nsIStyleRule*
nsAnimationManager::CheckAnimationRule(nsStyleContext* aStyleContext,
mozilla::dom::Element* aElement)
{
if (!mPresContext->IsProcessingAnimationStyleChange()) {
if (!mPresContext->IsDynamic()) {
// For print or print preview, ignore animations.
return nullptr;
}
// 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();
ElementAnimations *ea =
GetElementAnimations(aElement, aStyleContext->GetPseudoType(), false);
if (!ea &&
disp->mAnimationNameCount == 1 &&
disp->mAnimations[0].GetName().IsEmpty()) {
return nullptr;
}
// build the animations list
InfallibleTArray<ElementAnimation> newAnimations;
BuildAnimations(aStyleContext, newAnimations);
if (newAnimations.IsEmpty()) {
if (ea) {
ea->Destroy();
}
return nullptr;
}
TimeStamp refreshTime = mPresContext->RefreshDriver()->MostRecentRefresh();
if (ea) {
ea->mStyleRule = nullptr;
ea->mStyleRuleRefreshTime = TimeStamp();
ea->UpdateAnimationGeneration(mPresContext);
// 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
// (or potentially optimize BuildAnimations to avoid rebuilding it
// in the first place).
if (!ea->mAnimations.IsEmpty()) {
for (uint32_t newIdx = 0, newEnd = newAnimations.Length();
newIdx != newEnd; ++newIdx) {
ElementAnimation *newAnim = &newAnimations[newIdx];
// Find the matching animation with this name in the old list
// of animations. Because of this code, they must all have
// the same start time, though they might differ in pause
// state. So if a page uses multiple copies of the same
// animation in one element's animation list, and gives them
// different pause states, they, well, get what they deserve.
// We'll use the last one since it's more likely to be the one
// doing something.
const ElementAnimation *oldAnim = nullptr;
for (uint32_t oldIdx = ea->mAnimations.Length(); oldIdx-- != 0; ) {
const ElementAnimation *a = &ea->mAnimations[oldIdx];
if (a->mName == newAnim->mName) {
oldAnim = a;
break;
}
}
if (!oldAnim) {
continue;
}
newAnim->mStartTime = oldAnim->mStartTime;
newAnim->mLastNotification = oldAnim->mLastNotification;
if (oldAnim->IsPaused()) {
if (newAnim->IsPaused()) {
// Copy pause start just like start time.
newAnim->mPauseStart = oldAnim->mPauseStart;
} else {
// Handle change in pause state by adjusting start
// time to unpause.
newAnim->mStartTime += refreshTime - oldAnim->mPauseStart;
}
}
}
}
} else {
ea = GetElementAnimations(aElement, aStyleContext->GetPseudoType(),
true);
}
ea->mAnimations.SwapElements(newAnimations);
ea->mNeedsRefreshes = true;
ea->EnsureStyleRuleFor(refreshTime, mPendingEvents, false);
CheckNeedsRefresh();
// We don't actually dispatch the mPendingEvents now. We'll either
// dispatch them the next time we get a refresh driver notification
// or the next time somebody calls
// nsPresShell::FlushPendingNotifications.
if (!mPendingEvents.IsEmpty()) {
mPresContext->Document()->SetNeedStyleFlush();
}
}
return GetAnimationRule(aElement, aStyleContext->GetPseudoType());
}
