When a stacking-context is not positioned, its z-index should be
ignored. This is per CSS 2 9.9.1. The only exception to this is when
the z-index is applied to an element with display: flex | inline-flex.
inline-flex does not appear to be implemented at this time so we only
do this for flex.
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).
Rework how StackingContexts are dynamically added to layers
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.
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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.
Simplify stacking context creation
Have Fragment::create_stacking_context understand which stacking
contexts need layers and which do not. This simplifies the way it is
called and eliminates a bunch of code.
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Have Fragment::create_stacking_context understand which stacking
contexts need layers and which do not. This simplifies the way it is
called and eliminates a bunch of code.
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.
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.
Current implementation is taking <number> type as parameter so skew()
does not work properly. Let the skew() to get <angle> as specification
described.
Fixes#6237.
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.
margins.
* The code that attempted to strip out borders that span multiple
fragments in the same element could go wrong if fragments were
stripped out due to text clumping or whitespace stripping. This patch
rewrites that code to maintain flags in the inline fragment context
specifying whether the node is the beginning or end of the element.
Not only is this easier to maintain, it's closer in spirit to what roc
originally suggested two years ago: it's isomorphic to "begin element,
end element" markers for inline layout.
* Padding and margins for spans containing inline-blocks are now
properly handled via a division of labor between the `InlineBlock`
fragment and the `BlockFlow` that represents the inline-block.
* Unscanned text fragments may not be joined together into a text run if
borders, padding, or margins separate them.
Because Servo now matches the rendering of Gecko and WebKit on the
`input_button_margins_a` reftest, I had to modify it to add some
vertical alignment.
The combined effect of all of these fixes places "Advertising" on the
right place on google.com.
account.
This necessitated changing overflow to be calculated by the parent flow
if relatively positioned children are present. That is because the
overflow regions cannot be calculated without knowing relative offsets,
which themselves cannot be calculated without knowing the parent size
(because of percentages). To accomplish this without sacrificing
parallelism in the non-relative case, this patch splits overflow into
"early" and "late" computation. Late overflow computation cannot be
parallelized across children, while early overflow computation can.
Makes the "Apple Music" text show up over the full-bleed promotional
background on apple.com.
layers in the fragment, so that it can be activated when we're forcing
the creation of extra layers due to positioned descendants that
themselves have layers.
The newly failing tests were tests that accidentally passed due to
incorrect stacking order.
Closes#7281.
Known issues:
* Display list optimization can sometimes optimize out elements that
should be shown. This affects the Enyo demo.
* The `overflow: scroll` container doesn't clip the inner layer properly
when borders, border radius, etc. are present.
* `overflow-x: scroll` and `overflow-y: scroll` don't work individually;
elements are scrolled all at once.
* Scrolling only works on absolutely-positioned elements.
At this point the only thing it does is to try to avoid adding display
items that are outside the root scrollable area, which is both wrong
(since it's incompatible with having scrollable areas outside the root)
and is useless (because we have displayports now).
To actually make the multiprocess communication work, we'll need to
reroute the task creation to the pipeline or the compositor. But this
works as a first step.
The idea here is to land this before making images and canvas IPC-safe,
because this will shake out bugs relating to the shared memory. There
are currently test timeouts that are preventing multiprocess images and
canvas from landing, and I believe those are due to the inefficiency of
sending large amounts of data in the unoptimized builds we test with. By
moving to shared memory, this should drastically reduce the number of
copies and `serde` serialization.
Under the hood, this uses Mach OOL messages on Mac and temporary
memory-mapped files on Linux.
This commit introduces the `serde` dependency, which we will use to
serialize messages going between processes in multiprocess Servo.
This also adds a new debugging flag, `-Z print-display-list-json`,
allowing the output of display list serialization to be visualized.
This will be useful for our experiments with alternate rasterizers.
