layers in the fragment, so that it can be activated when we're forcing
the creation of extra layers due to positioned descendants that
themselves have layers.
The newly failing tests were tests that accidentally passed due to
incorrect stacking order.
Closes#7281.
Known issues:
* Display list optimization can sometimes optimize out elements that
should be shown. This affects the Enyo demo.
* The `overflow: scroll` container doesn't clip the inner layer properly
when borders, border radius, etc. are present.
* `overflow-x: scroll` and `overflow-y: scroll` don't work individually;
elements are scrolled all at once.
* Scrolling only works on absolutely-positioned elements.
At this point the only thing it does is to try to avoid adding display
items that are outside the root scrollable area, which is both wrong
(since it's incompatible with having scrollable areas outside the root)
and is useless (because we have displayports now).
To actually make the multiprocess communication work, we'll need to
reroute the task creation to the pipeline or the compositor. But this
works as a first step.
The idea here is to land this before making images and canvas IPC-safe,
because this will shake out bugs relating to the shared memory. There
are currently test timeouts that are preventing multiprocess images and
canvas from landing, and I believe those are due to the inefficiency of
sending large amounts of data in the unoptimized builds we test with. By
moving to shared memory, this should drastically reduce the number of
copies and `serde` serialization.
Under the hood, this uses Mach OOL messages on Mac and temporary
memory-mapped files on Linux.
This commit introduces the `serde` dependency, which we will use to
serialize messages going between processes in multiprocess Servo.
This also adds a new debugging flag, `-Z print-display-list-json`,
allowing the output of display list serialization to be visualized.
This will be useful for our experiments with alternate rasterizers.
* Add parser support for 3d transforms.
* Change ComputedMatrix to a representation that suits interpolation.
* Switch stacking contexts to use 4x4 matrices.
The transforms themselves are still converted to 2d and handled by azure for now, but this is a small standalone part that can be landed now to make it easier to review.
image fragments.
This also changes the way the placeholder is handled in the image cache
task to decode it up front instead of each time an image fails to load,
both because it was more convenient to implement that way and because
it saves CPU cycles to do so.
This matches the behavior of Gecko and WebKit. It improves the look of
our cached copy of Wikipedia.
This property determines the background positioning area, that is the position of
the origin of an image specified using the 'background-image' CSS property.
'background-origin' is ignored when background-attachment is fixed.
Spec: http://dev.w3.org/csswg/css-backgrounds-3/#background-originFixes#6045.
absolutely-positioned elements.
This also implements a little bit of the infrastructure needed to
support for fragmentation via support for multiple positioned fragments
in one flow.
Improves Google.
* Fix queries involving stacking contexts
* The code was double accumulating stacking context origins.
* Handle queries of inline elements.
* The node addresses being compared were incorrect (CharacterData vs. Span)
* Handle ScriptQuery reflows correctly.
* The layout task was skipping the compute absolute positions traversal, so failed before window.onload.
Known issues:
* Collapsed borders do not correctly affect the border-box of the table
itself.
* The content widths of all cells in a column and the content height of
all cells in a row is the same in this patch, but not in Gecko and
WebKit.
* Corners are not painted well. The spec does not say what to do here.
* Column spans are not handled well. The spec does not say what to do
here either.
It required to move create_stacking_context() outside of BlockFlow,
as a method of FragmentDisplayListBuilding. This allowed the reuse
for inline fragments that need a stacking context.
As we now create stacking contexts (SC) for inline elements, this stresses
the code in Fragment that calculates the need for a SC.
For while, we create a SC only if there are filters associated with the
Inline element. Companion issue is #5812.
