Unify background placement code
Merges the implementations for background-image placement
from gradients and images. Add missing parts and fix bugs.
Now supported are the CSS properties:
* background-attachment (except for local value, see #19650)
* background-clip
* background-origin
* background-position-x/y
* background-repeat
* background-size
It should be noted that backgrounds are not clipped to
rounded border corners.
(This was done before but worked only in simple cases)
See: #19649
This solves the following issues:
closes#19626closes#16657closes#19482 (examples from http://lea.verou.me/css3patterns/ are rendered perfectly but the round border is completely ignored now)
closes#19577
- `./mach build -d` does not report any errors
- `./mach test-tidy` does not report any errors
I enabled a few tests with the first commit but I have written about a dozen manual tests I will try to turn into ref tests either before or after this patch lands.
@bors-servo try
The relationship between the different inputs is visualized in this flowchart:

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Merges the implementations for background-image placement
from gradients and images. Add missing parts and fix bugs.
Now supported are the CSS properties:
* background-attachment (except for local value)
* background-clip
* background-origin
* background-position-x/y
* background-repeat
* background-size
It should be noted that backgrounds are not clipped to
rounded border corners.
DOMMatrix needs to convert a specified transform list into a matrix, so
we could rewrite to_transform_3d_matrix by generics for both specified
and computed transform lists.
Besides, we have to update the test case because we use Transform3D<f64> to
compute the matrix, instead of Transform3D<f32>, so the result will be
the same as that in Gecko. Using 0.3 may cause floating point issue
because (0.3f32 as f64) is not equal to 0.3 (i.e. floating point precision
issue), so using 0.25 instead.
Use try syntax for Option where appropriate
- [x] `./mach build -d` does not report any errors
- [x] `./mach test-tidy` does not report any errors
- [x] These changes do not require tests because they are refactoring only
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We replace Au with CSSPixelLength for the length part of
computed::CalcLengthOrPercentage. Therefore, it would be easier to use
CSSPixelLength for all other LengthOrPercentage{*} types.
First, we define computed::CSSPixelLength which contains a CSSFloat, a
pixel value, and then we replace computed::Length with CSSPixelLength.
Therefore, the |ComputedValue| of NoCalcLength, AbsoluteLength,
FontRelativeLength, ViewportPercentageLength, CharacterWidth, and
PhysicalLength is CSSPixelLength.
Besides, we drop NonNegativeAu, and replace computed::NonNegativeLength
with NonNegative<computed::Length>. (i.e. NonNegative<CSSPixelLength>)
Add support for position:sticky
This leverages the position:sticky support in WebRender to bring basic
support for position:sticky in Servo. There are still some issues with
nested sticky flows as well as a few other corner cases. Tests are
imported from WPT and can be removed once we update to the latest
version.
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This leverages the position:sticky support in WebRender to bring basic
support for position:sticky in Servo. There are still some issues with
nested sticky flows as well as a few other corner cases. Tests are
imported from WPT and can be removed once we update to the latest
version.
stylo: Bug 1390039 - Implement compute_distance for mismatched transform lists.
Implement ComputeSquaredDistance for mismatched transform lists.
In order to do this, we have to convert a transform list into a 3d matrix,
so I move the code from layout module into style module for reusing it.
---
- [X] `./mach build -d` does not report any errors
- [X] `./mach test-tidy` does not report any errors
- [X] These changes fix [Bug 1390039](https://bugzilla.mozilla.org/show_bug.cgi?id=1390039).
- [X] These changes do not require tests because this is a Gecko feature and I add many tests in Gecko already.
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We could use this method to convert a TransformList into a Matrix, and
use this matrix for computing distance for Stylo and rendering the transform
for Servo.
This is an equivalent of nsStyleTransformMatrix::ReadTransforms in Gecko.
Fix the long-standing bug where items that are positioned and have
overflow:scroll or overflow:auto automatically create stacking
contexts. In order to do this we need to fix another bug where display
list sorting can put a Clip or ScrollFrame definition after the first
time it is used in a display list.
Instead of only promoting flows with positioned fragments to containing
blocks, also do this for flows which have the transform, perspective or
filter properties set. This is what the spec requires and also fixes
some failing tests. It will allow us to stop creating stacking contexts
for overflow:hidden and overflow:scroll flows.
Fixes#18091.
According to the spec, the computed value of transform is as specified, but
with relative lengths converted into absolute lengths, so in Gecko, we do
nothing while computing the value of rotate3d(), and do normalization in
ProcessRotate3D(). If the direction cannot be normalized, we treat it as
an identity matrix.
However, in Servo, we do normalization in to_computed_value(), and looks
like we are trying to normalize any kind of direction vectors, so according
to the spec, let's move the normalization into Fragment::transform_matrix(),
and return an identity matrix if we cannot normalize its direction vector.
Add values::computed::NonNegativeAu, so BorderSideWith could be computed
to this non-negative Au, for the following properties:
1. outline-width
2. border-{*}-width
3. column-rule-width
4. -webkit-text-stroke-width
MozReview-Commit-ID: ASHaB2F7VtM
The alias is left there temporarilly and will be removed completely in a later commit where
also components/style/gecko/generated/structs_{debug|release}.rs are re-generated (they still
use the old alias).
Previously the variable names were a little confusing (ascent was used
for the space_above_baseline in one branch and the and ascent field in
another branch, and was not really the ascent in one). Also add a
small diagram.
If we set the composite operation to accumulate, we may need to accumulate two
mismatched transform lists, and then to interpolate them. In order to
accumulate two mismatched transform lists, we also need the reference
box information, so use the same idea as that for interpolation. i.e.
use AccmulateMatrix to store it temporarily, and convert it into matrix
later.
We use this arm to store the interpolated result of two mismatched
transform lists, and we resolve it until we know the reference box size
(on Gecko side). The conversion from ComputedOperation::InterpolateMatrix
to eCSSKeyword_interpolatematrix will be implemented later in this patch series.
Make canvas origin clean checks use origin of image response
Adapted from #15887.
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- [X] `./mach build -d` does not report any errors
- [X] `./mach test-tidy` does not report any errors
- [X] These changes fix#15409
- [X] There are tests for these changes
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