The UI is Qt4. See the dependencies here: https://aur.archlinux.org/packages/vogl-git/?setlang=en
Phoronix: A Look At Valve's VOGL UI
Rich Geldreich has shared some screenshots of their VOGL OpenGL debugger in action when debugging an OpenGL problem with Xonotic...
Where are the screenshots?
## VGA ##
AMD: X1950XTX, HD3870, HD5870
Intel: GMA45, HD3000 (Core i5 2500K)