Because this is a bottom-up traversal it can generates flows and throw them away. To prevent that, this cascades an internal `-servo-under-display-none` property and then checks that during flow construction. Fixes#1536.
speculation code.
The old code tried to do the speculation as a single bottom-up pass
after intrinsic inline-size calculation, which was unable to handle
cases like this:
<div>
<div style="float: left">Foo</div>
</div>
<div>
<div style="overflow: hidden">Bar</div>
</div>
No single bottom-up pass could possibly handle this case, because the
inline-size of the float flowing out of the "Foo" block could never make
it down to the "Bar" block, where it is needed for speculation.
On the pages I tried, this regresses layout performance by 1%-2%.
I first noticed this breaking some pages, like the Google SERPs, several
months ago.
some object needs to be repainted.
Reduces CPU usage when mousing over simple documents. (More complex
documents tend to trigger unnecessary reflow bugs and so still have high
CPU.)
Part of #9999.
bottom-up pass.
Right now, the only reason that overflow calculation works is that we
rely on script inducing extra reflows that are sent for display. This
was preventing #10021 from landing.
This change regresses layout performance by about 1% in my tests.
Fixes#7797 properly.
Instead of producing a tree of stacking contexts, display list
generation now produces a flat list of display items and a tree of
stacking contexts. This will eventually allow display list construction
to produce and modify WebRender vertex buffers directly, removing the
overhead of display list conversion. This change also moves
layerization of the display list to the paint thread, since it isn't
currently useful for WebRender.
To accomplish this, display list generation now takes three passes of
the flow tree:
1. Calculation of absolute positions.
2. Collection of a tree of stacking contexts.
3. Creation of a list of display items.
After collection of display items, they are sorted based upon the index
of their parent stacking contexts and their position in CSS 2.1
Appendeix E stacking order.
This is a big change, but it actually simplifies display list generation.
This is unfortunate, but making that useful would require parameterizing
`SharedLayoutContext` and `LayoutContext` depending on the
`SelectorImpl` (which is a **huge** work right now).
Probably the easier way to do it, and probably the one that keeps the
layout code more legible, and since there won't be multiple
implementations at the same compilation unit, would be "defining" a
default implementation for layout via feature flags.
That should allow us to remove the components/style/servo.rs file.
This commit refactors the style crate to be completely independent of
the actual implementation and pseudo-elements supported.
This also adds a gecko backend which introduces parsing for the
anonymous box pseudo-elements[1], although there's still no way of
querying them.
https://mxr.mozilla.org/mozilla-central/source/layout/style/nsCSSAnonBoxList.h
We do a few things-here:
* Hoist non-layout-dependent fields in SharedLayoutData and LocalLayoutData into style/.
* Hoist parts of css/matching.rs into style/.
* Hoist parts of layout/animation.rs into style/animation.rs.
* Remove the duplicated-but-slightly-different definition of OpaqueNode.
This patch does a number of things, unfortunately all at once:
* Hoists a large subset of the layout wrapper functionality into the style system.
* Merges TElementAttributes into the newly-created TElement.
* Reorganizes LayoutData by style vs layout, and removes LayoutDataShared.
* Simplifies the API for borrowing style/layout data.
There's still more to do to make the style system usable standalone, but
this is a good start.
There wasn't a good way to split this up, unfortunately.
With this change, the only remaining usage of the Servo-specific structures is
in layout_task, where the root node is received from the script task. \o/
Clean up restyle damage after it no longer applies
BUBBLE_ISIZES and REPAINT can become "stuck" on in the default Servo
configuration once they are activated. This is solved by removing these
damage bits after they no longer apply. There isn't a good way to test
this, other than noting that it doesn't break any existing CSS tests.
This will become more important in the future as the REPAINT bit is used
to implement display list patching.
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BUBBLE_ISIZES and REPAINT can become "stuck" on in the default Servo
configuration once they are activated. This is solved by removing these
damage bits after they no longer apply. There isn't a good way to test
this, other than noting that it doesn't break any existing CSS tests.
This will become more important in the future as the REPAINT bit is used
to implement display list patching.
This isn't doing anything right now, and we're not even setting it properly
in dirty_impl the |dirty_subtree(self)| was causing us to hit the skip case
for step 3.
