This refactor is preparation for implementing a specification
compliant transitions and animations processing model.
These data structures hold all the animation information about a single
node. Since adding, updating, and modifying animations for a single node
are all interdependent, it makes sense to start encapsulating animation
data and functionality into a single data structure. This also opens up
the possibility for easier concurrency in the future by more easily
allowing per-node mutexes.
Add support for canceling CSS transitions
This change adds support for canceling CSS transitions when a property is
no longer transitionable. Support for canceling and replacing CSS
transitions when the end value changes is still pending. This change
also takes advantage of updating the constellation message to fix a bug
where transition events could be sent for closed pipelines.
Fixes#15079.
<!-- Please describe your changes on the following line: -->
---
<!-- Thank you for contributing to Servo! Please replace each `[ ]` by `[X]` when the step is complete, and replace `___` with appropriate data: -->
- [x] `./mach build -d` does not report any errors
- [x] `./mach test-tidy` does not report any errors
- [x] These changes fix#15079.
<!-- Either: -->
- [x] There are tests for these changes OR
- [ ] These changes do not require tests because ___
<!-- Also, please make sure that "Allow edits from maintainers" checkbox is checked, so that we can help you if you get stuck somewhere along the way.-->
<!-- Pull requests that do not address these steps are welcome, but they will require additional verification as part of the review process. -->
This change adds support for canceling CSS transitions when a property
is no longer transitionable or when an element becomes styled with
display:none. Support for canceling and replacing CSS transitions when
the end value changes is still pending. This change also takes advantage
of updating the constellation message to fix a bug where transition
events could be sent for closed pipelines.
Fixes#15079.
RuleTree::gc is now a safe method that any thread can call
at any time, and StrongRuleNode values can all be dropped
whenever their owner want to, on any thread.
There is no need to set the dirty descendants flag unsafely from the layout side
for elements with pending restyles, we can do that on the DOM side when draining
the restyles from the Document.
For clarity, I introduce <LayoutDom<Element>>::parent_node_ref to contain
the remaining unsafety bits out of composed_parent_node_ref which is more
complex than just a field access.
They don't do anything fancy so there is no additional unsafety calling them
compared to using LayoutDom in the first place, the usual story of all
those changes.
This safe method is the basic block to access element attributes from layout.
We reuse it in the other attr-related layout methods to remove a pretty big
source of rampant unsafe code between script and layout.
Layout viewer for layout 2020
- [X] `./mach build -d` does not report any errors
- [X] `./mach test-tidy` does not report any errors
This PR makes layout 2020 dump the box and fragment tree states into json files that can be visualized with the layout viewer tool. This tool has not much functionality other than displaying these trees and allowing to inspect each node additional data, so there is a lot of room for improvements. Some ideas for follow-ups:
- Make the tool create and display diffs between tree states.
- Actually allow creating new debug scopes during box tree and fragment tree construction. Right now there is a single scope created after constructing both trees, which is not ideal as it only allows looking at the reflow result.
- Right now an independent JSON file is created per reflow. It would be nice to unify the data obtained on each reflow on a single JSON, so diffs between reflows can be displayed as well.
- Dump and display the DOM tree. Link boxes to DOM nodes.
- #23339
This query is used to get the clientTop, clientWidth, clientHeight,
clientLeft properties of DOM objects. "NodeGeometry" doesn't really
capture what these properties do as they often are returning the width
of element border.
This isn't correct yet, but it is necessary to give a value in order for
scrolling from script to work. Later this should give an accurate
content box response as well as work for non-root elements.
