Allow to use the opengl context sharing feature if the original
context has been used already.
This is only possible on win32 with wglShareLists because on other
backends, the sharing is made when a context is created.
This new feature is only usefull when using external context
because gst-gl internally makes sure that the orginal context is not
already used when sharing it.
Fix bug #611067
glmixer can be seen as a glfilter except it handles N requested
sink pads.
Each sink pad and the src pad are video/x-raw-gl.
glmixer is responsible for managing different framerates from inputs.
It uses OpenGL context sharing. It means that each input is in its
own OpenGL context shared together and shared with the OpenGL context
of the ouput gl chain.
Also add a glmosaic which is an example of implementation of glmixer.
For now glmosaic is a cube but it will be fixed in the next commits.
For now the glmixer has some weird behaviours in some configurations
but it will be improved in the next commits.
The autotools builds is temporarly broken since those changes
have been made on win32.
Fixes bug #584877
Before this commit calling "gst_x_overlay_set_xwindow_id" more
than one time, had no effect.
It mainly affects the glimagesink implementation.
But on win32 (and CE), some stuff has to be done to
release the old parent.
And add a switchxoverlay example where the user
can click on left/right part of the main window to
switch the xoverlay.
The external opengl context must be specify when creating
our OpenGL context (glx) or just after (wgl).
When calling glXCreateContext or wglShareLists, the
external opengl context must not be current.
Then our gl context can be current in the gl thread while
the external gl context is current in an other thread.
See tests/examples/clutter/cluttershare.c
This reverts commit 96e4ab18c2cf9876f6c031b9aba6282d0bd45a93.
You should have asked first. And you would have been told "no",
because it causes people on development branches to do a huge
amount of extra work.
