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).
"TPGD" is short for "Typical Prediction for Generic Direct coding",
and the "ON" bit turns it on. In this mode, before decoding a line,
we decode a single bit first that controls if the current line is
just a copy of the previous line. If so, the line's pixels aren't
encoded, the decoder just copies the previous line.
I created this by running
jbig2 -i Tests/LibGfx/test-inputs/bmp/bitmap -f bmp \
-o bitmap -F jb2 -ini tpgdon.ini
where tpgdon.ini contained:
-Gen -Seg 1
-Gen -Param -TpGDon 1
See previous commits in this directory for details on the `jbig2` tool.
Sadly, the TPGDON writing path in `jbig2` wasn't implemented yet,
so I had to add this. See the PR that added this commit for my
local diff to `jbig2`.
I'm somewhat confident that my change to `jbig2` (and hence the
image added in this commit) is correct because:
1. `jbig2` succeeds in converting this file to a bmp file,
while it failed without my patch (the decoding codepath in
`jbig2` does have TPGDON support)
2. Other pdf viewers display the output of
`Meta/jbig2_to_pdf.py -o foo.pdf path/to/bitmap-tpgdon.jbig2 399 400`
the same way we do
Most image viewers can't display JBIG2 files.
All PDF viewers can display JBIG2 files.
This is useful for checking that PDF viewers render JBIG2 files the
same way we do.
