This change adds the simplest kind of incremental layout. When Servo
detects that all style changes only require a repaint, only run stacking
context tree and WebRender display list generation. This means that
these kind of restyles do not need a re-layout. Instead, the existing
box and fragment trees will be used and the styles of damaged nodes will
be updated in their box and fragment tree nodes.
This requires a new style repair DOM traversal for nodes that have had
their style damaged. In addition, careful accounting of all the places
where we store style must happen in order ot update those styles.
Testing: This is covered by existing WPT tests as it should not change
observable behavior.
We have created a test case which shows a 50% speedup when run
in Servo, even though there still a long way to go to match the speed
of other browsers:
https://gist.github.com/mrobinson/44ec87d028c0198917a7715a06dd98a0
Co-authored-by: Oriol Brufau <obrufau@igalia.com>
Signed-off-by: Martin Robinson <mrobinson@igalia.com>
Signed-off-by: Martin Robinson <mrobinson@igalia.com>
Co-authored-by: Oriol Brufau <obrufau@igalia.com>
`TextRun`s use their parent style to render. Previously, these styles
were cloned and stored directly in the box tree `TextRun` and resulting
`TextFragment`s. This presents a problem for incremental layout.
Wrapping the style in another layer of shared ownership and mutability
will allow updating all `TextFragment`s during repaint-only incremental
layout by simply updating the box tree styles of the original text
parents.
This adds a new set of borrows when accessing text styles, but also
makes it so that during box tree block construction
`InlineFormattingContext`s are created lazily and now
`InlineFormattingContextBuilder::finish` consumes the builder, making
the API make a bit more sense. This should also improve performance of
box tree block construction slightly.
Testing: This should not change observable behavior and thus is covered
by existing WPT tests.
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 change switches `offsetParent`, `offsetLeft`, etc queries to use
the BoxTree fragments instead of walking the entire fragment tree. In
addition, fragments are stored for columns and colgroups. In general,
this greatly simplifies the flow of the query and prevents having to do
expensive tree walks.
Testing: This change is covered by newly passing WPT tests and three new
failures:
- /css/filter-effects/backdrop-filter-edge-clipping-2.html
- /css/filter-effects/backdrop-filter-edge-mirror.html
- /css/filter-effects/backdrop-filter-edge-pixels-2.html
These failures are actually progressions, because now the references
start
to render properly whereas before they did not.
Fixes: This is part of #36525 and #36665.
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/positioning_fragment.rs (Browse further)