The main motivation behind the split is to simplify client buffer code
and allow adding new features easier, for example referencing the shm
pool when a shm buffer is destroyed, or monitoring for readable linux
dmabuf file descriptors, etc.
Also, a referenced ClientBuffer cannot be destroyed, unlike the old
BufferInterface.
DrmPipeline is now what contains all the thing related to drm calls,
instead of DrmOutput. This allows for some more flexibility and tidies
the code up a bit. Additionally instead of rolling back changes if
presentation fails, changes are directly tested with atomic test only
commits.
While always calling showCursor isn't a problem for when there's no
pointing device as the cursor image is empty in that case, it can
cause a temporarily stuck cursor image when it's supposed to be
hidden because of touch input
If a wl_eglstream buffer is attached to a surface, but then later a different
type of buffer, such as a dmabuf, is attached to the same surface, kwin will
mistakenly keep trying to acquire frames from the EGLStream associated with the
previous buffer. This can happen if an Xwayland window is made full-screen
causing it to switch to the flipping presentation path, for instance. The
result is that the window contents will no longer be updated.
Instead, the eglstream backend's loadTexture and updateTexture functions should
first pass the buffer to eglCreateStreamAttribNV. If it fails with
EGL_BAD_STREAM_KHR, that indicates it is indeed a wl_eglstream, and that we've
already associated a server-side EGLStream with it in attachStreamConsumer, so
we can proceed as usual. If it fails with EGL_BAD_ACCESS, though, that
indicates it is not a wl_eglstream and we should fall back to the parent class
which handles attaching other buffer types. If it doesn't fail at all, that
means the client tried to attach a new wl_eglstream to a surface without first
attaching the stream consumer. There's not really a great way to handle this,
so just re-use the previous EGLStream.
This is to ensure that both kwin and Qt use the same EGLDisplay. Note
that the native context handle can have no display, however it's very
unlikely to happen.
There are EGL implementations that will refuse to create a context if
the share context belongs to other EGLDisplay. Currently, that's the
case on some platforms.
If eglGetPlatformDisplayEXT() is called with the same parameters, it'll
return the same EGLDisplay. The main motivation behind this change is to
ensure that both kwin and Qt share the same EGLDisplay, QtXCB calls
eglGetPlatformDisplayEXT() without any additional args.
If EGL_PLATFORM_X11_SCREEN_EXT is not specified via attrs, the EGL
implementation will use the default screen, which is the same as
m_x11ScreenNumber.
Putting the OpenGL post processing rotation into its own class cleans
the EglGbmBackend code up a bit and adds post processing rotation for
the EglStreamBackend
Currently, if discard() is called, kwin will crash because
EglPixmapTexture does not override the discard method.
In principle, neither GlxPixmapTexture nor EglPixmapTexture should mess
around with internals of the GLTexture class. It is better to have a
wrapper texture with a bind method, which will re-bind the pixmap to the
opengl texture if necessary.
It seems like without a surface creation of the scene fails somehow. At
least until the exact problem is solved, update outputs for EglStream
gpus before creating the EglStreamBackend.
BUG: 438363
So far, we were creating a model view with the complete scene rendered
(even if we didn't render the windows themselves). This required us to
have a big glPerspective spanning the entire scene and we were just
cropping it as we rendered it into a smaller texture.
This changes our scenes so we have the correct matrix set up at all
times.
Specifically in the case of the Pinephone, this solves the following
issue where we were unable to connect external displays because it
exceeded GL_MAX_VIEWPORT_DIMS:
https://invent.kde.org/teams/plasma-mobile/issues/-/issues/11
The Xrender backend was added at the time when OpenGL drivers were not
particularly stable. Nowadays though, it's a totally different situation.
The OpenGL render backend has been the default one for many years. It's
quite stable, and it allows implementing many advanced features that
other render backends don't.
Many features are not tested with it during the development cycle; the
only time when it is noticed is when changes in other parts of kwin break
the build in the xrender backend. Effectively, the xrender backend is
unmaintained nowadays.
Given that the xrender backend is effectively unmaintained and our focus
being shifted towards wayland, this change drops the xrender backend in
favor of the opengl backend.
Besides being de-facto unmaintained, another issue is that QtQuick does
not support and most likely will never support the Xrender API. This
poses a problem as we want thumbnail items to be natively integrated in
the qtquick scene graph.
