It's not safe to hold on to a pointer to the cache slot across layout
work, since the nested layout may end up causing new entries to get
added to the cache, potentially invalidating a cache slot pointer.
Although the algorithm for sizing tracks (rows or columns) is defined
once for both dimensions in the specification
(https://www.w3.org/TR/css-grid-2/#algo-track-sizing), we have
implemented it twice separately for sizing rows and columns.
In addition to code duplication, another issue is that these
implementations of the same algorithm have already diverged in some
places, and this divergence is likely to become even worse as our
implementation evolves.
This change unifies code for both dimension into one method that runs
track sizing.
While this change brings a bit of collateral damange (border.html and
minmax.html got changes in layout snaphots) it ultimately brings more
benefits because now we can evolve layout for both rows and colums
without duplicating the code :)
`Length::resolved(Node&)` transforms infinite values to "auto".
Following transformations:
Infinite (Length) -> "auto" -> 0 (px)
cause border-box width to be resolved in zero when it should be inf px.
Removing `Length::resolved(Node&)` makes it work right:
Infinite (Length) -> Infinite (px)
Fixes#18649
Since this FIXME was added the SVGFormattingContext has got a fair bit
more spec compliant. The other more specific FIXMEs in this file should
be more useful.
https://www.w3.org/TR/CSS22/visuren.html#floats says that when a box
establishes BFC it should not overlap with floats. The way to avoid
overlaps is up to implementor. This change implements avoiding overlap
by narrowing width of a box because it seems like what other engines
do (in the scenarios I tested).
Calculating width of a box in BFC requires having resolved y to be able
to check if a box overlaps with any floating boxes.
This change makes compute_width() to be called after finding y
position. That also required to move resolving of vertical metrics
in the beginning of a box layout process to have vertical margins
resolved before finding y position.
When there are floats present inside an IFC, we must coordinate with
the parent BFC to calculate the automatic width of the IFC's block box.
This is because the IFC is not directly aware of floats. Only the BFC
knows enough about them to account for them in automatic sizing.
This patch does three things:
- Factors out the code that determines whether a box will create a new
formatting context for its children (and which type of context)
- Uses that code to mark all formatting context roots in layout tree
dumps. This makes it much easier to follow along with layout since
you can now see exactly where control is transferred to a new
formatting context.
- Rebaselines all existing layout tests, since the output format has
changed slightly.
The Display class already supported all specific values, and now they
will be parsed too. The display property now has a special type
DisplayStyleValue.
Fixes the problem that width is incorrectly computed in intrinsic
sizing mode when there are blocks that have min-width or max-width
specified.
Actually that is just the fix of a symptom of the larger problem that
Length::to_px() returns 0 when value is auto regardless of available
size.
This fix resolves issue where calculating the min size of a block could
result in incorrect value if width of the block's children was
compensated by margins to fit into container width (which is equal to 0
during min size calculation).
When we determine that a size is definite because it can be resolved now
without performing layout, we also need to account for the box-sizing
property.
This lets us remove a hack from flex layout where box-sizing:border-box
was manually undone at one point in the layout algorithm.
These functions no longer do anything interesting and just forward to
content_width/content_height. Let's make the callers use those directly
instead and remove this indirection layer.
This commit implements following missing steps in table layout:
- Calculate final table height
- Resolve percentage height of cells and rows using final table height
- Distribute avilable height to table rows
If total max columns width (grid_max) is zero then available width
should be divided equally between columns. Previously there was
division by zero: `column.max_width / grid_max`.
This bit is mostly ad-hoc for now. This simply turns fill: url(#grad1)
into document().get_element_by_id('grad1') then resolves the gradient.
This seems to do the trick for most use cases, but this is not
attempting to follow the spec yet to keep things simple.
Previously, the minimum height of a table row was calculated based
on the automatic height of the cells inner layout. This change makes
computed height of a cell boxes also be considered if it has definite
value.
For example, it's possible to access Node::computed_values() on a node
that neither has style nor a parent with style. This ultimately results
in a null pointer dereference when we return parent()->computed_values()
as a fallback. This can be a little tricky to track down due to these
functions being inlined, so add an explicit verification.
If there is a remaining margin-bottom in margin collapsing state
tracker after laying out all boxes in the current BFC, it must be
assigned to the last in-flow child since margin collapsing cannot
occur across a formatting context boundary.
The current issue where margin-bottom may be counted twice due to
"collapse through" margins in the last in-flow child box is addressed
with this fix by excluding such boxes during the search for a box to
assign the remaining margin.
Test case coming with this fix has a layout bug with incorrectly
computed line height.
This fixes a bug that was seen when a combination of the grid having
been floated with `float: left` and a `minmax()` column size were used.
The issue was that a grid track size should be considered intrinsically
sized if both the min and max sizes are intrinsic, not just one of them.
It returns a PaintableBox (a PaintableWithLines, to be specific), not a
'PaintBox'. paintable_box() without the cast is already available
through BlockContainer's Box base class, we don't need to shadow it.
Now that LengthStyleValue never contains `auto`, IdentifierStyleValue is
the only type that can hold an identifier. This lets us remove a couple
of virtual methods from StyleValue.
I've kept `has_auto()` and `to_identifier()` for convenience, but they
are now simple non-virtual methods.
This is far from perfect, but let's at least make an attempt at laying
out <svg> when encountering it inside another <svg>.
This makes https://awesomekling.substack.com actually load and render
instead of asserting. :^)
Although the spec doesn't mention it, if a flex item has box-sizing:
border-box, and the specified size suggestion is a definite size, we
have to subtract the borders and padding from the size before using it.
This fixes an issue seen in "This Week in Ladybird #4" where the
screenshots ended up in one long vertical stack instead of paired up
2 by 2.
This attribute is used to define how the viewBox should be scaled.
Previously the behaviour implemented was that of "xMidYMid meet", now
all of them work (expect none :P).
With this the Discord login backend is now correctly scaled/positioned.
This also brings our SVG code a little closer to the spec! With spec
comments and all :^)
(Minor non-visible update to layout tests)
When sizing a flex container with flex-direction:column under a
max-content height constraint, we were incorrectly truncating the
infinite available height to 0 when collecting flex items into lines.
This caused us to put every flex item in its own flex line, which is the
complete opposite of what we want during max-content intrinsic sizing,
as the layout would grow wide but not tall.
