In support of this goal, the layout thread collects information about
CSS images that are missing image data and hands it off to the script
thread after layout completes. The script thread stores a list of
nodes that will need to be reflowed after the associated network
request is complete. The script thread ensures that the nodes are
not GCed while a request is ongoing, which the layout thread is
incapable of guaranteeing.
The image cache's API has also been redesigned in support of this
work. No network requests are made by the new image cache, since it
does not possess the document-specific information necessary to
initiate them. Instead, there is now a single, synchronous
query operation that optionally reserves a slot when a cache
entry for a URL cannot be found. This reserved slot is then
the responsibility of the queryer to populate with the contents
of the network response for the URL once it is complete. Any
subsequent queries for the same URL will be informed that the
response is pending until that occurs.
The changes to layout also remove the synchronous image loading
code path, which means that reftests now test the same code
that non-test binaries execute. The decision to take a screenshot
now considers whether there are any outstanding image
requests for layout in order to avoid intermittent failures in
reftests that use CSS images.
It could be used to have mutable JSVal fields without GC barriers.
With the removal of that trait, MutHeap and MutNullableHeap can respectively
be replaced by MutJS and MutNullableJS.
Urlmageddon
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Still needs a bunch of code in net to be converted in order to get more
advantage of this for images and stuff, but meanwhile this should help quite a
bit with #13778.
Still wanted to get this in.
r? @SimonSapin
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WebRender is an experimental GPU accelerated rendering backend for Servo.
The WebRender backend can be specified by running Servo with the -w option (otherwise the default rendering backend will be used).
WebRender has many bugs, and missing features - but it is usable to browse most websites - please report any WebRender specific rendering bugs you encounter!
Updated string_cache, html5ever, xml5ever and selectors in Cargo.toml files and Cargo.lock.
Removed references to string_cache_plugin.
Import atom! and ns! from string_cache.
Replaced ns!("") by ns!().
Replaced ns!(XML) and co by ns!(xml) and co.
Replaced atom!(foo) by atom!("foo").
Replaced Atom::from_slice by Atom::from.
Replaced atom.as_slice() by &*atom.
Simplify implementation of '<canvas>' 'width' and 'height' attributes.
Strictly speaking, this affects correctness for extremely large width and height values... but that's unlikely to matter in practice.
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This should make it somewhat easier to experiment with alternative
representations in the future. To reduce churn, this commit leaves the String
field public, though.
Also, this will allow us to use the default String type to represent the IDL
USVString type, which explicitly forbids unpaired surrogates, ans as such is
a better match to the Rust String type.
