GLXOSD is an extensible on-screen display (OSD)/overlay for OpenGL applications running on Linux with X11 which aims to provide similar functionality to MSI Afterburner/RivaTuner OSD. It can show FPS, frame timings, temperatures and more in OpenGL games and applications. It can also be used to benchmark games, much like voglperf.
Hi, it looks like the black boxes issues as seen in #18 is back for some reason.
Running on Ubuntu 15.10 64bit with a GTX 680 on Nvidia 355.11 drivers, this is what I see in Alien Isolation with GLXOSD: