Multiplayer

From ZDoom Wiki

Multiplayer is a term used to represent a game with multiple players. This can be in a competition style, such as deathmatch, or a cooperative style of play against the game's monsters.

Deathmatch is a multiplayer game style pioneered by Doom in which players face off against each other, connected to a common area via a network.

• A point, called a frag, is granted to a player whenever he or she kills an opponent.
• Upon death, players restart at a random deathmatch start.
• Players spawn with all keys, and keys are never placed on the map (there is currently no clean way to circumvent this).

Cooperative gameplay, often referred to as co-op or coop, is a multiplayer game mode in which human players cooperate against a given game's monsters. Cooperative play is the default game mode if the -deathmatch parameter is not specified at the command line.

ZDoom uses TCP/IP (UDP) for all network play. The game state is tracked on a peer-to-peer system, unlike ZDaemon, CSDoom, or Skulltag which are much better suited to larger-scale games because of their focus on improved networking efficiency and client-server architecture.

Multiplayer games must be started either from the command line or from a launcher of some sort. A sample set of command lines follows:

zdoom -host 2 -warp 01 -skill 4
zdoom -host 2 -deathmatch 1 -warp 01
zdoom -join 192.168.0.1

For more information, please see Command line parameters.

• The first command line tells the computer to host two nodes (itself and one other), warp immediately to MAP01, and set the skill level to Ultraviolence.
• The second line also hosts 2, uses the default skill level ("Hurt Me Plenty"), and sets the game mode to deathmatch.
• The third command line joins a server hosting any kind of game at the IP address specified.

A person joining a game does not need to specify any additional parameters aside from loading any custom WADs or DeHackEd patches that the host is using. Using custom levels and patches that are not in use by everyone in the game will cause consistency failures and the game will desynchronize.

*Note: If you feel uncomfortable using the command line frequently, you may enter the text into any text editor and save the file with a .bat extension. This will create a file you can simply double-click to launch a game with the commands you entered.

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If you want to play online, you can use Doom Connector or the IDE to find opponents and to set up a game by simply setting the settings with a mouseclick and then launch it. This system also works if you want to play over LAN, but you do need an internet connection.

There are three ZDoom-based ports that have improved networking code, specialized for online multiplayer:

• CSDoom is no longer being maintained. It was based on ZDoom's version 1.22 source code and had its own network code. CSDoom was the first client/server multiplayer port.
• ZDaemon is the continuation of CSDoom with a new guy handling the project and a lot of new code as well. The current version of ZDaemon was based on a much newer ZDoom source code and it therefore supports many of ZDoom's newer map-making features.
• Skulltag, not just a multiplayer-oriented source port, but full multiplayer mod with new weapons, bots with their own set of unique character traits, new levels designed to make use of the special features available in that port, and more.