All backends already have an init method so far called from the ctor.
This change moves the call to init out of the OpenGL backends and makes
it the responsibility of the creating code to also call init on the
backend.
This change makes it easier to have virtual methods being called during
the initialization.
For the functions from GL_FOO_robustness we want to resolve it by
ourselves in order to add a custom implementation if it's not available.
Unfortunately once epoxy.h is included this breaks as epoxy defines the
names and so through the preprocessor epoxy always wins.
So we need different names: all functions from robustness get a "kwin"
prefix and the usage is changed everywhere in kwin source code.
REVIEW: 125883
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().
Very basic: all screens have same size and are ordered from left to
right. It's mostly meant to allow easy test cases with multi-screen.
The quick tiling test demonstrates how it's used.
The backend is based on drm's gbm backend and also uses the GBM
platform, but with the default display allowing the driver to pick
a device. In addition it doesn't use a surface, but a surfaceless
context with a framebuffer object to render to. Given that it diverged
too much from drm's backend to allow more code sharing.
If KWin is started from a tty it gets a proper driver, if KWin is started
in a X11 session it only gets llvmpipe. Given that there is a chance that
the autotests using the virtual backend will fail. In that case a follow
up patch will enforce either O2 or Q.
A new backend which doesn't present the rendered output. It uses a
QPainter scene, renders to a QImage but doesn't present it anywhere.
Thus a real virtual backend.
By exporting the environment variable KWIN_WAYLAND_VIRTUAL_SCREENSHOTS
the backend creates a temporary dir, prints the path to std-out and
saves each rendered frame into that directory. Of course with exit it
will be deleted again.
