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/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*-
* 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
#include "FrameAnimator.h"
#include <utility>
#include "LookupResult.h"
#include "RasterImage.h"
#include "imgIContainer.h"
#include "mozilla/CheckedInt.h"
#include "mozilla/ProfilerLabels.h"
#include "mozilla/StaticPrefs_image.h"
namespace mozilla {
using namespace gfx;
namespace image {
///////////////////////////////////////////////////////////////////////////////
// AnimationState implementation.
///////////////////////////////////////////////////////////////////////////////
const gfx::IntRect AnimationState::UpdateState(
RasterImage* aImage, const gfx::IntSize& aSize,
bool aAllowInvalidation /* = true */) {
LookupResult result = SurfaceCache::Lookup(
ImageKey(aImage),
RasterSurfaceKey(aSize, DefaultSurfaceFlags(), PlaybackType::eAnimated),
/* aMarkUsed = */ false);
return UpdateStateInternal(result, aSize, aAllowInvalidation);
}
const gfx::IntRect AnimationState::UpdateStateInternal(
LookupResult& aResult, const gfx::IntSize& aSize,
bool aAllowInvalidation /* = true */) {
// Update mDiscarded and mIsCurrentlyDecoded.
if (aResult.Type() == MatchType::NOT_FOUND) {
// no frames, we've either been discarded, or never been decoded before.
mDiscarded = mHasBeenDecoded;
mIsCurrentlyDecoded = false;
} else if (aResult.Type() == MatchType::PENDING) {
// no frames yet, but a decoder is or will be working on it.
mDiscarded = false;
mIsCurrentlyDecoded = false;
mHasRequestedDecode = true;
} else {
MOZ_ASSERT(aResult.Type() == MatchType::EXACT);
mDiscarded = false;
mHasRequestedDecode = true;
// If we can seek to the current animation frame we consider it decoded.
// Animated images are never fully decoded unless very short.
// Note that we use GetFrame instead of Seek here. The difference is that
// Seek eventually calls AnimationFrameBuffer::Get with aForDisplay == true,
// whereas GetFrame calls AnimationFrameBuffer::Get with aForDisplay ==
// false. The aForDisplay can change whether those functions succeed or not
// (only for the first frame). Since this is not for display we want to pass
// aForDisplay == false, but also for consistency with
// RequestRefresh/AdvanceFrame, because we want our state to be in sync with
// those functions. The user of Seek (GetCompositedFrame) doesn't need to be
// in sync with our state.
RefPtr<imgFrame> currentFrame =
bool(aResult.Surface())
? aResult.Surface().GetFrame(mCurrentAnimationFrameIndex)
: nullptr;
mIsCurrentlyDecoded = !!currentFrame;
}
gfx::IntRect ret;
if (aAllowInvalidation) {
// Update the value of mCompositedFrameInvalid.
if (mIsCurrentlyDecoded) {
// It is safe to clear mCompositedFrameInvalid safe to do for images that
// are fully decoded but aren't finished animating because before we paint
// the refresh driver will call into us to advance to the correct frame,
// and that will succeed because we have all the frames.
if (mCompositedFrameInvalid) {
// Invalidate if we are marking the composited frame valid.
ret.SizeTo(aSize);
}
mCompositedFrameInvalid = false;
} else {
if (mHasRequestedDecode) {
MOZ_ASSERT(StaticPrefs::image_mem_animated_discardable_AtStartup());
mCompositedFrameInvalid = true;
}
}
// Otherwise don't change the value of mCompositedFrameInvalid, it will be
// updated by RequestRefresh.
}
return ret;
}
void AnimationState::NotifyDecodeComplete() { mHasBeenDecoded = true; }
void AnimationState::ResetAnimation() { mCurrentAnimationFrameIndex = 0; }
void AnimationState::SetAnimationMode(uint16_t aAnimationMode) {
mAnimationMode = aAnimationMode;
}
void AnimationState::UpdateKnownFrameCount(uint32_t aFrameCount) {
if (aFrameCount <= mFrameCount) {
// Nothing to do. Since we can redecode animated images, we may see the same
// sequence of updates replayed again, so seeing a smaller frame count than
// what we already know about doesn't indicate an error.
return;
}
MOZ_ASSERT(!mHasBeenDecoded, "Adding new frames after decoding is finished?");
MOZ_ASSERT(aFrameCount <= mFrameCount + 1, "Skipped a frame?");
mFrameCount = aFrameCount;
}
Maybe<uint32_t> AnimationState::FrameCount() const {
return mHasBeenDecoded ? Some(mFrameCount) : Nothing();
}
void AnimationState::SetFirstFrameRefreshArea(const IntRect& aRefreshArea) {
mFirstFrameRefreshArea = aRefreshArea;
}
void AnimationState::InitAnimationFrameTimeIfNecessary() {
if (mCurrentAnimationFrameTime.IsNull()) {
mCurrentAnimationFrameTime = TimeStamp::Now();
}
}
void AnimationState::SetAnimationFrameTime(const TimeStamp& aTime) {
mCurrentAnimationFrameTime = aTime;
}
bool AnimationState::MaybeAdvanceAnimationFrameTime(const TimeStamp& aTime) {
if (!StaticPrefs::image_animated_resume_from_last_displayed() ||
mCurrentAnimationFrameTime >= aTime) {
return false;
}
// We are configured to stop an animation when it is out of view, and restart
// it from the same point when it comes back into view. The same applies if it
// was discarded while out of view.
mCurrentAnimationFrameTime = aTime;
return true;
}
uint32_t AnimationState::GetCurrentAnimationFrameIndex() const {
return mCurrentAnimationFrameIndex;
}
FrameTimeout AnimationState::LoopLength() const {
// If we don't know the loop length yet, we have to treat it as infinite.
if (!mLoopLength) {
return FrameTimeout::Forever();
}
MOZ_ASSERT(mHasBeenDecoded,
"We know the loop length but decoding isn't done?");
// If we're not looping, a single loop time has no meaning.
if (mAnimationMode != imgIContainer::kNormalAnimMode) {
return FrameTimeout::Forever();
}
return *mLoopLength;
}
///////////////////////////////////////////////////////////////////////////////
// FrameAnimator implementation.
///////////////////////////////////////////////////////////////////////////////
TimeStamp FrameAnimator::GetCurrentImgFrameEndTime(
AnimationState& aState, FrameTimeout aCurrentTimeout) const {
if (aCurrentTimeout == FrameTimeout::Forever()) {
// We need to return a sentinel value in this case, because our logic
// doesn't work correctly if we have an infinitely long timeout. We use one
// year in the future as the sentinel because it works with the loop in
// RequestRefresh() below.
// XXX(seth): It'd be preferable to make our logic work correctly with
// infinitely long timeouts.
return TimeStamp::NowLoRes() + TimeDuration::FromMilliseconds(31536000.0);
}
TimeDuration durationOfTimeout =
TimeDuration::FromMilliseconds(double(aCurrentTimeout.AsMilliseconds()));
return aState.mCurrentAnimationFrameTime + durationOfTimeout;
}
RefreshResult FrameAnimator::AdvanceFrame(AnimationState& aState,
DrawableSurface& aFrames,
RefPtr<imgFrame>& aCurrentFrame,
TimeStamp aTime) {
AUTO_PROFILER_LABEL("FrameAnimator::AdvanceFrame", GRAPHICS);
RefreshResult ret;
// Determine what the next frame is, taking into account looping.
uint32_t currentFrameIndex = aState.mCurrentAnimationFrameIndex;
uint32_t nextFrameIndex = currentFrameIndex + 1;
// Check if we're at the end of the loop. (FrameCount() returns Nothing() if
// we don't know the total count yet.)
if (aState.FrameCount() == Some(nextFrameIndex)) {
// If we are not looping forever, initialize the loop counter
if (aState.mLoopRemainingCount < 0 && aState.LoopCount() >= 0) {
aState.mLoopRemainingCount = aState.LoopCount();
}
// If animation mode is "loop once", or we're at end of loop counter,
// it's time to stop animating.
if (aState.mAnimationMode == imgIContainer::kLoopOnceAnimMode ||
aState.mLoopRemainingCount == 0) {
ret.mAnimationFinished = true;
}
nextFrameIndex = 0;
if (aState.mLoopRemainingCount > 0) {
aState.mLoopRemainingCount--;
}
// If we're done, exit early.
if (ret.mAnimationFinished) {
return ret;
}
}
if (nextFrameIndex >= aState.KnownFrameCount()) {
// We've already advanced to the last decoded frame, nothing more we can do.
// We're blocked by network/decoding from displaying the animation at the
// rate specified, so that means the frame we are displaying (the latest
// available) is the frame we want to be displaying at this time. So we
// update the current animation time. If we didn't update the current
// animation time then it could lag behind, which would indicate that we are
// behind in the animation and should try to catch up. When we are done
// decoding (and thus can loop around back to the start of the animation) we
// would then jump to a random point in the animation to try to catch up.
// But we were never behind in the animation.
aState.mCurrentAnimationFrameTime = aTime;
return ret;
}
// There can be frames in the surface cache with index >= KnownFrameCount()
// which GetRawFrame() can access because an async decoder has decoded them,
// but which AnimationState doesn't know about yet because we haven't received
// the appropriate notification on the main thread. Make sure we stay in sync
// with AnimationState.
MOZ_ASSERT(nextFrameIndex < aState.KnownFrameCount());
RefPtr<imgFrame> nextFrame = aFrames.GetFrame(nextFrameIndex);
// We should always check to see if we have the next frame even if we have
// previously finished decoding. If we needed to redecode (e.g. due to a draw
// failure) we would have discarded all the old frames and may not yet have
// the new ones. DrawableSurface::RawAccessRef promises to only return
// finished frames.
if (!nextFrame) {
// Uh oh, the frame we want to show is currently being decoded (partial).
// Similar to the above case, we could be blocked by network or decoding,
// and so we should advance our current time rather than risk jumping
// through the animation. We will wait until the next refresh driver tick
// and try again.
aState.mCurrentAnimationFrameTime = aTime;
return ret;
}
if (nextFrame->GetTimeout() == FrameTimeout::Forever()) {
ret.mAnimationFinished = true;
}
if (nextFrameIndex == 0) {
ret.mDirtyRect = aState.FirstFrameRefreshArea();
} else {
ret.mDirtyRect = nextFrame->GetDirtyRect();
}
aState.mCurrentAnimationFrameTime =
GetCurrentImgFrameEndTime(aState, aCurrentFrame->GetTimeout());
// If we can get closer to the current time by a multiple of the image's loop
// time, we should. We can only do this if we're done decoding; otherwise, we
// don't know the full loop length, and LoopLength() will have to return
// FrameTimeout::Forever(). We also skip this for images with a finite loop
// count if we have initialized mLoopRemainingCount (it only gets initialized
// after one full loop).
FrameTimeout loopTime = aState.LoopLength();
if (loopTime != FrameTimeout::Forever() &&
(aState.LoopCount() < 0 || aState.mLoopRemainingCount >= 0)) {
TimeDuration delay = aTime - aState.mCurrentAnimationFrameTime;
if (delay.ToMilliseconds() > loopTime.AsMilliseconds()) {
// Explicitly use integer division to get the floor of the number of
// loops.
uint64_t loops = static_cast<uint64_t>(delay.ToMilliseconds()) /
loopTime.AsMilliseconds();
// If we have a finite loop count limit the number of loops we advance.
if (aState.mLoopRemainingCount >= 0) {
MOZ_ASSERT(aState.LoopCount() >= 0);
loops =
std::min(loops, CheckedUint64(aState.mLoopRemainingCount).value());
}
aState.mCurrentAnimationFrameTime +=
TimeDuration::FromMilliseconds(loops * loopTime.AsMilliseconds());
if (aState.mLoopRemainingCount >= 0) {
MOZ_ASSERT(loops <= CheckedUint64(aState.mLoopRemainingCount).value());
aState.mLoopRemainingCount -= CheckedInt32(loops).value();
}
}
}
// Set currentAnimationFrameIndex at the last possible moment
aState.mCurrentAnimationFrameIndex = nextFrameIndex;
aCurrentFrame = std::move(nextFrame);
aFrames.Advance(nextFrameIndex);
// If we're here, we successfully advanced the frame.
ret.mFrameAdvanced = true;
return ret;
}
void FrameAnimator::ResetAnimation(AnimationState& aState) {
aState.ResetAnimation();
// Our surface provider is synchronized to our state, so we need to reset its
// state as well, if we still have one.
SurfaceCache::ResetAnimation(
ImageKey(mImage),
RasterSurfaceKey(mSize, DefaultSurfaceFlags(), PlaybackType::eAnimated));
// Calling Reset on the surface of the animation can cause discarding surface
// providers to throw out all their frames so refresh our state.
OrientedIntRect rect =
OrientedIntRect::FromUnknownRect(aState.UpdateState(mImage, mSize));
if (!rect.IsEmpty()) {
nsCOMPtr<nsIEventTarget> eventTarget = do_GetMainThread();
RefPtr<RasterImage> image = mImage;
nsCOMPtr<nsIRunnable> ev = NS_NewRunnableFunction(
"FrameAnimator::ResetAnimation",
[=]() -> void { image->NotifyProgress(NoProgress, rect); });
eventTarget->Dispatch(ev.forget(), NS_DISPATCH_NORMAL);
}
}
RefreshResult FrameAnimator::RequestRefresh(AnimationState& aState,
const TimeStamp& aTime) {
// By default, an empty RefreshResult.
RefreshResult ret;
if (aState.IsDiscarded()) {
aState.MaybeAdvanceAnimationFrameTime(aTime);
return ret;
}
// Get the animation frames once now, and pass them down to callees because
// the surface could be discarded at anytime on a different thread. This is
// must easier to reason about then trying to write code that is safe to
// having the surface disappear at anytime.
LookupResult result = SurfaceCache::Lookup(
ImageKey(mImage),
RasterSurfaceKey(mSize, DefaultSurfaceFlags(), PlaybackType::eAnimated),
/* aMarkUsed = */ true);
ret.mDirtyRect = aState.UpdateStateInternal(result, mSize);
if (aState.IsDiscarded() || !result) {
aState.MaybeAdvanceAnimationFrameTime(aTime);
return ret;
}
RefPtr<imgFrame> currentFrame =
result.Surface().GetFrame(aState.mCurrentAnimationFrameIndex);
// only advance the frame if the current time is greater than or
// equal to the current frame's end time.
if (!currentFrame) {
MOZ_ASSERT(StaticPrefs::image_mem_animated_discardable_AtStartup());
MOZ_ASSERT(aState.GetHasRequestedDecode() &&
!aState.GetIsCurrentlyDecoded());
MOZ_ASSERT(aState.mCompositedFrameInvalid);
// Nothing we can do but wait for our previous current frame to be decoded
// again so we can determine what to do next.
aState.MaybeAdvanceAnimationFrameTime(aTime);
return ret;
}
TimeStamp currentFrameEndTime =
GetCurrentImgFrameEndTime(aState, currentFrame->GetTimeout());
// If nothing has accessed the composited frame since the last time we
// advanced, then there is no point in continuing to advance the animation.
// This has the effect of freezing the animation while not in view.
if (!result.Surface().MayAdvance() &&
aState.MaybeAdvanceAnimationFrameTime(aTime)) {
return ret;
}
while (currentFrameEndTime <= aTime) {
TimeStamp oldFrameEndTime = currentFrameEndTime;
RefreshResult frameRes =
AdvanceFrame(aState, result.Surface(), currentFrame, aTime);
// Accumulate our result for returning to callers.
ret.Accumulate(frameRes);
// currentFrame was updated by AdvanceFrame so it is still current.
currentFrameEndTime =
GetCurrentImgFrameEndTime(aState, currentFrame->GetTimeout());
// If we didn't advance a frame, and our frame end time didn't change,
// then we need to break out of this loop & wait for the frame(s)
// to finish downloading.
if (!frameRes.mFrameAdvanced && currentFrameEndTime == oldFrameEndTime) {
break;
}
}
// We should only mark the composited frame as valid and reset the dirty rect
// if we advanced (meaning the next frame was actually produced somehow), the
// composited frame was previously invalid (so we may need to repaint
// everything) and either the frame index is valid (to know we were doing
// blending on the main thread, instead of on the decoder threads in advance),
// or the current frame is a full frame (blends off the main thread).
//
// If for some reason we forget to reset aState.mCompositedFrameInvalid, then
// GetCompositedFrame will fail, even if we have all the data available for
// display.
if (currentFrameEndTime > aTime && aState.mCompositedFrameInvalid) {
aState.mCompositedFrameInvalid = false;
ret.mDirtyRect = IntRect(IntPoint(0, 0), mSize);
}
MOZ_ASSERT(!aState.mIsCurrentlyDecoded || !aState.mCompositedFrameInvalid);
return ret;
}
LookupResult FrameAnimator::GetCompositedFrame(AnimationState& aState,
bool aMarkUsed) {
LookupResult result = SurfaceCache::Lookup(
ImageKey(mImage),
RasterSurfaceKey(mSize, DefaultSurfaceFlags(), PlaybackType::eAnimated),
aMarkUsed);
if (result) {
// If we are getting the frame directly (e.g. through tests or canvas), we
// need to ensure the animation is marked to allow advancing to the next
// frame.
result.Surface().MarkMayAdvance();
}
if (aState.mCompositedFrameInvalid) {
MOZ_ASSERT(StaticPrefs::image_mem_animated_discardable_AtStartup());
MOZ_ASSERT(aState.GetHasRequestedDecode());
MOZ_ASSERT(!aState.GetIsCurrentlyDecoded());
if (result.Type() == MatchType::EXACT) {
// If our composited frame is marked as invalid but our frames are in the
// surface cache we might just have not updated our internal state yet.
// This can happen if the image is not in a document so that
// RequestRefresh is not getting called to advance the frame.
// RequestRefresh would result in our composited frame getting marked as
// valid either at the end of RequestRefresh when we are able to advance
// to the current time or if advancing frames eventually causes us to
// decode all of the frames of the image resulting in DecodeComplete
// getting called which calls UpdateState. The reason we care about this
// is that img.decode promises won't resolve until GetCompositedFrame
// returns a frame.
OrientedIntRect rect = OrientedIntRect::FromUnknownRect(
aState.UpdateStateInternal(result, mSize));
if (!rect.IsEmpty()) {
nsCOMPtr<nsIEventTarget> eventTarget = do_GetMainThread();
RefPtr<RasterImage> image = mImage;
nsCOMPtr<nsIRunnable> ev = NS_NewRunnableFunction(
"FrameAnimator::GetCompositedFrame",
[=]() -> void { image->NotifyProgress(NoProgress, rect); });
eventTarget->Dispatch(ev.forget(), NS_DISPATCH_NORMAL);
}
}
// If it's still invalid we have to return.
if (aState.mCompositedFrameInvalid) {
if (result.Type() == MatchType::NOT_FOUND) {
return result;
}
return LookupResult(MatchType::PENDING);
}
}
// Otherwise return the raw frame. DoBlend is required to ensure that we only
// hit this case if the frame is not paletted and doesn't require compositing.
if (!result) {
return result;
}
// Seek to the appropriate frame. If seeking fails, it means that we couldn't
// get the frame we're looking for; treat this as if the lookup failed.
if (NS_FAILED(result.Surface().Seek(aState.mCurrentAnimationFrameIndex))) {
if (result.Type() == MatchType::NOT_FOUND) {
return result;
}
return LookupResult(MatchType::PENDING);
}
return result;
}
} // namespace image
} // namespace mozilla