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.
We used to get a weird line around the window decoration because the
clamping would hit the outside of the rendered decoration.
To make sure we fall inside take the displayPixelRatio into account.
Also on non-integer scales, make sure we are actually falling inside.
It was needed to work around visual glitches in the wobbly windows
effect. Since the wobbly windows effect renders the animated window into
an offscreen texture, we don't need this workaround anymore.
Furthermore, rather than using half-pixel correction, it is more
desirable to use an offscreen texture as it results in simpler design.
Performance-wise, it's not that bad that we need to start looking for
other ways to get rid of the seams between window contents and deco.
The backend can now optionally wait for the scene to be created before
it updates its outputs, which is necessary for better atomic tests in
the DRM backend.
Currently, the implementation of the DecoratedClient and the decoration
renderer are strongly coupled. This poses a problem with the item based
design as the ultimate goal is to have scene items construct paint nodes
which are then fed to the renderer. The DecorationItem has to have
control over the decoration texture. Another issue is that the scene
cannot smoothly cross-fade between two window states if the decoration
is removed, e.g. from fullscreen mode to normal and vice versa.
This change moves the decoration renderer to the decoration item. With
the introduction of a generic scene texture atlas, we hope to get rid of
the decoration renderer altogether.
attachStreamConsumer and resetOutput are not called as part of the scene
render and as such the context might not be set.
All credit goes to Simon Spinner for his investigation.
BUG: 437573
With high DPI we can't use the image size as a logical size directly.
The other change is use of QPainter::drawImage(QRect target, QImage
image, QRect source)
This slightly confusing method uses logical pixels for the target, but
the source rect is in native pixels of the source.
BUG: 422342
If the egl backend gets deleted this leaves a dangling pointer. In
order to prevent crashes with QPainter or EglStreams also don't try
to create dmabuf textures without a EglGbmBackend.
So far we had a composition setup within kwinrc and kscreen. This
produces flickering sometime and makes the state a bit more flimsy.
This patch changes the kwin's behaviour to use the files produced by
kscreen which are anyways available down the line.
THis simplifies our behaviour down to just one format that we write to
and feed from. This also allows us to leverage it further by using this
format for default setups (which consist in the right file in
~/.local/share/kscreen).
One of the scene redesign goals is to make wayland surface items
re-usable. So we have the same rendering path for drag-and-drop icons,
software cursors, and window surfaces.
The biggest issue at the moment is that window pixmaps are tightly
coupled with scene windows.
This change de-couples window pixmaps from scene windows. In order to
achieve that, some architecture changes were made.
The WindowPixmap class was replaced with the SurfacePixmap class. A
surface pixmap is created by a surface item.
Under the hood, a SurfacePixmap will create a PlatformSurfaceTexture
object, which contains all the information necessary for the renderer.
The SceneOpenGLTexture class was removed. However, the GLX and the EGL
on X11 backends still mess with GLTexture's internals.
As is, kwin with the drm backend results in the most pleasant user
experience on Wayland. Given that and the fbdev being about to be
dropped, making libdrm a required dependency seems a reasonable decision.
This feature was implemented in commit a66eb1a5b9 earlier
Double tap wake up is not a feature to be implemented at compositor
level but rather at the hardware/kernel level. Double tap timer here
means when screen is turned off, libinput will continue to poll the
touchscreen for new events.
double-tap-to-wakeup is generally interrupt at driver/hardware level
which have ability to wake system up even from the sleep.
Provide a option to disable the double tap timer on kwin side for
devices which makes use of suspend since when in suspend kwin can not
wake device up, and that provides confusing user experience.
