This large block of code is repeated nearly verbatim in LibWeb. Move it
to a helper function that both LibIPC and LibWeb can defer to. This will
let us make changes to this method in a singular location going forward.
Note this is a bit of a regression for the MessagePort. It now suffers
from the same performance issue that IPC messages face - we prepend the
meessage size to the message buffer. This degredation is very temporary
though, as a fix is imminent, and this change makes that fix easier.
We cannot port over Optional<FlyString> until the IDL generator supports
passing that through as an argument (as opposed to an Optional<String>).
Change to FlyString where possible, and resolve any fallout as a result.
Instead of implementing stacking context painting order exactly as it
is defined in CSS2.2 "Appendix E. Elaborate description of Stacking
Contexts" we need to account for changes in the latest standards where
a box can establish a stacking context without being positioned, for
example, by having an opacity different from 1.
Fixes https://github.com/SerenityOS/serenity/issues/21137
The JS::Value being passed through is not a bigint, and needs to be
converted using ConvertToInt, as per:
https://webidl.spec.whatwg.org/#es-unsigned-long-long
Furthermore, the IDL definition also specifies that this is associated
with the [EnforceRange] extended attribute.
This makes it actually possible to pass through an autoAllocateChunkSize
to the ReadableStream constructor without it throwing a TypeError.
Using a vector to represent a list of painting commands results in many
reallocations, especially on pages with a lot of content.
This change addresses it by introducing a SegmentedVector, which allows
fast appending by representing a list as a sequence of fixed-size
vectors. Currently, this new data structure supports only the
operations used in RecordingPainter, which are appending and iterating.
This is quite niche, but lets us convert parsing methods to accepting
TokenStream, while still being able to call them when we just have a
lone token. Specifically we'll use this in the next commit, but it's
likely to also be useful as a stop-gap measure when converting more
parsing methods.
Frequently we want to parse "anything that's a `<length-percentage>`" or
similar, which could be a constant value or a calculation, but didn't
have a nice way of doing so. That meant repeating the same "try and
parse a dimension, see if it's the right type, then maybe try and parse
a calculation and see if that's the right type" boilerplate code. Or
more often, forgetting about calculations entirely.
These helpers should make that a lot more convenient to do. And they
also use TokenStream, so we can eventually drop the old `parse_length()`
method.
With this change, we create substantially fewer border painting
commands, which means fewer reallocations of the vector that stores
commands.
This makes the rendering of
https://html.spec.whatwg.org/multipage/browsing-the-web.html visibly
faster, where we allocated ~10 of such commands now vs ~8000 before.
We already have the src attribute stored as a String, so it's completely
wasteful to convert it to a ByteString. We were even doing it twice when
loading each image.
The fix here was to stop using StringBuilder::append(char) when told to
append a code point, and switch to StringBuilder::append_code_point(u32)
There's probably a bunch more issues like this, and we should stop using
append(char) in general since it allows building of garbage strings.
I noticed while debugging a fully downloaded page that it was trying
to preconnect to a file:// host. That doesn't make any sense, so let's
add a tiny bit of logic to ignore preconnect requests for file: and
data: URLs.
With this change, instead of applying scroll offsets during the
recording of the painting command list, we do the following:
1. Collect all boxes with scrollable overflow into a PaintContext,
each with an id and the total amount of scrolling offset accumulated
from ancestor scrollable boxes.
2. During the recording phase assign a corresponding scroll_frame_id to
each command that paints content within a scrollable box.
3. Before executing the recorded commands, translate each command that
has a scroll_frame_id by the accumulated scroll offset.
This approach has following advantages:
- Implementing nested scrollables becomes much simpler, as the
recording phase only requires the correct assignment of the nearest
scrollable's scroll_frame_id, while the accumulated offset from
ancestors is applied subsequently.
- The recording of painting commands is not tied to a specific offset
within scrollable boxes, which means in the future, it will be
possible to update the scrolling offset and repaint without the need
to re-record painting commands.
