We initially assumed that copy_sub_buffer is synchronized on
which is only the case for a subset of GPUs for example it is not
synchronized on INTEL gen6 and gen7, so we remove this assumption
for now.
We should have a specific driver / GPU whitelist if we want to enable
this.
https://bugzilla.gnome.org/show_bug.cgi?id=669122
Reviewed-by: Robert Bragg <robert@linux.intel.com>
Reviewed-by: Neil Roberts <neil@linux.intel.com>
This patch basically restores the logic from 1.6. There we assumed that
glXCopySubBuffer won't tear and thus only needs to be throttled to the
framerate, while glBlitFramebuffer needs to always wait to avoid
tearing.
With Nvidia drivers specifically we have seen that glBlitFramebuffer is
not synchronized. Eventually the plan is that Cogl will actually take
into consideration the underlying driver/hw vendor and driver version
and we may want to only mark glBlitFramebuffer un-synchronized on
Nvidia.
https://bugzilla.gnome.org/show_bug.cgi?id=659360
Reviewed-by: Robert Bragg <robert@linux.intel.com>
This migrates all the GLX window system code down from the Clutter
backend code into a Cogl winsys. Moving OpenGL window system binding
code down from Clutter into Cogl is the biggest blocker to having Cogl
become a standalone 3D graphics library, so this is an important step in
that direction.