// Neuro-Evolution Flappy Bird with ml5.js

​

const TOTAL = 100;

// Current birds

const birds = [];

// Save any birds that die

let savedBirds = [];

let pipes = [];

let counter = 0;

let slider;

​

function setup() {

  createCanvas(640, 480);

  // Improves performance for small neural networks and classifySync()

  ml5.tf.setBackend("cpu");

​

  // Slider for speeding up simulation

  slider = createSlider(1, 10, 1);

​

  // Create initial population of birds

  for (let i = 0; i < TOTAL; i += 1) {

    birds[i] = new Bird();

  }

}

​

function draw() {

  // Speed up simulation

  for (let n = 0; n < slider.value(); n += 1) {

    // new pipes every N frames

    if (counter % 75 === 0) {

      pipes.push(new Pipe());

    }

    counter += 1;

​

    // Run game

    for (let i = pipes.length - 1; i >= 0; i -= 1) {

      pipes[i].update();

​

      for (let j = birds.length - 1; j >= 0; j -= 1) {

        if (pipes[i].hits(birds[j])) {

          // Save bird if it dies

          savedBirds.push(birds.splice(j, 1)[0]);

        }

      }

​

      // Remove pipes when they leave

      if (pipes[i].offscreen()) {

        pipes.splice(i, 1);

      }

    }

​

    // Remove / save any birds that go offscreen

    for (let i = birds.length - 1; i >= 0; i -= 1) {

      if (birds[i].offScreen()) {

        savedBirds.push(birds.splice(i, 1)[0]);

      }

    }

​

    // Run all birds

    for (const bird of birds) {

      bird.think(pipes);

      bird.update();

    }

​

    // If all the birds have died go to the next generation

    if (birds.length === 0) {

      counter = 0;

      nextGeneration();

      pipes = [];

    }

  }

​

  // All the drawing stuff

  background(0);

​

  for (const bird of birds) {

    bird.show();

  }

​

  for (const pipe of pipes) {

    pipe.show();

  }

}

​