The tricky bit of this is resolving cycles in extending rules and
ensuring that counter styles are registered in the required order for
extension (i.e. for any pair of extended/extending rules the extended
one should be registered first).
Many CSS grammars call for us to parse `Foo || Bar` but we don't have a
good way to represent this unless we have a custom style value. Usually
we store the values in a `StyleValueList` but since that can only store
non-null elements we have to manually recheck which elements we have at
which index whenever we use it.
This style value holds a Vector of `RefPtr<StyleValue const>` so that we
can represent null values and know what values are at what index without
manually rechecking.
These were moved in 0f04c6d but the namespace remained the same. We also
now forward declare these in `AK/Forward.h` rather than
`LibWeb/Forward.h` (or not at all in the case of `ValueComparingRefPtr`)
Two related problems exist in the current display list architecture:
1. DrawPaintingSurface thread safety: CanvasPaintable::paint() records
the *same* PaintingSurface that the canvas rendering context draws
to. The rendering thread later reads from it, but the main thread
may be concurrently drawing — a data race.
2. Video frames force display list rebuilds: each new video frame
triggers set_needs_display() → full display list rebuild.
Both stem from display list commands holding direct references to
content (surface/bitmap) rather than going through an indirection
layer.
ExternalContentSource is a thread-safe, atomically-refcounted
container that holds an ImmutableBitmap snapshot. The accompanying
DrawExternalContent display list command reads from it during replay,
so producers can swap in new content without rebuilding the list.
Subsequent commits migrate canvas, video, and SVG painting to
ExternalContentSource and then remove DrawPaintingSurface.
This means we don't need to include `FilterValueListStyleValue.h` in as
many places - reducing the rebuild from editing that file from 717 files
to 19.
Replace per-element OrderedHashMap storage for custom properties with
a RefCounted chain (CustomPropertyData) that enables structural
sharing. Each chain node stores only the properties declared directly
on its element, with a parent pointer to the inherited chain.
Elements that don't override any custom properties share the parent's
data directly (just a RefPtr copy). During cascade, only entries that
actually differ from the parent are stored in own_values - the rest
are inherited through the chain. During var() resolution, resolved
values are compared against the parent's and matching entries are
dropped, enabling further sharing.
The chain uses a depth limit (max 32) with flattening, plus
absorption of small parent nodes (threshold 8) to keep lookups fast.
This reduces custom property memory from ~79 MB to ~5.7 MB on
cloudflare.com.
Previously we parsed it as `<custom-ident>` in `<counter>` and as a
keyword in `list-style-type`.
The practical effect of this is:
- Spec defined counter style names in `<counter>` are ASCII lowercased
on parse.
- Non spec defined counter style names are allowed in `list-style-type.
We are still to parse the `symbols()` function but this gives us a
better base for that.
Remove includes from Node.h that are only needed for forward
declarations (AccessibilityTreeNode.h, XMLSerializer.h,
JsonObjectSerializer.h). Extract StyleInvalidationReason and
FragmentSerializationMode enums into standalone lightweight
headers so downstream headers (CSSStyleSheet.h, CSSStyleProperties.h,
HTMLParser.h) can include just the enum they need instead of all of
Node.h. Replace Node.h with forward declarations in headers that only
use Node by pointer/reference.
This breaks the circular dependency between Node.h and
AccessibilityTreeNode.h, reducing AccessibilityTreeNode.h's
recompilation footprint from ~1399 to ~25 files.
Remove 11 heavy includes from Document.h that were only needed for
pointer/reference types (already forward-declared in Forward.h), and
extract the nested ViewportClient interface to a standalone header.
This reduces Document.h's recompilation cascade from ~1228 files to
~717 files (42% reduction). Headers like BrowsingContext.h that were
previously transitively included see even larger improvements (from
~1228 down to ~73 dependents).
When the mouse is dragged from inside a scrollable container to outside
of it, we now automatically scroll the container so the selection can be
extended. Scroll speed scales with the distance past the scrollport
edge, capped at a maximum. Edges close to the viewport boundary get a
wider activation zone so the speed ramp works predictably even when the
mouse has limited room to move.
The logic is encapsulated in AutoScrollHandler, which EventHandler
creates lazily on mouse selection start.
Replace the direct #include of StyleInvalidation.h in Element.h with a
forward declaration in Forward.h. Element.h only uses the type in
function declarations, so the complete type is not needed.
This reduces the recompilation impact of modifying StyleInvalidation.h
from ~1380 files to ~4 files, since Element.h is transitively included
by nearly every HTML and SVG element header.
Previously, any SVG geometry attribute change would mark the entire
document layout tree as dirty, triggering a full layout pass even though
only the SVG subtree was affected. This made SVG geometry animations
unnecessarily expensive.
Fix this by stopping `needs_layout_update` propagation at the SVGSVGBox
boundary and tracking dirty SVG roots separately on the Document. When
`update_layout()` finds that only SVG roots need relayout (and the
document layout root is clean), it runs SVGFormattingContext on each
dirty SVG root in a fresh LayoutState and commits the results directly,
bypassing the full document layout pass entirely.
This results in a substantial performance improvement on pages with
animated SVGs, such as https://www.cloudflare.com/,
https://www.duolingo.com/, and our GC graph explorer page.
This change introduces SlotRegistry to track slot elements per shadow
root. This allows us to iterate slots directly when assigning
slottables for a tree instead of walking an entire subtree.
Previously we implemented an all encompassing `MathDepthStyleValue`
specifically for the `math-depth` property, this was unnecessary since
we can represent `auto-add` and `<integer>` using existing `StyleValue`
classes.
This brings the values created from parsing in line with those set via
`StylePropertyMap` which allows us to simplify computation
Add ElementResizeAction to Page (maybe there's a better place). It's
just a mousemove delegate that updates styles on the target element.
Add ChromeMetrics for zoom-invariant chrome like scrollbar thumb
thickness, resize gripper size, paddings, etc. It's not user-stylable
but separates basic concerns in a way that a visually gifted
designer unlike myself can adjust to taste.
These values are pre-divided by zoom factor so that PaintableBox can
continue using device_pixels_per_css_pixel calls as normal.
The adjusted metrics are computed on demand from Page multiple times
per paint cycle, which is not ideal but avoids lifetime management and
atomics. Maybe someone with more surety about the painting flow control
can improve this, but it won't be a huge win. If profiling shows
this slowing paints, then Ladybird is in good shape.
Update PaintableBox to draw the resize gripper and deconflict
the scrollbars. Set apropriate cursors for scrollbars and gripper in
mousemove. We override EventHandler's cursor handling because nothing
should ever come between a man and his resize gripper.
Chrome metrics use the CSSPixels class. This is good because it's
broadly compatible but bad because they're actually different units
when zoom is not 1.0. If that's a problem, we could make a new type
or just use double.
Previously the logic to compute transitions was split across
`ComputedProperties`, `StyleComputer`, and `Animatable` - this commit
consolidates it all in `ComputedProperties`
The Transformation class wasn't really accomplishing anything. It still
had to store StyleValues, so it was basically the same as
TransformationStyleValue, with extra steps to convert from one to the
other. So... let's just use TransformationStyleValue instead!
Apart from moving code around, the behavior has changed a bit. We now
actually acknowledge unresolvable parameters and return an error when
we try to produce a matrix from them. Previously we just skipped over
them, which was pretty wrong. This gets us an extra pass in the
typed-om test.
We also get some slightly different results with our transform
serialization, because we're not converting to CSSPixels and back.
Previously this was implemented inline within the parsing of
`{repeating}-radial-gradient()` functions but it will also be useful for
`circle()` and `ellipse()`.
We now support the CSS Images Module Level 4 additions to the
`<radial-size>` syntax, namely:
- `<length-percentage>` rather than just `<length>` for circles.
- Distinct `<radial-extent>` values for horizontal and vertical for
ellipses.
- Mixing of `<radial-extent>` and `<length-percentage>` values for
ellipses.
The regressions are due to WPT not being updated to expect the first of
these additions.
Introduce the HTMLSelectedContentElement and integrate it into
<select>, <option> and HTMLParser.
See whatwg/html#10548.
There are two bugs with WPT tests which causes the third subtest
in selectedcontent.html and selectedcontent-mutations.html fail.
See whatwg/html#11882, web-platform-tests/wpt#55849.
This was added in Level 2 of the Web Animations spec
In this level of the spec, all time values associated with animations
(including this duration property) are no longer simple numbers but are
instead either percentages or numbers for progress- and time-based
timelines respectively. These values are represented internally by a new
`TimeValue` wrapper struct, and externally (i.e. in JS) as
`CSSNumberish`.
Font computation and loading is distinct enough from style computation
that it makes more sense to have this in it's own class.
This will be useful later when we move the font loading process to
`ComputedProperties` in order to respect animated values.
This works by generating random values using XorShift128PlusRNG at
compute time and then caching them on the document using the relevant
random-caching-key
