var renderer;
var spriteBatch;

// game loop timing
var nowTick = timestamp();
var dt = 0;
var lastTick;
var step = 1 / 60;

var texTest;

function main() {
    var canvas = document.getElementById("game-canvas");

    renderer = new Renderer(canvas);
    renderer.initialise();

    spriteBatch = new SpriteBatch(renderer);

    texTest = new Texture(renderer, "client/assets/graphics/misc/cursor.png");

    // start game.
    frame();
}

function frame() {
    nowTick = timestamp();
    dt = Math.min(1, (nowTick - lastTick) / 1000); // deltaTime in seconds
    while (dt > step) {
        dt = dt - step;
        update(step);
    }
    draw(dt);
    lastTick = nowTick;
    requestAnimationFrame(frame);
}

function update(dt) {

}

function draw(dt) {
    spriteBatch.begin();

    for (var i = 0; i < 500; i++) {
        spriteBatch.draw(texTest,
            { x: i, y: 50, width: 26, height: 32 },
            { x: 0, y: 0, width: 26, height: 32 });
    }

    spriteBatch.end();
}

function timestamp() {
    return window.performance && window.performance.now ? window.performance.now() : new Date().getTime();
}

main();