`background-size` per CSS-BACKGROUNDS § 3.9.
Nearest neighbor interpolation is used for `crisp-edges`, like Firefox.
A note has been added that we could do better if we wanted to.
Multiple backgrounds are not yet supported.
Rebase of #4368. Fixes#4368.
Only simple alphabetic and numeric counter styles are supported. (This
is most of them though.)
Although this PR adds a sequential pass to layout, I verified that on
pages that contain a reasonable number of ordered lists (Reddit
`/r/rust`), the time spent in generated content resolution is dwarfed by
the time spent in the parallelizable parts of layout. So I don't expect
this to negatively affect our parallelism expect perhaps in pathological
cases.
Moved from #4544, because Critic.
Fixes#4544.
`background-size` per CSS-BACKGROUNDS § 3.9.
Nearest neighbor interpolation is used for `crisp-edges`, like Firefox.
A note has been added that we could do better if we wanted to.
Multiple backgrounds are not yet supported.
§ 12.3-12.5.
Only simple alphabetic and numeric counter styles are supported. (This
is most of them though.)
Although this PR adds a sequential pass to layout, I verified that on
pages that contain a reasonable number of ordered lists (Reddit
`/r/rust`), the time spent in generated content resolution is dwarfed by
the time spent in the parallelizable parts of layout. So I don't expect
this to negatively affect our parallelism expect perhaps in pathological
cases.
Move culling of transparent display items to paint task rather than display list builder, so that hit testing detects mouse over on transparent background elements.
Conforming to section 5.5 (Rounded Corners/Overlapping Curves) of "CSS
Background and Borders Module Level 3", border radii on elements whose
border curves would have overlapped are uniformly scaled down to the
point that they no longer do.
http://dev.w3.org/csswg/css-backgrounds/#corner-overlap
through display list building.
The old `flow_origin` concept was ill-defined (sometimes the border box
plus the flow origin, sometimes including horizontal margins and
sometimes not, sometimes including relative position and sometimes not),
leading to brittleness and test failures. This commit reworks the logic
to always pass border box origins in during display list building.
The exact rendering is ill-spec'd. Some things are ugly (especially the
width and height of list style images) but they are infrequently used
and I believe this implementation matches the spec. Numeric lists are
not supported yet, since they will require a separate layout pass.
The implementation is a subclass of `BlockFlow`, on advice from Robert
O'Callahan.
`invert` is not yet supported.
Objects that get layers will not yet display outlines properly. This is
because our overflow calculation doesn't take styles into account and
because layers are always anchored to the top left of the border box.
Since fixing this is work that is not related to outline *per se* I'm
leaving that to a followup and making a note in the code.
This adds the infrastructure necessary to support stacking contexts that
are not containing blocks for absolutely-positioned elements. Our
infrastructure did not support that before. This minor revamp actually
ended up simplifying the logic around display list building and
stacking-relative position computation for absolutely-positioned flows,
which was nice.
This patch is a first stab at implementing border-radius. It looks fine as long as
the border isn't an ellipse (that might not even parse yet), and the border-widths
around a border-radius are the same.
Here's a cool screenshot!

r? @pcwalton @SimonSapin