const cities = [];

const totalCities = 15;

​

const popSize = 500;

const fitness = [];

​

let population = [];

let recordDistance = Infinity;

let bestEver;

let currentBest;

​

let statusP;

​

function setup() {

  createCanvas(600, 600);

  const order = [];

  for (let i = 0; i < totalCities; i++) {

    const v = createVector(random(width), random(height / 2));

    cities[i] = v;

    order[i] = i;

  }

​

  for (let i = 0; i < popSize; i++) {

    population[i] = shuffle(order);

  }

  statusP = createP('').style('font-size', '32pt');

}

​

function draw() {

  background(0);

​

  // GA

  calculateFitness();

  normalizeFitness();

  nextGeneration();

​

  stroke(255);

  strokeWeight(4);

  noFill();

  beginShape();

  for (let i = 0; i < bestEver.length; i++) {

    const n = bestEver[i];

    vertex(cities[n].x, cities[n].y);

    ellipse(cities[n].x, cities[n].y, 16, 16);

  }

  endShape();

​

  translate(0, height / 2);

  stroke(255);

  strokeWeight(4);

  noFill();

  beginShape();

  for (let i = 0; i < currentBest.length; i++) {

    const n = currentBest[i];

    vertex(cities[n].x, cities[n].y);

    ellipse(cities[n].x, cities[n].y, 16, 16);

  }

  endShape();

​

}

​

// function shuffle(a, num) {

//   for (var i = 0; i < num; i++) {

//     var indexA = floor(random(a.length));

//     var indexB = floor(random(a.length));

//     swap(a, indexA, indexB);

//   }

// }

​

​

function swap(a, i, j) {

  const temp = a[i];

  a[i] = a[j];

  a[j] = temp;

}

​

​

function calcDistance(points, order) {

  let sum = 0;

  for (let i = 0; i < order.length - 1; i++) {

    const cityAIndex = order[i];

    const cityA = points[cityAIndex];

    const cityBIndex = order[i + 1];

    const cityB = points[cityBIndex];

    const d = dist(cityA.x, cityA.y, cityB.x, cityB.y);

    sum += d;

  }

  return sum;

}