This attribute is used to define how the viewBox should be scaled.
Previously the behaviour implemented was that of "xMidYMid meet", now
all of them work (expect none :P).
With this the Discord login backend is now correctly scaled/positioned.
This also brings our SVG code a little closer to the spec! With spec
comments and all :^)
(Minor non-visible update to layout tests)
When sizing a flex container with flex-direction:column under a
max-content height constraint, we were incorrectly truncating the
infinite available height to 0 when collecting flex items into lines.
This caused us to put every flex item in its own flex line, which is the
complete opposite of what we want during max-content intrinsic sizing,
as the layout would grow wide but not tall.
This isn't actually part of CSS-FLEXBOX-1, but all major engines honor
these properties in flex layout, and it's widely used on the web.
There's a bug open against the flexbox spec where fantasai says the
algorithm will be updated in CSS-FLEXBOX-2:
https://github.com/w3c/csswg-drafts/issues/2336
I've added comments to all the places where we adjust calculations for
gaps with "CSS-FLEXBOX-2" so we can find them easily. When that spec
becomes available, we can add proper spec links.
Log a FIXME on the debug log, along with a layout tree dump of the box
that we didn't expect to see. This will be annoying (until fixed),
but far less so than crashing the browser.
This also combines the viewbox mapping into the same transform and
reuses some code by using Path::copy_transformed() rather than manually
mapping each segment of the path.
Previously, if you had an SVG with a viewbox and a definite width
and height, then all SVGGeometryBox boxes within that SVG would
have a width and height set to the size of the parent SVG.
This broke hit testing for SVG paths, and didn't make much sense.
It seems like the SVG sizing hack was patching over the incorrect
logic in viewbox_scaling() and the incorrect path sizing (which was
never reached).
Before this change the view box scaling was:
element_dimension / viewbox_dimension
Which only seemed to work because of the SVG sizing hack that made
all paths the size of the containing SVG.
After this change SVGGeometryBoxes are (in most cases) sized correctly
based on their bounding boxes, which allows hit testing to function,
and the view box scaling is updated now to:
containing_SVG_dimension / viewbox_dimension
Which works with one less hack :^)
This now also handles centering the viewbox within the parent SVG
element and applying any tranforms to the bounding box. This still
a bit ad-hoc, but much more closely matches other browsers now.
Grid and flex containers have their own rules for abspos items, so we
shouldn't try to be clever and put them in the "current" anonymous
wrapper block. That behavior is primarily for the benefit of block &
inline layout.
When calculating the intrinsic width of a block-level box, we now ignore
the preferred width entirely, and not just when the preferred width
should be treated as auto.
The condition for this was both confused and wrong, as it looked at the
available width around the box, but didn't check for a width constraint
on the box itself.
Just because the available width has an intrinsic sizing constraint
doesn't mean that the box is undergoing intrinsic sizing. It could also
be the box's containing block!
This parses the new background-position-x/y longhands and properly
hooks up them up. This requires converting PositionStyleValue to
just contain two EdgeStyleValues so that it can be easily expanded
into the longhands.
In situations where we need a width to calculate the intrinsic height of
a flex item, we use the fit-content width as a stand-in. However, we
also need to clamp it to any min-width and max-width properties present.
In `flex-direction: column` layouts, a flex item's intrinsic height may
depend on its width, but the width is calculated *after* the intrinsic
height is required.
Unfortunately, the specification doesn't tell us exactly what to do here
(missing inputs to intrinsic sizing is a common problem) so we take the
solution that flexbox applies in 9.2.3.C and apply it to all intrinsic
height calculations within FlexFormattingContext: if the used width of
an item is not yet known when its intrinsic height is requested, we
substitute the fit-content width instead.
Note that while this is technically ad-hoc, it's basically extrapolating
the spec's suggestion in one specific case and using it in all cases.
When calculating the intrinsic width of a box, we now make its content
width & height indefinite before entering the intrinsic sizing layout.
This ensures that any geometry assigned to the box by its parent
formatting context is ignored.
For intrinsic heights, we only make the content height indefinite.
This is because used content width is a valid (but optional) input
to intrinsic height calculation.
The "flex item automatic minimum size in the main axis is the
content-based minimum size" behavior should only apply to flex item
sizes in the main axis. There was one case where we incorrectly applied
this behavior in the cross axis
The "flex item automatic minimum size in the main axis is the
content-based minimum size" behavior should only apply to flex items
that aren't scroll containers. We were doing it for all flex items.
When calculating one of the intrinsic sizes for a flex container, we
already go through the flex layout algorithm.
There's no need to perform some of the algorithm steps a second time.
This is a relic from an earlier time when we tried to bail early from
the layout algorithm in the intrinsic sizing case. Now that we go
through the whole thing anyway, this is much simpler. :^)
Negative width/height sizes are not allowed in CSS, so if our layout
algorithm resolves something to a negative size, we have boogs.
Instead of crashing or rendering something very wrong, we now clamp the
values to 0 and whine on the debug log so that someone can go and figure
out how we got the negative values in the first place. :^)
If the previous sibling of an out-of-flow box has been wrapped in an
anonymous block, we now stuff the out-of-flow box into the anonymous
block as well.
Co-authored-by: Aliaksandr Kalenik <kalenik.aliaksandr@gmail.com>
