Gallery

3D Multiplayer Demo with Phoenix Channels + Three.JS

3d.demo.mp4

Concept

The goal of this project is to leverage Phoenix's ability to build highly concurrent realtime applications to create a scalable 3D multiplayer game that doesn't need much server hardware to run.

Each player's web browser connects to a Phoenix channel via a websocket that will broadcast updates about the other players as they occur in realtime. Each player's browser renders those updates with Three.JS. Updates are processed every frame, resulting in a very low latency experience.

Sequence

sequenceDiagram
    actor You
    You->>/gallery: Hit endpoint
    /gallery-)Browser: Initialize Three.JS Scene
    Browser-)Gallery Channel: Join channel
    activate Gallery Channel
    Gallery Channel->>Gallery Channel: Create Player
    Gallery Channel->>PlayerCache: Cache player
    activate PlayerCache
    PlayerCache-->>Gallery Channel: Retrieve all cached players
    deactivate PlayerCache
    Gallery Channel--)Browser: Send cached player data
    deactivate Gallery Channel
    Browser->>Browser: Register players, prepare canvas, start rendering
    Browser-)Gallery Channel: Ready up
    activate Gallery Channel
    Gallery Channel--)Browser: Broadcasts your player to everyone else
    deactivate Gallery Channel
    

    Note over /gallery,PlayerCache: Keydown Events
    Browser->>Browser: Handle keydown events
    Browser-)Gallery Channel: Update player
    activate Gallery Channel
    Gallery Channel->>PlayerCache: Update player
    Gallery Channel--)Browser: Broadcasts your player updates to everyone else
    deactivate Gallery Channel


    Note over /gallery,PlayerCache: Disconnect
    Browser-)Gallery Channel: Disconnect
    activate Gallery Channel
    Gallery Channel->>PlayerCache: Delete from cache
    Gallery Channel--)Browser: Broadcasts disconnect
    deactivate Gallery Channel

Getting Started

These instructions will get you a copy of the project up and running on your local machine for development and testing purposes.

Prerequisites

This project uses ASDF to manage Erlang, Elixir, and Node versions

Installing

OSX

Postgres isn't being used (yet) so feel free to skip those steps.

1. Add and install plugins with ASDF

asdf plugin add erlang https://github.com/asdf-vm/asdf-erlang.git
asdf plugin add elixir https://github.com/asdf-vm/asdf-elixir.git
asdf plugin add nodejs https://github.com/asdf-vm/asdf-nodejs.git
asdf install

2. Install postgres

brew install postgresql@15
brew services restart postgresql@15  

3. Install psql

brew install libpq
echo 'export PATH="/opt/homebrew/opt/libpq/bin:$PATH"' >> ~/.zshrc

4. Setup postgres user

$ psql postgres
postgres=# CREATE USER postgres SUPERUSER;
# DB might already exist, if so, you're good
postgres=# CREATE DATABASE postgres WITH OWNER postgres;

Running

To start your Phoenix server:

• Run mix setup to install and setup dependencies
• Start Phoenix endpoint with mix phx.server or inside IEx with iex -S mix phx.server

Now you can visit localhost:4000/gallery from your browser.

Learn more

• Official website: https://www.phoenixframework.org/
• Guides: https://hexdocs.pm/phoenix/overview.html
• Docs: https://hexdocs.pm/phoenix
• Forum: https://elixirforum.com/c/phoenix-forum
• Source: https://github.com/phoenixframework/phoenix

License

This project is licensed under the MIT License - see the LICENSE file for details