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.
compute_inset() was incorrectly retrieving the containing block size
because containing_block() is unaware of grid areas that form a
containing block for grid items but do not exist in the layout tree.
With this change, we explicitly pass the containing block into
compute_inset(), allowing it to correctly provide the containing block
sizes for grid items.
- Include vertical border spacing in row group offset calculation so
that they are axis-aligned with child row/cell elements. This makes it
so there isn't horizontal and vertical overflow caused by child
row/cell elements.
- Include horizontal border spacing in tr width calculations. This makes
it so tr elements don't have overflow anymore when there are multiple
columns.
- Apply vertical caption offset to row group top offset.
- Don't double-count top padding when calculating vertical offset for
tr and row groups.
- Add support for placement of abspos items into track formed by last
line and padding edge of grid container
- Correctly handle auto-positioned abspos items by placing them between
padding edges of grid container
Fixes crashing on https://wpt.live/css/css-grid/abspos/positioned-grid-descendants-001.html
..and delay static position calculation in IFC until trailing
whitespace are removed, because otherwise it's not possible to correctly
calculate x offset.
Containing block for abspos grid items depends on their grid placement:
- if element has definite grid position, then corresponding grid area
should be used as a containing block
- if element does not have definite grid position, then padding edge of
grid container should be used as a containing block
So offset should be adjusted for paddings only for boxes without
definite grid position.
The `calculate_inner_width()` and `calculate_inner_height()` resolve
percentage paddings using the width returned by
`containing_block_width_for()`. However, this function does not account
for grids where the containing block is defined by the grid area to
which an item belongs.
This change fixes the issue by modifying `calculate_inner_width()` and
`calculate_inner_height()` to use the already resolved paddings from the
layout state. Corresponding changes ensure that paddings are resolved
and saved in the state before box-sizing is handled.
As a side effect, this change also improves abspos layout for BFC where
now paddings are resolved using padding box of containing block instead
of content box of containing block.
Fixes yet another case of GFC bug, where Node::containing_block() should
not be used for grid items, because their containing block is grid area
which is not represented in layout tree.
Although the parameter is named "available size," it is always supposed
to represent the containing block size whenever it has a definite value.
Therefore, it is possible to simply use this value instead of performing
a containing block lookup.
This change actually improves correctness for grid items whose
containing block is defined by the grid area, as
`Node::containing_block()` does not account for this.
Change try_compute_width() to check whether min-width/max-width or width
is auto instead of always using `computed_values.width()`.
`grid/min-max-content.html` test is affected but it's progression.
Before this change, a formatting context was responsible for layout of
absolutely positioned boxes whose FC root box was their parent (either
directly or indirectly). This only worked correctly when the containing
block of the absolutely positioned child did not escape the FC root.
This is because the width and height of an absolutely positioned box are
resolved based on the size of its containing block, so we needed to
ensure that the containing block's layout was completed before laying
out an absolutely positioned box.
With this change, the layout of absolutely positioned boxes is delayed
until the FC responsible for the containing block's layout is complete.
This has affected the way we calculate the static position. It is no
longer possible to ask the FC for a box's static position, as this FC's
state might be gone by the time the layout for absolutely positioned
elements occurs. Instead, the "static position rectangle" (a concept
from the spec) is saved in the layout state, along with information on
how to align the box within this rectangle when its width and height are
resolved.
Fixes implementation of the following line from the spec:
"However, limit the growth of any fit-content() tracks by their
fit-content() argument."
Now we correctly apply a limit to increased growth limit rather than to
the planned increase.
Change in "Tests/LibWeb/Layout/input/grid/fit-content-2.html" is a
progression and "Item as wide as the content." is actually as wide as a
content.
When deciding if the grid containers min size should be limited by a
max size. Check for a max height or width depending on the dimension,
instead of just always checking for a max width.
Implements:
"If the product of the hypothetical fr size and a flexible track’s flex
factor is less than the track’s base size, restart this algorithm
treating all such tracks as inflexible."
Fixes https://github.com/LadybirdBrowser/ladybird/issues/1211
According to https://www.w3.org/TR/css-grid-2/#placement-shorthands
when setting the 'grid-row' and 'grid-column' shorthand property to a
single <custom-ident> value, both 'grid-row-start'/'grid-column-start'
and 'grid-row-end'/'grid-column-end' should be set to that
<custom_ident>.
Areas are disassembled into boundary lines on `build_grid_areas()` step,
so we can always use them to find grid item's position during placement.
This way we support both ways to define area: `grid-template-areas` and
implicitly using `-start` and `-end` boundary line names.
- Change min track sizing function to be "auto" when flex size is
specified.
- Never check if min track sizing funciton is flexible, because only
max is allowed to be flexible.
- Address FIXME in automatic_minimum_size to avoid regressions after
making two fixes mentioned above.
When traversing the layout tree to find an appropriate box child to
derive the baseline from. Only the child's margin and offset was being
applied. Now we sum each offset on the recursive call.
Before this change, we only considering `grid-auto-flow` to determine
whether a row or column should be added when there was not enough space
in the implicit grid to fit the next unplaced item.
Now, we also choose the direction in which the "auto placement cursor"
is moved, based on the auto flow property.
With this change "max-width: max-content" is treated as "none" when
the available width is also "max-content". This fix prevents a stack
overflow in the grid track size maximization algorithm by avoiding
recursive calls to calculate_max_width() when determining the maximum
grid container size.
Now, we will evenly distribute the remaining free space across tracks
using the auto max-tracks sizing function, exactly as the specification
states. Many tests are affected, but they are not visually broken.
Fixes https://github.com/SerenityOS/serenity/issues/22798
This is a part of refactoring towards making the paintable tree
independent of the layout tree. Now, instead of transferring text
fragments from the layout tree to the paintable tree during the layout
commit phase, we allocate separate PaintableFragments that contain only
the information necessary for painting. Doing this also allows us to
get rid LineBoxes, as they are used only during layout.
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.
This change fixes the function that calculates the number of auto-fill
tracks, ensuring it uses height when applied to rows, instead of
assuming that it always operates on columns.
Fixes the mistake that gaps are counted as if they exist after each
track, when actually gaps are present only between tracks.
Visual progression on https://kde.org/products/
CSSPixels should not be wrapped into CSS::Length before being passed
to resolved() to end up resolving percentages without losing
precision.
Fixes thrashing layout when 33.3333% width is used together with
"box-sizing: border-box".
Percentage vertical margin and padding values are relative to the
containing block *width*, not *height*. This has to be one of the most
commonly recurring mistakes we make :^)
Before this change, parsed grid-template-columns/grid-template-rows
were represented as two lists: line names and track sizes. The problem
with this approach is that it erases the relationship between tracks
and their names, which results in unnecessarily complicated code that
restores this data (incorrectly if repeat() is involved) during layout.
This change solves that by representing line definitions as a list of
sizes and names in the order they were defined.
Visual progression https://genius.com/
