Many times, attribute mutation doesn't necessitate a full style
invalidation on the element. However, the conditions are pretty
elaborate, so this first version has a lot of false positives.
We only need to invalidate style when any of these things apply:
1. The change may affect the match state of a selector somewhere.
2. The change may affect presentational hints applied to the element.
For (1) in this first version, we have a fixed list of attribute names
that may affect selectors. We also collect all names referenced by
attribute selectors anywhere in the document.
For (2), we add a new Element::is_presentational_hint() virtual that
tells us whether a given attribute name is a presentational hint.
This drastically reduces style work on many websites. As an example,
https://cnn.com/ is once again browseable.
When the `style` attribute changes, we only need to update style on the
element itself (unless there are [style] attribute selectors somewhere).
Descendants of the element don't need a full style update, a simple
inheritance propagation is enough.
We can now mark an element as needing an "inherited style update" rather
than a full "style update". This effectively means that the next style
update will visit the element and pull all of its inherited properties
from the relevant ancestor element.
This is now used for descendants of elements with animated style.
This required multiple changes:
- Make hashes non-copiable because they contain a heap allocated pointer
- Reference classes via `NonnullOwnPtr` only (they are non-copiable)
- Drop all existing hashes implementations
- Use the `OpenSSLHashFunction` base class to implement the same hashes
I was not able to come up with a way to divide this commit into multiple
without increasing the amount of changes.
Nothing breaks with this commit!
The previous VERIFY statement incorrectly asserted that the
interception state was not "committed" or "scrolled". Updated
the condition to ensure the interception state is either
"committed" or "scrolled" as intended.
Before this change, StyleComputer would essentially take a DOM element,
find all the CSS rules that apply to it, and resolve the computed value
for each CSS property for that element.
This worked great, but it meant we had to do all the work of selector
matching and cascading every time.
To enable new optimizations, this change introduces a break in the
middle of this process where we've produced a "CascadedProperties".
This object contains the result of the cascade, before we've begun
turning cascaded values into computed values.
The cascaded properties are now stored with each element, which will
later allow us to do partial updates without re-running the full
StyleComputer machine. This will be particularly valuable for
re-implementing CSS inheritance, which is extremely heavy today.
Note that CSS animations and CSS transitions operate entirely on the
computed values, even though the cascade order would have you believe
they happen earlier. I'm not confident we have the right architecture
for this, but that's a separate issue.
This improves the quality of our font rendering, especially when
animations are involved. Relevant changes:
* Skia fonts have their subpixel flag set, which means that individual
glyphs are rendered at subpixel offsets causing glyph runs as a
whole to look better.
* Fragment offsets are no longer rounded to whole device pixels, and
instead the floating point offset is kept. This allows us to pass
through the floating point baseline position all the way to the Skia
calls, which already expected that to be a float position.
The `scrollable-contains-table.html` ref test needed different table
headings since they would slightly inflate the column size in the test
file, but not the reference.
Previously this was proxying the call through javascript, which lead to
unexpected crashes when functions returned things that js-api did not
like.
This commit also adds in the spec comments and fixes a few inaccuracies
that were present in the process.
The spec doesn't say they should exist, so we should not
`VERIFY_NOT_REACHED()` when they don't. Prevents a crash in the WPT
`editing/event.html` tests.
The algorithm referenced to in the Editing spec whenever they talk about
obtaining the "resolved" style or value is actually implemented in
ResolvedCSSStyleDeclaration, so use that instead of going directly to
the computed styles.
We were using the anchor_node() as the boundary point node when
collapsing a selection, but the spec tells us to use the start and end
boundary point nodes.
When we originally implemented calc(), the result of a calculation was
guaranteed to be a single CSS type like a Length or Angle. However, CSS
Values 4 now allows more complex type arithmetic, which is represented
by the CSSNumericType class. Using that directly makes us more correct,
and allows us to remove a large amount of now ad-hoc code.
Unfortunately this is a large commit but the changes it makes are
interconnected enough that doing one at a time causes test
regressions.
In no particular order:
- Update our "determine the type of a calculation" code to match the
newest spec, which sets percent hints in a couple more cases. (One of
these we're skipping for now, I think it fails because of the FIXMEs
in CSSNumericType::matches_foo().)
- Make the generated math-function-parsing code aware of the difference
between arguments being the same type, and being "consistent" types,
for each function. Otherwise those extra percent hints would cause
them to fail validation incorrectly.
- Use the CSSNumericType as the type for the CalculationResult.
- Calculate and assign each math function's type in its constructor,
instead of calculating it repeatedly on-demand.
The `CalculationNode::resolved_type()` method is now entirely unused and
has been removed.
Took the opportunity to pull out a helper function for
entry_with_value_1_while_all_others_are_0(), too.
A couple of these require us to have extra contextual information about
what type percentages should resolve to. Until we have that available,
these are left as FIXMEs with a rough approximation.
This reverts commit 76daba3069.
We're going to need separate types for the JS-exposed style values, so
it doesn't make sense for us to match their names with our internal
types.
By doing that we eliminate the need for the vertical flip flag.
As a side effect it fixes the bug when doing:
`canvasContext2d.drawImage(canvasWithWebGLContext, 0, 0);`
produced a flipped image because we didn't account for different origin
while serializing PaintingSurface into Gfx::Bitmap.
Visual progress on https://ciechanow.ski/curves-and-surfaces/
start_loading_next_url() is a no-op if there's a pending resource load,
but not if that resource load has successfully loaded already. There is
a delay between the font resource loading, and it being processed into
a vector font. Calling font_with_point_size() in that gap would
previously erase the previously-loaded font, if the font had multiple
URLs to choose from.
This fixes the icon font on mods.factorio.com :^)
