glStringMarker is usually only available when running under some
kind of GL debugger, and can be used to insert strings into the
GL command string. Writing logs using it can be useful, since it
lets us correspond GL calls with what happens in compton.
More info about the extension can be found here:
https://www.khronos.org/registry/OpenGL/extensions/GREMEDY/GREMEDY_string_marker.txt
Signed-off-by: Yuxuan Shui <yshuiv7@gmail.com>
So that the format arguments will only be evaluated if the log is
enabled by the log level. Allow us to add more expensive logs without
impact performance when they are not enabled.
Signed-off-by: Yuxuan Shui <yshuiv7@gmail.com>