gecko-dev/gfx/webrender_bindings
Brad Werth 6af8eda593 Bug 1731136 Part 5: Make macOS native compositor and NativeLayerCA handle backdrop r=mstange
layers.


This makes the macOS native compositor claim the ability to handle color
layers and makes NativeLayerCA actually do it. Color layers have a different
structure than other layers. Color layers apply the color to the
wrappingCALayer, and have no contentCALayer at all. That means that the
color layers are always sized to the layer's clip rect.

This also contains a drive-by fix to handle the case where an mOpaquenessTintLayer
exists when mMutatedSpecializeVideo is set to true. Before this change, in such a
case, the opaqueness layer will not be associated with the recreated wrapping layer.

Depends on D128131

Differential Revision: https://phabricator.services.mozilla.com/D128545
2022-06-01 19:40:04 +00:00
..

To build and run WebRender in Gecko:
1. Install Rust if you don't have it already
   If you are doing gecko builds already, you should already have Rust as it is a build requirement.
   If not, you can install it using |mach bootstrap| (recommended) or from https://www.rust-lang.org/
       Note: If installing manually, use the stable 64-bit release - on Windows make sure to use the MSVC ABI installer.
   Ensure that rustc and cargo are in your $PATH (adding $HOME/.cargo/bin/ should be sufficient)
2. Build using |mach build|.
   You don't need anything special in your mozconfig for local builds; webrender will be built by default.
3. Run with |MOZ_WEBRENDER=1| in your environment. e.g. |MOZ_WEBRENDER=1 ./mach run|.
   Alternatively, you can set the gfx.webrender.enabled pref to true (browser restart required).
   Note that on Linux, acceleration is disabled by default and it needs to be enabled for WebRender to work.
   On Linux you can enable acceleration by putting |MOZ_ACCELERATED=1| in your environment, or setting layers.acceleration.force-enabled to true in about:config.
4. Verify WebRender is enabled. You can do this by going to about:support and checking the "Compositing" line in the Graphics section. It should say "WebRender".
   There should also be a WebRender section under "Decision Log" in about:support, which will provide some more detail on what caused it to be enabled/disabled.

When making changes:
    - Make the changes you want.
    - Run |mach build| or |mach build binaries| as desired.

For a debug webrender build:
    Use a debug mozconfig (ac_add_options --enable-debug)
    You can also use an opt build but make webrender less optimized by putting opt-level=0 in the [profile.release] section of your toolkit/library/rust/Cargo.toml file
    See also https://groups.google.com/forum/#!topic/mozilla.dev.servo/MbeMcqqO1fs