Browsers such as Chrome and Firefox apply an arbitrary scale to the
current font size if `normal` is used for `line-height`. Firefox uses
1.2 while Chrome uses 1.15. Let's go with the latter for now, it's
relatively easy to change if we ever want to go back on that decision.
This also requires updating the expectations for a lot of layout tests.
The upside of this is that it's a bit easier to compare our layout
results to other browsers', especially Chrome.
It's safe to remove this pointer because intrinsic layout should never
look up a box's state beyond its containing block.
This change affects the expectations of two layout tests, but both
already differ slightly from other browsers, and the difference between
expectations is less than 5px.
This essentially reverts 1b46a52cfc
and adds more tests.
The reverted change was an incorrect workaround for the real issue,
which was that we weren't creating anonymous wrapper boxes around inline
children of table-cell boxes.
Now that this has been fixed, we can go back to aligning text properly.
This fixes an issue where CSS vertical-align on a table-cell box would
incorrectly apply to both the table-cell box and any inline content it
had inside.
By the time we're measuring the height of a BFC root, we've already
collapsed all relevant margins for the root and its descendants.
Given this, we should simply use 0 (relative to the BFC root) as the
lowest block axis coordinate (i.e Y value) for the margin edges.
This fixes a long-standing issue where BFC roots were sometimes not tall
enough to contain their children due to margins.
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.
InlinePaintable was an ad-hoc paintable type required to support the
fragmentation of inline nodes across multiple lines. It existed because
there was no way to associate multiple paintables with a single layout
node. This resulted in a lot of duplicated code between PaintableBox and
InlinePaintable. For example, most of the CSS properties like
background, border, shadows, etc. and hit-testing are almost identical
for both of them. However, the code had to be duplicated to account for
the fact that InlinePaintable creates a box for each line. And we had
quite many places that operate on paintables with a code like:
```
if (box.is_paintable_box()) {
// do something
} else (box.is_inline_paintable()) {
// do exactly the same as for paintable box but using InlinePaintable
}
```
This change replaces the usage of `InlinePaintable` with
`PaintableWithLines` created for each line, which is now possible
because we support having multiple paintables per layout node. By doing
that, we remove lots of duplicated code and bring our implementation
closer to the spec.
- 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.
Adds additional padding to the end-side of the scrollable overflow
rectangle as necessary to enable a scroll position that satisfies
the requirements of `place-content: end` alignment.
This code previously only allocated enough space in
m_col_elements_by_index for 1 slot per column, meaning that columns
with a span > 1 would write off the end of it.
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.
This line changes padding top to align cell content to baseline:
`cell.padding_top += m_rows[cell.row_index].baseline - cell.baseline`
Which means available for distribution height `height_diff` could have
changed so it needs to be refreshed before assigning the rest of it to
padding bottom:
`cell_state.padding_bottom += height_diff;`
Fixes https://github.com/SerenityOS/serenity/issues/22032
Table wrappers don't quite behave the same as most elements, in that
their computed height and width are not meant to be used for layout.
Instead, we now calculate suitable widths and heights based on the
contents of the table wrapper when performing absolute layout.
Fixes the layout of
http://wpt.live/css/css-position/position-absolute-center-007.html
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 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.
- 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
The final used values for these properties is stored in the layout node,
so we need to make sure they are propagated there as well when doing
table box fixup.
Using flex layout inside button solves the issue with wrongly calculated
height when it has: pseudo element and whitespaces inside.
Also using flex instead of a table layout allows for the same vertical
alignment but with fewer layout nodes: a flex container and anonymous
wrapper for content instead of a table wrapper, table, row, and cell.
If the table used width has to be adjusted because of a cell with
percentage width, add back the undistributable space due to border
spacing. This is consistent with the width distribution algorithm, which
sets aside the undistributable space and the behavior of other browsers.
`DeprecatedString::to_int` calls `StringUtils::convert_to_int`
internally. However, the integer parsing is not done in an HTML
spec-compliant way. For example, `colspan="2;"` is valid according to
the spec. But, with the current implementation, we will fail to parse
"2;", and instead fall back to using 1 as the colspan value.
This patch changes the `HTMLTableCellElement::col_span` and
`HTMLTableCellElement::row_span` methods to use the
`Web::HTML::parse_non_negative_integer` function that will parse the
attribute value in an HTML spec-compliant way.
Check the width of the next token after white space to decide line
breaks. The next width can also be the total width of multiple tokens.
This better follows the CSS Text specification and matches behavior of
other browsers.
Fixes#20388.
This patch just adds the new root paintable and updates the tests
expectations. The next patch will move painting logic from the layout
viewport to the paint viewport.
