style: Slim down SharedStyleContext, and do various other cleanups around the style crate.
This slims down SharedStyleContext, in preparation for a few things.
First, I would like to eventually move the stylist to the document in Servo, in
order for it to hold the StyleSheetSet.
Also, this gets rid of a fair amount of overhead while creating it in stylo.
Fixes bug 1363245.
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This slims down SharedStyleContext, in preparation for a few things.
First, I would like to eventually move the stylist to the document in Servo, in
order for it to hold the StyleSheetSet.
Also, this gets rid of a fair amount of overhead while creating it in stylo.
Fixes bug 1363245.
A specified position is now a struct made of two values of different types,
the first one being PositionComponent<X>, and the second one PositionComponent<Y>.
A position component is represented by the new enum PositionComponent<Side>,
with the three values Center, Length(LengthOrPercentage), and
Side(Side, Option<LengthOrPercentage>).
Side keywords are represented by the X and Y enums, which don't include a value
for the center keyword anymore. They are accompanied by the Side trait, which
allows us to determine whether a side keyword is "left" or "top".
This refactor simplified the parsing and serialisation code and exposed bugs in it,
where it would reject valid <position> values followed by arbitrary tokens,
and where it would fail to prefer "left" to "right" when serialising positions
in basic shapes.
There are situations where elements are transformed from outside the
display list. With projective transforms it's currently difficult to
detect these. In those cases we just don't optimize the display list,
so that they will always be shown.
Fixes#13822.
bump required rayon version to 0.7
...and bring jpeg-decoder along for the ride. Minor tweaks were necessary because of rayon API changes.
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Improvements to gradients.
This is a collection of commits improving the rendering of linear and radial gradients by making them conform more closely to the spec.
All commits are are independent and should work without the others.
These commits address the following issues:
* a956e3fd52resolves#3908 but contains also some other necessary changes to `convert_gradient_stops`. The updated function has a few more copys but should be more correct. Maybe @pcwalton wants to comment since he has originally written the code.
* b230be8aaf partially solves #16638. (Partially because `border-image-outset` is not implemented. This is an older issue for border gradients: #15894.
To quickly catch regressions and see changes to gradients I have created [a set of twelve manual testcases](https://pyfisch.org/stuff/testcases-gradients.html) and placed them in a single file. Attached are two files. One shows how the gradients were rendered before the PR the other one with the changes applied.


r? @emilio
and maybe also @jdm?
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If the first stop of a non-repeating gradient is
not placed at offset 0.0 it is duplicated at this
position. This solves the problem of the first
stop being ignored if it is placed at the same
offset as the next stop.
Implement Specification from CSS Images 3.
Improvements:
1. Stops with positions less than preceding stops are moved.
A common pattern is blue `70%, white 0` for sharp transitions.
2. Stop runs are correct if first stop has a position.
The list `black 0%, red, gold` now renders the same as `black, red, gold`.
Other runs may also be corrected.
3. Absolute length are no longer capped to 100%.
Implement radial gradients
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This PR passes the `radial-gradient` function down from CSS parsed properties to webrender. It currently lacks tests but the examples from MDN and some other tests work fine. Probably there are some wpt tests I can enable?
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stylo: support all overflow values
overflow:clip doesn't exist, it's just called clip internally. Renamed, and added the other missing values.
I also removed the overflow newtype -- no need for extra code bloat, and it's not protecting us from much.
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Add calc method for CalcLengthOrPercentage
* Add calc method to calculate formula value with parent size
* Add unit test case
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Please see this issue: https://github.com/servo/servo/issues/15986
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* Add to_computed method to calculate `calc()` value with parent size,
if parent container size is `None`, the result will be `None`.
* Add from_option method for `MaybeAuto`, to construct from
`Option<Au>`.
* Update some test case.
layout: Force reflow in the sequential fallback of block format context
When reflowing a block format context during the inorder traversal,
propagate restyle damage manually to its children since they were
already reflowed. Also, test the border box to see if it can fit into
floats according to CSS 2.1 § 9.5.
Improves reddit and yahoo.
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