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.
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.
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 :)
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 :)
This change is supposed to solve the problem that currenty when grid
tracks are interleaved with gaps it is impossible to iterate tracks
spanned by a specific grid item. There is a pair of functions:
gap_adjusted_row() and gap_adjusted_column() but they won't work
when it comes to items spanning > 1 track.
Separating gaps from tracks is going to make it possible to iterate
just tracks or both tracks and gaps when it is required. And now tracks
spanned by an item can be accessed by just index without doing any
additional math.
When a width/height constraint is applied to GFC it should set its own
width/height to the sum of track sizes according to the spec.
Changes in layout tests are improvement over what we had before.
size_t should be used instead of int in loop counter and to store
rows/columns positions because they can't be negative values.
This allows to remove some static casts to int.
1. Stop using -1 to indicate infinity value of growth limit. Just use
INFINITY for that.
2. More complete implementation of "Expand Flexible Tracks" step.
3. Return AvailableSize from get_free_space: spec says that this
function can return indefinite size and it is ok.
Although the algorithm for sizing tracks (rows or columns) is defined
once for both dimensions in the specification
(https://www.w3.org/TR/css-grid-2/#algo-track-sizing), we have
implemented it twice separately for sizing rows and columns.
In addition to code duplication, another issue is that these
implementations of the same algorithm have already diverged in some
places, and this divergence is likely to become even worse as our
implementation evolves.
This change unifies code for both dimension into one method that runs
track sizing.
While this change brings a bit of collateral damange (border.html and
minmax.html got changes in layout snaphots) it ultimately brings more
benefits because now we can evolve layout for both rows and colums
without duplicating the code :)
Instead of special-casing FlexFormattingContext in the intrinsic sizing
layout helpers, add FormattingContext::automatic_content_width() and let
each context subclass decide what that means.
No behavior change here, just moving this responsibility.
This fixes a bug in the CSS Grid when there is a column and/or row gap,
as previously it would take the index of the incorrect column when
finding the `AvailableSize`.
There is a mild complication in the GridFormattingContext as the
OccupationGrid does not take into account the gap columns and rows that
later appear in the `Vector<TemporaryTrack>` columns and rows. The
PositionedBoxes are kind of a connection between the two, and so it's
now more explicit whether you would like to refer to a column by its
position taking into the gap columns/rows or not.
Grid containers were incorrectly represented as BlockContainer before.
Furthermore, GridFormattingContext had a bogus inheritance relationship
with BlockFormattingContext.
This patch brings our architecture closer to spec by making grid
containers be plain boxes and making GFC not inherit from BFC.
If valid grid-template-areas were given, then place grid items within
these areas. Grid-template-areas take precedence over named line
tracks, meaning if there are grid-areas as well as named tracks, should
use the grid-areas.
When starting the GridFormattingContext, calculate the valid grid areas
as declared in the `grid-template-areas` property. Since this doesn't
change, are able to do this once and store the results.
