Instead of the tricky `LayoutRPC` interface, query layout using the
`Layout` trait. This means that now queries will requires calling layout
and then running the query. During layout an enum is used to indicate
what kind of layout is necessary.
This change also removes the mutex-locked `rw_data` from both layout
threads. It's no longer necessary since layout runs synchronously. The
one downside here is that for resolved style queries, we now have to
create two StyleContexts. One for layout and one for the query itself.
The creation of this context should not be very expensive though.
`LayoutRPC` used to be necessary because layout used to run
asynchronously from script, but that no longer happens. With this
change, it becomes possible to safely pass nodes to layout from script
-- a cleanup that can happen in a followup change.
This change also makes two fixes that are necessary to get WOFF2 fonts
working:
1. It adds support for loading web fonts from stylesheets included via
@import rules.
2. It ensure that when web fonts are loaded synchronusly they invalidate
the font cache. This led to incorrect font rendering when running
tests before.
Fixes#31598.
Instead of replacing Stylist's device on every reflow, only replace it
when the viewport changes. In addition, preserve the root font size from
the previous reflow fixing an issue where `rem` units were not properly
computed between reflows.
This fixes a bug where fonts that are sized using `rem` units change
size on reload.
This adds basic support for `getClientRects()` by sharing code with the
implementation of `getBoundingClientRect()`. In addition to sharing
code, it also shares all of the bugs. Primarily, scrolilng positions are
not taken into account when return boundary rectangles.
This brings the version of WebRender used in Servo up-to-date with Gecko
upstream. The big change here is that HiDPI is no longer handled via
WebRender. Instead this happens via a scale applied to the root layer in
the compositor. In addition to this change, various changes are made to
Servo to adapt to the new WebRender API.
Co-authored-by: Mukilan Thiyagarajan <mukilan@igalia.com>
The specification gives instructions for how these values should be
propagated. The other big changs here is that they aren't applied to the
`<body>`.
Co-authored-by: Oriol Brufau <obrufau@igalia.com>
Instead of letting Stylo filter `@font-face` rules, handle this
filtering in Servo. It doesn't make sense that Stylo knows about what
fonts Servo supports. This also cleans up a bit the way that this is
handled, giving an entire stylesheet of rules to the font cache to
process instead of letting each layout thread walk the rules. This
brings more of the font-related code into the FontCacheThread itself.
This is the first step toward adding WOFF2 support and fixing various
web font related bugs.
* script: Do not run layout in a thread
Instead of spawning a thread for layout that almost always runs
synchronously with script, simply run layout in the script thread.
This is a resurrection of #28708, taking just the bits that remove the
layout thread. It's a complex change and thus is just a first step
toward cleaning up the interface between script and layout. Messages are
still passed from script to layout via a `process()` method and script
proxies some messages to layout from other threads as well.
Big changes:
1. Layout is created in the script thread on Document load, thus every
live document is guaranteed to have a layout. This isn't completely
hidden in the interface, but we can safely `unwrap()` on a Document's
layout.
2. Layout configuration is abstracted away into a LayoutConfig struct
and the LayoutFactory is a struct passed around by the Constellation.
This is to avoid having to monomorphize the entire script thread
for each layout.
3. Instead of having the Constellation block on the layout thread to
figure out the current epoch and whether there are pending web fonts
loading, updates are sent synchronously to the Constellation when
rendering to a screenshot. This practically only used by the WPT.
A couple tests start to fail, which is probably inevitable since removing
the layout thread has introduced timing changes in "exit after load" and
screenshot behavior.
Co-authored-by: Josh Matthews <josh@joshmatthews.net>
* Update test expectations
* Fix some issues found during review
* Clarify some comments
* Address review comments
---------
Co-authored-by: Josh Matthews <josh@joshmatthews.net>
In order for stylo to be a separate crate, it needs to depend on less
things from Servo. This change makes it so that stylo no longer depends
on servo_url.
This completes the transition to compiling Servo with rust stable. Some
nightly-only features are still used when compiling the `script` and
`crown` crates, as well as for some style unit tests. These will likely
break with newer compiler versions, but `crown` can be disabled for them
conditionally. This is just the first step.
This has some caveats:
1. We need to disable setting up the special linker on Linux. The -Z
option isn't supported with stable rust so using this is out --
meanwhile we can't be sure that lld is installed on most systems.
2. `cargo fmt` still uses some unstable options, so we need to rely on
the unstable toolchain just for running `fmt`. The idea is to fix this
gradually.
* Add initial support for sticky positioning for non-legacy layout
Many tests still fail for a variety of reasons. One of the primary ones
is that CSSOM currently does not return correct values for elements
positioned by sticky nodes. This requires changes to WebRender to work
properly.
* Fix an assertion failure in the legacy layout sticky code
* Sort stacking contexts and stacking containers by painting order
* fix stealing of stacking containers; fix interleaving with fragments
* actually positioned stacking containers should be stolen too
* update expectations and clean up panic changes
* rework naming and docs
* rename s_c_a_p_s_c to real_s_c_a_p_s_c; fix docs
* rename InlineStackingContainer to AtomicInlineStackingContainer
* rework debug logging to use PrintTree
* clean up docs and PrintTree output
* don't panic unless cfg!(debug_assertions) is true
* update expectations
Refactor the scrolling and scrollable area calculation on the window
object, to make it better match the specification. This has some mild
changes to behavior, but in general things work the same as they did
before. This is mainly preparation for properly handling viewport
propagation of the `overflow` property but seems to fix a few issues as
well.
There is one new failure in Layout 2020 regarding `position: sticky`,
but this isn't a big deal because there is no support for `position:
sticky` in Layout 2020 yet.
Co-authored-by: Rakhi Sharma <atbrakhi@igalia.com>
* Upgrade vendored version of WebRender
* Patch WebRender: upgrade version of gleam
* Restore hit testing implementation
* Fix WebRender warnings
* Adapt Servo to new WebRender
* Update results
* Add a workaround for #30313
This slightly expands text boundaries in order to take into account the
fact that layout isn't measuring glyph boundaries.
This also removes the meta viewport support (which was implemented on top), but that also had a single test and is disabled everywhere, so I'm not too concerned, it can be implemented again if / when needed.
When rendering a page containing an iframe, layout 2020
creates parallel 'Layout' threads which share workers
in the stylo thread pool.
Because of the way the 'StyleSharingCache' is designed
using TLS for storage of the LRU cache, this leads to
a double borrow of the cache when both layout threads
run concurrently.
More details about the issue can be found here:
https://gist.github.com/mukilan/ed57eb61b83237a05fbf6360ec5e33b0
This PR is a workaround until we find a more elegant/optimal
design that also can work for gecko. The fix for now is
simply to not allow multiple layouts in parallel.
Signed-off-by: Mukilan Thiyagarajan <me@mukilan.in>
This moves more members to the CompositorDisplayListInfo struct, which
now holds all miscellaneous, non-WebRender data when sending display
lists. It also documents what each things sent with a display list does.
Backport several style changes from Gecko
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This change refactors how layout is done in Layout 2020 in preparation
for a compositor-side scroll tree:
1. Now the SpatialId and ClipId of each fragment is stored separately.
This will allow storing a scroll node id instead of only the handle
to the WebRender spatial node.
2. Separate out stacking context tree construction and display list
building. This change will make it possible to eventually build the
stacking context tree without the full display list if we find that
necessary. For instance, this might be useful to cache containing
block boundaries.
3. Add a `DisplayList` struct that stores both the WebRender display
list builder and the compositor info. This exposes the API to the
layout thread for display list building.
In addition, this change adds a lot of missing documentation. This
should not change behavior.
There are duplicate sets of Layout DOM wrappers: one for Layout 2013 and
one for Layout 2020. As part of cleaning up and simplifying the
wrappers, this change parameterizes them on the specific layout data
they contain. This allows them to be shared again. In addition, various
small cleanups are included.
Fixes#29691.
Script will only scroll if it detects that an element has a scrolling
box, so this change adds an implementation of the scroll area query to
Layout 2020. This allows some scrolling tests to start passing.
This change also updates all expected results in css-backgrounds and
cssom-view.
Scrolling from script should flow layout and send a display list to
WebRender. This allows all of the scroll nodes to exist in WebRender
before asking it to move the node.
See https://gist.github.com/paulirish/5d52fb081b3570c81e3a.
Fixes#29659.
This change adds support for the <iframe> element to Layout 2020. In
addition, certain aspects of the implementation are made the same
between both layout systems.
Store hit testing information in a data structure that sits alongside
the display list in the compositor. This will allow the compositor to
store more information per-node. The data structure also takes care of
de-duplicating information between successive display list entries. In
the future, the data structure can be even more aggressive in producing
smaller side hit testing lists, if necessary.
The Linux kernel imposes a 15-byte limit on thread names[1]. This means
information that does not fit in this limit, e.g., the pipeline ID of
layout and script threads, is lost in a debugger and profiler (see the
first column of the table below).
This commit shortens the thread names used in Servo to maximize the
amount of information conveyed. It also rectifies some inconsistencies
in the names.
| Before | After |
|-------------------|-------------------|
| `BluetoothThread` | `Bluetooth` |
| `CanvasThread` | `Canvas` |
| `display alert d` | `AlertDialog` |
| `FontCacheThread` | `FontCache` |
| `GLPlayerThread` | `GLPlayer` |
| `HTML Parser` | `Parse:www.examp` |
| `LayoutThread Pi` | `Layout(1,1)` |
| `Memory profiler` | `MemoryProfiler` |
| `Memory profiler` | `MemoryProfTimer` |
| `OfflineAudioCon` | `OfflineACResolv` |
| `PullTimelineMar` | `PullTimelineDat` |
| `ScriptThread Pi` | `Script(1,1)` |
| `WebWorker for h` | `WW:www.example.` |
| `ServiceWorker f` | `SW:www.example.` |
| `ServiceWorkerMa` | `SvcWorkerManage` |
| `Time profiler t` | `TimeProfTimer` |
| `Time profiler` | `TimeProfiler` |
| `WebGL thread` | `WebGL` |
| `Choose a device` | `DevicePicker` |
| `Pick a file` | `FilePicker` |
| `Pick files` | `FilePicker` |
[1]: https://stackoverflow.com/questions/5026531/thread-name-longer-than-15-chars
This does not (yet) upgrade ./rust-toolchain
The warnings:
* dead_code "field is never read"
* redundant_semicolons "unnecessary trailing semicolon"
* non_fmt_panic "panic message is not a string literal, this is no longer accepted in Rust 2021"
* unstable_name_collisions "a method with this name may be added to the standard library in the future"
* legacy_derive_helpers "derive helper attribute is used before it is introduced" https://github.com/rust-lang/rust/issues/79202
This will be used in order to hold animations for pseudo elements in the
DocumentAnimationSet. Also no longer store the OpaqueNode in the
animation and transition data structures. This is already part of the
DocumentAnimationSet key.
Instead of recalculating the animation style every tick of an animation,
cache the computed values when animations change. In addition to being
more efficient, this will allow us to return animation rules as property
declarations because we don't need to consult the final style to produce
them.
