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/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=8 sts=2 et sw=2 tw=80: */
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
#include "AnimationHelper.h"
#include "base/process_util.h"
#include "gfx2DGlue.h" // for ThebesRect
#include "gfxLineSegment.h" // for gfxLineSegment
#include "gfxPoint.h" // for gfxPoint
#include "gfxQuad.h" // for gfxQuad
#include "gfxRect.h" // for gfxRect
#include "gfxUtils.h" // for gfxUtils::TransformToQuad
#include "mozilla/ServoStyleConsts.h" // for StyleComputedTimingFunction
#include "mozilla/dom/AnimationEffectBinding.h" // for dom::FillMode
#include "mozilla/dom/KeyframeEffectBinding.h" // for dom::IterationComposite
#include "mozilla/dom/KeyframeEffect.h" // for dom::KeyFrameEffectReadOnly
#include "mozilla/dom/Nullable.h" // for dom::Nullable
#include "mozilla/layers/APZSampler.h" // for APZSampler
#include "mozilla/layers/CompositorThread.h" // for CompositorThreadHolder
#include "mozilla/LayerAnimationInfo.h" // for GetCSSPropertiesFor()
#include "mozilla/MotionPathUtils.h" // for ResolveMotionPath()
#include "mozilla/ServoBindings.h" // for Servo_ComposeAnimationSegment, etc
#include "mozilla/StyleAnimationValue.h" // for StyleAnimationValue, etc
#include "nsDeviceContext.h" // for AppUnitsPerCSSPixel
#include "nsDisplayList.h" // for nsDisplayTransform, etc
namespace mozilla {
namespace layers {
static dom::Nullable<TimeDuration> CalculateElapsedTimeForScrollTimeline(
const Maybe<APZSampler::ScrollOffsetAndRange> aScrollMeta,
const ScrollTimelineOptions& aOptions, const StickyTimeDuration& aEndTime,
const TimeDuration& aStartTime, float aPlaybackRate) {
// We return Nothing If the associated APZ controller is not available
// (because it may be destroyed but this animation is still alive).
if (!aScrollMeta) {
// This may happen after we reload a page. There may be a race condition
// because the animation is still alive but the APZ is destroyed. In this
// case, this animation is invalid, so we return nullptr.
return nullptr;
}
const bool isHorizontal =
aOptions.axis() == layers::ScrollDirection::eHorizontal;
double range =
isHorizontal ? aScrollMeta->mRange.width : aScrollMeta->mRange.height;
MOZ_ASSERT(
range > 0,
"We don't expect to get a zero or negative range on the compositor");
// The offset may be negative if the writing mode is from right to left.
// Use std::abs() here to avoid getting a negative progress.
double position =
std::abs(isHorizontal ? aScrollMeta->mOffset.x : aScrollMeta->mOffset.y);
double progress = position / range;
// Just in case to avoid getting a progress more than 100%, for overscrolling.
progress = std::min(progress, 1.0);
auto timelineTime = TimeDuration(aEndTime.MultDouble(progress));
return dom::Animation::CurrentTimeFromTimelineTime(timelineTime, aStartTime,
aPlaybackRate);
}
static dom::Nullable<TimeDuration> CalculateElapsedTime(
const APZSampler* aAPZSampler, const LayersId& aLayersId,
const MutexAutoLock& aProofOfMapLock, const PropertyAnimation& aAnimation,
const TimeStamp aPreviousFrameTime, const TimeStamp aCurrentFrameTime,
const AnimatedValue* aPreviousValue) {
// -------------------------------------
// Case 1: scroll-timeline animations.
// -------------------------------------
if (aAnimation.mScrollTimelineOptions) {
MOZ_ASSERT(
aAPZSampler,
"We don't send scroll animations to the compositor if APZ is disabled");
return CalculateElapsedTimeForScrollTimeline(
aAPZSampler->GetCurrentScrollOffsetAndRange(
aLayersId, aAnimation.mScrollTimelineOptions.value().source(),
aProofOfMapLock),
aAnimation.mScrollTimelineOptions.value(), aAnimation.mTiming.EndTime(),
aAnimation.mStartTime.refOr(aAnimation.mHoldTime),
aAnimation.mPlaybackRate);
}
// -------------------------------------
// Case 2: document-timeline animations.
// -------------------------------------
MOZ_ASSERT(
(!aAnimation.mOriginTime.IsNull() && aAnimation.mStartTime.isSome()) ||
aAnimation.mIsNotPlaying,
"If we are playing, we should have an origin time and a start time");
// Determine if the animation was play-pending and used a ready time later
// than the previous frame time.
//
// To determine this, _all_ of the following conditions need to hold:
//
// * There was no previous animation value (i.e. this is the first frame for
// the animation since it was sent to the compositor), and
// * The animation is playing, and
// * There is a previous frame time, and
// * The ready time of the animation is ahead of the previous frame time.
//
bool hasFutureReadyTime = false;
if (!aPreviousValue && !aAnimation.mIsNotPlaying &&
!aPreviousFrameTime.IsNull()) {
// This is the inverse of the calculation performed in
// AnimationInfo::StartPendingAnimations to calculate the start time of
// play-pending animations.
// Note that we have to calculate (TimeStamp + TimeDuration) last to avoid
// underflow in the middle of the calulation.
const TimeStamp readyTime =
aAnimation.mOriginTime +
(aAnimation.mStartTime.ref() +
aAnimation.mHoldTime.MultDouble(1.0 / aAnimation.mPlaybackRate));
hasFutureReadyTime = !readyTime.IsNull() && readyTime > aPreviousFrameTime;
}
// Use the previous vsync time to make main thread animations and compositor
// more closely aligned.
//
// On the first frame where we have animations the previous timestamp will
// not be set so we simply use the current timestamp. As a result we will
// end up painting the first frame twice. That doesn't appear to be
// noticeable, however.
//
// Likewise, if the animation is play-pending, it may have a ready time that
// is *after* |aPreviousFrameTime| (but *before* |aCurrentFrameTime|).
// To avoid flicker we need to use |aCurrentFrameTime| to avoid temporarily
// jumping backwards into the range prior to when the animation starts.
const TimeStamp& timeStamp = aPreviousFrameTime.IsNull() || hasFutureReadyTime
? aCurrentFrameTime
: aPreviousFrameTime;
// If the animation is not currently playing, e.g. paused or
// finished, then use the hold time to stay at the same position.
TimeDuration elapsedDuration =
aAnimation.mIsNotPlaying || aAnimation.mStartTime.isNothing()
? aAnimation.mHoldTime
: (timeStamp - aAnimation.mOriginTime - aAnimation.mStartTime.ref())
.MultDouble(aAnimation.mPlaybackRate);
return elapsedDuration;
}
enum class CanSkipCompose {
IfPossible,
No,
};
static AnimationHelper::SampleResult SampleAnimationForProperty(
const APZSampler* aAPZSampler, const LayersId& aLayersId,
const MutexAutoLock& aProofOfMapLock, TimeStamp aPreviousFrameTime,
TimeStamp aCurrentFrameTime, const AnimatedValue* aPreviousValue,
CanSkipCompose aCanSkipCompose,
nsTArray<PropertyAnimation>& aPropertyAnimations,
RefPtr<RawServoAnimationValue>& aAnimationValue) {
MOZ_ASSERT(!aPropertyAnimations.IsEmpty(), "Should have animations");
bool hasInEffectAnimations = false;
#ifdef DEBUG
// In cases where this function returns a SampleResult::Skipped, we actually
// do populate aAnimationValue in debug mode, so that we can MOZ_ASSERT at the
// call site that the value that would have been computed matches the stored
// value that we end up using. This flag is used to ensure we populate
// aAnimationValue in this scenario.
bool shouldBeSkipped = false;
#endif
// Process in order, since later animations override earlier ones.
for (PropertyAnimation& animation : aPropertyAnimations) {
dom::Nullable<TimeDuration> elapsedDuration = CalculateElapsedTime(
aAPZSampler, aLayersId, aProofOfMapLock, animation, aPreviousFrameTime,
aCurrentFrameTime, aPreviousValue);
const auto progressTimelinePosition =
animation.mScrollTimelineOptions
? dom::Animation::AtProgressTimelineBoundary(
TimeDuration::FromMilliseconds(
PROGRESS_TIMELINE_DURATION_MILLISEC),
elapsedDuration, animation.mStartTime.refOr(TimeDuration()),
animation.mPlaybackRate)
: dom::Animation::ProgressTimelinePosition::NotBoundary;
ComputedTiming computedTiming = dom::AnimationEffect::GetComputedTimingAt(
elapsedDuration, animation.mTiming, animation.mPlaybackRate,
progressTimelinePosition);
// FIXME: Bug 1776077, for the scroll-linked animations, it's possible to
// let it go from the active phase to the before phase, and its progress
// becomes null. In this case, we shouldn't just skip this animation.
// Instead, we have to reset the sampled result to that without this
// animation.
if (computedTiming.mProgress.IsNull()) {
continue;
}
dom::IterationCompositeOperation iterCompositeOperation =
animation.mIterationComposite;
// Skip calculation if the progress hasn't changed since the last
// calculation.
// Note that we don't skip calculate this animation if there is another
// animation since the other animation might be 'accumulate' or 'add', or
// might have a missing keyframe (i.e. this animation value will be used in
// the missing keyframe).
// FIXME Bug 1455476: We should do this optimizations for the case where
// the layer has multiple animations and multiple properties.
if (aCanSkipCompose == CanSkipCompose::IfPossible &&
!dom::KeyframeEffect::HasComputedTimingChanged(
computedTiming, iterCompositeOperation,
animation.mProgressOnLastCompose,
animation.mCurrentIterationOnLastCompose)) {
#ifdef DEBUG
shouldBeSkipped = true;
#else
return AnimationHelper::SampleResult::Skipped;
#endif
}
uint32_t segmentIndex = 0;
size_t segmentSize = animation.mSegments.Length();
PropertyAnimation::SegmentData* segment = animation.mSegments.Elements();
while (segment->mEndPortion < computedTiming.mProgress.Value() &&
segmentIndex < segmentSize - 1) {
++segment;
++segmentIndex;
}
double positionInSegment =
(computedTiming.mProgress.Value() - segment->mStartPortion) /
(segment->mEndPortion - segment->mStartPortion);
double portion = StyleComputedTimingFunction::GetPortion(
segment->mFunction, positionInSegment, computedTiming.mBeforeFlag);
// Like above optimization, skip calculation if the target segment isn't
// changed and if the portion in the segment isn't changed.
// This optimization is needed for CSS animations/transitions with step
// timing functions (e.g. the throbber animation on tabs or frame based
// animations).
// FIXME Bug 1455476: Like the above optimization, we should apply this
// optimizations for multiple animation cases and multiple properties as
// well.
if (aCanSkipCompose == CanSkipCompose::IfPossible &&
animation.mSegmentIndexOnLastCompose == segmentIndex &&
!animation.mPortionInSegmentOnLastCompose.IsNull() &&
animation.mPortionInSegmentOnLastCompose.Value() == portion) {
#ifdef DEBUG
shouldBeSkipped = true;
#else
return AnimationHelper::SampleResult::Skipped;
#endif
}
AnimationPropertySegment animSegment;
animSegment.mFromKey = 0.0;
animSegment.mToKey = 1.0;
animSegment.mFromValue = AnimationValue(segment->mStartValue);
animSegment.mToValue = AnimationValue(segment->mEndValue);
animSegment.mFromComposite = segment->mStartComposite;
animSegment.mToComposite = segment->mEndComposite;
// interpolate the property
aAnimationValue =
Servo_ComposeAnimationSegment(
&animSegment, aAnimationValue,
animation.mSegments.LastElement().mEndValue, iterCompositeOperation,
portion, computedTiming.mCurrentIteration)
.Consume();
#ifdef DEBUG
if (shouldBeSkipped) {
return AnimationHelper::SampleResult::Skipped;
}
#endif
hasInEffectAnimations = true;
animation.mProgressOnLastCompose = computedTiming.mProgress;
animation.mCurrentIterationOnLastCompose = computedTiming.mCurrentIteration;
animation.mSegmentIndexOnLastCompose = segmentIndex;
animation.mPortionInSegmentOnLastCompose.SetValue(portion);
}
return hasInEffectAnimations ? AnimationHelper::SampleResult::Sampled
: AnimationHelper::SampleResult::None;
}
AnimationHelper::SampleResult AnimationHelper::SampleAnimationForEachNode(
const APZSampler* aAPZSampler, const LayersId& aLayersId,
const MutexAutoLock& aProofOfMapLock, TimeStamp aPreviousFrameTime,
TimeStamp aCurrentFrameTime, const AnimatedValue* aPreviousValue,
nsTArray<PropertyAnimationGroup>& aPropertyAnimationGroups,
nsTArray<RefPtr<RawServoAnimationValue>>& aAnimationValues /* out */) {
MOZ_ASSERT(!aPropertyAnimationGroups.IsEmpty(),
"Should be called with animation data");
MOZ_ASSERT(aAnimationValues.IsEmpty(),
"Should be called with empty aAnimationValues");
nsTArray<RefPtr<RawServoAnimationValue>> nonAnimatingValues;
for (PropertyAnimationGroup& group : aPropertyAnimationGroups) {
// Initialize animation value with base style.
RefPtr<RawServoAnimationValue> currValue = group.mBaseStyle;
CanSkipCompose canSkipCompose =
aPreviousValue && aPropertyAnimationGroups.Length() == 1 &&
group.mAnimations.Length() == 1
? CanSkipCompose::IfPossible
: CanSkipCompose::No;
MOZ_ASSERT(
!group.mAnimations.IsEmpty() ||
nsCSSPropertyIDSet::TransformLikeProperties().HasProperty(
group.mProperty),
"Only transform-like properties can have empty PropertyAnimation list");
// For properties which are not animating (i.e. their values are always the
// same), we store them in a different array, and then merge them into the
// final result (a.k.a. aAnimationValues) because we shouldn't take them
// into account for SampleResult. (In other words, these properties
// shouldn't affect the optimization.)
if (group.mAnimations.IsEmpty()) {
nonAnimatingValues.AppendElement(std::move(currValue));
continue;
}
SampleResult result = SampleAnimationForProperty(
aAPZSampler, aLayersId, aProofOfMapLock, aPreviousFrameTime,
aCurrentFrameTime, aPreviousValue, canSkipCompose, group.mAnimations,
currValue);
// FIXME: Bug 1455476: Do optimization for multiple properties. For now,
// the result is skipped only if the property count == 1.
if (result == SampleResult::Skipped) {
#ifdef DEBUG
aAnimationValues.AppendElement(std::move(currValue));
#endif
return SampleResult::Skipped;
}
if (result != SampleResult::Sampled) {
continue;
}
// Insert the interpolation result into the output array.
MOZ_ASSERT(currValue);
aAnimationValues.AppendElement(std::move(currValue));
}
SampleResult rv =
aAnimationValues.IsEmpty() ? SampleResult::None : SampleResult::Sampled;
if (rv == SampleResult::Sampled) {
aAnimationValues.AppendElements(std::move(nonAnimatingValues));
}
return rv;
}
static dom::FillMode GetAdjustedFillMode(const Animation& aAnimation) {
// Adjust fill mode so that if the main thread is delayed in clearing
// this animation we don't introduce flicker by jumping back to the old
// underlying value.
auto fillMode = static_cast<dom::FillMode>(aAnimation.fillMode());
float playbackRate = aAnimation.playbackRate();
switch (fillMode) {
case dom::FillMode::None:
if (playbackRate > 0) {
fillMode = dom::FillMode::Forwards;
} else if (playbackRate < 0) {
fillMode = dom::FillMode::Backwards;
}
break;
case dom::FillMode::Backwards:
if (playbackRate > 0) {
fillMode = dom::FillMode::Both;
}
break;
case dom::FillMode::Forwards:
if (playbackRate < 0) {
fillMode = dom::FillMode::Both;
}
break;
default:
break;
}
return fillMode;
}
#ifdef DEBUG
static bool HasTransformLikeAnimations(const AnimationArray& aAnimations) {
nsCSSPropertyIDSet transformSet =
nsCSSPropertyIDSet::TransformLikeProperties();
for (const Animation& animation : aAnimations) {
if (animation.isNotAnimating()) {
continue;
}
if (transformSet.HasProperty(animation.property())) {
return true;
}
}
return false;
}
#endif
AnimationStorageData AnimationHelper::ExtractAnimations(
const LayersId& aLayersId, const AnimationArray& aAnimations) {
AnimationStorageData storageData;
storageData.mLayersId = aLayersId;
nsCSSPropertyID prevID = eCSSProperty_UNKNOWN;
PropertyAnimationGroup* currData = nullptr;
DebugOnly<const layers::Animatable*> currBaseStyle = nullptr;
for (const Animation& animation : aAnimations) {
// Animations with same property are grouped together, so we can just
// check if the current property is the same as the previous one for
// knowing this is a new group.
if (prevID != animation.property()) {
// Got a different group, we should create a different array.
currData = storageData.mAnimation.AppendElement();
currData->mProperty = animation.property();
if (animation.transformData()) {
MOZ_ASSERT(!storageData.mTransformData,
"Only one entry has TransformData");
storageData.mTransformData = animation.transformData();
}
prevID = animation.property();
// Reset the debug pointer.
currBaseStyle = nullptr;
}
MOZ_ASSERT(currData);
if (animation.baseStyle().type() != Animatable::Tnull_t) {
MOZ_ASSERT(!currBaseStyle || *currBaseStyle == animation.baseStyle(),
"Should be the same base style");
currData->mBaseStyle = AnimationValue::FromAnimatable(
animation.property(), animation.baseStyle());
currBaseStyle = &animation.baseStyle();
}
// If this layers::Animation sets isNotAnimating to true, it only has
// base style and doesn't have any animation information, so we can skip
// the rest steps. (And so its PropertyAnimationGroup::mAnimation will be
// an empty array.)
if (animation.isNotAnimating()) {
MOZ_ASSERT(nsCSSPropertyIDSet::TransformLikeProperties().HasProperty(
animation.property()),
"Only transform-like properties could set this true");
if (animation.property() == eCSSProperty_offset_path) {
MOZ_ASSERT(currData->mBaseStyle,
"Fixed offset-path should have base style");
MOZ_ASSERT(HasTransformLikeAnimations(aAnimations));
AnimationValue value{currData->mBaseStyle};
const StyleOffsetPath& offsetPath = value.GetOffsetPathProperty();
if (offsetPath.IsPath()) {
MOZ_ASSERT(!storageData.mCachedMotionPath,
"Only one offset-path: path() is set");
RefPtr<gfx::PathBuilder> builder =
MotionPathUtils::GetCompositorPathBuilder();
storageData.mCachedMotionPath =
MotionPathUtils::BuildPath(offsetPath.AsPath(), builder);
}
}
continue;
}
PropertyAnimation* propertyAnimation =
currData->mAnimations.AppendElement();
propertyAnimation->mOriginTime = animation.originTime();
propertyAnimation->mStartTime = animation.startTime();
propertyAnimation->mHoldTime = animation.holdTime();
propertyAnimation->mPlaybackRate = animation.playbackRate();
propertyAnimation->mIterationComposite =
static_cast<dom::IterationCompositeOperation>(
animation.iterationComposite());
propertyAnimation->mIsNotPlaying = animation.isNotPlaying();
propertyAnimation->mTiming =
TimingParams{animation.duration(),
animation.delay(),
animation.endDelay(),
animation.iterations(),
animation.iterationStart(),
static_cast<dom::PlaybackDirection>(animation.direction()),
GetAdjustedFillMode(animation),
animation.easingFunction()};
propertyAnimation->mScrollTimelineOptions =
animation.scrollTimelineOptions();
nsTArray<PropertyAnimation::SegmentData>& segmentData =
propertyAnimation->mSegments;
for (const AnimationSegment& segment : animation.segments()) {
segmentData.AppendElement(PropertyAnimation::SegmentData{
AnimationValue::FromAnimatable(animation.property(),
segment.startState()),
AnimationValue::FromAnimatable(animation.property(),
segment.endState()),
segment.sampleFn(), segment.startPortion(), segment.endPortion(),
static_cast<dom::CompositeOperation>(segment.startComposite()),
static_cast<dom::CompositeOperation>(segment.endComposite())});
}
}
#ifdef DEBUG
// Sanity check that the grouped animation data is correct by looking at the
// property set.
if (!storageData.mAnimation.IsEmpty()) {
nsCSSPropertyIDSet seenProperties;
for (const auto& group : storageData.mAnimation) {
nsCSSPropertyID id = group.mProperty;
MOZ_ASSERT(!seenProperties.HasProperty(id), "Should be a new property");
seenProperties.AddProperty(id);
}
MOZ_ASSERT(
seenProperties.IsSubsetOf(LayerAnimationInfo::GetCSSPropertiesFor(
DisplayItemType::TYPE_TRANSFORM)) ||
seenProperties.IsSubsetOf(LayerAnimationInfo::GetCSSPropertiesFor(
DisplayItemType::TYPE_OPACITY)) ||
seenProperties.IsSubsetOf(LayerAnimationInfo::GetCSSPropertiesFor(
DisplayItemType::TYPE_BACKGROUND_COLOR)),
"The property set of output should be the subset of transform-like "
"properties, opacity, or background_color.");
if (seenProperties.IsSubsetOf(LayerAnimationInfo::GetCSSPropertiesFor(
DisplayItemType::TYPE_TRANSFORM))) {
MOZ_ASSERT(storageData.mTransformData, "Should have TransformData");
}
if (seenProperties.HasProperty(eCSSProperty_offset_path)) {
MOZ_ASSERT(storageData.mTransformData, "Should have TransformData");
MOZ_ASSERT(storageData.mTransformData->motionPathData(),
"Should have MotionPathData");
}
}
#endif
return storageData;
}
uint64_t AnimationHelper::GetNextCompositorAnimationsId() {
static uint32_t sNextId = 0;
++sNextId;
uint32_t procId = static_cast<uint32_t>(base::GetCurrentProcId());
uint64_t nextId = procId;
nextId = nextId << 32 | sNextId;
return nextId;
}
gfx::Matrix4x4 AnimationHelper::ServoAnimationValueToMatrix4x4(
const nsTArray<RefPtr<RawServoAnimationValue>>& aValues,
const TransformData& aTransformData, gfx::Path* aCachedMotionPath) {
using nsStyleTransformMatrix::TransformReferenceBox;
// This is a bit silly just to avoid the transform list copy from the
// animation transform list.
auto noneTranslate = StyleTranslate::None();
auto noneRotate = StyleRotate::None();
auto noneScale = StyleScale::None();
const StyleTransform noneTransform;
const StyleTranslate* translate = nullptr;
const StyleRotate* rotate = nullptr;
const StyleScale* scale = nullptr;
const StyleTransform* transform = nullptr;
const StyleOffsetPath* path = nullptr;
const StyleLengthPercentage* distance = nullptr;
const StyleOffsetRotate* offsetRotate = nullptr;
const StylePositionOrAuto* anchor = nullptr;
for (const auto& value : aValues) {
MOZ_ASSERT(value);
nsCSSPropertyID id = Servo_AnimationValue_GetPropertyId(value);
switch (id) {
case eCSSProperty_transform:
MOZ_ASSERT(!transform);
transform = Servo_AnimationValue_GetTransform(value);
break;
case eCSSProperty_translate:
MOZ_ASSERT(!translate);
translate = Servo_AnimationValue_GetTranslate(value);
break;
case eCSSProperty_rotate:
MOZ_ASSERT(!rotate);
rotate = Servo_AnimationValue_GetRotate(value);
break;
case eCSSProperty_scale:
MOZ_ASSERT(!scale);
scale = Servo_AnimationValue_GetScale(value);
break;
case eCSSProperty_offset_path:
MOZ_ASSERT(!path);
path = Servo_AnimationValue_GetOffsetPath(value);
break;
case eCSSProperty_offset_distance:
MOZ_ASSERT(!distance);
distance = Servo_AnimationValue_GetOffsetDistance(value);
break;
case eCSSProperty_offset_rotate:
MOZ_ASSERT(!offsetRotate);
offsetRotate = Servo_AnimationValue_GetOffsetRotate(value);
break;
case eCSSProperty_offset_anchor:
MOZ_ASSERT(!anchor);
anchor = Servo_AnimationValue_GetOffsetAnchor(value);
break;
default:
MOZ_ASSERT_UNREACHABLE("Unsupported transform-like property");
}
}
TransformReferenceBox refBox(nullptr, aTransformData.bounds());
Maybe<ResolvedMotionPathData> motion = MotionPathUtils::ResolveMotionPath(
path, distance, offsetRotate, anchor, aTransformData.motionPathData(),
refBox, aCachedMotionPath);
// We expect all our transform data to arrive in device pixels
gfx::Point3D transformOrigin = aTransformData.transformOrigin();
nsDisplayTransform::FrameTransformProperties props(
translate ? *translate : noneTranslate, rotate ? *rotate : noneRotate,
scale ? *scale : noneScale, transform ? *transform : noneTransform,
motion, transformOrigin);
return nsDisplayTransform::GetResultingTransformMatrix(
props, refBox, aTransformData.appUnitsPerDevPixel());
}
static uint8_t CollectOverflowedSideLines(const gfxQuad& aPrerenderedQuad,
SideBits aOverflowSides,
gfxLineSegment sideLines[4]) {
uint8_t count = 0;
if (aOverflowSides & SideBits::eTop) {
sideLines[count] = gfxLineSegment(aPrerenderedQuad.mPoints[0],
aPrerenderedQuad.mPoints[1]);
count++;
}
if (aOverflowSides & SideBits::eRight) {
sideLines[count] = gfxLineSegment(aPrerenderedQuad.mPoints[1],
aPrerenderedQuad.mPoints[2]);
count++;
}
if (aOverflowSides & SideBits::eBottom) {
sideLines[count] = gfxLineSegment(aPrerenderedQuad.mPoints[2],
aPrerenderedQuad.mPoints[3]);
count++;
}
if (aOverflowSides & SideBits::eLeft) {
sideLines[count] = gfxLineSegment(aPrerenderedQuad.mPoints[3],
aPrerenderedQuad.mPoints[0]);
count++;
}
return count;
}
enum RegionBits : uint8_t {
Inside = 0,
Left = (1 << 0),
Right = (1 << 1),
Bottom = (1 << 2),
Top = (1 << 3),
};
MOZ_MAKE_ENUM_CLASS_BITWISE_OPERATORS(RegionBits);
static RegionBits GetRegionBitsForPoint(double aX, double aY,
const gfxRect& aClip) {
RegionBits result = RegionBits::Inside;
if (aX < aClip.X()) {
result |= RegionBits::Left;
} else if (aX > aClip.XMost()) {
result |= RegionBits::Right;
}
if (aY < aClip.Y()) {
result |= RegionBits::Bottom;
} else if (aY > aClip.YMost()) {
result |= RegionBits::Top;
}
return result;
};
static bool LineSegmentIntersectsClip(double aX0, double aY0, double aX1,
double aY1, const gfxRect& aClip) {
RegionBits b0 = GetRegionBitsForPoint(aX0, aY0, aClip);
RegionBits b1 = GetRegionBitsForPoint(aX1, aY1, aClip);
while (true) {
if (!(b0 | b1)) {
// Completely inside.
return true;
}
if (b0 & b1) {
// Completely outside.
return false;
}
double x, y;
// Choose an outside point.
RegionBits outsidePointBits = b1 > b0 ? b1 : b0;
if (outsidePointBits & RegionBits::Top) {
x = aX0 + (aX1 - aX0) * (aClip.YMost() - aY0) / (aY1 - aY0);
y = aClip.YMost();
} else if (outsidePointBits & RegionBits::Bottom) {
x = aX0 + (aX1 - aX0) * (aClip.Y() - aY0) / (aY1 - aY0);
y = aClip.Y();
} else if (outsidePointBits & RegionBits::Right) {
y = aY0 + (aY1 - aY0) * (aClip.XMost() - aX0) / (aX1 - aX0);
x = aClip.XMost();
} else if (outsidePointBits & RegionBits::Left) {
y = aY0 + (aY1 - aY0) * (aClip.X() - aX0) / (aX1 - aX0);
x = aClip.X();
}
if (outsidePointBits == b0) {
aX0 = x;
aY0 = y;
b0 = GetRegionBitsForPoint(aX0, aY0, aClip);
} else {
aX1 = x;
aY1 = y;
b1 = GetRegionBitsForPoint(aX1, aY1, aClip);
}
}
MOZ_ASSERT_UNREACHABLE();
return false;
}
// static
bool AnimationHelper::ShouldBeJank(const LayoutDeviceRect& aPrerenderedRect,
SideBits aOverflowSides,
const gfx::Matrix4x4& aTransform,
const ParentLayerRect& aClipRect) {
if (aClipRect.IsEmpty()) {
return false;
}
gfxQuad prerenderedQuad = gfxUtils::TransformToQuad(
ThebesRect(aPrerenderedRect.ToUnknownRect()), aTransform);
gfxLineSegment sideLines[4];
uint8_t overflowSideCount =
CollectOverflowedSideLines(prerenderedQuad, aOverflowSides, sideLines);
gfxRect clipRect = ThebesRect(aClipRect.ToUnknownRect());
for (uint8_t j = 0; j < overflowSideCount; j++) {
if (LineSegmentIntersectsClip(sideLines[j].mStart.x, sideLines[j].mStart.y,
sideLines[j].mEnd.x, sideLines[j].mEnd.y,
clipRect)) {
return true;
}
}
// With step timing functions there are cases the transform jumps to a
// position where the partial pre-render area is totally outside of the clip
// rect without any intersection of the partial pre-render area and the clip
// rect happened in previous compositions but there remains visible area of
// the entire transformed area.
//
// So now all four points of the transformed partial pre-render rect are
// outside of the clip rect, if all these four points are in either side of
// the clip rect, we consider it's jank so that on the main-thread we will
// either a) rebuild the up-to-date display item if there remains visible area
// or b) no longer rebuild the display item if it's totally outside of the
// clip rect.
//
// Note that RegionBits::Left and Right are mutually exclusive,
// RegionBits::Top and Bottom are also mutually exclusive, so if there remains
// any bits, it means all four points are in the same side.
return GetRegionBitsForPoint(prerenderedQuad.mPoints[0].x,
prerenderedQuad.mPoints[0].y, clipRect) &
GetRegionBitsForPoint(prerenderedQuad.mPoints[1].x,
prerenderedQuad.mPoints[1].y, clipRect) &
GetRegionBitsForPoint(prerenderedQuad.mPoints[2].x,
prerenderedQuad.mPoints[2].y, clipRect) &
GetRegionBitsForPoint(prerenderedQuad.mPoints[3].x,
prerenderedQuad.mPoints[3].y, clipRect);
}
} // namespace layers
} // namespace mozilla