portal 2 pc slitscreen made easy

You can play coop without the need of any of the annoying .cfg files if you just assign the controller to player 1 and let player 2 use the keyboard.
its pretty simple : connect your X360 controller and start the game. Make sure that controller is enabled from the options. Load a map (ss_map mp_coop_start), then, in console type:
sv_cheats 1
in_forceuser 1
what this does is force the keyboard input to player 2, but the controller input remains mapped to player 1 by default, and VOILA! u have a working multiplayer game!

Read more: http://segmentnext.com/2011/04/20/how-to-play-portal-2-split-screen-coop-on-pc/#ixzz1MtwHtQru

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