Add support to share the WGL context in GDK with the WGL context in GStreamer,
so that we can also use OpenGL in the gstreamer media backend to playback
videos. For now OpenGL/ES is not supported for this under Windows.
The process of setting this up in Windows is a little bit more involved, as:
* The OpenGL support in GstGL requires a GL 4.1 Core context, but we may just
get the GL version from wglCreateContextAttribsARB() that we pass into the
attributes, which is 3.2 by default. So, try to ask for a 4.1 Core context
first if we are asking for anything less.
* There is only one GstDisplay available for Windows, so we just use
gst_gl_display_new().
* We must explicitly tell libepoxy that we are using wglMakeCurrent() outside
of libepoxy that is being used in GdkGL, otherwise we would end up crashing
as the GL/WGL function pointers would become invalid.
* We must also deactivate temporarily the underlying WGL context that was made
current by gdk_gl_context_make_current() so that when
gst_gl_display_create_context() calls wglShareLists(), we won't get bitten
by error 0xaa (resource busy), as some drivers don't handle this well when
the GL context is current in another thread.
For the last two points we make use of macros defined by the platforms that the
build is done for to help us carry out the necessary tasks as needed.
Thanks to Matthew Waters for the info on integrating GstGL and windowing
toolkits on Windows.
Remove a boatload of "or %NULL" from nullable parameters
and return values. gi-docgen generates suitable text from
the annotation that we don't need to duplicate.
This adds a few missing nullable annotations too.
If we want to add an EGL implementation for the X11 backend, we are
going to need to move the GLX bits into their own class. The first step
is to declare GdkX11GLContext as an abstract type, and then subclass it
into a GdkX11GLContextGLX type, which includes the whole GLX
implementation.
Width and height of a GdkMonitor are derived via wl_output which
talks about physical dimensions of a device and compositors usually
implement this as the untransformed values (e.g. weston, wlroots).
Since the GTK client has no way to figure out if a monitor was rotated,
transform the physical dimensions according to the applied wayland
transform to have the physical dimensions match the logical ones.
Mutter flips the physical dimensions itself but doesn't announce the
transform so this shouldn't break anything there.
Rewrite this in a way that doesn't depend on kernel
header defines at the time the wayland scanner was run.
This was causing the build to break on Centos 8, where
a bunch of fourcc formats are missing.
Some GL drivers such as Mesa-D3D12 do not allow one to call SetPixelFormat() on
a given HDC if one pixel format has been already set for it, so first check the
HDC with GetPixelFormat() to see whether a pixel format has already been set
with the HDC, and only attempt to acquire the pixel format if one has not been
set.
This will fix running with GL/NGL on Windows using the Mesa drivers.
When building for homebrew/linuxbrew on Ubuntu 16.04, memfd_create() is
not available and causes the build to fail.
This adds a proper check for the function.
When reading text, we need to check we terminate the G_TYPE_STRING
string with a null byte, because the clipboard does not guarantee one.
So just append a \0 to the stream.
Fixes#3899
