Although this has been documented elsewhere (see here and here), the instructions are mostly geared towards people who want to use a gamepad for one player and a keyboard/mouse for another player. If you are fortunate enough to have two gamepads for your PC, then playing Left 4 Dead in split screen mode is surprisingly easy to set up.
Step 1: Download this Xbox 360 controller emulator by Evaldas Jocys. The file you want is named something like x360ce.App-18.104.22.168.zip, give or take the version number. (Sound familiar? This is the same thing we did for Dead Rising 2.)
Step 2: Extract the zip archive to your Left 4 Dead executable directory, which will be something like C:\Program Files (x86)\Steam\steamapps\common\left 4 dead.
Step 3: Run the x360ce executable file. When the program launches, it will prompt you to create the x360ce.ini file. This is the file that holds the configuration settings for the program. It will also prompt you to create the xinput1_3.dll file. This is the library file that gets compiled along with the configuration settings and will enable your gamepad to work with the game. Click Yes on both of these prompts to create the files.
Step 4: At this point, you should be looking at a new window that says “New Device Detected.” Leave the first radio button checked – the one that says “Search automatically for settings” – along with the checkbox that says “Search the Internet” and click “Next” at the bottom of the window. Finally, click Finish at the bottom of the next window to import the settings. If the program displays a green box on the tab for the controller you have selected, then you can continue to step 5. If it displays a red box on the tab, then see the troubleshooting section below.
If you’re using two gamepads, repeat this step for the second one.
Step 5: Click Save at the bottom-right corner of the window and close the program.
Step 6: Go to your Left 4 Dead bin directory, which will be something like C:\Program Files (x86)\Steam\steamapps\common\left 4 dead\bin. Rename the xinput1_3.dll file to xinput1_3.dll.old.
Step 7: Launch the game. Click on Options, then on Keyboard/Mouse. Make sure “Allow Developer Console” and “Gamepad” are both enabled. Then click Done.
Step 8: Hit the tilde key (~) on your keyboard to open the console and type:
Replace mapname with the actual name of a map. Auto-completion in the console should help you out here.
That’s it! You’re done. Unless you are playing Left 4 Dead 2. In that case, enter this command in the console once the map has finished loading:
connect_splitscreen localhost 2
When you’re done using a controller and want to use your keyboard/mouse again, go back into Options, Keyboard/Mouse, and disable the gamepad.
What if x360ce doesn’t recognize my gamepad?
Since I normally use a fairly ubiquitous gamepad (Logitech Wireless Gamepad F710), I had never encountered this problem until I tried my other one (PS3 Afterglow Controller by PDP). If x360ce doesn’t recognize your gamepad, it will display a red box on the tab for that controller and the controller diagram will be all grayed out:
Go to the Settings Database tab on the top row of tabs. Under Controller/Device, select the gamepad that’s having problems. Then click on the Global Settings tab to get a list of available configurations from the internet:
I have my list sorted by the Users column. I think that, by default, x360ce will use the highest ranked configuration for your gamepad settings. In my case, it was using the top one in the list, with 5C1EA9F1 under SID and 11 Users. To use a different configuration, double click on another entry in the list. Then click Yes to import the settings. A couple of seconds after that, if you picked the right one, the red box on the controller tab should change to a green box:
At this point, you should be able to push the buttons on your controller and see the corresponding buttons light up in the diagram on the controller tab. This will tell you for sure if your gamepad settings are working. Do the same for the joysticks to make sure those are working too.
If everything checks out, then you can resume from step 5 above.