WorldEngine

Highly configurable Socket.IO MMO game engine server suite. WorldEngine uses PostgreSQL for persistent storage. WorldEngine has been designed to contain as little game logic in itself as possible. All game entities, objects, and events should be configured and handled by scripts.

Scripting

Ideally, all game logic is written in JavaScript scripts to be interpreted at launch. Scripts can be used to make and register: item attribute presets, skills, packet actions, etc. Scripts can also hook on to event triggers to handle game events.

Game Ticks

The game thread handles timing of game ticks and is in charge of triggering the game_tick event. Ticks are timed to occur every 500±1ms. At the start of each tick, the game thread will attempt to execute and clear the action queue, then trigger the game_tick event. Game logic should ideally populate the action queue instead of executing the action directly.

game_tick Trigger Hook Example

// Writing your own Trigger
var Trigger = Java.type('com.worldstone.worldengine.trigger.Trigger');
var MyGameTickTrigger = Java.extend(Trigger, {
    resolve: function(attributes) {
        print(attributes);
    }
});

// Register MyTrigger with the TriggerController
var TriggerController = Java.type('com.worldstone.worldengine.trigger.TriggerController');
TriggerController.registerTrigger(new MyGameTickTrigger('my_game_tick_trigger', 'game_tick'));

Items

A unique object with attributes that represents an object that can interact with inventories, character equipment, and other ItemContainers.

Item Script Usage Example

// Registering an attribute preset
var HashMap = Java.type('java.util.HashMap');
var ItemFactory = Java.type('com.worldstone.worldengine.game.item.ItemFactory');
var presetMap = new HashMap();
presetMap.put('name', 'my_item');
presetMap.put('display_name', 'My Item');
ItemFactory.registerPreset('my_item_preset', presetMap);

// Getting an Item instance with an attribute preset
var ItemType = Java.type('com.worldstone.worldengine.game.item.ItemFactory.ItemType');
var myItemInstance = ItemFactory.getItem(ItemType.BORING, 'my_item_preset');

Triggers

Triggers are used to pass events between WorldEngine and scripts. There are some events that are triggered by WorldEngine itself, but events can also be triggered by scripts.

Trigger Script Usage Example

// Writing your own Trigger
var Trigger = Java.type('com.worldstone.worldengine.trigger.Trigger');
var MyTrigger = Java.extend(Trigger, {
    resolve: function(attributes) {
        print(attributes);
    }
});

// Register MyTrigger with the TriggerController
var TriggerController = Java.type('com.worldstone.worldengine.trigger.TriggerController');
TriggerController.registerTrigger(new MyTrigger('my_trigger', 'some_event'));

// Trigger an event
var HashMap = Java.type('java.util.HashMap');
TriggerController.triggerEvent('some_event', new HashMap());