The expensive part of creating a segmenter is doing the locale and UCD
data lookups at creation time. Instead of doing this once per text node,
cache the segmenters on the document, and clone them as needed (cloning
is much, much cheaper).
On a profile loading Ladybird's GitHub repo, the following hot methods
changed as follows:
ChunkIterator ctor: 6.08% -> 0.21%
Segmenter factory: 5.86% -> 0%
Segmenter clone: N/A -> 0.09%
Calls to `Document::set_needs_display()` and
`Paintable::set_needs_display()` now invalidate the display list by
default. This behavior can be changed by passing
`InvalidateDisplayList::No` to the function where invalidating the
display list is not necessary.
...if only the scroll offset is updated.
Currently, on any document with a large amount of content, the process
of building a display list is often more expensive than its
rasterization. This is because the amount of work required to build a
display list is proportional to the size of the paintable tree, whereas
rasterization only occurs for the portion visible in the viewport.
This change is the first step toward improving this process by caching
the display list across repaints when neither style nor layout requires
invalidation. This means that repainting while scrolling becomes
significantly less expensive, as we only need to reapply the scroll
offsets to the existing display list.
The performance improvement is especially visible on pages like
https://ziglang.org/documentation/master/ or
https://www.w3.org/TR/css-grid-2/
For the SVG <use> element, we want to support loading HTML documents
that have a SVG element inside of it pointed to by the URL fragment.
In this situation we would need to fetch and parse the entire document
in SharedImageRequest (so that we can still cache the SVGs). Rename
SharedImageRequest to SharedResourceRequest to make the class a little
more generic for future usecases.
To avoid expensive lookups, we now cache a weak pointer from document to
the last known node navigable. Before using the cache, we validate that
the document is still the navigable's active document.
Navigables are re-used for navigations within the same tab. Its current
ownership of the cursor position is a bit ad-hoc, so nothing in the spec
indicates when to reset the cursor, nor do we manually do so. So when a
cursor update happens on one page, that cursor is retained on the next
page.
Instead, let's have the document own the cursor. Each navigation results
in a new document, thus we don't need to worry about resetting cursors.
This also makes many of the callsites feel nicer. We were previously
often going from the node, to the document, to the navigable, to the
cursor. This patch removes the navigable hop.
We explicitly stopped visting the map of documents to console clients in
commit 44659f2f2a to avoid keeping the
document alive. However, if nothing else visits the console clients, we
may set the top-level console client to a client that has been garbage
collected.
So instead of storing this map, just store the console client on the
document itself. This will allow the document to visit its client.
We were mistakenly executing the current node's script instead of the
document's pending parsing-blocking script.
This caused ~1000 WPT tests to time out, since we never ended up firing
a load event for XHTML pages that load multiple external scripts.
The first time Document learns its viewport size, we now suppress firing
of the resize event.
This fixes an issue on multiple websites that were not expecting resize
events to fire so early in the loading process.
The DocumentTimeline constructor used the current millisecond time to
initialize its currentTime, but that means that a newly created timeline
would always have a different time value than other timelines that have
been through the update_animations_and_send_events function.
This allows searching for text with case-insensitivity. As this is
probably what most users expect, the default behavior is changes to
perform case-insensitive lookups. Chromes may add UI to change the
behavior as they see fit.
This allows the browser to send a query to the WebContent process,
which will search the page for the given string and highlight any
occurrences of that string.
Although refreshing is cheap, it was performed before each hit-testing
and was 2-4% in profiles on Discord and Twitter.
Now clip and scroll states are refreshed only if scroll offset has
changed.
This patch fixes two issues:
- Animation events that should go to the target element now do
(some were previously being dispatched on the animation itself.)
- We update the "previous phase" and "previous iteration" fields of
animation effects, so that we can actually detect phase changes.
This means we stop thinking animations always just started,
something that caused each animation to send 60 animationstart
events every second (to the wrong target!)
We were inadvertently keeping all documents alive by installing a
console client for them. This patch fixes the issue by adding a
finalizer to Document, and having that be the way we detach console
clients. This breaks the cycle.
With this change, we can spam set .innerHTML in a loop and memory
usage remains stable.
Fixes#14612
Changes the signature of queue_global_task() from AK:Function to
JS::HeapFunction to be more clear to the user of the function that this
is what it uses internally.
This change adds the `clear()`, `captureEvents()` and `releaseEvents()`
methods to the document object. These methods are obsolete, but are
still included in the HTML specification, which says they must do
nothing.
These changes do not solve hanging `location.reload()` and
`location.go()` but only align implementation with the latest edits in
the specification.
`WindowProxy-Get-after-detaching-from-browsing-context` test output is
affected because `iframe.remove();` no longer synchronously does
destruction of a document, but queues a task on event loop.
Co-Authored-By: Andrew Kaster <akaster@serenityos.org>
Implements the "top layer" concept from "CSS Positioned Layout Module
Level 4" specification.
- The tree builder is modified to ensure that layout nodes created by
top layer elements are children of the viewport.
- Implements missing steps in `showModal()` to add an element top top
layer.
- Implements missing steps in `close()` to remove an element from top
layer.
Further steps could be:
- Add support for `::backdrop` pseudo-element.
- Implement the "inert" concept from HTML spec to block hit-testing
when element from top layer is displayed.
