This implements the scheme described here:
https://groups.google.com/forum/#!topic/mozilla.dev.servo/sZVPSfPVfkg
This commit changes Servo to generate one display list per stacking
context instead of one display list per layer. This is purely a
refactoring; there are no functional changes. Performance is essentially
the same as before. However, there should be numerous future benefits
that this is intended to allow for:
* It makes the code simpler to understand because the "new layer needed"
vs. "no new layer needed" code paths are more consolidated.
* It makes it easy to support CSS properties that did not fit into our
previous flat display list model (without unconditionally layerizing
them):
o `opacity` should be easy to support because the stacking context
provides the higher-level grouping of display items to which opacity
is to be applied.
o `transform` can be easily supported because the stacking context
provides a place to stash the transformation matrix. This has the side
benefit of nicely separating the transformation matrix from the
clipping regions.
* The `flatten` logic is now O(1) instead of O(n) and now only needs to
be invoked for pseudo-stacking contexts (right now: just floats),
instead of for every stacking context.
* Layers are now a proper tree instead of a flat list as far as layout
is concerned, bringing us closer to a production-quality
compositing/layers framework.
* This commit opens the door to incremental display list construction at
the level of stacking contexts.
Future performance improvements could come from optimizing allocation of
display list items, and, of course, incremental display list
construction.
r? @glennw
f? @mrobinson @cgaebel
Source-Repo: https://github.com/servo/servo
Source-Revision: 397d8138e7b27541faf03d9635d7648416da4a75
Instead of looking at the display tree, have ContentBox(es)Query consult
the flow tree. This allow optimizing away parts of the display tree
later. To do this we need to be more careful about how we send reflow
requests, only querying the flow tree when possible.
Fixes#3790.
Source-Repo: https://github.com/servo/servo
Source-Revision: c9089c45c4b7d40419233b48a192d85a8ad71c99
This is the last PR and most of the work for the maze solver and RoboHornet.
r? @glennw
cc @cgaebel
Source-Repo: https://github.com/servo/servo
Source-Revision: 035ff19e4a5995989c5fd34928af2a6690bb8062
`layout::fragment` and `layout::block` were getting too big.
r? @mrobinson
Source-Repo: https://github.com/servo/servo
Source-Revision: 01f6a8102dfbb7eaef564acf8891088011905b59
r? @pcwalton
Looks like I forgot to save `ScannedTextFragment`s block sizes with their
inline sizes. This patch fixes that.
Fixes#3753
Source-Repo: https://github.com/servo/servo
Source-Revision: fe230ef37deaed2d6631af58ab923db023dcf319
This is quite a bit cleaner than abusing the rust debug functionality.
If we start collecting too many debugging options in the servo
executable we could opt to organize them into a single option.
Fixes#2263.
Source-Repo: https://github.com/servo/servo
Source-Revision: 3936d142607ef5a9b4a49d48e207daf4975cc7d5
This is a grab bag of performance improvements that significantly improve style recalculation, layout, and painting on a few static pages.
Let me know if you'd like me to split this PR up.
r? @glennw
Source-Repo: https://github.com/servo/servo
Source-Revision: 156ca98236a57ee52ff5b68741bc7783ba073612
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.
EDIT: nevermind. no regression, I just tested that before a rebase.
r? @pcwalton
Source-Repo: https://github.com/servo/servo
Source-Revision: b86344b697f814b982e52f4a72c26d58c915c37b
Seems to be a 38% layout win on a site I tested with a lot of text.
Other browser engines typically do not duplicate the information in the font style struct. `FontStyle` actually predates @SimonSapin's CSS selector matching library. It's time to get rid of it!
r? @glennw
Source-Repo: https://github.com/servo/servo
Source-Revision: 83196ddb26b5611bccfa2d709396daeff259bcd1
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`.
Source-Repo: https://github.com/servo/servo
Source-Revision: f3066c70da80306f68833814025deb589d6eeb2a
This patch switches FlowRefs to using the Deref and DerefMut traits, instead of
the custom `get` and `get_mut` functions.
Source-Repo: https://github.com/servo/servo
Source-Revision: 6a11ee89de82abae9d6607a6c2890692df5259eb
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.
r? @SimonSapin
Source-Repo: https://github.com/servo/servo
Source-Revision: e2d7777c41135b71293c195d2a9d7a1bc2afd0ca
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.
Source-Repo: https://github.com/servo/servo
Source-Revision: 0aeecfc41d5f0c637960fcddf87cc2db3e5efeea
75% improvement in style recalc for Guardians of the Galaxy.
Source-Repo: https://github.com/servo/servo
Source-Revision: 8077edc0622b04aeb26d42ced86ea285c9cac0e7
Instead of taking margin size into account twice when positioning
layers, just rely on the absolute position calculated during display
list construction.
Source-Repo: https://github.com/servo/servo
Source-Revision: 834df4e211e7dcac4369da4f5b8113f295869aa1
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
r? @mrobinson
Source-Repo: https://github.com/servo/servo
Source-Revision: fd70b366aeada7f8cb4b2457c04fd07f0ea9b143
This makes layout more idempotent, which is important for incremental
layout.
Also converts `is_root` to a set of flags and fixes a `TODO` concerning
percentage inline heights of images.
r? @glennw
Source-Repo: https://github.com/servo/servo
Source-Revision: 7902ccf8507a7ec31515bfb5824dc4727564fe4d
This patch puts in the initial framework for incremental reflow. Nodes' styles
are no longer recalculated unless the node has changed.
I've been hacking on the general problem of incremental reflow for the past
couple weeks, and I've yet to get a full implementation that actually passes all
the reftests + wikipedia + cnn. Therefore, I'm going to try to land the different
parts of it one by one.
This patch only does incremental style recalc, without incremental flow
construction, inline-size bubbling, reflow, or display lists. Those will be coming
in that order as I finish them.
At least with this strategy, I can land a working version of incremental reflow,
even if not yet complete.
r? @pcwalton
Source-Repo: https://github.com/servo/servo
Source-Revision: 85b277655f07db1cb99c4d3dee93804735ed0470
The Mach test runner doesn't actually make these failures yet, which is
tracked by #3482.
Source-Repo: https://github.com/servo/servo
Source-Revision: ae946a9b762d66f01f669ff526eff5c0eaaa3404
Although the computed `display` property of elements with `position:
absolute` is `block`, `position: absolute; display: inline` can still
behave differently from `position: absolute; display: block`. This is
because the hypothetical box for `position: absolute` can be at the
position it would have been if it had `display: inline`. CSS 2.1 §
10.3.7 describes this case in a parenthetical:
"The static-position containing block is the containing block of a
hypothetical box that would have been the first box of the element if
its specified 'position' value had been 'static' and its specified
'float' had been 'none'. (Note that due to the rules in section 9.7 this
hypothetical calculation might require also assuming a different
computed value for 'display'.)"
To handle this, I had to change both style computation and layout. For
the former, I added an internal property
`-servo-display-for-hypothetical-box`, which stores the `display` value
supplied by the author, before the computed value is calculated. Flow
construction now uses this value.
As for layout, implementing the proper behavior is tricky because the
position of an inline fragment in the inline direction cannot be
determined until height assignment, which is a parallelism hazard
because in parallel layout widths are computed before heights. However,
in this particular case we can avoid the parallelism hazard because the
inline direction of a hypothetical box only affects the layout if an
absolutely-positioned element is unconstrained in the inline direction.
Therefore, we can just lay out such absolutely-positioned elements with
a bogus inline position and fix it up once the true inline position of
the hypothetical box is computed. The name for this fix-up process is
"late computation of inline position" (and the corresponding fix-up for
the block position is called "late computation of block position").
This improves the header on /r/rust.
r? @glennw
Source-Repo: https://github.com/servo/servo
Source-Revision: f7d2fb6ff86afff7a5b674f751af9370a5a6b142
So far the changes to layout seem fairly well-contained; I think this is worth integrating to give us a browser that is easier to dogfood (and allows us to work on things like form submission much easier), especially since the long-term viability of WebComponents-as-forms is not assured.
Source-Repo: https://github.com/servo/servo
Source-Revision: f80096069592b864221abe112eaf2ecb6c444fda
