[qpa] Drop PlatformContextWayland which uses wayland egl for OpenGL
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Authored by graesslin on Feb 14 2019, 4:48 PM.

Details

Summary

Using the Wayland protocol for OpenGL is no longer used or useful. KWin
internal windows only use OpenGL through QtQuick. We either have the
sharing context (KWin uses OpenGL for compositing) or we have the
QPainter compositor which also turns QtQuick to use software renderer.

Thus a situation where the Wayland platform context is useful doesn't
exist any more. Removing it helps getting the QPA plugin Wayland free.

Test Plan

Run nested KWin triggering Outline once with OpenGL and once
with QPainter compositor.

Diff Detail

Repository
R108 KWin
Branch
drop-platform-context
Lint
Lint OK
Unit
No Unit Test Coverage
Build Status
Buildable 8301
Build 8319: arc lint + arc unit
graesslin created this revision.Feb 14 2019, 4:48 PM
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graesslin requested review of this revision.Feb 14 2019, 4:48 PM

or we have the QPainter compositor which also turns QtQuick to use software renderer.

Unfortunately that's not true if we still want to switch at runtime.
QQuickWindow::setSceneGraphBackend is only followed if set before the first QQuickWindow is created.

or we have the QPainter compositor which also turns QtQuick to use software renderer.

Unfortunately that's not true if we still want to switch at runtime.
QQuickWindow::setSceneGraphBackend is only followed if set before the first QQuickWindow is created.

We cannot switch at runtime: it's possible that we still allow it, but that's a bug. No OpenGL application would continue to work after switching from OpenGL to QPainter compositor. Basically switching OpenGL/QPainter and vice versa needs to become a requires reboot setting.

I'm fine with delaying this change till it's not possible to switch - on the other hand switching is broken so I don't think it must be a requirement.

We don't seem to be able to switch currently.
I didn't know if it was something you ever wanted to restore. I think it should be possible to blit the GL clients and support it.

If it's not something we'll ever want - ship it!

davidedmundson accepted this revision.Feb 18 2019, 6:01 PM
This revision is now accepted and ready to land.Feb 18 2019, 6:01 PM
This revision was automatically updated to reflect the committed changes.