I have a follow up PR for Servo that uses the new border-image
APIs, but I'll land that separately, so that we don't delay
landing the WR update itself.
This includes a WR update that improves pixel snapping. Specifically,
the non-transform shader now snaps to device pixels in world space,
rather than local space.
This makes 31 new tests pass, and adds 4 new failures.
Of the new failures:
- The three background size tests appear to be an OSMesa accuracy
issue. Near the bottom of the image, a small number of pixels
are different from the reference by a value of 1.0 / 255.0. I've
confirmed on 3 real GPUs and also on llvmpipe that the tests
match on those devices. This would be a good case for fuzzy test
support in WPT.
- The other failing test appears to have unreasonable accuracy
requirements as it also fails on Gecko and Chromium in the same
way that the test now fails on WR.
switch to using webrender_traits::ImageData
update use of webrender_traits::StackingContext in layout
use webrender_traits::channel::msg_channel in webgl ipc
fix use of resource_override_path in components/servo/lib
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 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.
Prefer auto-generation for some keyword props
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r? @Manishearth or @emilio
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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.
Remove the concept of nested stacking contexts from display list builder
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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.
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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.
Integrate stacking contexts into the display list by adding two new
entry types, PushStackingContext and PopStackingContext. This allows us
to eliminate the ugly offsets map that DisplayList used to contain
and seems to speed up display list construction. With this approach
we are able to also completely prune pseudo-stacking contexts from the
final display list and remove their (minimal) overhead from display
list traversal Traversing the display list is also a bit simpler now.
Additionally, this will allow easier editing of the DisplayList to
properly support scrolling roots. The push/pop entries can be
duplicated to clone complex StackingContext trees between layers.
This updates webrender to include the webgl related changes
needed for this patch. There was an additional commit in
webrender before these landed, so also copy the shaders
for that change across. There is an interface change to
webrender push_image. For now, just pass zero, which is a
no-op to this function. A follow up commit will introduce
the servo specific changes to use this new interface.
WebRender.
This happens asynchronously, just as it does in non-WebRender mode.
This functionality is a prerequisite for doing proper display-list-based
hit testing in WebRender, since it moves the scroll offsets into Servo
(and, specifically, into the script thread, enabling iframe event
forwarding) instead of keeping them private to WebRender.
Requires servo/webrender_traits#55 and servo/webrender#277.
Partially addresses #11108.
Replace character indices with UTF-8 byte offsets throughout the code dealing
with text shaping and breaking. This eliminates a lot of complexity when
converting from one to the other, and interoperates better with the rest of
the Rust ecosystem.
Merge DisplayListEntry into DisplayItem
We don't really need two levels of abstraction for every element in the
DisplayList. This simplifies the complexity of the data structure in
preparation for providing documentation and properly handling scrolling
roots.
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We don't really need two levels of abstraction for every element in the
DisplayList. This simplifies the complexity of the data structure in
preparation for providing documentation and properly handling scrolling
roots.
Since the display list is already sorted before it is passed to
WebRender, we don't need to pass the stacking level information any
longer. Update webrender, webrender_traits, and gleam.
over the data as well.
WebRender doesn't need the data, as it acquires it separately.
About a 50%-100% improvement in display list building time on
browser.html.
array, and consolidate the multitude of display list messages into one.
Improves display list building performance by 50%-100% for small display
lists.
Now that WebRender uses an Iframe display item, we do not need the Noop
item for the non-WebRender path. We can simply reuse the Iframe display
item. Also remove the layer_id member from the LayeredItem struct, as
it is unused.
Instead of producing a tree of stacking contexts, display list
generation now produces a flat list of display items and a tree of
stacking contexts. This will eventually allow display list construction
to produce and modify WebRender vertex buffers directly, removing the
overhead of display list conversion. This change also moves
layerization of the display list to the paint thread, since it isn't
currently useful for WebRender.
To accomplish this, display list generation now takes three passes of
the flow tree:
1. Calculation of absolute positions.
2. Collection of a tree of stacking contexts.
3. Creation of a list of display items.
After collection of display items, they are sorted based upon the index
of their parent stacking contexts and their position in CSS 2.1
Appendeix E stacking order.
This is a big change, but it actually simplifies display list generation.
