I usually have relatives over, and my relatives usually have kids, and instead of watching me play Garry’s Mod the kids want to play too. I made this for the kids, so that they’d be able to play Garry’s Mod with me or if two of them wanted to play Garry’s Mod.
Currently works for both Garry’s Mod beta, and regular Garry’s Mod. Though beware, the beta version squishes the screen for some odd reason, and the regular version has some artifact errors due to, I guess, the FOV.
Other problems for the splitscreen person:
Major glitch out when you enter a vehicle.
Cannot rotate and object with the physgun.
Concommands to bind:
gm_splitscreen.dll is a rename of gm_botcontroller.dll from: http://www.facepunch.com/threads/736452
All I did was recompile it for the orangebox engine.