IN_FORMATS contains information about which buffer formats can be
scanned out with a given drm plane. Using these plane-specific
format+modifier combinations as well as explicit modifiers in
general can yield bandwidth and performance improvements,
especially in multi-gpu systems.
We use surfaceless contexts with internal windows. We also require
the EGL_KHR_surfaceless_context extension for making context current
without outputs.
Arguably, we could use pbuffers, but since mainstream drivers (Mesa and
NVIDIA) support surfaceless contexts, the extra complexity doesn't buy
us anything.
When the last output gets disconnected, create a virtual output as a
placeholder until we have access to a physical output again. While
this placecholder never gets rendered to, with virtual outputs in
general that is possible (with gbm and qpainter atm) and can be done
for future use cases like wireless displays.
CCBUG: 420160
CCBUG: 438839
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.
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
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 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.
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.
When we release the buffers that also removes the drm fbs.
This causes failing atomic commits that the atomic code
doesn't (yet) handle correctly, the result is a black
screen when compositing is restarted.
Most wayland-native apps provide buffers that aren't suitable
for direct scanout; the message usually only spams the log full
without proper reason or useful information
We'd be relying on AbstractEglDrmBackend on calling cleanup but we'd be
doing it when cleanupSurfaces cannot be reached out anymore, turning it
into a half-baked cleanup.
Instead call cleanup from the leaf class destructors.
Otherwise drmModeAtomicCommit() in DrmOutput::doAtomicCommit() fails due
to unmatched buffer sizes.
While rendering continues working properly, this makes drm freak out and
try to go back to a previous state (see the test commit in
presentAtomically()) that in turn starts issuing screen events to every
process even though it's just to say the same thing. The fact that this
happens per frame makes the system unusable as soon as fullscreen starts
happening on a scaled display.
Another thing we could do is get EglGbmBackend::scanout() to take care
of the resizing.
Once in a while, we receive complaints from other fellow KDE developers
about the file organization of kwin. This change addresses some of those
complaints by moving all of source code in a separate directory, src/,
thus making the project structure more traditional. Things such as tests
are kept in their own toplevel directories.
This change may wreak havoc on merge requests that add new files to kwin,
but if a patch modifies an already existing file, git should be smart
enough to figure out that the file has been relocated.
We may potentially split the src/ directory further to make navigating
the source code easier, but hopefully this is good enough already.
2021-02-10 15:31:43 +00:00
Renamed from plugins/platforms/drm/egl_gbm_backend.cpp (Browse further)
