This value is at most 46, so a u8 is enough.
We have tens of thousands of these contexts.
(We could pack the is_mps bit into that u8 as well, but
then the I() and MPS() functions need to return helper objects
instead of a direct reference, so let's not do that part for now.)
If a lossless webp has 3 or 4 colors, it uses 2 bits per pixel to
store an offset into a "color index" (which the spec explicitly does
not call palette since it says the 'color cache' is more like that).
This way, it can pack 4 pixels into a single pixel.
If the width of the output image wasn't evenly divisble by 4,
we used to write out-of-bounds in the last few columns of each
row, since we used to always write all 4 pixels.
Found by clusterfuzz. Probably fixes
https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=66082
While here, spruce up the comments very slightly.
If an unexpected token is encountered when parsing an SVG attribute it
is now immediately propagated with ErrorOr. Previously, some situations
where an unexpected token was encountered could cause a crash.
If `Document::resolve()` was called during parsing, it'd change the
reader's current position, so the parsing code that called it would
then end up at an unexpected position in the file.
Parser.cpp already had special-case recovery when a stream's length
was stored in an indirect reference.
Commit ead02da98ac70c ("/JBIG2Globals") in #23503 added another case
where we could resolve indirect reference during parsing, but wasn't
aware of having to save and restore the reader position for that.
Put the save/restore code in `DocumentParser::parse_object_with_index`
instead, right before the place that ultimately changes the reader's
position during `Document::resolve`. This fixes `/JBIG2Globals` and
lets us remove the special-case code for `/Length` handling.
Since this is kind of subtle, include a test.
This test uses a JBIG2Globals with an indirect reference,
and contains an indirect reference for a stream length.
When we parse the main JBIG2 image's stream, we unfilter
its data, which causes these two indirect references to
be resolved during parsing.
I started with the output of
Meta/jbig2_to_pdf.py -o foo.pdf \
Tests/LibGfx/test-inputs/jbig2/bitmap.jbig2
and then manually added a
/DecodeParms <</JBIG2Globals 6 0 R>>
entry pointing to an empty stream, and made that new stream
object's length an indirect reference too for good measure.
I used `mutool clean` to fix up offsets a bit. But that also
removes the indirect reference for a stream's length, so I
manually put that back in and adjusted the offset to the last
object in the xref table and the startxref value.
Use the new DOM tree version mechanism to allow HTMLCollection to
remember its internal list of elements instead of rebuilding it on
every access.
This avoids thousands of full DOM walks while loading our GitHub repo.
~15% speed-up on jQuery subtests in Speedometer 3.0 :^)
This patch adds a u64 version counter to DOM::Document that increments
whenever the tree structure changes (via node insertion or removal),
or an element attribute is changed somehow.
This will be used as a crude invalidation mechanism for HTMLCollection
to cache its elements.
- Compare only the animated properties
- Clone only the hash map containing animated properties, instead of
the entire StyleProperties.
Reduces `KeyframeEffect::update_style_properties()` from 10% to 3% in
GitHub profiles.
Non-recursive pseudo classes are easy to evaluate, so let's allow them
on the fast path.
Increases fast path coverage when loading our GitHub repo from 48% to
56% of all selectors evaluated.
If we determine that a selector is simple enough, we now run it using a
special matching loop that traverses up the DOM ancestor chain without
recursion.
The criteria for this fast path are:
- All combinators involved must be either descendant or child.
- Only tag name, class, ID and attribute selectors allowed.
It's definitely possible to increase the coverage of this fast path,
but this first version already provides a substantial reduction in time
spent evaluating selectors.
48% of the selectors evaluated when loading our GitHub repo are now
using this fast path.
18% speed-up on the "Descendant and child combinators" subtest of
StyleBench. :^)
This is much more useful than the previous format, as you can now just
paste the path into a site like https://svg-path-visualizer.netlify.app/
to debug issues.
These two options are additions of the PDF specification. They are valid
for both 1D and 2D, but let's bail out if we encounter them in a 2D
image, as we don't have a test case yet.
There is no need to run full table layout if we are only interested in
calculating its width.
This change reduces compute_table_box_width_inside_table_wrapper()
from ~30% to ~15% in profiles of "File changed" pages on github.
This URL library ends up being a relatively fundamental base library of
the system, as LibCore depends on LibURL.
This change has two main benefits:
* Moving AK back more towards being an agnostic library that can
be used between the kernel and userspace. URL has never really fit
that description - and is not used in the kernel.
* URL _should_ depend on LibUnicode, as it needs punnycode support.
However, it's not really possible to do this inside of AK as it can't
depend on any external library. This change brings us a little closer
to being able to do that, but unfortunately we aren't there quite
yet, as the code generators depend on LibCore.
Instead of wrapping every entry in Optional, use the null state of the
style pointer for the same purpose.
This shrinks StyleProperties by 1752 bytes per instance.
Instead of a gigantic array with space for every possible CSS property
being animated at the same time.
This shrinks StyleProperties by 3480 bytes per instance.
Instead of TextPaintable fragments being an offset+length view into the
layout node, they are now a view into the paintable instead.
This removes an awkward time window where we'd have bogus state in text
fragments after layout invalidation but before relayout. It also makes
the code slightly nicer in general, since there's less mixing of layout
and painting concepts.
Instead, just rely on the invalidation and lazy relayout that happens as
a consequence of mutating the DOM.
This allows multiple keystrokes to coalesce into a single relayout if
necessary, dramatically improving performance when typing text into
form fields on complex pages.
Before this change, we were not detaching paintables from DOM nodes
within shadow subtrees.
This appears to be the main reason that keyboard editing was doing
immediate forced relayout: doing a full layout invalidation meant we'd
build a new layout tree, which then hid the problem with with
still-attached paintables.
By detaching them before committing a new layout, we make it possible
for keyboard editing to just use normal relayout, instead of full forced
invalidation & relayout.
CharacterData nodes and their subclasses (most commonly Text) don't have
style, as style is specific to Elements. So there's no need to mark them
for a style update when their content is programmatically changed.
Previously, we returned from the value setter if the specified value
was above the max value. This is not required, as the getter clamps the
returned value to the max value.
Rather than make path segments virtual and refcounted let's store
`Gfx::Path`s as a list of `FloatPoints` and a separate list of commands.
This reduces the size of paths, for example, a `MoveTo` goes from 24
bytes to 9 bytes (one point + a single byte command), and removes a
layer of indirection when accessing segments. A nice little bonus is
transforming a path can now be done by applying the transform to all
points in the path (without looking at the commands).
Alongside this there's been a few minor API changes:
- `path.segments()` has been removed
* All current uses could be replaced by a new `path.is_empty()` API
* There's also now an iterator for looping over `Gfx::Path` segments
- `path.add_path(other_path)` has been removed
* This was a duplicate of `path.append_path(other_path)`
- `path.ensure_subpath(point)` has been removed
* Had one use and is equivalent to an `is_empty()` check + `move_to()`
- `path.close()` and `path.close_all_subpaths()` assume an implicit
`moveto 0,0` if there's no `moveto` at the start of a path (for
consistency with `path.segmentize_path()`).
Only the last point could change behaviour (though in LibWeb/SVGs all
paths start with a `moveto` as per the spec, it's only possible to
construct a path without a starting `moveto` via LibGfx APIs).
