE &&
computedTiming.mPhase == ComputedTiming::AnimationPhase::After) ||
(mPreviousPhaseOrIteration == PREVIOUS_PHASE_AFTER &&
computedTiming.mPhase == ComputedTiming::AnimationPhase::Before);
bool skippedFirstIteration =
isActive &&
mPreviousPhaseOrIteration == PREVIOUS_PHASE_BEFORE &&
computedTiming.mCurrentIteration > 0;
MOZ_ASSERT(!skippedActivePhase || (!isActive && !wasActive),
"skippedActivePhase only makes sense if we were & are inactive");
if (computedTiming.mPhase == ComputedTiming::AnimationPhase::Before) {
mPreviousPhaseOrIteration = PREVIOUS_PHASE_BEFORE;
} else if (computedTiming.mPhase == ComputedTiming::AnimationPhase::Active) {
mPreviousPhaseOrIteration = computedTiming.mCurrentIteration;
} else if (computedTiming.mPhase == ComputedTiming::AnimationPhase::After) {
mPreviousPhaseOrIteration = PREVIOUS_PHASE_AFTER;
}
AutoTArray<EventPair, 2> events;
StickyTimeDuration initialAdvance = StickyTimeDuration(InitialAdvance());
StickyTimeDuration iterationStart = computedTiming.mDuration *
computedTiming.mCurrentIteration;
const StickyTimeDuration& activeDuration = computedTiming.mActiveDuration;
if (skippedFirstIteration) {
// Notify animationstart and animationiteration in same tick.
events.AppendElement(EventPair(eAnimationStart, initialAdvance));
events.AppendElement(EventPair(eAnimationIteration,
std::max(iterationStart, initialAdvance)));
} else if (!wasActive && isActive) {
events.AppendElement(EventPair(eAnimationStart, initialAdvance));
} else if (wasActive && !isActive) {
events.AppendElement(EventPair(eAnimationEnd, activeDuration));
} else if (wasActive && isActive && !isSameIteration) {
events.AppendElement(EventPair(eAnimationIteration, iterationStart));
} else if (skippedActivePhase) {
events.AppendElement(EventPair(eAnimationStart,
std::min(initialAdvance, activeDuration)));
events.AppendElement(EventPair(eAnimationEnd, activeDuration));
} else {
return; // No events need to be sent
}
for (const EventPair& pair : events){
manager->QueueEvent(
AnimationEventInfo(owningElement, owningPseudoType,
pair.first(), mAnimationName,
pair.second(),
ElapsedTimeToTimeStamp(pair.second()),
this));
}
}
void
CSSAnimation::UpdateTiming(SeekFlag aSeekFlag, SyncNotifyFlag aSyncNotifyFlag)
{
if (mNeedsNewAnimationIndexWhenRun &&
PlayState() != AnimationPlayState::Idle) {
mAnimationIndex = sNextAnimationIndex++;
mNeedsNewAnimationIndexWhenRun = false;
}
Animation::UpdateTiming(aSeekFlag, aSyncNotifyFlag);
}
TimeStamp
CSSAnimation::ElapsedTimeToTimeStamp(const StickyTimeDuration&
aElapsedTime) const
{
return AnimationTimeToTimeStamp(aElapsedTime +
mEffect->SpecifiedTiming().mDelay);
}
////////////////////////// nsAnimationManager ////////////////////////////
NS_IMPL_CYCLE_COLLECTION(nsAnimationManager, mEventDispatcher)
NS_IMPL_CYCLE_COLLECTION_ROOT_NATIVE(nsAnimationManager, AddRef)
NS_IMPL_CYCLE_COLLECTION_UNROOT_NATIVE(nsAnimationManager, Release)
// Find the matching animation by |aName| in the old list
// of animations and remove the matched animation from the list.
static already_AddRefed<CSSAnimation>
PopExistingAnimation(const nsAString& aName,
nsAnimationManager::CSSAnimationCollection* aCollection)
{
if (!aCollection) {
return nullptr;
}
// Animations are stored in reverse order to how they appear in the
// animation-name property. However, we want to match animations beginning
// from the end of the animation-name list, so we iterate *forwards*
// through the collection.
for (size_t idx = 0, length = aCollection->mAnimations.Length();
idx != length; ++ idx) {
CSSAnimation* cssAnim = aCollection->mAnimations[idx];
if (cssAnim->AnimationName() == aName) {
RefPtr<CSSAnimation> match = cssAnim;
aCollection->mAnimations.RemoveElementAt(idx);
return match.forget();
}
}
return nullptr;
}
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()) {
KeyframeEffectReadOnly* oldEffect = aOld.GetEffect();
animationChanged =
oldEffect->SpecifiedTiming() != aNewTiming;
oldEffect->SetSpecifiedTiming(aNewTiming);
oldEffect->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);
}
}
void
nsAnimationManager::UpdateAnimations(nsStyleContext* aStyleContext,
mozilla::dom::Element* aElement)
{
MOZ_ASSERT(mPresContext->IsDynamic(),
"Should not update animations for print or print preview");
MOZ_ASSERT(aElement->IsInComposedDoc(),
"Should not update animations that are not attached to the "
"document tree");
// 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();
CSSAnimationCollection* collection =
CSSAnimationCollection::GetAnimationCollection(aElement,
aStyleContext->
GetPseudoType());
if (!collection &&
disp->mAnimationNameCount == 1 &&
disp->mAnimations[0].GetName().IsEmpty()) {
return;
}
nsAutoAnimationMutationBatch mb(aElement->OwnerDoc());
// Build the updated animations list, extracting matching animations from
// the existing collection as we go.
OwningCSSAnimationPtrArray newAnimations;
if (!aStyleContext->IsInDisplayNoneSubtree()) {
BuildAnimations(aStyleContext, aElement, collection, newAnimations);
}
if (newAnimations.IsEmpty()) {
if (collection) {
collection->Destroy();
}
return;
}
if (collection) {
EffectSet* effectSet =
EffectSet::GetEffectSet(aElement, aStyleContext->GetPseudoType());
if (effectSet) {
effectSet->UpdateAnimationGeneration(mPresContext);
}
} else {
bool createdCollection = false;
collection =
CSSAnimationCollection::GetOrCreateAnimationCollection(
aElement, aStyleContext->GetPseudoType(), &createdCollection);
if (!collection) {
MOZ_ASSERT(!createdCollection, "outparam should agree with return value");
NS_WARNING("allocating collection failed");
return;
}
if (createdCollection) {
AddElementCollection(collection);
}
}
collection->mAnimations.SwapElements(newAnimations);
// Cancel removed animations
for (size_t newAnimIdx = newAnimations.Length(); newAnimIdx-- != 0; ) {
newAnimations[newAnimIdx]->CancelFromStyle();
}
mPresContext->EffectCompositor()->
MaybeUpdateAnimationRule(aElement,
aStyleContext->GetPseudoType(),
EffectCompositor::CascadeLevel::Animations,
aStyleContext);
// We don't actually dispatch the pending events now. We'll either
// dispatch them the next time we get a refresh driver notification
// or the next time somebody calls
// nsPresShell::FlushPendingNotifications.
if (mEventDispatcher.HasQueuedEvents()) {
mPresContext->Document()->SetNeedStyleFlush();
}
}
void
nsAnimationManager::StopAnimationsForElement(
mozilla::dom::Element* aElement,
mozilla::CSSPseudoElementType aPseudoType)
{
MOZ_ASSERT(aElement);
CSSAnimationCollection* collection =
CSSAnimationCollection::GetAnimationCollection(aElement, aPseudoType);
if (!collection) {
return;
}
nsAutoAnimationMutationBatch mb(aElement->OwnerDoc());
collection->Destroy();
}
class ResolvedStyleCache {
public:
ResolvedStyleCache() : mCache() {}
nsStyleContext* Get(nsPresContext *aPresContext,
nsStyleContext *aParentStyleContext,
Declaration* aKeyframeDeclaration);
private:
nsRefPtrHashtable<nsPtrHashKey<Declaration>, nsStyleContext> mCache;
};
nsStyleContext*
ResolvedStyleCache::Get(nsPresContext *aPresContext,
nsStyleContext *aParentStyleContext,
Declaration* aKeyframeDeclaration)
{
// FIXME (spec): The css3-animations spec isn't very clear about how
// properties are resolved when they have values that depend on other
// properties (e.g., values in 'em'). I presume that they're resolved
// relative to the other styles of the element. The question is
// whether they are resolved relative to other animations: I assume
// that they're not, since that would prevent us from caching a lot of
// data that we'd really like to cache (in particular, the
// StyleAnimationValue values in AnimationPropertySegment).
nsStyleContext *result = mCache.GetWeak(aKeyframeDeclaration);
if (!result) {
aKeyframeDeclaration->SetImmutable();
// The spec says that !important declarations should just be ignored
MOZ_ASSERT(!aKeyframeDeclaration->HasImportantData(),
"Keyframe rule has !important data");
nsCOMArray<nsIStyleRule> rules;
rules.AppendObject(aKeyframeDeclaration);
MOZ_ASSERT(aPresContext->StyleSet()->IsGecko(),
"ServoStyleSet should not use nsAnimationManager for "
"animations");
RefPtr<nsStyleContext> resultStrong = aPresContext->StyleSet()->AsGecko()->
ResolveStyleByAddingRules(aParentStyleContext, rules);
mCache.Put(aKeyframeDeclaration, resultStrong);
result = resultStrong;
}
return result;
}
class MOZ_STACK_CLASS CSSAnimationBuilder final {
public:
CSSAnimationBuilder(nsStyleContext* aStyleContext,
dom::Element* aTarget,
nsAnimationManager::CSSAnimationCollection* aCollection)
: mStyleContext(aStyleContext)
, mTarget(aTarget)
, mCollection(aCollection)
{
MOZ_ASSERT(aStyleContext);
MOZ_ASSERT(aTarget);
mTimeline = mTarget->OwnerDoc()->Timeline();
}
// Returns a new animation set up with given StyleAnimation and
// keyframe rules.
// Or returns an existing animation matching StyleAnimation's name updated
// with the new StyleAnimation and keyframe rules.
already_AddRefed<CSSAnimation>
Build(nsPresContext* aPresContext,
const StyleAnimation& aSrc,
const nsCSSKeyframesRule* aRule);
private:
nsTArray<Keyframe> BuildAnimationFrames(nsPresContext* aPresContext,
const StyleAnimation& aSrc,
const nsCSSKeyframesRule* aRule);
Maybe<ComputedTimingFunction> GetKeyframeTimingFunction(
nsPresContext* aPresContext,
nsCSSKeyframeRule* aKeyframeRule,
const Maybe<ComputedTimingFunction>& aInheritedTimingFunction);
nsTArray<PropertyValuePair> GetKeyframePropertyValues(
nsPresContext* aPresContext,
nsCSSKeyframeRule* aKeyframeRule,
nsCSSPropertySet& aAnimatedProperties);
void FillInMissingKeyframeValues(
nsPresContext* aPresContext,
nsCSSPropertySet aAnimatedProperties,
nsCSSPropertySet aPropertiesSetAtStart,
nsCSSPropertySet aPropertiesSetAtEnd,
const Maybe<ComputedTimingFunction>& aInheritedTimingFunction,
nsTArray<Keyframe>& aKeyframes);
void AppendProperty(nsPresContext* aPresContext,
nsCSSProperty aProperty,
nsTArray<PropertyValuePair>& aPropertyValues);
nsCSSValue GetComputedValue(nsPresContext* aPresContext,
nsCSSProperty aProperty);
static TimingParams TimingParamsFrom(
const StyleAnimation& aStyleAnimation)
{
TimingParams timing;
timing.mDuration.emplace(StickyTimeDuration::FromMilliseconds(
aStyleAnimation.GetDuration()));
timing.mDelay = TimeDuration::FromMilliseconds(aStyleAnimation.GetDelay());
timing.mIterations = aStyleAnimation.GetIterationCount();
MOZ_ASSERT(timing.mIterations >= 0.0 && !IsNaN(timing.mIterations),
"mIterations should be nonnegative & finite, as ensured by "
"CSSParser");
timing.mDirection = aStyleAnimation.GetDirection();
timing.mFill = aStyleAnimation.GetFillMode();
return timing;
}
RefPtr<nsStyleContext> mStyleContext;
RefPtr<dom::Element> mTarget;
RefPtr<dom::DocumentTimeline> mTimeline;
ResolvedStyleCache mResolvedStyles;
RefPtr<nsStyleContext> mStyleWithoutAnimation;
// Existing collection, nullptr if the target element has no animations.
nsAnimationManager::CSSAnimationCollection* mCollection;
};
static Maybe<ComputedTimingFunction>
ConvertTimingFunction(const nsTimingFunction& aTimingFunction);
already_AddRefed<CSSAnimation>
CSSAnimationBuilder::Build(nsPresContext* aPresContext,
const StyleAnimation& aSrc,
const nsCSSKeyframesRule* aRule)
{
MOZ_ASSERT(aPresContext);
MOZ_ASSERT(aRule);
TimingParams timing = TimingParamsFrom(aSrc);
nsTArray<Keyframe> keyframes =
BuildAnimationFrames(aPresContext, aSrc, aRule);
bool isStylePaused =
aSrc.GetPlayState() == NS_STYLE_ANIMATION_PLAY_STATE_PAUSED;
// Find the matching animation with animation name in the old list
// of animations and remove the matched animation from the list.
RefPtr<CSSAnimation> oldAnim =
PopExistingAnimation(aSrc.GetName(), mCollection);
if (oldAnim) {
// 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.
UpdateOldAnimationPropertiesWithNew(*oldAnim,
timing,
keyframes,
isStylePaused,
mStyleContext);
return oldAnim.forget();
}
// mTarget is non-null here, so we emplace it directly.
Maybe<OwningAnimationTarget> target;
target.emplace(mTarget, mStyleContext->GetPseudoType());
KeyframeEffectParams effectOptions;
RefPtr<KeyframeEffectReadOnly> effect =
new KeyframeEffectReadOnly(aPresContext->Document(), target, timing,
effectOptions);
effect->SetKeyframes(Move(keyframes), mStyleContext);
RefPtr<CSSAnimation> animation =
new CSSAnimation(aPresContext->Document()->GetScopeObject(),
aSrc.GetName());
animation->SetOwningElement(
OwningElementRef(*mTarget, mStyleContext->GetPseudoType()));
animation->SetTimelineNoUpdate(mTimeline);
animation->SetEffect(effect);
if (isStylePaused) {
animation->PauseFromStyle();
} else {
animation->PlayFromStyle();
}
return animation.forget();
}
nsTArray<Keyframe>
CSSAnimationBuilder::BuildAnimationFrames(nsPresContext* aPresContext,
const StyleAnimation& aSrc,
const nsCSSKeyframesRule* aRule)
{
// Ideally we'd like to build up a set of Keyframe objects that more-or-less
// reflect the keyframes as-specified in the @keyframes rule(s) so that
// authors get something intuitive when they call anim.effect.getKeyframes().
//
// That, however, proves to be difficult because the way CSS declarations are
// processed differs from how we are able to represent keyframes as
// JavaScript objects in the Web Animations API.
//
// For example,
//
// { margin: 10px; margin-left: 20px }
//
// could be represented as:
//
// { margin: '10px', marginLeft: '20px' }
//
// BUT:
//
// { margin-left: 20px; margin: 10px }
//
// would be represented as:
//
// { margin: '10px' }
//
// Likewise,
//
// { margin-left: 20px; margin-left: 30px }
//
// would be represented as:
//
// { marginLeft: '30px' }
//
// As such, the mapping between source @keyframes and the Keyframe objects
// becomes obscured. The deviation is even more significant when we consider
// cascading between @keyframes rules and variable references in shorthand
// properties.
//
// We could, perhaps, produce a mapping that makes sense most of the time
// but it would be complex and need to be specified and implemented
// interoperably. Instead, for now, for CSS Animations (and CSS Transitions,
// for that matter) we resolve values on @keyframes down to computed values
// (thereby expanding shorthands and variable references) and then pick up the
// last value for each longhand property at each offset.
// FIXME: There is a pending spec change to make multiple @keyframes
// rules with the same name cascade but we don't support that yet.
Maybe<ComputedTimingFunction> inheritedTimingFunction =
ConvertTimingFunction(aSrc.GetTimingFunction());
// First, make up Keyframe objects for each rule
nsTArray<Keyframe> keyframes;
nsCSSPropertySet animatedProperties;
for (auto ruleIdx = 0, ruleEnd = aRule->StyleRuleCount();
ruleIdx != ruleEnd; ++ruleIdx) {
css::Rule* cssRule = aRule->GetStyleRuleAt(ruleIdx);
MOZ_ASSERT(cssRule, "must have rule");
MOZ_ASSERT(cssRule->GetType() == css::Rule::KEYFRAME_RULE,
"must be keyframe rule");
nsCSSKeyframeRule* keyframeRule = static_cast<nsCSSKeyframeRule*>(cssRule);
const nsTArray<float>& keys = keyframeRule->GetKeys();
for (float key : keys) {
if (key < 0.0f || key > 1.0f) {
continue;
}
Keyframe keyframe;
keyframe.mOffset.emplace(key);
keyframe.mTimingFunction =
GetKeyframeTimingFunction(aPresContext, keyframeRule,
inheritedTimingFunction);
keyframe.mPropertyValues =
GetKeyframePropertyValues(aPresContext, keyframeRule,
animatedProperties);
keyframes.AppendElement(Move(keyframe));
}
}
// Next, stable sort by offset
std::stable_sort(keyframes.begin(), keyframes.end(),
[](const Keyframe& a, const Keyframe& b)
{
return a.mOffset < b.mOffset;
});
// Then walk backwards through the keyframes and drop overridden properties.
nsCSSPropertySet propertiesSetAtCurrentOffset;
nsCSSPropertySet propertiesSetAtStart;
nsCSSPropertySet propertiesSetAtEnd;
double currentOffset = -1.0;
for (size_t keyframeIdx = keyframes.Length();
keyframeIdx > 0;
--keyframeIdx) {
Keyframe& keyframe = keyframes[keyframeIdx - 1];
MOZ_ASSERT(keyframe.mOffset, "Should have filled in the offset");
if (keyframe.mOffset.value() != currentOffset) {
propertiesSetAtCurrentOffset.Empty();
currentOffset = keyframe.mOffset.value();
}
// Get the set of properties from this keyframe that have not
// already been set at this offset.
nsTArray<PropertyValuePair> uniquePropertyValues;
uniquePropertyValues.SetCapacity(keyframe.mPropertyValues.Length());
for (const PropertyValuePair& pair : keyframe.mPropertyValues) {
if (!propertiesSetAtCurrentOffset.HasProperty(pair.mProperty)) {
uniquePropertyValues.AppendElement(pair);
propertiesSetAtCurrentOffset.AddProperty(pair.mProperty);
if (currentOffset == 0.0) {
propertiesSetAtStart.AddProperty(pair.mProperty);
} else if (currentOffset == 1.0) {
propertiesSetAtEnd.AddProperty(pair.mProperty);
}
}
}
// If we have a keyframe at the same offset with the same timing
// function we should merge our (unique) values into it.
// Otherwise, we should update the existing keyframe with only the
// unique properties.
//
// Bug 1216843: We should also match composite modes here.
Keyframe* existingKeyframe = nullptr;
// Don't bother searching for an existing keyframe if we don't
// have anything to contribute to it.
if (!uniquePropertyValues.IsEmpty()) {
for (size_t i = keyframeIdx; i < keyframes.Length(); i++) {
Keyframe& kf = keyframes[i];
if (kf.mOffset.value() != currentOffset) {
break;
}
if (kf.mTimingFunction == keyframe.mTimingFunction) {
existingKeyframe = &kf;
break;
}
}
}
if (existingKeyframe) {
existingKeyframe->
mPropertyValues.AppendElements(Move(uniquePropertyValues));
keyframe.mPropertyValues.Clear();
} else {
keyframe.mPropertyValues.SwapElements(uniquePropertyValues);
}
// Check for a now-empty keyframe
if (keyframe.mPropertyValues.IsEmpty()) {
keyframes.RemoveElementAt(keyframeIdx - 1);
// existingKeyframe might dangle now
}
}
// Finally, we need to look for any animated properties that have an
// implicit 'to' or 'from' value and fill in the appropriate keyframe
// with the current computed style.
FillInMissingKeyframeValues(aPresContext, animatedProperties,
propertiesSetAtStart, propertiesSetAtEnd,
inheritedTimingFunction, keyframes);
return keyframes;
}
Maybe<ComputedTimingFunction>
CSSAnimationBuilder::GetKeyframeTimingFunction(
nsPresContext* aPresContext,
nsCSSKeyframeRule* aKeyframeRule,
const Maybe<ComputedTimingFunction>& aInheritedTimingFunction)
{
Maybe<ComputedTimingFunction> result;
if (aKeyframeRule->Declaration() &&
aKeyframeRule->Declaration()->HasProperty(
eCSSProperty_animation_timing_function)) {
RefPtr<nsStyleContext> keyframeRuleContext =
mResolvedStyles.Get(aPresContext, mStyleContext,
aKeyframeRule->Declaration());
const nsTimingFunction& tf = keyframeRuleContext->StyleDisplay()->
mAnimations[0].GetTimingFunction();
result = ConvertTimingFunction(tf);
} else {
result = aInheritedTimingFunction;
}
return result;
}
static Maybe<ComputedTimingFunction>
ConvertTimingFunction(const nsTimingFunction& aTimingFunction)
{
Maybe<ComputedTimingFunction> result;
if (aTimingFunction.mType != nsTimingFunction::Type::Linear) {
result.emplace();
result->Init(aTimingFunction);
}
return result;
}
nsTArray<PropertyValuePair>
CSSAnimationBuilder::GetKeyframePropertyValues(
nsPresContext* aPresContext,
nsCSSKeyframeRule* aKeyframeRule,
nsCSSPropertySet& aAnimatedProperties)
{
nsTArray<PropertyValuePair> result;
RefPtr<nsStyleContext> styleContext =
mResolvedStyles.Get(aPresContext, mStyleContext,
aKeyframeRule->Declaration());
for (nsCSSProperty prop = nsCSSProperty(0);
prop < eCSSProperty_COUNT_no_shorthands;
prop = nsCSSProperty(prop + 1)) {
if (nsCSSProps::kAnimTypeTable[prop] == eStyleAnimType_None ||
!aKeyframeRule->Declaration()->HasNonImportantValueFor(prop)) {
continue;
}
PropertyValuePair pair;
pair.mProperty = prop;
StyleAnimationValue computedValue;
if (!StyleAnimationValue::ExtractComputedValue(prop, styleContext,
computedValue)) {
continue;
}
DebugOnly<bool> uncomputeResult =
StyleAnimationValue::UncomputeValue(prop, Move(computedValue),
pair.mValue);
MOZ_ASSERT(uncomputeResult,
"Unable to get specified value from computed value");
MOZ_ASSERT(pair.mValue.GetUnit() != eCSSUnit_Null,
"Not expecting to read invalid properties");
result.AppendElement(Move(pair));
aAnimatedProperties.AddProperty(prop);
}
return result;
}
// Utility function to walk through |aIter| to find the Keyframe with
// matching offset and timing function but stopping as soon as the offset
// differs from |aOffset| (i.e. it assumes a sorted iterator).
//
// If a matching Keyframe is found,
// Returns true and sets |aIndex| to the index of the matching Keyframe
// within |aIter|.
//
// If no matching Keyframe is found,
// Returns false and sets |aIndex| to the index in the iterator of the
// first Keyframe with an offset differing to |aOffset| or, if the end
// of the iterator is reached, sets |aIndex| to the index after the last
// Keyframe.
template <class IterType>
static bool
FindMatchingKeyframe(
IterType&& aIter,
double aOffset,
const Maybe<ComputedTimingFunction>& aTimingFunctionToMatch,
size_t& aIndex)
{
aIndex = 0;
for (Keyframe& keyframe : aIter) {
if (keyframe.mOffset.value() != aOffset) {
break;
}
if (keyframe.mTimingFunction == aTimingFunctionToMatch) {
return true;
}
++aIndex;
}
return false;
}
void
CSSAnimationBuilder::FillInMissingKeyframeValues(
nsPresContext* aPresContext,
nsCSSPropertySet aAnimatedProperties,
nsCSSPropertySet aPropertiesSetAtStart,
nsCSSPropertySet aPropertiesSetAtEnd,
const Maybe<ComputedTimingFunction>& aInheritedTimingFunction,
nsTArray<Keyframe>& aKeyframes)
{
static const size_t kNotSet = static_cast<size_t>(-1);
// Find/create the keyframe to add start values to
size_t startKeyframeIndex = kNotSet;
if (!aAnimatedProperties.Equals(aPropertiesSetAtStart) &&
!FindMatchingKeyframe(aKeyframes, 0.0, aInheritedTimingFunction,
startKeyframeIndex)) {
Keyframe newKeyframe;
newKeyframe.mOffset.emplace(0.0);
newKeyframe.mTimingFunction = aInheritedTimingFunction;
aKeyframes.InsertElementAt(startKeyframeIndex, Move(newKeyframe));
}
// Find/create the keyframe to add end values to
size_t endKeyframeIndex = kNotSet;
if (!aAnimatedProperties.Equals(aPropertiesSetAtEnd)) {
if (!FindMatchingKeyframe(Reversed(aKeyframes), 1.0,
aInheritedTimingFunction, endKeyframeIndex)) {
Keyframe newKeyframe;
newKeyframe.mOffset.emplace(1.0);
newKeyframe.mTimingFunction = aInheritedTimingFunction;
aKeyframes.AppendElement(Move(newKeyframe));
endKeyframeIndex = aKeyframes.Length() - 1;
} else {
// endKeyframeIndex is currently a count from the end of the array
// so we need to reverse it.
endKeyframeIndex = aKeyframes.Length() - 1 - endKeyframeIndex;
}
}
if (startKeyframeIndex == kNotSet && endKeyframeIndex == kNotSet) {
return;
}
// Now that we have finished manipulating aKeyframes, it is safe to
// take pointers to its elements.
Keyframe* startKeyframe = startKeyframeIndex == kNotSet
? nullptr : &aKeyframes[startKeyframeIndex];
Keyframe* endKeyframe = endKeyframeIndex == kNotSet
? nullptr : &aKeyframes[endKeyframeIndex];
// Iterate through all properties and fill-in missing values
for (nsCSSProperty prop = nsCSSProperty(0);
prop < eCSSProperty_COUNT_no_shorthands;
prop = nsCSSProperty(prop + 1)) {
if (!aAnimatedProperties.HasProperty(prop)) {
continue;
}
if (startKeyframe && !aPropertiesSetAtStart.HasProperty(prop)) {
AppendProperty(aPresContext, prop, startKeyframe->mPropertyValues);
}
if (endKeyframe && !aPropertiesSetAtEnd.HasProperty(prop)) {
AppendProperty(aPresContext, prop, endKeyframe->mPropertyValues);
}
}
}
void
CSSAnimationBuilder::AppendProperty(
nsPresContext* aPresContext,
nsCSSProperty aProperty,
nsTArray<PropertyValuePair>& aPropertyValues)
{
PropertyValuePair propertyValue;
propertyValue.mProperty = aProperty;
propertyValue.mValue = GetComputedValue(aPresContext, aProperty);
aPropertyValues.AppendElement(Move(propertyValue));
}
nsCSSValue
CSSAnimationBuilder::GetComputedValue(nsPresContext* aPresContext,
nsCSSProperty aProperty)
{
nsCSSValue result;
StyleAnimationValue computedValue;
if (!mStyleWithoutAnimation) {
MOZ_ASSERT(aPresContext->StyleSet()->IsGecko(),
"ServoStyleSet should not use nsAnimationManager for "
"animations");
mStyleWithoutAnimation = aPresContext->StyleSet()->AsGecko()->
ResolveStyleWithoutAnimation(mTarget, mStyleContext,
eRestyle_AllHintsWithAnimations);
}
if (StyleAnimationValue::ExtractComputedValue(aProperty,
mStyleWithoutAnimation,
computedValue)) {
StyleAnimationValue::UncomputeValue(aProperty, Move(computedValue), result);
}
// If we hit this assertion, it probably means we are fetching a value from
// the computed style that we don't know how to represent as
// a StyleAnimationValue.
MOZ_ASSERT(result.GetUnit() != eCSSUnit_Null, "Got null computed value");
return result;
}
void
nsAnimationManager::BuildAnimations(nsStyleContext* aStyleContext,
dom::Element* aTarget,
CSSAnimationCollection* aCollection,
OwningCSSAnimationPtrArray& aAnimations)
{
MOZ_ASSERT(aAnimations.IsEmpty(), "expect empty array");
const nsStyleDisplay *disp = aStyleContext->StyleDisplay();
CSSAnimationBuilder builder(aStyleContext, aTarget, aCollection);
for (size_t animIdx = disp->mAnimationNameCount; animIdx-- != 0;) {
const StyleAnimation& src = disp->mAnimations[animIdx];
// CSS Animations whose animation-name does not match a @keyframes rule do
// not generate animation events. This includes when the animation-name is
// "none" which is represented by an empty name in the StyleAnimation.
// Since such animations neither affect style nor dispatch events, we do
// not generate a corresponding CSSAnimation for them.
MOZ_ASSERT(mPresContext->StyleSet()->IsGecko(),
"ServoStyleSet should not use nsAnimationManager for "
"animations");
nsCSSKeyframesRule* rule =
src.GetName().IsEmpty()
? nullptr
: mPresContext->StyleSet()->AsGecko()->KeyframesRuleForName(src.GetName());
if (!rule) {
continue;
}
RefPtr<CSSAnimation> dest = builder.Build(mPresContext, src, rule);
dest->SetAnimationIndex(static_cast<uint64_t>(animIdx));
aAnimations.AppendElement(dest);
}
}
Reference in New Issue View Git Blame Copy Permalink