Don't promote all scrollable regions to stacking contexts
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Don't promote all scrollable regions to stacking contexts
Instead annotate all flows with their owning ScrollRoots. When
processing the display list items into a flattened display list, we add
PushScrollRoot and PopScrollRoot to signal when scrolling regions start
and end. It is possible for content from different scrolling regions to
intersect and when they do, the stack of scrolling regions is
duplicated. When these duplicated scrolling regions stacks reach
WebRender, it will scroll them in tandem.
The PushScrollRoot and PopScrollRoot items are currently represented as
StackingContexts in WebRender, but eventually these will be replaced
with special WebRender display items.
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Instead annotate all flows with their owning ScrollRoots. When
processing the display list items into a flattened display list, we add
PushScrollRoot and PopScrollRoot to signal when scrolling regions start
and end. It is possible for content from different scrolling regions to
intersect and when they do, the stack of scrolling regions is
duplicated. When these duplicated scrolling regions stacks reach
WebRender, it will scroll them in tandem.
The PushScrollRoot and PopScrollRoot items are currently represented as
StackingContexts in WebRender, but eventually these will be replaced
with special WebRender display items.
Fixes#13529.
Fixed#13298.
This patch introduces infrastructure for the rule tree, and constructs it.
We don't use it yet, nor have good heuristics for GC'ing it, but this should not
happen anymore once we store the rule node reference in the node.
I haven't messed up with memory orders because I want to do a try run with it,
then mess with them.
Take down the ApplicableDeclarationsCache, use the rule tree for doing the cascade.
Make `FlowRef` a newtype
This creates a sharp distinction between `Arc<Flow>`s, which may be
owned by anyone, and `FlowRef`s, which may only be owned by the
traversal code. By checking the reference count, we ensure that a `Flow`
cannot be pointed to by `Arc`s and `FlowRef`s simultaneously.
This is not a complete fix for #6503, though it is a necessary start
(enforcing the no-aliasing rule of `FlowRef::deref_mut` will require far
more work).
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- [X] These changes fix#14014 (github issue number if applicable).
- [X] These changes do not require tests because the existing tests, plus the added assertions, should be sufficient
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This creates a sharp distinction between `Arc<Flow>`s, which may be
owned by anyone, and `FlowRef`s, which may only be owned by the
traversal code. By checking the reference count, we ensure that a `Flow`
cannot be pointed to by `Arc`s and `FlowRef`s simultaneously.
This is not a complete fix for #6503, though it is a necessary start
(enforcing the no-aliasing rule of `FlowRef::deref_mut` will require far
more work).
Fixes#14014
layout/context: Wrap `image_cache_thread` in a `Mutex<>` as well
`SharedLayoutContext.image_cache_thread` didn't get the `Mutex<>`
treatment along with all the other channels in there, because
`ipc-channel::Sender` is presently inherently `Sync`. I believe this to
be an implementation accident though, that should be rectified in the
future -- not something users should actually rely on...
Note that sharing senders (be it `mpsc` or `ipc-channel`) in is probably
not a good idea anyway: just cloning them -- and letting them handle the
sharing internally -- should be both simpler and cheaper. But right now
that's how things are handled here; so let's go with the flow...
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`SharedLayoutContext.image_cache_thread` didn't get the `Mutex<>`
treatment along with all the other channels in there, because
`ipc-channel::Sender` is presently inherently `Sync`. I believe this to
be an implementation accident though, that should be rectified in the
future -- not something users should actually rely on...
Note that sharing senders (be it `mpsc` or `ipc-channel`) in is probably
not a good idea anyway: just cloning them -- and letting them handle the
sharing internally -- should be both simpler and cheaper. But right now
that's how things are handled here; so let's go with the flow...
Update Rust to 1.14.0-nightly (7c69b0d5a 2016-11-01)
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This makes the API used to build display lists quite a bit simpler and
reduces the amount of auxiliary data structures that need to be passed
around. It is also important preparation work for separating scrolling
areas from stacking contexts.
Track overflow:scroll stacking contexts with ScrollRootId instead of StackingContextId
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This is a step in disassociating scrolling areas from stacking
contexts. Now scroll areas are defined by unique ids, which means that
in the future stacking context will be able to contain more than one.
Remove concept of Layers from Servo
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Layers were a feature of the legacy drawing path. If we re-add them at
some point, it probably makes more sense to make them a product of
display list inspection.
This change also remove a bunch of dead painting code.
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Layers were a feature of the legacy drawing path. If we re-add them at
some point, it probably makes more sense to make them a product of
display list inspection.
This change also remove a bunch of dead painting code.
Simplify TNode a bit, removing has_changed from style
A couple of changes here:
* Remove the option to unset with the dirty bit settes.
* Add an explicit API for setting text node style.
* Hoist has_changed handling into the restyle damage setter and text node style setter.
* Make set_style take a non-Option.
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A couple of changes here:
* Remove the option to unset with the dirty bit setters.
* Add an explicit API for setting text node style.
* Hoist has_changed handling into the restyle damage setter and text node style setter.
* Make set_style take a non-Option.
Add RwLock in more Arc’d things in stylesheets.
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CSSOM needs hold potentially multiple references (through `Arc`) to these objects, and then mutate them.
CC @upsuper
r? @mbrubeck
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With the removal of the legacy rendering path, we don't need to worry
about nested stacking contexts. This change just pushes the
complication to the WebRender conversion step, but a later change will
remove the concept from WebRender as well.
This also helps to prepare for the introduction of ids for particular
scrolling regions, an integral part of multiple ScrollLayers per block.
This removes paint threads, rust-layers dependency, and changes
optional webrender types to be required.
The use_webrender option has been removed, however I've left
the "-w" command line option in place so that wpt
runner can continue to pass that. Once it's removed from there
we can also remove the -w option.
Once this stage is complete, it should be fine to change the
display list building code to generate webrender display
lists directly and avoid the conversion step.
Separating out `REPOSITION` from `REPAINT` allows us to compute
stacking-context-relative positions without rebuilding the display list.
This saves a lot of time when responding to script-to-layout queries.
Create separate layout trace file for each reflow
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Currently only the layout trace from the last reflow is dumped to the file. But the interesting reflow may not be the last one. So we are dumping each of them with filename `layout_trace-{generation}.json`.
This will be used by a GUI viewer to visualize the layout process, which I will check-in later.
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a script query.
This will, rather unfortunately, mean that we might repaint two times if we've
deferred a paint, then get an out-of-band reflow. Still seemed better than not
suppressing paints at all.
Fixes#13131
