Add initial support for transforms to layout_2020
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Add initial support for stacking contexts to layout_2020
These changes add initial support for stacking contexts, enabling some parts of z-index to work properly.
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This adds very rudimentary support for paint order in stacking context.
In particular z-index is now handled properly, apart from issues with
hoisted fragments.
It's not possible anymore, in the presence of min() / max(), to split a
<length-percentage> value into a <length> and a <percentage> component.
Tweak word_spacing to do what Gecko does (resolving it in advance).
For now, we still bail out at the stage of getting the calc node into a
CalcLengthPercentage if we couldn't simplify the min() / max() / clamps()
involved.
After this plan is to use just CalcNode everywhere instead of
specified::CalcLengthPercentage, and then modify the computed
CalcLengthPercentage, which would look slightly different as we know all the sum
terms for those are a struct like { Length, Percentage, bool has_percentage } or
such, so all the simplification code for that becomes much simpler, ideally.
Or we could turn CalcNode generic otherwise, if it's too much code... We'll see.
Differential Revision: https://phabricator.services.mozilla.com/D61739
There were two issues with the existing code that we use to determine whether a
widget is styled or not.
First, it was using `color == Color::transparent()` instead of
`color.is_transparent()` to check for transparent backgrounds. That is not sound
as `Color::transparent()` is the literal value `rgba(0, 0, 0, 0)`, not the
`transparent` keyword, so the equality check would fail.
The other issue is that this function was early-returning false if that check
was returning false. It is a bug for this function to early-return false, as it
makes the result of the function dependent of the order of the declarations.
Differential Revision: https://phabricator.services.mozilla.com/D62060
This removes nsStyleImageRequest by moving the load state to LoadData instead
(where other lazy state like the resolved URL and load id lives).
That way we can use cbindgen for more stuff (there's no blocker for using it for
all images now), and we can undo the image tracking shenanigans that I had to do
in bug 1605803 in nsImageFrame.
This removes the mDocGroup member because well, there's no real upside of that
now that quantum DOM is not a thing.
It also removes the static clones of the image requests, and the need for each
computed value instance to have its own request. These were needed because we
needed the image loader for the particular document to observe the image
changes. But we were also tracking the request -> loader for other purposes.
Instead, Now all the images get loaded with GlobalImageObserver as a listener,
which looks in the image map and forwards the notification to all the interested
loaders instead dynamically.
The style value is only responsible to load the image, and no longer tracks /
locks it. Instead, the loader does so, via the image tracker.
Differential Revision: https://phabricator.services.mozilla.com/D58519
Keep a flat list of sum members. Simpify product and division ASAP.
I want to preserve the tree for a bit longer to implement min / max / clamp.
This doesn't do anything for it that we weren't doing already, but it helps to
eventually keep this specified representation and the equivalent computed
representation for <length-percentage> values.
Enable the tests for the comparison functions too, to prevent regressions.
Differential Revision: https://phabricator.services.mozilla.com/D61514
We're resetting `color` to the default color when there's a declaration that
applies in order to make stuff like this:
<div style="color: transparent">
<div style="color: red">
Red
</div>
</div>
To not show transparent. But the behavior we want is more like "override with
default color iff there's no other declaration that would set the color from an
user or UA sheet".
This implements that behavior, plus avoids it if we're not inheriting
from transparent, so that stuff like this preserves the behavior from before bug
844349:
<a href="foo">
<span style="color: red">Should be the red color</span>
</a>
Differential Revision: https://phabricator.services.mozilla.com/D60391
Per SVG2 spec, the EBNF allows the path data string to be empty.
An empty path data string disables rendering of the path.
Therefore, we should make path('') a valid path string.
The related spec issue: https://github.com/w3c/fxtf-drafts/issues/392.
Now we serialize `path("")` as `path("")` for offset-path and clip-path.
Differential Revision: https://phabricator.services.mozilla.com/D60771
This simplifies a bit the code, and guarantees that all calc()s have percentages
and lengths.
I also wanted to remove unclamped_length() / specified_percentage() (for the
same reason as the above patch), but they're needed for animations for now. When
I implement min() / max() for <length-percentage> they'll be fixed.
Differential Revision: https://phabricator.services.mozilla.com/D60194
This is just not a thing you can do if you have min() / max() / etc, as the min
/ max value may depend on the percentage basis.
Differential Revision: https://phabricator.services.mozilla.com/D60168
It does not make any sense with min() / max() / clamp. So just forget the
keyword info when calc() is used. This also removes a bit of complex / hacky
code.
Differential Revision: https://phabricator.services.mozilla.com/D60663