Crysis Coop

The Crysis (2007) single player campaign in co-op for 2–4 players, built as a Crysis mod (C++ game DLL, Lua and configs).

• The host plays the campaign exactly as in single player: AI, story scripts, cutscenes, objectives, level to level.
• Progress is saved at the campaign's checkpoints, on the host's PC and in the cloud; coop_continue picks the game up there, hosted by any player of the campaign. Every new game is a campaign of its own.
• Friends join over the internet with a short code that stays the same (coop_join 382615). Nobody has to open or forward ports. When the host's game restarts (a checkpoint loads, a new game), the friends join again by themselves.
• The game connects the players directly when it can (UDP hole punching), otherwise through a small relay server.
• No friends around? One checkbox in the co-op menu starts an AI companion: a light second copy of the game in the background, played by a bot, or by an AI agent through MCP (CrysisCoop.exe -coop_mcp).

Русское описание для игроков: Mod/README_RU.md

Install and play

Download the latest release, extract it and run install.bat, or run this in PowerShell:

powershell -ExecutionPolicy Bypass -c "irm https://github.com/SeniorStackOverflow/crysis-coop/releases/latest/download/install.ps1 | iex"

• Host: start the Crysis Coop shortcut (the launcher CrysisCoop.exe in the game folder), Multiplayer → Co-op game (it replaces Quick game; Russian: Сеть → Кооперативная игра), then New campaign or Continue.
• Friend: Multiplayer → Co-op game → Join a friend, the code the host sees, Join.
• In the game, Esc → Co-op game: the code, the players, saving and going back to a checkpoint, leaving.
• Console commands (coop_host, coop_continue, coop_join <code>...) do the same without the menu.

Needs Crysis 1.2.1 (GOG, Steam, EA; DVD + patches) on Windows 8 or later, or on Linux under Wine (install_linux.py). Each player needs their own copy of the game. The player guide is in Mod/README.md.

How it works

Crysis 1 has no co-op. The mod runs the single player levels as network maps.

• Server side. The host's game runs the full single player simulation:
  • the AI system (the engine switches it off in network games);
  • the level flow graphs and story;
  • the gamerules of the campaign.
• Clients. They receive what the stock network code does not carry:
  • AI actions and shots;
  • cutscenes and HUD/flow effects (mirrored flow nodes);
  • objectives, map markers, usable objects;
  • player placement by scripts;
  • nanosuit modes.
• Campaign. Level changes keep everybody connected, and inventories and campaign state carry over.
• Saving.
  • At each checkpoint the host saves a single player savegame of the whole level. It is CryAction's own save, made in single player mode for a moment, without the other players.
  • Every player's equipment goes to the campaign's progress file, keyed by the player's relay id (not by the in-game name, which depends on the order of joining).
  • coop_continue hosts that level and loads the save into it. It then puts the server back into shape for network play (player limit, clocks), and the friends join (CoopSave.cpp).
  • Checkpoints are also uploaded to the relay server (CoopCloud.cpp), so every player of the campaign may carry it on.
• Co-op menu. A panel drawn with IUIDraw over the Flash main and in-game menus (CoopMenu.cpp). It takes the menu's mouse and keys before the Flash menu does. The HUD shows the host's code for a while.
• AI companion. With the checkbox on (coop_companion 1), the host's game starts a second Crysis.exe with its own profile (CoopAgent.cpp). It is a normal client: it joins the host through a small UDP relay on this PC, and the host sees it as a player. The game is made light (no renderer at all: r_Driver NULL, no sound, 20 fps, low CPU, I/O and memory priority, other CPU cores, no window) and ends with the host. A bot plays its soldier: it steers the player's input, so the stock game code does the walking, shooting, vehicles and revive. CrysisCoop.exe -coop_mcp (Launcher/Mcp.cpp) is an MCP server over stdio that turns an AI agent's tool calls into requests to a small TCP bridge in the companion's game (127.0.0.1, the port is in %LOCALAPPDATA%\CrysisCoop\companion\agent.port). The agent sees text (observe; screenshot only when the companion's game renders); the bot does the aiming and walking between its orders.
• Players and codes. Every player has a random key made once. The relay keeps only its hash and gives each host a permanent code. The host tells the relay when his game restarts, and the friends' tunnels wait and reconnect their games (CoopRelay.cpp).

The files:

Path
Code/Mod/	the game DLL (Coop.dll), based on the CryENGINE 2 Mod SDK game code. The coop work is mostly in CoopAI.cpp, CoopRelay.cpp, CoopSave.cpp, CoopCloud.cpp, CoopMenu.cpp, CoopRevive.cpp, CoopAgent.cpp (the AI companion), Nodes/CoopFlowNodes.cpp, plus hooks in the stock files
Code/CryEngine/	engine interface headers from the SDK
Mod/	the mod's Lua scripts and configs (copied to Mods/Coop)
Launcher/	CrysisCoop.exe: starts the game with the mod, checks what the mod needs first, and updates the mod by itself (Update.cpp: signed manifest, from the VPS or GitHub); CrysisCoop.exe -coop_mcp is the MCP server for AI agents (Mcp.cpp)
Installer/	install.ps1, install.bat, uninstall.ps1; install_linux.py for Linux (the game under Wine)
Relay/	the relay server (Python, no dependencies: tunnel, codes, cloud checkpoints) and its deployment
tools/	package.ps1 (release archive and signed update), publish_update.ps1 (update to the VPS), update_key.ps1 (the release key), lua_check.py

The co-op levels are not in this repository or in the releases: the installer builds them from the player's own game files.

Building

Requirements:

• Visual Studio 2019 or later, or its Build Tools, with the "Desktop development with C++" workload.
• The repository cloned into the Crysis folder, e.g. C:\GOG Games\Crysis\crysis-coop.

build_coop.bat

This builds the 32-bit Coop.dll and the launcher CrysisCoop.exe, and copies them, together with Mod/, into ..\Mods\Coop (the launcher also into the game folder). The launcher updates this copy like any other only when a newer release than the build is out (keep your build's version ahead, or use -coop_noupdate). Run the game with ..\CrysisCoop.exe, or Bin32\Crysis.exe -mod Coop (C1-Launcher is required). Edit scripts and configs in Mod/, not in Mods\Coop.

tools\package.ps1 makes the release archive in dist\, and the automatic update in dist\update-v<version>\ (signed with the release key from tools\update_key.ps1, kept on the publishing PC only). tools\publish_update.ps1 puts the update on the VPS; every player's launcher installs it at its next start. The GitHub workflow builds the DLL and the launcher and attaches the archive to a release when a v* tag is pushed.

The relay server: see Relay/README.md. The mod uses wss://crysis.46-225-103-75.sslip.io/ by default. Point the coop_relay cvar at your own relay to use that instead.

Credits

• c1-mod-sdk by ccomrade: the CryENGINE 2 Mod SDK set up for modern MSVC, on which this project is built.
• C1-Launcher by ccomrade: required to run the mod.

License

The game code is based on the CryENGINE 2 Mod SDK and is distributed under its license, LICENSE.txt. Free distribution only, and a legal copy of Crysis is required.

This site is not endorsed by or affiliated with Crytek or Electronic Arts. Trademarks are the property of their respective owners. Game content copyright Crytek.