Poké Versus

Introduction

Poké Versus is a simple 1v1 pokemon game I decided to make as my websocket project for a university class. Each player uses a website to connect to the server via a websocket. Server then connects two players and acts as a middle ground passing messages between them. Server can handle up to 256 concurrent games.

Frontend is written in Svelte. My language of choice was TypeScript. To not have to deal with plain CSS I used TailwindCSS. Game scene is rendered with Three.js and Svelte Cubed.

Backend is written in Kotlin + KTOR.

How to run

1. Frontend Server

• Enter "frontend" directory

• Install dependecies

npm install

• If game will be played on multiple machines set server's IP in config.ts

• Run on local machine

npm run dev

2. Backend Server

Open project in Intellij IDEA and run

Disclaimer

This implementation is extremely unsecure. There is no server side validation done so for the whole system to work both players will have to play fair.

This is by no means a finished game as there is no animations, sounds and it is even missing some of the core features like swapping to a different pokemon.

It was my first Svelte project so frontend is quite a mess.

I do not own any of the assets used.

Communitcation protocol

Commonly used values

Name	Meaning	Possible Values
Message type	Value specyfing which message was received	0..4
Pokemon ID	Index specifying a species of pokemon	0..24
Game ID	Number used to differentiate games	0..255
Player Number	Player with number 1 starts	0 or 1

Join Game Message (type = 0)

Client sends this message when he wants to start a game. Message contains a list of chosen pokemon IDs.

Byte	Content
0	Message type
1	First pokemon ID
2	Second pokemon ID
3	Third pokemon ID

Opponent Joined Message (type = 1)

Server sends this message to both clients provided they both sent "Join Game" message first. Message contains a list of their opponent's pokemon IDs.

Byte	Content
0	Message type
1	First pokemon ID
2	Second pokemon ID
3	Third pokemon ID
4	Game ID
5	Player Number

Attack Message (type = 2)

Client sends this message to server after chosing an attack. If this attack will cause the player to win then Game Won byte is set to 1. Using this server will be able to clean up after game.

Byte	Content
0	Message type
1	Game ID
2	Amount of damage
3	Game won
4	Player Number

Receive Damage Message (type = 3)

Server sends this message to client after receiving "Attack" message from that player's opponent.

Byte	Content
0	Message type
1	Amount of damage

Reconnect Message (type = 4)

Clients sends this message to server after website is reloaded so server will update connection.

Byte	Content
0	Message type
1	Player Number
2	Game ID