Bizhawk Co-op Netplay

bizhawk-co-op is a Lua script for BizHawk that allows two or more people to play a co-op experience by sharing inventory/ammo/hp over the network. This will work with vanilla versions of the games and also randomizers.

Mega Man Battle Network 3

Enable two instances of BizHawk running MMBN 3 to communicate with each other to syncronize various in game items and statuses (library, zenny, etc.) to allow for 100% completion in each game (which normally requires trading version exclusive battlechips).

API Specification (WIP)

sync library (could use ramsync, no side effects) sync zenny (abusable with saving/reseting) sync bugfrags (abusable with saving/reseting)

sync packs (complicated) sync folder (complicated) sync navicust parts (complicated)

sync regups (questionable) sync key items (questionable)

sync jobs (technically possible) sync virus lab (technically possible)

disable cheats (may or may not need, for 3)

Notes

Might need to maintain external state to prevent save abuse

If the powershell script doesn't run, try running: Set-ExecutionPolicy -ExecutionPolicy RemoteSigned -Scope CurrentUser

References

Our fork of TestRunner's bizhawk-co-op https://github.com/TeamBattleNet/CooPatch

Our Project Page https://github.com/TeamBattleNet/CooPatch/projects/1

Markro's BN3 function hooks https://github.com/TeamBattleNet/CooPatchTest/blob/master/CooPatch.lua

VBA/Bizhawk shim, to allow lua scripts written for VBA-rr to run in BizHawk. (more relevant for our other projects) https://gist.github.com/adituv/265be838fa183d93634b3fd9833c0479

Check comm tab for built in bizhawk networking (probably won't use) http://tasvideos.org/Bizhawk/LuaFunctions.html

bizhawk-co-op is a Lua script for BizHawk that allows two or more people to play a co-op experience by sharing inventory/ammo/hp over the network. This will work with vanilla versions of the games and also randomizers. https://github.com/TestRunnerSRL/bizhawk-co-op

This is an emulator hack that turns 1-player games into 2-player games by sharing in-game inventory over the internet. https://github.com/mcclure/emu-coop (snes 9x)

QUsb2Snes is a websocket server that provide an unified protocol for accessing hardware/software that act like a SNES (or are a SNES). A classic usage is to use the FileViewer client to upload roms to your SD2SNES. But it allows for more advanced usage like reading/writing the memory of the SNES. https://github.com/Skarsnik/QUsb2snes (real SNES hardware)

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Setup

There are two different methods to install.

• Run the PowerShell script, Download it here: bizhawk-co-op.ps1. I suggest placing it wherever you want to install Bizhawk. To install it, right-click it and select "Run with PowerShell". This will download & install a fresh copy of BizHawk with all the required files in their correct locations.
  OR
• You can manually download the files, install and move them in the correct locations as described below.

You will need the following:

• (1) BizHawk 2.3

• The co-op script should be compatible for Bizhawk 1.12.0+ and 2.2.2+

• (2) BizHawk prerequisite installer (run this)
• (3) luasocket
• (4) bizhawk-co-op

• If you are running OoTR 3.0 Release, replace the file, bizhawk-co-op/ramcontroller/Ocarina of Time.lua with this version of the file: bizhawk-co-op/ramcontroller/Ocarina of Time.lua

Directory structure

The locations of files is very important! Make sure to put them in the right place. After unzipping BizHawk (1), you should be able to find the executable EmuHawk.exe, we will call the folder containing it BizHawkRoot/.

First, in luasocket (3), you should find three folders, a file, and an executable: lua/, mime/, socket/, lua5.1.dll, and lua5.1.exe. Place mime/ and socket/ in BizHawkRoot/, and place the contents of lua/ in BizHawkRoot/Lua/. Place lua5.1.dll in BizHawkRoot/dll/. You do not need lua5.1.exe.

Next, the bizhawk co-op distribution includes two important things: the main lua script bizhawk co-op.lua and a folder bizhawk-co-op/. Place both of these in BizHawkRoot/.

Once this is done, your directory structure should look like this:

(1) BizHawk-2.3/ 
(4)   bizhawk-co-op/
(1)   dll/
(3)     lua5.1.dll
        ...
(3)   mime/
        ...
(3)   socket/
        ...
(1)   Lua/
(3)     socket/
(3)     ltn12.lua
(3)     mime.lua
(3)     socket.lua

(4)   bizhawk co-op.lua
(1)   EmuHawk.exe
      ...

bizhawk-co-op Configuration

If using Bizhawk 2.2.2+, go to Config -> Customize... -> Advanced and set Lua Core to Lua+LuaInterface. NLua does not support LuaSockets properly. After changing this setting, you need to close and restart the emulator for the setting to properly update.

Once you have everything else properly set up, you can run the bizhawk-coop script to do some final setup before syncing and playing a game. To run the script in BizHawk, go to Tools -> Lua Console, and the Lua Console should open up. At this point, I suggest checking Settings -> Disable Script on Load and Settings -> Autoload. The former will allow you to choose when to start the script after opening it instead of it running automatically, and the latter will open the Lua Console automatically when you load EmuHawk.

Next, go to Script -> Open Script... and open bizhawk co-op.lua (it should be in BizHawk-2.3/ root.) Make sure you are running a game, and then double click bizhawk co-op (or click it and then press the green check mark) to run the script. The window has the following important configurations:

• Host IP and Port: The client should set the IP to the host's IP address, and both players must choose the same port number. The host will need to enable port forwarding on the chosen port, and will have to make sure their firewall is not blocking BizHawk. As for setting up port forwarding, Google is your best friend.

• Note: This may not apply to everyone but make sure you don't have UPnP IGD enabled on your router, this setting could prevent you from joining a host or hosting a room.
• Port forwarding alternative: "In the event you do not have access to your router to apply port forwarding, try using the program called, "Hamachi". This program allows you & others to connect to one another as if you are on the same LAN (Local Area Network). Don't let the subscription stuff scare you on their site, all you need is a free account!"

• Game Script: Be sure to choose the appropriate game when creating the room or joining a room.

Make sure to click Save Settings, and you should be ready to play!

Syncing with bizhawk-coop

The host should first enter their name and password and click Create Room to host. Then the clients should click Refresh and select the appropriate room, enter their name and the room password, and click Join Room. The bizhawk-co-op script will run some consistency checks on your configurations to make sure you are running the same code. If these all passes then the players will be connected. So if you encounter any issues connecting to one another, make sure all players possess an up to date script.

• Lock Room: The Host can click this to prevent prevent anyone else from joining the room.
• Leave Room: Click this to cleanly close down the connection. Closing the Lua Console or BizHawk directly can result in issues reconnecting for some time.

Supported Systems

bizhawk-co-op will only run on a Windows OS because of BizHawk support.

Credits

Created by TestRunner.

BizHawk, Lua, Luasocket, and kikito's sha1 script. Lua, luasocket, and sha1.lua all fall under the MIT license.

Issues

If you have any problems with the script (and restarting BizHawk does not fix them,) contact me (TestRunner (@Test_Runner) on Twitter or on Discord. You can also submit an issue here on the GitHub.