Add a new struct `LayoutBoxBase`, that will be used throughout the box
tree. The idea of this struct is that we have a place to consistently
store common layout information (style and node information) and also to
cache layout results such as content sizes (inline and maybe later box
sizes) and eventually layout results.
In addition to the addition of this struct,
`IndependentFormattingContext` is flattened slightly so that it directly
holds the contents of both replaced and non-replaced elements.
This is only added to independent formatting contexts, but will later be
added to all block containers as well.
Signed-off-by: Martin Robinson <mrobinson@igalia.com>
* Refactor computation of preferred aspect ratios
Computing min/max-content sizes required a ContainingBlock in order to
resolve the padding and border when determining the preferred aspect
ratio. However, all callers already knew the padding and border, so they
can compute the ratio themselves, and pass it directly instead of
the ContainingBlock.
Signed-off-by: Oriol Brufau <obrufau@igalia.com>
* Put preferred aspect ratio into ConstraintSpace
Signed-off-by: Oriol Brufau <obrufau@igalia.com>
---------
Signed-off-by: Oriol Brufau <obrufau@igalia.com>
In order to support size keywords in block layout, we may need to call
`inline_content_sizes()` in order to compute the min/max-content sizes.
But this required a mutable reference in order the update the cache,
and in various places we already had mutable references.
So this switches the cache into a RwLock to avoid needing mutable refs.
Note OnceCell wouldn't work because it's not thread-safe.
Signed-off-by: Oriol Brufau <obrufau@igalia.com>
To compute the min-content and max-content inline sizes of a replaced
element, we were only using the aspect ratio to transfer definite block
sizes resulting from clamping the preferred block size between the min
and max block sizes.
However, if the preferred block size is indefinite, then we weren't
transfering the min and max through the aspect ratio.
This patch adds a `SizeConstraint` enum that can represent these cases,
and a `ConstraintSpace` struct analogous to `IndefiniteContainingBlock`
but with no inline size, and a `SizeConstraint` block size.
Signed-off-by: Oriol Brufau <obrufau@igalia.com>
This is the second flexbox caching change. It seeks to detect when a
relayout can be avoided in the case of a stretching flex item. This
heuristic can be combined, because currently we still do relayout
sometimes when we do not need to.
For instance currently we always relayout when a flex child is itself a
column flex. This only needs to happen when the grandchildren themselves
grow or shrink. That optimization is perhaps a lower priority as
`flex-grow: 0 / flex-shrink: 1` is the default behavior for flex.
Since this change means we more consistenly zero out the percentage part
of `calc` expressions when they have circular dependencies, this causes one
test to start failing (`/css/css-values/calc-min-height-block-1.html`).
This is related to w3c/csswg-drafts#10969, which is pending on further
discussion in the working group.
Signed-off-by: Martin Robinson <mrobinson@igalia.com>
Co-authored-by: Oriol Brufau <obrufau@igalia.com>
When computing the min-content size of an inline formatting context,
we could allow a soft wrap opportunity at the start of a text run.
This shouldn't happen with `text-wrap-mode: nowrap`.
Signed-off-by: Oriol Brufau <obrufau@igalia.com>
The result of `inline_content_sizes()` may depend on the block size of
the containing block, so we were always recomputing in case we got
a different block size.
However, if no content has a vertical percentage or stretches vertically,
then we don't need to recompute: the result will be the same anyways.
Signed-off-by: Oriol Brufau <obrufau@igalia.com>
Co-authored-by: Martin Robinson <mrobinson@igalia.com>
Adds support for min-content, max-content, fit-content and stretch,
for atomic inlines.
There are some new test failures because we don't support vertical
writing modes nor `transition-behavior:allow-discrete`.
Signed-off-by: Oriol Brufau <obrufau@igalia.com>
Instead of a blocking a layout thread on the generation of WebRender
`FontKey`s and `FontInstanceKey`s, generate the keys ahead of time and
send the font data to WebRender asynchronously. This has the benefit of
allowing use of the font much more quickly in layout, though blocking
display list sending itself on the font data upload.
In order to make this work for web fonts, `FontContext` now asks the
`SystemFontService` for a `FontKey`s and `FontInstanceKey`s for new web
fonts. This should happen much more quickly as the `SystemFontService`
is only blocking in order to load system fonts into memory now. In
practice this still drops layout thread blocking to fractions of a
millisecond instead of multiple milliseconds as before.
In addition, ensure that we don't send font data or generate keys for
fonts that are used in layout but never added to display lists. This
should help to reduce memory usage and increase performance.
Performance of this change was verified by putting a microbenchmark
around `FontContext::create_font` which is what triggered font key
generation.
Signed-off-by: Martin Robinson <mrobinson@igalia.com>
This will allow callers to start obeying `min-content`, `max-content`,
`fit-content` and `stretch` in follow-up patches.
The old functionality is kept as deprecated methods that we should
eventually remove.
This patch has very little impact on the existing behavior, just some
very minimal implementation of the keywords for css tables.
This also overhauls fixed-layout-2.html since:
- It had code that wasn't doing anything
- It had wrong expecations in prose
- The logic seemed broken in general
- All browsers were failing one testcase
Signed-off-by: Oriol Brufau <obrufau@igalia.com>
This also makes a couple small improvements:
- Rename `IntrinsicSizes` to `NaturalSizes` which reflects more
modern spec language.
- Move the conversion of Stylo's `ImageRendering` to WebRender's
version to a `ToWebRender` trait implementation.
Signed-off-by: Martin Robinson <mrobinson@igalia.com>
Co-authored-by: Oriol Brufau <obrufau@igalia.com>
If we encountered a preserved line break after some whitespace, we were
including the space in the max-content size of the following line.
So just like `line_break_opportunity()` was already clearing
`self.pending_whitespace.min_content`, `forced_line_break()` needs to
clear `self.pending_whitespace.max_content` too.
Also some cosmetic refactoring.
Signed-off-by: Oriol Brufau <obrufau@igalia.com>
When computing the ascent and descent in an inline formatting context,
we weren't taking into account that app units have precision limitations.
Therefore, in some cases we were getting a line height that was slightly
taller than the value specified in `line-height`.
Signed-off-by: Oriol Brufau <obrufau@igalia.com>
Co-authored-by: Martin Robinson <mrobinson@igalia.com>
There were various cases like `text-wrap-mode: nowrap` and
`white-space-collapse: break-spaces` that weren't handled well.
Fixes#33335
flexbox_flex-formatting-interop.html fails now because we don't support
`table-layout: fixed`.
Signed-off-by: Oriol Brufau <obrufau@igalia.com>
This change removes the `effective_writing_mode` concept and tries to
properly implement right-to-left layout support for all non-inline
writing modes. In general, what needs to happen is that rectangles
need to be converted to physical rectangles using the containing block.
A right-to-left rectangle's inline start is on the right physical side
of the containing block. Likewise a positive inline offset in
right-to-left text is a negative physical one.
The implementation here is pretty good for most layout modes, but floats
are still a bit in process. Currently, floats are processed in the
logical layout of the block container, but there still might be issues
with float interaction with mixed RTL and LTR.
While this does move us closer to supporting vertical writing modes,
this is still unsupported.
New failures:
- Vertical writing mode not supported:
- `/css/CSS2/floats/floats-placement-vertical-001b.xht`
- `/css/CSS2/floats/floats-placement-vertical-001c.xht`
- Absolutes inlines should avoid floats (#33323)
- `/css/css-position/position-absolute-dynamic-static-position-floats-004.html`
- No support for grid
- `/css/css-align/self-alignment/self-align-safe-unsafe-grid-003.html`
- `/css/css-position/static-position/inline-level-absolute-in-block-level-context-009.html`
- `/css/css-position/static-position/inline-level-absolute-in-block-level-context-010.html`
- Cannot reproduce these locally on any platform. Very mysterious:
- `/css/css-tables/row-group-margin-border-padding.html`
- `/css/css-tables/row-margin-border-padding.html`
- Exposes bugs we have related to hanging whitespace in preserved
whitespace inlines:
- `/css/css-text/white-space/trailing-space-and-text-alignment-rtl-003.html`
- `/css/css-text/white-space/white-space-pre-wrap-trailing-spaces-023.html`
Signed-off-by: Martin Robinson <mrobinson@igalia.com>
Co-authored-by: Rakhi Sharma <atbrakhi@igalia.com>
* Use app unit in `ComputedValuesExt`
Co-authored-by: Martin Robinson <mrobinson@igalia.com>
Signed-off-by: atbrakhi <atbrakhi@igalia.com>
* Some miscellaneous fixes
Signed-off-by: Martin Robinson <mrobinson@igalia.com>
* remove redundant defination of `containing_block_inline_size`
Signed-off-by: atbrakhi <atbrakhi@igalia.com>
---------
Signed-off-by: atbrakhi <atbrakhi@igalia.com>
Signed-off-by: Martin Robinson <mrobinson@igalia.com>
Co-authored-by: Martin Robinson <mrobinson@igalia.com>
This implements the requirements outlined in the [flexbox specification]
about how to position absolute children of flex containers. We must
establish a static position rectangle (to use if all insets are auto)
and also align the child into that rectangle.
[flebox specification]: https://drafts.csswg.org/css-flexbox/#abspos-items
Signed-off-by: Martin Robinson <mrobinson@igalia.com>
Co-authored-by: Oriol Brufau <obrufau@igalia.com>
This change fixes all rustdoc errors and also adds a tidy check for a
very common rustdoc URL issue. Eventually rustdoc warnings should likely
cause the build to fail, but this catches those issues sooner in order
to not waste so much developer time.
Signed-off-by: Martin Robinson <mrobinson@igalia.com>
When inline atomics establish containing blocks for absolute
descendants, layout should happen with those atomics as the containing
block. This ensures that the absolute descendents have the correct
containing block and Fragment parent. This wasn't happening before and
this change fixes that.
Signed-off-by: Martin Robinson <mrobinson@igalia.com>
Co-authored-by: Oriol Brufau <obrufau@igalia.com>
In particular, this takes into account that flex items may be stretched,
and if they have an aspect ratio, we ma6y need to convert the stretched
size through the ratio.
Signed-off-by: Oriol Brufau <obrufau@igalia.com>
Co-authored-by: Martin Robinson <mrobinson@igalia.com>
When computing the min-content or max-content size of an element we
need to ignore `inline-size`, `min-inline-size` and `max-inline-size`.
However, we should take the block-axis sizing properties into account.
That's because the contents could have percentages depending on them,
which can then affect their inline size via an aspect ratio.
Therefore, this patch adds `IndefiniteContainingBlock`, which is similar
to `ContainingBlock`, but it allows an indefinite inline-size. This
struct is then passed arround during intrinsic sizing.
More refinement will be needed in follow-up patches in order to fully
address the problem.
Signed-off-by: Oriol Brufau <obrufau@igalia.com>
Co-authored-by: Martin Robinson <mrobinson@igalia.com>
Consider a block container that establishes an inline formatting context
and has a definite `block-size` which is clamped by `min-block-size` or
`max-block-size`.
We were already sizing such container correctly, however, its contents
were resolving their percentages against the unclamped `block-size`
value.
This patch fixes the `ContainingBlock` that we pass to the contents so
that they resolve percentages correctly.
Signed-off-by: Oriol Brufau <obrufau@igalia.com>
Co-authored-by: Martin Robinson <mrobinson@igalia.com>
- Rename `InlineFormattingContextState` to
`InlineFormattingContextLayout`.
- Have `InlineFormattingContextLayout` hold a reference to the
`InlineFormattingContext`, so that it does not need to be passed
around as an argument
- Have `LineItemLayout` hold a reference to
`InlineFormattingContextLayout` to avoid duplicating so much data.
- Rename some members of `LineItemLayout` to make it clearer what
they do.
- Give beter names to many lifetimes and combine some that are
effectively the same.
Signed-off-by: Martin Robinson <mrobinson@igalia.com>
Co-authored-by: Rakhi Sharma <atbrakhi@igalia.com>
This adds supports for right-to-left text assigning bidi levels to all
line items when necessary. This includes support for the `dir` attribute
as well as corresponding CSS properties like `unicode-bidi`. It only
implements right-to-left rendering for inline layout at the moment and
doesn't include support for `dir=auto`. Because of missing features,
this causes quite a few tests to start failing, as references become
incorrect due to right-to-left rendering being active in some cases,
but not others (before it didn't exist at all).
Analysis of most of the new failures:
```
- /css/css-flexbox/gap-001-rtl.html
/css/css-flexbox/gap-004-rtl.html
- Require implementing BiDi in Flexbox, because the start and
end inline margins are opposite the order of items.
- /css/CSS2/bidi-text/direction-applies-to-*.xht
/css/CSS2/bidi-text/direction-applies-to-002.xht
/css/CSS2/bidi-text/direction-applies-to-003.xht
/css/CSS2/bidi-text/direction-applies-to-004.xht
- Broken due to a bug in tables, not allocating the
right amount of width for a column.
- /css/css-lists/inline-list.html
- This fails because we wrongly insert a soft wrap opportunity between the
start of an inline box and its first content.
- /css/css-text/bidi/bidi-lines-001.html
/css/css-text/bidi/bidi-lines-002.html
/css/CSS2/text/bidi-flag-emoji.html
- We do not fully support unicode-bidi: plaintext
- /css/css-text/text-align/text-align-end-010.html
/css/css-text/text-align/text-align-justify-006.html
/css/css-text/text-align/text-align-start-010.html
/html/dom/elements/global-attributes/*
- We do not support dir=auto yet.
- /css/css-text/white-space/tab-bidi-001.html
- Servo doesn't support tab stops
- /css/CSS2/positioning/abspos-block-level-001.html
/css/css-text/word-break/word-break-normal-ar-000.html
- Do not yet support RTL layout in block
- /css/css-text/white-space/pre-wrap-018.html
- Even in RTL contexts, spaces at the end of the line must hang and
not be reordered
- /css/css-text/white-space/trailing-space-and-text-alignment-rtl-002.html
- We are letting spaces hang with white-space: pre, but they shouldn't
hang.
```
Signed-off-by: Martin Robinson <mrobinson@igalia.com>
Co-authored-by: Rakhi Sharma <atbrakhi@igalia.com>
We want to selectively enable right-to-left writing modes per layout
context. This change makes that possible by allowing access to
`writing-mode` though an interface that always returns the default
horizontal top-to-bottom (implicitly left-to-right) writing mode.
Signed-off-by: Martin Robinson <mrobinson@igalia.com>
Co-authored-by: Rakhi Sharma <atbrakhi@igalia.com>
This change removes restrictions on using the column layout mode of
flexbox and adds an initial implementation of sizing for that flex
direction. There's a lot of missing pieces still, but in some cases this
does render column flexbox.
In particular, there are now two code paths for preferred widths
(intrinsic size) calcuation: one in the main axis (row) and one in
the cross axis (column) corresponding to the flex direciton with
horizontal writing modes.
In addition, `FlexItemBox::inline_content_sizes` is removed in favor of
making `sizing::outer_inline` /
`IndependentFormattingContext::outer_inline_content_sizes` generic
enough to handle using a different value for auto minimum sizes, which
flexbox needs.
Signed-off-by: Martin Robinson <mrobinson@igalia.com>
Co-authored-by: Oriol Brufau <obrufau@igalia.com>
This converts all geometry in the FragmentTree into physical geometry,
doing conversions ahead of time instead of when traversing the fragment
tree. This is necessary to properly implement BiDi in Servo as we need
to know what side borders are on in mixed RTL and LTR contexts.
In addition, fragments are laid out in a particular context and only
that context knows its writing mode. There were issues where were using
one writing mode to lay out and another to convert to phyisical
coordinates. This isn't an issue now since we only use the default
writing mode, but starts to be an issue with BiDi text.
Closes#25564.
Signed-off-by: Martin Robinson <mrobinson@igalia.com>
* Upgrade stylo to 2024-07-16
Signed-off-by: Martin Robinson <mrobinson@igalia.com>
* Use the new `dom` crate from stylo
Signed-off-by: Martin Robinson <mrobinson@igalia.com>
---------
Signed-off-by: Martin Robinson <mrobinson@igalia.com>
Co-authored-by: Oriol Brufau <obrufau@igalia.com>
- Instead of treating captions as a `BlockFormattingContext`, treat it as
a `NonReplacedFormattingContext`, which allows reusing flow layout for
captions -- fixing some issues with sizing.
- Pass in the proper size of the containing block when laying out,
fixing margin calculation.
- Follow the unspecified rules about how various size properties on
captions affect their size.
- Improve linebreaking around atomics, which is tested by
caption-related tests. This fixes intrinsic size calculation regarding
soft wrap opportunities around atomic and also makes the code making
these actual soft wrap opportunities a bit better.
Signed-off-by: Martin Robinson <mrobinson@igalia.com>
Co-authored-by: Mukilan Thiyagarajan <mukilan@igalia.com>
Refactor inline layout to allow rendering line items in the second stage
to be rendered in any order, independent of their parent inline box.
This will allow line items to be reordered, effectively allowing the
splitting of inline boxes, for the purposes of BiDi and any other inline
reordering feature.
Signed-off-by: Martin Robinson <mrobinson@igalia.com>
Co-authored-by: Rakhi Sharma <atbrakhi@igalia.com>
Make using the logical geometry types more ergonomic by having them all
implement `Copy` (at most 4 64-bit numbers), similar to what `euclid`
does. In addition add an implementation of `Neg` for `LogicalVec` and
`LogicalSides` as it will be used in upcoming table implementation code.
This only paints text in input fields. Selection and cursor are still
not painted.
In addition to adding this feature, the change also updates the
user-agent.css with the latest from the HTML specification. Extra
padding and extraneous settings (such as a bogus line-height and
min-height) are also removed from servo.css. This leads to some new
passes.
There are some new passes, this introduces failures as inserting text
reveals issues that were hidden before. Notably:
- failures in `/html/editing/editing-0/spelling-and-grammar-checking/`:
We do not support spell-checking.
- Most of the rest of the new failures are missing features of input
boxes that are also missing in legacy layout.
This crate only takes care of fonts now as graphics related things are
split into other crates. In addition, this exposes data structures at
the top of the crate, hiding the implementation details and making it
simpler to import them.
Signed-off-by: Martin Robinson <mrobinson@igalia.com>
Co-authored-by: Mukilan Thiyagarajan <mukilan@igalia.com>
This accomplishes two things:
1. Makes it easier to iterate through all inline formatting context
items.
2. Will make it possible to easily move back and forth through the tree
of inline boxes, in order to enable reordering and splitting inline
boxes on lines -- necessary for BiDi.
Co-authored-by: Rakhi Sharma <atbrakhi@igalia.com>
Instead of allocating the inline padding and border space on the line,
allocate it on the segment -- which where the inline box start goes.
Co-authored-by: Rakhi Sharma <atbrakhi@igalia.com>
Instead of linebreaking inside each single-font text segment, linebreak
the entire inline formatting context at once. This has several benefits:
1. It allows us to use `icu_segmenter` (already in use from style),
which is written against a newer version of the Unicode spec --
preventing breaking emoji clusters.
2. Opens up the possibility of changing the way that linebreaking and
shaping work -- eventually allowing shaping across inline box
boundaries and line breaking *after* shaping.
Co-authored-by: Rakhi Sharma <atbrakhi@igalia.com>
