MMOPONGBrnoJS X - 7 April 2015

Vincent van Scherpenseel

Disclaimer

Please don’t laugh (too much)

Why?

• I wanted to learn NodeJS

• I love code related to networking

• I love retro games

• My love life was falling apart ;)

Ingredients

• NodeJS

• SOCKET.IO (v0.8.7) for networking

• jCanvas (v5.1) for simple canvas manipulation

• Webserver (Apache, Nginx, pick your poison)

• Open port 8080

“Architecture”

Server(dictator)

Player(slave)

Player(slave)

Player(slave)

Player(slave)

Server is a dictator

The server dictates:

• where the ball is

• where all players (pads) are

• when a collision has occurred

• when a goal has been scored

Player is a slave

The only thing that the player is allowed to do:

• request to move (more on that later)

• render the game

SOCKET.IO rocks

The game loopServer-Side

Collision detection

Moving the ballserver-side

client-side

client-side

The game loopClient-Side

Drawing assets

Moving the pads

Confession time

Why is network performance so horrible?

This is baaaaaaaaaaaaaaaaaaad

ServerPlayer Can I haz move?

ServerPlayer Yes, new coords:

The Right Way™

ServerPlayer

ServerPlayer DISCONNECT

My new coords:

if ( $distance > $possibleDistanceTraveledConsideringTime ) {

Thank you!Vincent van Scherpenseel

http://vincent.io/ @vanscherpenseel