gecko-dev/layout/base/ActiveLayerTracker.cpp
Jamie Nicol 1c46abe6c4 Bug 1247336 - De-dupe changes in ActiveLayerTracker before treating property as animated. r=roc
In ActiveLayerTracker check if the value of a property has actually
changed, rather than being set to its existing value, before treating
the property as animated. This will help avoid over-layerization of some
frames.
2016-02-12 14:38:50 +00:00

546 lines
18 KiB
C++

/* 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 "ActiveLayerTracker.h"
#include "mozilla/ArrayUtils.h"
#include "mozilla/dom/KeyframeEffect.h"
#include "mozilla/gfx/Matrix.h"
#include "mozilla/EffectSet.h"
#include "mozilla/PodOperations.h"
#include "gfx2DGlue.h"
#include "nsExpirationTracker.h"
#include "nsContainerFrame.h"
#include "nsIContent.h"
#include "nsRefreshDriver.h"
#include "nsPIDOMWindow.h"
#include "nsIDocument.h"
#include "nsAnimationManager.h"
#include "nsStyleTransformMatrix.h"
#include "nsTransitionManager.h"
#include "nsDisplayList.h"
#include "nsDOMCSSDeclaration.h"
namespace mozilla {
using namespace gfx;
/**
* This tracks the state of a frame that may need active layers due to
* ongoing content changes or style changes that indicate animation.
*
* When no changes of *any* kind are detected after 75-100ms we remove this
* object. Because we only track all kinds of activity with a single
* nsExpirationTracker, it's possible a frame might remain active somewhat
* spuriously if different kinds of changes kept happening, but that almost
* certainly doesn't matter.
*/
class LayerActivity {
public:
enum ActivityIndex {
ACTIVITY_OPACITY,
ACTIVITY_TRANSFORM,
ACTIVITY_LEFT,
ACTIVITY_TOP,
ACTIVITY_RIGHT,
ACTIVITY_BOTTOM,
ACTIVITY_MARGIN_LEFT,
ACTIVITY_MARGIN_TOP,
ACTIVITY_MARGIN_RIGHT,
ACTIVITY_MARGIN_BOTTOM,
ACTIVITY_BACKGROUND_POSITION,
ACTIVITY_SCALE,
// keep as last item
ACTIVITY_COUNT
};
explicit LayerActivity(nsIFrame* aFrame)
: mFrame(aFrame)
, mContent(nullptr)
, mContentActive(false)
{
PodArrayZero(mRestyleCounts);
}
~LayerActivity();
nsExpirationState* GetExpirationState() { return &mState; }
uint8_t& RestyleCountForProperty(nsCSSProperty aProperty)
{
return mRestyleCounts[GetActivityIndexForProperty(aProperty)];
}
static ActivityIndex GetActivityIndexForProperty(nsCSSProperty aProperty)
{
switch (aProperty) {
case eCSSProperty_opacity: return ACTIVITY_OPACITY;
case eCSSProperty_transform: return ACTIVITY_TRANSFORM;
case eCSSProperty_left: return ACTIVITY_LEFT;
case eCSSProperty_top: return ACTIVITY_TOP;
case eCSSProperty_right: return ACTIVITY_RIGHT;
case eCSSProperty_bottom: return ACTIVITY_BOTTOM;
case eCSSProperty_margin_left: return ACTIVITY_MARGIN_LEFT;
case eCSSProperty_margin_top: return ACTIVITY_MARGIN_TOP;
case eCSSProperty_margin_right: return ACTIVITY_MARGIN_RIGHT;
case eCSSProperty_margin_bottom: return ACTIVITY_MARGIN_BOTTOM;
case eCSSProperty_background_position: return ACTIVITY_BACKGROUND_POSITION;
default: MOZ_ASSERT(false); return ACTIVITY_OPACITY;
}
}
// While tracked, exactly one of mFrame or mContent is non-null, depending
// on whether this property is stored on a frame or on a content node.
// When this property is expired by the layer activity tracker, both mFrame
// and mContent are nulled-out and the property is deleted.
nsIFrame* mFrame;
nsIContent* mContent;
nsExpirationState mState;
// Previous scale due to the CSS transform property.
Maybe<gfxSize> mPreviousTransformScale;
// The scroll frame during for which we most recently received a call to
// NotifyAnimatedFromScrollHandler.
nsWeakFrame mAnimatingScrollHandlerFrame;
// The set of activities that were triggered during
// mAnimatingScrollHandlerFrame's scroll event handler.
EnumSet<ActivityIndex> mScrollHandlerInducedActivity;
// Number of restyle operations detected
uint8_t mRestyleCounts[ACTIVITY_COUNT];
bool mContentActive;
};
class LayerActivityTracker final : public nsExpirationTracker<LayerActivity,4> {
public:
// 75-100ms is a good timeout period. We use 4 generations of 25ms each.
enum { GENERATION_MS = 100 };
LayerActivityTracker()
: nsExpirationTracker<LayerActivity,4>(GENERATION_MS,
"LayerActivityTracker")
, mDestroying(false)
{}
~LayerActivityTracker() {
mDestroying = true;
AgeAllGenerations();
}
virtual void NotifyExpired(LayerActivity* aObject);
public:
nsWeakFrame mCurrentScrollHandlerFrame;
private:
bool mDestroying;
};
static LayerActivityTracker* gLayerActivityTracker = nullptr;
LayerActivity::~LayerActivity()
{
if (mFrame || mContent) {
NS_ASSERTION(gLayerActivityTracker, "Should still have a tracker");
gLayerActivityTracker->RemoveObject(this);
}
}
// Frames with this property have NS_FRAME_HAS_LAYER_ACTIVITY_PROPERTY set
NS_DECLARE_FRAME_PROPERTY_DELETABLE(LayerActivityProperty, LayerActivity)
void
LayerActivityTracker::NotifyExpired(LayerActivity* aObject)
{
if (!mDestroying && aObject->mAnimatingScrollHandlerFrame.IsAlive()) {
// Reset the restyle counts, but let the layer activity survive.
PodArrayZero(aObject->mRestyleCounts);
MarkUsed(aObject);
return;
}
RemoveObject(aObject);
nsIFrame* f = aObject->mFrame;
nsIContent* c = aObject->mContent;
aObject->mFrame = nullptr;
aObject->mContent = nullptr;
MOZ_ASSERT((f == nullptr) != (c == nullptr),
"A LayerActivity object should always have a reference to either its frame or its content");
if (f) {
// The pres context might have been detached during the delay -
// that's fine, just skip the paint.
if (f->PresContext()->GetContainerWeak()) {
f->SchedulePaint();
}
f->RemoveStateBits(NS_FRAME_HAS_LAYER_ACTIVITY_PROPERTY);
f->Properties().Delete(LayerActivityProperty());
} else {
c->DeleteProperty(nsGkAtoms::LayerActivity);
}
}
static LayerActivity*
GetLayerActivity(nsIFrame* aFrame)
{
if (!aFrame->HasAnyStateBits(NS_FRAME_HAS_LAYER_ACTIVITY_PROPERTY)) {
return nullptr;
}
FrameProperties properties = aFrame->Properties();
return properties.Get(LayerActivityProperty());
}
static LayerActivity*
GetLayerActivityForUpdate(nsIFrame* aFrame)
{
FrameProperties properties = aFrame->Properties();
LayerActivity* layerActivity = properties.Get(LayerActivityProperty());
if (layerActivity) {
gLayerActivityTracker->MarkUsed(layerActivity);
} else {
if (!gLayerActivityTracker) {
gLayerActivityTracker = new LayerActivityTracker();
}
layerActivity = new LayerActivity(aFrame);
gLayerActivityTracker->AddObject(layerActivity);
aFrame->AddStateBits(NS_FRAME_HAS_LAYER_ACTIVITY_PROPERTY);
properties.Set(LayerActivityProperty(), layerActivity);
}
return layerActivity;
}
static void
IncrementMutationCount(uint8_t* aCount)
{
*aCount = uint8_t(std::min(0xFF, *aCount + 1));
}
/* static */ void
ActiveLayerTracker::TransferActivityToContent(nsIFrame* aFrame, nsIContent* aContent)
{
if (!aFrame->HasAnyStateBits(NS_FRAME_HAS_LAYER_ACTIVITY_PROPERTY)) {
return;
}
FrameProperties properties = aFrame->Properties();
LayerActivity* layerActivity = properties.Remove(LayerActivityProperty());
aFrame->RemoveStateBits(NS_FRAME_HAS_LAYER_ACTIVITY_PROPERTY);
if (!layerActivity) {
return;
}
layerActivity->mFrame = nullptr;
layerActivity->mContent = aContent;
aContent->SetProperty(nsGkAtoms::LayerActivity, layerActivity,
nsINode::DeleteProperty<LayerActivity>, true);
}
/* static */ void
ActiveLayerTracker::TransferActivityToFrame(nsIContent* aContent, nsIFrame* aFrame)
{
LayerActivity* layerActivity = static_cast<LayerActivity*>(
aContent->UnsetProperty(nsGkAtoms::LayerActivity));
if (!layerActivity) {
return;
}
layerActivity->mContent = nullptr;
layerActivity->mFrame = aFrame;
aFrame->AddStateBits(NS_FRAME_HAS_LAYER_ACTIVITY_PROPERTY);
aFrame->Properties().Set(LayerActivityProperty(), layerActivity);
}
static void
IncrementScaleRestyleCountIfNeeded(nsIFrame* aFrame, LayerActivity* aActivity)
{
const nsStyleDisplay* display = aFrame->StyleDisplay();
if (!display->mSpecifiedTransform) {
// The transform was removed.
aActivity->mPreviousTransformScale = Nothing();
IncrementMutationCount(&aActivity->mRestyleCounts[LayerActivity::ACTIVITY_SCALE]);
return;
}
// Compute the new scale due to the CSS transform property.
nsPresContext* presContext = aFrame->PresContext();
RuleNodeCacheConditions dummy;
bool dummyBool;
nsStyleTransformMatrix::TransformReferenceBox refBox(aFrame);
Matrix4x4 transform =
nsStyleTransformMatrix::ReadTransforms(display->mSpecifiedTransform->mHead,
aFrame->StyleContext(),
presContext,
dummy, refBox,
presContext->AppUnitsPerCSSPixel(),
&dummyBool);
Matrix transform2D;
if (!transform.Is2D(&transform2D)) {
// We don't attempt to handle 3D transforms; just assume the scale changed.
aActivity->mPreviousTransformScale = Nothing();
IncrementMutationCount(&aActivity->mRestyleCounts[LayerActivity::ACTIVITY_SCALE]);
return;
}
gfxSize scale = ThebesMatrix(transform2D).ScaleFactors(true);
if (aActivity->mPreviousTransformScale == Some(scale)) {
return; // Nothing changed.
}
aActivity->mPreviousTransformScale = Some(scale);
IncrementMutationCount(&aActivity->mRestyleCounts[LayerActivity::ACTIVITY_SCALE]);
}
/* static */ void
ActiveLayerTracker::NotifyRestyle(nsIFrame* aFrame, nsCSSProperty aProperty)
{
LayerActivity* layerActivity = GetLayerActivityForUpdate(aFrame);
uint8_t& mutationCount = layerActivity->RestyleCountForProperty(aProperty);
IncrementMutationCount(&mutationCount);
if (aProperty == eCSSProperty_transform) {
IncrementScaleRestyleCountIfNeeded(aFrame, layerActivity);
}
}
/* static */ void
ActiveLayerTracker::NotifyOffsetRestyle(nsIFrame* aFrame)
{
LayerActivity* layerActivity = GetLayerActivityForUpdate(aFrame);
IncrementMutationCount(&layerActivity->mRestyleCounts[LayerActivity::ACTIVITY_LEFT]);
IncrementMutationCount(&layerActivity->mRestyleCounts[LayerActivity::ACTIVITY_TOP]);
IncrementMutationCount(&layerActivity->mRestyleCounts[LayerActivity::ACTIVITY_RIGHT]);
IncrementMutationCount(&layerActivity->mRestyleCounts[LayerActivity::ACTIVITY_BOTTOM]);
}
/* static */ void
ActiveLayerTracker::NotifyAnimated(nsIFrame* aFrame,
nsCSSProperty aProperty,
const nsAString& aNewValue,
nsDOMCSSDeclaration* aDOMCSSDecl)
{
LayerActivity* layerActivity = GetLayerActivityForUpdate(aFrame);
uint8_t& mutationCount = layerActivity->RestyleCountForProperty(aProperty);
if (mutationCount != 0xFF) {
nsAutoString oldValue;
aDOMCSSDecl->GetPropertyValue(aProperty, oldValue);
if (aNewValue != oldValue) {
// We know this is animated, so just hack the mutation count.
mutationCount = 0xFF;
}
}
}
/* static */ void
ActiveLayerTracker::NotifyAnimatedFromScrollHandler(nsIFrame* aFrame, nsCSSProperty aProperty,
nsIFrame* aScrollFrame)
{
if (aFrame->PresContext() != aScrollFrame->PresContext()) {
// Don't allow cross-document dependencies.
return;
}
LayerActivity* layerActivity = GetLayerActivityForUpdate(aFrame);
LayerActivity::ActivityIndex activityIndex = LayerActivity::GetActivityIndexForProperty(aProperty);
if (layerActivity->mAnimatingScrollHandlerFrame.GetFrame() != aScrollFrame) {
// Discard any activity of a different scroll frame. We only track the
// most recent scroll handler induced activity.
layerActivity->mScrollHandlerInducedActivity.clear();
layerActivity->mAnimatingScrollHandlerFrame = aScrollFrame;
}
layerActivity->mScrollHandlerInducedActivity += activityIndex;
}
static bool
IsPresContextInScriptAnimationCallback(nsPresContext* aPresContext)
{
if (aPresContext->RefreshDriver()->IsInRefresh()) {
return true;
}
// Treat timeouts/setintervals as scripted animation callbacks for our
// purposes.
nsPIDOMWindowInner* win = aPresContext->Document()->GetInnerWindow();
return win && win->IsRunningTimeout();
}
/* static */ void
ActiveLayerTracker::NotifyInlineStyleRuleModified(nsIFrame* aFrame,
nsCSSProperty aProperty,
const nsAString& aNewValue,
nsDOMCSSDeclaration* aDOMCSSDecl)
{
if (IsPresContextInScriptAnimationCallback(aFrame->PresContext())) {
NotifyAnimated(aFrame, aProperty, aNewValue, aDOMCSSDecl);
}
if (gLayerActivityTracker &&
gLayerActivityTracker->mCurrentScrollHandlerFrame.IsAlive()) {
NotifyAnimatedFromScrollHandler(aFrame, aProperty,
gLayerActivityTracker->mCurrentScrollHandlerFrame.GetFrame());
}
}
/* static */ bool
ActiveLayerTracker::IsStyleMaybeAnimated(nsIFrame* aFrame, nsCSSProperty aProperty)
{
return IsStyleAnimated(nullptr, aFrame, aProperty);
}
static bool
CheckScrollInducedActivity(LayerActivity* aLayerActivity,
LayerActivity::ActivityIndex aActivityIndex,
nsDisplayListBuilder* aBuilder)
{
if (!aLayerActivity->mScrollHandlerInducedActivity.contains(aActivityIndex) ||
!aLayerActivity->mAnimatingScrollHandlerFrame.IsAlive()) {
return false;
}
nsIScrollableFrame* scrollFrame =
do_QueryFrame(aLayerActivity->mAnimatingScrollHandlerFrame.GetFrame());
if (scrollFrame && (!aBuilder || scrollFrame->IsScrollingActive(aBuilder))) {
return true;
}
// The scroll frame has been destroyed or has become inactive. Clear it from
// the layer activity so that it can expire.
aLayerActivity->mAnimatingScrollHandlerFrame = nullptr;
aLayerActivity->mScrollHandlerInducedActivity.clear();
return false;
}
/* static */ bool
ActiveLayerTracker::IsStyleAnimated(nsDisplayListBuilder* aBuilder,
nsIFrame* aFrame, nsCSSProperty aProperty)
{
// TODO: Add some abuse restrictions
if ((aFrame->StyleDisplay()->mWillChangeBitField & NS_STYLE_WILL_CHANGE_TRANSFORM) &&
aProperty == eCSSProperty_transform &&
(!aBuilder || aBuilder->IsInWillChangeBudget(aFrame, aFrame->GetSize()))) {
return true;
}
if ((aFrame->StyleDisplay()->mWillChangeBitField & NS_STYLE_WILL_CHANGE_OPACITY) &&
aProperty == eCSSProperty_opacity &&
(!aBuilder || aBuilder->IsInWillChangeBudget(aFrame, aFrame->GetSize()))) {
return true;
}
LayerActivity* layerActivity = GetLayerActivity(aFrame);
if (layerActivity) {
LayerActivity::ActivityIndex activityIndex = LayerActivity::GetActivityIndexForProperty(aProperty);
if (layerActivity->mRestyleCounts[activityIndex] >= 2) {
return true;
}
if (CheckScrollInducedActivity(layerActivity, activityIndex, aBuilder)) {
return true;
}
}
if (aProperty == eCSSProperty_transform && aFrame->Combines3DTransformWithAncestors()) {
return IsStyleAnimated(aBuilder, aFrame->GetParent(), aProperty);
}
return nsLayoutUtils::HasCurrentAnimationsForProperties(aFrame, &aProperty, 1);
}
/* static */ bool
ActiveLayerTracker::IsOffsetOrMarginStyleAnimated(nsIFrame* aFrame)
{
LayerActivity* layerActivity = GetLayerActivity(aFrame);
if (layerActivity) {
if (layerActivity->mRestyleCounts[LayerActivity::ACTIVITY_LEFT] >= 2 ||
layerActivity->mRestyleCounts[LayerActivity::ACTIVITY_TOP] >= 2 ||
layerActivity->mRestyleCounts[LayerActivity::ACTIVITY_RIGHT] >= 2 ||
layerActivity->mRestyleCounts[LayerActivity::ACTIVITY_BOTTOM] >= 2 ||
layerActivity->mRestyleCounts[LayerActivity::ACTIVITY_MARGIN_LEFT] >= 2 ||
layerActivity->mRestyleCounts[LayerActivity::ACTIVITY_MARGIN_TOP] >= 2 ||
layerActivity->mRestyleCounts[LayerActivity::ACTIVITY_MARGIN_RIGHT] >= 2 ||
layerActivity->mRestyleCounts[LayerActivity::ACTIVITY_MARGIN_BOTTOM] >= 2) {
return true;
}
}
// We should also check for running CSS animations of these properties once
// bug 1009693 is fixed. Until that happens, layerization isn't useful for
// animations of these properties because we'll invalidate the layer contents
// on every change anyway.
// See bug 1151346 for a patch that adds a check for CSS animations.
return false;
}
// A helper function for IsScaleSubjectToAnimation which returns true if the
// given EffectSet contains a current effect that animates scale.
static bool
ContainsAnimatedScale(EffectSet& aEffects, nsIFrame* aFrame)
{
for (dom::KeyframeEffectReadOnly* effect : aEffects) {
if (!effect->IsCurrent()) {
continue;
}
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;
}
/* static */ bool
ActiveLayerTracker::IsScaleSubjectToAnimation(nsIFrame* aFrame)
{
// Check whether JavaScript is animating this frame's scale.
LayerActivity* layerActivity = GetLayerActivity(aFrame);
if (layerActivity && layerActivity->mRestyleCounts[LayerActivity::ACTIVITY_SCALE] >= 2) {
return true;
}
// Check if any animations, transitions, etc. associated with this frame may
// animate its scale.
EffectSet* effects = EffectSet::GetEffectSet(aFrame);
if (effects && ContainsAnimatedScale(*effects, aFrame)) {
return true;
}
return false;
}
/* static */ void
ActiveLayerTracker::NotifyContentChange(nsIFrame* aFrame)
{
LayerActivity* layerActivity = GetLayerActivityForUpdate(aFrame);
layerActivity->mContentActive = true;
}
/* static */ bool
ActiveLayerTracker::IsContentActive(nsIFrame* aFrame)
{
LayerActivity* layerActivity = GetLayerActivity(aFrame);
return layerActivity && layerActivity->mContentActive;
}
/* static */ void
ActiveLayerTracker::SetCurrentScrollHandlerFrame(nsIFrame* aFrame)
{
if (!gLayerActivityTracker) {
gLayerActivityTracker = new LayerActivityTracker();
}
gLayerActivityTracker->mCurrentScrollHandlerFrame = aFrame;
}
/* static */ void
ActiveLayerTracker::Shutdown()
{
delete gLayerActivityTracker;
gLayerActivityTracker = nullptr;
}
} // namespace mozilla