Remove concept of Layers from Servo
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Layers were a feature of the legacy drawing path. If we re-add them at
some point, it probably makes more sense to make them a product of
display list inspection.
This change also remove a bunch of dead painting code.
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Layers were a feature of the legacy drawing path. If we re-add them at
some point, it probably makes more sense to make them a product of
display list inspection.
This change also remove a bunch of dead painting code.
This removes paint threads, rust-layers dependency, and changes
optional webrender types to be required.
The use_webrender option has been removed, however I've left
the "-w" command line option in place so that wpt
runner can continue to pass that. Once it's removed from there
we can also remove the -w option.
Once this stage is complete, it should be fine to change the
display list building code to generate webrender display
lists directly and avoid the conversion step.
We needed a separate thread in the chrome process because communication to the
compositor is done through a trait object, and cross-process virtual calls are
forbidden.
Also, the fact that these messages are ultimately handled by the compositor is
an implementation detail; conceptually, the relevant constellation is supposed
to handle these messages.
So instead, the script thread will now send the messages to the constellation,
which will ask the compositor to handle them.
Don't block the script listener thread on window.close().
Thank you for contributing to Servo! Please replace each `[ ]` by `[X]` when the step is complete, and replace `__` with appropriate data:
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Either:
- [ ] There are tests for these changes OR
- [x] These changes do not require tests because no tangible effect
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This does not appear to have any effect. I believe this has been the case
since e841065351, when the helper thread was
introduced.
It was added in a7ef1cd35e, where it blocked the
script thread rather than this helper thread.
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This does not appear to have any effect. I believe this has been the case
since e841065351, when the helper thread was
introduced.
It was added in a7ef1cd35e, where it blocked the
script thread rather than this helper thread.
Add new compositor message to get scroll_offset;
Add new layout query for computed value of overflow-x/y;
Implement layer_id method for ThreadSafeLayoutNode;
Add new layout query for layer_id;
Implement script interface for getting scrollTop and scrollLeft, as well as relavant helper functions.
This changes headless operation to strictly be a runtime option, rather
than a compile-time one. Note that the old headless version still relied
on a display server to support WebGL, while it now requires one all the
time.
Fixes#8573
has loaded.
This avoids a flash of unstyled content, which looks especially bad in
browser.html since unstyled content is white and browser.html has a
transparent background.
Closes#9996.
Instead, schedule a delayed composite after each frame of an animation.
The previous code would cause jank, because the following sequence
frequently occurred:
1. The page uses `requestAnimationFrame()` to request a frame.
2. The compositor receives the message, schedules a composite,
dispatches the rAF message to the script thread, composites, and goes to
sleep waiting for vblank (frame 1).
3. The script makes a change and sends it through the pipeline.
Eventually it gets painted and is sent to the compositor, but the
compositor is sleeping.
4. The compositor wakes up, sees the new painted content, page flips,
and goes to sleep (frame 2). Repeat from step 1.
The problem is that we have two composition frames, not just one. This
halves Web apps' framerate!
This commit fixes the problem by scheduling the composite in step 2 to
12 ms in the future. We already have this delayed-composition
functionality in the form of the scrolling timer, which I repurposed and
renamed to the "delayed composition timer" for this task. This change
gives the page 12 ms to prepare the frame, which seems to usually be
enough, especially with WebRender.
Note that simply removing the scheduled composite after rAF is not the
correct solution. If this is done, then pages that call rAF and don't
modify the page won't receive future rAFs, since the compositor will be
sleeping and won't be notified of vblank.
Fixes a bunch of jank in browser.html. The remaining jank seems to be a
problem with browser.html itself.
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!
