Summary:
To use eglCreateImageKhr for an X11 pixmap we need an EGLDisplay created
for the same XDisplay as the X11 pixmap. This means if we created an
EGLDisplay for a GBM device, we are not allowed to load a texture from
the X11 pixmap and can result in a crash in the driver.
Similar in the nested X11 setup the EGLDisplay is created for the
rendering window, but the X11 pixmaps are from the Xwayland server KWin
started. They don't belong to the same windowing system.
This change addresses this problem by moving the loading of X11 pixmaps
from AbstractEglTexture to EglTexture of the EglOnX11Backend. Thus for
any usage on a non X11 platform we cannot hit the code path any more.
In addition the nested X11 platform can indicate that it doesn't support
it and thus also doesn't go through the code path.
Test Plan: Tested standalone and nested X11 platform
Reviewers: #kwin, #plasma_on_wayland
Subscribers: plasma-devel, kwin
Tags: #plasma_on_wayland, #kwin
Differential Revision: https://phabricator.kde.org/D1857
As we don't have GLPLatform before the backend is fully created
the AbstractEglBackend has a new method isOpenGLES() -> bool
which determines based on QOpenGLContext::openGLModuleType().
This change introduces a mechanism for internal windows to be rendered
to a QOpenGLFramebufferObject to be composited using the texture bound
to the FBO. This is useful for in-process rendering (e.g. QtQuick) and
at the same time bypassing the windowing system.
The OpenGL context of the QOpenGLFramebufferObject needs to be sharing
with the compositing OpenGL context.
Each of the backends becomes a plugin. This allows kwin_wayland to load
the requested plugin and kwin itself doesn't need to link all the
libraries needed. E.g. libdrm is no longer linked if running kwin_x11.
Also this allows to create backends for the non-standard EGL platforms
(examples could be raspberrypi or Android devices).
For each DrmOutput a gbm_surface and EglSurface is created. When
rendering per screen the context is made current on each of the
surfaces.
Note: viewport handling needs to be improved by e.g. passing through
the scene to restore to correct viewport after dropping an FBO.
Furthermore it seems like buffer age is not working correctly in this
setup (not overly surprising).
Dynamic changes are not yet supported.
There's quite some overlap and duplicated code. This AbstractEglBackend
tries to merge the two backends a little bit again.
This also introduces an AbstractEglTexture which supports both X11 and
Wayland "pixmaps" so that EglOnXBackend can support Wayland buffers.
