[engine] Not specifying populate_existing_damage should result in full repaint #119601
Description
I'm using my own custom embedder (which is based on the engine's Embedder API) and I have a rendering issue after upgrading the engine from 3.3 to 3.7 (stable). According to my experiment, it seems the newly added API populate_existing_damage is not functioning as it is described in the documentation. It says not specifying the callback will result in full repaint but in reality, the repaint does not occur.
/// ...
/// ID. Not specifying populate_existing_damage will result in full
/// repaint (i.e. rendering all the pixels on the screen at every frame).
FlutterFrameBufferWithDamageCallback populate_existing_damage;I think the problem is with either the return value of gl_populate_existing_damage in embedder.cc or the supports_partial_repaint flag in embedder_surface_gl.cc:
- Shouldn't
existing_damagebe set tostd::nulloptinstead ofSkIRect::MakeEmpty()? - The
partial_repaint_enabledvalue is not used anywhere. - Isn't
supports_partial_repaintalways true?
One way to work around the issue is to implement the populate_existing_damage callback in my embedder, but I think that's not a real solution. Could anybody confirm that this is a regression in the engine?
Logs
$ flutter doctor -v
[!] Flutter (Channel unknown, 3.7.0, on Ubuntu 20.04.5 LTS 5.15.0-56-generic, locale en_US.UTF-8)
! Flutter version 3.7.0 on channel unknown at /home/swift/Git/flutter-tizen/flutter
Currently on an unknown channel. Run `flutter channel` to switch to an official channel.
If that doesn't fix the issue, reinstall Flutter by following instructions at https://flutter.dev/docs/get-started/install.
! Unknown upstream repository.
Reinstall Flutter by following instructions at https://flutter.dev/docs/get-started/install.
• Framework revision b06b8b2710 (7 days ago), 2023-01-23 16:55:55 -0800
• Engine revision b24591ed32
• Dart version 2.19.0
• DevTools version 2.20.1
• If those were intentional, you can disregard the above warnings; however it is recommended to use "git" directly to perform update checks and upgrades.