game-loop 0.2.0

Game Loop

A Rust crate that implements a frame-rate-independent game loop. The code is based on "Fix Your Timestep!" and is extremely lightweight with no dependencies.

Usage

use game_loop::game_loop;

fn main() {
  let game = YourGame::new();

  game_loop(game, 240, |g| {
    g.game.your_update_function();
  }, |g| {
    g.game.your_render_function();
  });
}

The value 240 is the number of updates per second. It is not the frame rate. Instead, the render function is called as quickly as possible, though you can slow it down if you wish. This may be useful if vsync is enabled or to save power on mobile devices. One way to slow it down is with std::thread::sleep.

The g closure argument lets you access your game state which can be anything you like. You can also access the game loop's running time, how many updates there have been, etc. It also provides a blending_factor that you may use in your render function to interpolate frames and produce smoother animations. See the article above for more explanation.

Example

There's a Game of Life example that shows how to use the crate. You can run it with:

cargo run --example game_of_life

License

MIT