Module gemini_engine::gameloop

The gameloop is one of Gemini’s most important features. If you read the Quick Start guide, you’ll have seen that the example there didnt have a fully written gameloop. When you begin building larger projects with Gemini, this is what your code should look like

use gemini_engine::gameloop;

const FPS: f32 = 30.0;

fn main() {
    // --initialisation--
    let mut frame_skip = false;

    loop {
        let now = gameloop::Instant::now();
        // --clearing views and all necessary logic--

        if frame_skip {
            frame_skip = false
        } else {
            // --all blitting and rendering goes here along with any visual logic--
        }

        let elapsed = now.elapsed();
        frame_skip = gameloop::sleep_fps(FPS, Some(elapsed));
    }
}

Writing your code like this ensures that it wont affect the game’s intentional speed too much, and also makes it easy for you to benchmark your game’s speed with something like println!("Elapsed: {:.2?}µs", elapsed.as_micros()); after let elapsed.

You can use the fps_gameloop! macro to achieve the same result. Read about how to use it in the fps_gameloop! documentation

Re-exports

• pub use with_root::MainLoopRoot;

Modules

• with_root
  An object oriented approach to the gameloop, separate from fps_gameloop!. Read the MainLoopRoot documentation for more info

Structs

• Duration
  A Duration type to represent a span of time, typically used for system timeouts.
• Instant
  A measurement of a monotonically nondecreasing clock. Opaque and useful only with Duration.

Functions

• sleep_fps
  Sleep for a single frame at the declared FPS, subtracting the input Duration to account for any time spent processing the frame. Returns a bool value depending on whether or not the frame took longer to render than the intended fps