Add slow path for hit testing of iframe behind positioned content layer
Fixes browser.html blocker #8759. r? @pcwalton
This adds a slow path for cases where the compositor's layer-based hit testing is incorrect. If the script task discovers that a mouse event should have been dispatched to an iframe, it bounces the event back to the constellation to be forwarded to the correct pipeline.
This isn't terribly slow (on the slow path, it adds one extra round-trip message between script and constellation), but if we want to optimize this better we could instead replace the compositor's layer hit testing with display list hit testing in the paint task. This would be a more complicated change that I think we should save for a follow-up.
This only fixes mouse input for now. A basically-identical change will be needed for touch-screen input, whether we stick with this approach or switch to the paint task.
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Fixes#8759.
This adds a slow path for cases where the compositor's layer-based hit testing
is incorrect. To optimize for this case, we could instead replace the
layer hit testing with display-list hit testing done in the paint task.
Implement Get Element Attribute WebDriver command
This intentionally doesn't implement the special handling for boolean
attributes yet, since that requires some kind of exhaustive list of all
such attributes
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Supports sending keys to an element. The specification here is still
rather unfinished so the error handling and so on in this code will
need iteration as it becomes clearer what the expected behaviour is.
Instead of always promoting iframes to StackingContexts, integrate them
into the display list. This prevents stacking bugs when
non-stacking-context elements should be drawn on top of iframes.
To accomplish this, we add another step to ordering layer creation,
where LayeredItems in the DisplayList are added to layers described by
the LayerInfo structures collected at the end of the DisplayList.
Unlayered items that follow these layered items are added to
synthesized layers.
Another result of this change is that iframe layers can be positioned
directly at the location of the iframe fragment, eliminating the need
for the SubpageLayerInfo struct entirely.
Iframes are the first type of content treated this way, but this change
opens up the possibility to properly order canvas and all other layered
content that does not create a stacking context.
Fixes#7566.
Fixes#7796.
Remove constellation round trip for subpage mapping in compositor.
This makes use of the new functionality that allows iframes to generate their own pipeline IDs in order to remove any knowledge of subpage ids from the compositor.
(This is the first of several commits removing subpage from parts of servo).
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This makes use of the new functionality that allows iframes to generate their own pipeline IDs in order to remove any knowledge of subpage ids from the compositor.
(This is the first of several commits removing subpage from parts of servo).
Make it possible for iframes to create their own pipeline ID.
This doesn't change any functionality, but it's the first step towards removing SubpageId.
Adding this change now will allow us to gradually change over code referencing subpage id rather than in one massive PR.
Introduces a namespace for pipeline ID generation - there is a namespace for the constellation thread, and one per script thread.
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This doesn't change any functionality, but it's the first step towards removing SubpageId.
Adding this change now will allow us to gradually change over code referencing subpage id rather than in one massive PR.
Introduces a namespace for pipeline ID generation - there is a namespace for the constellation thread, and one per script thread.
StackingContexts are added to layers when it is necessary to maintain
their ordering on top of other layered StackingContexts. Instead of
tracking the information about a layer scattered around into different
structs, combine it all into LayerInfo. LayerInfo will be used in the
future to hold layer information for DisplayItems that are layerized
independently of StackingContexts.
each iframe.
The old code that attempted to do this during layout wasn't able to work
for multiple reasons: it couldn't know where the iframe was going to be
on the page (because of nested iframes), and at the time it was building
the display list for a fragment it couldn't know where that fragment was
going to be in page coordinates.
This patch rewrites that code so that both the sizes and positions of
iframes are determined by the compositor. Layout layerizes all iframes
and marks the iframe layers with the appropriate pipeline and subpage
IDs so that the compositor can place them correctly. This approach is
similar in spirit to Gecko's `RefLayer` infrastructure. The logic that
determines when it is time to take the screenshot for reftests has been
significantly revamped to deal with this change in delegation of
responsibility.
Additionally, this code removes the infrastructure that sends layout
data back to the layout task to be destroyed, since it is now all
thread-safe and can be destroyed on the script task.
The failing tests now fail because of a pre-existing bug related to
intrinsic heights and borders on inline replaced elements. They happened
to pass before because we never rendered the iframes at all, which meant
they never had a chance to draw the red border the tests expect to not
render!
Closes#7377.
Ensure that animations expire correctly and stop compositing occurring after they finish.
There were two problems here:
(1) The animation state update function was only called when nodes were dirty or there were new animations.
(2) When all animations for a node expired, the entry from the hash table was not removed.
The result was that once an animation began, the compositor would be running as fast as it can forever.
Fixes#7721.
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There were two problems here:
(1) The animation state update function was only called when nodes were dirty or there were new animations.
(2) When all animations for a node expired, the entry from the hash table was not removed.
The result was that once an animation began, the compositor would be running as fast as it can forever.
Fixes#7721.
Currently pseudo-elements, like the fragments created for ::before and
::after, with layers will have the same LayerId as the body of their
owning fragments. Instead all LayerIds should be unique.
Fixes#2010.
StackingContexts that should be painted on top of StackingContexts that
are already layerized should automatically get their own layer. This
will ensure proper painting order.
Have PaintLayers own StackingContexts instead of the opposite
Previously, StackingContexts might have a PaintLayer. We switch the
ownership, for several reasons:
* We want PaintLayers to potentially contain something other
than a StackingContext soon.
* We want to delay the creation of PaintLayers until the last
minute, so that we can synthesize new layers for sandwiched
content.
This commit also implements the second goal. Instead of creating
PaintLayers during layout itself, wait until we are sorting and
layerizing a completed DisplayList.
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Previously, StackingContexts might have a PaintLayer. We switch the
ownership, for several reasons:
* We want PaintLayers to potentially contain something other
than a StackingContext soon.
* We want to delay the creation of PaintLayers until the last
minute, so that we can synthesize new layers for sandwiched
content.
This commit also implements the second goal. Instead of creating
PaintLayers during layout itself, wait until we are sorting and
layerizing a completed DisplayList.
