A Practical Architecture Design For MMO Casual Game

Ngô Thái An

Content

• Happy Me• Architecture Overview• Architecture Detail

Object Management SystemServer-Client Data SynchronizationNetwork Message Dispatching System

Happy Me

Happy Me

• MMO casual game• Room-based active server• Web-based Unity3D client• Run on social platform

In-game screenshots

About technical team

• 3 system and framework developers• 4 game developers• 12 months of development

Architecture Overview

MMO game physical architecture

Database

Game Servers

Client

Internet

Game data, logic, presentation

Server Side Client Side

Game Logic

PresentationOf A Player

PlayerData

PlayerData

PlayerData

PresentationOf A Room

MODEL

CONTRO-LLERVIEW

Which design to adapt ?

A minimalist game system

Object Management

System

Network Message

Dispatching System

Auto Synchronization Framework

REQUIRE

REQUIRE

MAKE OUR LIFE EASIER

Initial requirements

• Object management system MVC design pattern Dynamic data

• Auto synchronization framework Truly automatic («Set» and forget style) Synchronize the delta difference only

• Network message dispatching system Custom structure message Easy to register messages and invoke

handlers

Object Management System(MVC Design)

Overview diagram

Model

View

Controller

(gameplay logic)

Database

Network Message

s

View

Controller

(graphic logic)

Server Side

Client Side

Unity3D

3D Models

Database

Model

MVC objects mapping

Model

View

Controller

Game Objects

Object Views

Game Logic

Modules

Rooms

Detail diagram

Game Objects

Object Views

Game Logic

No-SQL(Storage)

Network Message

s

Object Views

Graphic Logic

Server Side

Client Side

SQL(Ranking,

Log)

Database

Game Objects

Modules Modules

Rooms Rooms

General purpose base object

Object

Rooms

ObjectViews

ModulesGame

Objects

The “Object” requirements

• A container of properties• Serialize to and deserialize from JSON• Hierarchy relationship (parent-child)

Object dynamic properties

Object

Guid

Property 1Property 2

Property Meta Data

• Tags• Persistent• Client transfer

• Type• Long

• Name• “property 2”

• Version• 568

Define the properties

The object tree

Object

Unit

GameObject

DataObject

Player

DecoItem

Pet

UseItem

ClothItem

Item

Quest

Job

PlayerView

DecoView PetView

ObjectView

Module

MainGame

Authen

HomeDeco

SyncData

Room

Lobby Public Personal

Object Manager

ResultPros• MVC design pattern practice• Fully customizable property system• Manage game world into one single

system

Cons• Challenge to manage huge number

of objects

Auto Synchronization Framework(Server <-> Client)

Synchronization concept

ServerRoomPlayer.Position = (10,

20)

Player.OnUpdatePosition(10, 20){ model.MoveTo(10, 20);}

Client

Duties of a room

SynchronizationScheduler

OtherScheduler

s

MessageProcessor

ROOM

• Process messages from clients

• Send or broadcast messages to clients

• Synchronize data changes between server and clients

• Update status• Other duties…

Thread pool workers

Personal Room

Coffee Room

Downtown Room

Sync

Other

Sync

Thread Pool

Other

Sync

Other

Sync

Sync

Other

ROOMS

TASK QUEUE

S

WORKERS

Thread

Schedulers 1 second

SYNCHRONIZATIONSCHEDULER

OTHERS SCHEDULER

1/10 second

Other Task

Sync Task

Sync Task

Other Task

Sync Task

Other Task

TASK QUEUE

WORKER

Object change-set

ObjectPosition

Energy

Gold

Change Set

SYNCHRONIZATIONSCHEDULER

SetProperty(Position, (1, 2))

Sync Task

ResultPros• Automatic synchronization property

changes• Optimal data transfer• Best use for active server game

Cons• Overhead to determine what has

changed since last sync.

Network Message Dispatching System

Custom message structureLogin- Usernam

e- Password

Synchronize- Type- Propertie

s

Buy Item- ItemType- Quantity

Chat- Message

RequestFriend- FriendGuid

Serializer(Thrift, Protobuf, Json,

XML)

Network package

Encryption

Message factory

Server

Send

Client

Receive

Serialize

Deserialize

Login- Username- Password

Login- Username- Password

OnAuthen

OnMove

OnRun

LoginAuthenMoveRun

Message Handlers

OnLogin

ResultPros• Meaningful message by define

custom structure• Familiar usage as common GUI

system (MFC, WinForm)• Share message definition between

server and client• Easy to apply encryptionCons• Unknown

Conclusion

• Seamless MVC framework across server and client

• Address the most common difficulty in design active server : the synchronization

• Base framework environment for adapting any gameplay

Q&A