Before this change, we've been maintaining various StyleComputer caches
at the document level.
This made sense for old-school documents without shadow trees, since
all the style information was document-wide anyway. However, documents
with many shadow trees ended up suffering since any time you mutated
a style sheet inside a shadow tree, *all* style caches for the entire
document would get invalidated.
This was particularly expensive on Reddit, which has tons of shadow
trees with their own style elements. Every time we'd create one of their
custom elements, we'd invalidate the document-level "rule cache" and
have to rebuild it, taking about ~60ms each time (ouch).
This commit introduces a new object called StyleScope.
Every Document and ShadowRoot has its own StyleScope. Rule caches etc
are moved from StyleComputer to StyleScope.
Rule cache invalidation now happens at StyleScope level. As an example,
rule cache rebuilds now take ~1ms on Reddit instead of ~60ms.
This is largely a mechanical change, moving things around, but there's
one key detail to be aware of: due to the :host selector, which works
across the shadow DOM boundary and reaches from inside a shadow tree out
into the light tree, there are various places where we have to check
both the shadow tree's StyleScope *and* the document-level StyleScope
in order to get all rules that may apply.
Use `calculate_inner_height()` and `calculate_inner_width()`, which
account for box-sizing, to resolve the item's size in max-content
contribution calculations.
Fixes a crash on https://www.lego.com/en-gb/product/game-boy-72046 :^)
The apparent regressions in clip-path-interpolation-xywh-rect.html are
because of false positives. Something about the test was causing it to
compare two wrong values that happened to be the same. Now one of the
values is correct, they don't match.
The difference is that parsing as the `color` property's value also
allows the CSS-wide keywords, which we don't want here.
The added test cases make sure that those keywords are *not* valid:
- `color` should inherit its parent value of `orange`
- `background-color` doesn't inherit, so should be its initial value of
`transparent`
`HTML::parse_dimension_value()` doesn't parse units except for `%` for
percentages; it just ignores them and treats it as a number of pixels.
Now that we can parse `<length>` and pals directly, do that instead,
which makes non-px units work.
In a few places, user code wants to parse a `<color>` or `<length>` etc,
but we didn't have a way to do so, so they would do something
similar-ish instead, like parse the value of the `color` property.
Let's make that available instead.
Per the CSS Namespaces spec, an empty string declared in an
@namespace rule represents no namespace.
Fixes WPT:
- css/css-namespaces/prefix-002.xml
- css/css-namespaces/prefix-003.xml
This updates the `parse_text_decoration_line_value` to reject values
which non-exclusively include `none` e.g. `underline none`.
It also simplifies handling by always producing a Vector (except for
`none`) and adding VERIFY_NOT_REACHED in more places which shouldn't be
reachable.
If a CSS rule has a URL like `url("")`, it would resolve to the document
URL itself. There isn't a context in which this would result in a valid
resource, so the spec tells us to drop it.
No test here because there isn't really a way to know when a CSS URL is
fetched. We could use PerformanceResourceTiming, but that is only for
HTTP(S) URLs. There is already an existing test for serialization of
empty URLs, which still passes.
The exception returned here is never used or logged. Let's just return
a null request, to make it clearer that these are not exceptions shown
to the user (thus not observable).
This fixes aliased edges when e.g. applying rotation transforms to
certain shapes or SVGs. Although the clip rects themselves are
rectangular, a non-identity matrix transform can be active for the
canvas.
Fixes#5909.
We always want to return the mapped scaling mode here, since the bitmap
might end up transformed, scaled, etc. and we do not want to fall back
to nearest neighbour in those cases.
This changes Gfx::ScalingMode to reflect the three modes of scaling we
support using Skia, which makes it a bit easier to reason about the mode
to select. New is ::BilinearMipmap, which uses linear interpolation
between mipmap levels to produce higher quality downscaled images.
The cubic resampling options Mitchell and its sibling CatmullRom both
produced weird artifacts or resulted in a worse quality than
BilinearMipmap when downscaling. We might not have been using these
correctly, but the new ::BilinearMipmap method seems to mirror what
Chrome uses for downscaled images.
When we generate pseudo elements, we create anonymous wrappers that
might end up in an InlineNode, even if they have `display: block` set.
This causes them not to be rendered.
Do not rely on inline continuation logic for these anonymous wrappers,
but rather find the first layout parent that's not an InlineNode and
insert it into that.
Fixes#5042.
`play_or_cancel_animations_after_display_property_change` is called
whenever an element is inserted or removed, or it's display property
changes, but it is only required to run if we actually have animations
to play or cancel.
Reduces time spent in the aforementioned function from ~2% to ~0.03%
when loading https://en.wikipedia.org/wiki/2023_in_American_television
There is no need to recreate this each time we need it when we can
instead create it once and then reuse it.
This is stop-gap since we should resolve colors to their computed forms
as part of StyleComputer::compute_properties
Reduces time spent in ColorResolutionContext::for_layout_node from ~1.1%
to ~0.1% when loading
https://en.wikipedia.org/wiki/2023_in_American_television
We don't need to iterate every property in start_needed_transitions,
only those that appear in transition-property or have an existing
transition
Reduces the time spent in start_needed_transitions from ~5% to ~0.03%
when loading https://en.wikipedia.org/wiki/2023_in_American_television
By doing this in computed properties rather than InlineLevelIterator we
only do it once per element rather than once per text fragment.
Reduces runtime of this process from ~15% to ~0.2% when loading
https://en.wikipedia.org/wiki/2023_in_American_television
We simplify these at style computation time so there is no need to
maintain them as {Number|Length}OrCalculated
Reduces the time spent in `Length::ResolutionContext::for_layout_node`
from 3.3% to 0.4% when loading
https://en.wikipedia.org/wiki/2023_in_American_television
