Remove DisplayListBuildingResult
Always produce a DisplayList when processing nodes for display list
construction. StackingContexts are now added to the positioned content
section of DisplayLists. This makes the code a bit simpler and opens up
the possibility of producing a StackingContext in another section of
the DisplayList. This doesn't change behavior, but is a cleanup
prerequisite for proper inline stacking context support.
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This flag is no longer necessary, because stacking contexts can now
create layers lazily for content that needs to be stacked above a
layer. This should reduce the number of layers on pages, hopefully
reducing overdraw.
Always produce a DisplayList when processing nodes for display list
construction. StackingContexts are now added to the positioned content
section of DisplayLists. This makes the code a bit simpler and opens up
the possibility of producing a StackingContext in another section of
the DisplayList. This doesn't change behavior, but is a cleanup
prerequisite for proper inline stacking context support.
Mix stacking contexts into the positioned content list
Sometimes positioned content needs to be layered on top of stacking
contexts. The layer synthesis code can do this, but the current design
prevents it because stacking contexts are stored in a separate struct
member. In order to preserve tree order, mix stacking contexts into the
positioned content list, by adding a new StackingContextClass
DisplayItem. Such items do not have a base DisplayItem.
In some ways this simplifies the code, because we no longer have to
have a separate code path in the StackingContextLayerCreator.
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Sometimes positioned content needs to be layered on top of stacking
contexts. The layer synthesis code can do this, but the current design
prevents it because stacking contexts are stored in a separate struct
member. In order to preserve tree order, mix stacking contexts into the
positioned content list, by adding a new StackingContextClass
DisplayItem. Such items do not have a base DisplayItem.
In some ways this simplifies the code, because we no longer have to
have a separate code path in the StackingContextLayerCreator.
Fixes#7779.
Fixes#7983.
Fixes#8122.
Fixes#8310.
Flows never care about their own text-align, only the text-align of
their parent; change the text-align flags to account for that. Make the
"align descendants" rule use the flags instead of the current node's style.
Fixes#7301.
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.
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.
layout: Improve our handling of inline absolute containing blocks.
Several issues are addressed in this commit:
* Inline flows now bubble up their absolute descendants instead of
making the inline flow the containing block for them. (In the future,
we will need to make the inline flow *sometimes* be the containing
block for them, but for now it improves sites to unconditionally
bubble up.)
* Fragments now look at their inline fragment context to determine
whether they are positioned.
* Inline flows now push the stacking-relative position of the absolute
containing block down to their inline-block fragments.
* Inline absolute hypothetical fragments can be containing blocks.
* Fixes the logic in
`containing_block_range_for_flow_surrounding_fragment_at_index`. The
condition to determine whether fragments are positioned was inverted!
* `Descendants`/`AbsDescendants` has been refactored in order to become
more friendly to inline absolute containing blocks in the future.
Improves the inline position of the green drop-down arrow in the Google
SERPs. (The block position is still wrong.)
r? @mbrubeck
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Several issues are addressed in this commit:
* Inline flows now bubble up their absolute descendants instead of
making the inline flow the containing block for them. (In the future,
we will need to make the inline flow *sometimes* be the containing
block for them, but for now it improves sites to unconditionally
bubble up.)
* Fragments now look at their inline fragment context to determine
whether they are positioned.
* Inline flows now push the stacking-relative position of the absolute
containing block down to their inline-block fragments.
* Inline absolute hypothetical fragments can be containing blocks.
* Fixes the logic in
`containing_block_range_for_flow_surrounding_fragment_at_index`. The
condition to determine whether fragments are positioned was inverted!
* `Descendants`/`AbsDescendants` has been refactored in order to become
more friendly to inline absolute containing blocks in the future.
Improves the inline position of the green drop-down arrow in the Google
SERPs. (The block position is still wrong.)
The failing `float-applies-to-*` CSS 2.1 tests never really should have
been passing in the first place; they depend on floats inside
fixed-layout tables working properly, which they don't.
Closes#6078.
Closes#6709.
Closes#6858.
It's not possible to correctly determine during the css cascade whether the container height
is explicitly specified. Additionally, the spec https://drafts.csswg.org/css2/visudet.html#the-height-property
says this should affect the *used* height, rather than the computed height.
This significantly improves the layout in #6643.
