Spec: https://drafts.csswg.org/css-sizing-3/#funcdef-width-fit-content
It's similar to the `fit-content` keyword but, instead of clamping the
stretch size between `min-content` and `max-content`, it clamps the
provided argument.
So now that we support `fit-content`, it's quite straightforward to add.
It's just not completely clear what should happen when the argument has
a cyclic percentage, so this may need some further adjustments depending
on the outcome of https://github.com/w3c/csswg-drafts/issues/11805
Signed-off-by: Oriol Brufau <obrufau@igalia.com>
In #35630 I treated an indefinite `stretch` as 0px on min sizing
properties, and as `none` on max sizing properties. However, this was
only for final layout sizes, I forgot about intrinsic contributions.
Blink already modified the relevant test, I'm just reordering it a bit
since we are no longer treating `stretch` as `fit-content`, so it seems
better to test it at the end.
Signed-off-by: Oriol Brufau <obrufau@igalia.com>
* Use 2024 style edition
Signed-off-by: Simon Wülker <simon.wuelker@arcor.de>
* Reformat all code
Signed-off-by: Simon Wülker <simon.wuelker@arcor.de>
---------
Signed-off-by: Simon Wülker <simon.wuelker@arcor.de>
layout: Basic implementation of size keywords on `flex-basis`
This splits the logic to resolve the used value of `flex-basis` into its
own method, which preserves size keywords.
And then it changes `flex_base_size()` to resolve the provided keywords
properly. However, it doesn't handle size keywords in the cross axis.
Signed-off-by: Oriol Brufau <obrufau@igalia.com>
Some layouts like table need some style overrides. We were handling this
in `ComputedValuesExt`, but it was messy, unreliable and too limited.
For example, we were assuming that a style with `display: table` would
belong to a table wrapper box or table grid box. However, certain HTML
elements can ignore their `display` value and generate a different kind
of box. I think we aren't doing that yet, but we will need this.
Also, resolving the used border of a table needs layout information,
which we don't have in `ComputedValuesExt`. This patch will allow to
improve border collapsing in a follow-up.
Signed-off-by: Oriol Brufau <obrufau@igalia.com>
There were two kinds of layout tracing controlled by the same debugging
option:
- modern layout: Functionality that dumped a JSON serialization of the
layout tree before and after layout.
- legacy layout: A scope based tracing that reported the process of
layout in a structured way.
I don't think anyone working on layout is using either of these two
features. For modern layout requiring data structure to implement
`serde` serialization is incredibly inconvenient and also generates a
lot of extra code.
We also have a more modern tracing functionality based on perfetto that
we have started to use for layout and IMO it's actually being used and
more robust.
Signed-off-by: Martin Robinson <mrobinson@igalia.com>
`width` and `max-width` typically treat expressions with percentages as
their initial value, but for the min-content contribution of replaced
elements, they should instead be treated as zero.
https://drafts.csswg.org/css-sizing-3/#replaced-percentage-min-contribution
Signed-off-by: Oriol Brufau <obrufau@igalia.com>
In order to compute the inline min-content and max-content contributions
of an anonymous block, we were finding its min-content and max-content
inline size with a SizeConstraint coming from the block size of the box.
However, anonymous blocks do not establish a containing block for their
contents, so this patch uses a SizeConstraint from the block size of the
containing block.
Signed-off-by: Oriol Brufau <obrufau@igalia.com>
If a table element had e.g. `width: 0px`, we were assuming that this was
its intrinsic min-content and max-content contributions.
However, tables are always at least as big as its min-content size, so
this patch floors the intrinsic contributions by that amount.
Signed-off-by: Oriol Brufau <obrufau@igalia.com>
in each layout logic, in order to correctly resolve sizing keywords.
This patch adds a new `Sizes` struct which holds the preferred, min and
max sizing values for one axis, and unifies the logic to resolve the
final size into there.
Signed-off-by: Oriol Brufau <obrufau@igalia.com>
Several structs and enums had a `inline_content_sizes()` method, but it
wasn't clear which ones would try to cache the result, and which ones
would always compute it.
Therefore, this performs some clarifying renaming:
- Cached ones stay as `inline_content_sizes()`
- Uncached ones become `compute_inline_content_sizes()`
Also, to simplify calls to `LayoutBoxBase::inline_content_sizes()`,
`compute_inline_content_sizes()` is moved into a new trait.
Signed-off-by: Oriol Brufau <obrufau@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>
- Clamp the stretch size to not be negative when the sum of padding,
borders and margins exceed the available space. This avoids a 2nd
layout.
- Avoid computing the inline content sizes if the result isn't needed.
- Instead of clamping both the min-content and max-content sizes to be
between the min and max constraints, just compute the fit-content size
first, and then clamp. Then `ContentSizes::map()` can be removed.
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>
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>
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>
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>
In particular, `main_content_sizes()` now works with columns.
`layout_for_block_content_size()` is now used for both intrinsic sizes
and intrinsic contributions, a IntrinsicSizingMode parameter is added
to choose the behavior.
Also, we consider the main size of a flex item as indefinite if its flex
basis is indefinite and the flex container has an indefinite main size.
Signed-off-by: Oriol Brufau <obrufau@igalia.com>
Co-authored-by: Martin Robinson <mrobinson@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 change adds a version of row height distribution that follows the
distribtuion algorithm used for tables in Blink's LayoutNG. This is just
an intermediate step toward implementing a distribution algorithm for
both rows and columns more similar to Layout NG.
The CSS Table 3 specification is often wrong with regard to web
compatability, which is why we have abandoned it in favor of the Layout
NG algorithm for row height distribution. this work.
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>
Typically, block-level contents are stacked vertically, so this was just
taking the maximum size among all contents. However, floats can be
stacked horizontally, so we need to sum their sizes.
… and converting them to flow-relative geometric values.
These values are almost always used to size and position a fragment within its containing block, so using the mode of the containing block seems more correct.
Note that the `writing-mode` and `direction` properties are disabled in Servo at the moment, so this PR by itself should have no effect: the writing mode of an element is always the same of that of its containing block since they’re both horizontal rtl.