Also introduce a clear() function to layout data which will be used to clear items such as compositor layouts.
Clear the layout data when a node becomes display:none.
Prior to incremental layout, the code would remove the existing
construction result. However, with incremental layout the construction result
is cloned rather than removed. This change ensures that the previous
construction result is cleared when an element's display type
changes to none.
This patch also makes Servo not crash when
`generated_containing_block_rect()` is called on a list item (as, for
example, GitHub does), and for good measure I added the fix to other
flows as well.
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.
construction to avoid cloning and moving flows so much.
Besides amounting to a 5%-10% win on a page with a lot of text, this
simplifies and refactors the text layout code.
This also adds some extra debugging infrastructure which I found useful tracking
this bug down. A regression in the br reftests is also uncovered by this patch,
which I'll work on fixing next.
r? @pcwalton
This implements fragment merging, in order to incrementally reflow linebroken
text. This makes the `whitespace_pre.html` reftest pass with incremental reflow
turned on with `-i`.
This also hides the not-yet-working parts of incremental reflow behind a runtime
flag. As I get the failing reftests passing, I'll send pull requests for them one
by one.
match L. David Baron's work-in-progress specification.
http://dbaron.org/css/intrinsic/
Column spans are not yet supported.
This effectively adds support for percentage widths, and it also fixes
many bugs, improving the layout of Google and Wikipedia.
matching, and use it for `<input size>` and `<td width>`.
This implements a general framework for legacy presentational attributes
to the DOM and style calculation, so that adding more of them later will
be straightforward.
a separate `ClipDisplayItem`.
We push down clipping areas during absolute position calculation. This
makes display items into a flat list, improving cache locality. It
dramatically simplifies the code all around.
Because we need to push down clip rects even for absolutely-positioned
children of non-absolutely-positioned flows, this patch alters the
parallel traversal to compute absolute positions for
absolutely-positioned children at the same time it computes absolute
positions for other children. This doesn't seem to break anything either
in theory (since the overall order remains correct) or in practice. It
simplifies the parallel traversal code quite a bit.
See the relevant Gecko bug:
https://bugzilla.mozilla.org/show_bug.cgi?id=615734
