In the IPC Animation struct used in layers code we have a member called
'numIterations' where 'iterate forever' is represented by -1.
In layout/style however we have an AnimationTiming struct with an
mIterationCount member where 'iterate forever' is represented by
NS_IEEEPositiveInfinity().
This patch renames 'numIterations' to 'iterationCount' and uses infinity to
represent 'iterate forever'.
This patch simply moves the code from ElementAnimations to ElementAnimation so
that it can later be used in transitions code and so we can later move
EnsureStyleRuleFor to ElementAnimation.
This patch makes ElementAnimations::GetPositionInIteration return
a ComputedTiming object instead of just a time portion (time fraction).
Since the ComputedTiming object includes phase information, we can fix those
parts of EnsureStyleRule and GetEventsAt that were temporarily using the time
portion to guess if the animation might have finished or not.
This patch moves event queuing out of EnsureStyleRuleFor into a separate method.
This is a preparatory step towards making GetPositionInIteration into a more
generic method for calculating the current time fraction.
In order to achieve this, GetPositionInIteration needs to be able to calculate
the correct time portion for times outside the range [0, 1] even when it is not
passed a ElementAnimation object. Specifically, it needs the fill mode of the
animation to be passed in.
(Rather than using FillForwards/FillBackwards this patch just compares the
NS_STYLE_ANIMATION_FILL_MODE_* values directly but FillForwards/FillBackwards
are restored in a subsequent patch when they are added to the struct used to
lump the timing parameters together.)
There are a number of places where positionInIteration is used to determine if
the current sample occurs in the active phase or after. This is sub-optimal but
is fixed in a subsequent patch in this series.
The actual work of removing event queuing from GetPositionInIteration is
deferred to a subsequent patch in order to keep the changes as small as
possible. This patch simply makes separate calls to GetPositionInIteration for
interpolating and for event queuing.
When restoring the refresh driver after testing we can arrive at a situation
where a layer has an animation that has yet to start. However, calling
ElementAnimations::GetPositionInIteration with a negative value from the
compositor thread is an error.
This patch detects animations on the compositor thread that are yet-to-start and
skips them when sampling. It also moves the activeAnimations = true line up as
otherwise we would need special logic to wake up the compositor after the delay
has finished.
If we've applied an async transform to an empty container layer (e.g. a layer
that corresponds to an nsDisplayScrollInfo display item), don't use that
transform on the corresponding scrollbar.
Fixed layers are relative to their nearest scrollable ancestor, so when we
encounter a scrollable layer in AlignFixedAndStickyLayers, reset the transform
and sub-tree root to start from that scrollable layer.
This fixes async scrolling of the fixed header in the Firefox marketplace on
B2G.
This adds a new eCSSUnit_SharedList type for nsCSSValue, which is a
reference counted object that contains an nsCSSValueList. We need this
so that nsStyleDisplay::mSpecifiedTransform can hold a strong reference
to a specified transform list value. When 'transform' is specified
using a variable reference, the resulting nsCSSValue does not stick
around in the Declaration object, so we wouldn't be guaranteed that
it lives long enough for nsStyleDisplay to keep referencing it.
The bulk of this patch is fixing up pieces of code that infer the resolution
as the inverse of the scaling transform on the root layer. This used to be
how various bits of gfx code obtained the resolution, but now that we can set
the resolution on the actual presShell that contains the content, we can also
just read the resolution from the FrameMetrics directly.
Since the CSS transform includes a 1/resolution scaling factor, the translation
amount in the async transform is now in LayoutDevicePixels instead of LayerPixels.
The shadow tree transform is now effectively:
(1/resolution * rest of CSS transform * async translation * async resolution)
Whereas before it was
(async translation * async resolution * 1/resolution * rest of CSS transform)
Bug 876542 introduces a patch that reworks how we maintain the position of
fixed position layers, but didn't handle overscroll/zoom. This restores the old
behaviour in this situation.
Restore the reconciliation between content document fixed position margins at
render time and the fixed layer margins as retrieved via SyncViewportInfo
during async panning/zooming.
