This moves white space collapse to right before breaking and shaping
happens, which is more similar to what happens in legacy layout. This is
the first step toward making this procedure more efficient (avoiding
string copies) and also implementing support for `text-transform`.
Co-authored-by: Rakhi Sharma <atbrakhi@igalia.com>
This adds an initial implementation of font fallback, on part with the
one used in legacy layout. There are still issues. For instance, font
matching is done per unicode character rather than based on graphemes or
the shape first approach of Chrome. The idea is that these changes can
be made later.
* Respond to shorthand property requests with real values
Signed-off-by: Sebastian C <sebsebmc@gmail.com>
* Cleanup formatting and old comments
Signed-off-by: Sebastian C <sebsebmc@gmail.com>
* Update WPT expectations
Signed-off-by: Sebastian C <sebsebmc@gmail.com>
* Refactor out helper fn
Signed-off-by: Sebastian C <sebsebmc@gmail.com>
* Cleanup
Signed-off-by: Sebastian C <sebsebmc@gmail.com>
---------
Signed-off-by: Sebastian C <sebsebmc@gmail.com>
This implements a very naive row height allocation approach. It has just
enough to implement `vertical-align` in table cells. Rowspanned cells
get enough space for their content, with the extra space necessary being
allocated to the last row. There's still a lot missing here, including
proper distribution of row height to rowspanned cells.
Co-authored-by: Oriol Brufau <obrufau@igalia.com>
Instead of using the border widths from the style, use the ones recorded
by the `BoxFragment`. This is necessary because inline layout can
override these border widths during fragmentation. For instance, when a
box is split across two lines only one fragment should have an inline
start border.
Instead of tracking justification opportunities during line layout, wait
until the line is about to be laid out and justification is about
happen. This makes the logic for tracking justification opportunities
simpler. In particular, we no longer have to carefully adjust them when
trimming whitespace. Additionally, this avoids a bit of work unless
justification is turned on.
This also includes a small cleanup of the justification code.
This change starts collecting the starting baseline set for fragments,
which is necessary for some layout modes (flex and tables, namely) as
well as being important for the implementation of `align-items`. In
addition, it converts baseline measurement to use `Au` everywhere.
Co-authored-by: Oriol Brufau <obrufau@igalia.com>
* use app unit in replaced elements
* more app unit usage
* Avoid unnecessary into()
* Run ./mach fmt
* use scaleby
* update
---------
Co-authored-by: Oriol Brufau <obrufau@igalia.com>
* layout: Round getClientRect queries to pixels properly
Instead of just flooring all pixels in getClientRect queries, we should
round the rectangle.
* Fix scrollWidth/scrollHeight too, and tests
* Tests passing
* Test expectation for legacy layout
---------
Co-authored-by: Oriol Brufau <obrufau@igalia.com>
This adds support for table `border-spacing` property. Note that we do
not yet support the collapsed border model.
Co-authored-by: Oriol Brufau <obrufau@igalia.com>
* layout: Implement computation of table column widths
This change implements the various steps of table column width
computation, ignoring features that don't exist yet (such as separated
borders, column elements, and colgroups).
Co-authored-by: Oriol Brufau <obrufau@igalia.com>
* Fix an issue with the assignment of column percent width
* Respond to review comments
---------
Co-authored-by: Oriol Brufau <obrufau@igalia.com>
Shape text during InlineFormattingContext construction rather than doing
it twice during fragment tree construction. This is a step on the way
toward proper font fallback.
This also moves all `TextRun` related code into `text_run.rs` to try to
trim down the size of `inline.rs`.
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Replaced elements should never be able to have a layout internal
display, according to the specification. This change makes it so that
the used value of replaced element's display is always inline, as the
specification says.
Before counting whitepsace-only `GlyphStore`s where counted as a single
justification opportunity when trimming whitespace from the front and
back of lines. This isn't correct, instead count the actual number of
word seperators of the trimmed `GlyphStore`s.
These two counts can be different in the case where whitespace collapse
isn't happening yet (flexbox). In addition, using word seperators means
the code is making less assumptions about the contents of the line and
is more robust.
This fixes some crashes in flexbox tests on debug builds.
Co-authored-by: Rakhi Sharma <atbrakhi@igalia.com>
Instead of a tricky stack of enum iterators expose a `foreach()`
function on InlineFormattingContext, which takes a `FnMut`. This
prevents callers wanting to iterate from keeping a stack of iterators
and will potentially allow a future version of this function to avoid
borrowing the ArcRefCell<...> of inline boxes for every iteration
(presumably using something like OwnedRef).
Convert `inline_content_sizes` to use this new `foreach()` function and
move the `Computation` out of the function body to
`ContentSizesComputation`. This reduces the stack depth of inline size
computation, because `foreach()` is iterative and not recursive.
This is a preliminary change to removing the second round of text shaping
during layout, because shaping will use this new iterator.
* layout: Add *very* basic support for table layout
This is the first step to proper table layout. It implements a naive
layout algorithm, notably only taking into account the preferred widths
of the first table row. Still, it causes some float tests to start
passing, so turn on the `layout.tables.enabled` preference for those
directories.
Co-authored-by: Oriol Brufau <obrufau@igalia.com>
* Address review comments
* Fix a crash with rowspan=0
* Turn on pref and update results for `/css/css-tables` and `/css/CSS2/tables`
---------
Co-authored-by: Oriol Brufau <obrufau@igalia.com>
This is just a bit of code movement that trims down the size of the
`inline.rs` file in order to make it a bit more manageable. It leads the
way to more refactoring and cleanup in the future.
* layout: Implement support for `line-height` and `vertical-align`
This is an initial implementation of proper `line-height` and
`vertical-align` support. While this change includes the bulk of the
work there are still many missing pieces for full support. In particular
some big missing things are:
- Flex containers do not properly compute their baselines. The idea is
to tackle this in a followup change. This causes various flex tests
to start failing because everything used to be top aligned.
- The implementation of the line-height quirks (only active in quirks
mode) are incomplete. While the quirk works in many cases, there are
still some cases where it is handled incorrectly. This requires more
redesign and refinement, better suited for a followup.
- Most of the features are CSS 3 such as precision control of the
baseline and first and last baselines are not implemented. This
change gets us close to CSS 2.x support.
While there are many new test passes with this change some tests are
starting to fail. An accounting of new failures:
Tests failing also in Layout 2013:
- /css/css2/positioning/toogle-abspos-on-relpos-inline-child.html (only passes in Chrome)
- /css/CSS2/fonts/font-applies-to-001.xht (potentially an issue with font size)
Invalid tests:
- /css/CSS2/visudet/inline-block-baseline-003.xht
- /css/CSS2/visudet/inline-block-baseline-004.xht
- These are are failing in all browsers. See https://bugs.chromium.org/p/chromium/issues/detail?id=1222151.
Missing table support:
- /_mozilla/mozilla/table_valign_middle.html
Missing `font-size-adjust` support :
- /css/css-fonts/font-size-adjust-zero-2.html (also failing in 2013)
Incomplete form field support :
- /html/rendering/widgets/the-select-element/option-add-label-quirks.html (label isn't rendered so button isn't the right size in quirks mode due to line height quirk)
Need support for calculating flexbox baseline:
- /css/css-flexbox/fieldset-baseline-alignment.html
- /css/css-flexbox/flex-inline.html
- /css/css-flexbox/flexbox-baseline-multi-line-horiz-001.html
- /css/css-flexbox/flexbox-baseline-single-item-001a.html
- /css/css-flexbox/flexbox-baseline-single-item-001b.html
Failing because we don't create anonymous inline boxes for text children of blocks:
- /css/CSS2/linebox/anonymous-inline-inherit-001.html
Passes locally (potentially related to fonts):
- /css/CSS2/css1/c414-flt-fit-004.xht
- /css/css-transforms/transform-input-017.html
- /html/obsolete/requirements-for-implementations/the-marquee-element-0/marquee-min-intrinsic-size.html
- /css/css-fonts/first-available-font-005.html
- /css/css-fonts/first-available-font-006.html
* Some cleanups after live review with @mukilan
Also update results.
This adds support for fixing up tables so that internal table elements
that are not properly parented in the DOM have the correct box tree
structure according to the CSS Table specification [1]. Note that this
only comes into play when building the DOM via script, as HTML 5 has its
own table fixups that mean that the box tree construction fixups here
are not necessary.
There are no tests for this change. In general, it's hard to write tests
against the shape of the box tree, because it depends on the DOM. We
plan to test this via WPT tests once layout is complete.
1. https://drafts.csswg.org/css-tables/#table-internal-element
Co-authored-by: Oriol Brufau <obrufau@igalia.com>
This change adds support for `text-align-last` as well as ensuring that
it also applies to lines before forced line breaks. Two tests start to
fail because they rely on right-to-left text to pass:
- /css/css-text/text-align/text-align-last-010.html.ini
- /css/css-text/text-align/text-align-last-011.html.ini
This completes the transition to compiling Servo with rust stable. Some
nightly-only features are still used when compiling the `script` and
`crown` crates, as well as for some style unit tests. These will likely
break with newer compiler versions, but `crown` can be disabled for them
conditionally. This is just the first step.
This has some caveats:
1. We need to disable setting up the special linker on Linux. The -Z
option isn't supported with stable rust so using this is out --
meanwhile we can't be sure that lld is installed on most systems.
2. `cargo fmt` still uses some unstable options, so we need to rely on
the unstable toolchain just for running `fmt`. The idea is to fix this
gradually.
This data structure has all of the metrics needed to render a font and
is in `Au`. We'll need more of these metrics for implementing
`vertical-align` and its use doesn't increase the size of the Fragment
tree (as the BoxFragment is still larger). In addition, this will be
helpful when switching layout to `Au`.
This is the first part of constructing the box tree for table layout. No
layout is actually done and the construction of tables is now hidden
behind a flag (in order to not regress WPT). Notably, this does not
handle anonymous table part construction, when the DOM does not reflect
a fully-formed table. That's part two.
Progress toward #27459.
Co-authored-by: Oriol Brufau <obrufau@igalia.com>
Co-authored-by: Manish Goregaokar <manishsmail@gmail.com>
* Use `Option` instead of `Result` when passing optional values into vector
Also renames vector and adds comment for clarity, just in case that's helpful
Signed-off-by: Joshua Holmes <joshua.phillip.holmes@gmail.com>
* Replace use of Option with new enum, , when seperating flex content
Signed-off-by: Joshua Holmes <joshua.phillip.holmes@gmail.com>
* Move global function body into the method
Signed-off-by: Joshua Holmes <joshua.phillip.holmes@gmail.com>
---------
Signed-off-by: Joshua Holmes <joshua.phillip.holmes@gmail.com>
The changes in #30740, fixed an issue where certain characters should
prevent line break opportunity after atomics. This change extends that
to also apply to before atomics, which is what the specification says
should happen.
We previously sent a " " to the linebreaker in order to ensure that the
next text had a soft wrap opportunity at the start. Calling `next(" ")`
without waiting until the returned index was 1, violated some
invariants of linebreaker ultimately causing a panic.
Instead of using the linebreaker for this, simply keep a flag in the
IFC layout state, which avoids the problem entirely.
Fixes#30703.
* Add initial support for sticky positioning for non-legacy layout
Many tests still fail for a variety of reasons. One of the primary ones
is that CSSOM currently does not return correct values for elements
positioned by sticky nodes. This requires changes to WebRender to work
properly.
* Fix an assertion failure in the legacy layout sticky code
Layout asserts that it never creates stacking contexts that have a zero
scale, yet it doesn't prevent the creation of those stacking contexts.
This change stops their creation at an earlier stage.
Fixes#30118.
* convert border and padding to app units in flexbox
* convert margin to app units in flexbox
* cleanup, fmt
* add todo comment
* fmt
* add comment
* use Length instead of CSSPixelLength: they are same
