Relay Pong

Title

Relay Pong, a Pong-Inspired Web Application

Abstract

This project concerns the development of a variant of the classic videogame Pong, in the form of a web application playable via browser, allowing several players to engage in team-based competitive gameplay. The primary objective of the project is to explore real-time distributed systems.

The traditional Pong is a simulation of table tennis. During a game, two players compete by controlling one bar each. The players can use the bars to hit a ball, scoring points when the ball surpasses the opponent’s bar. The goal of the game is to score a set number of points before the opponent.

In the proposed variant, called Relay Pong, the game is no longer limited to just two players. During a game, two teams, each with at least one player, compete by controlling one bar per team. Team members take turns controlling their team’s bar, aiming to score a set number of points before the opponent team.

The initial goal of this project is to develop a proof-of-concept of the described service, essentially a prototype demonstrating the feasibility of the system. The service adopts a client-server architecture, where the server manages the true state of a game, shared with the clients. Clients transmit events to the server, reflecting players’ intentions, thereby updating the game state accordingly.

Real-time communication is achieved using the WebSocket protocol, enabling efficient bidirectional exchanges with low packet overhead. Additional aspects of interest include the logical model employed for representing a game, the dynamics governing the evolution of the game, and the synchronization between the players and the game server.

Demo

Here follows a demo of the game from the perspective of four different players, connected to the only available game server, using a static configuration for the match. The demo shows:

1. Four players joining the only available game server, readying to play;
2. The host of the lobby starting the game;
3. The evolution of a game with each player controlling their team’s bar (a bar is controlled by a player if it has a white mark in the middle);
4. The host and another player disconnecting during the game;
5. The new host and the other player continuing the game until termination, with the state of the game visible.