Once we support arbitrary timelines which can return null current time values,
the local time of an animation can also become null so this patch updates
ElementAnimation::GetLocalTimeAt to return a Nullable<TimeDuration>.
Doing this also allows us to pass the result of GetLocalTimeAt directly to
GetComputedTimingAt.
As part of supporting arbitrary timelines, we'd like to pass null times to the
function that calculates computed timing. Incidentally, this also provides
a means for evaluating calculating timing parameters that are independent of the
current time (currently only the active duration) without requiring a valid
time.
This patch updates the signature of ElementAnimation::GetComputedTimingAt to
take a nullable time duration.
We use the Nullable wrapper to represent null TimeDurations since, unlike,
TimeStamp, TimeDuration does not include a null state.
In order to support arbitrary timelines which may provide a "null" current time,
we need a suitable value to return from GetComputedTimingAt for the animation's
phase when the timeline time is null.
This patch introduces a null animation phase for this purpose.
This patch adds the WebIDL definitions and implementation of
getAnimationPlayers on Element.
It does not include the full definition of AnimationPlayer but only readonly
versions of the currentTime and startTime attributes since these are easy
to implement and enable identifying the different animations that are returned
for the sake of testing.
Web Animations defines getAnimationPlayers as only returning the animations that
are either running or will run in the future (known as "current" animations).
This will likely change since it seems desirable to be able query animations
that have finished but are applying a forwards fill. For now, however, this
patch makes us only return animations that have not finished.
This patch also removes an assertion in ElementAnimation::GetLocalTime that
would fail if called on a finished transition. This assertion is no longer
necessary since an earlier patch in this series removed the overloading of
the animation start time that meant calling this on a finished transition
was unsafe. Furthermore, this assertion, if it were not removed, would fail
if script holds onto a transition and queries its start time after it
completed.
This patch simply factors out the conversion from a TimeStamp value to
a nullable-double value relative to the start of the timeline. This is so that,
in a subsequent patch, this functionality can be reused by ElementAnimation
when it reports its start time (which is currently recorded as a TimeStamp).
AnimationTimeline::GetCurrentTime returns the time value of the timeline as
a double. For internal calculations however it is more useful to get this as
a mozilla::TimeStamp.
This patch splits the calculation of the current time into two stages:
calculation as a timestamp then conversion to a double.
When we expose ElementAnimation objects to script they need to have a parent
object so they can be associated with a Window.
This patch adds a pointer from an ElementAnimation to its AnimationTimeline.
When transitions finish, we keep them around for one additional throttle-able
tick to provide correct behavior for subsequent transitions that may be
triggered. Prior to this patch we did this by overloading the start time of the
animation and setting it to null in this case.
However, if we begin returning ElementAnimation objects to script, script can
hold on to those objects and query their start time even after they are
finished. Therefore we need another means of marking finished transitions that
doesn't clobber the start time field.
This patch introduces a new boolean member for marking such transitions.
While we're touching IsFinishedTransition we also take the chance to tidy up one
of the call sites, namely IsCurrentAt, to make the logic a little easier to
follow.
Brian Birtles
Anthony Jones
Andrew McCreight
Bobby Holley
Wes Kocher
Ralph Giles
Bas Schouten
Nikhil Marathe
Christoph Kerschbaumer
Terrence Cole
Sid Stamm
Ehsan Akhgari
Sotaro Ikeda
Randell Jesup
Jed Davis