quake3-ioquake3

Quake III Arena and it's demo don't offer current wide screen resolutions in the menu.

To switch to such a resolution, you will have to enter something like this in the quake console (invoke with ~ by default)

r_mode -1; r_customwidth 2560; r_customheight 1440; r_fullscreen 1; vid_restart

Or call the quake commandline with these parameters

$ quake3 +set r_mode -1 +set r_customwidth 2560 +set r_customheight 1440 +set r_fullscreen 1