I've done a bit of job to get this done. Right now readback is still used, but we have a `LayerId` -> `CanvasRenderer` map on the paint task, that we can use to get rid of that.
I'd want review, to see if this is a good approach (I know it's not the initial `CanvasId` -> renderer approach, but it's pretty similar, since a canvas involves a `PaintLayer`).
I had to do a bit of refactoring to avoid cyclic dependencies between canvas and gfx. I'd want you to review them too.
It's mergeable and doesn't break any tests :P
Some of my main concerns:
* Does the canvas render really need to be behind an `Arc<Mutex<T>>`?
* I can't clone a `NativeSurface` right now (that's why the `SendNativeSurface()` msg is unimplemented in the WebGL task). It should be easy to add that to rust-layers, supposing the caller is responsible to mark it as non-leaking, any reason to not do it?
cc @jdm @pcwalton
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The basic idea is it's safe to output an image for reftest by testing:
- That the compositor doesn't have any animations active.
- That the compositor is not waiting on any outstanding paint messages to arrive.
- That the script tasks are "idle" and therefore won't cause reflow.
- This currently means page loaded, onload fired, reftest-wait not active, first reflow triggered.
- It could easily be expanded to handle pending timers etc.
- That the "epoch" that the layout tasks have last laid out after script went idle, is reflected by the compositor in all visible layers for that pipeline.
Spec: http://dev.w3.org/csswg/css-device-adapt/
Currently, the actual viewport is used by the layout task as part of the reflow, and the compositor uses the zoom constraints. I'm not sure if anywhere else currently needs access to the constraints (i.e. there's no CSSOM as far as I can tell).
I did not implement sections 9 (viewport <META>) or 10 (handling 'auto' for 'zoom').
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A rebuild after touching components/profile/mem.rs now takes 48 seconds (and
only rebuilds `profile` and `servo`) which is much lower than it used to be.
In comparison, a rebuild after touching components/profile_traits/mem.rs takes
294 seconds and rebuilds many more crates.
This change also removes some unnecessary crate dependencies in `net` and
`net_traits`.
Some debugging reveals that the send_back_unused_buffers() quite often
sends empty vectors back to the paint task. This still incurs an
communication overhead though. Instead check that the there actually are
buffers to send back.
Transition events are not yet supported, and the only animatable
properties are `top`, `right`, `bottom`, and `left`. However, all other
features of transitions are supported. There are no automated tests at
present because I'm not sure how best to test it, but three manual tests
are included.
- Most of util::memory has been moved into profile::mem, though the
`SizeOf` trait and related things remain in util::memory. The
`SystemMemoryReporter` code is now in a submodule
profile::mem::system_reporter.
- util::time has been moved entirely into profile::time.
This fixes#5234, in that the huge memory spike disappears. It still takes ~15 seconds for the window to actually disappear after that first `Quit` event is received by the IOCompositor. Maybe that's a pre-existing problem.
There may be better ways to do this, like handling it on the sending side (i.e. within glutin) instead of the receiving side. I just did it this way because it seemed like the easiest thing.
This changeset implements the beginnings of fine-grained measurement of
Servo's data structures.
- It adds a new `SizeOf` trait, which is used to measure the memory used
by heap data structures, and implements it for some std types: Box,
String, Option, Arc, Vec, and DList.
- It adds a new `MemoryReporter` trait which is used to report memory
measurements from other threads to the memory profiler. Reporters are
registered and unregistered with the memory profiler, and the memory
profiler makes measurement requests of reporters when necessary.
- It plumbs a MemoryProfilerChan through to the layout task so it can
register a memory reporter.
- It implements the `SizeOf` trait for `DisplayList` and associated
types, and adds a memory reporter that uses it.
The display list hits 14.77 MiB when viewing
tests/html/perf-rainbow.html, and 2.51 MiB when viewing the Guardians of
the Galaxy Wikipedia page from servo-static-suite. Example output:
0.29: display-list::http://www.reddit.com/
0.00: display-list::http://static.adzerk.net/reddit/ads.html?sr=-reddit.com,loggedout&bust2#http://www.reddit.com
0.00: display-list::http://www.reddit.com/static/createadframe.html
There are a number of FIXME comments indicating sub-optimal things. This
is a big enough change for now that doing them as follow-ups seems best.
The history is now recorded per frame, but needs to be exposed in a followup PR.
Also fixes a race condition that occurs loading iframes under heavy CPU load.
This ensures that iframes never do a reflow / layout until they have a valid
window size set from their parent frame.
If the root layer has a zero size rectangle, it will never be
painted, so assume the pipeline is idle in that case.
Re-enable two reftests that were disabled due to this issue.
Sometimes, the root pipeline title is sent before the compositor has created the root pipeline, so also request the main page title once the initial frame tree has been sent.
When an iframe is created with display:none it sets the root layer to be
zero width and height. When updating the rect of the iframe from layout
send the entire rect rather than just the new origin, which handles the case
where the iframe has been made visible and now has a non-zero rect.
Sometimes, the root pipeline title is sent before the compositor
has created the root pipeline, so also request the main page
title once the initial frame tree has been sent.
