Networked GraphicsBuilding Networked Virtual Environments and Networked GamesChapter 2: One on one (101)

BOIDS

Three Forces Acting on a Boid

Cohesion Alignment Separation

Pi

Vi

A

P’i

V’i

At time t At time t+t

One Time Step of a Boid

Data Model

Simulation

Renderer

10101001111001001010101111011001......

Software

Client

DISTRIBUTED BOIDS: CONCEPTS

Data-Push

Client BClient A

Client A Client B

Data-Sharing

Client BClient A

Data-Coupled

DISTRIBUTED BOIDS: IMPLEMENTATION

Data Model

Simulation

NetworkRenderer

10101001111001001010101111011001......

10101001111001001010101111011001......

Software

ModemClient

Router

RouterRouter

Router

Software

ModemClient

Boids Implementation

Data model

Local Flock

Remote Flock

Screen (Renderer Output)

Network

Internet

Router

RouterRouter

Router

Simulation

Create socket local port X_socket =

DatagramSocket();

Read packet_packet =

_socket.read()

Write packet to remote address and port

_socket .write(_packet)

Close_socket

Write packet to remote address and port

_socket .write(_packet)

Read packet_packet =

_socket.read()

Close_socket

Create socket local port X_socket =

DatagramSocket();

Create Datagram Packet to receive and send

_packet = DatagramPacket();

Create Datagram Packet to receive and send

_packet = DatagramPacket();

Create socket to listen to requests on local port X

_listenSocket = ServerSocket();

Wait for incoming connection requests

_connectionSocket = _listenSocket.accept();

Read messages on_connectionSocket

Write messages on _connectionSocket

Close_connectionSocket

Connect to remote address and port_clientSocket =

_Socket();

Write messages on_clientSocket

Read messages on _clientSocket

Close_clientSocket

Setup streams_connectionSocket

Setup streams_connectionSocket

REFLECTION

X

ClientA

t

X

ClientB

t+tNetwork

Boidi Boidi

wall clock time wall clock time

X

wall clock time

ClientA

t

X

wall clock time

ClientB

t+tNetwork

Boidi Boidi

t+tNetworkt

Boidj Boidi

t

X

wall clock timeClientA

t

X

wall clock time

ClientB

tNetwork

Boidj

Boidi

tNetwork

Boidj

Boidi

a) At time t b) At time t+tNetwork

c) At time t+2.tNetwork

ClientA ClientB ClientA ClientB

ClientA ClientB