Commands

Introduction

In Lugdunon, commands are what drive the game state. Any action that occurs should result in a command being generated to be handled in the update loop. Commands are also the method in which the client and server communicate. Commands are specific to a given server, and are loaded from the classpath based on their inclusion in the WORLD/etc/commands.json file.

Commands are referenced in code by their unique command id. Programmatically, commands are referenced by a short int opcode, meaning that commands are limited to at most 215-1 (32767). With the exception of of net.lugdunon.command.core.ErrorCommand, net.lugdunon.command.core.GetServerStatusCommand, and net.lugdunon.command.core.ConnectToServerCommand the opcode for a command is dynamically assigned at server start and should never be relied upon to remain the same value across server instances.

A command exists as a single instance, loaded and initialized upon server start for server-side commands and upon client connect for client-side commands. Commands are referenced in code via their command id, a unique string that identifies a specific command. How to call commands on the server and client will be examined towards the end of this article.