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.
WebRender is an experimental GPU accelerated rendering backend for Servo.
The WebRender backend can be specified by running Servo with the -w option (otherwise the default rendering backend will be used).
WebRender has many bugs, and missing features - but it is usable to browse most websites - please report any WebRender specific rendering bugs you encounter!
