Sticky positioning is implemented by modifying the algorithm for
assigning and refreshing scroll frames. Now, elements with
"position: sticky" are assigned their own scroll frame, and their
position is refreshed independently from regular scroll boxes.
Refreshing the scroll offsets for sticky boxes does not require display
list invalidation.
A separate hash map is used for the scroll frames of sticky boxes. This
is necessary because a single paintable box can have two scroll frames
if it 1) has "position: sticky" and 2) contains scrollable overflow.
For a long time, we've used two terms, inconsistently:
- "Identifier" is a spec term, but refers to a sequence of alphanumeric
characters, which may or may not be a keyword. (Keywords are a
subset of all identifiers.)
- "ValueID" is entirely non-spec, and is directly called a "keyword" in
the CSS specs.
So to avoid confusion as much as possible, let's align with the spec
terminology. I've attempted to change variable names as well, but
obviously we use Keywords in a lot of places in LibWeb and so I may
have missed some.
One exception is that I've not renamed "valid-identifiers" in
Properties.json... I'd like to combine that and the "valid-types" array
together eventually, so there's no benefit to doing an extra rename
now.
These control the state of CSS counters.
Parsing code for `reversed(counter-name)` is implemented, but disabled
for now until we are able to resolve values for those.
This seems to have been required when pseudo-elements were first
implemented, but has since become unused. It's also awkward because we
don't have access to the DOM Element and its CountersSet at this point.
So, let's remove it.
For reference, Chrome&Firefox both return the computed value for
`content: counter(foo)` as `counter(foo)`, not as the computed string.
So not computing it here seems like the intended behaviour.
When both insets in a given axis are auto, we should use the static
position for absolutely positioned elements.
By doing this correctly, we exposed a bunch of other small bugs which
had to be fixed to compensate for new test failures. Those fixes are
included here as well:
- Don't apply margins twice.
- Compute the static position containing block chain correctly.
This makes https://brave.com/ look much better. :^)
A bunch of this is leftover from pre porting over to new AK::String.
For example, for functions which previously took a ByteString const&
now accepting a StringView.
This allows positioning a child SVG relative to its parent SVG.
Note: These have been implemented as CSS properties as in SVG 2, these
are geometry properties that can be used in CSS (see
https://www.w3.org/TR/SVG/geometry.html), but there is not much browser
support for this. It is nicer to implement than the ad-hoc SVG
attribute parsing though, so I feel it may make sense to port the rest
of the attributes specified here (which should fix some issues with
viewport relative sizes).
This makes them cheap to move around, since we can store them in a
NonnullOwnPtr instead of memcopying 2584(!) bytes.
Drastically reduces the chance of stack overflow while building the
layout tree for deeply nested DOMs (since tree building was putting
these things on the stack).
This change also exposed a completely unnecessary ComputedValues deep
copy in block layout.
The paintable tree structure more closely matches the painting order
when fragments are owned by corresponding inline paintables. This
change does not affect the layout tree, as it is more convenient for
layout purposes to have all fragments owned by a block container in
one place.
Additionally, this improves performance significantly on pages with
many fragments, as we no longer have to walk the ancestor chain up
to the closest block container to determine if a fragment belongs
to an inline paintable.
This patch makes a few changes to the way we calculate line-height:
- `line-height: normal` is now resolved using metrics from the used
font (specifically, round(A + D + lineGap)).
- `line-height: calc(...)` is now resolved at style compute time.
- `line-height` values are now absolutized at style compute time.
As a consequence of the above, we no longer need to walk the DOM
ancestor chain looking for line-heights during style computation.
Instead, values are inherited, resolved and absolutized locally.
This is not only much faster, but also makes our line-height metrics
match those of other engines like Gecko and Blink.
- We now propagate changes in font and line-height to anonymous wrappers
when doing a partial style update after invalidation.
- We no longer (incorrectly) propagate style from table wrapper boxes
to the table root, since inheritance works in the other direction.
Fixes#22395
This commit un-deprecates DeprecatedString, and repurposes it as a byte
string.
As the null state has already been removed, there are no other
particularly hairy blockers in repurposing this type as a byte string
(what it _really_ is).
This commit is auto-generated:
$ xs=$(ack -l \bDeprecatedString\b\|deprecated_string AK Userland \
Meta Ports Ladybird Tests Kernel)
$ perl -pie 's/\bDeprecatedString\b/ByteString/g;
s/deprecated_string/byte_string/g' $xs
$ clang-format --style=file -i \
$(git diff --name-only | grep \.cpp\|\.h)
$ gn format $(git ls-files '*.gn' '*.gni')
According to the CSS font matching algorithm specification, it is
supposed to be executed for each glyph instead of each text run, as is
currently done. This change partially implements this by having the
font matching algorithm produce a list of fonts against which each
glyph will be tested to find its suitable font.
Now, it becomes possible to have per-glyph fallback fonts: if the
needed glyph is not present in a font, we can check the subsequent
fonts in the list.
The postitioning enum values are used by the position CSS property.
Unfortunately, the prior naming clashes with the CSS Values-4 type
named position, which will be implemented in a later commit.
Instead of resolving lengths used in the backdrop-filter during
painting, we can do that earlier in apply_style().
This change moves us a bit closer to the point when the stacking
context tree will be completely separated from the layout tree :)
Renaming the DeprecatedString version of this function to
Element::get_deprecated_attribute.
While performing this rename, port over functions where it is trivial to
do so to the Optional<String> version of this function.
This makes multiple levels of quote actually use different quotation
marks, instead of always the first available pair of them.
Each Layout::Node remembers what the quote-nesting level was before its
content was evaluated, so that we can re-use this number in
`apply_style()`. This is a bit hacky, since we end up converting the
`content` value into a string twice.
`StyleProperties::content()` now takes an initial quote-nesting level,
and returns the final level after that content.
ImageStyleValue has a visit_edges() method, although it is not a
GC-allocated object. This is necessary because it owns a GC-allocated
ImageRequest that we want to visit, instead of using JS::Handle, to
avoid leaks. In the future, we might want to make StyleValue be
GC-allocated.
For now, this change adds missing visit_edges() calls for objects that
own ImageStyleValue.
This fixes an issue where the value would be out of sync with reality
in anonymous wrapper block boxes, since we forgot to compute m_visible
after assigning the computed values to them.
Fixes#21106
