readme.md

Rust Based Game Engine

Goal

Game Engine will house components and systems that every game needs. Game Engine contains WebGL rendering with GLM functionality.

Features (WIP)

• WebGL Renderer and GLSL Shaders
• GLM Functions and Data Structures
• Mesh management
• ECS management
• Javascript app, log, and input hooks

sawd_glm

This project requires you also download my other project: sawd_glm

Update the Cargo.toml file with the path that best suits you.

How to Include

Pull this repo and reference it locally through your cargo.toml

[dependencies.gameengine]
path = "../wip-rust-game-engine"

Then in your lib.rs you can reference it by the name given above

extern crate gameengine;

Below that create your application with the built in macro

//make application BB
create_app!(Template);

// MAIN
#[wasm_bindgen]
pub fn run(canvas_id : String) -> Result<Application, JsValue> {
    // hook panics to the console
    panic::set_hook(Box::new(console_error_panic_hook::hook));

    let mut engine = Engine::new(canvas_id)?;
    let game = Template::new(&mut engine);

    let app = Application::new(engine, game);

    Ok(app)
}

Now you can hook your application in javascript

(async () => {
    // import game as webGL
    const webGL = await import('./wasm/game.js');

    // pass the id of the html canvas we're rendering to
    // receive game instance from webGL.run()
    const Game = webGL.run('canvas');

    // function that will call Game.tick() and then request another frame
    const renderLoop = () => {
        Game.tick();
        requestAnimationFrame(renderLoop);
    }

    // hook up your input functions
    document.addEventListener('mousedown', mouseDown, false);
    document.addEventListener('mouseup', mouseUp, false);
    document.addEventListener('mousemove', mouseMove, false);
    document.addEventListener('wheel', updateScroll, false);
    document.addEventListener('keydown', keyDown, false);
    document.addEventListener('keyup', keyUp, false);

    function mouseMove(e) { Game.js_mouse_move(e.screenX, e.screenY, e.movementX, e.movementY); }
    function mouseDown(e) { Game.js_mouse_press(e.button, e.buttons, e.screenX, e.screenY); }
    function mouseUp(e) { Game.js_mouse_release(e.button, e.buttons, e.screenX, e.screenY); }
    function updateScroll(e) { Game.js_mouse_scroll(e.deltaY); }
    function keyDown(e) { Game.js_key_down(e.keyCode); }
    function keyUp(e) { Game.js_key_up(e.keyCode); }

    // kick off endless loop
    requestAnimationFrame(renderLoop);
})();