Gtest options are keys that you can use while playing the demo.
 ~       = Show/Hide the Console
 F12     = Take screenshot and create BMP file (Glide driver only)
 Ctrl+F8 = Switch between wireframe and textured modes (Glide only)
 I       = Switch to God Mode
 O       = Switch the view between Player and Bots
 P       = Activate/deactivate Path Light
 D       = Debug Print
 L       = Reload the current level
 N       = Activate/deactivate Multi-Path Light


When you run Gtest, you can pass some parameters using the DOS prompt or a PIF file with the following format:
    GTEST.EXE -switch [option]
where "switch" is one of the following switch and must have the character "-" in the front and "option" is the optional parameter for the switch, described below:

 -Server                GTest will start as a server.
 -Dedicated             Configure that server to be a dedicated server.
 -Client                Start GTest as a Client (default).
 -BotPathDebug          Mode debug for PathPoints.
 -Record [.dem file]    Record a demo file .DEM (see the file DEMO.INI).
 -Play [.dem file]      Play a demo file .DEM (see the file DEMO.INI).
 -IP []  Try to connect to that IP address.
 -Map [.bsp file]       Open GTest with a specific BSP level.
 -Gamma [value]         Set the Gamma value for GTest.
 -ShowStats             Start GTest with the statistics turned on.
 -Mute                  No sound.
 -VidMode [videomode]   Start GTest in a specific video mode.
 -PickMode              Displays the Pick Mode dialog box before starting GTest.
 -Fog                   Turn on the Fog.
 -FarClip [value]       Set the FarClipping.