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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
#include "SMILTimeContainer.h"
#include "mozilla/AutoRestore.h"
#include "mozilla/CheckedInt.h"
#include "mozilla/SMILTimedElement.h"
#include "mozilla/SMILTimeValue.h"
#include <algorithm>
namespace mozilla {
SMILTimeContainer::SMILTimeContainer()
: mParent(nullptr),
mCurrentTime(0L),
mParentOffset(0L),
mPauseStart(0L),
mNeedsPauseSample(false),
mNeedsRewind(false),
mIsSeeking(false),
#ifdef DEBUG
mHoldingEntries(false),
#endif
mPauseState(PAUSE_BEGIN) {
}
SMILTimeContainer::~SMILTimeContainer() {
if (mParent) {
mParent->RemoveChild(*this);
}
}
SMILTimeValue SMILTimeContainer::ContainerToParentTime(
SMILTime aContainerTime) const {
// If we're paused, then future times are indefinite
if (IsPaused() && aContainerTime > mCurrentTime)
return SMILTimeValue::Indefinite();
return SMILTimeValue(aContainerTime + mParentOffset);
}
SMILTimeValue SMILTimeContainer::ParentToContainerTime(
SMILTime aParentTime) const {
// If we're paused, then any time after when we paused is indefinite
if (IsPaused() && aParentTime > mPauseStart)
return SMILTimeValue::Indefinite();
return SMILTimeValue(aParentTime - mParentOffset);
}
void SMILTimeContainer::Begin() {
Resume(PAUSE_BEGIN);
if (mPauseState) {
mNeedsPauseSample = true;
}
// This is a little bit complicated here. Ideally we'd just like to call
// Sample() and force an initial sample but this turns out to be a bad idea
// because this may mean that NeedsSample() no longer reports true and so when
// we come to the first real sample our parent will skip us over altogether.
// So we force the time to be updated and adopt the policy to never call
// Sample() ourselves but to always leave that to our parent or client.
UpdateCurrentTime();
}
void SMILTimeContainer::Pause(uint32_t aType) {
bool didStartPause = false;
if (!mPauseState && aType) {
mPauseStart = GetParentTime();
mNeedsPauseSample = true;
didStartPause = true;
}
mPauseState |= aType;
if (didStartPause) {
NotifyTimeChange();
}
}
void SMILTimeContainer::Resume(uint32_t aType) {
if (!mPauseState) return;
mPauseState &= ~aType;
if (!mPauseState) {
SMILTime extraOffset = GetParentTime() - mPauseStart;
mParentOffset += extraOffset;
NotifyTimeChange();
}
}
SMILTime SMILTimeContainer::GetCurrentTimeAsSMILTime() const {
// The following behaviour is consistent with:
// #getCurrentTime_setCurrentTime_undefined_before_document_timeline_begin
// which says that if GetCurrentTime is called before the document timeline
// has begun we should just return 0.
if (IsPausedByType(PAUSE_BEGIN)) return 0L;
return mCurrentTime;
}
void SMILTimeContainer::SetCurrentTime(SMILTime aSeekTo) {
// SVG 1.1 doesn't specify what to do for negative times so we adopt SVGT1.2's
// behaviour of clamping negative times to 0.
aSeekTo = std::max<SMILTime>(0, aSeekTo);
// The following behaviour is consistent with:
// #getCurrentTime_setCurrentTime_undefined_before_document_timeline_begin
// which says that if SetCurrentTime is called before the document timeline
// has begun we should still adjust the offset.
SMILTime parentTime = GetParentTime();
mParentOffset = parentTime - aSeekTo;
mIsSeeking = true;
if (IsPaused()) {
mNeedsPauseSample = true;
mPauseStart = parentTime;
}
if (aSeekTo < mCurrentTime) {
// Backwards seek
mNeedsRewind = true;
ClearMilestones();
}
// Force an update to the current time in case we get a call to GetCurrentTime
// before another call to Sample().
UpdateCurrentTime();
NotifyTimeChange();
}
SMILTime SMILTimeContainer::GetParentTime() const {
if (mParent) return mParent->GetCurrentTimeAsSMILTime();
return 0L;
}
void SMILTimeContainer::SyncPauseTime() {
if (IsPaused()) {
SMILTime parentTime = GetParentTime();
SMILTime extraOffset = parentTime - mPauseStart;
mParentOffset += extraOffset;
mPauseStart = parentTime;
}
}
void SMILTimeContainer::Sample() {
if (!NeedsSample()) return;
UpdateCurrentTime();
DoSample();
mNeedsPauseSample = false;
}
nsresult SMILTimeContainer::SetParent(SMILTimeContainer* aParent) {
if (mParent) {
mParent->RemoveChild(*this);
// When we're not attached to a parent time container, GetParentTime() will
// return 0. We need to adjust our pause state information to be relative to
// this new time base.
// Note that since "current time = parent time - parent offset" setting the
// parent offset and pause start as follows preserves our current time even
// while parent time = 0.
mParentOffset = -mCurrentTime;
mPauseStart = 0L;
}
mParent = aParent;
nsresult rv = NS_OK;
if (mParent) {
rv = mParent->AddChild(*this);
}
return rv;
}
void SMILTimeContainer::AddMilestone(
const SMILMilestone& aMilestone,
mozilla::dom::SVGAnimationElement& aElement) {
// We record the milestone time and store it along with the element but this
// time may change (e.g. if attributes are changed on the timed element in
// between samples). If this happens, then we may do an unecessary sample
// but that's pretty cheap.
MOZ_ASSERT(!mHoldingEntries);
mMilestoneEntries.Push(MilestoneEntry(aMilestone, aElement));
}
void SMILTimeContainer::ClearMilestones() {
MOZ_ASSERT(!mHoldingEntries);
mMilestoneEntries.Clear();
}
bool SMILTimeContainer::GetNextMilestoneInParentTime(
SMILMilestone& aNextMilestone) const {
if (mMilestoneEntries.IsEmpty()) return false;
SMILTimeValue parentTime =
ContainerToParentTime(mMilestoneEntries.Top().mMilestone.mTime);
if (!parentTime.IsDefinite()) return false;
aNextMilestone = SMILMilestone(parentTime.GetMillis(),
mMilestoneEntries.Top().mMilestone.mIsEnd);
return true;
}
bool SMILTimeContainer::PopMilestoneElementsAtMilestone(
const SMILMilestone& aMilestone, AnimElemArray& aMatchedElements) {
if (mMilestoneEntries.IsEmpty()) return false;
SMILTimeValue containerTime = ParentToContainerTime(aMilestone.mTime);
if (!containerTime.IsDefinite()) return false;
SMILMilestone containerMilestone(containerTime.GetMillis(),
aMilestone.mIsEnd);
MOZ_ASSERT(mMilestoneEntries.Top().mMilestone >= containerMilestone,
"Trying to pop off earliest times but we have earlier ones that "
"were overlooked");
MOZ_ASSERT(!mHoldingEntries);
bool gotOne = false;
while (!mMilestoneEntries.IsEmpty() &&
mMilestoneEntries.Top().mMilestone == containerMilestone) {
aMatchedElements.AppendElement(mMilestoneEntries.Pop().mTimebase);
gotOne = true;
}
return gotOne;
}
void SMILTimeContainer::Traverse(
nsCycleCollectionTraversalCallback* aCallback) {
#ifdef DEBUG
AutoRestore<bool> saveHolding(mHoldingEntries);
mHoldingEntries = true;
#endif
const MilestoneEntry* p = mMilestoneEntries.Elements();
while (p < mMilestoneEntries.Elements() + mMilestoneEntries.Length()) {
NS_CYCLE_COLLECTION_NOTE_EDGE_NAME(*aCallback, "mTimebase");
aCallback->NoteXPCOMChild(static_cast<nsIContent*>(p->mTimebase.get()));
++p;
}
}
void SMILTimeContainer::Unlink() {
MOZ_ASSERT(!mHoldingEntries);
mMilestoneEntries.Clear();
}
void SMILTimeContainer::UpdateCurrentTime() {
SMILTime now = IsPaused() ? mPauseStart : GetParentTime();
MOZ_ASSERT(now >= mParentOffset,
"Container has negative time with respect to parent");
const auto updatedCurrentTime = CheckedInt<SMILTime>(now) - mParentOffset;
mCurrentTime = updatedCurrentTime.isValid()
? updatedCurrentTime.value()
: std::numeric_limits<SMILTime>::max();
}
void SMILTimeContainer::NotifyTimeChange() {
// Called when the container time is changed with respect to the document
// time. When this happens time dependencies in other time containers need to
// re-resolve their times because begin and end times are stored in container
// time.
//
// To get the list of timed elements with dependencies we simply re-use the
// milestone elements. This is because any timed element with dependents and
// with significant transitions yet to fire should have their next milestone
// registered. Other timed elements don't matter.
// Copy the timed elements to a separate array before calling
// HandleContainerTimeChange on each of them in case doing so mutates
// mMilestoneEntries.
nsTArray<RefPtr<mozilla::dom::SVGAnimationElement>> elems;
{
#ifdef DEBUG
AutoRestore<bool> saveHolding(mHoldingEntries);
mHoldingEntries = true;
#endif
for (const MilestoneEntry* p = mMilestoneEntries.Elements();
p < mMilestoneEntries.Elements() + mMilestoneEntries.Length(); ++p) {
elems.AppendElement(p->mTimebase.get());
}
}
for (auto& elem : elems) {
elem->TimedElement().HandleContainerTimeChange();
}
}
} // namespace mozilla