[−][src]Crate rusty_sword_arena

💡 Did You Know? You can generate your own, offline version of this document by running this command in your own clone of the repository.

cargo doc --lib --no-deps --open

Other Tutorial References

Rusty Sword Arena - Game Design

Rusty Sword Arena is a networked, 2D, top-down, arena combat game. A server implementation and shared library is provided. Your task is to implement a game client in Rust using the provided shared library and the game design details below.

Note that while significant effort has been put into making the server robust and unlikely to crash, there has consciously been very little effort towards security, or pretty much any proper game engine architecture. In other words, this is a great way to learn Rust and have some fun at the same time, but this in no way pretends to be a substitute for a real game engine™ like amethyst or ggez. 😉

Basic Gameplay

The basic idea of the game is you are presented with the top-down view of a person (circle) in an arena (your window) who can swing his weapon (a rusty sword) in a circle. You can face any direction you like, turning is instant as far as the server is concerned. You can move in any direction (which is not instant, the server implements some rudimentary movement physics) and attempt to attack other players with your sword. If another player is within the radius of your sword reach when you attack, they will be hurt and their health will go down. You will be limited to 50% movement speed while attacking, so try to time your attack to when they will be successful.

You start with some health. When you are hit, you lose health. When the health runs out, you die and the person who killed you gets a point. After a respawn delay, you respawn with full health. If you attempt to run from the arena, you are likely to be eaten by a grue. Being eaten by a grue causes you to lose a point, but there is no point penalty when another player kills you.

Preparation

First, you should follow the instructions on the readme to install some dependencies. Then come back here and keep going.

Creating Your Game Client

These are all things we will do together in the tutorial. Feel free to get ahead of the group if you can!

  • Pick a name for your client and create a Rust crate. Hint: use cargo
  • Obtain the player's desired name and the host to connect to.
    • One easy way is to get the name and host from the command-line.
    • See args for the code part.
  • Add rusty_sword_arena as a dependency in your Cargo.toml file.
  • Create a ConnectionToServer using the host
  • Use the ConnectionToServer to join the game.
    • If the join fails, print out the error message and quit the program.
    • Keep the player id that is returned so you can tell which player you are.
  • Use the ConnectionToServer to get a GameSetting. If GameSettings.version does not match the rusty_sword_arena::VERSION you are using, then you are using a different version of rusty_sword_arena than the server, and you should abort the game and update your Cargo.toml to use the same version.
  • Use the Audio struct to play sound effects. You can use these free placeholder sounds either individually or zipped up if you like, or record or create your own sounds! Files can be MP3, WAV, Vorbis or Flac. (Or you can skip sounds altogether, really).
  • Create a Window
  • Create a PlayerInput to keep track of player input.
  • IN YOUR MAIN GAME LOOP...
    • Gather GameEvents from the Window, handle all the possible events, including updating your PlayerInput based on what you see.
    • Get all the pending GameStates from the server.
      • FOR EACH GAME STATE (which represents the state of one frame)
      • Process all the PlayerStates into some local collection(s) that represent the client's current view of players.
    • For each PlayerState, process any new PlayerEvents to play sounds or update
    • Loop through your local state storage and draw a frame that represents the latest state of the players. ...

Challenges!

Here are some things we will NOT do together in the tutorial. If you are ahead of the class, or want to keep going after the class, here's some challenges you could take on!

  • Every GameState includes a HighScores struct. Why not do something with it? You could just print it to the console every once-in-awhile, or do something more interesting.
  • Your player might sometimes appear underneath other players if they overlap. Make your player always render on top.
  • Which player is yours!? Add some visual indicator so you can easily tell your player apart.
  • Multiple players from one client - The server and networking protocol do not prevent a single client from adding multiple players to the game. Create some way to divide the keyboard/mouse input up among two or more local players who will play through the same client.
  • AI - Who says a human has to do the playing? The server is giving you all the information about all the players's states. Use that information to develop an AI player who plays by himself.
  • RTS - Who says you have to control everything little movement? Combine one or both of the above challenges to implement a real-time strategy interface, where you direct one (or more) players controlled by your client to achieve a goal (move somewhere, attack things, run away, etc) and then your controlled players autonomously attempt to achieve that goal until you specify otherwise.
  • Better Graphics - Improve on the graphics. Either make better use of the provided shapes to indicate more of what is going on, or dig into the RSA gfx.rs module and augment it with new and better graphical capabilities. Health indicators sure would be nice.
  • Better Sound Effects - Make some decent sound effects of your own!
  • Improve Rusty Sword Arena Itself -- Fork Rusty Sword Arena. Add features, or fix bugs in the server.
    • Improve the reference client implementation.
    • Port the graphics subsystem from OpenGL to Vulkan.
    • Add more graphics primitives (rectangles for healthbars, for example).
    • Add the ability to render text.
    • Port the network subsystem from ZeroMQ to nanomsg.
    • Upgrade the audio subsystem. Add a way to play looping music alongside the sound effects, or to adjust the volume. Read up on rodio, the low-level library we use to process and play audio.
    • Update the documentation to be clearer, more comprehensive, and have more useful links.
    • Add support for Game Modes (Teams? Capture the flag?).
    • Add multiple weapon types and random weapon drops to pick up.
    • Add the ability to Parry (you can try to attack OR parry - a successful parry causes the attacking player to have a much larger delay than usual before the next attack attempt).
    • Add player collision.
    • Create an issue if you have ideas you want to discuss, or need help.
    • Create a Pull Request if you would like feedback on your code, or if think your change is ready to contribute back to the main project.

Modules

audio

A module for reading and playing audio files

game

Everything in the game module is shared by the server and the client

gfx

The graphics module that will be used by your client The OpenGL window is (-1.0, -1.0) in the bottom left to (1.0, 1.0) in the top right.

net

The networking module that will be used by your client

timer

A timer module for general use

Constants

VERSION

The current version number. Your client should check this against the version the server sends in GameSettings