This patch (after stepping through the call graph) affects the following
places:
* CommonAnimationManager::GetAnimationsForCompositor, which is used
only by nsDisplayListBuilder::AddAnimationsAndTransitionsToLayer,
which already checks the individual animations (so really no change)
* AnimationPlayerCollection::CanThrottleAnimation
* ActiveLayerTracker::IsStyleAnimated
* nsLayoutUtils::HasAnimationsForCompositor
* nsLayoutUtils::HasAnimations (which is used only to check whether we
can make the 0-opacity optimization)
I believe it makes sense to change all of these locations (although in
the long term we want to throttle (or similar) more animations).
Without this patch, I believe we're forcing the creation of an opacity
layer because we think we have animations to send to it.
This patch adds a method for testing if an animation is "in play" which is
a term defined in the Web Animations spec. This is in preparation for removing
some slightly redundant code in IsRunning and aligning better with the spec.
In preparation for introducing IsInPlay (where "in play" is a term in the Web
Animations spec), this patch aligns the existing IsCurrent with the definition
in the spec that says an animation effect is only current if it is attached
to an animation (player in our current naming) that is not finished. In order
to ensure that we need to pass the animation/player into the method.
This actually changes the behavior of IsCurrent since now we will return false
for animations that are finished. As far as I can tell, all the call sites that
are requesting current animations should only be concerned with animations that
are actually running. If not, they need to be adjusted to look for animations
that are either current or in effect.
This patch extracts the logic for calculating animation styles from
AnimationPlayerCollection and puts the bulk of it into the Animation objects.
Some of the initial logic surrounding the animation player state (e.g. is it
paused or not, etc.) is put into AnimationPlayer.
In future we may shift this logic even further down to the AnimationEffect
objects but currently we don't create such objects unless necessary.
This patch adds a utility method to return if an animation is "in effect" or not
as defined by Web Animations:
http://w3c.github.io/web-animations/#in-effect
It also moves the utility method for querying if an animation is "current"
(IsCurrent) to the .cpp file since it is fairly long. (Bug 1046055 makes one of
the callers of IsCurrent inline-able which should offset any cost introduced by
this no longer being inline-able.)
This patch takes the StickyTimeDuration defined in the previous patch and
uses it within the calculation of animation timing for parameters that are
expected to be +/- Forever.
As the second step in dividing functionality between AnimationPlayer and
Animation, this patch moves the AnimationTiming member from AnimationPlayer to
Animation.
Most of this patch is simply moving code around. However, one significant
functional difference is that Animation::GetLocalTime() uses the mParentTime
member which is set when the Animation is updated by the player it is attached
to.
Other less significant differences are:
* AnimationPlayer::GetLocalTime is renamed to GetCurrentTimeDuration
In Web Animations, animation players have a (writeable) "current time" and
animations have a (read-only) "local time".
We would call the method simply "GetCurrentTime" (instead of
"GetCurrentTimeDuration") but GetCurrentTime is the name of the method used in
the content-facing API where it returns a double.
* "IsCurrent" is defined on both AnimationPlayer and Animation with the version
in AnimationPlayer serving mostly as a convenience shortcut to the version on
Animation.
* Animation::GetComputedTiming (previously on AnimationPlayer) now makes the
timing parameter optional since most of the time it is not needed.
As the first step in dividing the functionality currently contained in
AnimationPlayer between AnimationPlayer and Animation this patch moves the set
of keyframe properties to the Animation.
These properties are returned from the Animation by a couple of Properties()
methods that provide direct access to the member variable. In future it is
anticipated that the non-const version will be replaced with an appropriate
setter function. This will likely happen when we implement a separate
KeyframeEffect object as defined by the Web Animations API.
With regards to error checking, nsAnimationManager checks the result of
AnimationPlayer::GetSource() and handles the case where it is nullptr.
nsTransitionManager, however, simply asserts that GetSource() is never null much
like it also asserts that there is only one property with one segment in the
animation. Eventually this code should be made more generic which will probably
happen in bug 999927.
This patch makes AnimationPlayers pass their current time down to the Animation
they are playing.
Since all Animations need from their players is their time, this avoids adding
a pointer back to their AnimationPlayer.
L. David Baron
Brian Birtles
Boris Zbarsky
Carsten "Tomcat" Book
Nicholas Nethercote
Andrew McCreight
David Zbarsky