- Out-of-flow items should not affect grid layout
- "The static position of an absolutely-positioned child of a grid
container is determined as if it were the sole grid item in a grid
area whose edges coincide with the content edges of the grid
container."
Fixes infinite spinning in the cases when CSSPixels does not have
enough precision to represent increase per track which happens when
very small extra_space got divided by affected tracks number.
Fixes the issue that before "automatic minimum size" were used to size
flexible tracks even though specification says is should be "minimum
contribution"
In c66dbc99ee GFC was updated to use -1
as special value for the infinite growth limit. However, using Optional
instead reduces the risk of accidentally using -1 special value in
layout calculations.
Using fixed-point saturated arithmetics for CSSPixels allows to avoid
accumulating floating-point errors.
This implementation is not complete yet: currently saturated
arithmetics implemented only for addition. But it is enough to not
regress any of layout tests we have :)
See https://github.com/SerenityOS/serenity/issues/18566
This is the preparation to use fixed-point to represent CSSPixels.
Previously, it was acceptable to divide CSSPixels by zero, resulting
in inf, but after migrating to fixed-point stored as an integer, it
would lead to undefined behavior.
This is preparation for introducing fixed-point CSSPixels in upcoming
commits.
Infinity is a valid state for the growth limit value of a grid track.
It was possible to use INFINITY when CSSPixels were represented using
floating point, but it won't work after the transition to fixed point,
which is represented using integers. This change addresses this by
using -1 as a special value to represent the infinite state of the
growth limit.
This change implements following paragraph from placement algorithm in
the spec:
"If the largest column span among all the items without a definite
column position is larger than the width of the implicit grid, add
columns to the end of the implicit grid to accommodate that column
span."
There were places in the grid implementation code with copies of this
text, but those were completely unrelated to the code where they were
being pasted so I removed them.
Although DistinctNumeric, which is supposed to abstract the underlying
type, was used to represent CSSPixels, we have a whole bunch of places
in the layout code that assume CSSPixels::value() returns a
floating-point type. This assumption makes it difficult to replace the
underlying type in CSSPixels with a non-floating type.
To make it easier to transition CSSPixels to fixed-point math, one step
we can take is to prevent access to the underlying type using value()
and instead use explicit conversions with the to_float(), to_double(),
and to_int() methods.
Adds a second pass to resolve percentage paddings and margins of grid
items after track sizes are known. If resolving percentage paddings
or margins affects tracks sizes then second pass to re-resolve track
sizes might also be needed but I cannot come up with an example to
reproduce that so we can leave it to improve in the future :)
This fixes the issue when functions that distribute base_size
or growth_limit to tracks only considered *affected* spanned tracks
while calculating left extra that is available for distribution while
indeed it should be just *all* spanned track by specific item that
extra space size.
This changes grid items position storage type from unsigned to signed
integer so it can represent negative offsets and also updates placement
for grid items with specified column to correctly handle negative
offsets.
Fixes the bug that currently we always consider tracks with percentage
size as ones with "fixed" length even when available size is not
definite. With this change tracks with percentage size when available
size is not definite will be considered as "intrinsic" sized.
This fixes a plethora of rounding problems on many websites.
In the future, we may want to replace this with fixed-point arithmetic
(bug #18566) for performance (and consistency with other engines),
but in the meantime this makes the web look a bit better. :^)
There's a lot more things that could be converted to doubles, which
would reduce the amount of casting necessary in this patch.
We can do that incrementally, however.
Using HashTable of grid positions to represent OccupationGrid allows to
simplify positioning code. For example maybe_add_row() and
maybe_add_column() calls are not needed anymore because there is no
Vector<Vector<bool>> that need to be resized.
No observable changes in grid layout are expected :)
Since the specifications indicate that the algorithm for sizing tracks
without any spanning items is a simplified version of the more general
algorithm used for sizing tracks with spanning items, we can reuse the
code to size both cases.
Implements more parts of sizing algorithm for tracks with spanning
items to archive parity with implementation for sizing of tracks
with non-spanning items.
Adds support for grid items with fixed size paddings. Supporting
percentage paddings will probably require to do second pass of tracks
layout: second pass is needed to recalculate tracks sizes when final
items sizes are known when percentage paddings are already resolved.
This change addresses the incorrect assumption that the available width
inside a grid item is equal to the width of the track it belongs to.
For instance, if a grid item has a width of 200px, the available width
inside that item is also 200px regardless of its column(s) base size.
To solve this issue, it was necessary to move the final resolution of
grid items to occur immediately after the final column track sizes are
determined. By doing so, it becomes possible to obtain correct
available width inside grid items while resolving the row track sizes.
This change makes grid items be responsible for their borders instead
of grid tracks which can not have borders itself.
There are changes in layout tests but those are improvements :)
item_incurred_increase should be reset before every next distirbution
because otherwise it will accumulate increases from previous
distributions which is not supposed to happen.
