Previously, after a layout was finished (or skipped in the case of
repaint-only layout), both the stacking context tree and display list
were built. In the case of repaint-only layout, we should be able to
skip the reconstruction of the stacking context tree and only do display
list building.
This change does that, also generally cleaning and up and clarifying the
data structure used during this phase of layout. This opens up the
possibility of a new kind of incremental layout that does both repaint
and a rebuild of the stacking context tree.
On the blaster.html test case[^1], this reduces tightly-measured layout
time from ~45-50 milliseconds to ~25-30 milliseconds on my M3.
[^1]: https://gist.github.com/mrobinson/44ec87d028c0198917a7715a06dd98a0
Testing: There are currently no performance tests for layout. :( This
should
not modify the results of WPT tests.
Signed-off-by: Martin Robinson <mrobinson@igalia.com>
Co-authored-by: Oriol Brufau <obrufau@igalia.com>
Instead of resolving the canvas background properties (essentially
keeping a possible reference to the `<body>`'s style) during fragment
tree construction, wait until painting to possibly find the style on an
appropriate `<body>` fragment. This is possible now because `Fragment`
keeps a list of flags with relevant information about the root and
`<body>` elements.
A benefit of this approach is that styles aren't cached in the fragment
tree, which would be problematic for incremental layout. In addition,
the old code was making an effort to transform the `<body>`'s background
by the root element's transform. Only Safari does this and there was
a resolution the WG that this should not happen in
https://github.com/w3c/csswg-drafts/issues/6683.
Testing:
- `/css/css-transforms/transform-translate-background-001.html`
- `/css/css-transforms/transform-translate-background-002.html`
- `/css/CSS2/floats/float-root.html`
Fixes: #30475.
Closes: #30569.
Signed-off-by: Martin Robinson <mrobinson@igalia.com>
Co-authored-by: Oriol Brufau <obrufau@igalia.com>
In the scrollable overflow calcutation, apply CSS transforms to boxes
and scrollable overflow of the descendant. Clip unreachable scrollable
overflow according to it's block start and inline start scrolling
direction. And, renamed `Fragment::scrolling_overflow` to
`Fragment::scrolling_overflow_for_parent` as it was calculating the
scrolling overflow contribution from a child.
Add several WPT tests, testing the transform interaction `rotate`,
`scale`, and `skew` with scrollable overflow. There are several WPT test
that are testing the interaction that not expected from current browsers
implementation according to the spec.
Testing: Existing and new WPT.
Fixes: #36031
---------
Signed-off-by: stevennovaryo <steven.novaryo@gmail.com>
This is a followup to #36629, continuing to implement script-based
layout queries using the `Fragment`s attached to the `BoxTree`. In this
change, geometry queris (apart from parent offset) are calculated using
`Fragment`s hanging of the `BoxTree`.
In order to make this work, all `Fragment`s for inlines split by blocks,
need to be accessible in the `BoxTree`. This required some changes to
the way that box tree items were stored in DOM `BoxSlot`s. Now every
inline level item can have more than a single `BoxTree` item. These are
carefully collected by the `InlineFormattingContextBuilder` -- currently
a bit fragile, but with more documentation.
Testing: There are tests for these changes.
Signed-off-by: Martin Robinson <mrobinson@igalia.com>
Co-authored-by: Oriol Brufau <obrufau@igalia.com>
When doing any kind of query, up until now, containing block rectangles
were calculated by walking the `FragmentTree` until the node being
queried was found. In order to make possible answering queries without
walking the `FragmentTree`, `Fragment`s need to cache their cumulative
containing block rectangles.
This change adds a new `FragmentTree` pass (during construction) that
takes care of calculating and caching these values. The new cached value
is used during resolved style queries and also scrolling area queries
(with the idea that all queries will eventually use them).
In addition, extra `FragmentTree` walks used for cancelling animations
for elements no longer in the `FragmentTree` are integrated into this
new traversal.
Testing: Covered by existing WPT tests.
Signed-off-by: Martin Robinson <mrobinson@igalia.com>
Co-authored-by: Oriol Brufau <obrufau@igalia.com>
Now that legacy layout has been removed, the name `layout_2020` doesn't
make much sense any longer, also it's 2025 now for better or worse. The
split between the "layout thread" and "layout" also doesn't make as much
sense since layout doesn't run on it's own thread. There's a possibility
that it will in the future, but that should be something that the user
of the crate controls rather than layout iself.
This is part of the larger layout interface cleanup and optimization
that
@Looriool and I are doing.
Testing: Covered by existing tests as this is just code movement.
Signed-off-by: Martin Robinson <mrobinson@igalia.com>
2025-04-19 10:17:03 +00:00
Renamed from components/layout_2020/fragment_tree/fragment_tree.rs (Browse further)
