Put them all into one function, and move the function pointers out of
glx_session_t, making them global variables (because them don't change
after initialized). Remove the function pointer typedefs and replace
them with the ones in glxext.h
We also only lookup the functions once per a lifetime of compton.
Signed-off-by: Yuxuan Shui <yshuiv7@gmail.com>
Background: To bind a Xorg window content to a OpenGL FBConfig, which
has to match the color format the Xorg window is using.
Previously, compton just find a FBConfig that has the same depth. This
led to chjj/compton#477, which has been fixed by a ugly hack.
The commit refactor the lookup mechanism to take as much into
consideration as we reasonably can. Hopefully preventing similar
breakages in the future.
Also, some code sharing between the old and new glx backend.
Signed-off-by: Yuxuan Shui <yshuiv7@gmail.com>
This commit introduced a new, modular backend interface. The interface
is not very good, since I don't think I fully understand all the
requirements writing a backend have. But this is a good first step.
This commit also includes an initial xrender backend written using the
new interface, and some opengl backend related helper functions, which
are taken from the old opengl backend.
However, there is not integration with the core compton yet. compton
will still use the old backend code. This commit is here so we can get
the automated build test.
What is implemented in the new xrender backend:
* Windows with transparency
* Shadow
* Opacity
* Wallpaper (getting the root pixmap)
* Blur
Known problem with the xrender backend:
* It is slower
Things that still need to be figured out:
* What is the better way to add vsync to the new backends
Signed-off-by: Yuxuan Shui <yshuiv7@gmail.com>