* Fix size of tables in flow layout
The contents of a table can make it bigger than what we would expect
from its 'width', 'min-width', 'height' and ' min-height' properties.
Also, 'width: auto' doesn't stretch it to fill the containing block.
We had to refactor the resolution of margins to happen after layout,
otherwise 'auto' margins wouldn't align correctly.
Co-authored-by: Martin Robinson <mrobinson@igalia.com>
* Feedback
* Consistently use `containing_block_for_table` in table layout
* Update test result
---------
Co-authored-by: Martin Robinson <mrobinson@igalia.com>
Synthetic small caps is supported by the font subsystem, but this is
disabled in Layout 2020. We can turn this on to bring support to parity
with the old layout system.
In addition to turning on synthetic small-caps this change also improves
the way that they work. Before, synthetic small caps meant that every
character was a small version of capitalized character. After this
change, capital letters are larger than small caps versions of small
letters -- matching other browsers and the common expectation of how
small caps works.
In quirks mode, preserved segment breaks should add line height to
lines. This matches the behavior of WebKit and Blink, but not Gecko.
This also handles the special-case of `<br>` elements, which are
implemented with preserved segment breaks via `white-space: pre-line`.
This is an implementation detail though because `<br>` has a special
behavior if the line isn't empty -- it doesn't add any line height in
this case.
Absolutes need to be placed at their hypothetical position as if the
position value was static. This position differs based on the value they
had before blockification. The code for placing absolutes was taking
into account the original display for the inline value, but not for the
block value. A static `display: block` box would placed at a new block
position past the end of the linebox.
As per HTML [1], <div align="..."> and <center> should behave as if they
had the text-align property set to the corresponding value.
Servo implements that as internal text-align values because there should
the extra effect of aligning block descendants, but that part has not
been implemented yet. This patch only adds support for inline layout.
[1]: https://html.spec.whatwg.org/multipage/rendering.html#flow-content-3
This adds basic support for `text-transform` in a way that is more
complete than legacy layout. There are still many missing elements of
proper `text-transform` support such as:
1. Support for `full-width` and `full-size-kana`
2. Support for grapheme based uppercasing, lowercasing, and
capitalization. These are all done per-code point right now.
3. Support for the language-specific `SpecialCasing.txt` cases for case
mapping such as the ones for Irish and Turkish.
Co-authored-by: Rakhi Sharma <atbrakhi@igalia.com>
This deviates from css2, but it's mandated by css-align, and matches
what other browsers do when no margin is 'auto'.
When some margin is 'auto', this should keep the proper round-tripping
behavior that Gecko and WebKit lack, and Blink recently adopted.
This adds support for table rows, columns, rowgroups and colgroups.
There are few additions here:
1. The createion of fragments, which allows script queries and hit
testing to work properly. These fragments are empty as all cells are
still direct descendants of the table fragment.
2. Properly handling size information from tracks and track groups as
well as frustrating rules about reordering rowgroups.
3. Painting a background seemlessly across track groups and groups. This
is a thing that isn't done in legacy layout (nor WebKit)!
Co-authored-by: Oriol Brufau <obrufau@igalia.com>
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.
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: 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`.
<!-- Please describe your changes on the following line: -->
---
<!-- Thank you for contributing to Servo! Please replace each `[ ]` by
`[X]` when the step is complete, and replace `___` with appropriate
data: -->
- [x] `./mach build -d` does not report any errors
- [x] `./mach test-tidy` does not report any errors
- [x] These changes do not require tests because this should only have
performance impacts.
<!-- Also, please make sure that "Allow edits from maintainers" checkbox
is checked, so that we can help you if you get stuck somewhere along the
way.-->
<!-- Pull requests that do not address these steps are welcome, but they
will require additional verification as part of the review process. -->
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.
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 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>
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.
Earlier versions of inline layout in the new layout system did not
properly support line breaking when unbreakable segments spanned
multiple inline boxes. This change updates inline layout to add support
for that. Now items are added to an unbreakable segment before being
committed to a line.
Co-authored-by: Mukilan Thiyagarajan <mukilan@igalia.com>
Co-authored-by: Oriol Brufau <obrufau@igalia.com>
Flattening the LineItem tree into a token stream will allow for handling
the case where an unbreakable line segment spans multiple inline boxes
which might have different hierarchies. This change also fixes the
handling of the second anonymous fragment of a block-in-inline-split.
Co-authored-by: Oriol Brufau <obrufau@igalia.com>
Co-authored-by: Mukilan Thiyagarajan <mukilan@igalia.com>
After placing a float, FloatBox's layout_into_line_items() was calling
place_line_among_floats() with ifc.current_line.inline_position as the
width of needed by the contents of the line.
The problem is that this amount includes the trailing whitespace advance
and thus it could seem that the in-flow contents wouldn't fit next to
the float.
That's not the case, since collapsible whitespace at the end of the line
is removed, and preserved whitespace hangs.
So this patch subtracts ifc.current_line.trailing_whitespace_advance
when calling place_line_among_floats(), like it was already happening
when computing the available_inline_size.
Fixes#30561
In legacy layout, anonymous text wrappers were inheriting the `overflow`
and `text-overflow` properties. This results in the creation of extra
clipping for these anonymous wrappers which could clip away floats. We
will likely implement `text-overflow` differently in non-legacy layout.
This change marks all legacy layout pseudo elements as "legacy" and also
adds a new pseudo element for non-legacy layout that does not inherit
`overflow`.
Fixes#30562.
Co-authored-by: Oriol Brufau <obrufau@igalia.com>
Improve the calculation of the block size of line boxes and all their
component elements. Even empty spans can increase the size of the line
based on their font-size. Elements that have a line-height should
increase the block size of the line, but that setting should not effect
their own size.
In addition to the new passes there are some new failures
Failing because a progression exposes the real issue these tests are
testing:
- css/css-color/t32-opacity-offscreen-multiple-boxes-1-c.xht
- css/css-color/t32-opacity-offscreen-multiple-boxes-2-c.xht
Likely failing because of vertical-align and another sizing issue:
- css/css-transforms/perspective-untransformable-no-stacking-context.html
Failing because a progression reveals another failure:
- html/rendering/non-replaced-elements/hidden-elements.html
Co-authored-by: Mukilan Thiyagarajan <mukilan@igalia.com>
When a box has overflow, any floats placed in that box will lower the
float ceiling into the overflow. If no float is placed in the box
though, the ceiling should be the block position where the overflow
starts. We already know where this is, because we might be passing a
negative value for the new block position after processing a box
(content_size - actual_size would be negative). This negative value
never raises the ceiling though since a maximum is used.
In the case that there is overflow, this change allows raising the
ceiling, but never passed the lowest float. This necessitates keeping
two values for the ceiling: one for floats and one for non-floats.
Fixes#30304.
* Take forced line breaks into account for intrinsic size
Fixes#30350.
* Don't linebreak on collapsible whitespace
This whitespace can hang off the end of the line, because it will be
trimmed LineItem layout.
* Update float placement after line breakage
Also don't ever line break for collapsible whitespace.
* Fix a few more test cases and clean up
* Renaming according to review comments
