Enhanced, OpenGL-only Quake II engine.  It brings plethora of improvements
over the original, including, but not limited to:

  - Optimized rendering backend, support for new textures and shaders
  - Framerate decoupling: your video framerate can be infinite while your
    network framerate is 30
  - R1Q2 protocol version 35 supported on the client-side
  - Improved console (highly customizable, better tab autocompletion)
  - Various improvements in crosshairs, HUD, particles and decals
  - Optimized virtual file system, new supported file formats, etc.

WWW: http://bfeared.com/library/quake/archive/quakedev/egl/